Reversing resistance to vascular-disrupting agents by blocking late mobilization of circulating endothelial progenitor cells.

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Taylor, Melissa; Billiot, Fanny; Marty, Virginie; Rouffiac, Valérie; Cohen, Patrick; Tournay, Elodie; Opolon, Paule; Louache, Fawzia; Vassal, Gilles; Laplace-Builhé, Corinne; Vielh, Philippe; Soria, Jean-Charles; Farace, Françoise

2012-05-01

The prevailing concept is that immediate mobilization of bone marrow-derived circulating endothelial progenitor cells (CEP) is a key mechanism mediating tumor resistance to vascular-disrupting agents (VDA). Here, we show that administration of VDA to tumor-bearing mice induces 2 distinct peaks in CEPs: an early, unspecific CEP efflux followed by a late yet more dramatic tumor-specific CEP burst that infiltrates tumors and is recruited to vessels. Combination with antiangiogenic drugs could not disrupt the early peak but completely abrogated the late VDA-induced CEP burst, blunted bone marrow-derived cell recruitment to tumors, and resulted in striking antitumor efficacy, indicating that the late CEP burst might be crucial to tumor recovery after VDA therapy. CEP and circulating endothelial cell kinetics in VDA-treated patients with cancer were remarkably consistent with our preclinical data. These findings expand the current understanding of vasculogenic "rebounds" that may be targeted to improve VDA-based strategies. Our findings suggest that resistance to VDA therapy may be strongly mediated by late, rather than early, tumor-specific recruitment of CEPs, the suppression of which resulted in increased VDA-mediated antitumor efficacy. VDA-based therapy might thus be significantly enhanced by combination strategies targeting late CEP mobilization. © 2012 AACR

Kinetics of circulating endothelial progenitor cells in patients undergoing carotid artery surgery

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Kalender G

2016-12-01

Full Text Available G Kalender,1 A Kornberger,2 M Lisy,1 Andres Beiras-Fernandez,2 UA Stock2 1Deparment of General, Thoracic and Vascular Surgery, Hoechst Hospital, 2Department of Thoracic and Cardiovascular Surgery, University Hospital Frankfurt, Frankfurt am Main, Germany Aim: Endothelial progenitor cells (EPCs are primitive cells found in the bone marrow and peripheral blood (PB. In particular, the potential of EPCs to differentiate into mature endothelial cells remains of high interest for clinical applications such as bio-functionalized patches for autologous seeding after implantation. The objective of this study was to determine EPCs’ kinetics in patients undergoing carotid artery thromboendarterectomy (CTEA and patch angioplasty. Methods: Twenty CTEA patients were included (15 male, mean age 76 years. PB samples were taken at 1 day preoperatively, and at 1, 3, and 5 days postoperatively. Flow cytometric analysis was performed for CD34, CD133, KDR, and CD45. Expression of KDR, SDF-1α, and G-CSF was analyzed by means of enzyme-linked immunosorbent assay. Results: Fluorescence-activated cell sorting analysis revealed 0.031%±0.016% (% of PB mononuclear cells KDR+ cells and 0.052%±0.022% CD45-/CD34+/CD133+ cells, preoperatively. A 33% decrease of CD45–/CD34+/CD133+ cells was observed at day 1 after surgery. However, a relative number (compared to initial preoperative values of CD45-/CD34+/CD133+ cells was found on day 3 (82% and on day 5 (94% postoperatively. More profound upregulated levels of CD45–CD34+/CD133+ cells were observed for diabetic (+47% compared to nondiabetic and male (+38% compared to female patients. No significant postoperative time-dependent differences were found in numbers of KDR+ cells and the concentrations of the cytokines KDR and G-CSF. However, the SDF-1α levels decreased significantly on day 1 postoperatively but returned to preoperative levels by day 3. Conclusion: CTEA results in short-term downregulation of circulating

Analysis of circulating hem-endothelial marker RNA levels in preterm infants

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Kuint Jacob

2009-06-01

Full Text Available Abstract Background Circulating endothelial cells may serve as novel markers of angiogenesis. These include a subset of hem-endothelial progenitor cells that play a vital role in vascular growth and repair. The presence and clinical implications of circulating RNA levels as an expression for hematopoietic and endothelial-specific markers have not been previously evaluated in preterm infants. This study aims to determine circulating RNA levels of hem-endothelial marker genes in peripheral blood of preterm infants and begin to correlate these findings with prenatal complications. Methods Peripheral blood samples from seventeen preterm neonates were analyzed at three consecutive post-delivery time points (day 3–5, 10–15 and 30. Using quantitative reverse transcription-polymerase chain reaction we studied the expression patterns of previously established hem-endothelial-specific progenitor-associated genes (AC133, Tie-2, Flk-1 (VEGFR2 and Scl/Tal1 in association with characteristics of prematurity and preterm morbidity. Results Circulating Tie-2 and SCL/Tal1 RNA levels displayed an inverse correlation to gestational age (GA. We observed significantly elevated Tie-2 levels in preterm infants born to mothers with amnionitis, and in infants with sustained brain echogenicity on brain sonography. Other markers showed similar expression patterns yet we could not demonstrate statistically significant correlations. Conclusion These preliminary findings suggest that circulating RNA levels especially Tie2 and SCL decline with maturation and might relate to some preterm complication. Further prospective follow up of larger cohorts are required to establish this association.

Circulating endothelial progenitor cell numbers are not associated with donor organ age or allograft vasculopathy in cardiac transplant recipients.

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Thomas, H E; Parry, G; Dark, J H; Arthur, H M; Keavney, B D

2009-02-01

Increasing age is associated with reduced numbers of circulating endothelial progenitor cells (EPCs). It is unclear whether this relates to depletion or impairment of bone marrow progenitors, or to deficient mobilization signals from aging tissues. In cardiac transplant patients, one previous study has reported an association between circulating EPCs and the risk of cardiac allograft vasculopathy (CAV). We investigated whether increased donor heart age, a strong risk factor for CAV, was associated with reduced circulating EPC numbers in a group of cardiac transplant recipients matched for factors which influence EPC numbers, but with maximally discordant donor heart ages. We identified 32 patient pairs, matched for factors known to influence EPC numbers, but who had discordant donor heart ages by at least 20 years. EPCs were quantified using flow cytometry for absolute counts of cells expressing all the combinations of CD45, CD34, CD133 and the kinase domain receptor (KDR). There were no significant differences in the numbers of circulating EPCs between patients with old or young donor heart age. There was no association between the presence of CAV and circulating EPC numbers. We suggest that the increased susceptibility to CAV of older donor hearts is not mediated via circulating EPCs. Our results are consistent with the theory that the normal age-related decline in EPC numbers relates to bone marrow aging rather than failure of target tissues to induce EPC mobilization.

The Effects of Inhaled Nickel Nanoparticles on Murine Endothelial Progenitor Cells

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Liberda, Eric N.

Introduction. Particulate air pollution, specifically nickel found on or in particulate matter, has been associated with an increased risk of mortality in human population studies and can cause increases in vascular inflammation, generate reactive oxygen species, alter vasomotor tone, and potentiate atherosclerosis in murine exposures. With the discovery of endothelial progenitor cells (EPCs), a door has been opened which may explain these observed cardiovascular effects associated with inhaled air particles and nickel exposure. In order to further quantify the effects of inhaled nickel nanoparticles and attempt to elucidate how the observed findings from other studies may occur, several whole body inhalation exposure experiments to nickel nanoparticles were performed. Methods. Following whole body exposure to approximately 500mug/m3 of nickel nanoparticles for 5 hrs, bone marrow EPCs from C57BL/6 mice were isolated. EPCs were harvested for their RNA or used in a variety of assays including chemotaxis, tube formation, and proliferation. Gene expression was assessed for important receptors involved in EPC mobilization and homing using RT-PCR methods. EPCs, circulating endothelial progenitor cells, circulating endothelial cells (CECs), and endothelial microparticles (EMPs) were quantified on a BD FACSCalibur to examine endothelial damage and repair associated with the inhalation exposure. Plasma proteins were assessed using the 2D DIGE proteomic approach and commercially available ELISAs. Results and Conclusions. Exposure to inhaled nickel nanoparticles significantly increased both bone marrow EPCs as well as their levels in circulation. CECs were significantly upregulated suggesting that endothelial damage occurred due to the exposure. There was no significant difference in EMPs between the two groups. Tube formation and chemotaxis, but not proliferation, of bone marrow EPCs was impaired in the nickel nanoparticle exposed group. This decrease in EPC function

The acute exposure effects of inhaled nickel nanoparticles on murine endothelial progenitor cells.

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Liberda, Eric N; Cuevas, Azita K; Qu, Qingshan; Chen, Lung Chi

2014-08-01

The discovery of endothelial progenitor cells (EPCs) may help to explain observed cardiovascular effects associated with inhaled nickel nanoparticle exposures, such as increases in vascular inflammation, generation of reactive oxygen species, altered vasomotor tone and potentiated atherosclerosis in murine species. Following an acute whole body inhalation exposure to 500 µg/m(3) of nickel nanoparticles for 5 h, bone marrow EPCs from C57BL/6 mice were isolated. EPCs were harvested for their RNA or used in a variety of assays including chemotaxis, tube formation and proliferation. Gene expression was assessed for important receptors involved in EPC mobilization and homing using RT-PCR methods. EPCs, circulating endothelial progenitor cells (CEPCs), circulating endothelial cells (CECs) and endothelial microparticles (EMPs) were quantified on a BD FACSCalibur to examine endothelial damage and repair associated with the exposure. Acute exposure to inhaled nickel nanoparticles significantly increased both bone marrow EPCs as well as their levels in circulation (CEPCs). CECs were significantly elevated indicating that endothelial damage occurred due to the exposure. There was no significant difference in EMPs between the two groups. Tube formation and chemotaxis, but not proliferation, of bone marrow EPCs was impaired in the nickel nanoparticle exposed group. These results coincided with a decrease in the mRNA of receptors involved in EPC mobilization and homing. These data provide new insight into how an acute nickel nanoparticle exposure to half of the current Occupational Safety & Health Administration (OSHA) permissible exposure limit may adversely affect EPCs and exacerbate cardiovascular disease states.

Strategies to reverse endothelial progenitor cell dysfunction in diabetes.

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Petrelli, Alessandra; Di Fenza, Raffaele; Carvello, Michele; Gatti, Francesca; Secchi, Antonio; Fiorina, Paolo

2012-01-01

Bone-marrow-derived cells-mediated postnatal vasculogenesis has been reported as the main responsible for the regulation of vascular homeostasis in adults. Since their discovery, endothelial progenitor cells have been depicted as mediators of postnatal vasculogenesis for their peculiar phenotype (partially staminal and partially endothelial), their ability to differentiate in endothelial cell line and to be incorporated into the vessels wall during ischemia/damage. Diabetes mellitus, a condition characterized by cardiovascular disease, nephropathy, and micro- and macroangiopathy, showed a dysfunction of endothelial progenitor cells. Herein, we review the mechanisms involved in diabetes-related dysfunction of endothelial progenitor cells, highlighting how hyperglycemia affects the different steps of endothelial progenitor cells lifetime (i.e., bone marrow mobilization, trafficking into the bloodstream, differentiation in endothelial cells, and homing in damaged tissues/organs). Finally, we review preclinical and clinical strategies that aim to revert diabetes-induced dysfunction of endothelial progenitor cells as a means of finding new strategies to prevent diabetic complications.

Strategies to Reverse Endothelial Progenitor Cell Dysfunction in Diabetes

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Alessandra Petrelli

2012-01-01

Full Text Available Bone-marrow-derived cells-mediated postnatal vasculogenesis has been reported as the main responsible for the regulation of vascular homeostasis in adults. Since their discovery, endothelial progenitor cells have been depicted as mediators of postnatal vasculogenesis for their peculiar phenotype (partially staminal and partially endothelial, their ability to differentiate in endothelial cell line and to be incorporated into the vessels wall during ischemia/damage. Diabetes mellitus, a condition characterized by cardiovascular disease, nephropathy, and micro- and macroangiopathy, showed a dysfunction of endothelial progenitor cells. Herein, we review the mechanisms involved in diabetes-related dysfunction of endothelial progenitor cells, highlighting how hyperglycemia affects the different steps of endothelial progenitor cells lifetime (i.e., bone marrow mobilization, trafficking into the bloodstream, differentiation in endothelial cells, and homing in damaged tissues/organs. Finally, we review preclinical and clinical strategies that aim to revert diabetes-induced dysfunction of endothelial progenitor cells as a means of finding new strategies to prevent diabetic complications.

Circulating endothelial progenitor cells, Th1/Th2/Th17-related cytokines, and endothelial dysfunction in resistant hypertension.

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Magen, Eli; Feldman, Arie; Cohen, Ziona; Alon, Dora Ben; Minz, Evegeny; Chernyavsky, Alexey; Linov, Lina; Mishal, Joseph; Schlezinger, Menacham; Sthoeger, Zev

2010-02-01

A possible link between chronic vascular inflammation and arterial hypertension is now an object of intensive studies. To compare Th1/Th2/Th17 cells-related cytokines, circulating endothelial progenitor cells (EPC), and endothelial function in subjects with resistant arterial hypertension (RAH) and controlled arterial hypertension (CAH). Blood pressure was measured by electronic sphygmomanometer. EPC were identified as CD34+/CD133+/kinase insert domain receptor (KDR)+ cells by flow cytometry. Th1/Th2/Th17 cells-related cytokines were identified using the Human Th1/Th2/Th17 Cytokines MultiAnalyte ELISArray Kit. Endothelium-dependent (FMD) vasodilatation of brachial artery was measured by Doppler ultrasound scanning. RAH group (n = 20) and CAH group (n = 20) and 17 healthy individuals (control group) were recruited. In the RAH group, lower blood levels of EPC number (42.4 +/- 16.7 cells/mL) and EPC% (0.19 +/- 0.08%) were observed than in the CAH group (93.1 +/- 88.7 cells/mL; P = 0.017; 0.27 +/- 0.17; P = 0.036) and control group (68.5 +/- 63.6 cells/mL; P < 0.001; 0.28 +/- 0.17%; P = 0.003), respectively. Plasma transforming growth factor-beta1 levels were significantly higher in the RAH group (1767 +/- 364 pg/mL) than in the CAH group (1292 +/- 349; P < 0.001) and in control group (1203 +/- 419 pg/mL; P < 0.001). In the RAH group, statistically significant negative correlation was observed between systolic blood pressure and EPC% (r = -0.72, P < 0.01). FMD in the RAH group was significantly lower (5.5 +/- 0.8%) than in the CAH group (9.2 +/- 1.4; P < 0.001) and in healthy controls (10.1 +/- 1.1%; P < 0.001). RAH is characterized by reduced circulating EPC, substantial endothelial dysfunction, and increased plasma transforming growth factor-beta1 levels.

Endothelial Progenitor Cells for Diagnosis and Prognosis in Cardiovascular Disease

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Caterina Oriana Aragona

2016-01-01

Full Text Available Objective. To identify, evaluate, and synthesize evidence on the predictive power of circulating endothelial progenitor cells (EPCs in cardiovascular disease, through a systematic review of quantitative studies. Data Sources. MEDLINE was searched using keywords related to “endothelial progenitor cells” and “endothelium” and, for the different categories, respectively, “smoking”; “blood pressure”; “diabetes mellitus” or “insulin resistance”; “dyslipidemia”; “aging” or “elderly”; “angina pectoris” or “myocardial infarction”; “stroke” or “cerebrovascular disease”; “homocysteine”; “C-reactive protein”; “vitamin D”. Study Selection. Database hits were evaluated against explicit inclusion criteria. From 927 database hits, 43 quantitative studies were included. Data Syntheses. EPC count has been suggested for cardiovascular risk estimation in the clinical practice, since it is currently accepted that EPCs can work as proangiogenic support cells, maintaining their importance as regenerative/reparative potential, and also as prognostic markers. Conclusions. EPCs showed an important role in identifying cardiovascular risk conditions, and to suggest their evaluation as predictor of outcomes appears to be reasonable in different defined clinical settings. Due to their capability of proliferation, circulation, and the development of functional progeny, great interest has been directed to therapeutic use of progenitor cells in atherosclerotic diseases. This trial is registered with registration number: Prospero CRD42015023717.

Smoking decreases the level of circulating CD34+ progenitor cells in young healthy women - a pilot study

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Baumann Gert

2010-05-01

Full Text Available Abstract Background Decreased levels of circulating bone marrow-derived progenitor cells have been associated with risk factors and cardiovascular diseases. Smoking is the most important modifiable risk factor for atherosclerosis in young women. The aim of this pilot study was to assess in healthy premenopausal women without other risk factors for cardiovascular disease the influence of nicotine abuse on the number of circulating progenitor cells in relation to endothelial function. Methods The number of endothelial progenitor cells, measured as colony-forming units in a cell-culture assay (EPC-CFU and the number of circulating CD34 + and CD34 + /CD133 + cells, measured by flow cytometry, was estimated in 32 women at the menstrual phase of the menstrual cycle. In addition, flow-mediated dilation (FMD was assessed as a marker for vascular function. In a subgroup of these women (n = 20, progenitor cells were also investigated at the mid-follicular and luteal phases of the menstrual cycle. Results Compared to non-smokers, the abundance of circulating CD34 + cells was significantly lower in smoking women in the menstrual, mid-luteal, and mid-follicular phases of the menstrual cycle. The number of CD34 + progenitor cells was revealed to have significant positive correlation with FMD in young healthy women, whereas CD34 + /CD133 + progenitor cells and EPC-CFU showed no significant correlation. Conclusion The number of CD34 + progenitor cells positively correlates with FMD in young healthy women and is decreased by smoking.

High levels of circulating VEGFR2+ Bone marrow-derived progenitor cells correlate with metastatic disease in patients with pediatric solid malignancies.

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Taylor, Melissa; Rössler, Jochen; Geoerger, Birgit; Laplanche, Agnès; Hartmann, Olivier; Vassal, Gilles; Farace, Françoise

2009-07-15

Pediatric solid malignancies display important angiogenic potential, and blocking tumor angiogenesis represents a new therapeutic approach for these patients. Recent studies have evidenced rare circulating cells with endothelial features contributing to tumor neovascularization and have shown the pivotal role of bone marrow-derived (BMD) progenitor cells in metastatic disease progression. We measured these cells in patients with pediatric solid malignancies as a prerequisite to clinical trials with antiangiogenic therapy. Peripheral blood was drawn from 45 patients with localized (n = 23) or metastatic (n = 22) disease, and 20 healthy subjects. Subsets of circulating vascular endothelial growth factor receptor (VEGFR)2+-BMD progenitor cells, defined as CD45-CD34+VEGFR2(KDR)+7AAD- and CD45(dim)CD34+VEGFR2+7AAD- events, were measured in progenitor-enriched fractions by flow cytometry. Mature circulating endothelial cells (CEC) were measured in whole blood as CD31+CD146+CD45-7AAD- viable events. Data were correlated with VEGF and sVEGFR2 plasma levels. The CD45-CD34+VEGFR2(KDR)+7AAD- subset represented <0.003% of circulating BMD progenitor cells (< or =0.05 cells/mL). However, the median level (range) of the CD45(dim)CD34+VEGFR2+7AAD- subset was higher in patients compared with healthy subjects, 1.5% (0%-10.3%) versus 0.3% (0%-1.6%) of circulating BMD progenitors (P < 0.0001), and differed significantly between patients with localized and metastatic disease, 0.7% (0%-8.6%) versus 2.9% (0.6%-10.3%) of circulating BMD progenitors (P < 0.001). Median CEC value was 7 cells/mL (0-152 cells/mL) and similar in all groups. Unlike VEGFR2+-BMD progenitors, neither CECs, VEGF, or sVEGFR2 plasma levels correlated with disease status. High levels of circulating VEGFR2+-BMD progenitor cells correlated with metastatic disease. Our study provides novel insights for angiogenesis mechanisms in pediatric solid malignancies for which antiangiogenic targeting of VEGFR2+-BMD progenitors

Mouse lung contains endothelial progenitors with high capacity to form blood and lymphatic vessels

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Barleon Bernhard

2010-07-01

Full Text Available Abstract Background Postnatal endothelial progenitor cells (EPCs have been successfully isolated from whole bone marrow, blood and the walls of conduit vessels. They can, therefore, be classified into circulating and resident progenitor cells. The differentiation capacity of resident lung endothelial progenitor cells from mouse has not been evaluated. Results In an attempt to isolate differentiated mature endothelial cells from mouse lung we found that the lung contains EPCs with a high vasculogenic capacity and capability of de novo vasculogenesis for blood and lymph vessels. Mouse lung microvascular endothelial cells (MLMVECs were isolated by selection of CD31+ cells. Whereas the majority of the CD31+ cells did not divide, some scattered cells started to proliferate giving rise to large colonies (> 3000 cells/colony. These highly dividing cells possess the capacity to integrate into various types of vessels including blood and lymph vessels unveiling the existence of local microvascular endothelial progenitor cells (LMEPCs in adult mouse lung. EPCs could be amplified > passage 30 and still expressed panendothelial markers as well as the progenitor cell antigens, but not antigens for immune cells and hematopoietic stem cells. A high percentage of these cells are also positive for Lyve1, Prox1, podoplanin and VEGFR-3 indicating that a considerabe fraction of the cells are committed to develop lymphatic endothelium. Clonogenic highly proliferating cells from limiting dilution assays were also bipotent. Combined in vitro and in vivo spheroid and matrigel assays revealed that these EPCs exhibit vasculogenic capacity by forming functional blood and lymph vessels. Conclusion The lung contains large numbers of EPCs that display commitment for both types of vessels, suggesting that lung blood and lymphatic endothelial cells are derived from a single progenitor cell.

Increased circulating endothelial apoptotic microparticle to endothelial progenitor cell ratio is associated with subsequent decline in glomerular filtration rate in hypertensive patients.

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Chien-Yi Hsu

Full Text Available BACKGROUND: Recent research indicates hypertensive patients with microalbuminuria have decreased endothelial progenitor cells (EPCs and increased levels of endothelial apoptotic microparticles (EMP. However, whether these changes are related to a subsequent decline in glomerular filtration rate (GFR remains unclear. METHODS AND RESULTS: We enrolled totally 100 hypertensive out-patients with eGFR ≥ 30 mL/min/1.73 m(2. The mean annual rate of GFR decline (△GFR/y was -1.49 ± 3.26 mL/min/1.73 m(2 per year during the follow-up period (34 ± 6 months. Flow cytometry was used to assess circulating EPC (CD34(+/KDR(+ and EMP levels (CD31(+/annexin V(+ in peripheral blood. The △GFR/y was correlated with the EMP to EPC ratio (r= -0.465, p<0.001, microalbuminuria (r= -0.329, p=0.001, and the Framingham risk score (r= -0.245, p=0.013. When we divided the patients into 4 groups according to the EMP to EPC ratio, there was an association between the EMP to EPC ratio and the ΔGFR/y (mean ΔGFR/y: 0.08 ± 3.04 vs. -0.50 ± 2.84 vs. -1.25 ± 2.49 vs. -4.42 ± 2.82, p<0.001. Multivariate analysis indicated that increased EMP to EPC ratio is an independent predictor of ΔeGFR/y. CONCLUSIONS: An increased circulating EMP to EPC ratio is associated with subsequent decline in GFR in hypertensive patients, which suggests endothelial damage with reduced vascular repair capacity may contribute to further deterioration of renal function in patients with hypertension.

Cathepsin L is required for endothelial progenitor cell-induced neovascularization

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Urbich, Carmen; Heeschen, Christopher; Aicher, Alexandra; Sasaki, Ken-ichiro; Bruhl, Thomas; Hofmann, Wolf K.; Peters, Christoph; Reinheckel, Thomas; Pennacchio, Len A.; Abolmaali, Nasreddin D.; Chavakis, Emmanouil; Zeiher, Andreas M.; Dimmeler, Stefanie

2004-01-15

Infusion of endothelial progenitor cells (EPCs), but not of mature endothelial cells (ECs), promotes neovascularization after ischemia. We performed a gene expression profiling of EPCs and ECs to identify genes, which might be important for the neovascularization capacity of EPCs. Intriguingly, the protease cathepsin L (CathL) was highly expressed in EPCs as opposed to ECs and is essential for matrix degradation and invasion by EPCs in vitro. CathL deficient mice showed impaired functional recovery after hind limb ischemia supporting the concept for an important role of CathL in postnatal neovascularization. Infused CathL deficient progenitor cells failed to home to sites of ischemia and to augment neovascularization. In contrast, over expression of CathL in mature ECs significantly enhanced their invasive activity and induced their neovascularization capacity in vivo. Taken together, CathL plays a crucial role for the integration of circulating EPCs into the ischemic tissue and is required for neovascularization mediated by EPCs.

Vildagliptin, but not glibenclamide, increases circulating endothelial progenitor cell number: a 12-month randomized controlled trial in patients with type 2 diabetes.

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Dei Cas, Alessandra; Spigoni, Valentina; Cito, Monia; Aldigeri, Raffaella; Ridolfi, Valentina; Marchesi, Elisabetta; Marina, Michela; Derlindati, Eleonora; Aloe, Rosalia; Bonadonna, Riccardo C; Zavaroni, Ivana

2017-02-23

Fewer circulating endothelial progenitor cells (EPCs) and increased plasma (C-term) stromal cell-derived factor 1α (SDF-1α), a substrate of DPP-4, are biomarkers, and perhaps mediators, of cardiovascular risk and mortality. Short-term/acute treatment with DPP-4 inhibitors improve EPC bioavailability; however, long-term effects of DPP-4i on EPCs bioavailability/plasma (C-term) SDF-1α are unknown. Randomized (2:1) open-label trial to compare the effects of vildagliptin (V) (100 mg/day) vs glibenclamide (G) (2.5 mg bid to a maximal dose of 5 mg bid) on circulating EPC levels at 4 and 12 months of treatment in 64 patients with type 2 diabetes in metformin failure. At baseline, and after 4 and 12 months, main clinical/biohumoral parameters, inflammatory biomarkers, concomitant therapies, EPC number (CD34 + /CD133 + /KDR + /10 6 cytometric events) and plasma (C-term) SDF-1α (R&D system) were assessed. Baseline characteristics were comparable in the two groups. V and G similarly and significantly (p < 0.0001) improved glucose control. At 12 months, V significantly increased EPC number (p < 0.05) and significantly reduced (C-term) SDF-1α plasma levels (p < 0.01) compared to G, with no differences in inflammatory biomarkers. V exerts a long-term favorable effect on EPC and (C-term) SDF-1α levels at glucose equipoise, thereby implying a putative beneficial effect on vascular integrity. Trial registration Clinical Trials number: NCT01822548; name: Effect of Vildagliptin vs. Glibenclamide on Circulating Endothelial Progenitor Cell Number Type 2 Diabetes. Registered 28 March, 2013.

Exposure to ultrafine particles, intracellular production of reactive oxygen species in leukocytes and altered levels of endothelial progenitor cells

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Jantzen, Kim; Møller, Peter Horn; Karottki, Dorina Gabriela

2016-01-01

. Additionally, the early endothelial progenitor cell levels were positively associated with a personalised measure of ultrafine particle exposure and negatively associated with both basal and capacity for reactive oxygen species production in lymphocytes and granulocytes, respectively. Our results indicate......Exposure to particles in the fine and ultrafine size range has been linked to induction of low-grade systemic inflammation, oxidative stress and development of cardiovascular diseases. Declining levels of endothelial progenitor cells within systemic circulation have likewise been linked...... to progression of cardiovascular diseases. The objective was to determine if exposure to fine and ultrafine particles from indoor and outdoor sources, assessed by personal and residential indoor monitoring, is associated with altered levels of endothelial progenitor cells, and whether such effects are related...

Improving the characterization of endothelial progenitor cell subsets by an optimized FACS protocol.

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Karin Huizer

Full Text Available The characterization of circulating endothelial progenitor cells (EPCs is fundamental to any study related to angiogenesis. Unfortunately, current literature lacks consistency in the definition of EPC subsets due to variations in isolation strategies and inconsistencies in the use of lineage markers. Here we address critical points in the identification of hematopoietic progenitor cells (HPCs, circulating endothelial cells (CECs, and culture-generated outgrowth endothelial cells (OECs from blood samples of healthy adults (AB and umbilical cord (UCB. Peripheral blood mononuclear cells (PBMCs were enriched using a Ficoll-based gradient followed by an optimized staining and gating strategy to enrich for the target cells. Sorted EPC populations were subjected to RT-PCR for tracing the expression of markers beyond the limits of cell surface-based immunophenotyping. Using CD34, CD133 and c-kit staining, combined with FSC and SSC, we succeeded in the accurate and reproducible identification of four HPC subgroups and found significant differences in the respective populations in AB vs. UCB. Co-expression analysis of endothelial markers on HPCs revealed a complex pattern characterized by various subpopulations. CECs were identified by using CD34, KDR, CD45, and additional endothelial markers, and were subdivided according to their apoptotic state and expression of c-kit. Comparison of UCB-CECs vs. AB-CECs revealed significant differences in CD34 and KDR levels. OECs were grown from PBMC-fractions We found that viable c-kit+ CECs are a candidate circulating precursor for CECs. RT-PCR to angiogenic factors and receptors revealed that all EPC subsets expressed angiogenesis-related molecules. Taken together, the improvements in immunophenotyping and gating strategies resulted in accurate identification and comparison of better defined cell populations in a single procedure.

Exposure to ultrafine particles, intracellular production of reactive oxygen species in leukocytes and altered levels of endothelial progenitor cells

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Jantzen, Kim; Møller, Peter; Karottki, Dorina Gabriela; Olsen, Yulia; Bekö, Gabriel; Clausen, Geo; Hersoug, Lars-Georg; Loft, Steffen

2016-01-01

Exposure to particles in the fine and ultrafine size range has been linked to induction of low-grade systemic inflammation, oxidative stress and development of cardiovascular diseases. Declining levels of endothelial progenitor cells within systemic circulation have likewise been linked to progression of cardiovascular diseases. The objective was to determine if exposure to fine and ultrafine particles from indoor and outdoor sources, assessed by personal and residential indoor monitoring, is associated with altered levels of endothelial progenitor cells, and whether such effects are related to leukocyte-mediated oxidative stress. The study utilized a cross sectional design performed in 58 study participants from a larger cohort. Levels of circulating endothelial progenitor cells, defined as either late (CD34 + KDR + cells) or early (CD34 + CD133 + KDR + cells) subsets were measured using polychromatic flow cytometry. We additionally measured production of reactive oxygen species in leukocyte subsets (lymphocytes, monocytes and granulocytes) by flow cytometry using intracellular 2′,7′-dichlorofluoroscein. The measurements encompassed both basal levels of reactive oxygen species production and capacity for reactive oxygen species production for each leukocyte subset. We found that the late endothelial progenitor subset was negatively associated with levels of ultrafine particles measured within the participant residences and with reactive oxygen species production capacity in lymphocytes. Additionally, the early endothelial progenitor cell levels were positively associated with a personalised measure of ultrafine particle exposure and negatively associated with both basal and capacity for reactive oxygen species production in lymphocytes and granulocytes, respectively. Our results indicate that exposure to fine and ultrafine particles derived from indoor sources may have adverse effects on human vascular health.

Tumor endothelial markers define novel subsets of cancer-specific circulating endothelial cells associated with antitumor efficacy

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Mehran, Reza; Nilsson, Monique; Khajavi, Mehrdad; Du, Zhiqiang; Cascone, Tina; Wu, Hua Kang; Cortes, Andrea; Xu, Li; Zurita, Amado; Schier, Robert; Riedel, Bernhard; El-Zein, Randa; Heymach, John V.

2014-01-01

Circulating endothelial cells (CEC) are derived from multiple sources including bone marrow (circulating endothelial progenitors [CEP]) and established vasculature (mature CEC). Although CEC have shown promise as a biomarker for cancer patients, their utility has been limited in part by the lack of specificity for tumor vasculature and the different non-malignant causes that can impact CEC. Tumor endothelial markers (TEM) are antigens enriched in tumor vs non-malignant endothelia. We hypothesized that TEMs may be detectable on CEC and that these circulating TEM+ endothelial cells (CTEC) may be a more specific marker for cancer and tumor response than standard CEC. We found that tumor-bearing mice had a relative increase in numbers of circulating CTEC, specifically with increased levels of TEM7 and TEM8 expression. Following treatment with various vascular targeting agents, we observed a decrease in CTEC that correlated with the reductions in tumor growth. We extended these findings to human clinical samples and observed that CTEC were present in esophageal cancer and non-small cell lung cancer (NSCLC) patients (N=40) and their levels decreased after surgical resection. These results demonstrate that CTEC are detectable in preclinical cancer models and cancer patients. Further, they suggest that CTEC offer a novel cancer-associated marker that may be useful as a blood-based surrogate for assessing the presence of tumor vasculature and antiangiogenic drug activity. PMID:24626092

Impact of age and gender interaction on circulating endothelial progenitor cells in healthy subjects.

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Rousseau, Alexandra; Ayoubi, Fida; Deveaux, Christel; Charbit, Beny; Delmau, Catherine; Christin-Maitre, Sophie; Jaillon, Patrice; Uzan, Georges; Simon, Tabassome

2010-02-01

To assess the level of circulating endothelial progenitor cells (CEPC) in cycling women compared with men and menopausal women. Controlled clinical study. Healthy, nonsmoking volunteers. Twelve women, aged 18-40 years, with regular menstrual cycles, 12 menopausal women, and two groups of 12 age-matched men were recruited. Women did not receive any hormone therapy. Collection of 20 mL of peripheral blood. The number of CEPC, defined as (Lin-/7AAD-/CD34+/CD133+/KDR+) cells per 10(6) mononuclear cells (MNC), was measured by flow cytometry. The number of CEPC was significantly higher in cycling women than in age-matched men and menopausal women (26.5 per 10(6) MNC vs. 10.5 per 10(6) MNC vs. 10 per 10(6) MNC, respectively). The number of CEPC was similar in menopausal women, age-matched, and young men. The number of CEPC is influenced by an age-gender interaction. This phenomenon may explain in part the better vascular repair and relative cardiovascular protection in younger women as compared with age-matched men. Copyright 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Circulating endothelial progenitor cells: a new approach to anti-aging medicine?

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Patel Amit N

2009-12-01

Full Text Available Abstract Endothelial dysfunction is associated with major causes of morbidity and mortality, as well as numerous age-related conditions. The possibility of preserving or even rejuvenating endothelial function offers a potent means of preventing/treating some of the most fearful aspects of aging such as loss of mental, cardiovascular, and sexual function. Endothelial precursor cells (EPC provide a continual source of replenishment for damaged or senescent blood vessels. In this review we discuss the biological relevance of circulating EPC in a variety of pathologies in order to build the case that these cells act as an endogenous mechanism of regeneration. Factors controlling EPC mobilization, migration, and function, as well as therapeutic interventions based on mobilization of EPC will be reviewed. We conclude by discussing several clinically-relevant approaches to EPC mobilization and provide preliminary data on a food supplement, Stem-Kine, which enhanced EPC mobilization in human subjects.

Endothelial progenitor cell subsets and preeclampsia: Findings and controversies

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Armin Attar

2017-10-01

Full Text Available Vascular remodeling is an essential component of gestation. Endothelial progenitor cells (EPCs play an important role in the regulation of vascular homeostasis. The results of studies measuring the number of EPCs in normal pregnancies and in preeclampsia have been highly controversial or even contradictory because of some variations in technical issues and different methodologies enumerating three distinct subsets of EPCs: circulating angiogenic cells (CAC, colony forming unit endothelial cells (CFU-ECs, and endothelial colony-forming cells (ECFCs. In general, most studies have shown an increase in the number of CACs in the maternal circulation with a progression in the gestational age in normal pregnancies, while functional capacities measured by CFU-ECs and ECFCs remain intact. In the case of preeclampsia, mobilization of CACs and ECFCs occurs in the peripheral blood of pregnant women, but the functional capacities shown by culture of the derived colony-forming assays (CFU-EC and ECFC assays are altered. Furthermore, the number of all EPC subsets will be reduced in umbilical cord blood in the case of preeclampsia. As EPCs play an important role in the homeostasis of vascular networks, the difference in their frequency and functionality in normal pregnancies and those with preeclampsia can be expected. In this review, there was an attempt to provide a justification for these controversies.

Quantification of circulating endothelial progenitor cells using the modified ISHAGE protocol.

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Caroline Schmidt-Lucke

2010-11-01

Full Text Available Circulating endothelial progenitor cells (EPC, involved in endothelial regeneration, neovascularisation, and determination of prognosis in cardiovascular disease can be characterised with functional assays or using immunofluorescence and flow cytometry. Combinations of markers, including CD34+KDR+ or CD133+KDR+, are used. This approach, however may not consider all characteristics of EPC. The lack of a standardised protocol with regards to reagents and gating strategies may account for the widespread inter-laboratory variations in quantification of EPC. We, therefore developed a novel protocol adapted from the standardised so-called ISHAGE protocol for enumeration of haematopoietic stem cells to enable comparison of clinical and laboratory data.In 25 control subjects, 65 patients with coronary artery disease (CAD; 40 stable CAD, 25 acute coronary syndrome/acute myocardial infarction (ACS, EPC were quantified using the following approach: Whole blood was incubated with CD45, KDR, and CD34. The ISHAGE sequential strategy was used, and finally, CD45(dimCD34(+ cells were quantified for KDR. A minimum of 100 CD34(+ events were collected. For comparison, CD45(+CD34(+ and CD45(-CD34(+ were analysed simultaneously. The number of CD45(dimCD34(+KDR(+ cells only were significantly higher in healthy controls compared to patients with CAD or ACS (p = 0.005 each, p<0.001 for trend. An inverse correlation of CD45(dimCD34(+KDR(+ with disease activity (r = -0.475, p<0.001 was confirmed. Only CD45(dimCD34(+KDR(+ correlated inversely with the number of diseased coronaries (r = -0.344; p<0.005. In a second study, a 4-week de-novo treatment of atorvastatin in stable CAD evoked an increase only of CD45(dimCD34(+KDR(+ EPC (p<0.05. CD45(+CD34(+KDR(+ and CD45(-CD34(+KDR(+ were indifferent between the three groups.Our newly established protocol adopted from the standardised ISHAGE protocol achieved higher accuracy in EPC enumeration confirming previous

Plasma levels of stromal cell-derived factor-1 (CXCL12) and circulating endothelial progenitor cells in women with idiopathic heavy menstrual bleeding.

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Elsheikh, E; Andersson, E; Sylvén, C; Ericzon, B-G; Palmblad, J; Mints, M

2014-01-01

Do plasma levels of stromal cell-derived factor-1 (CXCL12, sometimes termed SDF-1) and the numbers of circulating endothelial progenitor cells (EPCs), EPC colony-forming units (EPC-CFU) and mature endothelial cells (ECs) differ between women with idiopathic heavy menstrual bleeding of endometrial origin (HMB-E) and controls and are they related to plasma levels of other angiogenic growth factors? Angiogenesis is altered in women with HMB-E, characterized by a reduction in mean plasma levels of CXCL12, a low number of EPCs-CFUs and a high level of circulating ECs. Plasma levels of CXCL12 are significantly higher during the proliferative than the secretory phase of the menstrual cycle in healthy women and exhibit a negative correlation with blood EPC-CFUs. A prospective cohort study in a university hospital setting. Between 2008 and 2009 10 HMB-E patients were recruited from Karolinska University Hospital. Ten healthy women were also included in the analysis. Ten healthy control women and 10 HMB-E patients, all with regular menstrual cycles, provided 4 blood samples during a single menstrual cycle: 2 in the proliferative phase, 1 at ovulation and 1 in the secretory phase. We assessed plasma levels of CXCL12, vascular endothelial growth factor A(165) (VEGFA), basic fibroblast growth factor (bFGF) and granulocyte and granulocyte-macrophage colony-stimulating factors by ELISA. We counted circulating EPC-CFUs by culture, and ECs and EPCs by flow cytometry and immunostaining for cell surface markers. Plasma levels of CXCL12 were significantly lower in HMB-E patients compared with control women (P Market Insurance. The authors have no conflict of interest to declare.

Prognostic value of circulating VEGFR2+ bone marrow-derived progenitor cells in patients with advanced cancer.

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Massard, Christophe; Borget, Isabelle; Le Deley, Marie Cécile; Taylor, Melissa; Gomez-Roca, Carlos; Soria, Jean Charles; Farace, Françoise

2012-06-01

We hypothesised that host-related markers, possibly reflecting tumour aggressiveness, such as circulating endothelial cells (CEC) and circulating VEGFR2(+) bone marrow-derived (BMD) progenitor cells, could have prognostic value in patients with advanced cancer enrolled in early anticancer drug development trials. Baseline CECs (CD45(-)CD31(+)CD146(+)7AAD(-) cells) and circulating VEGFR2(+)-BMD progenitor cells (defined as CD45(dim)CD34(+)VEGFR2(+)7AAD(-) cells) were measured by flow-cytometry in 71 and 58 patients included in phase 1 trials testing novel anti-vascular or anti-angiogenic agents. Correlations between levels of CECs, circulating VEGFR2(+)-BMD progenitor cells, clinical and biological prognostic factors (i.e. the Royal Marsden Hospital (RMH) score), and overall survival (OS) were studied. The median value of CECs was 12 CEC/ml (range 0-154/ml). The median level of VEGFR2(+)-BMD progenitor cells was 1.3% (range 0-32.5%) of circulating BMD-CD34(+) progenitors. While OS was not correlated with CEC levels, it was significantly worse in patients with high VEGFR2(+)-BMD progenitor levels (>1%) (median OS 9.0 versus 17.0 months), and with a RMH prognostic score >0 (median OS 9.0 versus 24.2 months). The prognostic value of VEGFR2(+)-BMD progenitor levels remained significant (hazard ratio (HR) = 2.3, 95% confidence interval (CI), 1.1-4.6, p = 0.02) after multivariate analysis. A composite VEGFR2(+)-BMD progenitor level/RHM score ≥ 2 was significantly associated with an increased risk of death compared to scores of 0 or 1 (median OS 9.0 versus 18.4 months, HR = 2.6 (95%CI, 1.2-5.8, p = 0.02)). High circulating VEGFR2(+)-BMD progenitor levels are associated with poor prognostics and when combined to classical clinical and biological parameters could provide a new tool for patient selection in early anticancer drug trials. Copyright © 2012 Elsevier Ltd. All rights reserved.

Impact of obesity control on circulating level of endothelial progenitor cells and angiogenesis in response to ischemic stimulation

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Chen Yung-Lung

2012-07-01

Full Text Available Abstract Background and aim We tested the hypothesis that obesity reduced circulating number of endothelial progenitor cells (EPCs, angiogenic ability, and blood flow in ischemic tissue that could be reversed after obesity control. Methods 8-week-old C57BL/6J mice (n = 27 were equally divided into group 1 (fed with 22-week control diet, group 2 (22-week high fat diet, and group 3 (14-week high fat diet, followed by 8-week control diet. Critical limb ischemia (CLI was induced at week 20 in groups 2 and 3. The animals were sacrificed at the end of 22 weeks. Results Heart weight, body weight, abdominal fat weight, serum total cholesterol level, and fasting blood sugar were highest in group 2 (all p  Conclusion Obesity suppressed abilities of angiogenesis and recovery from CLI that were reversed by obesity control.

Granulocyte colony-stimulating factor mobilizes functional endothelial progenitor cells in patients with coronary artery disease.

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Powell, Tiffany M; Paul, Jonathan D; Hill, Jonathan M; Thompson, Michael; Benjamin, Moshe; Rodrigo, Maria; McCoy, J Philip; Read, Elizabeth J; Khuu, Hanh M; Leitman, Susan F; Finkel, Toren; Cannon, Richard O

2005-02-01

Endothelial progenitor cells (EPCs) that may repair vascular injury are reduced in patients with coronary artery disease (CAD). We reasoned that EPC number and function may be increased by granulocyte colony-stimulating factor (G-CSF) used to mobilize hematopoietic progenitor cells in healthy donors. Sixteen CAD patients had reduced CD34(+)/CD133(+) (0.0224+/-0.0063% versus 0.121+/-0.038% mononuclear cells [MNCs], P<0.01) and CD133(+)/VEGFR-2(+) cells, consistent with EPC phenotype (0.00033+/-0.00015% versus 0.0017+/-0.0006% MNCs, P<0.01), compared with 7 healthy controls. Patients also had fewer clusters of cells in culture, with out-growth consistent with mature endothelial phenotype (2+/-1/well) compared with 16 healthy subjects at high risk (13+/-4/well, P<0.05) or 14 at low risk (22+/-3/well, P<0.001) for CAD. G-CSF 10 microg/kg per day for 5 days increased CD34(+)/CD133(+) cells from 0.5+/-0.2/microL to 59.5+/-10.6/microL and CD133(+)/ VEGFR-2(+) cells from 0.007+/-0.004/microL to 1.9+/-0.6/microL (both P<0.001). Also increased were CD133(+) cells that coexpressed the homing receptor CXCR4 (30.4+/-8.3/microL, P<0.05). Endothelial cell-forming clusters in 10 patients increased to 27+/-9/well after treatment (P<0.05), with a decline to 9+/-4/well at 2 weeks (P=0.06). Despite reduced EPCs compared with healthy controls, patients with CAD respond to G-CSF with increases in EPC number and homing receptor expression in the circulation and endothelial out-growth in culture. Endothelial progenitor cells (EPCs) are reduced in coronary artery disease. Granulocyte colony-stimulating factor (CSF) administered to patients increased: (1) CD133+/VEGFR-2+ cells consistent with EPC phenotype; (2) CD133+ cells coexpressing the chemokine receptor CXCR4, important for homing of EPCs to ischemic tissue; and (3) endothelial cell-forming clusters in culture. Whether EPCs mobilized into the circulation will be useful for the purpose of initiating vascular growth and myocyte repair

Effect of onion peel extract on endothelial function and endothelial progenitor cells in overweight and obese individuals.

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Choi, Eun-Yong; Lee, Hansongyi; Woo, Jong Shin; Jang, Hyun Hee; Hwang, Seung Joon; Kim, Hyun Soo; Kim, Woo-Sik; Kim, Young-Seol; Choue, Ryowon; Cha, Yong-Jun; Yim, Jung-Eun; Kim, Weon

2015-09-01

Acute or chronic intake of polyphenol-rich foods has been reported to improve endothelial function. Quercetin, found abundantly in onion, is a potent antioxidant flavonoid. The aim of this study was to investigate whether consumption of onion peel extract (OPE) improves endothelial function in healthy overweight and obese individuals. This was a randomized double-blind, placebo-controlled study. Seventy-two healthy overweight and obese participants were randomly assigned to receive a red, soft capsule of OPE (100 mg quercetin/d, 50 mg quercetin twice daily; n = 36 participants) or an identical placebo capsule (n = 36) for 12 wk. Endothelial function, defined by flow-mediated dilation (FMD), circulating endothelial progenitor cells (EPCs) by flow cytometry, and laboratory test were determined at baseline and after treatment. Baseline characteristics and laboratory findings did not significantly differ between the two groups. Compared with baseline values, the OPE group showed significantly improved FMD at 12 wk (from 12.5 ± 5.2 to 15.2 ± 6.1; P = 0.002), whereas the placebo group showed no difference. Nitroglycerin-mediated dilation did not change in either group. EPC counts (44.2 ± 25.6 versus 52.3 ± 18.6; P = 0.005) and the percentage of EPCs were significantly increased in the OPE group. When FMD was divided into quartiles, rate of patients with endothelial dysfunction defined as lowest quartile (cutoff value, 8.6%) of FMD improved from 26% to 9% by OPE. Medium-term administration of OPE an improvement in FMD and circulating EPCs. Copyright © 2015 Elsevier Inc. All rights reserved.

Comparison of endothelial progenitor cells in Parkinson's disease patients treated with levodopa and levodopa/COMT inhibitor.

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Phil Hyu Lee

Full Text Available BACKGROUND: Levodopa treatment in Parkinson's disease (PD increases in serum homocysteine levels due to its metabolism via catechol O-methyltransferase. Endothelial progenitor cells (EPCs have the capacity to differentiate into mature endothelial cells and are markers for endothelial functions and cardiovascular risks. Along with traditional vascular risk factors, hyperhomocysteinemia is known to decrease the level of EPCs. In the present study, we hypothesized that that levodopa-induced hyperhomocysteinemia leads to a change in EPC levels. METHODOLOGY/PRINCIPAL FINDINGS: We prospectively enrolled PD patients who had been prescribed either levodopa/carbidopa (PD-L group, n = 28 or levodopa/carbidopa/COMT inhibitor (PD-LC group, n = 25 for more than 1 year. The number of circulating EPCs was measured by flow cytometry using dual staining of anti-CD34 and anti-KDR antibodies. The EPCs were divided into tertiles based on their distributions and a logistic regression analysis was used to estimate independent predictors of the highest tertile of EPCs. The number of endothelial progenitor cells was significantly decreased in PD-L patients (118±99/mL compared with either PD-LC patients (269±258/mL, p = 0.007 or controls (206±204/mL, p = 0.012. The level of homocysteine was significantly increased in PD-L patients (14.9±5.3 µmol/L compared with either PD-LC patients (11.9±3.0 µmol/L, p = 0.028 or controls (11.1±2.5 µmol/L, p = 0.012. The level of homocysteine was negatively correlated with endothelial progenitor cell levels (r = -0.252, p = 0.028 and was an independent predictor of the highest tertile of endothelial progenitor cell levels (OR; 0.749 [95% CI: 0.584-0.961]. CONCLUSIONS/SIGNIFICANCE: These data indicate that a higher consumption of EPC for restoration of endothelial damage may be associated with chronic levodopa treatment in PD patients.

Bone marrow endothelial progenitors augment atherosclerotic plaque regression in a mouse model of plasma lipid lowering

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Yao, Longbiao; Heuser-Baker, Janet; Herlea-Pana, Oana; Iida, Ryuji; Wang, Qilong; Zou, Ming-Hui; Barlic-Dicen, Jana

2012-01-01

The major event initiating atherosclerosis is hypercholesterolemia-induced disruption of vascular endothelium integrity. In settings of endothelial damage, endothelial progenitor cells (EPCs) are mobilized from bone marrow into circulation and home to sites of vascular injury where they aid endothelial regeneration. Given the beneficial effects of EPCs in vascular repair, we hypothesized that these cells play a pivotal role in atherosclerosis regression. We tested our hypothesis in the atherosclerosis-prone mouse model in which hypercholesterolemia, one of the main factors affecting EPC homeostasis, is reversible (Reversa mice). In these mice normalization of plasma lipids decreased atherosclerotic burden; however, plaque regression was incomplete. To explore whether endothelial progenitors contribute to atherosclerosis regression, bone marrow EPCs from a transgenic strain expressing green fluorescent protein under the control of endothelial cell-specific Tie2 promoter (Tie2-GFP+) were isolated. These cells were then adoptively transferred into atheroregressing Reversa recipients where they augmented plaque regression induced by reversal of hypercholesterolemia. Advanced plaque regression correlated with engraftment of Tie2-GFP+ EPCs into endothelium and resulted in an increase in atheroprotective nitric oxide and improved vascular relaxation. Similarly augmented plaque regression was also detected in regressing Reversa mice treated with the stem cell mobilizer AMD3100 which also mobilizes EPCs to peripheral blood. We conclude that correction of hypercholesterolemia in Reversa mice leads to partial plaque regression that can be augmented by AMD3100 treatment or by adoptive transfer of EPCs. This suggests that direct cell therapy or indirect progenitor cell mobilization therapy may be used in combination with statins to treat atherosclerosis. PMID:23081735

A PEDF-Derived Peptide Inhibits Retinal Neovascularization and Blocks Mobilization of Bone Marrow-Derived Endothelial Progenitor Cells

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Richard Longeras

2012-01-01

Full Text Available Proliferative diabetic retinopathy is characterized by pathological retinal neovascularization, mediated by both angiogenesis (involving mature endothelial cells and vasculogenesis (involving bone marrow-derived circulating endothelial progenitor cells (EPCs. Pigment epithelium-derived factor (PEDF contains an N-terminal 34-amino acid peptide (PEDF-34 that has antiangiogenic properties. Herein, we present a novel finding that PEDF-34 also possesses antivasculogenic activity. In the oxygen-induced retinopathy (OIR model using transgenic mice that have Tie2 promoter-driven GFP expression, we quantified Tie2GFP+ cells in bone marrow and peripheral blood by fluorescence-activated cell sorting (FACS. OIR significantly increased the number of circulating Tie2-GFP+ at P16, correlating with the peak progression of neovascularization. Daily intraperitoneal injections of PEDF-34 into OIR mice decreased the number of Tie2-GFP+ cells in the circulation at P16 by 65% but did not affect the number of Tie2-GFP+ cells in the bone marrow. These studies suggest that PEDF-34 attenuates EPC mobilization from the bone marrow into the blood circulation during retinal neovascularization.

Effects of simvastatin/ezetimibe on microparticles, endothelial progenitor cells and platelet aggregation in subjects with coronary heart disease under antiplatelet therapy

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Camargo, L.M.; França, C.N.; Izar, M.C.; Bianco, H.T.; Lins, L.S.; Barbosa, S.P.; Pinheiro, L.F.; Fonseca, F.A.H. [Universidade Federal de São Paulo, Escola Paulista de Medicina, Departamento de Medicina, São Paulo, SP, Brasil, Departamento de Medicina, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP (Brazil)

2014-04-15

It is not known whether the addition of ezetimibe to statins adds cardiovascular protection beyond the expected changes in lipid levels. Subjects with coronary heart disease were treated with four consecutive 1-week courses of therapy (T) and evaluations. The courses were: T1, 100 mg aspirin alone; T2, 100 mg aspirin and 40 mg simvastatin/10 mg ezetimibe; T3, 40 mg simvastatin/10 mg ezetimibe, and 75 mg clopidogrel (300 mg initial loading dose); T4, 75 mg clopidogrel alone. Platelet aggregation was examined in whole blood. Endothelial microparticles (CD51), platelet microparticles (CD42/CD31), and endothelial progenitor cells (CD34/CD133; CDKDR/CD133, or CD34/KDR) were quantified by flow cytometry. Endothelial function was examined by flow-mediated dilation. Comparisons between therapies revealed differences in lipids (T2 and T3endothelial function (T2>T1 and T4, P=0.001). Decreased platelet aggregation was observed after aspirin (arachidonic acid, T1circulating endothelial and platelet microparticles, or endothelial progenitor cells. Cardiovascular protection following therapy with simvastatin/ezetimibe seems restricted to lipid changes and improvement of endothelial function not affecting the release of microparticles, mobilization of endothelial progenitor cells or decreased platelet aggregation.

Effects of simvastatin/ezetimibe on microparticles, endothelial progenitor cells and platelet aggregation in subjects with coronary heart disease under antiplatelet therapy

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Camargo, L.M.; França, C.N.; Izar, M.C.; Bianco, H.T.; Lins, L.S.; Barbosa, S.P.; Pinheiro, L.F.; Fonseca, F.A.H.

2014-01-01

It is not known whether the addition of ezetimibe to statins adds cardiovascular protection beyond the expected changes in lipid levels. Subjects with coronary heart disease were treated with four consecutive 1-week courses of therapy (T) and evaluations. The courses were: T1, 100 mg aspirin alone; T2, 100 mg aspirin and 40 mg simvastatin/10 mg ezetimibe; T3, 40 mg simvastatin/10 mg ezetimibe, and 75 mg clopidogrel (300 mg initial loading dose); T4, 75 mg clopidogrel alone. Platelet aggregation was examined in whole blood. Endothelial microparticles (CD51), platelet microparticles (CD42/CD31), and endothelial progenitor cells (CD34/CD133; CDKDR/CD133, or CD34/KDR) were quantified by flow cytometry. Endothelial function was examined by flow-mediated dilation. Comparisons between therapies revealed differences in lipids (T2 and T3endothelial function (T2>T1 and T4, P=0.001). Decreased platelet aggregation was observed after aspirin (arachidonic acid, T1circulating endothelial and platelet microparticles, or endothelial progenitor cells. Cardiovascular protection following therapy with simvastatin/ezetimibe seems restricted to lipid changes and improvement of endothelial function not affecting the release of microparticles, mobilization of endothelial progenitor cells or decreased platelet aggregation

Endothelial progenitor cells physiology and metabolic plasticity in brain angiogenesis and blood-brain barrier modeling

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Natalia Malinovskaya

2016-12-01

Full Text Available Currently, there is a considerable interest to the assessment of blood-brain barrier (BBB development as a part of cerebral angiogenesis developmental program. Embryonic and adult angiogenesis in the brain is governed by the coordinated activity of endothelial progenitor cells, brain microvascular endothelial cells, and non-endothelial cells contributing to the establishment of the BBB (pericytes, astrocytes, neurons. Metabolic and functional plasticity of endothelial progenitor cells controls their timely recruitment, precise homing to the brain microvessels, and efficient support of brain angiogenesis. Deciphering endothelial progenitor cells physiology would provide novel engineering approaches to establish adequate microfluidically-supported BBB models and brain microphysiological systems for translational studies.

Effect of Low Level Ionizing Radiation on Endothelial Progenitor Cells in Atherosclerotic Patients with Lower Limb Ischemia

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Taha, E.F.S.

2013-01-01

Cardiovascular disease (CVD) remains the leading cause of morbidity and mortality throughout the developed world (Williamson et al., 2012). Coronary artery disease (CAD) or atherosclerotic heart disease is a chronic life-threatening disease, which characterized by reducing blood supply to the heart as a result of the accumulation of atheromatous plaques within the walls of the arteries supplying the myocardium. Progressive atherosclerosis in the coronary arteries may lead to intimal thickening and eventual artery occlusion. Coronary artery occlusion can cause acute myocardial ischemia as a result of reduced oxygen supply or increased oxygen demand (Luthje and Andreas, 2008). Convincing evidence indicates that atherosclerosis is associated with endothelial dysfunction at the early stage of the disease process (Chiang et al., 2012). The endothelium is a dynamic cell layer that represents a physiological barrier between circulating blood and the surrounding tissues. Impaired endothelial function is a critical event in the initiation of atherosclerotic plaque development and thus may lead to vasoconstriction, vascular smooth muscle proliferation, hypercoagulability, thrombosis, and eventually, adverse cardiovascular events (Berger and Lavie, 2011). Asahara et al., (1997) described endothelial progenitor cells (EPC) in human peripheral blood. EPC are immature endothelial circulating cells mobilized from the bone marrow. These cells are involved in Introduction and aim of the work repairing the damaged endothelium and in facilitating neovascularization after ischemia (Rouhl et al., 2008). The role of EPC in health and disease is not understood completely. Most studies of healthy subjects and patients with coronary artery disease (CAD) report that the number and function of circulating EPC decrease with age and with the presence of classical vascular risk factors (Fadini et al., 2007). Recent studies suggested that EPCs play an important role in the risk of vascular

Endothelial Progenitor Cells as Shuttle of Anticancer Agents.

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Laurenzana, Anna; Margheri, Francesca; Chillà, Anastasia; Biagioni, Alessio; Margheri, Giancarlo; Calorini, Lido; Fibbi, Gabriella; Del Rosso, Mario

2016-10-01

Cell therapies are treatments in which stem or progenitor cells are stimulated to differentiate into specialized cells able to home to and repair damaged tissues. After their discovery, endothelial progenitor cells (EPCs) stimulated worldwide interest as possible vehicles to perform autologous cell therapy of tumors. Taking into account the tumor-homing properties of EPCs, two different approaches to control cancer progression have been pursued by combining cell-based therapy with gene therapy or with nanomedicine. The first approach is based on the possibility of engineering EPCs to express different transgenes, and the second is based on the capacity of EPCs to take up nanomaterials. Here we review the most important progress covering the following issues: the characterization of bona fide endothelial progenitor cells, their role in tumor vascularization and metastasis, and preclinical data about their use in cell-based tumor therapy, considering antiangiogenic, suicide, immune-stimulating, and oncolytic virus gene therapy. The mixed approach of EPC cell therapy and nanomedicine is discussed in terms of plasmonic-dependent thermoablation and molecular imaging.

The non-alcoholic fraction of beer increases stromal cell derived factor 1 and the number of circulating endothelial progenitor cells in high cardiovascular risk subjects: a randomized clinical trial.

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Chiva-Blanch, Gemma; Condines, Ximena; Magraner, Emma; Roth, Irene; Valderas-Martínez, Palmira; Arranz, Sara; Casas, Rosa; Martínez-Huélamo, Miriam; Vallverdú-Queralt, Anna; Quifer-Rada, Paola; Lamuela-Raventos, Rosa M; Estruch, Ramon

2014-04-01

Moderate alcohol consumption is associated with a decrease in cardiovascular risk, but fermented beverages seem to confer greater cardiovascular protection due to their polyphenolic content. Circulating endothelial progenitor cells (EPC) are bone-marrow-derived stem cells with the ability to repair and maintain endothelial integrity and function and are considered as a surrogate marker of vascular function and cumulative cardiovascular risk. Nevertheless, no study has been carried out on the effects of moderate beer consumption on the number of circulating EPC in high cardiovascular risk patients. To compare the effects of moderate consumption of beer, non-alcoholic beer and gin on the number of circulating EPC and EPC-mobilizing factors. In this crossover trial, 33 men at high cardiovascular risk were randomized to receive beer (30 g alcohol/d), the equivalent amount of polyphenols in the form of non-alcoholic beer, or gin (30 g alcohol/d) for 4 weeks. Diet and physical exercise were carefully monitored. The number of circulating EPC and EPC-mobilizing factors were determined at baseline and after each intervention. After the beer and non-alcoholic beer interventions, the number of circulating EPC significantly increased by 8 and 5 units, respectively, while no significant differences were observed after the gin period. In correlation, stromal cell derived factor 1 increased significantly after the non-alcoholic and the beer interventions. The non-alcoholic fraction of beer increases the number of circulating EPC in peripheral blood from high cardiovascular risk subjects. http://www.controlled-trials.com/ISRCTN95345245 ISRCTN95345245. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Folic acid supplementation normalizes the endothelial progenitor cell transcriptome of patients with type 1 diabetes: a case-control pilot study

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Stubbs Andrew

2009-08-01

Full Text Available Abstract Background Endothelial progenitor cells play an important role in vascular wall repair. Patients with type 1 diabetes have reduced levels of endothelial progenitor cells of which their functional capacity is impaired. Reduced nitric oxide bioavailability and increased oxidative stress play a role in endothelial progenitor cell dysfunction in these patients. Folic acid, a B-vitamin with anti-oxidant properties, may be able to improve endothelial progenitor cell function. In this study, we investigated the gene expression profiles of endothelial progenitor cells from patients with type 1 diabetes compared to endothelial progenitor cells from healthy subjects. Furthermore, we studied the effect of folic acid on gene expression profiles of endothelial progenitor cells from patients with type 1 diabetes. Methods We used microarray analysis to investigate the gene expression profiles of endothelial progenitor cells from type 1 diabetes patients before (n = 11 and after a four week period of folic acid supplementation (n = 10 compared to the gene expression profiles of endothelial progenitor cells from healthy subjects (n = 11. The probability of genes being differentially expressed among the classes was computed using a random-variance t-test. A multivariate permutation test was used to identify genes that were differentially expressed among the two classes. Functional classification of differentially expressed genes was performed using the biological process ontology in the Gene Ontology database. Results Type 1 diabetes significantly modulated the expression of 1591 genes compared to healthy controls. These genes were found to be involved in processes regulating development, cell communication, cell adhesion and localization. After folic acid treatment, endothelial progenitor cell gene expression profiles from diabetic patients were similar to those from healthy controls. Genes that were normalized by folic acid played a prominent role in

Endothelial progenitor cell-based neovascularization : implications for therapy

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Krenning, Guido; van Luyn, Marja J. A.; Harmsen, Martin C.

Ischemic cardiovascular events are a major cause of death globally. Endothelial progenitor cell (EPC)-based approaches can result in improvement of vascular perfusion and might offer clinical benefit. However, although functional improvement is observed, the lack of long-term engraftment of EPCs

Treating fat grafts with human endothelial progenitor cells promotes their vascularization and improves their survival in diabetes mellitus.

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Hamed, Saher; Ben-Nun, Ohad; Egozi, Dana; Keren, Aviad; Malyarova, Nastya; Kruchevsky, Danny; Gilhar, Amos; Ullmann, Yehuda

2012-10-01

Bone marrow-derived endothelial progenitor cells are required for vascularization of a fat graft to form a functional microvasculature within the graft and to facilitate its integration into the surrounding tissues. Organ transplantation carries a high risk of graft loss and rejection in patients with diabetes mellitus because endothelial progenitor cell function is impaired. The authors investigated the influence of endothelial progenitor cell treatment on the phenotype and survival of human fat grafts in immunocompromised mice with experimentally induced diabetes mellitus. The authors injected 1 ml of human fat tissue into the scalps of 14 nondiabetic and 28 diabetic immunocompromised mice, and then treated some of the grafts with endothelial progenitor cells that was isolated from the blood of a human donor. The phenotype of the endothelial progenitor cell-treated fat grafts from the 14 diabetic mice was compared with that of the untreated fat grafts from 14 nondiabetic and 14 diabetic mice, 18 days and 15 weeks after fat transplantation. Determination of graft phenotype included measurements of weight and volume, vascular endothelial growth factor levels, vascular endothelial growth factor receptor-2, endothelial nitric oxide synthase, and caspase 3 expression levels, and histologic analysis of the extent of vascularization. The untreated grafts from the diabetic mice were fully resorbed 15 weeks after fat transplantation. The phenotype of endothelial progenitor cell-treated fat grafts from the diabetic mice was similar to that of the untreated fat grafts from the nondiabetic mice. Endothelial progenitor cell treatment of transplanted fat can increase the survival of a fat graft by inducing its vascularization and decreasing the extent of apoptosis.

Endothelial progenitor cell mobilization and increased intravascular nitric oxide in patients undergoing cardiac rehabilitation.

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Paul, Jonathan D; Powell, Tiffany M; Thompson, Michael; Benjamin, Moshe; Rodrigo, Maria; Carlow, Andrea; Annavajjhala, Vidhya; Shiva, Sruti; Dejam, Andre; Gladwin, Mark T; McCoy, J Philip; Zalos, Gloria; Press, Beverly; Murphy, Mandy; Hill, Jonathan M; Csako, Gyorgy; Waclawiw, Myron A; Cannon, Richard O

2007-01-01

We investigated whether cardiac rehabilitation participation increases circulating endothelial progenitor cells (EPCs) and benefits vasculature in patients already on stable therapy previously shown to augment EPCs and improve endothelial function. Forty-six of 50 patients with coronary artery disease completed a 36-session cardiac rehabilitation program: 45 were treated with HMG-CoA reductase inhibitor (statin) therapy > or = 1 month (average baseline low-density lipoprotein cholesterol = 81 mg/dL). Mononuclear cells isolated from blood were quantified for EPCs by flow cytometry (CD133/VEGFR-2 cells) and assayed in culture for EPC colony-forming units (CFUs). In 23 patients, EPCs were stained for annexin-V as a marker of apoptosis, and nitrite was measured in blood as an indicator of intravascular nitric oxide. Endothelial progenitor cells increased from 35 +/- 5 to 63 +/- 10 cells/mL, and EPC-CFUs increased from 0.9 +/- 0.2 to 3.1 +/- 0.6 per well (both P < .01), but 11 patients had no increase in either measure. Those patients whose EPCs increased from baseline showed significant increases in nitrite and reduction in annexin-V staining (both P < .01) versus no change in patients without increase in EPCs. Over the course of the program, EPCs increased prior to increase in nitrite in the blood. Cardiac rehabilitation in patients receiving stable statin therapy and with low-density lipoprotein cholesterol at goal increases EPC number, EPC survival, and endothelial differentiation potential, associated with increased nitric oxide in the blood. Although this response was observed in most patients, a significant minority showed neither EPC mobilization nor increased nitric oxide in the blood.

Bone marrow endothelial progenitors in atherosclerotic plaque resolution

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Yao, Longbiao; Heuser-Baker, Janet; Herlea-Pana, Oana; Barlic-Dicen, Jana

2013-01-01

Atherosclerosis is a major cause of morbidity and mortality in the United States. Persistently elevated circulating low-density lipoprotein, or hypercholesterolemia, and deposition of low-density lipoprotein in the vascular wall are the main inducers of atherosclerosis, which manifests itself as arterial lesions or plaques. Some plaques become thrombosis-prone and rupture, causing acute myocardial infarction or stroke. Lowering plasma cholesterol through the use of statins is the primary intervention against atherosclerosis. Treatment with statins slows progression of atherosclerosis but can only support limited plaque regression. Partially regressed plaques continue to pose a serious threat due to their remaining potential to rupture. Thus, new interventions inducing complete reversal of atherosclerosis are being sought. Implementation of new therapies will require clear understanding of the mechanisms driving plaque resolution. In this Commentary, we highlight the role of bone marrow endothelial progenitors in atherosclerotic plaque regression and discuss how regenerative cell-based interventions could be used in combination with plasma lipid-lowering to induce plaque reversal in order to prevent and/or reduce adverse cardiovascular events. PMID:23538778

The effects of smoking on levels of endothelial progenitor cells and microparticles in the blood of healthy volunteers.

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Fariborz Mobarrez

Full Text Available BACKGROUND: Cigarette smoking, both active and passive, is one of the leading causes of morbidity and mortality in cardiovascular disease. To assess the impact of brief smoking on the vasculature, we determined levels of circulating endothelial progenitor cells (EPCs and circulating microparticles (MPs following the smoking of one cigarette by young, healthy intermittent smokers. MATERIALS AND METHODS: 12 healthy volunteers were randomized to either smoking or not smoking in a crossover fashion. Blood sampling was performed at baseline, 1, 4 and 24 hours following smoking/not smoking. The numbers of EPCs and MPs were determined by flow cytometry. MPs were measured from platelets, leukocytes and endothelial cells. Moreover, MPs were also labelled with anti-HMGB1 and SYTO 13 to assess the content of nuclear molecules. RESULTS: Active smoking of one cigarette caused an immediate and significant increase in the numbers of circulating EPCs and MPs of platelet-, endothelial- and leukocyte origin. Levels of MPs containing nuclear molecules were increased, of which the majority were positive for CD41 and CD45 (platelet- and leukocyte origin. CD144 (VE-cadherin or HMGB1 release did not significantly change during active smoking. CONCLUSION: Brief active smoking of one cigarette generated an acute release of EPC and MPs, of which the latter contained nuclear matter. Together, these results demonstrate acute effects of cigarette smoke on endothelial, platelet and leukocyte function as well as injury to the vascular wall.

Effects of Hypoglycemia on Circulating Stem and Progenitor Cells in Diabetic Patients.

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Fadini, Gian Paolo; Boscari, Federico; Cappellari, Roberta; Galasso, Silvia; Rigato, Mauro; Bonora, Benedetta Maria; D'Anna, Marianna; Bruttomesso, Daniela; Avogaro, Angelo

2018-03-01

Iatrogenic hypoglycemia is the most common acute diabetic complication, and it significantly increases morbidity. In people with diabetes, reduction in the levels of circulating stem and progenitor cells predicts adverse outcomes. To evaluate whether hypoglycemia in diabetes affects circulating stem cells and endothelial progenitor cells (EPCs). We performed an experimental hypoglycemia study (Study 1) and a case-control study (Study 2). Tertiary referral inpatient clinic. Type 1 diabetic patients (Study 1, n = 19); diabetic patients hospitalized for severe iatrogenic hypoglycemia, matched inpatient and outpatient controls (Study 2, n = 22/group). Type 1 diabetic patients underwent two in-hospital sessions of glucose monitoring during a breakfast meal with or without induction of hypoglycemia in random order. In Study 2, patients hospitalized for hypoglycemia and matched controls were compared. Circulating stem cells and EPCs were measured by flow cytometry based on the expression of CD34 and kinase insert domain receptor (KDR). In Study 1, the physiologic decline of CD34+KDR+ EPCs from 8 am to 2 pm was abolished by insulin-induced hypoglycemia in type 1 diabetic patients. In Study 2, diabetic patients hospitalized for severe iatrogenic hypoglycemia had significantly lower levels of CD34+ stem cells and CD34+KDR+ EPCs compared with diabetic inpatients or outpatient controls. In diabetic patients, a single mild hypoglycemic episode can compromise the physiologic EPC fluctuation, whereas severe hypoglycemia is associated with a marked reduction in stem cells and EPCs. These data provide a possible link between hypoglycemia and adverse outcomes of diabetes.

High-intensity Interval training enhances mobilization/functionality of endothelial progenitor cells and depressed shedding of vascular endothelial cells undergoing hypoxia.

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Tsai, Hsing-Hua; Lin, Chin-Pu; Lin, Yi-Hui; Hsu, Chih-Chin; Wang, Jong-Shyan

2016-12-01

Exercise training improves endothelium-dependent vasodilation, whereas hypoxic stress causes vascular endothelial dysfunction. Monocyte-derived endothelial progenitor cells (Mon-EPCs) contribute to vascular repair process by differentiating into endothelial cells. This study investigates how high-intensity interval (HIT) and moderate-intensity continuous (MCT) exercise training affect circulating Mon-EPC levels and EPC functionality under hypoxic condition. Sixty healthy sedentary males were randomized to engage in either HIT (3-min intervals at 40 and 80 % VO 2max for five repetitions, n = 20) or MCT (sustained 60 % VO 2max , n = 20) for 30 min/day, 5 days/week for 6 weeks, or to a control group (CTL) that did not received exercise intervention (n = 20). Mon-EPC characteristics and EPC functionality under hypoxic exercise (HE, 100 W under 12 % O 2 ) were determined before and after HIT, MCT, and CTL. The results demonstrated that after the intervention, the HIT group exhibited larger improvements in VO 2peak , estimated peak cardiac output (Q C ), and estimated peak perfusions of frontal cerebral lobe (Q FC ) and vastus lateralis (Q VL ) than the MCT group. Furthermore, HIT (a) increased circulating CD14 ++ /CD16 - /CD34 + /KDR + (Mon-1 EPC) and CD14 ++ /CD16 + /CD34 + /KDR + (Mon-2 EPC) cell counts, (b) promoted the migration and tube formation of EPCs, (c) diminished the shedding of endothelial (CD34 - /KDR + /phosphatidylserine + ) cells, and (d) elevated plasma nitrite plus nitrate, stromal cell-derived factor-1, matrix metalloproteinase-9, and vascular endothelial growth factor-A concentrations at rest or following HE, compared to those of MCT. In addition, Mon-1 and -2 EPC counts were directly related to VO 2peak and estimated peak Q C , Q FC , and Q VL . HIT is superior to MCT for improving hemodynamic adaptation and Mon-EPC production. Moreover, HIT effectively enhances EPC functionality and suppresses endothelial injury undergoing hypoxia.

Progenitor cells in pulmonary vascular remodeling

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Yeager, Michael E.; Frid, Maria G.; Stenmark, Kurt R.

2011-01-01

Pulmonary hypertension is characterized by cellular and structural changes in the walls of pulmonary arteries. Intimal thickening and fibrosis, medial hypertrophy and fibroproliferative changes in the adventitia are commonly observed, as is the extension of smooth muscle into the previously non-muscularized vessels. A majority of these changes are associated with the enhanced presence of α-SM-actin+ cells and inflammatory cells. Atypical abundances of functionally distinct endothelial cells, particularly in the intima (plexiform lesions), and also in the perivascular regions, are also described. At present, neither the origin(s) of these cells nor the molecular mechanisms responsible for their accumulation, in any of the three compartments of the vessel wall, have been fully elucidated. The possibility that they arise from either resident vascular progenitors or bone marrow–derived progenitor cells is now well established. Resident vascular progenitor cells have been demonstrated to exist within the vessel wall, and in response to certain stimuli, to expand and express myofibroblastic, endothelial or even hematopoietic markers. Bone marrow–derived or circulating progenitor cells have also been shown to be recruited to sites of vascular injury and to assume both endothelial and SM-like phenotypes. Here, we review the data supporting the contributory role of vascular progenitors (including endothelial progenitor cells, smooth muscle progenitor cells, pericytes, and fibrocytes) in vascular remodeling. A more complete understanding of the processes by which progenitor cells modulate pulmonary vascular remodeling will undoubtedly herald a renaissance of therapies extending beyond the control of vascular tonicity and reduction of pulmonary artery pressure. PMID:22034593

Biology and flow cytometry of proangiogenic hematopoietic progenitors cells.

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Rose, Jonathan A; Erzurum, Serpil; Asosingh, Kewal

2015-01-01

During development, hematopoiesis and neovascularization are closely linked to each other via a common bipotent stem cell called the hemangioblast that gives rise to both hematopoietic cells and endothelial cells. In postnatal life, this functional connection between the vasculature and hematopoiesis is maintained by a subset of hematopoietic progenitor cells endowed with the capacity to differentiate into potent proangiogenic cells. These proangiogenic hematopoietic progenitors comprise a specific subset of bone marrow (BM)-derived cells that homes to sites of neovascularization and possess potent paracrine angiogenic activity. There is emerging evidence that this subpopulation of hematopoietic progenitors plays a critical role in vascular health and disease. Their angiogenic activity is distinct from putative "endothelial progenitor cells" that become structural cells of the endothelium by differentiation into endothelial cells. Proangiogenic hematopoietic progenitor cell research requires multidisciplinary expertise in flow cytometry, hematology, and vascular biology. This review provides a comprehensive overview of proangiogenic hematopoietic progenitor cell biology and flow cytometric methods to detect these cells in the peripheral blood circulation and BM. © 2014 International Society for Advancement of Cytometry.

Human endothelial progenitor cells rescue cortical neurons from oxygen-glucose deprivation induced death.

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Bacigaluppi, Susanna; Donzelli, Elisabetta; De Cristofaro, Valentina; Bragazzi, Nicola Luigi; D'Amico, Giovanna; Scuteri, Arianna; Tredici, Giovanni

2016-09-19

Cerebral ischemia is characterized by both acute and delayed neuronal injuries. Neuro-protection is a major issue that should be properly addressed from a pharmacological point of view, and cell-based treatment approaches are of interest due to their potential pleiotropic effects. Endothelial progenitor cells have the advantage of being mobilized from the bone marrow into the circulation, but have been less studied than other stem cells, such as mesenchymal stem cells. Therefore, the comparison between human endothelial progenitor cells (hEPC) and human mesenchymal progenitor cells (hMSC) in terms of efficacy in rescuing neurons from cell death after transitory ischemia is the aim of the current study, in the effort to address further directions. In vitro model of oxygen-glucose deprivation (OGD) on a primary culture of rodent cortical neurons was set up with different durations of exposure: 1, 2 and 3hrs with assessment of neuron survival. The 2hrs OGD was chosen for the subsequent experiments. After 2hrs OGD neurons were either placed in indirect co-culture with hMSC or hEPC or cultured in hMSC or hEPC conditioned medium and cell viability was evaluated by MTT assay. At day 2 after 2hrs OGD exposure, mean neuronal survival was 47.9±24.2%. In contrast, after treatment with hEPC and hMSC indirect co-culture was 74.1±27.3%; and 69.4±18.8%, respectively. In contrast, treatment with conditioned medium did not provide any advantage in terms of survival to OGD neurons The study shows the efficacy of hEPC in indirect co-culture to rescue neurons from cell death after OGD, comparable to that of hMSC. hEPC deserve further studies given their potential interest for ischemia. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Circulating endothelial progenitor cells do not contribute to regeneration of endothelium after murine arterial injury

DEFF Research Database (Denmark)

Hagensen, Mette; Raarup, Merete Krog; Mortensen, Martin Bødtker

2012-01-01

into endothelial cells (ECs). We tested this theory in a murine arterial injury model using carotid artery transplants and fluorescent reporter mice. METHODS AND RESULTS: Wire-injured carotid artery segments from wild-type mice were transplanted into TIE2-GFP transgenic mice expressing green fluorescent protein...... (GFP) in ECs. We found that the endothelium regenerated with GFP(+) ECs as a function of time, evolving from the anastomosis sites towards the centre of the transplant. A migration front of ECs at Day 7 was verified by scanning electron microscopy and by bright-field microscopy using recipient TIE2-lac......Z mice with endothelial β-galactosidase expression. These experiments indicated migration of flanking ECs rather than homing of circulating cells as the underlying mechanism. To confirm this, we interposed non-injured wild-type carotid artery segments between the denuded transplant and the TIE2-GFP...

Characterization of vascular endothelial progenitor cells from chicken bone marrow

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Bai Chunyu

2012-05-01

Full Text Available Abstract Background Endothelial progenitor cells (EPC are a type of stem cell used in the treatment of atherosclerosis, vascular injury and regeneration. At present, most of the EPCs studied are from human and mouse, whereas the study of poultry-derived EPCs has rarely been reported. In the present study, chicken bone marrow-derived EPCs were isolated and studied at the cellular level using immunofluorescence and RT-PCR. Results We found that the majority of chicken EPCs were spindle shaped. The growth-curves of chicken EPCs at passages (P 1, -5 and -9 were typically “S”-shaped. The viability of chicken EPCs, before and after cryopreservation was 92.2% and 81.1%, respectively. Thus, cryopreservation had no obvious effects on the viability of chicken EPCs. Dil-ac-LDL and FITC-UAE-1 uptake assays and immunofluorescent detection of the cell surface markers CD34, CD133, VEGFR-2 confirmed that the cells obtained in vitro were EPCs. Observation of endothelial-specific Weibel-Palade bodies using transmission electron microscopy further confirmed that the cells were of endothelial lineage. In addition, chicken EPCs differentiated into endothelial cells and smooth muscle cells upon induction with VEGF and PDGF-BB, respectively, suggesting that the chicken EPCs retained multipotency in vitro. Conclusions These results suggest that chicken EPCs not only have strong self-renewal capacity, but also the potential to differentiate into endothelial and smooth muscle cells. This research provides theoretical basis and experimental evidence for potential therapeutic application of endothelial progenitor cells in the treatment of atherosclerosis, vascular injury and diabetic complications.

Cilostazol activates function of bone marrow-derived endothelial progenitor cell for re-endothelialization in a carotid balloon injury model.

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Rie Kawabe-Yako

Full Text Available BACKGROUND: Cilostazol(CLZ has been used as a vasodilating anti-platelet drug clinically and demonstrated to inhibit proliferation of smooth muscle cells and effect on endothelial cells. However, the effect of CLZ on re-endothelialization including bone marrow (BM-derived endothelial progenitor cell (EPC contribution is unclear. We have investigated the hypothesis that CLZ might accelerate re-endothelialization with EPCs. METHODOLOGY/PRINCIPAL FINDINGS: Balloon carotid denudation was performed in male Sprague-Dawley rats. CLZ group was given CLZ mixed feed from 2 weeks before carotid injury. Control group was fed normal diet. CLZ accelerated re-endothelialization at 2 weeks after surgery and resulted in a significant reduction of neointima formation 4 weeks after surgery compared with that in control group. CLZ also increased the number of circulating EPCs throughout the time course. We examined the contribution of BM-derived EPCs to re-endothelialization by BM transplantation from Tie2/lacZ mice to nude rats. The number of Tie2-regulated X-gal positive cells on injured arterial luminal surface was increased at 2 weeks after surgery in CLZ group compared with that in control group. In vitro, CLZ enhanced proliferation, adhesion and migration activity, and differentiation with mRNA upregulation of adhesion molecule integrin αvβ3, chemokine receptor CXCR4 and growth factor VEGF assessed by real-time RT-PCR in rat BM-derived cultured EPCs. In addition, CLZ markedly increased the expression of SDF-1α that is a ligand of CXCR4 receptor in EPCs, in the media following vascular injury. CONCLUSIONS/SIGNIFICANCE: CLZ promotes EPC mobilization from BM and EPC recruitment to sites of arterial injury, and thereby inhibited neointima formation with acceleration of re-endothelialization with EPCs as well as pre-existing endothelial cells in a rat carotid balloon injury model. CLZ could be not only an anti-platelet agent but also a promising tool for

Characterization of Endothelial Progenitor Cell Interactions with Human Tropoelastin.

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Young Yu

Full Text Available The deployment of endovascular implants such as stents in the treatment of cardiovascular disease damages the vascular endothelium, increasing the risk of thrombosis and promoting neointimal hyperplasia. The rapid restoration of a functional endothelium is known to reduce these complications. Circulating endothelial progenitor cells (EPCs are increasingly recognized as important contributors to device re-endothelialization. Extracellular matrix proteins prominent in the vessel wall may enhance EPC-directed re-endothelialization. We examined attachment, spreading and proliferation on recombinant human tropoelastin (rhTE and investigated the mechanism and site of interaction. EPCs attached and spread on rhTE in a dose dependent manner, reaching a maximal level of 56±3% and 54±3%, respectively. EPC proliferation on rhTE was comparable to vitronectin, fibronectin and collagen. EDTA, but not heparan sulfate or lactose, reduced EPC attachment by 81±3%, while full attachment was recovered after add-back of manganese, inferring a classical integrin-mediated interaction. Integrin αVβ3 blocking antibodies decreased EPC adhesion and spreading on rhTE by 39±3% and 56±10% respectively, demonstrating a large contribution from this specific integrin. Attachment of EPCs on N-terminal rhTE constructs N25 and N18 accounted for most of this interaction, accompanied by comparable spreading. In contrast, attachment and spreading on N10 was negligible. αVβ3 blocking antibodies reduced EPC spreading on both N25 and N18 by 45±4% and 42±14%, respectively. In conclusion, rhTE supports EPC binding via an integrin mechanism involving αVβ3. N25 and N18, but not N10 constructs of rhTE contribute to EPC binding. The regulation of EPC activity by rhTE may have implications for modulation of the vascular biocompatibility of endovascular implants.

Exercise training improves in vivo endothelial repair capacity of early endothelial progenitor cells in subjects with metabolic syndrome.

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Sonnenschein, Kristina; Horváth, Tibor; Mueller, Maja; Markowski, Andrea; Siegmund, Tina; Jacob, Christian; Drexler, Helmut; Landmesser, Ulf

2011-06-01

Endothelial dysfunction and injury are considered to contribute considerably to the development and progression of atherosclerosis. It has been suggested that intense exercise training can increase the number and angiogenic properties of early endothelial progenitor cells (EPCs). However, whether exercise training stimulates the capacity of early EPCs to promote repair of endothelial damage and potential underlying mechanisms remain to be determined. The present study was designed to evaluate the effects of moderate exercise training on in vivo endothelial repair capacity of early EPCs, and their nitric oxide and superoxide production as characterized by electron spin resonance spectroscopy analysis in subjects with metabolic syndrome. Twenty-four subjects with metabolic syndrome were randomized to an 8 weeks exercise training or a control group. Superoxide production and nitric oxide (NO) availability of early EPCs were characterized by using electron spin resonance (ESR) spectroscopy analysis. In vivo endothelial repair capacity of EPCs was examined by transplantation into nude mice with defined carotid endothelial injury. Endothelium-dependent, flow-mediated vasodilation was analysed using high-resolution ultrasound. Importantly, exercise training resulted in a substantially improved in vivo endothelial repair capacity of early EPCs (24.0 vs 12.7%; p exercise training, but not in the control group. Moreover, exercise training reduced superoxide production of EPCs, which was not observed in the control group. The present study suggests for the first time that moderate exercise training increases nitric oxide production of early endothelial progenitor cells and reduces their superoxide production. Importantly, this is associated with a marked beneficial effect on the in vivo endothelial repair capacity of early EPCs in subjects with metabolic syndrome.

Androgen Modulates Functions of Endothelial Progenitor Cells through Activated Egr1 Signaling

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Yizhou Ye

2016-01-01

Full Text Available Researches show that androgens have important effects on migration of endothelial cells and endothelial protection in coronary heart disease. Endothelial progenitor cells (EPCs as a progenitor cell type that can differentiate into endothelial cells, have a critical role in angiogenesis and endothelial protection. The relationship between androgen and the functions of EPCs has animated much interest and controversy. In this study, we investigated the angiogenic and migratory functions of EPCs after treatment by dihydrotestosterone (DHT and the molecular mechanisms as well. We found that DHT treatment enhanced the incorporation of EPCs into tubular structures formed by HUVECs and the migratory activity of EPCs in the transwell assay dose dependently. Moreover, microarray analysis was performed to explore how DHT changes the gene expression profiles of EPCs. We found 346 differentially expressed genes in androgen-treated EPCs. Angiogenesis-related genes like Egr-1, Vcan, Efnb2, and Cdk2ap1 were identified to be regulated upon DHT treatment. Furthermore, the enhanced angiogenic and migratory abilities of EPCs after DHT treatment were inhibited by Egr1-siRNA transfection. In conclusion, our findings suggest that DHT markedly enhances the vessel forming ability and migration capacity of EPCs. Egr1 signaling may be a possible pathway in this process.

Levels of circulating CD45dimCD34+VEGFR2+ progenitor cells correlate with outcome in metastatic renal cell carcinoma patients treated with tyrosine kinase inhibitors

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Farace, F; Gross-Goupil, M; Tournay, E; Taylor, M; Vimond, N; Jacques, N; Billiot, F; Mauguen, A; Hill, C; Escudier, B

2011-01-01

Background: Predicting the efficacy of antiangiogenic therapy would be of clinical value in patients (pts) with metastatic renal cell carcinoma (mRCC). We tested the hypothesis that circulating endothelial cell (CEC), bone marrow-derived CD45dimCD34+VEGFR2+ progenitor cell or plasma angiogenic factor levels are associated with clinical outcome in mRCC pts undergoing treatment with tyrosine kinase inhibitors (TKI). Methods: Fifty-five mRCC pts were prospectively monitored at baseline (day 1) and day 14 during treatment (46 pts received sunitinib and 9 pts received sorafenib). Circulating endothelial cells (CD45−CD31+CD146+7-amino-actinomycin (7AAD)− cells) were measured in 1 ml whole blood using four-color flow cytometry (FCM). Circulating CD45dimCD34+VEGFR2+7AAD− progenitor cells were measured in progenitor-enriched fractions by four-color FCM. Plasma VEGF, sVEGFR2, SDF-1α and sVCAM-1 levels were determined by ELISA. Correlations between baseline CEC, CD45dimCD34+VEGFR2+7AAD− progenitor cells, plasma factors, as well as day 1–day 14 changes in CEC, CD45dimCD34+VEGFR2+7AAD− progenitor, plasma factor levels, and response to TKI, progression-free survival (PFS) and overall survival (OS) were examined. Results: No significant correlation between markers and response to TKI was observed. No association between baseline CEC, plasma VEGF, sVEGFR-2, SDF-1α, sVCAM-1 levels with PFS and OS was observed. However, baseline CD45dimCD34+VEGFR2+7AAD− progenitor cell levels were associated with PFS (P=0.01) and OS (P=0.006). Changes in this population and in SDF-1α levels between day 1 and day 14 were associated with PFS (P=0.03, P=0.002). Changes in VEGF and SDF-1α levels were associated with OS (P=0.02, P=0.007). Conclusion: Monitoring CD45dimCD34+VEGFR2+ progenitor cells, plasma VEGF and SDF-1α levels could be of clinical interest in TKI-treated mRCC pts to predict outcome. PMID:21386843

Tumor-derived circulating endothelial cell clusters in colorectal cancer.

KAUST Repository

Cima, Igor; Kong, Say Li; Sengupta, Debarka; Tan, Iain B; Phyo, Wai Min; Lee, Daniel; Hu, Min; Iliescu, Ciprian; Alexander, Irina; Goh, Wei Lin; Rahmani, Mehran; Suhaimi, Nur-Afidah Mohamed; Vo, Jess H; Tai, Joyce A; Tan, Joanna H; Chua, Clarinda; Ten, Rachel; Lim, Wan Jun; Chew, Min Hoe; Hauser, Charlotte; van Dam, Rob M; Lim, Wei-Yen; Prabhakar, Shyam; Lim, Bing; Koh, Poh Koon; Robson, Paul; Ying, Jackie Y; Hillmer, Axel M; Tan, Min-Han

2016-01-01

Clusters of tumor cells are often observed in the blood of cancer patients. These structures have been described as malignant entities for more than 50 years, although their comprehensive characterization is lacking. Contrary to current consensus, we demonstrate that a discrete population of circulating cell clusters isolated from the blood of colorectal cancer patients are not cancerous but consist of tumor-derived endothelial cells. These clusters express both epithelial and mesenchymal markers, consistent with previous reports on circulating tumor cell (CTC) phenotyping. However, unlike CTCs, they do not mirror the genetic variations of matched tumors. Transcriptomic analysis of single clusters revealed that these structures exhibit an endothelial phenotype and can be traced back to the tumor endothelium. Further results show that tumor-derived endothelial clusters do not form by coagulation or by outgrowth of single circulating endothelial cells, supporting a direct release of clusters from the tumor vasculature. The isolation and enumeration of these benign clusters distinguished healthy volunteers from treatment-naïve as well as pathological early-stage (≤IIA) colorectal cancer patients with high accuracy, suggesting that tumor-derived circulating endothelial cell clusters could be used as a means of noninvasive screening for colorectal cancer. In contrast to CTCs, tumor-derived endothelial cell clusters may also provide important information about the underlying tumor vasculature at the time of diagnosis, during treatment, and throughout the course of the disease.

Tumor-derived circulating endothelial cell clusters in colorectal cancer.

KAUST Repository

Cima, Igor

2016-06-29

Clusters of tumor cells are often observed in the blood of cancer patients. These structures have been described as malignant entities for more than 50 years, although their comprehensive characterization is lacking. Contrary to current consensus, we demonstrate that a discrete population of circulating cell clusters isolated from the blood of colorectal cancer patients are not cancerous but consist of tumor-derived endothelial cells. These clusters express both epithelial and mesenchymal markers, consistent with previous reports on circulating tumor cell (CTC) phenotyping. However, unlike CTCs, they do not mirror the genetic variations of matched tumors. Transcriptomic analysis of single clusters revealed that these structures exhibit an endothelial phenotype and can be traced back to the tumor endothelium. Further results show that tumor-derived endothelial clusters do not form by coagulation or by outgrowth of single circulating endothelial cells, supporting a direct release of clusters from the tumor vasculature. The isolation and enumeration of these benign clusters distinguished healthy volunteers from treatment-naïve as well as pathological early-stage (≤IIA) colorectal cancer patients with high accuracy, suggesting that tumor-derived circulating endothelial cell clusters could be used as a means of noninvasive screening for colorectal cancer. In contrast to CTCs, tumor-derived endothelial cell clusters may also provide important information about the underlying tumor vasculature at the time of diagnosis, during treatment, and throughout the course of the disease.

Multipotent embryonic isl1+ progenitor cells lead to cardiac, smooth muscle, and endothelial cell diversification.

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Moretti, Alessandra; Caron, Leslie; Nakano, Atsushi; Lam, Jason T; Bernshausen, Alexandra; Chen, Yinhong; Qyang, Yibing; Bu, Lei; Sasaki, Mika; Martin-Puig, Silvia; Sun, Yunfu; Evans, Sylvia M; Laugwitz, Karl-Ludwig; Chien, Kenneth R

2006-12-15

Cardiogenesis requires the generation of endothelial, cardiac, and smooth muscle cells, thought to arise from distinct embryonic precursors. We use genetic fate-mapping studies to document that isl1(+) precursors from the second heart field can generate each of these diverse cardiovascular cell types in vivo. Utilizing embryonic stem (ES) cells, we clonally amplified a cellular hierarchy of isl1(+) cardiovascular progenitors, which resemble the developmental precursors in the embryonic heart. The transcriptional signature of isl1(+)/Nkx2.5(+)/flk1(+) defines a multipotent cardiovascular progenitor, which can give rise to cells of all three lineages. These studies document a developmental paradigm for cardiogenesis, where muscle and endothelial lineage diversification arises from a single cell-level decision of a multipotent isl1(+) cardiovascular progenitor cell (MICP). The discovery of ES cell-derived MICPs suggests a strategy for cardiovascular tissue regeneration via their isolation, renewal, and directed differentiation into specific mature cardiac, pacemaker, smooth muscle, and endothelial cell types.

Characterization of a distinct population of circulating human non-adherent endothelial forming cells and their recruitment via intercellular adhesion molecule-3.

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Sarah L Appleby

Full Text Available Circulating vascular progenitor cells contribute to the pathological vasculogenesis of cancer whilst on the other hand offer much promise in therapeutic revascularization in post-occlusion intervention in cardiovascular disease. However, their characterization has been hampered by the many variables to produce them as well as their described phenotypic and functional heterogeneity. Herein we have isolated, enriched for and then characterized a human umbilical cord blood derived CD133(+ population of non-adherent endothelial forming cells (naEFCs which expressed the hematopoietic progenitor cell markers (CD133, CD34, CD117, CD90 and CD38 together with mature endothelial cell markers (VEGFR2, CD144 and CD31. These cells also expressed low levels of CD45 but did not express the lymphoid markers (CD3, CD4, CD8 or myeloid markers (CD11b and CD14 which distinguishes them from 'early' endothelial progenitor cells (EPCs. Functional studies demonstrated that these naEFCs (i bound Ulex europaeus lectin, (ii demonstrated acetylated-low density lipoprotein uptake, (iii increased vascular cell adhesion molecule (VCAM-1 surface expression in response to tumor necrosis factor and (iv in co-culture with mature endothelial cells increased the number of tubes, tubule branching and loops in a 3-dimensional in vitro matrix. More importantly, naEFCs placed in vivo generated new lumen containing vasculature lined by CD144 expressing human endothelial cells (ECs. Extensive genomic and proteomic analyses of the naEFCs showed that intercellular adhesion molecule (ICAM-3 is expressed on their cell surface but not on mature endothelial cells. Furthermore, functional analysis demonstrated that ICAM-3 mediated the rolling and adhesive events of the naEFCs under shear stress. We suggest that the distinct population of naEFCs identified and characterized here represents a new valuable therapeutic target to control aberrant vasculogenesis.

Characterization of a Distinct Population of Circulating Human Non-Adherent Endothelial Forming Cells and Their Recruitment via Intercellular Adhesion Molecule-3

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Thompson, Emma J.; Barrett, Jeffrey M.; Tooley, Katie; Sen, Shaundeep; Sun, Wai Yan; Grose, Randall; Nicholson, Ian; Levina, Vitalina; Cooke, Ira; Talbo, Gert; Lopez, Angel F.; Bonder, Claudine S.

2012-01-01

Circulating vascular progenitor cells contribute to the pathological vasculogenesis of cancer whilst on the other hand offer much promise in therapeutic revascularization in post-occlusion intervention in cardiovascular disease. However, their characterization has been hampered by the many variables to produce them as well as their described phenotypic and functional heterogeneity. Herein we have isolated, enriched for and then characterized a human umbilical cord blood derived CD133+ population of non-adherent endothelial forming cells (naEFCs) which expressed the hematopoietic progenitor cell markers (CD133, CD34, CD117, CD90 and CD38) together with mature endothelial cell markers (VEGFR2, CD144 and CD31). These cells also expressed low levels of CD45 but did not express the lymphoid markers (CD3, CD4, CD8) or myeloid markers (CD11b and CD14) which distinguishes them from ‘early’ endothelial progenitor cells (EPCs). Functional studies demonstrated that these naEFCs (i) bound Ulex europaeus lectin, (ii) demonstrated acetylated-low density lipoprotein uptake, (iii) increased vascular cell adhesion molecule (VCAM-1) surface expression in response to tumor necrosis factor and (iv) in co-culture with mature endothelial cells increased the number of tubes, tubule branching and loops in a 3-dimensional in vitro matrix. More importantly, naEFCs placed in vivo generated new lumen containing vasculature lined by CD144 expressing human endothelial cells (ECs). Extensive genomic and proteomic analyses of the naEFCs showed that intercellular adhesion molecule (ICAM)-3 is expressed on their cell surface but not on mature endothelial cells. Furthermore, functional analysis demonstrated that ICAM-3 mediated the rolling and adhesive events of the naEFCs under shear stress. We suggest that the distinct population of naEFCs identified and characterized here represents a new valuable therapeutic target to control aberrant vasculogenesis. PMID:23144795

The effect of angiotensin-2 receptor blocker valsartan on circulating level of endothelial progenitor cells in diabetic patients with asymptomatic coronary artery disease.

Science.gov (United States)

Berezin, Alexander E; Kremzer, Alexander A; Martovitskaya, Yulia V; Samura, Tatyana A

2015-01-01

Decreased circulating endothelial progenitor cells (EPCs) are considered as strong and robust biomarkers for the prediction of cardiovascular outcomes in diabetic populations. The perspectives for modulating EPCs levels in T2DM with known coronary artery disease (CAD) with different drugs, affected mechanisms of improving mobilization of EPCs from tissue, are not still understood. To evaluate an effect of angiotensin-2 receptor blocker valsartan on circulating level of EPCs in diabetic patients with asymptomatic CAD. The study population was structured retrospectively after determining the CAD by contrast-enhanced spiral computed tomography angiography in 126 asymptomatic subjects. All subjects were distributed into two cohorts depending on daily doses of valsartan given. Low (80-160 mg daily orally) and high doses (240-320 mg daily orally) of valsartan were used and they were adjusted depending on achieving BP level less than 140/80 mmHg. The change from baseline in CD34(+) subset cells (frequencies and absolute values) was not significantly different between treatment cohorts. We found a significant increase of circulating level of CD14(+)CD309(+) cells in two patient cohorts. But more prominent change of CD14(+)CD309(+) cells was verified in subjects who were given valsartan in high daily doses when compared with persons who were included into cohort with low daily doses of the drug (1.96% versus 2.59%, respectively; Pvalsartan only. We found positive influence of angiotensin-2 receptor blocker valsartan in escalation doses on bone marrow-derived EPCs phenotyped as CD14(+)CD309(+) and CD14(+)CD309(+)Tie(2+) in T2DM patients with known asymptomatic CAD. Copyright © 2014 Diabetes India. Published by Elsevier Ltd. All rights reserved.

Norepinephrine stimulates mobilization of endothelial progenitor cells after limb ischemia.

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Qijun Jiang

Full Text Available OBJECTIVE: During several pathological processes such as cancer progression, thermal injury, wound healing and hindlimb ischemia, the mobilization of endothelial progenitor cells (EPCs mobilization was enhanced with an increase of sympathetic nerve activity and norepinephrine (NE secretion, yet the cellular and molecular mechanisms involved in the effects of NE on EPCs has less been investigated. METHODS AND RESULTS: EPCs from BMs, peripheral circulation and spleens, the VEGF concentration in BM, skeletal muscle, peripheral circulation and spleen and angiogenesis in ischemic gastrocnemius were quantified in mice with hindlimbs ischemia. Systemic treatment of NE significantly increased EPCs number in BM, peripheral circulation and spleen, VEGF concentration in BM and skeletal muscle and angiogenesis in ischemic gastrocnemius in mice with hind limb ischemia, but did not affair VEGF concentration in peripheral circulation and spleen. EPCs isolated from healthy adults were cultured with NE in vitro to evaluate proliferation potential, migration capacity and phosphorylations of Akt and eNOS signal moleculars. Treatment of NE induced a significant increase in number of EPCs in the S-phase in a dose-dependent manner, as well as migrative activity of EPCs in vitro (p<0.05. The co-treatment of Phentolamine, I127, LY294002 and L-NAME with NE blocked the effects of NE on EPCs proliferation and migration. Treatment with NE significantly increased phosphorylation of Akt and eNOS of EPCs. Addition of phentolamine and I127 attenuated the activation of Akt/eNOS pathway, but metoprolol could not. Pretreatment of mice with either Phentolamine or I127 significantly attenuated the effects of NE on EPCs in vivo, VEGF concentration in BM, skeletal muscle and angiogenesis in ischemic gastrocnemius, but Metoprolol did not. CONCLUSION: These results unravel that sympathetic nervous system regulate EPCs mobilization and their pro-angiogenic capacity via α adrenoceptor

Endothelial progenitor cells (EPCs) in ageing and age-related diseases: How currently available treatment modalities affect EPC biology, atherosclerosis, and cardiovascular outcomes.

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Altabas, Velimir; Altabas, Karmela; Kirigin, Lora

2016-10-01

Endothelial progenitor cells (EPCs) are mononuclear cells that circulate in the blood and are derived from different tissues, expressing cell surface markers that are similar to mature endothelial cells. The discovery of EPCs has lead to new insights in vascular repair and atherosclerosis and also a new theory for ageing. EPCs from the bone marrow and some other organs aid in vascular repair by migrating to distant vessels where they differentiate into mature endothelial cells and replace old and injured endothelial cells. The ability of EPCs to repair vascular damage depends on their number and functionality. Currently marketed drugs used in a variety of diseases can modulate these characteristics. In this review, the effect of currently available treatment options for cardiovascular and metabolic disorders on EPC biology will be discussed. The various EPC-based therapies that will be discussed include lipid-lowering agents, antihypertensive agents, antidiabetic drugs, phosphodiesteraze inhibitors, hormones, as well as EPC capturing stents. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Circulating CD34+ progenitor cells and risk of mortality in a population with coronary artery disease.

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Patel, Riyaz S; Li, Qunna; Ghasemzadeh, Nima; Eapen, Danny J; Moss, Lauren D; Janjua, A Umair; Manocha, Pankaj; Kassem, Hatem Al; Veledar, Emir; Samady, Habib; Taylor, W Robert; Zafari, A Maziar; Sperling, Laurence; Vaccarino, Viola; Waller, Edmund K; Quyyumi, Arshed A

2015-01-16

Low circulating progenitor cell numbers and activity may reflect impaired intrinsic regenerative/reparative potential, but it remains uncertain whether this translates into a worse prognosis. To investigate whether low numbers of progenitor cells associate with a greater risk of mortality in a population at high cardiovascular risk. Patients undergoing coronary angiography were recruited into 2 cohorts (1, n=502 and 2, n=403) over separate time periods. Progenitor cells were enumerated by flow cytometry as CD45(med+) blood mononuclear cells expressing CD34, with additional quantification of subsets coexpressing CD133, vascular endothelial growth factor receptor 2, and chemokine (C-X-C motif) receptor 4. Coefficient of variation for CD34 cells was 2.9% and 4.8%, 21.6% and 6.5% for the respective subsets. Each cohort was followed for a mean of 2.7 and 1.2 years, respectively, for the primary end point of all-cause death. There was an inverse association between CD34(+) and CD34(+)/CD133(+) cell counts and risk of death in cohort 1 (β=-0.92, P=0.043 and β=-1.64, P=0.019, respectively) that was confirmed in cohort 2 (β=-1.25, P=0.020 and β=-1.81, P=0.015, respectively). Covariate-adjusted hazard ratios in the pooled cohort (n=905) were 3.54 (1.67-7.50) and 2.46 (1.18-5.13), respectively. CD34(+)/CD133(+) cell counts improved risk prediction metrics beyond standard risk factors. Reduced circulating progenitor cell counts, identified primarily as CD34(+) mononuclear cells or its subset expressing CD133, are associated with risk of death in individuals with coronary artery disease, suggesting that impaired endogenous regenerative capacity is associated with increased mortality. These findings have implications for biological understanding, risk prediction, and cell selection for cell-based therapies. © 2014 American Heart Association, Inc.

Endothelial progenitor cell dysfunction in patients with progressive chronic kidney disease

NARCIS (Netherlands)

Krenning, Guido; Dankers, Patricia Y. W.; Drouven, Johannes W.; Waanders, Femke; Franssen, Casper F. M.; van Luyn, Marja J. A.; Harmsen, Martin C.; Popa, Eliane R.

Krenning G, Dankers PY, Drouven JW, Waanders F, Franssen CF, van Luyn MJ, Harmsen MC, Popa ER. Endothelial progenitor cell dysfunction in patients with progressive chronic kidney disease. Am J Physiol Renal Physiol 296: F1314-F1322, 2009. First published April 1, 2009; doi:

Sun Ginseng Protects Endothelial Progenitor Cells From Senescence Associated Apoptosis

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Im, Wooseok; Chung, Jin-Young; Bhan, Jaejun; Lim, Jiyeon; Lee, Soon-Tae; Chu, Kon; Kim, Manho

2012-01-01

Endothelial progenitor cells (EPC) are a population of cells that circulate in the blood stream. They play a role in angiogenesis and, therefore, can be prognostic markers of vascular repair. Ginsenoside Rg3 prevents endothelial cell apoptosis through the inhibition of the mitochondrial caspase pathway. It also affects estrogen activity, which reduces EPC senescence. Sun ginseng (SG), which is heat-processed ginseng, has a high content of ginsenosides. The purpose of this study was to investigate the protective effects of SG on senescence-associated apoptosis in EPCs. In order to isolate EPCs, mononuclear cells of human blood buffy coats were cultured and characterized by their uptake of acetylated low-density lipoprotein (acLDL) and their binding of Ulex europaeus agglutinin I (ulex-lectin). Flow cytometry with annexin-V staining was performed in order to assess early and late apoptosis. Senescence was determined by β-galactosidase (β-gal) staining. Staining with 4′-6-Diamidino-2-phenylindole verified that most adherent cells (93±2.7%) were acLDL-positive and ulex-lectin-positive. The percentage of β-gal-positive EPCs was decreased from 93.8±2.0% to 62.5±3.6% by SG treatment. A fluorescence-activated cell sorter (FACS) analysis showed that 4.9% of EPCs were late apoptotic in controls. Sun ginseng decreased the apoptotic cell population by 39% in the late stage of apoptosis from control baseline levels. In conclusion, these results show antisenescent and antiapoptotic effects of SG in human-derived EPCs, indicating that SG can enhance EPC-mediated repair mechanisms. PMID:23717107

Obstructive sleep apnea and endothelial progenitor cells

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Wang Q

2013-10-01

Full Text Available Qing Wang,1,* Qi Wu,2,* Jing Feng,3,4 Xin Sun5 1The Second Respiratory Department of the First People's Hospital of Kunming, Yunnan, People's Republic of China; 2Tianjin Haihe Hospital, Tianjin, People's Republic of China; 3Respiratory Department of Tianjin Medical University General Hospital, Tianjin, People's Republic of China; 4Division of Pulmonary and Critical Care Medicine, Duke University Medical Center, Durham, NC, USA; 5Respiratory Department of Tianjin Haihe Hospital, Tianjin, People's Republic of China *These authors contributed equally to this work Background: Obstructive sleep apnea (OSA occurs in 4% of middle-aged men and 2% of middle-aged women in the general population, and the prevalence is even higher in specific patient groups. OSA is an independent risk factor for a variety of cardiovascular diseases. Endothelial injury could be the pivotal determinant in the development of cardiovascular pathology in OSA. Endothelial damage ultimately represents a dynamic balance between the magnitude of injury and the capacity for repair. Bone marrow–derived endothelial progenitor cells (EPCs within adult peripheral blood present a possible means of vascular maintenance that could home to sites of injury and restore endothelial integrity and normal function. Methods: We summarized pathogenetic mechanisms of OSA and searched for available studies on numbers and functions of EPCs in patients with OSA to explore the potential links between the numbers and functions of EPCs and OSA. In particular, we tried to elucidate the molecular mechanisms of the effects of OSA on EPCs. Conclusion: Intermittent hypoxia cycles and sleep fragmentation are major pathophysiologic characters of OSA. Intermittent hypoxia acts as a trigger of oxidative stress, systemic inflammation, and sympathetic activation. Sleep fragmentation is associated with a burst of sympathetic activation and systemic inflammation. In most studies, a reduction in circulating EPCs has

Capture of circulatory endothelial progenitor cells and accelerated re-endothelialization of a bio-engineered stent in human ex vivo shunt and rabbit denudation model

NARCIS (Netherlands)

K. Larsen (Katarína); C. Cheng (Caroline (Ka Lai)); D. Tempel (Dennie); S. Parker (Sherry); S. Yazdani (Saami); W.K. den Dekker (Wijnand); H.J. Houtgraaf (Jaco); R. de Jong (Renate); S. Swager-ten Hoor (Stijn); E. Ligtenberg (Erik); S.R. Hanson (Stephen); R. Rowland (Steve); F. Kolodgie (Frank); P.W.J.C. Serruys (Patrick); R. Virmani (Renu); H.J. Duckers (Henricus)

2012-01-01

textabstractThe Genous™ Bio-engineered R™ stent (GS) aims to promote vascular healing by capture of circulatory endothelial progenitor cells (EPCs) to the surface of the stent struts, resulting in accelerated re-endothelialization. Here, we assessed the function of the GS in comparison to bare-metal

Haploinsufficiency of the insulin-like growth factor-1 receptor enhances endothelial repair and favorably modifies angiogenic progenitor cell phenotype.

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Yuldasheva, Nadira Y; Rashid, Sheikh Tawqeer; Haywood, Natalie J; Cordell, Paul; Mughal, Romana; Viswambharan, Hema; Imrie, Helen; Sukumar, Piruthivi; Cubbon, Richard M; Aziz, Amir; Gage, Matthew; Mbonye, Kamatamu Amanda; Smith, Jessica; Galloway, Stacey; Skromna, Anna; Scott, D Julian A; Kearney, Mark T; Wheatcroft, Stephen B

2014-09-01

Defective endothelial regeneration predisposes to adverse arterial remodeling and is thought to contribute to cardiovascular disease in type 2 diabetes mellitus. We recently demonstrated that the type 1 insulin-like growth factor receptor (IGF1R) is a negative regulator of insulin sensitivity and nitric oxide bioavailability. In this report, we examined partial deletion of the IGF1R as a potential strategy to enhance endothelial repair. We assessed endothelial regeneration after wire injury in mice and abundance and function of angiogenic progenitor cells in mice with haploinsufficiency of the IGF1R (IGF1R(+/-)). Endothelial regeneration after arterial injury was accelerated in IGF1R(+/-) mice. Although the yield of angiogenic progenitor cells was lower in IGF1R(+/-) mice, these angiogenic progenitor cells displayed enhanced adhesion, increased secretion of insulin-like growth factor-1, and enhanced angiogenic capacity. To examine the relevance of IGF1R manipulation to cell-based therapy, we transfused IGF1R(+/-) bone marrow-derived CD117(+) cells into wild-type mice. IGF1R(+/-) cells accelerated endothelial regeneration after arterial injury compared with wild-type cells and did not alter atherosclerotic lesion formation. Haploinsufficiency of the IGF1R is associated with accelerated endothelial regeneration in vivo and enhanced tube forming and adhesive potential of angiogenic progenitor cells in vitro. Partial deletion of IGF1R in transfused bone marrow-derived CD117(+) cells enhanced their capacity to promote endothelial regeneration without altering atherosclerosis. Our data suggest that manipulation of the IGF1R could be exploited as novel therapeutic approach to enhance repair of the arterial wall after injury. © 2014 American Heart Association, Inc.

Circulating endothelial cells in patients with venous thromboembolism and myeloproliferative neoplasms.

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Cláudia Torres

Full Text Available BACKGROUND: Circulating endothelial cells (CEC may be a biomarker of vascular injury and pro-thrombotic tendency, while circulating endothelial progenitor cells (CEP may be an indicator for angiogenesis and vascular remodelling. However, there is not a universally accepted standardized protocol to identify and quantify these cells and its clinical relevancy remains to be established. OBJECTIVES: To quantify CEC and CEP in patients with venous thromboembolism (VTE and with myeloproliferative neoplasms (MPN, to characterize the CEC for the expression of activation (CD54, CD62E and procoagulant (CD142 markers and to investigate whether they correlate with other clinical and laboratory data. PATIENTS AND METHODS: Sixteen patients with VTE, 17 patients with MPN and 20 healthy individuals were studied. The CEC and CEP were quantified and characterized in the blood using flow cytometry, and the demographic, clinical and laboratory data were obtained from hospital records. RESULTS: We found the CEC counts were higher in both patient groups as compared to controls, whereas increased numbers of CEP were found only in patients with MPN. In addition, all disease groups had higher numbers of CD62E+ CEC as compared to controls, whereas only patients with VTE had increased numbers of CD142+ and CD54+ CEC. Moreover, the numbers of total and CD62+ CEC correlated positively with the white blood cells (WBC counts in both groups of patients, while the numbers of CEP correlated positively with the WBC counts only in patients with MPN. In addition, in patients with VTE a positive correlation was found between the numbers of CD54+ CEC and the antithrombin levels, as well as between the CD142+ CEC counts and the number of thrombotic events. CONCLUSIONS: Our study suggests that CEC counts may reveal endothelial injury in patients with VTE and MPN and that CEC may express different activation-related phenotypes depending on the disease status.

Mesenchymal stromal cell derived endothelial progenitor treatment in patients with refractory angina

DEFF Research Database (Denmark)

Friis, Tina; Haack-Sørensen, Mandana; Mathiasen, Anders B

2011-01-01

Abstract Aims. We evaluated the feasibility, safety and efficacy of intra-myocardial injection of autologous mesenchymal stromal cells derived endothelial progenitor cell (MSC) in patients with stable coronary artery disease (CAD) and refractory angina in this first in man trial. Methods and resu......Abstract Aims. We evaluated the feasibility, safety and efficacy of intra-myocardial injection of autologous mesenchymal stromal cells derived endothelial progenitor cell (MSC) in patients with stable coronary artery disease (CAD) and refractory angina in this first in man trial. Methods...... and results. A total of 31 patients with stable CAD, moderate to severe angina and no further revascularization options, were included. Bone marrow MSC were isolated and culture expanded for 6-8 weeks. It was feasible and safe to establish in-hospital culture expansion of autologous MSC and perform intra......-myocardial injection of MSC. After six months follow-up myocardial perfusion was unaltered, but the patients increased exercise capacity (p angina attacks (p Angina Questionnaire (SAQ) evaluations (p

The chemotactic activity of beta-carotene in endothelial cell progenitors and human umbilical vein endothelial cells: A microarray analysis

NARCIS (Netherlands)

Polus, A.; Kiec-wilk, B.; Hartwich, J.; Balwierz, A.; Stachura, J.; Dyduch, G.; Laidler, P.; Zagajewski, J.; Langman, T.; Schmitz, G.; Goralcsky, R.; Wertz, K.; Riss, G.; Keijer, J.; Dembinska-Kiec, A.

2006-01-01

Objectives: Endothelial cells and their progenitors play an important role in angiogenesis that is essential for organogenesis and tissue remodelling, as well as for inflammatory responses and carcinogenesis in all periods of life. In the present study, the authors concentrated on the direct effect

Physalis minima Leaves Extract Induces Re-Endothelialization in Deoxycorticosterone Acetate-Salt-Induced Endothelial Dysfunction in Rats

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Dian Nugrahenny

2018-02-01

Full Text Available The administration of deoxy-corticosterone acetate (DOCA-salt can induce oxidative stress leading to decrease the bioavailability of nitric oxide (NO, increase senescence of circulating endothelial progenitor cells (EPCs, thus contributing to endothelial dysfunction. This study was aimed to investigate the effects of Physalis minima L. leaves extract on serum NO levels, circulating EPCs number, and histopathology of tail artery endothelial cells in DOCA-salt-induced endothelial dysfunction in rats. Twenty-five male Wistar rats were randomly divided into five groups: rats without any treatment (normal, rats treated with DOCA (10 mg/kgBW s.c. twice weekly and given 0.9% NaCl to drink ad libitum for 6 weeks, and DOCA-salt-induced rats orally supplemented with P. minima leaves extract at doses of 500, 1500, or 2500 mg/kgBW for 4 weeks. Serum NO levels were measured by colorimetry. The number of circulating EPCs (CD34+/CD133+ cells was determined by flow cytometry. The tail artery sections were histologically processed with hematoxylin-eosin staining. DOCA-salt-induced rats showed significantly (p<0.05 decrease in serum NO levels and circulating EPCs number compared to the normal. There was also more detached tail artery endothelial cells in DOCA-salt-induced rats. P. minima leaves extract at a dose of 500 mg/kgBW significantly (p<0.05 increased serum NO level and circulating EPCs number, and also induced an optimal re-endothelialization in DOCA-salt-induced rats. P. minima leave extract dose-dependently increases NO bioavailability contributing to enhanced EPCs mobilization, thereby promoting re-endothelialization in DOCA-salt-induced endothelial dysfunction in rats.

Functional evaluation of circulating hematopoietic progenitors in Noonan syndrome

Science.gov (United States)

TIMEUS, FABIO; CRESCENZIO, NICOLETTA; BALDASSARRE, GIUSEPPINA; DORIA, ALESSANDRA; VALLERO, STEFANO; FOGLIA, LUISELDA; PAGLIANO, SARA; ROSSI, CESARE; SILENGO, MARGHERITA CIRILLO; RAMENGHI, UGO; FAGIOLI, FRANCA; DI MONTEZEMOLO, LUCA CORDERO; FERRERO, GIOVANNI BATTISTA

2013-01-01

Noonan syndrome (NS) is an autosomal dominant disorder, characterized by short stature, multiple dysmorphisms and congenital heart defects. A myeloproliferative disorder (NS/MPD), resembling juvenile myelomonocytic leukemia (JMML), is occasionally diagnosed in infants with NS. In the present study, we performed a functional evaluation of the circulating hematopoietic progenitors in a series of NS, NS/MPD and JMML patients. The different functional patterns were compared with the aim to identify a possible NS subgroup worthy of stringent hematological follow-up for an increased risk of MPD development. We studied 27 NS and 5 JMML patients fulfilling EWOG-MDS criteria. The more frequent molecular defects observed in NS were mutations in the PTPN11 and SOS genes. The absolute count of monocytes, circulating CD34+ hematopoietic progenitors, their apoptotic rate and the number of circulating CFU-GMs cultured in the presence of decreasing concentrations or in the absence of granulocyte-macrophage colony-stimulating factor (GM-CSF) were evaluated. All JMML patients showed monocytosis >1,000/μl. Ten out of the 27 NS patients showed monocytosis >1,000/μl, which included the 3 NS/MPD patients. In JMML patients, circulating CD34+ cells were significantly increased (median, 109.8/μl; range, 44–232) with a low rate of apoptosis (median, 2.1%; range, 0.4–12.1%), and circulating CFU-GMs were hyper-responsive to GM-CSF. NS/MPD patients showed the same flow cytometric pattern as the JMML patients (median, CD34+ cells/μl, 205.7; range, 58–1374; median apoptotic rate, 1.4%; range, 0.2–2.4%) and their circulating CFU-GMs were hyper-responsive to GM-CSF. These functional alterations appeared 10 months before the typical clinical manifestations in 1 NS/MPD patient. In NS, the CD34+ absolute cell count and circulating CFU-GMs showed a normal pattern (median CD34+ cells/μl, 4.9; range, 1.3–17.5), whereas the CD34+ cell apoptotic rate was significantly decreased in

Pinocembrin ex vivo preconditioning improves the therapeutic efficacy of endothelial progenitor cells in monocrotaline-induced pulmonary hypertension in rats.

Science.gov (United States)

Ahmed, Lamiaa A; Rizk, Sherine M; El-Maraghy, Shohda A

2017-08-15

Pulmonary hypertension is still not curable and the available current therapies can only alleviate symptoms without hindering the progression of disease. The present study was directed to investigate the possible modulatory effect of pinocembrin on endothelial progenitor cells transplanted in monocrotaline-induced pulmonary hypertension in rats. Pulmonary hypertension was induced by a single subcutaneous injection of monocrotaline (60mg/kg). Endothelial progenitor cells were in vitro preconditioned with pinocembrin (25mg/L) for 30min before being i.v. injected into rats 2weeks after monocrotaline administration. Four weeks after monocrotaline administration, blood pressure, electrocardiography and right ventricular systolic pressure were recorded. Rats were sacrificed and serum was separated for determination of endothelin-1 and asymmetric dimethylarginine levels. Right ventricles and lungs were isolated for estimation of tumor necrosis factor-alpha and transforming growth factor-beta contents as well as caspase-3 activity. Moreover, protein expression of matrix metalloproteinase-9 and endothelial nitric oxide synthase in addition to myocardial connexin-43 was assessed. Finally, histological analysis of pulmonary arteries, cardiomyocyte cross-sectional area and right ventricular hypertrophy was performed and cryosections were done for estimation of cell homing. Preconditioning with pinocembrin provided a significant improvement in endothelial progenitor cells' effect towards reducing monocrotaline-induced elevation of inflammatory, fibrogenic and apoptotic markers. Furthermore, preconditioned cells induced a significant amelioration of endothelial markers and cell homing and prevented monocrotaline-induced changes in right ventricular function and histological analysis compared with native cells alone. In conclusion, pinocembrin significantly improves the therapeutic efficacy of endothelial progenitor cells in monocrotaline-induced pulmonary hypertension in rats

Circulating endothelial cells are increased in chronic myeloid leukemia blast crisis

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C.R.T. Godoy

2015-06-01

Full Text Available We measured circulating endothelial precursor cells (EPCs, activated circulating endothelial cells (aCECs, and mature circulating endothelial cells (mCECs using four-color multiparametric flow cytometry in the peripheral blood of 84 chronic myeloid leukemia (CML patients and 65 healthy controls; and vascular endothelial growth factor (VEGF by quantitative real-time PCR in 50 CML patients and 32 healthy controls. Because of an increase in mCECs, the median percentage of CECs in CML blast crisis (0.0146% was significantly higher than in healthy subjects (0.0059%, P0.05. In addition, VEGF gene expression was significantly higher in all phases of CML: 0.245 in blast crisis, 0.320 in the active phase, and 0.330 in chronic phase patients than it was in healthy subjects (0.145. In conclusion, CML in blast crisis had increased levels of CECs and VEGF gene expression, which may serve as markers of disease progression and may become targets for the management of CML.

Estradiol-induced, endothelial progenitor cell-mediated neovascularization in male mice with hind-limb ischemia

NARCIS (Netherlands)

Ruifrok, Willem-Peter T.; de Boer, Rudolf A.; Iwakura, Atsushi; Silver, Marcy; Kusano, Kengo; Tio, Rene A.; Losordo, Douglas W.

We investigated whether administration of estradiol to male mice augments mobilization of bone marrow-derived endothelial progenitor cells (EPC) and incorporation into foci of neovascularization after hind-limb ischemia, thereby contributing to blood flow restoration. Mice were randomized and

Macrophage-Mediated Lymphangiogenesis: The Emerging Role of Macrophages as Lymphatic Endothelial Progenitors

International Nuclear Information System (INIS)

Ran, Sophia; Montgomery, Kyle E.

2012-01-01

It is widely accepted that macrophages and other inflammatory cells support tumor progression and metastasis. During early stages of neoplastic development, tumor-infiltrating macrophages (TAMs) mount an immune response against transformed cells. Frequently, however, cancer cells escape the immune surveillance, an event that is accompanied by macrophage transition from an anti-tumor to a pro-tumorigenic type. The latter is characterized by high expression of factors that activate endothelial cells, suppress immune response, degrade extracellular matrix, and promote tumor growth. Cumulatively, these products of TAMs promote tumor expansion and growth of both blood and lymphatic vessels that facilitate metastatic spread. Breast cancers and other epithelial malignancies induce the formation of new lymphatic vessels (i.e., lymphangiogenesis) that leads to lymphatic and subsequently, to distant metastasis. Both experimental and clinical studies have shown that TAMs significantly promote tumor lymphangiogenesis through paracrine and cell autonomous modes. The paracrine effect consists of the expression of a variety of pro-lymphangiogenic factors that activate the preexisting lymphatic vessels. The evidence for cell-autonomous contribution is based on the observed tumor mobilization of macrophage-derived lymphatic endothelial cell progenitors (M-LECP) that integrate into lymphatic vessels prior to sprouting. This review will summarize the current knowledge of macrophage-dependent growth of new lymphatic vessels with specific emphasis on an emerging role of macrophages as lymphatic endothelial cell progenitors (M-LECP)

The Use of Endothelial Progenitor Cells for the Regeneration of Musculoskeletal and Neural Tissues

OpenAIRE

Kamei, Naosuke; Atesok, Kivanc; Ochi, Mitsuo

2017-01-01

Endothelial progenitor cells (EPCs) derived from bone marrow and blood can differentiate into endothelial cells and promote neovascularization. In addition, EPCs are a promising cell source for the repair of various types of vascularized tissues and have been used in animal experiments and clinical trials for tissue repair. In this review, we focused on the kinetics of endogenous EPCs during tissue repair and the application of EPCs or stem cell populations containing EPCs for tissue regenera...

Circulating endothelial cells and procoagulant microparticles in patients with glioblastoma: prognostic value.

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Gaspar Reynés

Full Text Available AIM: Circulating endothelial cells and microparticles are prognostic factors in cancer. However, their prognostic and predictive value in patients with glioblastoma is unclear. The objective of this study was to investigate the potential prognostic value of circulating endothelial cells and microparticles in patients with newly diagnosed glioblastoma treated with standard radiotherapy and concomitant temozolomide. In addition, we have analyzed the methylation status of the MGMT promoter. METHODS: Peripheral blood samples were obtained before and at the end of the concomitant treatment. Blood samples from healthy volunteers were also obtained as controls. Endothelial cells were measured by an immunomagnetic technique and immunofluorescence microscopy. Microparticles were quantified by flow cytometry. Microparticle-mediated procoagulant activity was measured by endogen thrombin generation and by phospholipid-dependent clotting time. Methylation status of MGMT promoter was determined by multiplex ligation-dependent probe amplification. RESULTS: Pretreatment levels of circulating endothelial cells and microparticles were higher in patients than in controls (p<0.001. After treatment, levels of microparticles and thrombin generation decreased, and phospholipid-dependent clotting time increased significantly. A high pretreatment endothelial cell count, corresponding to the 99(th percentile in controls, was associated with poor overall survival. MGMT promoter methylation was present in 27% of tumor samples and was associated to a higher overall survival (66 weeks vs 30 weeks, p<0.004. CONCLUSION: Levels of circulating endothelial cells may have prognostic value in patients with glioblastoma.

Macrophages commit postnatal endothelium-derived progenitors to angiogenesis and restrict endothelial to mesenchymal transition during muscle regeneration.

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Zordan, P; Rigamonti, E; Freudenberg, K; Conti, V; Azzoni, E; Rovere-Querini, P; Brunelli, S

2014-01-30

The damage of the skeletal muscle prompts a complex and coordinated response that involves the interactions of many different cell populations and promotes inflammation, vascular remodeling and finally muscle regeneration. Muscle disorders exist in which the irreversible loss of tissue integrity and function is linked to defective neo-angiogenesis with persistence of tissue necrosis and inflammation. Here we show that macrophages (MPs) are necessary for efficient vascular remodeling in the injured muscle. In particular, MPs sustain the differentiation of endothelial-derived progenitors to contribute to neo-capillary formation, by secreting pro-angiogenic growth factors. When phagocyte infiltration is compromised endothelial-derived progenitors undergo a significant endothelial to mesenchymal transition (EndoMT), possibly triggered by the activation of transforming growth factor-β/bone morphogenetic protein signaling, collagen accumulates and the muscle is replaced by fibrotic tissue. Our findings provide new insights in EndoMT in the adult skeletal muscle, and suggest that endothelial cells in the skeletal muscle may represent a new target for therapeutic intervention in fibrotic diseases.

Hydrogel-embedded endothelial progenitor cells evade LPS and mitigate endotoxemia.

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Ghaly, Tammer; Rabadi, May M; Weber, Mia; Rabadi, Seham M; Bank, Michael; Grom, John M; Fallon, John T; Goligorsky, Michael S; Ratliff, Brian B

2011-10-01

Sepsis and its complications are associated with poor clinical outcomes. The circulatory system is a well-known target of lipopolysaccharide (LPS). Recently, several clinical studies documented mobilization of endothelial progenitor cells (EPCs) during endotoxemia, with the probability of patients' survival correlating with the rise in circulating EPCs. This fact combined with endotoxemia-induced vascular injury led us to hypothesize that the developing functional EPC incompetence could impede vascular repair and that adoptive transfer of EPCs could improve hemodynamics in endotoxemia. We used LPS injection to model endotoxemia. EPCs isolated from endotoxemic mice exhibited impaired clonogenic potential and LPS exerted Toll-like receptor 4-mediated cytotoxic effects toward EPCs, which was mitigated by embedding them in hyaluronic acid (HA) hydrogels. Therefore, intact EPCs were either delivered intravenously or embedded within pronectin-coated HA hydrogels. Adoptive transfer of EPCs in LPS-injected mice improved control of blood pressure and reduced hepatocellular and renal dysfunction. Specifically, EPC treatment was associated with the restoration of renal microcirculation and improved renal function. EPC therapy was most efficient when cells were delivered embedded in HA hydrogel. These findings establish major therapeutic benefits of adoptive transfer of EPCs, especially when embedded in HA hydrogels, in mice with LPS-induced endotoxemia, and they argue that hemodynamic and renal abnormalities of endotoxemia are in significant part due to developing incompetence of endogenous EPCs.

Fabrication of endothelial progenitor cell capture surface via DNA aptamer modifying dopamine/polyethyleneimine copolymer film

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Li, Xin; Deng, Jinchuan; Yuan, Shuheng; Wang, Juan; Luo, Rifang; Chen, Si [Key Lab. of Advanced Technology for Materials of Education Ministry, Southwest Jiaotong University, Chengdu 610031 (China); School of Material Science and Engineering, Southwest Jiaotong University, Chengdu 610031 (China); Wang, Jin, E-mail: jinxxwang@263.net [Key Lab. of Advanced Technology for Materials of Education Ministry, Southwest Jiaotong University, Chengdu 610031 (China); Huang, Nan [Key Lab. of Advanced Technology for Materials of Education Ministry, Southwest Jiaotong University, Chengdu 610031 (China); School of Material Science and Engineering, Southwest Jiaotong University, Chengdu 610031 (China)

2016-11-15

Highlights: • The dopamine/PEI film with controlled amine density was successfully prepared. • The DNA aptamer was assembled onto the film via electrostatic incorporation. • The A@DPfilmscanspecificallyandeffectivelycaptureEPCs. • The A@DP film can support the survival of ECs, control the hyperplasia of SMCs. • The dynamic/co-culture models are useful for studying cells competitive adhesion. - Abstract: Endothelial progenitor cells (EPCs) are mainly located in bone marrow and circulate, and play a crucial role in repairmen of injury endothelium. One of the most promising strategies of stents designs were considered to make in-situ endothelialization in vivo via EPC-capture biomolecules on a vascular graft to capture EPCs directly from circulatory blood. In this work, an EPC specific aptamer with a 34 bases single strand DNA sequence was conjugated onto the stent surface via dopamine/polyethyleneimine copolymer film as a platform and linker. The assembled density of DNA aptamer could be regulated by controlling dopamine percentage in this copolymer film. X-ray photoelectron spectroscopy (XPS), water contact angle (WCA) and fluorescence test confirmed the successful immobilization of DNA aptamer. To confirm its biofunctionality and cytocompatibility, the capturing cells ability of the aptamer modified surface and the effects on the growth behavior of human umbilical vein endothelial cells (HUVECs), smooth muscle cells (SMCs) were investigated. The aptamer functionalized sample revealed a good EPC-capture ability, and had a cellular friendly feature for both EPC and EC growth, while not stimulated the hyperplasia of SMCs. And, the co-culture experiment of three types of cells confirmed the specificity capturing of EPCs to aptamer modified surface, rather than ECs and SMCs. These data suggested that this aptamer functionalized surface may have a large potentiality for the application of vascular grafts with targeted endothelialization.

Fabrication of endothelial progenitor cell capture surface via DNA aptamer modifying dopamine/polyethyleneimine copolymer film

International Nuclear Information System (INIS)

Li, Xin; Deng, Jinchuan; Yuan, Shuheng; Wang, Juan; Luo, Rifang; Chen, Si; Wang, Jin; Huang, Nan

2016-01-01

Highlights: • The dopamine/PEI film with controlled amine density was successfully prepared. • The DNA aptamer was assembled onto the film via electrostatic incorporation. • The A@DPfilmscanspecificallyandeffectivelycaptureEPCs. • The A@DP film can support the survival of ECs, control the hyperplasia of SMCs. • The dynamic/co-culture models are useful for studying cells competitive adhesion. - Abstract: Endothelial progenitor cells (EPCs) are mainly located in bone marrow and circulate, and play a crucial role in repairmen of injury endothelium. One of the most promising strategies of stents designs were considered to make in-situ endothelialization in vivo via EPC-capture biomolecules on a vascular graft to capture EPCs directly from circulatory blood. In this work, an EPC specific aptamer with a 34 bases single strand DNA sequence was conjugated onto the stent surface via dopamine/polyethyleneimine copolymer film as a platform and linker. The assembled density of DNA aptamer could be regulated by controlling dopamine percentage in this copolymer film. X-ray photoelectron spectroscopy (XPS), water contact angle (WCA) and fluorescence test confirmed the successful immobilization of DNA aptamer. To confirm its biofunctionality and cytocompatibility, the capturing cells ability of the aptamer modified surface and the effects on the growth behavior of human umbilical vein endothelial cells (HUVECs), smooth muscle cells (SMCs) were investigated. The aptamer functionalized sample revealed a good EPC-capture ability, and had a cellular friendly feature for both EPC and EC growth, while not stimulated the hyperplasia of SMCs. And, the co-culture experiment of three types of cells confirmed the specificity capturing of EPCs to aptamer modified surface, rather than ECs and SMCs. These data suggested that this aptamer functionalized surface may have a large potentiality for the application of vascular grafts with targeted endothelialization.

{sup 13}C dynamic nuclear polarization for measuring metabolic flux in endothelial progenitor cells

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Nielsen, Nathalie; Laustsen, Christoffer; Bertelsen, Lotte Bonde, E-mail: Lotte@clin.au.dk

2016-11-15

Endothelial progenitor cells (EPCs) represent a heterogeneous cell population that is believed to be involved in vasculogenesis. With the purpose of enhancing endothelial repair, EPCs could have a potential for future cell therapies. Due to the low amount of EPCs in the peripheral circulating blood, in vitro expansion is needed before administration to recipients and the effects of in vitro culturing is still an under-evaluated field with little knowledge of how the cells change over time in culture. The aim of this study was to use hyperpolarised carbon-13 magnetic resonance spectroscopy to profile important metabolic pathways in a population of progenitor cells and to show that cell culturing in 3D scaffolds seem to block the metabolic processes that leads to cell senescence. The metabolic breakdown of hyperpolarized [1-{sup 13}C]pyruvate was followed after injection of the substrate to a bioreactor system with EPCs either adhered to 3D printed scaffolds or kept in cell suspension. The pyruvate-to-lactate conversion was elevated in suspension of EPCs compared to the EPCs adhered to scaffolds. Furthermore in the setup with EPCs in suspension, an increase in lactate production was seen over time indicating that the older the cultures of EPCs was before using the cells for cell suspension experiments, the more lactate they produce, compared to a constant lactate level in the cells adhered to scaffolds. It could therefore be stated that cells grown first in 2D culture and subsequent prepared for cell suspension show a metabolism with higher lactate production consistent with cells senescence processes compared to cells grown first at 2D culture and subsequent in the 3D printed scaffolds, where metabolism shows no sign of metabolic shifting during the monitored period. - Highlights: • Hyperpolarized 13C MRS detects EPCs metabolic changes associated with ageing and cultivating conditions. • Increased lactate production in EPC’s correlates positively with aging. �

Amlodipine Ameliorates Ischemia-Induced Neovascularization in Diabetic Rats through Endothelial Progenitor Cell Mobilization

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Jiayin Sun

2016-01-01

Full Text Available Objectives. We investigated whether amlodipine could improve angiogenic responses in a diabetic rat model of acute myocardial infarction (AMI through improving bone marrow endothelial progenitor cell (EPC mobilization, in the same way as angiotensin converting enzyme inhibitors. Methods. After induction of AMI by coronary artery ligation, diabetic rats were randomly assigned to receive perindopril (2 mgkg−1 day−1, amlodipine (2.5 mgkg−1 day−1, or vehicle by gavage (n=20 per group. Circulating EPC counts before ligation and on days 1, 3, 5, 7, 14, and 28 after AMI were measured in each group. Microvessel density, cardiac function, and cardiac remodeling were assessed 4 weeks after treatment. The signaling pathway related to EPC mobilization was also measured. Results. Circulating EPC count in amlodipine- and perindopril-treated rats peaked at day 7, to an obvious higher level than the control group peak which was reached earlier (at day 5. Rats treated with amlodipine showed improved postischemia neovascularization and cardiac function, together with reduced cardiac remodeling, decreased interstitial fibrosis, and cardiomyocyte apoptosis. Amlodipine treatment also increased cardiac SDF-1/CXCR4 expression and gave rise to activation of VEGF/Akt/eNOS signaling in bone marrow. Conclusions. Amlodipine promotes neovascularization by improving EPC mobilization from bone marrow in diabetic rats after AMI, and activation of VEGF/Akt/eNOS signaling may in part contribute to this.

Donor-derived circulating endothelial cells after kidney transplantation

NARCIS (Netherlands)

Popa, ER; Kas-Deelen, AM; Hepkema, BG; van Son, WJ; The, TH; Harmsen, MC

2002-01-01

Background. In solid-organ transplantation, the allograft vasculature, in particular the endothelium, is prone to injury inflicted by peritransplantational and posttransplantational factors. Previously, we have shown that circulating endothelial cells (cEC) can be detected in the peripheral blood of

Double-chimera proteins to enhance recruitment of endothelial cells and their progenitor cells.

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Behjati, M; Kazemi, M; Hashemi, M; Zarkesh-Esfahanai, S H; Bahrami, E; Hashemi-Beni, B; Ahmadi, R

2013-08-20

Enhanced attraction of selective vascular reparative cells is of great importance in order to increase vascular patency after endovascular treatments. We aimed to evaluate efficient attachment of endothelial cells and their progenitors on surfaces coated with mixture of specific antibodies, L-selectin and VE-cadherin, with prohibited platelet attachment. The most efficient conditions for coating of L-selectin-Fc chimera and VE-cadherin-Fc chimera proteins were first determined by protein coating on ELISA plates. The whole processes were repeated on titanium substrates, which are commonly used to coat stents. Endothelial progenitor cells (EPCs) and human umbilical vein endothelial cells (HUVECs) were isolated and characterized by flow cytometry. Cell attachment, growth, proliferation, viability and surface cytotoxicity were evaluated using nuclear staining and MTT assay. Platelet and cell attachment were evaluated using scanning electron microscopy. Optimal concentration of each protein for surface coating was 50 ng/ml. The efficacy of protein coating was both heat and pH independent. Calcium ions had significant impact on simultaneous dual-protein coating (P<0.05). Coating stability data revealed more than one year stability for these coated proteins at 4°C. L-selectin and VE-cadherin (ratio of 50:50) coated surface showed highest EPC and HUVEC attachment, viability and proliferation compared to single protein coated and non-coated titanium surfaces (P<0.05). This double coated surface did not show any cytotoxic effect. Surfaces coated with L-selectin and VE-cadherin are friendly surface for EPC and endothelial cell attachment with less platelet attachment. These desirable factors make the L-selectin and VE-cadherin coated surfaces perfect candidate endovascular device. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Association of endothelial progenitor cells and peptic ulcer treatment in patients with type 2 diabetes mellitus.

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Nie, Zhihong; Xu, Limin; Li, Chuanyuan; Tian, Tao; Xie, Pingping; Chen, Xia; Li, Bojing

2016-05-01

The present study aimed to investigate the association between endothelial progenitor cells (EPCs) and peptic ulcers in patients with or without type 2 diabetes mellitus (T2DM), in association with the efficiency of peptic ulcer treatment. The study recruited healthy subjects and peptic ulcer patients with or without T2DM. All the ulcer patients, including those with and without T2DM, were administered omeprazole for 8 weeks. Peptic ulcer patients with T2DM were additionally treated with glipizide and novolin. Blood samples were then obtained from the three groups following ulcer treatment. CD133 + cells were isolated from the blood samples using magnetic bead selection, and cultured in complete medium 199. Morphological and quantity changes in EPCs were observed by light and fluorescence microscopy. In addition, flow cytometric analysis was used to quantify the number of vascular endothelial cells. The treatment was partially effective in 7 of the 32 peptic ulcer patients without T2DM and 12 of the 32 peptic ulcer patients with T2DM. However, this treatment was ineffective in 20 of the 32 peptic ulcer patients with T2DM. Notably, 25 peptic ulcer patients without T2DM were defined as completely recovered following treatment. In addition, the number of circulating EPCs as well as their colony forming ability was significantly reduced (Ppeptic ulcer patients with T2DM following ulcer treatment, compared with the other groups. Circulating EPC counts were significantly increased in peptic ulcer patients without T2DM, as compared with the healthy controls. With regards to colony formation, peptic ulcer patients without T2DM did not exhibit improved colony formation ability. In conclusion, the number of circulating EPCs and their colony-forming ability was significantly reduced in peptic ulcer patients with T2DM following ulcer treatment when compared with the other groups. This suggests that the poor curative effect of peptic ulcer treatment in these patients is

Stromal Cells Act as Guardians for Endothelial Progenitors by Reducing Their Immunogenicity After Co-Transplantation.

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Souidi, Naima; Stolk, Meaghan; Rudeck, Juliane; Strunk, Dirk; Schallmoser, Katharina; Volk, Hans-Dieter; Seifert, Martina

2017-05-01

Regeneration of injured tissues requires effective therapeutic strategies supporting vasculogenesis. The lack of instantly available autologous cell sources and immunogenicity of allogeneic endothelial (progenitor) cells limits clinical progress. Based on the immunosuppressive potency of mesenchymal stem/progenitor cells (MSCs), we investigated whether crosstalk between endothelial colony-forming progenitor cells (ECFCs) and MSCs during vasculogenesis could lower allogeneic T cell responses against ECFCs allowing long-term engraftment in vivo. Immunodeficient mice received subcutaneous grafts containing human ECFCs alone, or pairs of human ECFCs/MSCs from the same umbilical cord (UC) to study vasculogenesis in the presence of human leukocyte antigen (HLA)-mismatched human peripheral blood mononuclear cells (PBMCs). In vitro, cell surface marker changes due to interferon gamma (IFNγ) stimulation during ECFC/MSC coculture were determined and further effects on allostimulated T cell proliferation and cytotoxic lysis were measured. IFNγ-induced HLA-DR expression on ECFCs and MSCs, but both cell types had significantly less HLA-DR in cocultures. ECFC-induced T cell proliferation was abolished after MSC coculture as a result of HLA-DR downregulation and indolamin-2,3-dioxygenase activation. Additionally, allospecific CD8 + T cell-mediated lysis of ECFCs was reduced in cocultures. ECFC/MSC coapplication in immunodeficient mice not only promoted the generation of improved blood vessel architecture after 6 weeks, but also reduced intragraft immune cell infiltration and endothelial HLA-DR expression following PBMC reconstitution. Crosstalk between UC-derived ECFCs and MSCs after combined transplantation can lower the risk of ECFC rejection, thus enabling their coapplication for therapeutic vasculogenesis. Stem Cells 2017;35:1233-1245. © 2017 AlphaMed Press.

Effect of ambient temperature on the proliferation of brown adipocyte progenitors and endothelial cells during postnatal BAT development in Syrian hamsters.

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Nagaya, Kazuki; Okamatsu-Ogura, Yuko; Nio-Kobayashi, Junko; Nakagiri, Shohei; Tsubota, Ayumi; Kimura, Kazuhiro

2018-04-02

In Syrian hamsters, brown adipose tissue (BAT) develops postnatally through the proliferation and differentiation of brown adipocyte progenitors. In the study reported here, we investigated how ambient temperature influenced BAT formation in neonatal hamsters. In both hamsters raised at 23 or 30 °C, the interscapular fat changed from white to brown coloration in an age-dependent manner and acquired the typical morphological features of BAT by day 16. However, the expression of uncoupling protein 1, a brown adipocyte marker, and of vascular endothelial growth factor α were lower in the group raised at 30 °C than in that raised at 23 °C. Immunofluorescent staining revealed that the proportion of Ki67-expressing progenitors and endothelial cells was lower in the 30 °C group than in the 23 °C group. These results indicate that warm ambient temperature suppresses the proliferation of brown adipocyte progenitors and endothelial cells and negatively affects the postnatal development of BAT in Syrian hamsters.

Extraembryonic origin of circulating endothelial cells.

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Luc Pardanaud

Full Text Available Circulating endothelial cells (CEC are contained in the bone marrow and peripheral blood of adult humans and participate to the revascularization of ischemic tissues. These cells represent attractive targets for cell or gene therapy aimed at improving ischemic revascularization or inhibition of tumor angiogenesis. The embryonic origin of CEC has not been addressed previously. Here we use quail-chick chimeras to study CEC origin and participation to the developing vasculature. CEC are traced with different markers, in particular the QH1 antibody recognizing only quail endothelial cells. Using yolk-sac chimeras, where quail embryos are grafted onto chick yolk sacs and vice-versa, we show that CEC are generated in the yolk sac. These cells are mobilized during wound healing, demonstrating their participation to angiogenic repair processes. Furthermore, we found that the allantois is also able to give rise to CEC in situ. In contrast to the yolk sac and allantois, the embryo proper does not produce CEC. Our results show that CEC exclusively originate from extra-embryonic territories made with splanchnopleural mesoderm and endoderm, while definitive hematopoietic stem cells and endothelial cells are of intra-embryonic origin.

Extraembryonic origin of circulating endothelial cells.

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Pardanaud, Luc; Eichmann, Anne

2011-01-01

Circulating endothelial cells (CEC) are contained in the bone marrow and peripheral blood of adult humans and participate to the revascularization of ischemic tissues. These cells represent attractive targets for cell or gene therapy aimed at improving ischemic revascularization or inhibition of tumor angiogenesis. The embryonic origin of CEC has not been addressed previously. Here we use quail-chick chimeras to study CEC origin and participation to the developing vasculature. CEC are traced with different markers, in particular the QH1 antibody recognizing only quail endothelial cells. Using yolk-sac chimeras, where quail embryos are grafted onto chick yolk sacs and vice-versa, we show that CEC are generated in the yolk sac. These cells are mobilized during wound healing, demonstrating their participation to angiogenic repair processes. Furthermore, we found that the allantois is also able to give rise to CEC in situ. In contrast to the yolk sac and allantois, the embryo proper does not produce CEC. Our results show that CEC exclusively originate from extra-embryonic territories made with splanchnopleural mesoderm and endoderm, while definitive hematopoietic stem cells and endothelial cells are of intra-embryonic origin.

Endothelial-regenerating cells: an expanding universe.

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Steinmetz, Martin; Nickenig, Georg; Werner, Nikos

2010-03-01

Atherosclerosis is the most common cause for cardiovascular diseases and is based on endothelial dysfunction. A growing body of evidence suggests the contribution of bone marrow-derived endothelial progenitor cells, monocytic cells, and mature endothelial cells to vessel formation and endothelial rejuvenation. To this day, various subsets of these endothelial-regenerating cells have been identified according to cellular origin, phenotype, and properties in vivo and in vitro. However, the definition and biology, especially of endothelial progenitor cells, is complex and under heavy debate. In this review, we focus on current definitions of endothelial progenitor cells, highlight the clinical relevance of endothelial-regenerating cells, and provide new insights into cell-cell interactions involved in endothelial cell rejuvenation.

Enhanced adhesion of early endothelial progenitor cells to radiation-induced senescence-like vascular endothelial cells in vitro

International Nuclear Information System (INIS)

Sermsathanasawadi, N.; Inoue, Yoshinori; Iwai, Takehisa; Ishii, Hideto; Yoshida, Masayuki; Igarashi, Kaori; Miura, Masahiko

2009-01-01

The effects of ionizing radiation (IR) on tumor neovascularization are still unclear. We previously reported that vascular endothelial cells (ECs) expressing the IR-induced senescence-like (IRSL) phenotype exhibit a significant decrease in angiogenic activity in vitro. In this study, we examined the effects of the IRSL phenotype on adhesion to early endothelial progenitor cells (early EPCs). Adhesion of human peripheral blood-derived early EPCs to human umbilical vein endothelial cells (HUVECs) expressing the IRSL phenotype was evaluated by an adhesion assay under static conditions. It was revealed that the IRSL HUVECs supported significantly more adhesion of early EPCs than normal HUVECs. Expressions of ICAM-1, VCAM-1 and E-selectin were up-regulated in IRSL HUVECs. Pre-treatment of IRSL HUVECs with adhesion-blocking monoclonal antibodies against E-selectin and VCAM-1 significantly reduced early EPC adhesion to IRSL HUVECs, suggesting a potential role for the E-selectin and VCAM-1 in the adhesion between IRSL ECs and early EPCs. Therefore, the IRSL phenotype expressed in ECs may enhance neovascularization via increased homing of early EPCs. Our findings are first to implicate the complex effects of this phenotype on tumor neovascularization following irradiation. (author)

Endothelial RIG-I activation impairs endothelial function

International Nuclear Information System (INIS)

Asdonk, Tobias; Motz, Inga; Werner, Nikos; Coch, Christoph; Barchet, Winfried; Hartmann, Gunther; Nickenig, Georg; Zimmer, Sebastian

2012-01-01

Highlights: ► RIG-I activation impairs endothelial function in vivo. ► RIG-I activation alters HCAEC biology in vitro. ► EPC function is affected by RIG-I stimulation in vitro. -- Abstract: Background: Endothelial dysfunction is a crucial part of the chronic inflammatory atherosclerotic process and is mediated by innate and acquired immune mechanisms. Recent studies suggest that pattern recognition receptors (PRR) specialized in immunorecognition of nucleic acids may play an important role in endothelial biology in a proatherogenic manner. Here, we analyzed the impact of endothelial retinoic acid inducible gene I (RIG-I) activation upon vascular endothelial biology. Methods and results: Wild type mice were injected intravenously with 32.5 μg of the RIG-ligand 3pRNA (RNA with triphosphate at the 5′end) or polyA control every other day for 7 days. In 3pRNA-treated mice, endothelium-depended vasodilation was significantly impaired, vascular oxidative stress significantly increased and circulating endothelial microparticle (EMP) numbers significantly elevated compared to controls. To gain further insight in RIG-I dependent endothelial biology, cultured human coronary endothelial cells (HCAEC) and endothelial progenitor cells (EPC) were stimulated in vitro with 3pRNA. Both cells types express RIG-I and react with receptor upregulation upon stimulation. Reactive oxygen species (ROS) formation is enhanced in both cell types, whereas apoptosis and proliferation is not significantly affected in HCAEC. Importantly, HCAEC release significant amounts of proinflammatory cytokines in response to RIG-I stimulation. Conclusion: This study shows that activation of the cytoplasmatic nucleic acid receptor RIG-I leads to endothelial dysfunction. RIG-I induced endothelial damage could therefore be an important pathway in atherogenesis.

Autoantigens targeted in scleroderma patients with vascular disease are enriched in endothelial lineage cells

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McMahan, Zsuzsanna H.; Cottrell, Tricia R.; Wigley, Fredrick M.; Antiochos, Brendan; Zambidis, Elias T.; Park, Tea Soon; Halushka, Marc K.; Gutierrez-Alamillo, Laura; Cimbro, Raffaello; Rosen, Antony; Casciola-Rosen, Livia

2016-01-01

Objective Scleroderma patients with autoantibodies to centromere proteins (CENPs) and/or interferon-inducible protein 16 (IFI16) are at increased risk of severe vascular complications. We set out to define whether these autoantigens are enriched in cells of the vasculature. Methods Successive stages of embryoid bodies (EBs) as well as vascular progenitors were used to evaluate the expression of scleroderma autoantigens IFI16 and CENP by immunoblotting. CD31 was included to mark early blood vessels. IFI16 and CD31 expression were defined in skin paraffin sections from scleroderma patients and from healthy controls. IFI16 expression was determined by flow cytometry in circulating endothelial cells (CECs) and circulating progenitor cells (CPCs). Results Expression of CENP-A, IFI16 and CD31 was enriched in EBs at days 10 and 12 of differentiation, and particularly in cultures enriched in vascular progenitors (IFI16, CD31, CENPs A and-B). This pattern was distinct from that of comparator autoantigens. Immunohistochemical staining of skin paraffin sections showed enrichment of IFI16 in CD31-positive vascular endothelial cells in biopsies from scleroderma patients and normal controls. Flow cytometry analysis revealed IFI16 expression in CPCs, but minimal expression in CECs. Conclusion Expression of scleroderma autoantigens IFI16 and CENPs, which are associated with severe vascular disease, is increased in vascular progenitors and mature endothelial cells. High level, lineage-enriched expression of autoantigens may explain the striking association between clinical phenotypes and the immune targeting of specific autoantigens. PMID:27159521

Panax Notoginseng Saponins Promote Endothelial Progenitor Cell Mobilization and Attenuate Atherosclerotic Lesions in Apolipoprotein E Knockout Mice

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Ya Liu

2013-09-01

Full Text Available Background: Endothelial progenitor cells (EPCs derived from the bone marrow (BM play a key role in the homeostasis of vascular repair by enhanced reendothelialization. Panax notoginseng saponins (PNS, a highly valued traditional Chinese medicine, has been shown to reduce morbidity and mortality from coronary artery disease. The present research was designed to explore the contribution of progenitor cells to the progression of atherosclerotic plaques and the possible modulatory role of PNS in this process. Methods: PNS (60 or 120 mg/kg via intraperitoneal injection was administered over 8 weeks in apolipoprotein E knockout mice on an atherogenic diet. The sizes and histochemical alteration of atherosclerotic lesions and numbers of EPCs in BM and peripheral blood were analyzed. The expression of chemokine stromal cell-derived factor 1α (SDF-1α and its receptor, CXCR4, was monitored as well. Results: PNS significantly reduced the lesion area and intima-to-media ratio compared to vehicle treatment. PNS also augmented endothelialization and reduced the smooth muscle cell (SMCs content of the lesions. The number of c-kit and sca-1 double-positive progenitor cells and flk-1 and sca-1 double-positive progenitor cells were significantly increased in the BM and the peripheral blood of the PNS-treated groups. PNS treatment increased the plasma levels of SDF-1α and SCF as well as the BM levels of matrix metalloproteinase-9 (MMP-9. Moreover, the mRNA levels of SDF-1α and protein levels of CXCR4 were both increased in the BM of mice treated with PNS, while SDF-1α expression decreased. Conclusion: PNS reduce the size of atherosclerotic plaques, and this effect appears to involve progenitor cell mobilization. SDF-1α-CXCR4 interactions and the possible modulatory role of PNS in this process may contribute to the increased progenitor cell mobilization.

Endothelial Progenitor Cell Mobilization in Preterm Infants With Sepsis Is Associated With Improved Survival.

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Siavashi, Vahid; Asadian, Simin; Taheri-Asl, Masoud; Keshavarz, Samaneh; Zamani-Ahmadmahmudi, Mohamad; Nassiri, Seyed Mahdi

2017-10-01

Microvascular dysfunction plays a key role in the pathology of sepsis, leading to multi-organ failure, and death. Circulating endothelial progenitor cells (cEPCs) are critically involved in the maintenance of the vascular homeostasis in both physiological and pathological contexts. In this study, concentration of cEPCs in preterm infants with sepsis was determined to recognize whether the EPC mobilization would affect the clinical outcome of infantile sepsis. One hundred and thirty-three preterm infants (81 with sepsis and 52 without sepsis) were enrolled in this study. The release of EPCs in circulation was first quantified. Thereafter, these cells were cultivated and biological features of these cells such as, proliferation and colony forming efficiency were analyzed. The levels of chemoattractant cytokines were also measured in infants. In mouse models of sepsis, effects of VEGF and SDF-1 as well as anti-VEGF and anti-SDF-1 were evaluated in order to shed light upon the role which the EPC mobilization plays in the overall survival of septic animals. Circulating EPCs were significantly higher in preterm infants with sepsis than in the non-sepsis group. Serum levels of VEGF, SDF-1, and Angiopoietin-2 were also higher in preterm infants with sepsis than in control non-sepsis. In the animal experiments, injection of VEGF and SDF-1 prompted the mobilization of EPCs, leading to an improvement in survival whereas injection of anti-VEGF and anti-SDF-1 was associated with significant deterioration of survival. Overall, our results demonstrated the beneficial effects of EPC release in preterm infants with sepsis, with increased mobilization of these cells was associated with improved survival. J. Cell. Biochem. 118: 3299-3307, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

MRI of the transplanted endothelial progenitor cells for prevent atherosclerotic plaque formation

International Nuclear Information System (INIS)

Ma Zhanlong; Teng Gaojun; Mai Xiaoli; Chen Jun; Sun Junhui; Zhang Hongying; Yu Hui; Li Guozhao

2007-01-01

Objective: To evaluate the 1.5 T magnetic resonance imaging system to depict and track in vivo of magnetically labeled endothelial progenitor cells (EPCs), and to study the possibility for preventing the atherosclerotic plaque formation in New Zealand rabbit model of carotid arterial injury after transplantation. Methods: New Zealand rabbit EPCs were isolated, confirmed, expanded and then incubated with home synthesized Fe 2 O 3 -PLL, Prussian blue stain was performed for showing intracellular irons. The model of carotid arterial injury was performed by 2.5F balloons, the group A of 8 rabbits received magnetically labeled EPCs, group B of 3 rabbits received fluorescent-labeled EPCs and the group C of 5 rabbits were given same volume saline injection after endothelial injury of the carotid artery. MR imaging and histology were performed and compared 4 days later for randomly chosen three rabbit, each from one of the three group; all the other rabbits were fed with high lipid diet and examed using MR imaging and histology after 15 weeks. Results: Epcs labeling efficiency was more than 95% by Prussian blue stain, 4 days after transplantation of EPCs, only in group A, the injured endothelium of carotid artery had signal intensity loss in T 2 * WI, which were correlated well with the area where the most Prussian blue staining positive cells were found in histopathology analyses. The rabbits of group A and B which received EPCs transplantation exhibited fewer plaques formation than those of the group C (P 2 O 3 -PLL. The 1.5 T magnetic resonance imaging system could depict and monitor the magnetically labeled endothelial progenitor cells homing to the injured endothelium of the artery, and EPCs contribute to preventing atherosclerotic plaque formation in New Zealand rabbit model of atherosclerosis. (authors)

Endothelial Progenitor Cells in Diabetic Microvascular Complications: Friends or Foes?

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Yu, Cai-Guo; Zhang, Ning; Yuan, Sha-Sha; Ma, Yan; Yang, Long-Yan; Feng, Ying-Mei; Zhao, Dong

2016-01-01

Despite being featured as metabolic disorder, diabetic patients are largely affected by hyperglycemia-induced vascular abnormality. Accumulated evidence has confirmed the beneficial effect of endothelial progenitor cells (EPCs) in coronary heart disease. However, antivascular endothelial growth factor (anti-VEGF) treatment is the main therapy for diabetic retinopathy and nephropathy, indicating the uncertain role of EPCs in the pathogenesis of diabetic microvascular disease. In this review, we first illustrate how hyperglycemia induces metabolic and epigenetic changes in EPCs, which exerts deleterious impact on their number and function. We then discuss how abnormal angiogenesis develops in eyes and kidneys under diabetes condition, focusing on "VEGF uncoupling with nitric oxide" and "competitive angiopoietin 1/angiopoietin 2" mechanisms that are shared in both organs. Next, we dissect the nature of EPCs in diabetic microvascular complications. After we overview the current EPCs-related strategies, we point out new EPCs-associated options for future exploration. Ultimately, we hope that this review would uncover the mysterious nature of EPCs in diabetic microvascular disease for therapeutics.

Differentiation state determines neural effects on microvascular endothelial cells

International Nuclear Information System (INIS)

Muffley, Lara A.; Pan, Shin-Chen; Smith, Andria N.; Ga, Maricar; Hocking, Anne M.; Gibran, Nicole S.

2012-01-01

Growing evidence indicates that nerves and capillaries interact paracrinely in uninjured skin and cutaneous wounds. Although mature neurons are the predominant neural cell in the skin, neural progenitor cells have also been detected in uninjured adult skin. The aim of this study was to characterize differential paracrine effects of neural progenitor cells and mature sensory neurons on dermal microvascular endothelial cells. Our results suggest that neural progenitor cells and mature sensory neurons have unique secretory profiles and distinct effects on dermal microvascular endothelial cell proliferation, migration, and nitric oxide production. Neural progenitor cells and dorsal root ganglion neurons secrete different proteins related to angiogenesis. Specific to neural progenitor cells were dipeptidyl peptidase-4, IGFBP-2, pentraxin-3, serpin f1, TIMP-1, TIMP-4 and VEGF. In contrast, endostatin, FGF-1, MCP-1 and thrombospondin-2 were specific to dorsal root ganglion neurons. Microvascular endothelial cell proliferation was inhibited by dorsal root ganglion neurons but unaffected by neural progenitor cells. In contrast, microvascular endothelial cell migration in a scratch wound assay was inhibited by neural progenitor cells and unaffected by dorsal root ganglion neurons. In addition, nitric oxide production by microvascular endothelial cells was increased by dorsal root ganglion neurons but unaffected by neural progenitor cells. -- Highlights: ► Dorsal root ganglion neurons, not neural progenitor cells, regulate microvascular endothelial cell proliferation. ► Neural progenitor cells, not dorsal root ganglion neurons, regulate microvascular endothelial cell migration. ► Neural progenitor cells and dorsal root ganglion neurons do not effect microvascular endothelial tube formation. ► Dorsal root ganglion neurons, not neural progenitor cells, regulate microvascular endothelial cell production of nitric oxide. ► Neural progenitor cells and dorsal root

Benfotiamine counteracts glucose toxicity effects on endothelial progenitor cell differentiation via Akt/FoxO signaling.

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Marchetti, Valentina; Menghini, Rossella; Rizza, Stefano; Vivanti, Alessia; Feccia, Tiziana; Lauro, Davide; Fukamizu, Akiyoshi; Lauro, Renato; Federici, Massimo

2006-08-01

Dysfunction of mature endothelial cells is thought to play a major role in both micro- and macrovascular complications of diabetes. However, recent advances in biology of endothelial progenitor cells (EPCs) have highlighted their involvement in diabetes complications. To determine the effect of glucotoxicity on EPCs, human EPCs have been isolated from peripheral blood mononuclear cells of healthy donors and cultured in the presence or absence of high glucose (33 mmol/l) or high glucose plus benfotiamine to scavenge glucotoxicity. Morphological analysis revealed that high glucose significantly affected the number of endothelial cell colony forming units, uptake and binding of acLDL and Lectin-1, and the ability to differentiate into CD31- and vascular endothelial growth factor receptor 2-positive cells. Functional analysis outlined a reduced EPC involvement in de novo tube formation, when cocultured with mature endothelial cells (human umbilical vein endothelial cells) on matrigel. To explain the observed phenotypes, we have investigated the signal transduction pathways known to be involved in EPC growth and differentiation. Our results indicate that hyperglycemia impairs EPC differentiation and that the process can be restored by benfotiamine administration, via the modulation of Akt/FoxO1 activity.

Endothelial RIG-I activation impairs endothelial function

Energy Technology Data Exchange (ETDEWEB)

Asdonk, Tobias, E-mail: tobias.asdonk@ukb.uni-bonn.de [Department of Medicine/Cardiology, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn (Germany); Motz, Inga; Werner, Nikos [Department of Medicine/Cardiology, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn (Germany); Coch, Christoph; Barchet, Winfried; Hartmann, Gunther [Institute for Clinical Chemistry and Clinical Pharmacology, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn (Germany); Nickenig, Georg; Zimmer, Sebastian [Department of Medicine/Cardiology, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn (Germany)

2012-03-30

Highlights: Black-Right-Pointing-Pointer RIG-I activation impairs endothelial function in vivo. Black-Right-Pointing-Pointer RIG-I activation alters HCAEC biology in vitro. Black-Right-Pointing-Pointer EPC function is affected by RIG-I stimulation in vitro. -- Abstract: Background: Endothelial dysfunction is a crucial part of the chronic inflammatory atherosclerotic process and is mediated by innate and acquired immune mechanisms. Recent studies suggest that pattern recognition receptors (PRR) specialized in immunorecognition of nucleic acids may play an important role in endothelial biology in a proatherogenic manner. Here, we analyzed the impact of endothelial retinoic acid inducible gene I (RIG-I) activation upon vascular endothelial biology. Methods and results: Wild type mice were injected intravenously with 32.5 {mu}g of the RIG-ligand 3pRNA (RNA with triphosphate at the 5 Prime end) or polyA control every other day for 7 days. In 3pRNA-treated mice, endothelium-depended vasodilation was significantly impaired, vascular oxidative stress significantly increased and circulating endothelial microparticle (EMP) numbers significantly elevated compared to controls. To gain further insight in RIG-I dependent endothelial biology, cultured human coronary endothelial cells (HCAEC) and endothelial progenitor cells (EPC) were stimulated in vitro with 3pRNA. Both cells types express RIG-I and react with receptor upregulation upon stimulation. Reactive oxygen species (ROS) formation is enhanced in both cell types, whereas apoptosis and proliferation is not significantly affected in HCAEC. Importantly, HCAEC release significant amounts of proinflammatory cytokines in response to RIG-I stimulation. Conclusion: This study shows that activation of the cytoplasmatic nucleic acid receptor RIG-I leads to endothelial dysfunction. RIG-I induced endothelial damage could therefore be an important pathway in atherogenesis.

Circulating endothelial cells as marker of endothelial damage in male hypogonadism.

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Milardi, Domenico; Grande, Giuseppe; Giampietro, Antonella; Vendittelli, Francesca; Palumbo, Sara; Tartaglione, Linda; Marana, Riccardo; Pontecorvi, Alfredo; de Marinis, Laura; Zuppi, Cecilia; Capoluongo, Ettore

2012-01-01

Testosterone deficiency has become a frequently diagnosed condition in today's society affected by epidemic obesity, and is associated with cardiovascular risk. Recent studies have established the importance of altered vascular endothelium function in cardiovascular disease. The damage to the endothelium might also cause endothelial cell detachment, resulting in increased numbers of circulating endothelial cells (CEC) within the bloodstream. To evaluate whether hypogonadism could modify CEC count in peripheral bloodstream, we investigated peripheral blood CEC count using the CellSearch System, a semiautomatic method to accurately and reliably enumerate CECs, which are sorted based on a CD146(+), CD105(+), DAPI(+), CD45(-) phenotype, in a population of 20 patients with hypogonadism. The control group comprised 10 age- and sex-matched healthy participants. CEC count per milliliter was significantly increased in patients with hypogonadism vs the control group. In the group with hypogonadism, an inverse exponential correlation was present between testosterone levels and CEC count per milliliter. A direct linear correlation was present between waist circumference and CECs and between body mass index and CECs. The regression analysis showed that testosterone was the significant independent determinant of CECs. Our results underline that male hypogonadism is associated with endothelial dysfunction. The correlation between CEC and waist circumference underlines that visceral obesity may be synergically implicated in this regulation. Future studies are required to unveil the mechanisms involved in the pathogenesis of testosterone-induced endothelial disfunction, which may provide novel therapeutic targets to be incorporated in the management of hypogonadism.

Leukocyte- and endothelial-derived microparticles: a circulating source for fibrinolysis

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Lacroix, Romaric; Plawinski, Laurent; Robert, Stéphane; Doeuvre, Loïc; Sabatier, Florence; Martinez de Lizarrondo, Sara; Mezzapesa, Anna; Anfosso, Francine; Leroyer, Aurelie S.; Poullin, Pascale; Jourde, Noémie; Njock, Makon-Sébastien; Boulanger, Chantal M.; Anglés-Cano, Eduardo; Dignat-George, Françoise

2012-01-01

Background We recently assigned a new fibrinolytic function to cell-derived microparticles in vitro. In this study we explored the relevance of this novel property of microparticles to the in vivo situation. Design and Methods Circulating microparticles were isolated from the plasma of patients with thrombotic thrombocytopenic purpura or cardiovascular disease and from healthy subjects. Microparticles were also obtained from purified human blood cell subpopulations. The plasminogen activators on microparticles were identified by flow cytometry and enzyme-linked immunosorbent assays; their capacity to generate plasmin was quantified with a chromogenic assay and their fibrinolytic activity was determined by zymography. Results Circulating microparticles isolated from patients generate a range of plasmin activity at their surface. This property was related to a variable content of urokinase-type plasminogen activator and/or tissue plasminogen activator. Using distinct microparticle subpopulations, we demonstrated that plasmin is generated on endothelial and leukocyte microparticles, but not on microparticles of platelet or erythrocyte origin. Leukocyte-derived microparticles bear urokinase-type plasminogen activator and its receptor whereas endothelial microparticles carry tissue plasminogen activator and tissue plasminogen activator/inhibitor complexes. Conclusions Endothelial and leukocyte microparticles, bearing respectively tissue plasminogen activator or urokinase-type plasminogen activator, support a part of the fibrinolytic activity in the circulation which is modulated in pathological settings. Awareness of this blood-borne fibrinolytic activity conveyed by microparticles provides a more comprehensive view of the role of microparticles in the hemostatic equilibrium. PMID:22733025

Mechanism of endothelial progenitor cell recruitment into neo-vessels in adjacent non-tumor tissues in hepatocellular carcinoma

International Nuclear Information System (INIS)

Yu, De-cai; Chen, Jun; Sun, Xi-tai; Zhuang, Lin-yuan; Jiang, Chun-ping; Ding, Yi-tao

2010-01-01

We investigated the distribution and clinical significance of mobilized endothelial progenitor cells (EPCs) in hepatocellular carcinoma (HCC). We found that many more EPCs were recruited to nonmalignant liver tissue (especially into adjacent non-tumor tissues (AT)) than to tumor vessels. These results suggest that the mechanism underlying the recruitment of EPCs into microvessels in AT merits further investigation Angiogenic factors were detected in three tissue microarrays comprising normal liver, paired tumor tissue (TT) and AT from 105 patients (who had undergone hepatectomy for HCC) using immunohistochemistry. Also, the number of EPCs (positive for Sca-1, Flk-1 and c-Kit) in the blood and liver of cirrhotic mice were determined by flow cytometry and immunohistochemistry. The distribution of these labeled EPCs in tumor and non-tumor tissues was then studied. The results from the tissue microarrays showed that the expression levels of VEGF-A, bFGF, TGF-β, MCP-1, TSP-1, MMP-9, TIMP-2, and endostatin were significantly higher in AT than in either normal liver or TT (p < 0.05), but no significant difference was found in the expression levels of COX-2 and NOS-2 between AT and TT. The expression of VEGF-A, bFGF, TGF-β, MCP-1, TSP-1, MMP-9, TIMP-2, endostatin, COX-2, and NOS-2 in normal liver tissue was weaker than that in AT or TT. In cirrhotic mice, the number of circulating endothelial progenitor cells gradually increased, before decreasing again. In this mouse model, increased numbers of EPCs were recruited and homed specifically to the cirrhotic liver. Both liver cirrhosis and HCC led to increased expression of pro-angiogenic factors, which resulted in the recruitment of EPCs into AT. Also, EPCs were mobilized, recruited and homed to cirrhotic liver. The unique pathology of HCC coupled with liver cirrhosis may, therefore, be associated with the distribution and function of EPCs

Ticagrelor Improves Endothelial Function by Decreasing Circulating Epidermal Growth Factor (EGF

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Francesco Vieceli Dalla Sega

2018-04-01

Full Text Available Ticagrelor is one of the most powerful P2Y12 inhibitor. We have recently reported that, in patients with concomitant Stable Coronary Artery Disease (SCAD and Chronic Obstructive Pulmonary Disease (COPD undergoing percutaneous coronary intervention (PCI, treatment with ticagrelor, as compared to clopidogrel, is associated with an improvement of the endothelial function (Clinical Trial NCT02519608. In the present study, we showed that, in the same population, after 1 month treatment with ticagrelor, but not with clopidogrel, there is a decrease of the circulating levels of epidermal growth factor (EGF and that these changes in circulating levels of EGF correlate with on-treatment platelet reactivity. Furthermore, in human umbilical vein endothelial cells (HUVEC incubated with sera of the patients treated with ticagrelor, but not with clopidogrel there is an increase of p-eNOS levels. Finally, analyzing the changes in EGF and p-eNOS levels after treatment, we observed an inverse correlation between p-eNOS and EGF changes only in the ticagrelor group. Causality between EGF and eNOS activation was assessed in vitro in HUVEC where we showed that EGF decreases eNOS activity in a dose dependent manner. Taken together our data indicate that ticagrelor improves endothelial function by lowering circulating EGF that results in the activation of eNOS in the vascular endothelium.

Circulating vascular endothelial growth factor during the normal menstrual cycle

NARCIS (Netherlands)

Kusumanto, YH; Hospers, GAP; Sluiter, WJ; Dam, WA; Meijer, C; Mulder, NH

2004-01-01

Background: The purpose of the study was to investigate whether cycle-related variations in circulating Vascular Endothelial Growth Factor (VEGF) levels would increase the metastatic potential at specific times during the menstrual cycle. Materials and Methods: VEGF levels in serum and whole blood

Endothelial progenitor cells in mothers of low-birthweight infants: a link between defective placental vascularization and increased cardiovascular risk?

LENUS (Irish Health Repository)

King, Thomas F J

2013-01-01

Offspring birthweight is inversely associated with future maternal cardiovascular mortality, a relationship that has yet to be fully elucidated. Endothelial progenitor cells (EPCs) are thought to play a key role in vasculogenesis, and EPC numbers reflect cardiovascular risk.

Transplantation of endothelial progenitor cells ameliorates vascular dysfunction and portal hypertension in carbon tetrachloride-induced rat liver cirrhotic model.

Science.gov (United States)

Sakamoto, Masaharu; Nakamura, Toru; Torimura, Takuji; Iwamoto, Hideki; Masuda, Hiroshi; Koga, Hironori; Abe, Mitsuhiko; Hashimoto, Osamu; Ueno, Takato; Sata, Michio

2013-01-01

In cirrhosis, sinusoidal endothelial cell injury results in increased endothelin-1 (ET-1) and decreased nitric oxide synthase (NOS) activity, leading to portal hypertension. However, the effects of transplanted endothelial progenitor cells (EPCs) on the cirrhotic liver have not yet been clarified. We investigated whether EPC transplantation reduces portal hypertension. Cirrhotic rats were created by the administration of carbon tetrachloride (CCl(4) ) twice weekly for 10 weeks. From week 7, rat bone marrow-derived EPCs were injected via the tail vein in this model once a week for 4 weeks. Endothelial NOS (eNOS), vascular endothelial growth factor (VEGF) and caveolin expressions were examined by Western blots. Hepatic tissue ET-1 was measured by a radioimmunoassay (RIA). Portal venous pressure, mean aortic pressure, and hepatic blood flow were measured. Endothelial progenitor cell transplantation reduced liver fibrosis, α-smooth muscle actin-positive cells, caveolin expression, ET-1 concentration and portal venous pressure. EPC transplantation increased hepatic blood flow, protein levels of eNOS and VEGF. Immunohistochemical analyses of eNOS and isolectin B4 demonstrated that the livers of EPC-transplanted animals had markedly increased vascular density, suggesting reconstitution of sinusoidal blood vessels with endothelium. Transplantation of EPCs ameliorates vascular dysfunction and portal hypertension, suggesting this treatment may provide a new approach in the therapy of portal hypertension with liver cirrhosis. © 2012 Journal of Gastroenterology and Hepatology Foundation and Wiley Publishing Asia Pty Ltd.

Extracellular histones reduce survival and angiogenic responses of late outgrowth progenitor and mature endothelial cells.

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Mena, H A; Carestia, A; Scotti, L; Parborell, F; Schattner, M; Negrotto, S

2016-02-01

ESSENTIALS: Extracellular histones are highly augmented in sites of neovessel formation, such as regeneration tissues. We studied histone effect on survival and angiogenic activity of mature and progenitor endothelial cells. Extracellular histones trigger apoptosis and pyroptosis and reduce angiogenesis in vivo and in vitro. Histone blockade can be useful as a therapeutic strategy to improve angiogenesis and tissue regeneration. Extracellular histones are highly augmented in sites of neovessel formation, like regeneration tissues. Their cytotoxic effect has been studied in endothelial cells, although the mechanism involved and their action on endothelial colony-forming cells (ECFCs) remain unknown. To study the effect of histones on ECFC survival and angiogenic functions and compare it with mature endothelial cells. Nuclear morphology analysis showed that each human recombinant histone triggered both apoptotic-like and necrotic-like cell deaths in both mature and progenitor endothelial cells. While H1 and H2A exerted a weak toxicity, H2B, H3 and H4 were the most powerful. The percentage of apoptosis correlated with the percentage of ECFCs exhibiting caspase-3 activation and was zeroed by the pan-caspase inhibitor Z-VAD-FMK. Necrotic-like cell death was also suppressed by this compound and the caspase-1 inhibitor Ac-YVAD-CMK, indicating that histones triggered ECFC pyroptosis. All histones, at non-cytotoxic concentrations, reduced migration and H2B, H3 and H4 induced cell cycle arrest and impaired tubulogenesis via p38 activation. Neutrophil-derived histones exerted similar effects. In vivo blood vessel formation in the quail chorioallantoic membrane was also reduced by H2B, H3 and H4. Their cytotoxic and antiangiogenic effects were suppressed by unfractioned and low-molecular-weight heparins and the combination of TLR2 and TLR4 blocking antibodies. Histones trigger both apoptosis and pyroptosis of ECFCs and inhibit their angiogenic functions. Their cytotoxic and

Opportunities and Challenges for Repair of Macrovascular Disease using Circulating Blood-Derived Progenitor Cells

OpenAIRE

Loeken, Mary R.

2014-01-01

There are currently few solutions for diabetic vascular disease that involve repair of damaged tissues. The manuscript by Porat, et al., suggests a possible method to use a patient’s own circulating blood cells to provide progenitors to repair damaged vascular tissues.

Intratracheal transplantation of endothelial progenitor cells attenuates smoking-induced COPD in mice

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Shi Z

2017-03-01

Full Text Available Zhihui Shi,1 Yan Chen,1 Jun Cao,2 Huihui Zeng,1 Yue Yang,1 Ping Chen,1 Hong Luo,1 Hong Peng,1 Shan Cai,1 Chaxiang Guan3 1Department of Internal Medicine, Division of Respiratory Disease, The Second Xiangya Hospital, Central-South University, 2Department of Internal Medicine, Division of Respiratory Disease, The People’s Hospital of Hunan Province, 3Department of Physiology, Xiangya Medical School, Central-South University, Changsha, Hunan, People’s Republic of China Background: Endothelial progenitor cells (EPCs might play a protective role in COPD. The aim of this study was to investigate whether intratracheal allogeneic transplantation of bone-marrow-derived EPCs would attenuate the development of smoking-induced COPD in mice.Methods: Isolated mononuclear cells from the bone marrow of C57BL/6J mice were cultured in endothelial cell growth medium-2 for 10 days, yielding EPCs. A murine model of COPD was established by passive 90-day exposure of cigarette smoke. On day 30, EPCs or phosphate-buffered saline alone was administered into the trachea. On day 90, EPCs or 30 µL phosphate-buffered saline alone was administered into the trachea, and on day 120, inflammatory cells, antioxidant activity, apoptosis, matrix metalloproteinase (MMP-2, and MMP-9 were measured.Results: After EPC treatment, the lung function of the mice had improved compared with the untreated mice. Mean linear intercept and destructive index were reduced in the EPCs-treated group compared with the untreated group. In addition, the EPCs-treated mice exhibited less antioxidant activity in bronchoalveolar lavage fluid compared with the untreated mice. Moreover, decreased activities of MMP-2, MMP-9, and TUNEL-positive cells in lung tissues were detected in EPCs-treated mice.Conclusion: Intratracheal transplantation of EPCs attenuated the development of pulmonary emphysema and lung function disorder probably by alleviating inflammatory infiltration, decelerating apoptosis

Endothelial Progenitor Cell Dysfunction in Polycystic Ovary Syndrome: Implications for The Genesis of Cardiovascular Diseases

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Yu-Hsun Kao

2013-01-01

Full Text Available Polycystic ovary syndrome (PCOS, the most common endocrine disorder affecting women ofreproductive age, is characterized by hyperandrogenism and insulin resistance. Women withPCOS have a higher risk for cardiovascular diseases (CVDs and endothelial dysfunction. Themechanisms underlying these risks are unclear. Human peripheral blood contains circulatingendothelial progenitor cells (EPCs derived from bone marrow that have the ability to proliferate anddifferentiate into mature endothelial cells, which may contribute to vessel homeostasis and repair.PCOS is associated with insulin resistance, hyperinsulinemia, and dyslipidemia, which may resultin EPC dysfunction. In this review, we summarize the potential mechanisms of EPC dysfunction inPCOS, which possibly result in a higher genesis of CVDs in PCOS-affected subjects.

Endothelial jagged-2 sustains hematopoietic stem and progenitor reconstitution after myelosuppression.

Science.gov (United States)

Guo, Peipei; Poulos, Michael G; Palikuqi, Brisa; Badwe, Chaitanya R; Lis, Raphael; Kunar, Balvir; Ding, Bi-Sen; Rabbany, Sina Y; Shido, Koji; Butler, Jason M; Rafii, Shahin

2017-12-01

Angiocrine factors, such as Notch ligands, supplied by the specialized endothelial cells (ECs) within the bone marrow and splenic vascular niche play an essential role in modulating the physiology of adult hematopoietic stem and progenitor cells (HSPCs). However, the relative contribution of various Notch ligands, specifically jagged-2, to the homeostasis of HSPCs is unknown. Here, we show that under steady state, jagged-2 is differentially expressed in tissue-specific vascular beds, but its expression is induced in hematopoietic vascular niches after myelosuppressive injury. We used mice with EC-specific deletion of the gene encoding jagged-2 (Jag2) to demonstrate that while EC-derived jagged-2 was dispensable for maintaining the capacity of HSPCs to repopulate under steady-state conditions, by activating Notch2 it did contribute to the recovery of HSPCs in response to myelosuppressive conditions. Engraftment and/or expansion of HSPCs was dependent on the expression of endothelial-derived jagged-2 following myeloablation. Additionally, jagged-2 expressed in bone marrow ECs regulated HSPC cell cycle and quiescence during regeneration. Endothelial-deployed jagged-2 triggered Notch2/Hey1, while tempering Notch2/Hes1 signaling in HSPCs. Collectively, these data demonstrate that EC-derived jagged-2 activates Notch2 signaling in HSPCs to promote hematopoietic recovery and has potential as a therapeutic target to accelerate balanced hematopoietic reconstitution after myelosuppression.

Autophagy promotes degradation of polyethyleneimine–alginate nanoparticles in endothelial progenitor cells

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Wang GD

2017-09-01

Full Text Available Guo-dong Wang, Yu-zhen Tan, Hai-jie Wang, Pei Zhou Department of Anatomy, Histology and Embryology, Shanghai Medical School of Fudan University, Shanghai, China Abstract: Polyethyleneimine (PEI–alginate (Alg nanoparticle (NP is a safe and effective vector for delivery of siRNA or DNA. Recent studies suggest that autophagy is related to cytotoxicity of PEI NPs. However, contribution of autophagy to degradation of PEI–Alg NPs remains unknown. CD34+VEGFR-3+ endothelial progenitor cells isolated from rat bone marrow were treated with 25 kDa branched PEI modified by Alg. After treatment with the NPs, morphological changes and distribution of the NPs in the cells were examined with scanning and transmission electron microscopies. Cytotoxicity of the NPs was analyzed by reactive oxygen species (ROS production, lactate dehydrogenase leakage and induction of apoptosis. The level of autophagy was assessed with expression of Beclin-1 and LC3 and formation of autophagic structures and amphisomes. Colocalization of LC3-positive puncta and the NPs was determined by LC3–GFP tracing. Cytotoxicity of PEI NPs was reduced greatly after modification with Alg. PEI–Alg NPs were distributed in mitochondria, rough endoplasmic reticula and nuclei as well as cytoplasm. After phagocytosis of the NPs, expression of Beclin-1 mRNA and LC3 protein was upregulated, and the number of LC3-positive puncta, autophagic structures and amphisomes increased significantly. The number of lysosomes also increased obviously. There were LC3-positive puncta in nuclei, and some puncta were colocalized with the NPs. These results demonstrate that the activated autophagy promotes degradation of PEI–Alg NPs via multiple pathways. Keywords: polyethyleneimine, alginate, nanoparticles, endothelial progenitor cells, autophagy

GroEL1, a heat shock protein 60 of Chlamydia pneumoniae, impairs neovascularization by decreasing endothelial progenitor cell function.

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Yi-Wen Lin

Full Text Available The number and function of endothelial progenitor cells (EPCs are sensitive to hyperglycemia, hypertension, and smoking in humans, which are also associated with the development of atherosclerosis. GroEL1 from Chlamydia pneumoniae has been found in atherosclerotic lesions and is related to atherosclerotic pathogenesis. However, the actual effects of GroEL1 on EPC function are unclear. In this study, we investigate the EPC function in GroEL1-administered hind limb-ischemic C57BL/B6 and C57BL/10ScNJ (a toll-like receptor 4 (TLR4 mutation mice and human EPCs. In mice, laser Doppler imaging, flow cytometry, and immunohistochemistry were used to evaluate the degree of neo-vasculogenesis, circulating level of EPCs, and expression of CD34, vWF, and endothelial nitric oxide synthase (eNOS in vessels. Blood flow in the ischemic limb was significantly impaired in C57BL/B6 but not C57BL/10ScNJ mice treated with GroEL1. Circulating EPCs were also decreased after GroEL1 administration in C57BL/B6 mice. Additionally, GroEL1 inhibited the expression of CD34 and eNOS in C57BL/B6 ischemic muscle. In vitro, GroEL1 impaired the capacity of differentiation, mobilization, tube formation, and migration of EPCs. GroEL1 increased senescence, which was mediated by caspases, p38 MAPK, and ERK1/2 signaling in EPCs. Furthermore, GroEL1 decreased integrin and E-selectin expression and induced inflammatory responses in EPCs. In conclusion, these findings suggest that TLR4 and impaired NO-related mechanisms could contribute to the reduced number and functional activity of EPCs in the presence of GroEL1 from C. pneumoniae.

Fetal exposure to a diabetic intrauterine environment resulted in a failure of cord blood endothelial progenitor cell adaptation against chronic hypoxia

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Dincer UD

2014-12-01

Full Text Available U Deniz Dincer Department of Basic and Clinical Pharmacology, School of Medicine, Bezmialem Vakif University (BAVU, Fatih/Istanbul, Turkey Abstract: Gestational diabetes mellitus (GDM has long-term health consequences, and fetal exposure to a diabetic intrauterine environment increases cardiovascular risk for her adult offspring. Some part of this could be related to their endothelial progenitor cells (EPCs. Understanding the vessel-forming ability of human umbilical cord blood (HUCB-derived endothelial colony-forming cells (ECFCs against pathological stress such as GDM response to hypoxia could generate new therapeutic strategies. This study aims to investigate the role of chronic hypoxia in EPCs functional and vessel-forming ability in GDM subjects. Each ECFC was expressed in endothelial and pro-angiogenic specific markers, namely endothelial nitric oxide synthase (eNOS, platelet (PECAM-1 endothelial cell adhesion molecule 1, vascular endothelial-cadherin CdH5 (Ca-dependent cell adhesion molecule, vascular endothelial growth factor A, (VEGFA and insulin-like growth factor 1 (IGF1. Chronic hypoxia did not affect CdH5, but PECAM1 MRNA expressions were increased in control and GDM subjects. Control hypoxic and GDM normoxic VEGFA MRNA expressions and hypoxia-inducible factor 1-alpha (HIF1α protein expressions were significantly increased in HUCB ECFCs. GDM resulted in most failure of HUCB ECFC adaptation and eNOS protein expressions against chronic hypoxia. Chronic hypoxia resulted in an overall decline in HUCB ECFCs' proliferative ability due to reduction of clonogenic capacity and diminished vessel formation. Furthermore, GDM also resulted in most failure of cord blood ECFC adaptation against chronic hypoxic environment. Keywords: endothelial progenitor cells, gestational diabetes mellitus, chronic hypoxia, human cord blood

Successful in vitro expansion and differentiation of cord blood derived CD34+ cells into early endothelial progenitor cells reveals highly differential gene expression.

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Ingo Ahrens

Full Text Available Endothelial progenitor cells (EPCs can be purified from peripheral blood, bone marrow or cord blood and are typically defined by a limited number of cell surface markers and a few functional tests. A detailed in vitro characterization is often restricted by the low cell numbers of circulating EPCs. Therefore in vitro culturing and expansion methods are applied, which allow at least distinguishing two different types of EPCs, early and late EPCs. Herein, we describe an in vitro culture technique with the aim to generate high numbers of phenotypically, functionally and genetically defined early EPCs from human cord blood. Characterization of EPCs was done by flow cytometry, immunofluorescence microscopy, colony forming unit (CFU assay and endothelial tube formation assay. There was an average 48-fold increase in EPC numbers. EPCs expressed VEGFR-2, CD144, CD18, and CD61, and were positive for acetylated LDL uptake and ulex lectin binding. The cells stimulated endothelial tube formation only in co-cultures with mature endothelial cells and formed CFUs. Microarray analysis revealed highly up-regulated genes, including LL-37 (CAMP, PDK4, and alpha-2-macroglobulin. In addition, genes known to be associated with cardioprotective (GDF15 or pro-angiogenic (galectin-3 properties were also significantly up-regulated after a 72 h differentiation period on fibronectin. We present a novel method that allows to generate high numbers of phenotypically, functionally and genetically characterized early EPCs. Furthermore, we identified several genes newly linked to EPC differentiation, among them LL-37 (CAMP was the most up-regulated gene.

Physiologic ischaemic training induces endothelial progenitor cell mobilization and myocardial angiogenesis via endothelial nitric oxide synthase related pathway in rabbits.

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Xiao, Mingyue; Lu, Xiao; Li, Jianan; Li, Ling; Li, Yongxue

2014-04-01

Ischaemia-induced angiogenesis promises to improve neovascularization by delivery of angiogenic factors or endothelial progenitor cells (EPCs) to cardiac ischaemic areas. In order to avoid the risk of excessive myocardial ischaemia, therefore, we hypothesized that physiological ischaemic training (PIT) of normal skeletal muscle might contribute to myocardial angiogenesis via nitric oxide mediated mobilization of EPCs from the bone marrow in the established rabbit model of controllable myocardial ischaemia. The rabbits were grouped by sham-operation, myocardial ischaemia without PIT, PIT and PIT with pretreatment with the endothelial nitric oxide synthase (eNOS) inhibitor L-nitroarginine methyl ester (L-NAME). Controlled myocardial ischaemia was modelled by a water balloon constrictor implanted on the left ventricular branch in a rabbit. The PIT procedure included three cycles of 3 min of cuff inflation followed by 5 min of deflation on hind limbs of the rabbits for 4 weeks. At the endpoints, circulating EPCs (CD34/Flk-1) were measured by fluorescence-activated cell sorter; capillary density, by immunohistochemistry; blood flow, by a microsphere technique; endothelial nitric oxide synthase (eNOS) mRNA and protein, by real-time reverse transcriptase (RT)-PCR and Western blotting. The mRNA levels of eNOS were significantly higher in the PIT and L-NAME groups than in the sham-operation group (P < 0.05). Phospho-eNOS protein expression was higher in the PIT group than in the sham-operation and myocardial ischaemia without PIT groups (P < 0.05), and the effect was inhibited by L-NAME pretreatment (P < 0.05). Compared with sham-operation and myocardial ischaemia without PIT groups, the PIT group had the highest EPC count (P < 0.001), and the increase of capillary density (P < 0.01) and collateral blood flow (P < 0.05) in the ischaemic myocardium was consistent with the finding of EPC count. These effects were also inhibited by pretreatment with

The Use of Endothelial Progenitor Cells for the Regeneration of Musculoskeletal and Neural Tissues

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Naosuke Kamei

2017-01-01

Full Text Available Endothelial progenitor cells (EPCs derived from bone marrow and blood can differentiate into endothelial cells and promote neovascularization. In addition, EPCs are a promising cell source for the repair of various types of vascularized tissues and have been used in animal experiments and clinical trials for tissue repair. In this review, we focused on the kinetics of endogenous EPCs during tissue repair and the application of EPCs or stem cell populations containing EPCs for tissue regeneration in musculoskeletal and neural tissues including the bone, skeletal muscle, ligaments, spinal cord, and peripheral nerves. EPCs can be mobilized from bone marrow and recruited to injured tissue to contribute to neovascularization and tissue repair. In addition, EPCs or stem cell populations containing EPCs promote neovascularization and tissue repair through their differentiation to endothelial cells or tissue-specific cells, the upregulation of growth factors, and the induction and activation of endogenous stem cells. Human peripheral blood CD34(+ cells containing EPCs have been used in clinical trials of bone repair. Thus, EPCs are a promising cell source for the treatment of musculoskeletal and neural tissue injury.

Prognostic Value of CD109+ Circulating Endothelial Cells in Recurrent Glioblastomas Treated with Bevacizumab and Irinotecan

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Cuppini, Lucia; Calleri, Angelica; Bruzzone, Maria Grazia; Prodi, Elena; Anghileri, Elena; Pellegatta, Serena; Mancuso, Patrizia; Porrati, Paola; Di Stefano, Anna Luisa; Ceroni, Mauro; Bertolini, Francesco; Finocchiaro, Gaetano; Eoli, Marica

2013-01-01

Background Recent data suggest that circulating endothelial and progenitor cells (CECs and CEPs, respectively) may have predictive potential in cancer patients treated with bevacizumab, the antibody recognizing vascular endothelial growth factor (VEGF). Here we report on CECs and CEPs investigated in 68 patients affected by recurrent glioblastoma (rGBM) treated with bevacizumab and irinotecan and two Independent Datasets of rGBM patients respectively treated with bevacizumab alone (n=32, independent dataset A: IDA) and classical antiblastic chemotherapy (n=14, independent dataset B: IDB). Methods rGBM patients with KPS ≥50 were treated until progression, as defined by MRI with RANO criteria. CECs expressing CD109, a marker of tumor endothelial cells, as well as other CEC and CEP subtypes, were investigated by six-color flow cytometry. Results A baseline count of CD109+ CEC higher than 41.1/ml (1st quartile) was associated with increased progression free survival (PFS; 20 versus 9 weeks, P=0.008) and overall survival (OS; 32 versus 23 weeks, P=0.03). Longer PFS (25 versus 8 weeks, P=0.02) and OS (27 versus 17 weeks, P=0.03) were also confirmed in IDA with CD109+ CECs higher than 41.1/ml but not in IDB. Patients treated with bevacizumab with or without irinotecan that were free from MRI progression after two months of treatment had significant decrease of CD109+ CECs: median PFS was 19 weeks; median OS 29 weeks. The presence of two non-contiguous lesions (distant disease) at baseline was an independent predictor of shorter PFS and OS (P<0.001). Conclusions Data encourage further studies on the predictive potential of CD109+ CECs in GBM patients treated with bevacizumab. PMID:24069296

Kalirin and CHD7: novel endothelial dysfunction indicators in circulating extracellular vesicles from hypertensive patients with albuminuria

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de la Cuesta, Fernando; Baldan-Martin, Montserrat; Moreno-Luna, Rafael; Alvarez-Llamas, Gloria; Gonzalez-Calero, Laura; Mourino-Alvarez, Laura; Sastre-Oliva, Tamara; López, Juan A.; Vázquez, Jesús; Ruiz-Hurtado, Gema; Segura, Julian; Vivanco, Fernando; Ruilope, Luis M.; Barderas, Maria G.

2017-01-01

Despite of the great advances in anti-hypertensive therapies, many patients under Renin-Angiotensin- System (RAS) suppression develop albuminuria, which is a clear indicator of therapeutic inefficiency. Hence, indicators of vascular function are needed to assess patients’ condition and help deciding future therapies. Proteomic analysis of circulating extracellular vesicles (EVs) showed two proteins, kalirin and chromodomain-helicase-DNA-binding protein 7 (CHD7), increased in albuminuric patients. A positive correlation of both with the expression of the endothelial activation marker E-selectin was found in EVs. In vitro analysis using TNFα-treated adult human endothelial cells proved their involvement in endothelial cell activation. Hence, we propose protein levels of kalirin and CHD7 in circulating EVs as novel endothelial dysfunction markers to monitor vascular condition in hypertensive patients with albuminuria. PMID:28152519

Effect of vitamin D on endothelial progenitor cells function.

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Yoav Hammer

Full Text Available Endothelial progenitor cells (EPCs are a population of bone marrow-derived cells, which have an important role in the process of endothelialization and vascular repair following injury. Impairment of EPCs, which occurs in patients with diabetes, was shown to be related to endothelial dysfunction, coronary artery disease (CAD and adverse clinical outcomes. Recent evidence has shown that calcitriol, the active hormone of vitamin D, has a favorable impact on the endothelium and cardiovascular system. There is limited data on the effect of vitamin D on EPCs function.To examine the in vitro effects of Calcitriol on EPCs from healthy subjects and patients with diabetes.Fifty-one patients with type 2 diabetes (60±11 years, 40% women, HbA1C: 9.1±0.8% and 23 healthy volunteers were recruited. EPCs were isolated and cultured with and without calcitriol. The capacity of the cells to form colony-forming units (CFUs, their viability (measured by MTT assay, KLF-10 levels and angiogenic markers were evaluated after 1 week of culture.In diabetic patients, EPC CFUs and cell viability were higher in EPCs exposed to calcitriol vs. EPCs not exposed to calcitriol [EPC CFUs: 1.25 (IQR 1.0-2.0 vs. 0.5 (IQR 0.5-1.9, p < 0.001; MTT:0.62 (IQR 0.44-0.93 vs. 0.52 (IQR 0.31-0.62, p = 0.001]. KLF-10 levels tended to be higher in EPCs exposed to vitamin D, with no differences in angiopoietic markers. In healthy subjects, calcitriol supplementation also resulted in higher cell viability [MTT: 0.23 (IQR 0.11-0.46 vs. 0.19 (0.09-0.39, p = 0.04], but without differences in CFU count or angiopoietic markers.In patients with diabetes mellitus, in vitro vitamin D supplementation improved EPCs capacity to form colonies and viability. Further studies regarding the mechanisms by which vitamin D exerts its effect are required.

Effects of benazepril on functional activity of endothelial progenitor cells from hypertension patients.

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Li, Yongdong; Alatan, Gaole; Ge, Zhiping; Liu, Dan

2014-01-01

The effect of angiotensin-converting enzyme inhibitors on hypertension patients regarding endothelial progenitor cell (EPC) functions is poorly understood. The aim of this study was to investigate the effects of benazepril on the proliferation, adhesion and migration capacity of EPCs and its possible mechanism. The functions of EPCs from hypertension patients were obviously reduced compared with control group, and this could be improved by benazepril in a dose-dependent manner, whereas this improvement were obviously blocked when AMD3100 were used together. Therefore, benazepril could obviously improve functions of EPCs from hypertension patients, and the potential mechanism may be related to SDF-1/CXCR4 axis.

Adhesion behavior of endothelial progenitor cells to endothelial cells in simple shear flow

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Gong, Xiao-Bo; Li, Yu-Qing; Gao, Quan-Chao; Cheng, Bin-Bin; Shen, Bao-Rong; Yan, Zhi-Qiang; Jiang, Zong-Lai

2011-12-01

The adhesion of endothelial progenitor cells (EPCs) on endothelial cells (ECs) is one of the critical physiological processes for the regenesis of vascular vessels and the prevention of serious cardiovascular diseases. Here, the rolling and adhesion behavior of EPCs on ECs was studied numerically. A two-dimensional numerical model was developed based on the immersed boundary method for simulating the rolling and adhesion of cells in a channel flow. The binding force arising from the catch bond of a receptor and ligand pair was modeled with stochastic Monte Carlo method and Hookean spring model. The effect of tumor necrosis factor alpha (TNF- α) on the expression of the number of adhesion molecules in ECs was analyzed experimentally. A flow chamber system with CCD camera was set up to observe the top view of the rolling of EPCs on the substrate cultivated with ECs. Numerical results prove that the adhesion of EPC on ECs is closely related to membrane stiffness of the cell and shear rate of the flow. It also suggests that the adhesion force between EPC and EC by P-selectin glycoprotein ligand-1 only is not strong enough to bond the cell onto vessel walls unless contributions of other catch bond are considered. Experimental results demonstrate that TNF- α enhanced the expressions of VCAM, ICAM, P-selectin and E-selectin in ECs, which supports the numerical results that the rolling velocity of EPC on TNF- α treated EC substrate decreases obviously compared with its velocity on the untreated one. It is found that because the adhesion is affected by both the rolling velocity and the deformability of the cell, an optimal stiffness of EPC may exist at a given shear rate of flow for achieving maximum adhesion rates.

Depletion of NAD pool contributes to impairment of endothelial progenitor cell mobilization in diabetes.

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Wang, Pei; Yang, Xi; Zhang, Zheng; Song, Jie; Guan, Yun-Feng; Zou, Da-Jin; Miao, Chao-Yu

2016-06-01

The impaired mobilization of endothelial progenitor cells (EPCs) from bone marrow (BM) critically contributes to the diabetes-associated vascular complications. Here, we investigated the relationship between the nicotinamide phosphoribosyltransferase (NAMPT)-controlled nicotinamide adenine dinucleotide (NAD) metabolism and the impaired mobilization of BM-derived EPCs in diabetic condition. The NAMPT-NAD pool in BM and BM-derived EPCs in wild-type (WT) and diabetic db/db mice was determined. Nicotinamide, a natural substrate for NAD biosynthesis, was administrated for 2weeks in db/db mice to examine the influence of enhancing NAD pool on BM and blood EPCs number. The modulations of stromal cell-derived factor-1α (SDF-1α) and endothelial nitric oxide synthase (eNOS) protein in BM were measured using immunoblotting. The EPCs intracellular NAMPT level and NAD concentration, as well as the blood EPCs number, were compared between 9 healthy people and 16 patients with type 2 diabetes mellitus (T2DM). The T2DM patients were treated with nicotinamide for two weeks and then the blood EPCs number was determined. Moreover, the association between blood EPCs numbers and EPCs intracellular NAD(+)/NAMPT protein levels in 21 healthy individuals was determined. We found that NAD concentration and NAMPT expression in BM and BM-derived EPCs of db/db mice were significantly lower than those in WT mice BM. Enhancing NAD pool not only increased the EPCs intracellular NAD concentration and blood EPCs number, but also improved post-ischemic wound healing and blood reperfusion in db/db mice with hind-limb ischemia model. Enhancing NAD pool rescued the impaired modulations of stromal cell-derived factor-1α (SDF-1α) and endothelial nitric oxide synthase (eNOS) protein levels in db/db mice BM upon hind-limb ischemia. In addition, enhancing NAD pool significantly inhibited PARP and caspase-3 activates in db/db mice BM. The intracellular NAMPT-NAD pool was positively associated with blood

Myocardial regeneration by transplantation of modified endothelial progenitor cells expressing SDF-1 in a rat model

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Schuh, A.; Kroh, A.; Konschalla, S.

2012-01-01

Cell based therapy has been shown to attenuate myocardial dysfunction after myocardial infarction (MI) in different acute and chronic animal models. It has been further shown that stromal-cell derived factor-1a (SDF-1a) facilitates proliferation and migration of endogenous progenitor cells...... into injured tissue. The aim of the present study was to investigate the role of exogenously applied and endogenously mobilized cells in a regenerative strategy for MI therapy. Lentivirally SDF-1a-infected endothelial progenitor cells (EPCs) were injected after 90 min. of ligation and reperfusion of the left...... compared to medium control. Intracoronary application of cells did not lead to significant differences compared to medium injected control hearts. Histology showed a significantly elevated rate of apoptotic cells and augmented proliferation after transplantation of EPCs and EPCs + SDF-1 alpha in infarcted...

A Fermented Whole Grain Prevents Lipopolysaccharides-Induced Dysfunction in Human Endothelial Progenitor Cells

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Laura Giusti

2017-01-01

Full Text Available Endogenous and exogenous signals derived by the gut microbiota such as lipopolysaccharides (LPS orchestrate inflammatory responses contributing to development of the endothelial dysfunction associated with atherosclerosis in obesity, metabolic syndrome, and diabetes. Endothelial progenitor cells (EPCs, bone marrow derived stem cells, promote recovery of damaged endothelium playing a pivotal role in cardiovascular repair. Since healthy nutrition improves EPCs functions, we evaluated the effect of a fermented grain, Lisosan G (LG, on early EPCs exposed to LPS. The potential protective effect of LG against LPS-induced alterations was evaluated as cell viability, adhesiveness, ROS production, gene expression, and NF-kB signaling pathway activation. Our results showed that LPS treatment did not affect EPCs viability and adhesiveness but induced endothelial alterations via activation of NF-kB signaling. LG protects EPCs from inflammation as well as from LPS-induced oxidative and endoplasmic reticulum (ER stress reducing ROS levels, downregulating proinflammatory and proapoptotic factors, and strengthening antioxidant defense. Moreover, LG pretreatment prevented NF-kB translocation from the cytoplasm into the nucleus caused by LPS exposure. In human EPCs, LPS increases ROS and upregulates proinflammatory tone, proapoptotic factors, and antioxidants. LG protects EPCs exposed to LPS reducing ROS, downregulating proinflammatory and proapoptotic factors, and strengthening antioxidant defenses possibly by inhibiting NF-κB nuclear translocation.

Neuroblast survival depends on mature vascular network formation after mouse stroke: role of endothelial and smooth muscle progenitor cell co-administration.

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Nih, Lina R; Deroide, Nicolas; Leré-Déan, Carole; Lerouet, Dominique; Soustrat, Mathieu; Levy, Bernard I; Silvestre, Jean-Sébastien; Merkulova-Rainon, Tatiana; Pocard, Marc; Margaill, Isabelle; Kubis, Nathalie

2012-04-01

Pro-angiogenic cell-based therapies constitute an interesting and attractive approach to enhancing post-stroke neurogenesis and decreasing neurological deficit. However, most new stroke-induced neurons die during the first few weeks after ischemia, thus impairing total recovery. Although the neovascularization process involves different cell types and various growth factors, most cell therapy protocols are based on the biological effects of single-cell-type populations or on the administration of heterogeneous populations of progenitors, namely human cord blood-derived CD34(+) cells, with scarce vascular progenitor cells. Tight cooperation between endothelial cells and smooth muscle cells/pericytes is critical for the development of functional neovessels. We hypothesized that neuroblast survival in stroke brain depends on mature vascular network formation. In this study, we injected a combination of endothelial progenitor cells (EPCs) and smooth muscle progenitor cells (SMPCs), isolated from human umbilical cord blood, into a murine model of permanent focal ischemia induced by middle cerebral artery occlusion. The co-administration of SMPCs and EPCs induced enhanced angiogenesis and vascular remodeling in the peri-infarct and infarct areas, where vessels exhibited a more mature phenotype. This activation of vessel growth resulted in the maintenance of neurogenesis and neuroblast migration to the peri-ischemic cortex. Our data suggest that a mature vascular network is essential for neuroblast survival after cerebral ischemia, and that co-administration of EPCs and SMPCs may constitute a novel therapeutic strategy for improving the treatment of stroke. © 2012 The Authors. European Journal of Neuroscience © 2012 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.

Contribution of endothelial progenitors and proangiogenic hematopoietic cells to vascularization of tumor and ischemic tissue

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Kopp, Hans-Georg; Ramos, Carlos A.; Rafii, Shahin

2010-01-01

Purpose of review During the last several years, a substantial amount of evidence from animal as well as human studies has advanced our knowledge of how bone marrow derived cells contribute to neoangiogenesis. In the light of recent findings, we may have to redefine our thinking of endothelial cells as well as of perivascular mural cells. Recent findings Inflammatory hematopoietic cells, such as macrophages, have been shown to promote neoangiogenesis during tumor growth and wound healing. Dendritic cells, B lymphocytes, monocytes, and other immune cells have also been found to be recruited to neoangiogenic niches and to support neovessel formation. These findings have led to the concept that subsets of hematopoietic cells comprise proangiogenic cells that drive adult revascularization processes. While evidence of the importance of endothelial progenitor cells in adult vasculogenesis increased further, the role of these comobilized hematopoietic cells has been intensely studied in the last few years. Summary Angiogenic factors promote mobilization of vascular endothelial growth factor receptor 1-positive hematopoietic cells through matrix metalloproteinase-9 mediated release of soluble kit-ligand and recruit these proangiogenic cells to areas of hypoxia, where perivascular mural cells present stromal-derived factor 1 (CXCL-12) as an important retention signal. The same factors are possibly involved in mobilization of vascular endothelial growth factor receptor 2-positive endothelial precursors that may participate in neovessel formation. The complete characterization of mechanisms, mediators and signaling pathways involved in these processes will provide novel targets for both anti and proangiogenic therapeutic strategies. PMID:16567962

Circulating Endothelial Microparticles: A Key Hallmark of Atherosclerosis Progression

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Keshav Raj Paudel

2016-01-01

Full Text Available The levels of circulating microparticles (MPs are raised in various cardiovascular diseases. Their increased level in plasma is regarded as a biomarker of alteration in vascular function. The prominent MPs present in blood are endothelial microparticles (EMPs described as complex submicron (0.1 to 1.0 μm vesicles like structure, released in response to endothelium cell activation or apoptosis. EMPs possess both physiological and pathological effects and may promote oxidative stress and vascular inflammation. EMPs release is triggered by inducer like angiotensin II, lipopolysaccharide, and hydrogen peroxide leading to the progression of atherosclerosis. However, there are multiple physiological pathways for EMPs generation like NADPH oxidase derived endothelial ROS formation, Rho kinase pathway, and mitogen-activated protein kinases. Endothelial dysfunction is a key initiating event in atherosclerotic plaque formation. Atheroemboli, resulting from ruptured carotid plaques, is a major cause of stroke. Increasing evidence suggests that EMPs play an important role in the pathogenesis of cardiovascular disease, acting as a marker of damage, either exacerbating disease progression or triggering a repair response. In this regard, it has been suggested that EMPs have the potential to act as biomarkers of disease status. This review aims to provide updated information of EMPs in relation to atherosclerosis pathogenesis.

Interactions between endothelial progenitor cells (EPC) and titanium implant surfaces.

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Ziebart, Thomas; Schnell, Anne; Walter, Christian; Kämmerer, Peer W; Pabst, Andreas; Lehmann, Karl M; Ziebart, Johanna; Klein, Marc O; Al-Nawas, Bilal

2013-01-01

Endothelial cells play an important role in peri-implant angiogenesis during early bone formation. Therefore, interactions between endothelial progenitor cells (EPCs) and titanium dental implant surfaces are of crucial interest. The aim of our in vitro study was to investigate the reactions of EPCs in contact with different commercially available implant surfaces. EPCs from buffy coats were isolated by Ficoll density gradient separation. After cell differentiation, EPC were cultured for a period of 7 days on different titanium surfaces. The test surfaces varied in roughness and hydrophilicity: acid-etched (A), sand-blasted-blasted and acid-etched (SLA), hydrophilic A (modA), and hydrophilic SLA (modSLA). Plastic and fibronectin-coated plastic surfaces served as controls. Cell numbers and morphology were analyzed by confocal laser scanning microscopy. Secretion of vascular endothelial growth factor (VEGF)-A was measured by enzyme-linked immunosorbent assay and expressions of iNOS and eNOS were investigated by real-time polymerase chain reaction. Cell numbers were higher in the control groups compared to the cells of titanium surfaces. Initially, hydrophilic titanium surfaces (modA and modSLA) showed lower cell numbers than hydrophobic surfaces (A and SLA). After 7 days smoother surfaces (A and modA) showed increased cell numbers compared to rougher surfaces (SLA and modSLA). Cell morphology of A, modA, and control surfaces was characterized by a multitude of pseudopodia and planar cell soma architecture. SLA and modSLA promoted small and plump cell soma with little quantity of pseudopodia. The lowest VEGF level was measured on A, the highest on modSLA. The highest eNOS and iNOS expressions were found on modA surfaces. The results of this study demonstrate that biological behaviors of EPCs can be influenced by different surfaces. The modSLA surface promotes an undifferentiated phenotype of EPCs that has the ability to secrete growth factors in great quantities. In

MicroRNA 107 partly inhibits endothelial progenitor cells differentiation via HIF-1β.

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Shu Meng

Full Text Available Endothelial progenitor cells (EPCs play an important role in tissue repair after ischemic heart disease. In particular, the recovery of endothelial function is reliant on the ability and rate of EPCs differentiate into mature endothelial cells. The present study evaluated the effect of microRNA 107 (miR-107 on the mechanism of EPCs differentiation. EPCs were isolated from rats' bone marrow and miR-107 expression of EPCs in hypoxic and normoxic conditions were measured by real-time qualitative PCR. CD31 was analyzed by flow cytometry and eNOS was examined by real-time qualitative PCR and western blotting and these were used as markers of EPC differentiation. In order to reveal the mechanism, we used miR107 inhibitor and lentiviral vector expressing a short hairpin RNA (shRNA that targets miR-107 and hypoxia-inducible factor-1 β (HIF-1β to alter miR107 and HIF-1β expression. MiR-107 expression were increased in EPCs under hypoxic conditions. Up-regulation of miR-107 partly suppressed the EPCs differentiation induced in hypoxia, while down-regulation of miR-107 promoted EPC differentiation. HIF-1β was the target. This study indicated that miR-107 was up-regulated in hypoxia to prevent EPCs differentiation via its target HIF-1β. The physiological mechanisms of miR-107 must be evaluated if it is to be used as a potential anti-ischemia therapeutic regime.

Tissue engineering of bladder using vascular endothelial growth factor gene-modified endothelial progenitor cells.

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Chen, Bai-Song; Xie, Hua; Zhang, Sheng-Li; Geng, Hong-Quan; Zhou, Jun-Mei; Pan, Jun; Chen, Fang

2011-12-01

This study assessed the use of vascular endothelial growth factor (VEGF) gene-modified endothelial progenitor cells (EPCs) seeded onto bladder acellular matrix grafts (BAMGs), to enhance the blood supply in tissue-engineered bladders in a porcine model. Autologous porcine peripheral EPCs were isolated, cultured, expanded, characterized, and modified with the VEGF gene using an adenovirus vector. The expression of VEGF was examined using reverse transcriptase polymerase chain reaction (RT-PCR) and an enzyme-linked immunosorbent assay (ELISA). VEGF gene modified EPCs were seeded onto BAMG and cultured for 3 days before implantation into pigs for bladder tissue engineering. A partial bladder cystectomy was performed in 12 pigs. The experimental group (6 pigs) received VEGF gene-modified EPC-seeded BAMG. The control group (6 pigs) received BAMG without seeded EPCs. The resulting tissue-engineered bladders were subject to a general and histological analysis. Microvessel density (MVD) was assessed using immunohistochemistry. The ex vivo transfection efficiency of EPCs was greater than 60%-70% when concentrated adenovirus was used. The genetically modified cells expressed both VEGF and green fluorescent protein (GFP). Scanning electron microscopy (SEM) and Masson's trichrome staining of cross sections of the cultured cells seeded to BAMG showed cell attachment and proliferation on the surface of the BAMG. Histological examination revealed bladder regeneration in a time-dependent fashion. Significant increases in MVD were observed in the experimental group, in comparison with the control group. VEGF-modified EPCs significantly enhanced neovascularization, compared with BAMG alone. These results indicate that EPCs, combined with VEGF gene therapy, may be a suitable approach for increasing blood supply in the tissue engineering of bladders. Thus, a useful strategy to achieve a tissue-engineered bladder is indicated.

Circulating endothelial cells: a potential parameter of organ damage in sickle cell anemia?

NARCIS (Netherlands)

Strijbos, Michiel H.; Landburg, Precious P.; Nur, Erfan; Teerlink, Tom; Leebeek, Frank W. G.; Rijneveld, Anita W.; Biemond, Bart J.; Sleijfer, Stefan; Gratama, Jan W.; Duits, Ashley J.; Schnog, John-John B.

2009-01-01

Objective laboratory tools are needed to monitor developing organ damage in sickle cell disease (SCD). Circulating endothelial cells (CECs) are indicative of vascular injury. We determined whether elevated CEC can be detected in asymptomatic SCD with the CellSearch system and whether the CEC count

Shexiang Baoxin pills promotes angiogenesis in myocardial infarction rats via up-regulation of 20-HETE-mediated endothelial progenitor cells mobilization.

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Huang, Feifei; Liu, Yang; Yang, Xia; Che, Di; Qiu, Kaifeng; Hammock, Bruce D; Wang, Jingfeng; Wang, Mong-Heng; Chen, Jie; Huang, Hui

2017-08-01

Therapeutic angiogenesis is a pivotal strategy for ischemic heart disease. The aim of the present study was to determine the effect and molecular mechanism of Shexiang Baoxin pills, a widely-used traditional Chinese medicine for ischemic heart disease, on angiogenesis in a rat model of myocardial infarction (MI). We used the occlusion of left anterior descending coronary artery of Sprague-Dawley rats as a model of MI. The MI rats were treated with distilled water, Shexiang Baoxin pills, or Shexiang Baoxin pills + HET0016 (a selective blocker of the biosynthesis of 20-hydroxyeicosatetraenoic acid (20-HETE) at 10 mg/kg/day), respectively. Sham-operated rats were used as controls. Treatment with Shexiang Baoxin pills increases the level of serum 20-HETE in MI rats, which can be suppressed by HET0016 treatment. Shexiang Baoxin pills shows cardio-protective effects on MI rats, including improving cardiac function, decreasing infarction area, and promoting angiogenesis in peri-infarct area. The protective effects of Shexiang Baoxin pills are partly inhibited by HET0016. Furthermore, Shexiang Baoxin pills enhances the number of circulating endothelial progenitor cells (EPCs) and the expression of the vascular endothelial growth factor (VEGF), based on immunohistochemical analysis, in peri-infarct area of MI rats, which is partly suppressed by HET0016. Shexiang Baoxin pills may partially participate in angiogenesis in MI rats. The protective mechanism of Shexiang Baoxin pills may be mediated via up-regulation of 20-HETE, which promotes EPCs mobilization and VEGF expression. Copyright © 2017 Elsevier B.V. All rights reserved.

Circulating CD34-positive cells, glomerular filtration rate and triglycerides in relation to hypertension.

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Shimizu, Yuji; Sato, Shimpei; Koyamatsu, Jun; Yamanashi, Hirotomo; Nagayoshi, Mako; Kadota, Koichiro; Maeda, Takahiro

2015-11-01

Serum triglycerides have been reported to be independently associated with the development of chronic kidney disease (CKD), which is known to play a role in vascular disturbance. On the other hand, circulating CD34-positve cells, including endothelial progenitor cells, are reported to contribute to vascular repair. However, no studies have reported on the correlation between triglycerides and the number of CD34-positive cells. Since hypertension is well known factor for vascular impairment, the degree of correlation between serum triglycerides and circulating CD34-positve cells should account for hypertension status. We conducted a cross-sectional study of 274 elderly Japanese men aged ≥ 60 years (range 60-79 years) undergoing general health checkups. Multiple linear regression analysis of non-hypertensive subjects adjusting for classical cardiovascular risk factors showed that although triglyceride levels (1SD increments; 64 mg/dL) did not significantly correlate with glomerular filtration rate (GFR) (β = -2.06, p = 0.163), a significant positive correlation was seen between triglycerides and the number of circulating CD34-positive cells (β = 0.50, p = 0.004). In hypertensive subjects, a significant inverse correlation between triglycerides and GFR was observed (β = -2.66, p = 0.035), whereas no significant correlation between triglycerides and the number of circulating CD34-positive cells was noted (β = -0.004, p = 0.974). Since endothelial progenitor cells (CD34-positive cells) have been reported to contribute to vascular repair, our results indicate that in non-hypertensive subjects, triglycerides may stimulate an increase in circulating CD34-positive cells (vascular repair) by inducing vascular disturbance. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Surface modification of a polyhedral oligomeric silsesquioxane poly(carbonate-urea) urethane (POSS-PCU) nanocomposite polymer as a stent coating for enhanced capture of endothelial progenitor cells.

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Tan, Aaron; Farhatnia, Yasmin; Goh, Debbie; G, Natasha; de Mel, Achala; Lim, Jing; Teoh, Swee-Hin; Malkovskiy, Andrey V; Chawla, Reema; Rajadas, Jayakumar; Cousins, Brian G; Hamblin, Michael R; Alavijeh, Mohammad S; Seifalian, Alexander M

2013-12-01

An unmet need exists for the development of next-generation multifunctional nanocomposite materials for biomedical applications, particularly in the field of cardiovascular regenerative biology. Herein, we describe the preparation and characterization of a novel polyhedral oligomeric silsesquioxane poly(carbonate-urea) urethane (POSS-PCU) nanocomposite polymer with covalently attached anti-CD34 antibodies to enhance capture of circulating endothelial progenitor cells (EPC). This material may be used as a new coating for bare metal stents used after balloon angioplasty to improve re-endothelialization. Biophysical characterization techniques were used to assess POSS-PCU and its subsequent functionalization with anti-CD34 antibodies. Results indicated successful covalent attachment of anti-CD34 antibodies on the surface of POSS-PCU leading to an increased propensity for EPC capture, whilst maintaining in vitro biocompatibility and hemocompatibility. POSS-PCU has already been used in 3 first-in-man studies, as a bypass graft, lacrimal duct and a bioartificial trachea. We therefore postulate that its superior biocompatibility and unique biophysical properties would render it an ideal candidate for coating medical devices, with stents as a prime example. Taken together, anti-CD34 functionalized POSS-PCU could form the basis of a nano-inspired polymer platform for the next generation stent coatings.

Endothelial remodelling and intracellular calcium machinery.

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Moccia, F; Tanzi, F; Munaron, L

2014-05-01

Rather being an inert barrier between vessel lumen and surrounding tissues, vascular endothelium plays a key role in the maintenance of cardiovascular homeostasis. The de-endothelialization of blood vessels is regarded as the early event that results in the onset of severe vascular disorders, including atherosclerosis, acute myocardial infarction, brain stroke, and aortic aneurysm. Restoration of the endothelial lining may be accomplished by the activation of neighbouring endothelial cells (ECs) freed by contact inhibition and by circulating endothelial progenitor cells (EPCs). Intracellular Ca(2+) signalling is essential to promote wound healing: however, the molecular underpinnings of the Ca(2+) response to injury are yet to be fully elucidated. Similarly, the components of the Ca(2+) toolkit that drive EPC incorporation into denuded vessels are far from being fully elucidated. The present review will survey the current knowledge on the role of Ca(2+) signalling in endothelial repair and in EPC activation. We propose that endothelial regeneration might be boosted by intraluminal release of specific Ca(2+) channel agonists or by gene transfer strategies aiming to enhance the expression of the most suitable Ca(2+) channels at the wound site. In this view, connexin (Cx) channels/hemichannels and store-operated Ca(2+) entry (SOCE) stand amid the most proper routes to therapeutically induce the regrowth of denuded vessels. Cx stimulation might trigger the proliferative and migratory behaviour of ECs facing the lesion site, whereas activation of SOCE is likely to favour EPC homing to the wounded vessel.

Circulating Endothelial Cells in Patients with Heart Failure and Left Ventricular Dysfunction

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Martínez-Sales, Vicenta; Sánchez-Lázaro, Ignacio; Vila, Virtudes; Almenar, Luis; Contreras, Teresa; Reganon, Edelmiro

2011-01-01

Introduction and Aims: Acute and chronic heart failure may manifest different degrees of endothelial damage and angiogenesis. Circulating endothelial cells (CEC) have been identified as marker of vascular damage. The aim of our study was to evaluate the evolution of the CEC at different stages of patients with heart failure. We also investigated a potential correlation between CEC and markers of vascular damage and angiogenesis. Methods: We studied 32 heart failure patients at hospital admission (acute phase) and at revision after 3 months (stable phase) and 32 controls. Circulating markers of endothelial damage (CEC; von Willebrand factor, vWF and soluble E-selectin, sEsel) and angiogenesis (vascular endothelial growth factor, VEGF and thrombospondin-1) were quantified. Results: Levels of CEC, vWF, sEsel and VEGF are significantly higher in heart failure patients than in controls. Levels of CEC (36.9 ± 15.3 vs. 21.5 ± 10.0 cells/ml; p < 0.001), vWF (325 ± 101 vs. 231 ± 82%; p < 0.001) and VEGF (26.3 ± 15.2 vs. 21.9 ± 11.9 ng/ml; p < 0.001) are significantly higher in the acute phase than in the stable phase of heart failure. CEC levels correlate with vWF and VEGF. Results show than 100% of patients in acute phase and 37.5% in stable phase have levels of CEC higher than the 99th percentile of the distribution of controls (16 cells/ml). Therefore, increases in CEC represent a relative risk of 9.5 for heart failure patients suffering from acute phase. Conclusions: CEC, in addition to being elevated in heart failure, correlate with vWF levels, providing further support for CEC as markers of endothelial damage. Levels of CEC are associated with the acute phase of heart failure and could be used as a marker of the worsening in heart failure. PMID:21897001

Effect of prepro-calcitonin gene-related peptide-expressing endothelial progenitor cells on pulmonary hypertension.

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Zhao, Qiang; Liu, Zixiong; Wang, Zhe; Yang, Cheng; Liu, Jun; Lu, Jun

2007-08-01

Calcitonin gene-related peptide (CGRP) is a potent smooth muscle cell proliferation inhibitor and vasodilator. It is now believed that CGRP plays an important role in maintaining a low pulmonary vascular resistance. We evaluated the therapeutic effect of intravenously administered CGRP-expressing endothelial progenitor cells (EPCs) on left-to-right shunt-induced pulmonary hypertension in rats. Endothelial progenitor cells were obtained from cultured human peripheral blood mononuclear cells. The genetic sequence for CGRP was subcloned into cultured EPCs by human expression plasmid. Pulmonary hypertension was established in immunodeficient rats with an abdominal aorta to inferior vena cava shunt operation. The transfected EPCs were injected through the left jugular vein at 10 weeks after the shunt operation. Mean pulmonary artery pressure and total pulmonary vascular resistance were detected with right cardiac catheterization at 4 weeks. The distribution of EPCs in the lung tissue was examined with immunofluorescence technique. Histopathologic changes in the structure of the pulmonary arteries was observed with electron microscopy and subjected to computerized image analysis. The lungs of rats transplanted with CGRP-expressing EPCs demonstrated a decrease in both mean pulmonary artery pressure (17.64 +/- 0.79 versus 22.08 +/- 0.95 mm Hg; p = 0.018) and total pulmonary vascular resistance (1.26 +/- 0.07 versus 2.45 +/- 0.18 mm Hg x min/mL; p = 0.037) at 4 weeks. Immunofluorescence revealed that intravenously administered cells were incorporated into the pulmonary vasculature. Pulmonary vascular remodeling was remarkably attenuated with the administration of CGRP-expressing EPCs. The transplantation of CGRP-expressing EPCs may effectively attenuate established pulmonary hypertension and exert reversal effects on pulmonary vascular remodeling. Our findings suggest that the therapy based on the combination of both CGRP transfection and EPCs may be a potentially useful

Erythropoietin Attenuates Pulmonary Vascular Remodeling in Experimental Pulmonary Arterial Hypertension through Interplay between Endothelial Progenitor Cells and Heme Oxygenase

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van Loon, Rosa Laura E; Bartelds, Beatrijs; Wagener, Frank A D T G; Affara, Nada; Mohaupt, Saffloer; Wijnberg, Hans; Pennings, Sebastiaan W C; Takens, Janny; Berger, Rolf M F

2015-01-01

BACKGROUND: Pulmonary arterial hypertension (PAH) is a pulmonary vascular disease with a high mortality, characterized by typical angio-proliferative lesions. Erythropoietin (EPO) attenuates pulmonary vascular remodeling in PAH. We postulated that EPO acts through mobilization of endothelial progenitor cells (EPCs) and activation of the cytoprotective enzyme heme oxygenase-1 (HO-1). METHODS: Rats with flow-associated PAH, resembling pediatric PAH, were treated with HO-1 inducer EPO in the pre...

Erythropoietin Attenuates Pulmonary Vascular Remodeling in Experimental Pulmonary Arterial Hypertension through Interplay between Endothelial Progenitor Cells and Heme Oxygenase

OpenAIRE

van Loon, Rosa Laura E.; Bartelds, Beatrijs; Wagener, Frank A. D. T. G.; Affara, Nada; Mohaupt, Saffloer; Wijnberg, Hans; Pennings, Sebastiaan W. C.; Takens, Janny; Berger, Rolf M. F.

2015-01-01

Background Pulmonary arterial hypertension (PAH) is a pulmonary vascular disease with a high mortality, characterized by typical angio-proliferative lesions. Erythropoietin (EPO) attenuates pulmonary vascular remodeling in PAH. We postulated that EPO acts through mobilization of endothelial progenitor cells (EPCs) and activation of the cytoprotective enzyme heme oxygenase-1 (HO-1). Methods Rats with flow-associated PAH, resembling pediatric PAH, were treated with HO-1 inducer EPO i...

Insulin sensitizers prevent fine particulate matter-induced vascular insulin resistance and changes in endothelial progenitor cell homeostasis.

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Haberzettl, Petra; McCracken, James P; Bhatnagar, Aruni; Conklin, Daniel J

2016-06-01

Exposure to fine particular matter (PM2.5) increases the risk of developing cardiovascular disease and Type 2 diabetes. Because blood vessels are sensitive targets of air pollutant exposure, we examined the effects of concentrated ambient PM2.5 (CAP) on vascular insulin sensitivity and circulating levels of endothelial progenitor cells (EPCs), which reflect cardiovascular health. We found that CAP exposure for 9 days decreased insulin-stimulated Akt phosphorylation in the aorta of mice maintained on control diet. This change was accompanied by the induction of IL-1β and increases in the abundance of cleaved IL-18 and p10 subunit of Casp-1, consistent with the activation of the inflammasome pathway. CAP exposure also suppressed circulating levels of EPCs (Flk-1(+)/Sca-1(+) cells), while enhancing the bone marrow abundance of these cells. Although similar changes in vascular insulin signaling and EPC levels were observed in mice fed high-fat diet, CAP exposure did not exacerbate diet-induced changes in vascular insulin resistance or EPC homeostasis. Treatment with an insulin sensitizer, metformin or rosiglitazone, prevented CAP-induced vascular insulin resistance and NF-κB and inflammasome activation and restored peripheral blood and bone marrow EPC levels. These findings suggest that PM2.5 exposure induces diet-independent vascular insulin resistance and inflammation and prevents EPC mobilization, and that this EPC mobilization defect could be mediated by vascular insulin resistance. Impaired vascular insulin sensitivity may be an important mechanism underlying PM2.5-induced vascular injury, and pharmacological sensitization to insulin action could potentially prevent deficits in vascular repair and mitigate vascular inflammation due to exposure to elevated levels of ambient air pollution. Copyright © 2016 the American Physiological Society.

Hyperglycemia and oxidized-LDL exert a deleterious effect on endothelial progenitor cell migration in type 2 diabetes mellitus.

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Hamed, Saher; Brenner, Benjamin; Abassi, Zaid; Aharon, Anat; Daoud, Deeb; Roguin, Ariel

2010-09-01

Type 2 diabetes mellitus (DM) patients with coronary artery disease (CAD) have elevated plasma oxidized-LDL (OxLDL) levels and impaired neovascularization. Hyperglycemia and hyperlipidemia impair endothelial progenitor cell (EPC) migration, and endothelial nitric oxide (NO) bioavailability and NO synthase (NOS) activity are essential for EPC migration. Stromal-derived factor-1alpha (SDF1alpha) contributes to EPC mobilization and homing by stimulating the CXC receptor-4 (CXCR4) on the EPC plasmalemma to activate the Pi3K/Akt/eNOS signaling pathway. Therefore, we investigated the effect of high glucose (HG) and OxLDL on the migration and NO bioavailability of EPCs from healthy individuals, and then correlated the findings with those of EPCs from type 2 DM patients with and without CAD. EPCs from 15 healthy and 55 patients were exposed to HG, OxLDL, or both before evaluating EPC count, migration and NO production, and expression of CXCR4 and members of Pi3K/Akt/eNOS signaling cascade. Counts, migration, CXCR4 expression, and NO production were significantly reduced in EPCs from DM and CAD patients compared with that obtained in EPCs from healthy, and were further reduced in DM patients with CAD. The expression of CXCR4 and activation of Pi3K/Akt/eNOS signaling cascade were suppressed in OxLDL- and HG-treated EPCs, and this suppression was exacerbated when EPCs were treated simultaneously with HG and OxLDL. Hyperglycemia and elevated circulating OxLDL in DM patients with CAD severely impair EPC migration. These results suggest that the underlying mechanism for this impaired EPC migration is linked to the CXCR4/Pi3K/Akt/eNOS signaling pathway. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Rapid synthesis of water-dispersible superparamagnetic iron oxide nanoparticles by a microwave-assisted route for safe labeling of endothelial progenitor cells.

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Carenza, Elisa; Barceló, Verónica; Morancho, Anna; Montaner, Joan; Rosell, Anna; Roig, Anna

2014-08-01

We synthesize highly crystalline citrate-coated iron oxide superparamagnetic nanoparticles that are stable and readily dispersible in water by an extremely fast microwave-assisted route and investigate the uptake of magnetic nanoparticles by endothelial cells. Nanoparticles form large aggregates when added to complete endothelial cell medium. The size of the aggregates was controlled by adjusting the ionic strength of the medium. The internalization of nanoparticles into endothelial cells was then investigated by transmission electron microscopy, magnetometry and chemical analysis, together with cell viability assays. Interestingly, a sevenfold more efficient uptake was found for systems with larger nanoparticle aggregates, which also showed significantly higher magnetic resonance imaging effectiveness without compromising cell viability and functionality. We are thus presenting an example of a straightforward microwave synthesis of citrate-coated iron oxide nanoparticles for safe endothelial progenitor cell labeling and good magnetic resonance cell imaging with potential application for magnetic cell guidance and in vivo cell tracking. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Manipulating Endothelial Progenitor Cell Homing with Sphingosine-1-Phosphate for Terapeutic Angiogenesis

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Williams, Priscilla Anne

Ischemic vascular diseases are the main cause of mortality worldwide and yet current therapies only delay disease progression and improve quality of life without addressing the fundamental problem of tissue loss. Within the field of tissue engineering, therapeutic angiogenesis provides a promising approach to alternatively provide new blood vessel formation via spatiotemporally controlled delivery of proangiogenic agents. Sphingosine-1-phosphate (S1P), a bioactive lysophospholipid that is upregulated under ischemic conditions, has recently gained great enthusiasm as a potential mediator in neovascularization strategies given its essential roles in promoting both neovessel formation and stabilization, and cellular trafficking along highly regulated endogenous gradients. Herein, the governing hypothesis guiding this dissertation is that local biomaterial-controlled delivery of S1P may be used to enhance migration and recruitment of vascular progenitor cells for enhanced therapeutic angiogenesis within ischemic tissue. The initial work in this dissertation investigated the effect of hypoxia on the angiogenic response of both mature and progenitor endothelial cells to S1P stimulation in vitro. Outgrowth endothelial cells (OECs) were isolated from human umbilical cord blood to provide a clinically relevant source of vascular progenitor cells for the studies conducted within this dissertation. S1P stimulation promoted angiogenic activity of both ECs and OECs under both ambient and hypoxic (1%) oxygen tensions. Furthermore, dual therapy with the combination of S1P and vascular endothelial growth factor (VEGF) further enhanced cellular responses. Interestingly, hypoxia substantially augmented the functional response of OECs to S1P, resulting in 25-fold and 6.5-fold increases in directed migration and sprouting, respectively. Thus, these studies highlighted the potential for S1P as a therapeutic agent for treatment of ischemic diseases. An injectable biomaterial system

Functional convergence of Akt protein with VEGFR-1 in human endothelial progenitor cells exposed to sera from patient with type 2 diabetes mellitus.

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Hassanpour, Mehdi; Rezabakhsh, Aysa; Rahbarghazi, Reza; Nourazarian, Alireza; Nouri, Mohammad; Avci, Çığır Biray; Ghaderi, Shahrooz; Alidadyani, Neda; Bagca, Bakiye Goker; Bagheri, Hesam Saghaei

2017-11-01

Diabetes mellitus type 2 predisposes patients to various microvascular complications. In the current experiment, the potent role of diabetes mellitus was investigated on the content of VEGFR-1, -2, Tie-1 and -2, and Akt in human endothelial progenitor cells. The gene expression profile of mTOR and Hedgehog signaling pathways were measured by PCR array. The possible crosstalk between RTKs, mTOR and Hedgehog signaling was also studied by bioinformatic analysis. Endothelial progenitor cells were incubated with serum from normal and diabetic for 7days. Compared to non-treated cells, diabetic serum-induced cell apoptosis (~2-fold) and prohibited cell migration toward bFGF (p1). ELISA analysis showed that diabetes exposed cells had increased abundance of Tie-1, -2 and VEGFR-2 and reduced amount of VEGFR-1 (p1) in diabetic cells. Western blotting showed a marked reduction in the protein level of Akt after cells exposure to serum from diabetic subjects (p1). PCR array revealed a significant stimulation of both mTOR and Hedgehog signaling pathways in diabetic cells (p1, -2 and Tie-2, but not Tie-1, are master regulators of angiogenesis. There is a crosstalk between RTKs and mTOR signaling by involving P62, GABARAPL1, and HTT genes. It seems that physical interaction and co-expression of Akt decreased the level of VEGFR-1 in diabetic cells. Regarding data from the present experiment, diabetic serum contributed to uncontrolled induction of both mTOR and Hedgehog signaling in endothelial progenitor cells. Diabetes mellitus induces mTOR pathway by involving receptor tyrosine kinases while Hedgehog stimulation is independent of these receptors. Copyright © 2017 Elsevier Inc. All rights reserved.

Red wine consumption improves in vitro migration of endothelial progenitor cells in young, healthy individuals.

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Hamed, Saher; Alshiek, Jonia; Aharon, Anat; Brenner, Benjamin; Roguin, Ariel

2010-07-01

Endothelial progenitor cells (EPCs) contribute to the maintenance of vascular endothelial function. The moderate consumption of red wine provides cardiovascular protection. We investigated the underlying molecular mechanism of EPC migration in young, healthy individuals who drank red wine. Fourteen healthy volunteers consumed 250 mL red wine daily for 21 consecutive days. Vascular endothelial function, plasma stromal cell-derived factor 1alpha (SDF1alpha) concentrations, and the number, migration, and nitric oxide production of EPCs were determined before and after the daily consumption of red wine. EPCs were glucose stressed to study the effect of red wine on EPC migration, proliferation, and senescence and to study the expressions of CXC chemokine receptor 4 (CXCR4) and members of the Pi3K/Akt/eNOS (phosphatidylinositol 3-kinase/protein kinase B/endothelial nitric oxide synthase) signaling pathway by Western blotting. Daily red wine consumption for 21 consecutive days significantly enhanced vascular endothelial function. Although plasma SDF1alpha concentrations were unchanged, EPC count and migration were significantly increased after this 21-d consumption period. Red wine increased the migration, proliferation, CXCR4 expression, and activity of the Pi3K/Akt/eNOS signaling pathway and decreased the extent of apoptosis in glucose-stressed EPCs. The results of the present study indicate that red wine exerts its effect through the up-regulation of CXCR4 expression and activation of the SDF1alpha/CXCR4/Pi3K/Akt/eNOS signaling pathway, which results in increased EPC migration and proliferation and decreased extent of apoptosis. Our findings suggest that these effects could be linked to the mechanism of cardiovascular protection that is associated with the regular consumption of red wine.

Endothelial progenitors encapsulated in bioartificial niches are insulated from systemic cytotoxicity and are angiogenesis competent.

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Ratliff, B B; Ghaly, T; Brudnicki, P; Yasuda, K; Rajdev, M; Bank, M; Mares, J; Hatzopoulos, A K; Goligorsky, M S

2010-07-01

Intrinsic stem cells (SC) participate in tissue remodeling and regeneration in various diseases and following toxic insults. Failure of tissue regeneration is in part attributed to lack of SC protection from toxic stress of noxious stimuli, thus prompting intense research efforts to develop strategies for SC protection and functional preservation for in vivo delivery. One strategy is creation of artificial SC niches in an attempt to mimic the requirements of endogenous SC niches by generating scaffolds with properties of extracellular matrix. Here, we investigated the use of hyaluronic acid (HA) hydrogels as an artificial SC niche and examined regenerative capabilities of encapsulated embryonic endothelial progenitor cells (eEPC) in three different in vivo models. Hydrogel-encapsulated eEPC demonstrated improved resistance to toxic insult (adriamycin) in vitro, thus prompting in vivo studies. Implantation of HA hydrogels containing eEPC to mice with adriamycin nephropathy or renal ischemia resulted in eEPC mobilization to injured kidneys (and to a lesser extent to the spleen) and improvement of renal function, which was equal or superior to adoptively transferred EPC by intravenous infusion. In mice with hindlimb ischemia, EPC encapsulated in HA hydrogels dramatically accelerated the recovery of collateral circulation with the efficacy superior to intravenous infusion of EPC. In conclusion, HA hydrogels protect eEPC against adriamycin cytotoxicity and implantation of eEPC encapsulated in HA hydrogels supports renal regeneration in ischemic and cytotoxic (adriamycin) nephropathy and neovascularization of ischemic hindlimb, thus establishing their functional competence and superior capabilities to deliver stem cells stored in and released from this bioartificial niche.

Nitric oxide and superoxide dismutase modulate endothelial progenitor cell function in type 2 diabetes mellitus.

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Hamed, Saher; Brenner, Benjamin; Aharon, Anat; Daoud, Deeb; Roguin, Ariel

2009-10-30

The function of endothelial progenitor cells (EPCs), which are key cells in vascular repair, is impaired in diabetes mellitus. Nitric oxide (NO) and reactive oxygen species can regulate EPC functions. EPCs tolerate oxidative stress by upregulating superoxide dismutase (SOD), the enzyme that neutralizes superoxide anion (O2-). Therefore, we investigated the roles of NO and SOD in glucose-stressed EPCs. The functions of circulating EPCs from patients with type 2 diabetes were compared to those from healthy individuals. Healthy EPCs were glucose-stressed, and then treated with insulin and/or SOD. We assessed O2- generation, NO production, SOD activity, and their ability to form colonies. EPCs from diabetic patients generated more O2-, had higher NAD(P)H oxidase and SOD activity, but lower NO bioavailability, and expressed higher mRNA and protein levels of p22-phox, and manganese SOD and copper/zinc SOD than those from the healthy individuals. Plasma glucose and HbA1c levels in the diabetic patients were correlated negatively with the NO production from their EPCs. SOD treatment of glucose-stressed EPCs attenuated O2- generation, restored NO production, and partially restored their ability to form colonies. Insulin treatment of glucose-stressed EPCs increased NO production, but did not change O2- generation and their ability to form colonies. However, their ability to produce NO and to form colonies was fully restored after combined SOD and insulin treatment. Our data provide evidence that SOD may play an essential role in EPCs, and emphasize the important role of antioxidant therapy in type 2 diabetic patients.

MicroRNA-126 Priming Enhances Functions of Endothelial Progenitor Cells under Physiological and Hypoxic Conditions and Their Therapeutic Efficacy in Cerebral Ischemic Damage

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Qunwen Pan

2018-01-01

Full Text Available Endothelial progenitor cells (EPCs have shown the potential for treating ischemic stroke (IS, while microRNA-126 (miR-126 is reported to have beneficial effects on endothelial function and angiogenesis. In this study, we investigated the effects of miR-126 overexpression on EPCs and explore the efficacy of miR-126-primed EPCs (EPCmiR-126 in treating IS. The effects of miR-126 overexpression on EPC proliferation, migratory, tube formation capacity, reactive oxygen species (ROS production, and nitric oxide (NO generation were determined. In in vivo study, the effects of EPCmiR-126 on the cerebral blood flow (CBF, neurological deficit score (NDS, infarct volume, cerebral microvascular density (cMVD, and angiogenesis were determined. Moreover, the levels of circulating EPCs (cEPCs and their contained miR-126 were measured. We found (1 miR-126 overexpression promoted the proliferation, migration, and tube formation abilities of EPCs; decreased ROS; and increased NO production of EPCs via activation of PI3K/Akt/eNOS pathway; (2 EPCmiR-126 was more effective than EPCs in attenuating infarct volume and NDS and enhancing cMVD, CBF, and angiogenesis; and (3 infusion of EPCmiR-126 increased the number and the level of miR-126 in cEPCs. Our data indicate that miR-126 overexpression enhanced the function of EPCs in vitro and in vivo.

Atrial Natriuretic Peptide Accelerates Human Endothelial Progenitor Cell-Stimulated Cutaneous Wound Healing and Angiogenesis.

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Lee, Tae Wook; Kwon, Yang Woo; Park, Gyu Tae; Do, Eun Kyoung; Yoon, Jung Won; Kim, Seung-Chul; Ko, Hyun-Chang; Kim, Moon-Bum; Kim, Jae Ho

2018-05-26

Atrial natriuretic peptide (ANP) is a powerful vasodilating peptide secreted by cardiac muscle cells, and endothelial progenitor cells (EPCs) have been reported to stimulate cutaneous wound healing by mediating angiogenesis. To determine whether ANP can promote the EPC-mediated repair of injured tissues, we examined the effects of ANP on the angiogenic properties of EPCs and on cutaneous wound healing. In vitro, ANP treatment enhanced the migration, proliferation, and endothelial tube-forming abilities of EPCs. Furthermore, small interfering RNA-mediated silencing of natriuretic peptide receptor-1, which is a receptor for ANP, abrogated ANP-induced migration, tube formation, and proliferation of EPCs. In a murine cutaneous wound model, administration of either ANP or EPCs had no significant effect on cutaneous wound healing or angiogenesis in vivo, whereas the co-administration of ANP and EPCs synergistically potentiated wound healing and angiogenesis. In addition, ANP promoted the survival and incorporation of transplanted EPCs into newly formed blood vessels in wounds. These results suggest ANP accelerates EPC-mediated cutaneous wound healing by promoting the angiogenic properties and survival of transplanted EPCs. This article is protected by copyright. All rights reserved. © 2018 by the Wound Healing Society.

Effects of angiopoietin-1 on inflammatory injury in endothelial progenitor cells and blood vessels.

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Wang, Yi-Qing; Song, Jing-Jin; Han, Xiao; Liu, Yi-Ye; Wang, Xi-Huang; Li, Zhi-Ming; Tzeng, Chi-Meng

2014-01-01

Endothelial progenitor cells (EPCs) and angiopoietin-1 (Ang-1) play important roles in vasculogenesis and angiogenesis, respectively. Thus, targeting both aspects of cardiovascular tissue regeneration may offer promising therapeutic options for cardiovascular disorders. To this end, we constructed a lentiviral vector (pNL) with the Ang-1 gene and transfected EPCs with it (Ang-1-EPCs) to investigate vasculogenesis in both cellular and animal models. Compared to controls, intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) increased significantly in both untreated EPCs and in the pNL vector group. After Ang-1 transcription, ICAM-1 and VCAM-1 decreased considerably in those treatment groups. Ang-1-modified EPCs alleviated inflammatory responses induced by tumor-necrosis factor-α (TNF-α) in vitro. Moreover, Ang-1-EPC implantation inhibited neointimal hyperplasia after balloon catheter injury in rats, dramatically diminishing the intimal-media (I/M) ratio and decreasing the neointimal area. Proliferating cell nuclear antigen expression in the Ang-1-EPC group was lower than the EPC non-treatment group as well, suggesting that Ang-1-EPC improved cell survival during inflammation and promoted endothelialization in damaged blood vessels.

Effect of increased exercise in school children on physical fitness and endothelial progenitor cells: a prospective randomized trial.

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Walther, Claudia; Gaede, Luise; Adams, Volker; Gelbrich, Götz; Leichtle, Alexander; Erbs, Sandra; Sonnabend, Melanie; Fikenzer, Kati; Körner, Antje; Kiess, Wieland; Bruegel, Mathias; Thiery, Joachim; Schuler, Gerhard

2009-12-01

The aim of this prospective, randomized study was to examine whether additional school exercise lessons would result in improved peak oxygen uptake (primary end point) and body mass index-standard deviation score, motor and coordinative abilities, circulating progenitor cells, and high-density lipoprotein cholesterol (major secondary end points). Seven sixth-grade classes (182 children, aged 11.1+/-0.7 years) were randomized to an intervention group (4 classes with 109 students) with daily school exercise lessons for 1 year and a control group (3 classes with 73 students) with regular school sports twice weekly. The significant effects of intervention estimated from ANCOVA adjusted for intraclass correlation were the following: increase of peak o(2) (3.7 mL/kg per minute; 95% confidence interval, 0.3 to 7.2) and increase of circulating progenitor cells evaluated by flow cytometry (97 cells per 1 x 10(6) leukocytes; 95% confidence interval, 13 to 181). No significant difference was seen for body mass index-standard deviation score (-0.08; 95% confidence interval, -0.28 to 0.13); however, there was a trend to reduction of the prevalence of overweight and obese children in the intervention group (from 12.8% to 7.3%). No treatment effect was seen for motor and coordinative abilities (4; 95% confidence interval, -1 to 8) and high-density lipoprotein cholesterol (0.03 mmol/L; 95% confidence interval, -0.08 to 0.14). Regular physical activity by means of daily school exercise lessons has a significant positive effect on physical fitness (o(2)max). Furthermore, the number of circulating progenitor cells can be increased, and there is a positive trend in body mass index-standard deviation score reduction and motor ability improvement. Therefore, we conclude that primary prevention by means of increasing physical activity should start in childhood. URL: http://www.clinicaltrials.gov. Identifier: NCT00176371.

Endothelial progenitor cells regenerate infracted myocardium with neovascularisation development.

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Abd El Aziz, M T; Abd El Nabi, E A; Abd El Hamid, M; Sabry, D; Atta, H M; Rahed, L A; Shamaa, A; Mahfouz, S; Taha, F M; Elrefaay, S; Gharib, D M; Elsetohy, Khaled A

2015-03-01

We achieved possibility of isolation, characterization human umbilical cord blood endothelial progenitor cells (EPCs), examination potency of EPCs to form new blood vessels and differentiation into cardiomyoctes in canines with acute myocardial infarction (AMI). EPCs were separated and cultured from umbilical cord blood. Their phenotypes were confirmed by uptake of double stains dioctadecyl tetramethylindocarbocyanine-labeled acetylated LDL and FITC-labeled Ulex europaeus agglutinin 1 (DILDL-UEA-1). EPCs of cord blood were counted. Human VEGFR-2 and eNOS from the cultured EPCs were assessed by qPCR. Human EPCs was transplanted intramyocardially in canines with AMI. ECG and cardiac enzymes (CK-MB and Troponin I) were measured to assess severity of cellular damage. Histopathology was done to assess neovascularisation. Immunostaining was done to detect EPCs transdifferentiation into cardiomyocytes in peri-infarct cardiac tissue. qPCR for human genes (hVEGFR-2, and eNOS) was done to assess homing and angiogenic function of transplanted EPCs. Cultured human cord blood exhibited an increased number of EPCs and significant high expression of hVEGFR-2 and eNOS genes in the culture cells. Histopathology showed increased neovascularization and immunostaining showed presence of EPCs newly differentiated into cardiomyocyte-like cells. Our findings suggested that hEPCs can mediate angiogenesis and differentiate into cardiomyoctes in canines with AMI.

Influence of sex on the number of circulating endothelial microparticles and microRNA expression in middle-aged adults.

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Bammert, Tyler D; Hijmans, Jamie G; Kavlich, Philip J; Lincenberg, Grace M; Reiakvam, Whitney R; Fay, Ryan T; Greiner, Jared J; Stauffer, Brian L; DeSouza, Christopher A

2017-08-01

What is the central question of this study? Are there sex-related differences in the number of circulating endothelial microparticles (EMPs) and microparticle microRNA expression in middle-aged adult humans? What is the main finding and its importance? Although the numbers of circulating endothelial microparticles do not differ between middle-aged men and women, there are sex-related differences in the expression of miR-125a in activation-derived EMPs and miR-34a in apoptosis-derived EMPs. Differences in circulating endothelial microparticle microRNA content may provide new insight into the sex-related disparity in the risk and prevalence of vascular disease in middle-aged adults. The aims of this study were to determine: (i) whether circulating concentrations of endothelial microparticles (EMPs) differ in middle-aged men compared with women; and (ii) whether there are sex-related differences in microRNA expression in EMPs. Peripheral blood was collected from 30 sedentary adults: 15 men (56 ± 6 years old) and 15 women (56 ± 5 years old). Endothelial microparticles were defined by markers of activation (CD62e + ) or apoptosis (CD31 + /CD42b - ) by flow cytometry. Expression of microRNA (miR-34a, 92a, 125a and 126) in activation- and apoptosis-derived EMPs was measured by RT-PCR. Circulating activation- (33 ± 31 versus 39 ± 35 microparticles μl -1 ) and apoptosis-derived EMPs (49 ± 54 versus 42 ± 43 microparticles μl -1 ) were not significantly different between men and women. Expression of miR-125a (2.23 ± 2.01 versus 6.95 ± 3.99 a.u.) was lower (∼215%; P < 0.05) in activation-derived EMPs, whereas expression of miR-34a (1.17 ± 1.43 versus 0.38 ± 0.35 a.u.) was higher (∼210%; P < 0.05) in apoptosis-derived EMPs from men compared with women. Expression of microRNA in circulating EMPs may provide new insight into sex-related differences in cardiovascular disease. © 2017 The Authors. Experimental Physiology © 2017 The

Impact of ADMA, endothelial progenitor cells and traditional cardiovascular risk factors on pulse wave velocity among prediabetic individuals

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Protopsaltis Ioannis

2012-11-01

Full Text Available Abstract Background Central arterial stiffness represents a well-established predictor of cardiovascular disease. Decreased circulating endothelial progenitor cells (EPCs, increased asymmetric dimethyl-arginine (ADMA levels, traditional cardiovascular risk factors and insulin resistance have all been associated with increased arterial stiffness. The correlations of novel and traditional cardiovascular risk factors with central arterial stiffness in prediabetic individuals were investigated in the present study. Methods The study population consisted of 53 prediabetic individuals. Individuals were divided into groups of isolated impaired fasting glucose (IFG, isolated impaired glucose tolerance (IGT and combined IGT-IFG. Age, sex, family history of diabetes, smoking history, body mass index (BMI, waist to hip ratio (WHR, waist circumference (WC, blood pressure, lipid profile, levels of high sensitive C-reactive protein (hsCRP, glomerular filtration rate (GFR, and history of antihypertensive or statin therapy were obtained from all participants. Insulin resistance was evaluated using the Homeostatic Model Assessment (HOMA-IR. Carotid -femoral pulse wave velocity was used as an index of arterial stiffness. Circulating EPC count and ADMA serum levels were also determined. Results Among studied individuals 30 (56.6% subjects were diagnosed with isolated IFG, 9 (17% with isolated IGT (17% and 14 with combined IFG-IGT (26.4%. In univariate analysis age, mean blood pressure, fasting glucose, total cholesterol, LDL cholesterol, and ADMA levels positively correlated with pulse-wave velocity while exercise and GFR correlated negatively. EPC count did not correlate with PWV. In multivariate stepwise regression analysis PWV correlated independently and positively with LDL-Cholesterol (low density lipoprotein and ADMA levels and negatively with exercise. Conclusions Elevated ADMA and LDL-C levels are strongly associated with increased arterial stiffness among

Increased expression of microRNA-221 inhibits PAK1 in endothelial progenitor cells and impairs its function via c-Raf/MEK/ERK pathway

International Nuclear Information System (INIS)

Zhang, Xiaoping; Mao, Haian; Chen, Jin-yuan; Wen, Shengjun; Li, Dan; Ye, Meng; Lv, Zhongwei

2013-01-01

Highlights: ► MicroRNA-221 is upregulated in the endothelial progenitor cells of atherosclerosis patients. ► PAK1 is a direct target of microRNA-221. ► MicroRNA-221 inhibits EPCs proliferation through c-Raf/MEK/ERK pathway. -- Abstract: Coronary artery disease (CAD) is associated with high mortality and occurs via endothelial injury. Endothelial progenitor cells (EPCs) restore the integrity of the endothelium and protect it from atherosclerosis. In this study, we compared the expression of microRNAs (miRNAs) in EPCs in atherosclerosis patients and normal controls. We found that miR-221 expression was significantly up-regulated in patients compared with controls. We predicted and identified p21/Cdc42/Rac1-activated kinase 1 (PAK1) as a novel target of miR-221 in EPCs. We also demonstrated that miR-221 targeted a putative binding site in the 3′UTR of PAK1, and absence of this site was inversely associated with miR-221 expression in EPCs. We confirmed this relationship using a luciferase reporter assay. Furthermore, overexpression of miR-221 in EPCs significantly decreased EPC proliferation, in accordance with the inhibitory effects induced by decreased PAK1. Overall, these findings demonstrate that miR-221 affects the MEK/ERK pathway by targeting PAK1 to inhibit the proliferation of EPCs

Butein Inhibits Angiogenesis of Human Endothelial Progenitor Cells via the Translation Dependent Signaling Pathway

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Ching-Hu Chung

2013-01-01

Full Text Available Compelling evidence indicates that bone marrow-derived endothelial progenitor cells (EPCs can contribute to postnatal neovascularization and tumor angiogenesis. EPCs have been shown to play a “catalytic” role in metastatic progression by mediating the angiogenic switch. Understanding the pharmacological functions and molecular targets of natural products is critical for drug development. Butein, a natural chalcone derivative, has been reported to exert potent anticancer activity. However, the antiangiogenic activity of butein has not been addressed. In this study, we found that butein inhibited serum- and vascular endothelial growth factor- (VEGF- induced cell proliferation, migration, and tube formation of human EPCs in a concentration dependent manner without cytotoxic effect. Furthermore, butein markedly abrogated VEGF-induced vessels sprouting from aortic rings and suppressed microvessel formation in the Matrigel implant assay in vivo. In addition, butein concentration-dependently repressed the phosphorylation of Akt, mTOR, and the major downstream effectors, p70S6K, 4E-BP1, and eIF4E in EPCs. Taken together, our results demonstrate for the first time that butein exhibits the antiangiogenic effect both in vitro and in vivo by targeting the translational machinery. Butein is a promising angiogenesis inhibitor with the potential for treatment of cancer and other angiogenesis-related diseases.

Nitric oxide and superoxide dismutase modulate endothelial progenitor cell function in type 2 diabetes mellitus

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Brenner Benjamin

2009-10-01

Full Text Available Abstract Background The function of endothelial progenitor cells (EPCs, which are key cells in vascular repair, is impaired in diabetes mellitus. Nitric oxide (NO and reactive oxygen species can regulate EPC functions. EPCs tolerate oxidative stress by upregulating superoxide dismutase (SOD, the enzyme that neutralizes superoxide anion (O2-. Therefore, we investigated the roles of NO and SOD in glucose-stressed EPCs. Methods The functions of circulating EPCs from patients with type 2 diabetes were compared to those from healthy individuals. Healthy EPCs were glucose-stressed, and then treated with insulin and/or SOD. We assessed O2- generation, NO production, SOD activity, and their ability to form colonies. Results EPCs from diabetic patients generated more O2-, had higher NAD(PH oxidase and SOD activity, but lower NO bioavailability, and expressed higher mRNA and protein levels of p22-phox, and manganese SOD and copper/zinc SOD than those from the healthy individuals. Plasma glucose and HbA1c levels in the diabetic patients were correlated negatively with the NO production from their EPCs. SOD treatment of glucose-stressed EPCs attenuated O2- generation, restored NO production, and partially restored their ability to form colonies. Insulin treatment of glucose-stressed EPCs increased NO production, but did not change O2- generation and their ability to form colonies. However, their ability to produce NO and to form colonies was fully restored after combined SOD and insulin treatment. Conclusion Our data provide evidence that SOD may play an essential role in EPCs, and emphasize the important role of antioxidant therapy in type 2 diabetic patients.

Paracrine effects of bone marrow-derived endothelial progenitor cells: cyclooxygenase-2/prostacyclin pathway in pulmonary arterial hypertension.

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Dong-Mei Jiang

Full Text Available BACKGROUND: Endothelial dysfunction is the pathophysiological characteristic of pulmonary arterial hypertension (PAH. Some paracrine factors secreted by bone marrow-derived endothelial progenitor cells (BMEPCs have the potential to strengthen endothelial integrity and function. This study investigated whether BMEPCs have the therapeutic potential to improve monocrotaline (MCT-induced PAH via producing vasoprotective substances in a paracrine fashion. METHODS AND RESULTS: Bone marrow-derived mononuclear cells were cultured for 7 days to yield BMEPCs. 24 hours or 3 weeks after exposure to BMEPCs in vitro or in vivo, the vascular reactivity, cyclooxygenase-2 (COX-2 expression, prostacyclin (PGI2 and cAMP release in isolated pulmonary arteries were examined respectively. Treatment with BMEPCs could improve the relaxation of pulmonary arteries in MCT-induced PAH and BMEPCs were grafted into the pulmonary bed. The COX-2/prostacyclin synthase (PGIS and its progenies PGI2/cAMP were found to be significantly increased in BMEPCs treated pulmonary arteries, and this action was reversed by a selective COX-2 inhibitor, NS398. Moreover, the same effect was also observed in conditioned medium obtained from BMEPCs culture. CONCLUSIONS: Implantation of BMEPCs effectively ameliorates MCT-induced PAH. Factors secreted in a paracrine fashion from BMEPCs promote vasoprotection by increasing the release of PGI2 and level of cAMP.

Endothelial progenitor cells regenerate infracted myocardium with neovascularisation development

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M.T. Abd El Aziz

2015-03-01

Full Text Available We achieved possibility of isolation, characterization human umbilical cord blood endothelial progenitor cells (EPCs, examination potency of EPCs to form new blood vessels and differentiation into cardiomyoctes in canines with acute myocardial infarction (AMI. EPCs were separated and cultured from umbilical cord blood. Their phenotypes were confirmed by uptake of double stains dioctadecyl tetramethylindocarbocyanine-labeled acetylated LDL and FITC-labeled Ulex europaeus agglutinin 1 (DILDL-UEA-1. EPCs of cord blood were counted. Human VEGFR-2 and eNOS from the cultured EPCs were assessed by qPCR. Human EPCs was transplanted intramyocardially in canines with AMI. ECG and cardiac enzymes (CK-MB and Troponin I were measured to assess severity of cellular damage. Histopathology was done to assess neovascularisation. Immunostaining was done to detect EPCs transdifferentiation into cardiomyocytes in peri-infarct cardiac tissue. qPCR for human genes (hVEGFR-2, and eNOS was done to assess homing and angiogenic function of transplanted EPCs. Cultured human cord blood exhibited an increased number of EPCs and significant high expression of hVEGFR-2 and eNOS genes in the culture cells. Histopathology showed increased neovascularization and immunostaining showed presence of EPCs newly differentiated into cardiomyocyte-like cells. Our findings suggested that hEPCs can mediate angiogenesis and differentiate into cardiomyoctes in canines with AMI.

Bone engineering in dog mandible: Coculturing mesenchymal stem cells with endothelial progenitor cells in a composite scaffold containing vascular endothelial growth factor.

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Khojasteh, Arash; Fahimipour, Farahnaz; Jafarian, Mohammad; Sharifi, Davoud; Jahangir, Shahrbanoo; Khayyatan, Fahimeh; Baghaban Eslaminejad, Mohamadreza

2017-10-01

We sought to assess the effects of coculturing mesenchymal stem cells (MSCs) and endothelial progenitor cells (EPCs) in the repair of dog mandible bone defects. The cells were delivered in β-tricalcium phosphate scaffolds coated with poly lactic co-glycolic acid microspheres that gradually release vascular endothelial growth factor (VEGF). The complete scaffold and five partial scaffolds were implanted in bilateral mandibular body defects in eight beagles. The scaffolds were examined histologically and morphometrically 8 weeks after implantation. Histologic staining of the decalcified scaffolds demonstrated that bone formation was greatest in the VEGF/MSC scaffold (63.42 ± 1.67), followed by the VEGF/MSC/EPC (47.8 ± 1.87) and MSC/EPC (45.21 ± 1.6) scaffolds, the MSC scaffold (34.59 ± 1.49), the VEGF scaffold (20.03 ± 1.29), and the untreated scaffold (7.24 ± 0.08). Hence, the rate of new bone regeneration was highest in scaffolds containing MSC, either mixed with EPC or incorporating VEGF. Adding both EPC and VEGF with the MSC was not necessary. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1767-1777, 2017. © 2016 Wiley Periodicals, Inc.

VEGF 165 Gene Therapy for Patients with Refractory Angina: Mobilization of Endothelial Progenitor Cells

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Rodrigues, Clarissa G.; Plentz, Rodrigo D.M.; Dipp, Thiago; Salles, Felipe B.; Giusti, Imarilde I.; Sant'Anna, Roberto T.; Eibel, Bruna; Nesralla, Ivo A.; Markoski, Melissa; Beyer, Nance N.; Kalil, Renato A. K.

2013-01-01

Vascular endothelial growth factor (VEGF) induces mobilization of endothelial progenitor cells (EPCs) with the capacity for proliferation and differentiation into mature endothelial cells, thus contributing to the angiogenic process. We sought to assess the behavior of EPCs in patients with ischemic heart disease and refractory angina who received an intramyocardial injections of 2000 µg of VEGF 165 as the sole therapy. The study was a subanalysis of a clinical trial. Patients with advanced ischemic heart disease and refractory angina were assessed for eligibility. Inclusion criteria were as follows: signs and symptoms of angina and/or heart failure despite maximum medical treatment and a myocardial ischemic area of at least 5% as assessed by single-photon emission computed tomography (SPECT). Exclusion criteria were as follows: age > 65 years, left ventricular ejection fraction < 25%, and a diagnosis of cancer. Patients whose EPC levels were assessed were included. The intervention was 2000 µg of VEGF 165 plasmid injected into the ischemic myocardium. The frequency of CD34+/KDR+ cells was analyzed by flow cytometry before and 3, 9, and 27 days after the intervention. A total of 9 patients were included, 8 males, mean age 59.4 years, mean left ventricular ejection fraction of 59.3% and predominant class III angina. The number of EPCs on day 3 was significantly higher than that at baseline (p = 0.03); however, that on days 9 th and 27 th was comparable to that at baseline. We identified a transient mobilization of EPCs, which peaked on the 3th day after VEGF 165 gene therapy in patients with refractory angina and returned to near baseline levels on 9 th and 27 th days

Smooth muscle cells in atherosclerosis originate from the local vessel wall and not circulating progenitor cells in ApoE knockout mice

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Bentzon, Jacob Fog; Weile, Charlotte; Sondergaard, Claus S

2006-01-01

Recent studies of bone marrow (BM)-transplanted apoE knockout (apoE-/-) mice have concluded that a substantial fraction of smooth muscle cells (SMCs) in atherosclerosis arise from circulating progenitor cells of hematopoietic origin. This pathway, however, remains controversial. In the present st...

Effect of colorectal cancer on the number of normal stem cells circulating in peripheral blood.

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Marlicz, Wojciech; Sielatycka, Katarzyna; Serwin, Karol; Kubis, Ewa; Tkacz, Marta; Głuszko, Rafał; Białek, Andrzej; Starzyńska, Teresa; Ratajczak, Mariusz Z

2016-12-01

Bone marrow (BM) residing stem cells are mobilized from their BM niches into peripheral blood (PB) in several pathological situations including tissue organ injury and systemic inflammation. We recently reported that the number of BM-derived stem cells (SCs) increases in patients with pancreatic and stomach cancer. Accordingly, we observed higher numbers of circulating very small embryonic/epiblast‑like stem cells (VSELs) and mesenchymal stem cells (MSCs) that were associated with the activation of pro-mobilizing complement cascade and an elevated level of sphingosine-1 phosphate (S1P) in PB plasma. We wondered if a similar correlation occurs in patients with colorectal cancer (CRC). A total of 46 patients were enrolled in this study: 17 with CRC, 18 with benign colonic adenomas (BCA) and 11 healthy individuals. By employing fluorescence-activated cell sorting (FACS) we evaluated the number of BM-derived SCs circulating in PB: i) CD34+/Lin-/CD45- and CD133-/Lin-/CD45- VSELs; ii) CD45-/CD105+/CD90+/CD29+ MSCs; iii) CD45-/CD34+/CD133+/KDR+ endothelial progenitor cells (EPCs); and iv) CD133+/Lin-/CD45+ or CD34+/Lin-/CD45+ cells enriched for hematopoietic stem/progenitor cells (HSPCs). In parallel, we measured in the PB parameters regulating the egress of SCs from BM into PB. In contrast to pancreatic and gastric cancer patients, CRC subjects presented neither an increase in the number of circulating SCs nor the activation of pro-mobilizing factors such as complement, coagulation and fibrinolytic cascade, circulating stromal derived factor 1 (SDF‑1), vascular endothelial growth factor (VEGF) and intestinal permeability marker (zonulin). In conclusion, mobilization of SCs in cancer patients depends on the type of malignancy and its ability to activate pro-mobilization cascades.

Enhanced expression of Stim, Orai, and TRPC transcripts and proteins in endothelial progenitor cells isolated from patients with primary myelofibrosis.

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Silvia Dragoni

Full Text Available BACKGROUND: An increase in the frequency of circulating endothelial colony forming cells (ECFCs, the only subset of endothelial progenitor cells (EPCs truly belonging to the endothelial phenotype, occurs in patients affected by primary myelofibrosis (PMF. Herein, they might contribute to the enhanced neovascularisation of fibrotic bone marrow and spleen. Store-operated Ca2+ entry (SOCE activated by the depletion of the inositol-1,4,5-trisphosphate (InsP3-sensitive Ca2+ store drives proliferation in ECFCs isolated from both healthy donors (N-ECFCs and subjects suffering from renal cellular carcinoma (RCC-ECFCs. SOCE is up-regulated in RCC-ECFCs due to the over-expression of its underlying molecular components, namely Stim1, Orai1, and TRPC1. METHODOLOGY/PRINCIPAL FINDINGS: We utilized Ca2+ imaging, real-time polymerase chain reaction, western blot analysis and functional assays to evaluate molecular structure and the functional role of SOCE in ECFCs derived from PMF patients (PMF-ECFCs. SOCE, induced by either pharmacological (i.e. cyclopiazonic acid or CPA or physiological (i.e. ATP stimulation, was significantly higher in PMF-ECFCs. ATP-induced SOCE was inhibited upon blockade of the phospholipase C/InsP3 signalling pathway with U73111 and 2-APB. The higher amplitude of SOCE was associated to the over-expression of the transcripts encoding for Stim2, Orai2-3, and TRPC1. Conversely, immunoblotting revealed that Stim2 levels remained constant as compared to N-ECFCs, while Stim1, Orai1, Orai3, TRPC1 and TRPC4 proteins were over-expressed in PMF-ECFCs. ATP-induced SOCE was inhibited by BTP-2 and low micromolar La3+ and Gd3+, while CPA-elicited SOCE was insensitive to Gd3+. Finally, BTP-2 and La3+ weakly blocked PMF-ECFC proliferation, while Gd3+ was ineffective. CONCLUSIONS: Two distinct signalling pathways mediate SOCE in PMF-ECFCs; one is activated by passive store depletion and is Gd3+-resistant, while the other one is regulated by the InsP3

Endothelial progenitor cells display clonal restriction in multiple myeloma

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Braunstein, Marc; Özçelik, Tayfun; Bağişlar, Sevgi; Vakil, Varsha; Smith, Eric LP; Dai, Kezhi; Akyerli, Cemaliye B; Batuman, Olcay A

2006-01-01

In multiple myeloma (MM), increased neoangiogenesis contributes to tumor growth and disease progression. Increased levels of endothelial progenitor cells (EPCs) contribute to neoangiogenesis in MM, and, importantly, covary with disease activity and response to treatment. In order to understand the mechanisms responsible for increased EPC levels and neoangiogenic function in MM, we investigated whether these cells were clonal by determining X-chromosome inactivation (XCI) patterns in female patients by a human androgen receptor assay (HUMARA). In addition, EPCs and bone marrow cells were studied for the presence of clonotypic immunoglobulin heavy-chain (IGH) gene rearrangement, which indicates clonality in B cells; thus, its presence in EPCs would indicate a close genetic link between tumor cells in MM and endothelial cells that provide tumor neovascularization. A total of twenty-three consecutive patients who had not received chemotherapy were studied. Screening in 18 patients found that 11 displayed allelic AR in peripheral blood mononuclear cells, and these patients were further studied for XCI patterns in EPCs and hair root cells by HUMARA. In 2 patients whose EPCs were clonal by HUMARA, and in an additional 5 new patients, EPCs were studied for IGH gene rearrangement using PCR with family-specific primers for IGH variable genes (V H ). In 11 patients, analysis of EPCs by HUMARA revealed significant skewing (≥ 77% expression of a single allele) in 64% (n = 7). In 4 of these patients, XCI skewing was extreme (≥ 90% expression of a single allele). In contrast, XCI in hair root cells was random. Furthermore, PCR amplification with V H primers resulted in amplification of the same product in EPCs and bone marrow cells in 71% (n = 5) of 7 patients, while no IGH rearrangement was found in EPCs from healthy controls. In addition, in patients with XCI skewing in EPCs, advanced age was associated with poorer clinical status, unlike patients whose EPCs had random XCI

Acute myocardial infarction is associated with endothelial glycocalyx and cell damage and a parallel increase in circulating catecholamines

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Ostrowski, Sisse R; Pedersen, Sune H; Jensen, Jan S

2013-01-01

INTRODUCTION: Excessive sympathoadrenal activation in critical illness contributes directly to organ damage, and high concentrations of catecholamines damage the vascular endothelium. This study investigated associations between potential drivers of sympathoadrenal activation, circulating...... catecholamines and biomarkers of endothelial damage and outcome in ST segment elevation myocardial infarction (STEMI)-patients, hypothesizing that the catecholamine surge would reflect shock degree and correlate with biomarkers of endothelial damage. METHODS: This was a prospective study of 678 consecutive STEMI...

Towards the therapeutic use of vascular smooth muscle progenitor cells.

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Merkulova-Rainon, Tatyana; Broquères-You, Dong; Kubis, Nathalie; Silvestre, Jean-Sébastien; Lévy, Bernard I

2012-07-15

Recent advances in the development of alternative proangiogenic and revascularization processes, including recombinant protein delivery, gene therapy, and cell therapy, hold the promise of greater efficacy in the management of cardiovascular disease in the coming years. In particular, vascular progenitor cell-based strategies have emerged as an efficient treatment approach to promote vessel formation and repair and to improve tissue perfusion. During the past decade, considerable progress has been achieved in understanding therapeutic properties of endothelial progenitor cells, while the therapeutic potential of vascular smooth muscle progenitor cells (SMPC) has only recently been explored; the number of the circulating SMPC being correlated with cardiovascular health. Several endogenous SMPC populations with varying phenotypes have been identified and characterized in the peripheral blood, bone marrow, and vascular wall. While the phenotypic entity of vascular SMPC is not fully defined and remains an evolving area of research, SMPC are increasingly recognized to play a special role in cardiovascular biology. In this review, we describe the current approaches used to define vascular SMPC. We further summarize the data on phenotype and functional properties of SMPC from various sources in adults. Finally, we discuss the role of SMPC in cardiovascular disease, including the contribution of SMPC to intimal proliferation, angiogenesis, and atherosclerotic plaque instability as well as the benefits resulting from the therapeutic use of SMPC.

VEGF 165 Gene Therapy for Patients with Refractory Angina: Mobilization of Endothelial Progenitor Cells

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Rodrigues, Clarissa G. [Instituto de Cardiologia/Fundação Universitária de Cardiologia - Programa de Pós Graduação em Ciências da Saúde: Cardiologia, Porto Alegre, RS (Brazil); Duke University Medical Center, Durham, North Carolina (United States); Plentz, Rodrigo D.M. [Instituto de Cardiologia/Fundação Universitária de Cardiologia - Programa de Pós Graduação em Ciências da Saúde: Cardiologia, Porto Alegre, RS (Brazil); Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, RS (Brazil); Dipp, Thiago [Instituto de Cardiologia/Fundação Universitária de Cardiologia - Programa de Pós Graduação em Ciências da Saúde: Cardiologia, Porto Alegre, RS (Brazil); Salles, Felipe B. [Instituto de Cardiologia/Fundação Universitária de Cardiologia - Programa de Pós Graduação em Ciências da Saúde: Cardiologia, Porto Alegre, RS (Brazil); Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, RS (Brazil); Giusti, Imarilde I.; Sant' Anna, Roberto T.; Eibel, Bruna; Nesralla, Ivo A.; Markoski, Melissa [Instituto de Cardiologia/Fundação Universitária de Cardiologia - Programa de Pós Graduação em Ciências da Saúde: Cardiologia, Porto Alegre, RS (Brazil); Beyer, Nance N. [Instituto de Cardiologia/Fundação Universitária de Cardiologia - Programa de Pós Graduação em Ciências da Saúde: Cardiologia, Porto Alegre, RS (Brazil); Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil); Kalil, Renato A. K., E-mail: kalil.pesquisa@gmail.com [Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, RS (Brazil)

2013-08-15

Vascular endothelial growth factor (VEGF) induces mobilization of endothelial progenitor cells (EPCs) with the capacity for proliferation and differentiation into mature endothelial cells, thus contributing to the angiogenic process. We sought to assess the behavior of EPCs in patients with ischemic heart disease and refractory angina who received an intramyocardial injections of 2000 µg of VEGF 165 as the sole therapy. The study was a subanalysis of a clinical trial. Patients with advanced ischemic heart disease and refractory angina were assessed for eligibility. Inclusion criteria were as follows: signs and symptoms of angina and/or heart failure despite maximum medical treatment and a myocardial ischemic area of at least 5% as assessed by single-photon emission computed tomography (SPECT). Exclusion criteria were as follows: age > 65 years, left ventricular ejection fraction < 25%, and a diagnosis of cancer. Patients whose EPC levels were assessed were included. The intervention was 2000 µg of VEGF 165 plasmid injected into the ischemic myocardium. The frequency of CD34+/KDR+ cells was analyzed by flow cytometry before and 3, 9, and 27 days after the intervention. A total of 9 patients were included, 8 males, mean age 59.4 years, mean left ventricular ejection fraction of 59.3% and predominant class III angina. The number of EPCs on day 3 was significantly higher than that at baseline (p = 0.03); however, that on days 9{sup th} and 27{sup th} was comparable to that at baseline. We identified a transient mobilization of EPCs, which peaked on the 3th day after VEGF 165 gene therapy in patients with refractory angina and returned to near baseline levels on 9{sup th} and 27{sup th}days.

Sustained apnea induces endothelial activation.

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Eichhorn, Lars; Dolscheid-Pommerich, Ramona; Erdfelder, Felix; Ayub, Muhammad Ajmal; Schmitz, Theresa; Werner, Nikos; Jansen, Felix

2017-09-01

Apnea diving has gained worldwide popularity, even though the pathophysiological consequences of this challenging sport on the human body are poorly investigated and understood. This study aims to assess the influence of sustained apnea in healthy volunteers on circulating microparticles (MPs) and microRNAs (miRs), which are established biomarkers reflecting vascular function. Short intermittent hypoxia due to voluntary breath-holding affects circulating levels of endothelial cell-derived MPs (EMPs) and endothelial cell-derived miRs. Under dry laboratory conditions, 10 trained apneic divers performed maximal breath-hold. Venous blood samples were taken, once before and at 4 defined points in time after apnea. Samples were analyzed for circulating EMPs and endothelial miRs. Average apnea time was 329 seconds (±103), and SpO 2 at the end of apnea was 79% (±12). Apnea was associated with a time-dependent increase of circulating endothelial cell-derived EMPs and endothelial miRs. Levels of circulating EMPs in the bloodstream reached a peak 4 hours after the apnea period and returned to baseline levels after 24 hours. Circulating miR-126 levels were elevated at all time points after a single voluntary maximal apnea, whereas miR-26 levels were elevated significantly only after 30 minutes and 4 hours. Also miR-21 and miR-92 levels increased, but did not reach the level of significance. Even a single maximal breath-hold induces acute endothelial activation and should be performed with great caution by subjects with preexisting vascular diseases. Voluntary apnea might be used as a model to simulate changes in endothelial function caused by hypoxia in humans. © 2017 Wiley Periodicals, Inc.

Valsartan reduces AT1-AA-induced apoptosis through suppression oxidative stress mediated ER stress in endothelial progenitor cells.

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Wang, Z-C; Qi, J; Liu, L-M; Li, J; Xu, H-Y; Liang, B; Li, B

2017-03-01

Valsartan has been reported to have the function of treating hypertension and improving the prognosis of patients. Many studies indicated that valsartan can also increase angiotensin II, andosterone and plasma renin activity (PRA). Autoantibodies against the angiotensin II type 1 receptor (AT1-AA) have been showed to increase reactive oxygen species (ROS) and calcium (Ca2+) and result in apoptosis in vascular smooth muscle cells. In this study, we attempted to explore the effect of valsartan on AT1-AA-induced apoptosis in endothelial progenitor cells. Endothelial progenitor cells (EPCs) were cultured. The cytotoxicity was determined by MTT assay. EPCs apoptosis was determined by DAPI staining and flow cytometry. Reactive oxygen species, intracellular calcium concentration and calpain activity were measured using Fluostar Omega Spectrofluorimeter. The expression of p-ERK, p-eIF-2a, CHOP, Bcl-2 and caspase-3 were detected by Western blot. MTT assays showed valsartan significantly inhibited AT1-AA- induced decline of the viability of EPCs. DAPI staining and flow cytometry results indicated valsartan inhibited AT1-AA-induced decline of the viability of EPCs via inhibiting AT1-AA-induced apoptosis. Furthermore, the increasing of reactive oxygen species, intracellular calcium and calpain activity induced by AT1-AA in EPCs were also recovered after pre-treated with valsartan. Meanwhile, the upregulation of p-ERK, p-eIF-2a and CHOP, downregulation of Bcl-2, and activation of Caspase-3 caused by AT1-AA were reversed after pre-incubated with valsartan. Valsartan could inhibit AT1-AA-induced apoptosis through inhibiting oxidative stress mediated ER stress in EPCs.

In vivo endothelization of tubular vascular grafts through in situ recruitment of endothelial and endothelial progenitor cells by RGD-fused mussel adhesive proteins

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Kang, Tae-Yun; Lee, Jung Ho; Kang, Jo-A; Rhie, Jong-Won; Kim, Bum Jin; Cha, Hyung Joon; Hong, Jung Min; Kim, Byoung Soo; Cho, Dong-Woo

2015-01-01

The use of tissue mimics in vivo, including patterned vascular networks, is expected to facilitate the regeneration of functional tissues and organs with large volumes. Maintaining patency of channels in contact with blood is an important issue in the development of a functional vascular network. Endothelium is the only known completely non-thrombogenic material; however, results from treatments to induce endothelialization are inconclusive. The present study was designed to evaluate the clinical applicability of in situ recruitment of endothelial cells/endothelial progenitor cells (EC/EPC) and pre-endothelization using a recombinant mussel adhesive protein fused with arginine–glycine–aspartic acid peptide (MAP-RGD) coating in a model of vascular graft implantation. Microporous polycaprolactone (PCL) scaffolds were fabricated with salt leaching methods and their surfaces were modified with collagen and MAP-RGD. We then evaluated their anti-thrombogenicity with an in vitro hemocompatibility assessment and a 4-week implantation in the rabbit carotid artery. We observed that MAP-RGD coating reduced the possibility of early in vivo graft failure and enhanced re-endothelization by in situ recruitment of EC/EPC (patency rate: 2/3), while endothelization prior to implantation aggravated the formation of thrombosis and/or IH (patency rate: 0/3). The results demonstrated that in situ recruitment of EC/EPC by MAP-RGD could be a promising strategy for vascular applications. In addition, it rules out several issues associated with pre-endothelization, such as cell source, purity, functional modulation and contamination. Further evaluation of long term performance and angiogenesis from the luminal surface may lead to the clinical use of MAP-RGD for tubular vascular grafts and regeneration of large-volume tissues with functional vascular networks. (paper)

Manufacture of endothelial colony-forming progenitor cells from steady-state peripheral blood leukapheresis using pooled human platelet lysate.

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Siegel, Georg; Fleck, Erika; Elser, Stefanie; Hermanutz-Klein, Ursula; Waidmann, Marc; Northoff, Hinnak; Seifried, Erhard; Schäfer, Richard

2018-05-01

Endothelial colony-forming progenitor cells (ECFCs) are promising candidates for cell therapies. However, ECFC translation to the clinic requires optimized isolation and manufacture technologies according to good manufacturing practice (GMP). ECFCs were manufactured from steady-state peripheral blood (PB) leukapheresis (11 donors), using GMP-compliant technologies including pooled human platelet (PLT) lysate, and compared to human umbilical cord endothelial cells, human aortic endothelial cells, and human cerebral microvascular endothelial cells. Specific variables assessed were growth kinetics, phenotype, trophic factors production, stimulation of tube formation, and Dil-AcLDL uptake. ECFCs could be isolated from PB leukapheresis units with mean processed volume of 5411 mL and mean white blood cell (WBC) concentration factor of 8.74. The mean frequency was 1.44 × 10 -8 ECFCs per WBC, corresponding to a mean of 177.8 ECFCs per apheresis unit. Expandable for up to 12 cumulative population doublings, calculated projection showed that approximately 730 × 10 3 ECFCs could be manufactured from 1 apheresis unit. ECFCs produced epidermal growth factor, hepatocyte growth factor, vascular endothelial growth factor (VEGF)-A, PLT-derived growth factor-B, interleukin-8, and monocyte chemoattractant protein-1, featured high potential for capillary-like tubes formation, and showed no telomerase activity. They were characterized by CD29, CD31, CD44, CD105, CD117, CD133, CD144, CD146, and VEGF-R2 expression, with the most common subpopulation CD34+CD117-CD133-. Compared to controls, ECFCs featured greater Dil-AcLDL uptake and higher expression of CD29, CD31, CD34, CD44, CD144, and VEGF-R2. Here we show that isolation of ECFCs with proangiogenic profile from steady-state PB leukapheresis is feasible, marking a first step toward ECFC product manufacture according to GMP. © 2018 AABB.

Black Tea Increases Circulating Endothelial Progenitor Cells and Improves Flow Mediated Dilatation Counteracting Deleterious Effects from a Fat Load in Hypertensive Patients: A Randomized Controlled Study

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Grassi, Davide; Draijer, Richard; Schalkwijk, Casper; Desideri, Giovambattista; D’Angeli, Anatolia; Francavilla, Sandro; Mulder, Theo; Ferri, Claudio

2016-01-01

(1) Background: Endothelial dysfunction predicts cardiovascular events. Circulating angiogenic cells (CACs) maintain and repair the endothelium regulating its function. Tea flavonoids reduce cardiovascular risk. We investigated the effects of black tea on the number of CACs and on flow-mediated dilation (FMD) before and after an oral fat in hypertensives; (2) Methods: In a randomized, double-blind, controlled, cross-over study, 19 patients were assigned to black tea (150 mg polyphenols) or a placebo twice a day for eight days. Measurements were obtained in a fasted state and after consuming whipping cream, and FMD was measured at baseline and after consumption of the products; (3) Results: Compared with the placebo, black tea ingestion increased functionally active CACs (36 ± 22 vs. 56 ± 21 cells per high-power field; p = 0.006) and FMD (5.0% ± 0.3% vs. 6.6% ± 0.3%, p FMD 1, 2, 3, and 4 h after consumption, with maximal response 2 h after intake (p FMD, while tea consumption counteracted FMD impairment (p < 0.0001); (4) Conclusions: We demonstrated the vascular protective properties of black tea by increasing the number of CACs and preventing endothelial dysfunction induced by acute oral fat load in hypertensive patients. Considering that tea is the most consumed beverage after water, our findings are of clinical relevance and interest. PMID:27854314

Effects of Clopidogrel Therapy on Oxidative Stress, Inflammation, Vascular Function and Progenitor Cells in Stable Coronary Artery Disease

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Ramadan, Ronnie; Dhawan, Saurabh S.; Syed, Hamid; Pohlel, F. Khan; Binongo, Jose Nilo G.; Ghazzal, Ziyad B.; Quyyumi, Arshed A.

2014-01-01

Background Traditional cardiovascular risk factors lead to endothelial injury and activation of leucocytes and platelets that initiate and propagate atherosclerosis. We proposed that clopidogrel therapy in patients with stable CAD imparts a pleiotropic effect that extends beyond anti-platelet aggregation to other athero-protective processes. Methods Forty-one subjects were randomized in a double-blind, placebo-controlled crossover study to either clopidogrel 75 mg daily or placebo for 6-weeks, and then transitioned immediately to the other treatment for an additional 6 weeks. We assessed 1) endothelial function as flow-mediated dilation of the brachial artery, 2) arterial stiffness and central augmentation index using applanation tonometry, 3) vascular function as fingertip reactive hyperemia index, 4) inflammation by measuring plasma CD40 ligand and serum high-sensitivity c-reactive protein levels, 5) oxidative stress by measuring plasma aminothiols, and 6) circulating progenitor cells, at baseline and at the end of each 6-week treatment period. Results Clopidogrel therapy resulted in a significant reduction in soluble CD40 ligand (p=0.03), a pro-thrombotic and pro-inflammatory molecule derived mainly from activated platelets. However, clopidogrel therapy had no effect on endothelial function, arterial stiffness, inflammatory and oxidative stress markers, or progenitor cells. Conclusions Our findings suggest a solitary anti-platelet effect of clopidogrel therapy in patients with stable CAD, with no effect on other sub-clinical markers of cardiovascular disease risk. PMID:24336012

Endothelial Progenitor Cell Fraction Contained in Bone Marrow-Derived Mesenchymal Stem Cell Populations Impairs Osteogenic Differentiation

Directory of Open Access Journals (Sweden)

Fabian Duttenhoefer

2015-01-01

Full Text Available In bone tissue engineering (TE endothelial cell-osteoblast cocultures are known to induce synergies of cell differentiation and activity. Bone marrow mononucleated cells (BMCs are a rich source of mesenchymal stem cells (MSCs able to develop an osteogenic phenotype. Endothelial progenitor cells (EPCs are also present within BMC. In this study we investigate the effect of EPCs present in the BMC population on MSCs osteogenic differentiation. Human BMCs were isolated and separated into two populations. The MSC population was selected through plastic adhesion capacity. EPCs (CD34+ and CD133+ were removed from the BMC population and the resulting population was named depleted MSCs. Both populations were cultured over 28 days in osteogenic medium (Dex+ or medium containing platelet lysate (PL. MSC population grew faster than depleted MSCs in both media, and PL containing medium accelerated the proliferation for both populations. Cell differentiation was much higher in Dex+ medium in both cases. Real-time RT-PCR revealed upregulation of osteogenic marker genes in depleted MSCs. Higher values of ALP activity and matrix mineralization analyses confirmed these results. Our study advocates that absence of EPCs in the MSC population enables higher osteogenic gene expression and matrix mineralization and therefore may lead to advanced bone neoformation necessary for TE constructs.

Mobilization of Circulating Vascular Progenitors in Cancer Patients Receiving External Beam Radiation in Response to Tissue Injury

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Allan, David S.; Morgan, Scott C.; Birch, Paul E.; Yang, Lin; Halpenny, Michael J.; Gunanayagam, Angelo; Li Yuhua; Eapen, Libni

2009-01-01

Purpose: Endothelial-like vascular progenitor cells (VPCs) are associated with the repair of ischemic tissue injury in several clinical settings. Because the endothelium is a principal target of radiation injury, VPCs may be important in limiting toxicity associated with radiotherapy (RT) in patients with cancer. Methods and Materials: We studied 30 patients undergoing RT for skin cancer (n = 5), head-and-neck cancer (n = 15), and prostate cancer (n = 10) prospectively, representing a wide range of irradiated mucosal volumes. Vascular progenitor cell levels were enumerated from peripheral blood at baseline, midway through RT, at the end of treatment, and 4 weeks after radiation. Acute toxicity was graded at each time point by use of the National Cancer Institute's Common Toxicity Criteria, version 3.0. Results: Significant increases in the proportion of CD34 + /CD133 + VPCs were observed after completion of RT, from 0.012% at baseline to 0.048% (p = 0.029), and the increase in this subpopulation was most marked in patients with Grade 2 peak toxicity or greater after RT (p = 0.034). Similarly, CD34 + /vascular endothelial growth factor receptor 2-positive VPCs were increased after the completion of radiation therapy in comparison to baseline (from 0.014% to 0.027%, p = 0.043), and there was a trend toward greater mobilization in patients with more significant toxicity (p = 0.08). The mobilization of CD34 + hematopoietic stem cells did not increase after treatment (p = 0.58), and there was no relationship with toxicity. Conclusions: We suggest that VPCs may play an important role in reducing radiation-induced tissue damage. Interventions that increase baseline VPC levels or enhance their mobilization and recruitment in response to RT may prove useful in facilitating more rapid and complete tissue healing.

Schlafen 1 inhibits the proliferation and tube formation of endothelial progenitor cells.

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Chun-yan Kuang

Full Text Available Endothelial progenitor cells (EPCs are the major source of cells that restore the endothelium during reendothelialization. This study was designed to investigate whether Schlafen 1 (Slfn1 has an effect on the proliferation and tube formation of EPCs in vivo. Slfn1 was expressed in rat EPCs. The overexpression of Slfn1 suppressed the proliferation and tube formation of EPCs; conversely, the knockdown of Slfn1 by shRNA promoted the proliferation and tube formation of EPCs. Furthermore, when Slfn1 was overexpressed, the EPCs were arrested in the G1 phase of the cell cycle. In contrast, when Slfn1 was knocked down, the EPCs progressed into the S phase of the cell cycle. Additionally, the overexpression of Slfn1 decreased the expression of Cyclin D1, whereas the knockdown of Slfn1 increased the expression of Cyclin D1; these findings suggest that Cyclin D1 is downstream of Slfn1 in Slfn1-mediated EPC proliferation. Taken together, these results indicate a key role for Slfn1 in the regulation of EPC biological behavior, which may provide a new target for the use of EPCs during reendothelialization.

Impact of an endothelial progenitor cell capturing stent on coronary microvascular function: comparison with drug-eluting stents.

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Choi, Woong Gil; Kim, Soo Hyun; Yoon, Hyung Seok; Lee, Eun Joo; Kim, Dong Woon

2015-01-01

Although drug-eluting stents (DESs) effectively reduce restenosis following percutaneous coronary intervention (PCI), they also delay re-endothelialization and impair microvascular function, resulting in adverse clinical outcomes. Endothelial progenitor cell (EPC) capturing stents, by providing a functional endothelial layer on the stent, have beneficial effects on microvascular function. However, data on coronary microvascular function in patients with EPC stents versus DESs are lacking. Seventy-four patients who previously underwent PCI were enrolled in this study. Microvascular function was evaluated 6 months after PCI based on the index of microvascular resistance (IMR) and the coronary flow reserve (CFR). IMR was calculated as the ratio of the mean distal coronary pressure at maximal hyperemia to the inverse of the hyperemic mean transit time (hTmn). The CFR was calculated by dividing the hTmn by the baseline mean transit time. Twenty-one patients (age, 67.2 ± 9.6 years; male:female, 15:6) with an EPC stent and 53 patients (age, 61.5 ± 14.7 years; male:female, 40:13) with second-generation DESs were included in the study. There were no significant differences in the baseline clinical and angiographic characteristics of the two groups. Angiography performed 6 months postoperatively did not show significant differences in their CFR values. However, patients with the EPC stent had a significantly lower IMR than patients with second-generation DESs (median, 25.5 [interquartile range, 12.85 to 28.18] vs. 29.0 [interquartile range, 15.42 to 39.23]; p = 0.043). Microvascular dysfunction was significantly improved after 6 months in patients with EPC stents compared to those with DESs. The complete re-endothelialization achieved with the EPC stent may provide clinical benefits over DESs, especially in patients with microvascular dysfunction.

Optimized multiparametric flow cytometric analysis of circulating endothelial cells and their subpopulations in peripheral blood of patients with solid tumors: a technical analysis.

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Zhou, Fangbin; Zhou, Yaying; Yang, Ming; Wen, Jinli; Dong, Jun; Tan, Wenyong

2018-01-01

Circulating endothelial cells (CECs) and their subpopulations could be potential novel biomarkers for various malignancies. However, reliable enumerable methods are warranted to further improve their clinical utility. This study aimed to optimize a flow cytometric method (FCM) assay for CECs and subpopulations in peripheral blood for patients with solid cancers. An FCM assay was used to detect and identify CECs. A panel of 60 blood samples, including 44 metastatic cancer patients and 16 healthy controls, were used in this study. Some key issues of CEC enumeration, including sample material and anticoagulant selection, optimal titration of antibodies, lysis/wash procedures of blood sample preparation, conditions of sample storage, sufficient cell events to enhance the signal, fluorescence-minus-one controls instead of isotype controls to reduce background noise, optimal selection of cell surface markers, and evaluating the reproducibility of our method, were integrated and investigated. Wilcoxon and Mann-Whitney U tests were used to determine statistically significant differences. In this validation study, we refined a five-color FCM method to detect CECs and their subpopulations in peripheral blood of patients with solid tumors. Several key technical issues regarding preanalytical elements, FCM data acquisition, and analysis were addressed. Furthermore, we clinically validated the utility of our method. The baseline levels of mature CECs, endothelial progenitor cells, and activated CECs were higher in cancer patients than healthy subjects ( P technical issues found in previously published assays and validated the reproducibility and sensitivity of our proposed method. Future work is required to explore the potential of our optimized method in clinical oncologic applications.

Notch-RBP-J signaling regulates the mobilization and function of endothelial progenitor cells by dynamic modulation of CXCR4 expression in mice.

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Lin Wang

Full Text Available Bone marrow (BM-derived endothelial progenitor cells (EPC have therapeutic potentials in promoting tissue regeneration, but how these cells are modulated in vivo has been elusive. Here, we report that RBP-J, the critical transcription factor mediating Notch signaling, modulates EPC through CXCR4. In a mouse partial hepatectomy (PHx model, RBP-J deficient EPC showed attenuated capacities of homing and facilitating liver regeneration. In resting mice, the conditional deletion of RBP-J led to a decrease of BM EPC, with a concomitant increase of EPC in the peripheral blood. This was accompanied by a down-regulation of CXCR4 on EPC in BM, although CXCR4 expression on EPC in the circulation was up-regulated in the absence of RBP-J. PHx in RBP-J deficient mice induced stronger EPC mobilization. In vitro, RBP-J deficient EPC showed lowered capacities of adhering, migrating, and forming vessel-like structures in three-dimensional cultures. Over-expression of CXCR4 could at least rescue the defects in vessel formation by the RBP-J deficient EPC. These data suggested that the RBP-J-mediated Notch signaling regulated EPC mobilization and function, at least partially through dynamic modulation of CXCR4 expression. Our findings not only provide new insights into the regulation of EPC, but also have implications for clinical therapies using EPC in diseases.

Mobilization of endothelial progenitor cells after endovascular interventions in patients with type 2 diabetes mellitus

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Marina Sergeevna Michurova

2014-12-01

Full Text Available Aim. To investigate the mobilisation of endothelial progenitor cells (EPC in patients with type 2 diabetes mellitus (T2DM after endovascular interventions for coronary and peripheral arteries. Materials and Methods. The levels of EPC in peripheral blood were determined by flow cytometry in 42 patients prior to endovascular intervention and 2?4 days after surgery. EPC were defined as CD34+ VEGFR2+ CD45- and CD34+ CD133+CD45- cells. Twenty-three patients with T2DM were included in group 1, and 19 patients without metabolic disorders were included in group 2. Results. The levels of EPC in the peripheral blood of patients with T2DM before and after endovascular interventions were not significantly different. In the subgroup of patients without TDM2, the levels of CD34+VEGFR2 +CD45- cells increased after surgery to 55,5% (p

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

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Berezin, Alexander E

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. Copyright © 2016 Diabetes India. Published by Elsevier Ltd. All rights reserved.

In situ tissue engineering: endothelial growth patterns as a function of flow diverter design.

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Marosfoi, Miklos; Langan, Erin T; Strittmatter, Lara; van der Marel, Kajo; Vedantham, Srinivasan; Arends, Jennifer; Lylyk, Ivan R; Loganathan, Siddharth; Hendricks, Gregory M; Szikora, Istvan; Puri, Ajit S; Wakhloo, Ajay K; Gounis, Matthew J

2017-10-01

Vascular remodeling in response to implantation of a tissue engineering scaffold such as a flow diverter (FD) leads to the cure of intracranial aneurysms. We hypothesize that the vascular response is dependent on FD design, and CD34+ progenitor cells play an important role in the endothelialization of the implant. Sixteen rabbit aneurysms were randomly treated with two different single-layer braided FDs made of cobalt-chrome alloys. The FD-48 and FD-72 devices had 48 and 72 wires, respectively. Aneurysm occlusion rate was assessed during the final digital subtraction angiogram at 10, 20, 30, and 60 days (n=2 per device per time point). Implanted vessels were analyzed with scanning electron microscopy for tissue coverage, endothelialization, and immuno-gold labeling for CD34+ cells. Complete aneurysm occlusion rates were similar between the devices; however, complete or near complete occlusion was more frequently observed in aneurysms with neck ≤4.2 mm (p=0.008). Total tissue coverage at 10 days over the surface of the FD-48 and FD-72 devices was 56.4±11.6% and 76.6±3.6%, respectively. Endothelial cell growth over the surface was time-dependent for the FD-72 device (Spearman's r=0.86, p=0.013) but not for the FD-48 device (Spearman's r=-0.59, p=0.094). The endothelialization score was marginally correlated with the distance from the aneurysm neck for the FD-48 device (Spearman's r=1, p=0.083) but not for the FD-72 device (Spearman's r=0.8, p=0.33). CD34+ cells were present along the entirety of both devices at all time points. This study gives preliminary evidence that temporal and spatial endothelialization is dependent on FD design. Circulating CD34+ progenitor cells contribute to endothelialization throughout the healing process. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Black Tea Increases Circulating Endothelial Progenitor Cells and Improves Flow Mediated Dilatation Counteracting Deleterious Effects from a Fat Load in Hypertensive Patients: A Randomized Controlled Study

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Davide Grassi

2016-11-01

Full Text Available (1 Background: Endothelial dysfunction predicts cardiovascular events. Circulating angiogenic cells (CACs maintain and repair the endothelium regulating its function. Tea flavonoids reduce cardiovascular risk. We investigated the effects of black tea on the number of CACs and on flow-mediated dilation (FMD before and after an oral fat in hypertensives; (2 Methods: In a randomized, double-blind, controlled, cross-over study, 19 patients were assigned to black tea (150 mg polyphenols or a placebo twice a day for eight days. Measurements were obtained in a fasted state and after consuming whipping cream, and FMD was measured at baseline and after consumption of the products; (3 Results: Compared with the placebo, black tea ingestion increased functionally active CACs (36 ± 22 vs. 56 ± 21 cells per high-power field; p = 0.006 and FMD (5.0% ± 0.3% vs. 6.6% ± 0.3%, p < 0.0001. Tea further increased FMD 1, 2, 3, and 4 h after consumption, with maximal response 2 h after intake (p < 0.0001. Fat challenge decreased FMD, while tea consumption counteracted FMD impairment (p < 0.0001; (4 Conclusions: We demonstrated the vascular protective properties of black tea by increasing the number of CACs and preventing endothelial dysfunction induced by acute oral fat load in hypertensive patients. Considering that tea is the most consumed beverage after water, our findings are of clinical relevance and interest.

Role of integrin-linked kinase for functional capacity of endothelial progenitor cells in patients with stable coronary artery disease

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Werner, Christian; Boehm, Michael; Friedrich, Erik B.

2008-01-01

Number and function of endothelial progenitor cells (EPCs) are down-regulated in patients with coronary artery disease (CAD). Integrin-linked kinase (ILK) is a signal and adaptor protein that regulates survival of mature endothelial cells and vascular development. Here we show that EPC dysfunction in patients with CAD is paralleled by down-regulation of ILK while restoration of ILK expression rescues the migratory defect of CAD-EPCs. Human EPCs transduced with dominant-negative ILK (DN-ILK) display significantly reduced expression of CD34 + /VEGFR-2 + , DiI-Ac-LDL uptake, and Ulex europaeus lectin binding. Mechanistically, DN-ILK-transfected EPCs are characterized by decreased proliferation, while proliferation is increased in wild-type ILK-transfected EPCs. These effects are paralleled by changes in cyclin D1 expression, colony forming units, and cytoskeletal rearrangement. Functionally, ILK is necessary and sufficient for SDF-1-triggered migration and adhesion in EPCs. These data extend current knowledge about the role of ILK in EPC biology and implicate ILK as a therapeutic target in CAD.

Quantitative determination of circulating endothelial cells in persons with low dose radioactivity exposure

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Al-Massarani, Gh.; Najjar, F.

2013-04-01

The aim of this study was to determine the risk of occupational exposure to low doses of ionizing radiation on the endothelium detachment through the quantification of circulating endothelial cells (CEC) in the peripheral blood of 63 workers in the Atomic Energy Commission in Syria (AECS) using a Magnetic Immuno-separation technique (IMS) and compare the results with 28 healthy (controls) is not exposed during their careers for any type of ionizing radiation. Our study showed for the first time the significantly increasing in the circulating endothelial cells count (P <0.0001) when employees are exposed to low doses of radiation less than 50 mSv. This result with previous studies about the late effects of radiation, assuming the existence of impact late radiation exposure on the cohesion of the endothelium, despite the lack of correlation with radiation dose measured during the past four years of work in AECS (between 2006-2010). This is due to several reasons, including the small sample size and lack of commitment by some workers develop individual control films during some periods of their work. The prospective studies for such workers can allow us to know if the rise in the number of CEC will be considered an early indicator for the risk of a cardiovascular disease when workers exposed to low-doses of ionizing radiation( tens of millisievert) that up to date are considered harmless (author).

LncRNA-AK131850 Sponges MiR-93-5p in Newborn and Mature Osteoclasts to Enhance the Secretion of Vascular Endothelial Growth Factor a Promoting Vasculogenesis of Endothelial Progenitor Cells

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Hongyu Quan

2018-03-01

Full Text Available Background/Aims: In the process of bone development and remodeling, the vasculature is regarded as the communicative network between the bone and neighboring tissues. Recently, it has been reported that the processes of angiogenesis and osteogenesis are coupled temporally and spatially. However, few studies reported the relationship and relevant mechanism between osteoclastogenesis and vasculogenesis. Methods: Arraystar Mouse lncRNA microarray V3.0 was firstly used to analyze the differentially expressed lncRNA genes in osteoclast different stages during osteoclastogenesis. Cell counting kit 8 (CCK-8 analysis, quantitative real-time polymerase chain reaction (qRT-PCR analysis, migration and tube formation assays were used to detect impact of osteoclast different stages on the proliferation, differentiation, migration and tube formation of endothelial progenitor cells (EPCs, respectively. Finally, transfection of AK131850 shRNA, miR-93-5p mimic and miR-93-5p inhibitor, qRT-PCR, western blotting, enzyme-linked immunosorbent assay (ELISA, fluorescence in situ hybridization (FISH and luciferase reporter assay were carried out to dissect molecular mechanisms. Results: In this study, we found that newborn OCs (N-OC and mature OCs (M-OC during osteoclastogenesis significantly promoted proliferation, differentiation, migration and tube formation of endothelial progenitor cells (EPCs. Through lncRNA microarray and GO&pathway analysis, we found that AK131850 and co-expressed gene, vascular endothelial growth factor a (VEGFa, were significantly up-regulated in N-OC and M-OC. After inhibition of AK131850 the promoting effect of N-OC and M-OC on EPCs was reversed. Furthermore, we found that AK131850 directly competed miR-93-5p in N-OC and M-OC through sponge, thereby increasing VEGFa transcription, expression and secretion through derepressing of miR-93-5p on VEGFa. Conclusion: Our results provided the first finding that lncRNA-AK131850 sponged miR-93-5p in

Endothelial progenitor cells in long-standing asymptomatic type 1 diabetic patients with or without diabetic nephropathy

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Reinhard, Henrik; Jacobsen, Peter Karl; Lajer, Maria

2011-01-01

with or without DN and to study the effect of CVD and medication on EPC numbers. Methods: We examined EPC numbers in 37 type 1 diabetic patients with DN and 35 type 1 diabetic patients with long-standing normoalbuminuria. Patients were without symptoms of CVD and the prevalence of CVD was previously shown......A decrease in the number and dysfunction of endothelial progenitor cells (EPC) may increase the risk for progression of cardiovascular disease (CVD) in type 1 diabetic patients with diabetic nephropathy (DN). Our aim was to evaluate EPC numbers in asymptomatic CVD type 1 diabetic patients...... with CVD (p > 0.05). Conventional risk factors were significantly higher in patients with DN and they received more CVD-preventive treatment. All patients receiving simvastatin or calcium-channel blockers had higher numbers of EPC compared to patients not treated with these drugs. Conclusions: Asymptomatic...

Bone marrow-derived osteoblast progenitor cells in circulating blood contribute to ectopic bone formation in mice

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Otsuru, Satoru; Tamai, Katsuto; Yamazaki, Takehiko; Yoshikawa, Hideki; Kaneda, Yasufumi

2007-01-01

Recent studies have suggested the existence of osteoblastic cells in the circulation, but the origin and role of these cells in vivo are not clear. Here, we examined how these cells contribute to osteogenesis in a bone morphogenetic protein (BMP)-induced model of ectopic bone formation. Following lethal dose-irradiation and subsequent green fluorescent protein-transgenic bone marrow cell-transplantation (GFP-BMT) in mice, a BMP-2-containing collagen pellet was implanted into muscle. Three weeks later, a significant number of GFP-positive osteoblastic cells were present in the newly generated ectopic bone. Moreover, peripheral blood mononuclear cells (PBMNCs) from the BMP-2-implanted mouse were then shown to include osteoblast progenitor cells (OPCs) in culture. Passive transfer of the PBMNCs isolated from the BMP-2-implanted GFP-mouse to the BMP-2-implanted nude mouse led to GFP-positive osteoblast accumulation in the ectopic bone. These data provide new insight into the mechanism of ectopic bone formation involving bone marrow-derived OPCs in circulating blood

The dynamic change of endothelial cell, endothelin and 6-K-PGF1α in circulating blood of the patients with coronary heart disease

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Xia Zhiyun; Wang Linglin; Zou Songhai

1995-01-01

With the circulating endothelial cell (CEC) as an indicator of vessel endothelial cell (VEC) injury, and plasma endothelin (ET) and prostaglandin F 1α (PGI 2 ) reflecting the functional change of the VEC, a comparative study between 85 patients with coronary heart disease and 30 normal health, and also a dynamic observation of 50 patients with unstable angina pectoris and 20 patients with acute myocardial infarction (AMI) were reported. The result showed that in patients with coronary heart disease, peripheral blood circulating CEC and ET level was increased (P 2 decreased (P<0.01). All these were more significant in patients with unstable angina pectoris and myocardial infarction, and its magnitude correlated closely with the severity of the disease. All these showed that the VEC injury and the imbalance of its endothelial relaxing and contracting factors have played an important role in the pathogenesis of coronary heart disease

Human endothelial progenitor cells internalize high-density lipoprotein.

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Kaemisa Srisen

Full Text Available Endothelial progenitor cells (EPCs originate either directly from hematopoietic stem cells or from a subpopulation of monocytes. Controversial views about intracellular lipid traffic prompted us to analyze the uptake of human high density lipoprotein (HDL, and HDL-cholesterol in human monocytic EPCs. Fluorescence and electron microscopy were used to investigate distribution and intracellular trafficking of HDL and its associated cholesterol using fluorescent surrogates (bodipy-cholesterol and bodipy-cholesteryl oleate, cytochemical labels and fluorochromes including horseradish peroxidase and Alexa Fluor® 568. Uptake and intracellular transport of HDL were demonstrated after internalization periods from 0.5 to 4 hours. In case of HDL-Alexa Fluor® 568, bodipy-cholesterol and bodipy-cholesteryl oleate, a photooxidation method was carried out. HDL-specific reaction products were present in invaginations of the plasma membrane at each time of treatment within endocytic vesicles, in multivesicular bodies and at longer periods of uptake, also in lysosomes. Some HDL-positive endosomes were arranged in form of "strings of pearl"- like structures. HDL-positive multivesicular bodies exhibited intensive staining of limiting and vesicular membranes. Multivesicular bodies of HDL-Alexa Fluor® 568-treated EPCs showed multilamellar intra-vacuolar membranes. At all periods of treatment, labeled endocytic vesicles and organelles were apparent close to the cell surface and in perinuclear areas around the Golgi apparatus. No HDL-related particles could be demonstrated close to its cisterns. Electron tomographic reconstructions showed an accumulation of HDL-containing endosomes close to the trans-Golgi-network. HDL-derived bodipy-cholesterol was localized in endosomal vesicles, multivesicular bodies, lysosomes and in many of the stacked Golgi cisternae and the trans-Golgi-network Internalized HDL-derived bodipy-cholesteryl oleate was channeled into the lysosomal

WISP-3 inhibition of miR-452 promotes VEGF-A expression in chondrosarcoma cells and induces endothelial progenitor cells angiogenesis.

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Lin, Chih-Yang; Tzeng, Huey-En; Li, Te-Mao; Chen, Hsien-Te; Lee, Yi; Yang, Yi-Chen; Wang, Shih-Wei; Yang, Wei-Hung; Tang, Chih-Hsin

2017-06-13

Chondrosarcoma is the second most prevalent general primary tumor of bone following osteosarcoma. Chondrosarcoma development may be linked to angiogenesis, which is principally elicited by vascular endothelial growth factor-A (VEGF-A). VEGF-A level has been recognized as a prognostic marker in angiogenesis. WNT1-inducible signaling pathway protein-3 (WISP)-3/CCN6 belongs to the CCN family and is involved in regulating several cellular functions, including cell proliferation, differentiation, and migration. Nevertheless, the effect of WISP-3 on VEGF-A production and angiogenesis in human chondrosarcoma remains largely unknown. This current study shows that WISP-3 promoted VEGF-A production and induced angiogenesis of human endothelial progenitor cells. Moreover, WISP-3-enhanced VEGF-A expression and angiogenesis involved the c-Src and p38 signaling pathways, while miR-452 expression was negatively affected by WISP-3 via the c-Src and p38 pathways. Our results illustrate the clinical significance of WISP-3, VEGF-A and miR-452 in human chondrosarcoma patients. WISP-3 may illustrate a novel therapeutic target in the metastasis and angiogenesis of chondrosarcoma.

Mobilization of endogenous bone marrow derived endothelial progenitor cells and therapeutic potential of parathyroid hormone after ischemic stroke in mice.

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Li-Li Wang

Full Text Available Stroke is a major neurovascular disorder threatening human life and health. Very limited clinical treatments are currently available for stroke patients. Stem cell transplantation has shown promising potential as a regenerative treatment after ischemic stroke. The present investigation explores a new concept of mobilizing endogenous stem cells/progenitor cells from the bone marrow using a parathyroid hormone (PTH therapy after ischemic stroke in adult mice. PTH 1-34 (80 µg/kg, i.p. was administered 1 hour after focal ischemia and then daily for 6 consecutive days. After 6 days of PTH treatment, there was a significant increase in bone marrow derived CD-34/Fetal liver kinase-1 (Flk-1 positive endothelial progenitor cells (EPCs in the peripheral blood. PTH treatment significantly increased the expression of trophic/regenerative factors including VEGF, SDF-1, BDNF and Tie-1 in the brain peri-infarct region. Angiogenesis, assessed by co-labeled Glut-1 and BrdU vessels, was significantly increased in PTH-treated ischemic brain compared to vehicle controls. PTH treatment also promoted neuroblast migration from the subventricular zone (SVZ and increased the number of newly formed neurons in the peri-infarct cortex. PTH-treated mice showed significantly better sensorimotor functional recovery compared to stroke controls. Our data suggests that PTH therapy improves endogenous repair mechanisms after ischemic stroke with functional benefits. Mobilizing endogenous bone marrow-derived stem cells/progenitor cells using PTH and other mobilizers appears an effective and feasible regenerative treatment after ischemic stroke.

Interleukin-3 greatly expands non-adherent endothelial forming cells with pro-angiogenic properties

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Lachlan M. Moldenhauer

2015-05-01

Full Text Available Circulating endothelial progenitor cells (EPCs provide revascularisation for cardiovascular disease and the expansion of these cells opens up the possibility of their use as a cell therapy. Herein we show that interleukin-3 (IL3 strongly expands a population of human non-adherent endothelial forming cells (EXnaEFCs with low immunogenicity as well as pro-angiogenic capabilities in vivo, making their therapeutic utilisation a realistic option. Non-adherent CD133+ EFCs isolated from human umbilical cord blood and cultured under different conditions were maximally expanded by day 12 in the presence of IL3 at which time a 350-fold increase in cell number was obtained. Cell surface marker phenotyping confirmed expression of the hematopoietic progenitor cell markers CD133, CD117 and CD34, vascular cell markers VEGFR2 and CD31, dim expression of CD45 and absence of myeloid markers CD14 and CD11b. Functional experiments revealed that EXnaEFCs exhibited classical properties of endothelial cells (ECs, namely binding of Ulex europaeus lectin, up-take of acetylated-low density lipoprotein and contribution to EC tube formation in vitro. These EXnaEFCs demonstrated a pro-angiogenic phenotype within two independent in vivo rodent models. Firstly, a Matrigel plug assay showed increased vascularisation in mice. Secondly, a rat model of acute myocardial infarction demonstrated reduced heart damage as determined by lower levels of serum creatinine and a modest increase in heart functionality. Taken together, these studies show IL3 as a potent growth factor for human CD133+ cell expansion with clear pro-angiogenic properties (in vitro and in vivo and thus may provide clinical utility for humans in the future.

Alcohol consumption negates estrogen-mediated myocardial repair in ovariectomized mice by inhibiting endothelial progenitor cell mobilization and function.

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Mackie, Alexander R; Krishnamurthy, Prasanna; Verma, Suresh K; Thorne, Tina; Ramirez, Veronica; Qin, Gangjian; Abramova, Tatiana; Hamada, Hiromichi; Losordo, Douglas W; Kishore, Raj

2013-06-21

We have shown previously that estrogen (estradiol, E2) supplementation enhances voluntary alcohol consumption in ovariectomized female rodents and that increased alcohol consumption impairs ischemic hind limb vascular repair. However, the effect of E2-induced alcohol consumption on post-infarct myocardial repair and on the phenotypic/functional properties of endothelial progenitor cells (EPCs) is not known. Additionally, the molecular signaling of alcohol-estrogen interactions remains to be elucidated. This study examined the effect of E2-induced increases in ethanol consumption on post-infarct myocardial function/repair. Ovariectomized female mice, implanted with 17β-E2 or placebo pellets were given access to alcohol for 6 weeks and subjected to acute myocardial infarction. Left ventricular functions were consistently depressed in mice consuming ethanol compared with those receiving only E2. Alcohol-consuming mice also displayed significantly increased infarct size and reduced capillary density. Ethanol consumption also reduced E2-induced mobilization and homing of EPCs to injured myocardium compared with the E2-alone group. In vitro, exposure of EPCs to ethanol suppressed E2-induced proliferation, survival, and migration and markedly altered E2-induced estrogen receptor-dependent cell survival signaling and gene expression. Furthermore, ethanol-mediated suppression of EPC biology was endothelial nitric oxide synthase-dependent because endothelial nitric oxide synthase-null mice displayed an exaggerated response to post-acute myocardial infarction left ventricular functions. These data suggest that E2 modulation of alcohol consumption, and the ensuing EPC dysfunction, may negatively compete with the beneficial effects of estrogen on post-infarct myocardial repair.

Nigral dopaminergic neuron replenishment in adult mice through VE-cadherin-expressing neural progenitor cells

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Abir A Rahman

2017-01-01

Full Text Available The function of dopaminergic neurons in the substantia nigra is of central importance to the coordination of movement by the brain's basal ganglia circuitry. This is evidenced by the loss of these neurons, resulting in the cardinal motor deficits associated with Parkinson's disease. In order to fully understand the physiology of these key neurons and develop potential therapies for their loss, it is essential to determine if and how dopaminergic neurons are replenished in the adult brain. Recent work has presented evidence for adult neurogenesis of these neurons by Nestin+/Sox2– neural progenitor cells. We sought to further validate this finding and explore a potential atypical origin for these progenitor cells. Since neural progenitor cells have a proximal association with the vasculature of the brain and subsets of endothelial cells are Nestin+, we hypothesized that dopaminergic neural progenitors might share a common cell lineage. Therefore, we employed a VE-cadherin promoter-driven CREERT2:THlox/THlox transgenic mouse line to ablate the tyrosine hydroxylase gene from endothelial cells in adult animals. After 26 weeks, but not 13 weeks, following the genetic blockade of tyrosine hydroxylase expression in VE-cadherin+ cells, we observed a significant reduction in tyrosine hydroxylase+ neurons in the substantia nigra. The results from this genetic lineage tracing study suggest that dopaminergic neurons are replenished in adult mice by a VE-cadherin+ progenitor cell population potentially arising from an endothelial lineage.

Endothelial glycocalyx on brain endothelial cells is lost in experimental cerebral malaria

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Hempel, Casper; Hyttel, Poul; Kurtzhals, Jørgen Al

2014-01-01

We hypothesized that the glycocalyx, which is important for endothelial integrity, is lost in severe malaria. C57BL/6 mice were infected with Plasmodium berghei ANKA, resulting in cerebral malaria, or P. chabaudi AS, resulting in uncomplicated malaria. We visualized the glycocalyx with transmission...... electron microscopy and measured circulating glycosaminoglycans by dot blot and ELISA. The glycocalyx was degraded in brain vasculature in cerebral and to a lesser degree uncomplicated malaria. It was affected on both intact and apoptotic endothelial cells. Circulating glycosaminoglycan levels suggested...

Hypoxia, leukocytes, and the pulmonary circulation.

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Stenmark, Kurt R; Davie, Neil J; Reeves, John T; Frid, Maria G

2005-02-01

Data are rapidly accumulating in support of the idea that circulating monocytes and/or mononuclear fibrocytes are recruited to the pulmonary circulation of chronically hypoxic animals and that these cells play an important role in the pulmonary hypertensive process. Hypoxic induction of monocyte chemoattractant protein-1, stromal cell-derived factor-1, vascular endothelial growth factor-A, endothelin-1, and tumor growth factor-beta(1) in pulmonary vessel wall cells, either directly or indirectly via signals from hypoxic lung epithelial cells, may be a critical first step in the recruitment of circulating leukocytes to the pulmonary circulation. In addition, hypoxic stress appears to induce release of increased numbers of monocytic progenitor cells from the bone marrow, and these cells may have upregulated expression of receptors for the chemokines produced by the lung circulation, which thus facilitates their specific recruitment to the pulmonary site. Once present, macrophages/fibrocytes may exert paracrine effects on resident pulmonary vessel wall cells stimulating proliferation, phenotypic modulation, and migration of resident fibroblasts and smooth muscle cells. They may also contribute directly to the remodeling process through increased production of collagen and/or differentiation into myofibroblasts. In addition, they could play a critical role in initiating and/or supporting neovascularization of the pulmonary artery vasa vasorum. The expanded vasa network may then act as a conduit for further delivery of circulating mononuclear cells to the pulmonary arterial wall, creating a feedforward loop of pathological remodeling. Future studies will need to determine the mechanisms that selectively induce leukocyte/fibrocyte recruitment to the lung circulation under hypoxic conditions, their direct role in the remodeling process via production of extracellular matrix and/or differentiation into myofibroblasts, their impact on the phenotype of resident smooth muscle

Effect of a Mediterranean diet on endothelial progenitor cells and carotid intima-media thickness in type 2 diabetes: Follow-up of a randomized trial.

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Maiorino, Maria Ida; Bellastella, Giuseppe; Petrizzo, Michela; Gicchino, Maurizio; Caputo, Mariangela; Giugliano, Dario; Esposito, Katherine

2017-03-01

Background We assessed the long-term effects of a Mediterranean diet on circulating levels of endothelial progenitor cells (EPCs) and the carotid intima-media thickness (CIMT) in patients with type 2 diabetes. Design This was a parallel, two-arm, single-centre trial. Methods Two hundred and fifteen men and women with newly diagnosed type 2 diabetes were randomized to a Mediterranean diet ( n = 108) or a low-fat diet ( n = 107). The primary outcome measures were changes in the EPC count and the CIMT of the common carotid artery after the treatment period defined as the end of trial (EOT). Results At the EOT, both the CD34 + KDR + and CD34 + KDR + CD133 + counts had increased with the Mediterranean diet compared with the low-fat diet ( p Mediterranean diet. Compared with the low-fat diet, the rate of regression in the CIMT was higher in the Mediterranean diet group (51 vs. 26%), whereas the rate of progression was lower (25 vs. 50%) ( p = 0.032 for both). Changes in the CIMT were inversely correlated with the changes in EPC levels (CD34 + KDR + , r = -0.24, p = 0.020; CD34 + KDR + CD133 + , r = -0.28, p = 0.014). At the EOT, changes in levels of HbA1c, HOMA, total cholesterol, high-density lipoprotein cholesterol and systolic blood pressure were significantly greater with the Mediterranean diet than with the low-fat diet. Conclusion Compared with a low-fat diet, a long-term trial with Mediterranean diet was associated with an increase in circulating EPCs levels and prevention of the progression of subclinical atherosclerosis in patients with newly diagnosed type 2 diabetes.

Vascular smooth muscle cells for use in vascular tissue engineering obtained by endothelial-to-mesenchymal transdifferentiation (EnMT) on collagen matrices

NARCIS (Netherlands)

Krenning, Guido; Moonen, Jan-Renier A. J.; van Luyn, Marja J. A.; Harmsen, Martin C.

The discovery of the endothelial progenitor cell (EPC) has led to an intensive research effort into progenitor cell-based tissue engineering of (small-diameter) blood vessels. Herein, EPC are differentiated to vascular endothelial cells and serve as the inner lining of bioartificial vessels. As yet,

Optimized multiparametric flow cytometric analysis of circulating endothelial cells and their subpopulations in peripheral blood of patients with solid tumors: a technical analysis

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Zhou F

2018-03-01

with solid tumors. Several key technical issues regarding preanalytical elements, FCM data acquisition, and analysis were addressed. Furthermore, we clinically validated the utility of our method. The baseline levels of mature CECs, endothelial progenitor cells, and activated CECs were higher in cancer patients than healthy subjects (P<0.01. However, there was no significant difference in resting CEC levels between healthy subjects and cancer patients (P=0.193.Conclusion: We integrated and comprehensively addressed significant technical issues found in previously published assays and validated the reproducibility and sensitivity of our proposed method. Future work is required to explore the potential of our optimized method in clinical oncologic applications. Keywords: circulating endothelial cells, CECs, CEC subpopulations, flow cytometry, methods

Topical application of ex vivo expanded endothelial progenitor cells promotes vascularisation and wound healing in diabetic mice.

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Asai, Jun; Takenaka, Hideya; Ii, Masaaki; Asahi, Michio; Kishimoto, Saburo; Katoh, Norito; Losordo, Douglas W

2013-10-01

Impaired wound healing leading to skin ulceration is a serious complication of diabetes and may be caused by defective angiogenesis. Endothelial progenitor cells (EPCs) can augment neovascularisation in the ischaemic tissue. Experiments were performed to test the hypothesis that locally administered EPCs can promote wound healing in diabetes. Full-thickness skin wounds were created on the dorsum of diabetic mice. EPCs were obtained from bone marrow mononuclear cells (BMMNCs) and applied topically to the wound immediately after surgery. Vehicle and non-selective BMMNCs were used as controls. Wound size was measured on days 5, 10 and 14 after treatment, followed by resection, histological analysis and quantification of vascularity. Topical application of EPCs significantly promoted wound healing, as assessed by closure rate and wound vascularity. Immunostaining revealed that transplanted EPCs induced increased expression of vascular endothelial growth factor and basic fibroblast growth factor. Few EPCs were observed in the neovasculature based on in vivo staining of the functional vasculature. Ex vivo expanded EPCs promote wound healing in diabetic mice via mechanisms involving increased local cytokine expression and enhanced neovascularisation of the wound. This strategy exploiting the therapeutic capacity of autologously derived EPCs may be a novel approach to skin repair in diabetes. © 2012 The Authors. International Wound Journal © 2012 John Wiley & Sons Ltd and Medicalhelplines.com Inc.

Resveratrol Improves Tube Formation in AGE-Induced Late Endothelial Progenitor Cells by Suppressing Syndecan-4 Shedding

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Han Wu

2018-01-01

Full Text Available Dysfunction of endothelial progenitor cells (EPCs contributes to cardiovascular complications in diabetes, and resveratrol has been shown to improve EPC functions. Syndecan-4 (Synd4, a cell surface heparin sulfate proteoglycan, has been shown to promote neovascularization. Thus, the present study was performed to determine whether resveratrol promoted angiogenesis of EPCs by regulating Synd4. Late EPCs were isolated from human peripheral blood and stimulated with AGEs. Western blot showed that AGEs induced Synd4 shedding in a dose- and time-dependent manner. AGE-induced Synd4 shedding was partly reversed by NAC or resveratrol, along with normalized ROS production. Overexpression of Synd4 or pretreatment of resveratrol reversed AGE-impaired tube formation of EPCs and regulated the Akt/eNOS pathway. Furthermore, resveratrol suppressed Synd4 shedding via the inhibition of oxidative stress and improved tube formation of late EPCs via the regulation of the Synd4/Akt/eNOS pathway.

Circulating endothelial cells (CECs and E-selectin: Predictors of preeclampsia

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Ferdous Mehrabian

2012-01-01

Full Text Available Background: Circulating endothelial cells (CECs and E-selectin are known as sensitive and specific markers of en-dothelial dysfunction. This study investigated whether CECs and E-selectin are surrogate biomarkers of preeclampsia and if measurement of CECs and E-selectin, early in the third trimester, could be a means of predicting preeclampsia. Methods: In this prospective, descriptive-analytic study, rollover test was performed on 523 pregnant women during 28-30 weeks of gestation. CECs were measured by anti-CD 146-driven immunomagnetic isolation in women with posi-tive rollover test. They were followed up prospectively until delivery without any active intervention. Women with and without preeclampsia were determined. The number of CECs and level of E-selectin were compared in the two studied groups. Results: From the 47 pregnant women with positive rollover test who were selected and followed up, 22 individuals were diagnosed with preeclampsia while the remainder were normotensive. Mean CEC numbers was significantly high-er in preeclamptic women than normal pregnancies (24.7 cells/mL vs. 13 cells/mL. The best cut-off point for CEC numbers was 6.5 with a sensitivity of 78.9% and a specificity of 69.1%. The level of E-selectin was significantly higher in mothers with preeclampsia (p < 0.05. Conclusions: Higher levels of CECs and E-selectin in women with positive rollover test who developed preeclampsia prior to onset of the complication were predictive of preeclampsia. However, larger studies are needed to confirm these findings.

Endothelial Cells Control Pancreatic Cell Fate at Defined Stages through EGFL7 Signaling

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Der-I Kao

2015-02-01

Full Text Available Although endothelial cells have been shown to affect mouse pancreatic development, their precise function in human development remains unclear. Using a coculture system containing human embryonic stem cell (hESC-derived progenitors and endothelial cells, we found that endothelial cells play a stage-dependent role in pancreatic development, in which they maintain pancreatic progenitor (PP self-renewal and impair further differentiation into hormone-expressing cells. The mechanistic studies suggest that the endothelial cells act through the secretion of EGFL7. Consistently, endothelial overexpression of EGFL7 in vivo using a transgenic mouse model resulted in an increase of PP proliferation rate and a decrease of differentiation toward endocrine cells. These studies not only identified the role of EGFL7 as the molecular handle involved in the crosstalk between endothelium and pancreatic epithelium, but also provide a paradigm for using hESC stepwise differentiation to dissect the stage-dependent roles of signals controlling organogenesis.

Advanced glycation end products impair function of late endothelial progenitor cells through effects on protein kinase Akt and cyclooxygenase-2

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Chen Qin; Dong Li; Wang Lian; Kang Lina; Xu Biao

2009-01-01

Endothelial progenitor cells (EPCs) exhibit impaired function in the context of diabetes, and advanced glycation end products (AGEs), which accumulate in diabetes, may contribute to this. In the present study, we investigated the mechanism by which AGEs impair late EPC function. EPCs from human umbilical cord blood were isolated, and incubated with AGE-modified albumin (AGE-albumin) at different concentrations found physiologically in plasma. Apoptosis, migration, and tube formation assays were used to evaluate EPC function including capacity for vasculogenesis, and expression of the receptor for AGEs (RAGE), Akt, endothelial nitric oxide synthase (eNOS), and cycloxygenase-2 (COX-2) were determined. Anti-RAGE antibody was used to block RAGE function. AGE-albumin concentration-dependently enhanced apoptosis and depressed migration and tube formation, but did not affect proliferation, of late EPCs. High AGE-albumin increased RAGE mRNA and protein expression, and decreased Akt and COX-2 protein expression, whilst having no effect on eNOS mRNA or protein in these cells. These effects were inhibited by co-incubation with anti-RAGE antibody. These results suggest that RAGE mediates the AGE-induced impairment of late EPC function, through down-regulation of Akt and COX-2 in these cells.

[The role of endothelial cells and endothelial precursor cells in angiogenesis].

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Poreba, Małgorzata; Usnarska-Zubkiewicz, Lidia; Kuliczkowski, Kazimierz

2006-01-01

Endothelium plays a key role in maintenance of vascular homeostasis in human organism. According to new data endothelial cells and hematopoietic cells have a common precursor in prenatal life--a hemangioblast, which explains the fact of sharing the same determinants on the surface of both type of cells. Circulating endothelial precursors were identified in adults and this suggests that hemangioblasts may be present not only during embriogenesis. In some clinical situations the increased numbers of endothelial cells and endothelial precursors were noted, and especially in patients with neoplastic diseases, which is probably the result of increased angiogenesis. Endothelial precursors are thought to be the promice for therapeutic purposes in future--to increase local angiogenesis.

Transfusion of CXCR4-primed endothelial progenitor cells reduces cerebral ischemic damage and promotes repair in db/db diabetic mice.

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Ji Chen

Full Text Available This study investigated the role of stromal cell-derived factor-1α (SDF-1α/CXC chemokine receptor 4 (CXCR4 axis in brain and endothelial progenitor cells (EPCs, and explored the efficacy of CXCR4 primed EPCs in treating ischemic stroke in diabetes. The db/db diabetic and db/+ mice were used in this study. Levels of plasma SDF-1α and circulating CD34+CXCR4+ cells were measured. Brain SDF-1α and CXCR4 expression were quantified at basal and after middle cerebral artery occlusion (MCAO. In in vitro study, EPCs were transfected with adenovirus carrying null (Ad-null or CXCR4 (Ad-CXCR4 followed with high glucose (HG treatment for 4 days. For pathway block experiments, cells were pre-incubated with PI3K inhibitor or nitric oxide synthase (NOS inhibitor for two hours. The CXCR4 expression, function and apoptosis of EPCs were determined. The p-Akt/Akt and p-eNOS/eNOS expression in EPCs were also measured. In in vivo study, EPCs transfected with Ad-null or Ad-CXCR4 were infused into mice via tail vein. On day 2 and 7, the cerebral blood flow, neurologic deficit score, infarct volume, cerebral microvascular density, angiogenesis and neurogenesis were determined. We found: 1 The levels of plasma SDF-1α and circulating CD34+CXCR4+ cells were decreased in db/db mice; 2 The basal level of SDF-1α and MCAO-induced up-regulation of SDF-1α/CXCR4 axis were reduced in the brain of db/db mice; 3 Ad-CXCR4 transfection increased CXCR4 expression in EPCs and enhanced EPC colonic forming capacity; 4 Ad-CXCR4 transfection prevented EPCs from HG-induced dysfunction (migration and tube formation and apoptosis via activation of PI3K/Akt/eNOS signal pathway; 4 Ad-CXCR4 transfection enhanced the efficacy of EPC infusion in attenuating infarct volume and promoting angiogenesis and neurogenesis. Our data suggest that Ad-CXCR4 primed EPCs have better therapeutic effects for ischemia stroke in diabetes than unmodified EPCs do.

Indoxyl Sulfate Impairs Endothelial Progenitor Cells and Might Contribute to Vascular Dysfunction in Patients with Chronic Kidney Disease

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Cheng-Jui Lin

2016-12-01

Full Text Available Background/Aims: Indoxyl sulfate (IS is a protein-bound uremic toxin that accumulates in patients with chronic kidney disease (CKD. We explored the effect of IS on human early endothelial progenitor cells (EPCs and analyzed the correlation between serum IS levels and parameters of vascular function, including endothelial function in a CKD-based cohort. Methods: A cross-sectional study with 128 stable CKD patients was conducted. Flow-mediated dilation (FMD, pulse wave velocity (PWV, ankle brachial index, serum IS and other biochemical parameters were measured and analyzed. In parallel, the activity of early EPCs was also evaluated after exposure to IS. Results: In human EPCs, a concentration-dependent inhibitory effect of IS on chemotactic motility and colony formation was observed. Additionally, serum IS levels were significantly correlated with CKD stages. The total IS (T-IS and free IS (F-IS were strongly associated with age, hypertension, cardiovascular disease, blood pressure, PWV, blood urea nitrogen, creatine and phosphate but negatively correlated with FMD, the estimated glomerular filtration rate (eGFR, hemoglobin, hematocrit, and calcium. A multivariate linear regression analysis also showed that FMD was significantly associated with IS after adjusting for other confounding factors. Conclusions: In humans, IS impairs early EPCs and was strongly correlated with vascular dysfunction. Thus, we speculate that this adverse effect of IS may partly result from the inhibition of early EPCs.

Arachidonic acid metabolites and endothelial dysfunction of portal hypertension.

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Sacerdoti, David; Pesce, Paola; Di Pascoli, Marco; Brocco, Silvia; Cecchetto, Lara; Bolognesi, Massimo

2015-07-01

Increased resistance to portal flow and increased portal inflow due to mesenteric vasodilatation represent the main factors causing portal hypertension in cirrhosis. Endothelial cell dysfunction, defined as an imbalance between the synthesis, release, and effect of endothelial mediators of vascular tone, inflammation, thrombosis, and angiogenesis, plays a major role in the increase of resistance in portal circulation, in the decrease in the mesenteric one, in the development of collateral circulation. Reduced response to vasodilators in liver sinusoids and increased response in the mesenteric arterioles, and, viceversa, increased response to vasoconstrictors in the portal-sinusoidal circulation and decreased response in the mesenteric arterioles are also relevant to the pathophysiology of portal hypertension. Arachidonic acid (AA) metabolites through the three pathways, cyclooxygenase (COX), lipoxygenase, and cytochrome P450 monooxygenase and epoxygenase, are involved in endothelial dysfunction of portal hypertension. Increased thromboxane-A2 production by liver sinusoidal endothelial cells (LSECs) via increased COX-1 activity/expression, increased leukotriens, increased epoxyeicosatrienoic acids (EETs) (dilators of the peripheral arterial circulation, but vasoconstrictors of the portal-sinusoidal circulation), represent a major component in the increased portal resistance, in the decreased portal response to vasodilators and in the hyper-response to vasoconstrictors. Increased prostacyclin (PGI2) via COX-1 and COX-2 overexpression, and increased EETs/heme-oxygenase-1/K channels/gap junctions (endothelial derived hyperpolarizing factor system) play a major role in mesenteric vasodilatation, hyporeactivity to vasoconstrictors, and hyper-response to vasodilators. EETs, mediators of liver regeneration after hepatectomy and of angiogenesis, may play a role in the development of regenerative nodules and collateral circulation, through stimulation of vascular endothelial

New insights into circulating FABP4: Interaction with cytokeratin 1 on endothelial cell membranes.

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Saavedra, Paula; Girona, Josefa; Bosquet, Alba; Guaita, Sandra; Canela, Núria; Aragonès, Gemma; Heras, Mercedes; Masana, Lluís

2015-11-01

Fatty acid-binding protein 4 (FABP4) is an adipose tissue-secreted adipokine that is involved in the regulation of energetic metabolism and inflammation. Increased levels of circulating FABP4 have been detected in individuals with cardiovascular risk factors. Recent studies have demonstrated that FABP4 has a direct effect on peripheral tissues, specifically promoting vascular dysfunction; however, its mechanism of action is unknown. The objective of this work was to assess the specific interactions between exogenous FABP4 and the plasma membranes of endothelial cells. Immunofluorescence assays showed that exogenous FABP4 localized along the plasma membranes of human umbilical vein endothelial cells (HUVECs), interacting specifically with plasma membrane proteins. Anti-FABP4 immunoblotting revealed two covalent protein complexes containing FABP4 and its putative receptor; these complexes were approximately 108 kDa and 77 kDa in size. Proteomics and mass spectrometry experiments revealed that cytokeratin 1 (CK1) was the FABP4-binding protein. An anti-CK1 immunoblot confirmed the presence of CK1. FABP4-CK1 complexes were also detected in HAECs, HCASMCs, HepG2 cells and THP-1 cells. Pharmacological FABP4 inhibition by BMS309403 results in a slight decrease in the formation of these complexes, indicating that fatty acids may play a role in FABP4 functionality. In addition, we demonstrated that exogenous FABP4 crosses the plasma membrane to enter the cytoplasm and nucleus in HUVECs. These findings indicate that exogenous FABP4 interacts with plasma membrane proteins, specifically CK1. These data contribute to our current knowledge regarding the mechanism of action of circulating FABP4.

Immobilization of serum albumin and peptide aptamer for EPC on polydopamine coated titanium surface for enhanced in-situ self-endothelialization

International Nuclear Information System (INIS)

Chen, Zhuoyue; Li, Quanli; Chen, Jialong; Luo, Rifang; Maitz, Manfred F.; Huang, Nan

2016-01-01

Restenosis and thrombosis are two major complications associated with vascular stents and grafts. The homing of circulating endothelial progenitor cells (EPCs) onto implant surfaces brings a new strategy to solve these problems by accelerating self -endothelialization in situ. Peptide aptamers with high affinity and specific recognition of EPCs can be immobilized to capture EPCs from the circulating blood. In this study, a biotinylated peptide aptamer (TPSLEQRTVYAK-GGGC-K-Biotin) for EPC, and bovine serum albumin (BSA) were co-immobilized onto titanium surface through avidin–biotin recognition to endow the surface with specific affinity for EPC and anti-platelet adhesion properties. Quartz crystal microbalance with dissipation (QCM-D), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and water contact angle measuring were adopted for coating characterization. EPC affinity and hemocompatibility of the coating were also investigated in vitro. The results demonstrated that aptamer and BSA co-immobilized surface significantly reduced platelet adhesion and fibrinogen adsorption/activation. Besides, such functional surface could remarkably enhance EPC adhesion, without affecting the behavior of endothelial cells (ECs) and smooth muscle cells (SMCs) obviously. The result shows the possibility of utilizing such a multifunctional surface in cardiovascular implants. - Highlights: • We construct a multifunctional surface based on immobilization of BSA and aptamer. • It can significantly reduce platelet adhesion and fibrinogen adsorption/activation. • Such functional surface could remarkably enhance EPC adhesion in vitro. • It can induce rapid self-endothelialization of the implant surface in situ in vivo. • It is possible to use such a multifunctional surface in cardiovascular implants.

Immobilization of serum albumin and peptide aptamer for EPC on polydopamine coated titanium surface for enhanced in-situ self-endothelialization

Energy Technology Data Exchange (ETDEWEB)

Chen, Zhuoyue, E-mail: 362947953@qq.com [Key Lab. of Advanced Technology for Materials of Education Ministry, Southwest Jiaotong University, Chengdu, 610031 (China); RegeMed Lab of Tissue Engineering, Faculty of Life Science, Northwest University, Xi' an, 710069 (China); Li, Quanli [College of Stomology, Anhui Medical University, Hefei, 230032 (China); Chen, Jialong [Key Lab. of Advanced Technology for Materials of Education Ministry, Southwest Jiaotong University, Chengdu, 610031 (China); College of Stomology, Anhui Medical University, Hefei, 230032 (China); Luo, Rifang [Key Lab. of Advanced Technology for Materials of Education Ministry, Southwest Jiaotong University, Chengdu, 610031 (China); Maitz, Manfred F. [Key Lab. of Advanced Technology for Materials of Education Ministry, Southwest Jiaotong University, Chengdu, 610031 (China); Leibniz Institute of Polymer Research Dresden, Max Bergmann Center of Biomaterials, Dresden (Germany); Huang, Nan, E-mail: huangnan1956@163.com [Key Lab. of Advanced Technology for Materials of Education Ministry, Southwest Jiaotong University, Chengdu, 610031 (China)

2016-03-01

Restenosis and thrombosis are two major complications associated with vascular stents and grafts. The homing of circulating endothelial progenitor cells (EPCs) onto implant surfaces brings a new strategy to solve these problems by accelerating self -endothelialization in situ. Peptide aptamers with high affinity and specific recognition of EPCs can be immobilized to capture EPCs from the circulating blood. In this study, a biotinylated peptide aptamer (TPSLEQRTVYAK-GGGC-K-Biotin) for EPC, and bovine serum albumin (BSA) were co-immobilized onto titanium surface through avidin–biotin recognition to endow the surface with specific affinity for EPC and anti-platelet adhesion properties. Quartz crystal microbalance with dissipation (QCM-D), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and water contact angle measuring were adopted for coating characterization. EPC affinity and hemocompatibility of the coating were also investigated in vitro. The results demonstrated that aptamer and BSA co-immobilized surface significantly reduced platelet adhesion and fibrinogen adsorption/activation. Besides, such functional surface could remarkably enhance EPC adhesion, without affecting the behavior of endothelial cells (ECs) and smooth muscle cells (SMCs) obviously. The result shows the possibility of utilizing such a multifunctional surface in cardiovascular implants. - Highlights: • We construct a multifunctional surface based on immobilization of BSA and aptamer. • It can significantly reduce platelet adhesion and fibrinogen adsorption/activation. • Such functional surface could remarkably enhance EPC adhesion in vitro. • It can induce rapid self-endothelialization of the implant surface in situ in vivo. • It is possible to use such a multifunctional surface in cardiovascular implants.

Complications impaired endothelial progenitor cell function in Type 2 diabetic patients with or without critical leg ischaemia: implication for impaired neovascularization in diabetes.

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Chen, M-C; Sheu, J-J; Wang, P-W; Chen, C-Y; Kuo, M-C; Hsieh, C-J; Chen, J-F; Chang, H-W

2009-02-01

This study tested the hypothesis that migratory function of endothelial progenitor cells (EPCs) is impaired in Type 2 diabetic patients with or without critical leg ischaemia. Seventy-four patients were classified into four groups: Type 2 diabetic (n = 21) and non-diabetic patients (n = 10) with critical leg ischaemia and Type 2 diabetic patients without lower extremity vascular disease (n = 30) and healthy subjects (n = 13). The number and functional activity of circulating and cultured EPCs were determined. The migratory function of cultured EPCs was significantly impaired in diabetic patients without (median, 48, interquartile range, 46, 49 count/view/well) and with (median, 51, interquartile range, 46, 60 count/view/well) critical leg ischaemia and non-diabetic patients with critical leg ischaemia (median, 49, interquartile range, 47, 55 count/view/well) compared with healthy subjects (median, 63, interquartile range, 57, 65 count/view/well) (P interquartile range, 1600, 6600/10(6) cytometric events) than Type 2 diabetic patients with critical leg ischaemia (median, 5300, interquartile range, 2400, 11,100/10(6) cytometric events), non-diabetic patients with critical leg ischaemia (median, 5550, interquartile range, 2000, 32,100/10(6) cytometric events) and healthy subjects (median, 5400, interquartile range, 2700, 8700/10(6) cytometric events) (P = 0.413). The migratory function of EPCs is impaired in patients with Type 2 diabetes, even in those without critical leg ischaemia. These findings present an important new insight into the pathogenesis of impaired neovascularization and critical limb ischaemia in diabetic patients and provide avenues of future clinical study.

Development of hematopoietic stem and progenitor cells from human pluripotent stem cells.

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Chen, Tong; Wang, Fen; Wu, Mengyao; Wang, Zack Z

2015-07-01

Human pluripotent stem cells (hPSCs), including human embryonic stem cells (hESCs) and human induced pluripotent stem cells (hiPSCs), provide a new cell source for regenerative medicine, disease modeling, drug discovery, and preclinical toxicity screening. Understanding of the onset and the sequential process of hematopoietic cells from differentiated hPSCs will enable the achievement of personalized medicine and provide an in vitro platform for studying of human hematopoietic development and disease. During embryogenesis, hemogenic endothelial cells, a specified subset of endothelial cells in embryonic endothelium, are the primary source of multipotent hematopoietic stem cells. In this review, we discuss current status in the generation of multipotent hematopoietic stem and progenitor cells from hPSCs via hemogenic endothelial cells. We also review the achievements in direct reprogramming from non-hematopoietic cells to hematopoietic stem and progenitor cells. Further characterization of hematopoietic differentiation in hPSCs will improve our understanding of blood development and expedite the development of hPSC-derived blood products for therapeutic purpose. © 2015 Wiley Periodicals, Inc.

Circulating Endothelial-Derived Activated Microparticle: A Useful Biomarker for Predicting One-Year Mortality in Patients with Advanced Non-Small Cell Lung Cancer

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Chin-Chou Wang

2014-01-01

Full Text Available Background. This study tested the hypothesis that circulating microparticles (MPs are useful biomarkers for predicting one-year mortality in patients with end-stage non-small cell lung cancer (ES-NSCLC. Methods and Results. One hundred seven patients were prospectively enrolled into the study between April 2011 and February 2012, and each patient received regular follow-up after enrollment. Levels of four MPs in circulation, (1 platelet-derived activated MPs (PDAc-MPs, (2 platelet-derived apoptotic MPs (PDAp-MPs, (3 endothelial-derived activated MPs (EDAc-MPs, and (4 endothelial-derived apoptotic MPs (EDAp-MPs, were measured just after the patient was enrolled into the study using flow cytometry. Patients who survived for more than one year were categorized into group 1 (n=56 (one-year survivors and patients who survived less than one year were categorized into group 2 (n=51 (one-year nonsurvivors. Male gender, incidence of liver metastasis, progression of disease after first-line treatment, poor performance status, and the Charlson comorbidity index were significantly higher in group 2 than in group 1 (all P<0.05. Additionally, as measured by flow cytometry, only the circulating level of EDAc-MPs was found to be significantly higher in group 2 than in group 1 (P=0.006. Multivariate analysis demonstrated that circulating level of EDAc-MPs along with brain metastasis and male gender significantly and independently predictive of one-year mortality (all P<0.035. Conclusion. Circulating EDAc-MPs may be a useful biomarker predictive of one-year morality in ES-NSCLC patients.

Hypoxia Mediated Release of Endothelial Microparticles and Increased Association of S100A12 with Circulating Neutrophils

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Rebecca V. Vince

2009-01-01

Full Text Available Microparticles are released from the endothelium under normal homeostatic conditions and have been shown elevated in disease states, most notably those characterised by endothelial dysfunction. The endothelium is sensitive to oxidative stress/status and vascular cell adhesion molecule-1 (VCAM-1 expression is upregulated upon activated endothelium, furthermore the presence of VCAM-1 on microparticles is known. S100A12, a calcium binding protein part of the S100 family, is shown to be present on circulating leukocytes and is thought a sensitive marker to local inflammatory process, which may be driven by oxidative stress. Eight healthy males were subjected to breathing hypoxic air (15% O2, approximately equivalent to 3000 metres altitude for 80 minutes in a temperature controlled laboratory and venous blood samples were processed immediately for VCAM-1 microparticles (VCAM-1 MP and S100A12 association with leukocytes by flow cytometry. A pre-hypoxic blood sample was used for comparison. Both VCAM-1 MP and S100A12 association with neutrophils were significantly elevated post hypoxic breathing later declining to levels observed in the pre-test samples. A similar trend was observed in both cases and a correlation may exist between these two markers in response to hypoxia. These data offer evidence using novel markers of endothelial and circulating blood responses to hypoxia.

The biocompatibility of titanium cardiovascular devices seeded with autologous blood-derived endothelial progenitor cells: EPC-seeded antithrombotic Ti implants.

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Achneck, Hardean E; Jamiolkowski, Ryan M; Jantzen, Alexandra E; Haseltine, Justin M; Lane, Whitney O; Huang, Jessica K; Galinat, Lauren J; Serpe, Michael J; Lin, Fu-Hsiung; Li, Madison; Parikh, Amar; Ma, Liqiao; Chen, Tao; Sileshi, Bantayehu; Milano, Carmelo A; Wallace, Charles S; Stabler, Thomas V; Allen, Jason D; Truskey, George A; Lawson, Jeffrey H

2011-01-01

Implantable and extracorporeal cardiovascular devices are commonly made from titanium (Ti) (e.g. Ti-coated Nitinol stents and mechanical circulatory assist devices). Endothelializing the blood-contacting Ti surfaces of these devices would provide them with an antithrombogenic coating that mimics the native lining of blood vessels and the heart. We evaluated the viability and adherence of peripheral blood-derived porcine endothelial progenitor cells (EPCs), seeded onto thin Ti layers on glass slides under static conditions and after exposure to fluid shear stresses. EPCs attached and grew to confluence on Ti in serum-free medium, without preadsorption of proteins. After attachment to Ti for 15 min, less than 5% of the cells detached at a shear stress of 100 dyne / cm(2). Confluent monolayers of EPCs on smooth Ti surfaces (Rq of 10 nm), exposed to 15 or 100 dyne/cm(2) for 48 h, aligned and elongated in the direction of flow and produced nitric oxide dependent on the level of shear stress. EPC-coated Ti surfaces had dramatically reduced platelet adhesion when compared to uncoated Ti surfaces. These results indicate that peripheral blood-derived EPCs adhere and function normally on Ti surfaces. Therefore EPCs may be used to seed cardiovascular devices prior to implantation to ameliorate platelet activation and thrombus formation. Copyright © 2010 Elsevier Ltd. All rights reserved.

Open the gates: vascular neurocrine signaling mobilizes hematopoietic stem and progenitor cells.

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Itkin, Tomer; Gómez-Salinero, Jesús María; Rafii, Shahin

2017-12-01

Mobilization of hematopoietic stem and progenitor cells (HSPCs) from the bone marrow (BM) into the peripheral blood is a complex process that is enhanced dramatically under stress-induced conditions. A better understanding of how the mobilization process is regulated will likely facilitate the development of improved clinical protocols for stem cell harvesting and transplantation. In this issue of the JCI, Singh et al. (1) showed that the truncated cleaved form of neurotransmitter neuropeptide Y (NPY) actively promotes a breach of BM vascular sinusoidal portals, thereby augmenting HSPC trafficking to the circulation. The authors report a previously unrecognized axis, in which expression of the enzyme dipeptidylpeptidase-4 (DPP4)/CD26 by endothelial cells activates NPY-mediated signaling by increasing the bioavailability of the truncated form of NPY. These findings underscore the importance of and urgency to develop pharmacological therapies that target the vasculature and regulate diverse aspects of hematopoiesis, such as HSPC trafficking, in steady-state and stress-induced conditions.

Endothelial MMP14 is required for endothelial-dependent growth support of human airway basal cells

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Ding, Bi-Sen; Gomi, Kazunori; Rafii, Shahin; Crystal, Ronald G.; Walters, Matthew S.

2015-01-01

ABSTRACT Human airway basal cells are the stem (or progenitor) population of the airway epithelium, and play a central role in anchoring the epithelium to the basement membrane. The anatomic position of basal cells allows for potential paracrine signaling between them and the underlying non-epithelial stromal cells. In support of this, we have previously demonstrated that endothelial cells support growth of basal cells during co-culture through vascular endothelial growth factor A (VEGFA)-mediated signaling. Building on these findings, we found, by RNA sequencing analysis, that basal cells expressed multiple fibroblast growth factor (FGF) ligands (FGF2, FGF5, FGF11 and FGF13) and that only FGF2 and FGF5 were capable of functioning in a paracrine manner to activate classical FGF receptor (FGFR) signaling. Antibody-mediated blocking of FGFR1 during basal-cell–endothelial-cell co-culture significantly reduced the endothelial-cell-dependent basal cell growth. Stimulation of endothelial cells with basal-cell-derived growth factors induced endothelial cell expression of matrix metallopeptidase 14 (MMP14), and short hairpin RNA (shRNA)-mediated knockdown of endothelial cell MMP14 significantly reduced the endothelial-cell-dependent growth of basal cells. Overall, these data characterize a new growth-factor-mediated reciprocal ‘crosstalk’ between human airway basal cells and endothelial cells that regulates proliferation of basal cells. PMID:26116571

microRNA 126 inhibits the transition of endothelial progenitor cells to mesenchymal cells via the PIK3R2-PI3K/Akt signalling pathway.

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Zhang, Junfeng; Zhang, Zongqi; Zhang, David Y; Zhu, Jianbing; Zhang, Tiantian; Wang, Changqian

2013-01-01

Endothelial progenitor cells (EPCs) are capable of proliferating and differentiating into mature endothelial cells, and they have been considered as potential candidates for coronary heart disease therapy. However, the transition of EPCs to mesenchymal cells is not fully understood. This study aimed to explore the role of microRNA 126 (miR-126) in the endothelial-to-mesenchymal transition (EndMT) induced by transforming growth factor beta 1 (TGFβ1). EndMT of rat bone marrow-derived EPCs was induced by TGFβ1 (5 ng/mL) for 7 days. miR-126 expression was depressed in the process of EPC EndMT. The luciferase reporter assay showed that the PI3K regulatory subunit p85 beta (PIK3R2) was a direct target of miR-126 in EPCs. Overexpression of miR-126 by a lentiviral vector (lenti-miR-126) was found to downregulate the mRNA expression of mesenchymal cell markers (α-SMA, sm22-a, and myocardin) and to maintain the mRNA expression of progenitor cell markers (CD34, CD133). In the cellular process of EndMT, there was an increase in the protein expression of PIK3R2 and the nuclear transcription factors FoxO3 and Smad4; PI3K and phosphor-Akt expression decreased, a change that was reversed markedly by overexpression of miR-126. Furthermore, knockdown of PIK3R2 gene expression level showed reversed morphological changes of the EPCs treated with TGFβ1, thereby giving the evidence that PIK3R2 is the target gene of miR-126 during EndMT process. These results show that miR-126 targets PIK3R2 to inhibit EPC EndMT and that this process involves regulation of the PI3K/Akt signalling pathway. miR-126 has the potential to be used as a biomarker for the early diagnosis of intimal hyperplasia in cardiovascular disease and can even be a therapeutic tool for treating cardiovascular diseases mediated by the EndMT process.

Key endothelial cell angiogenic mechanisms are stimulated by the circulating milieu in sickle cell disease and attenuated by hydroxyurea

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Lopes, Flavia C. M.; Traina, Fabiola; Almeida, Camila B.; Leonardo, Flavia C.; Franco-Penteado, Carla F.; Garrido, Vanessa T.; Colella, Marina P.; Soares, Raquel; Olalla-Saad, Sara T.; Costa, Fernando F.; Conran, Nicola

2015-01-01

As hypoxia-induced inflammatory angiogenesis may contribute to the manifestations of sickle cell disease, we compared the angiogenic molecular profiles of plasma from sickle cell disease individuals and correlated these with in vitro endothelial cell-mediated angiogenesis-stimulating activity and in vivo neovascularization. Bioplex demonstrated that plasma from patients with steady-state sickle cell anemia contained elevated concentrations of pro-angiogenic factors (angiopoietin-1, basic fibroblast growth factor, vascular endothelial growth factor, vascular endothelial growth factor-D and placental growth factor) and displayed potent pro-angiogenic activity, significantly increasing endothelial cell proliferation, migration and capillary-like structure formation. In vivo neovascularization of Matrigel plugs was significantly greater in sickle cell disease mice than in non-sickle cell disease mice, consistent with an up-regulation of angiogenesis in the disease. In plasma from patients with hemoglobin SC disease without proliferative retinopathy, anti-angiogenic endostatin and thrombospondin-2 were significantly elevated. In contrast, plasma from hemoglobin SC individuals with proliferative retinopathy had a pro-angiogenic profile and more significant effects on endothelial cell proliferation and capillary formation than plasma from patients without retinopathy. Hydroxyurea therapy was associated with significant reductions in plasma angiogenic factors and inhibition of endothelial cell-mediated angiogenic mechanisms and neovascularization. Thus, individuals with sickle cell anemia or hemoglobin SC disease with retinopathy present a highly angiogenic circulating milieu, capable of stimulating key endothelial cell-mediated angiogenic mechanisms. Combination anti-angiogenic therapy to prevent the progression of unregulated neovascularization and associated manifestations in sickle cell disease, such as pulmonary hypertension, may be indicated; furthermore, the

Lipid lowering and HDL raising gene transfer increase endothelial progenitor cells, enhance myocardial vascularity, and improve diastolic function.

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Stephanie C Gordts

Full Text Available BACKGROUND: Hypercholesterolemia and low high density lipoprotein (HDL cholesterol contribute to coronary heart disease but little is known about their direct effects on myocardial function. Low HDL and raised non-HDL cholesterol levels carried increased risk for heart failure development in the Framingham study, independent of any association with myocardial infarction. The objective of this study was to test the hypothesis that increased endothelial progenitor cell (EPC number and function after lipid lowering or HDL raising gene transfer in C57BL/6 low density lipoprotein receptor deficient (LDLr(-/- mice may be associated with an enhanced relative vascularity in the myocardium and an improved cardiac function. METHODOLOGY/PRINCIPAL FINDINGS: Lipid lowering and HDL raising gene transfer were performed using the E1E3E4-deleted LDLr expressing adenoviral vector AdLDLr and the human apolipoprotein A-I expressing vector AdA-I, respectively. AdLDLr transfer in C57BL/6 LDLr(-/- mice resulted in a 2.0-fold (p<0.05 increase of the circulating number of EPCs and in an improvement of EPC function as assessed by ex vivo EPC migration and EPC adhesion. Capillary density and relative vascularity in the myocardium were 28% (p<0.01 and 22% (p<0.05 higher, respectively, in AdLDLr mice compared to control mice. The peak rate of isovolumetric relaxation was increased by 12% (p<0.05 and the time constant of isovolumetric relaxation was decreased by 14% (p<0.05 after AdLDLr transfer. Similarly, HDL raising gene transfer increased EPC number and function and raised both capillary density and relative vascularity in the myocardium by 24% (p<0.05. The peak rate of isovolumetric relaxation was increased by 16% (p<0.05 in AdA-I mice compared to control mice. CONCLUSIONS/SIGNIFICANCE: Both lipid lowering and HDL raising gene transfer have beneficial effects on EPC biology, relative myocardial vascularity, and diastolic function. These findings raise concerns over the

Endothelial microparticle-mediated transfer of MicroRNA-126 promotes vascular endothelial cell repair via SPRED1 and is abrogated in glucose-damaged endothelial microparticles.

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Jansen, Felix; Yang, Xiaoyan; Hoelscher, Marion; Cattelan, Arianna; Schmitz, Theresa; Proebsting, Sebastian; Wenzel, Daniela; Vosen, Sarah; Franklin, Bernardo S; Fleischmann, Bernd K; Nickenig, Georg; Werner, Nikos

2013-10-29

Repair of the endothelium after vascular injury is crucial for preserving endothelial integrity and preventing the development of vascular disease. The underlying mechanisms of endothelial cell repair are largely unknown. We sought to investigate whether endothelial microparticles (EMPs), released from apoptotic endothelial cells (ECs), influence EC repair. Systemic treatment of mice with EMPs after electric denudation of the endothelium accelerated reendothelialization in vivo. In vitro experiments revealed that EMP uptake in ECs promotes EC migration and proliferation, both critical steps in endothelial repair. To dissect the underlying mechanisms, Taqman microRNA array was performed, and microRNA (miR)-126 was identified as the predominantly expressed miR in EMPs. The following experiments demonstrated that miR-126 was transported into recipient human coronary artery endothelial cells by EMPs and functionally regulated the target protein sprouty-related, EVH1 domain-containing protein 1 (SPRED1). Knockdown of miR-126 in EMPs abrogated EMP-mediated effects on human coronary artery endothelial cell migration and proliferation in vitro and reendothelialization in vivo. Interestingly, after simulating diabetic conditions, EMPs derived from glucose-treated ECs contained significantly lower amounts of miR-126 and showed reduced endothelial repair capacity in vitro and in vivo. Finally, expression analysis of miR-126 in circulating microparticles from 176 patients with stable coronary artery disease with and without diabetes mellitus revealed a significantly reduced miR-126 expression in circulating microparticles from diabetic patients. Endothelial microparticles promote vascular endothelial repair by delivering functional miR-126 into recipient cells. In pathological hyperglycemic conditions, EMP-mediated miR-126-induced EC repair is altered.

Chemokine receptors CXCR2 and CX3CR1 differentially regulate functional responses of bone-marrow endothelial progenitors during atherosclerotic plaque regression

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Herlea-Pana, Oana; Yao, Longbiao; Heuser-Baker, Janet; Wang, Qiongxin; Wang, Qilong; Georgescu, Constantin; Zou, Ming-Hui; Barlic-Dicen, Jana

2015-01-01

Aims Atherosclerosis manifests itself as arterial plaques, which lead to heart attacks or stroke. Treatments supporting plaque regression are therefore aggressively pursued. Studies conducted in models in which hypercholesterolaemia is reversible, such as the Reversa mouse model we have employed in the current studies, will be instrumental for the development of such interventions. Using this model, we have shown that advanced atherosclerosis regression occurs when lipid lowering is used in combination with bone-marrow endothelial progenitor cell (EPC) treatment. However, it remains unclear how EPCs home to regressing plaques and how they augment atherosclerosis reversal. Here we identify molecules that support functional responses of EPCs during plaque resolution. Methods and results Chemokines CXCL1 and CX3CL1 were detected in the vascular wall of atheroregressing Reversa mice, and their cognate receptors CXCR2 and CX3CR1 were observed on adoptively transferred EPCs in circulation. We tested whether CXCL1–CXCR2 and CX3CL1–CX3CR1 axes regulate functional responses of EPCs during plaque reversal. We show that pharmacological inhibition of CXCR2 or CX3CR1, or genetic inactivation of these two chemokine receptors interfered with EPC-mediated advanced atherosclerosis regression. We also demonstrate that CXCR2 directs EPCs to regressing plaques while CX3CR1 controls a paracrine function(s) of these cells. Conclusion CXCR2 and CX3CR1 differentially regulate EPC functional responses during atheroregression. Our study improves understanding of how chemokines and chemokine receptors regulate plaque resolution, which could determine the effectiveness of interventions reducing complications of atherosclerosis. PMID:25765938

Wnt signaling positively regulates endothelial cell fate specification in the Fli1a-positive progenitor population via Lef1.

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Hübner, Kathleen; Grassme, Kathrin S; Rao, Jyoti; Wenke, Nina K; Zimmer, Cordula L; Korte, Laura; Mu Ller, Katja; Sumanas, Saulius; Greber, Boris; Herzog, Wiebke

2017-10-01

During vertebrate embryogenesis, vascular endothelial cells (ECs) and primitive erythrocytes become specified within close proximity in the posterior lateral plate mesoderm (LPM) from a common progenitor. However, the signaling cascades regulating the specification into either lineage remain largely elusive. Here, we analyze the contribution of β-catenin dependent Wnt signaling to EC and erythrocyte specification during zebrafish embryogenesis. We generated novel β-catenin dependent Wnt signaling reporters which, by using destabilized fluorophores (Venus-Pest, dGFP), specifically allow us to detect Wnt signaling responses in narrow time windows as well as in spatially restricted domains, defined by Cre recombinase expression (Tg(axin2 BAC :Venus-Pest) mu288 ; Tg(14TCF:loxP-STOP-loxP-dGFP) mu202 ). We therefore can detect β-catenin dependent Wnt signaling activity in a subset of the Fli1a-positive progenitor population. Additionally, we show that mesodermal Wnt3a-mediated signaling via the transcription factor Lef1 positively regulates EC specification (defined by kdrl expression) at the expense of primitive erythrocyte specification (defined by gata1 expression) in zebrafish embryos. Using mesoderm derived from human embryonic stem cells, we identified the same principle of Wnt signaling dependent EC specification in conjunction with auto-upregulation of LEF1. Our data indicate a novel role of β-catenin dependent Wnt signaling in regulating EC specification during vasculogenesis. Copyright © 2017. Published by Elsevier Inc.

DPP4 inhibitors promote biological functions of human endothelial progenitor cells by targeting the SDF-1/CXCR4 signaling pathway

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Liu Feng

2016-01-01

Full Text Available Dipeptidyl peptidase 4 (DPP4 inhibitors(oral hypoglycemic agentshave beneficial effects during the early stages of diabetes. In this study, we evaluated the role of DPP4inhibitorsonthe biological functions of cultured human endothelial progenitor cells (EPCs. After treating EPCs with the DPP4 inhibitors sitagliptin and vildagliptin, we examined the mRNA expression of DPP4, vascular endothelial growth factor (VEGF,VEGF receptor 2 (VEGFR-2,endothelial nitric oxide synthase (eNOS, caspase-3,stromal cell-derived factor-1 (SDF-1, chemokine (C-X-C motif receptor 4 (CXCR4 were measured by RT-PCR. The protein expression of SDF-1 and CXCR4 was determined by Western blot; cell proliferation was tested by the MTT method, and DPP4 activity was determined by a DPP4 assay. Our results revealed that DPP4 expression and activity were inhibited following the treatment with various doses of DPP4 inhibitors. Cell proliferation and the expression of VEGF, VEGFR-2andeNOS were up regulated, while cell apoptosis was inhibited by DPP4 inhibitors in a dose-dependent manner. DPP4 inhibitors activated the SDF-1/CXCR4 signaling pathway, shown by the elevated expression of SDF-1/CXCR4. This further proved that after the SDF-1/CXCR4 signaling pathway was blocked by its inhibitor ADM3100, the effects of DPP4 inhibitors on the proliferation and apoptosis, and the expression of VEGF, VEGFR-2and eNOS of EPCs were significantly reduced. These findings suggest that DPP4 inhibitors promote the biological functions of human EPCs by up regulating the SDF-1/CXCR4 signaling pathway.

Progress of stem/progenitor cell-based therapy for retinal degeneration.

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Tang, Zhimin; Zhang, Yi; Wang, Yuyao; Zhang, Dandan; Shen, Bingqiao; Luo, Min; Gu, Ping

2017-05-10

Retinal degeneration (RD), such as age-related macular degeneration (AMD) and retinitis pigmentosa, is one of the leading causes of blindness. Presently, no satisfactory therapeutic options are available for these diseases principally because the retina and retinal pigmented epithelium (RPE) do not regenerate, although wet AMD can be prevented from further progression by anti-vascular endothelial growth factor therapy. Nevertheless, stem/progenitor cell approaches exhibit enormous potential for RD treatment using strategies mainly aimed at the rescue and replacement of photoreceptors and RPE. The sources of stem/progenitor cells are classified into two broad categories in this review, which are (1) ocular-derived progenitor cells, such as retinal progenitor cells, and (2) non-ocular-derived stem cells, including embryonic stem cells, induced pluripotent stem cells, and mesenchymal stromal cells. Here, we discuss in detail the progress in the study of four predominant stem/progenitor cell types used in animal models of RD. A short overview of clinical trials involving the stem/progenitor cells is also presented. Currently, stem/progenitor cell therapies for RD still have some drawbacks such as inhibited proliferation and/or differentiation in vitro (with the exception of the RPE) and limited long-term survival and function of grafts in vivo. Despite these challenges, stem/progenitor cells represent the most promising strategy for RD treatment in the near future.

Effects of simulated altitude (normobaric hypoxia on cardiorespiratory parameters and circulating endothelial precursors in healthy subjects

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Pierini Alberto

2007-08-01

Full Text Available Abstract Background Circulating Endothelial Precursors (PB-EPCs are involved in the maintenance of the endothelial compartment being promptly mobilized after injuries of the vascular endothelium, but the effects of a brief normobaric hypoxia on PB-EPCs in healthy subjects are scarcely studied. Methods Clinical and molecular parameters were investigated in healthy subjects (n = 8 in basal conditions (T0 and after 1 h of normobaric hypoxia (T1, with Inspiratory Fraction of Oxygen set at 11.2% simulating 4850 mt of altitude. Blood samples were obtained at T0 and T1, as well as 7 days after hypoxia (T2. Results In all studied subjects we observed a prompt and significant increase in PB-EPCs, with a return to basal value at T2. The induction of hypoxia was confirmed by Alveolar Oxygen Partial Pressure (PAO2 and Spot Oxygen Saturation decreases. Heart rate increased, but arterial pressure and respiratory response were unaffected. The change in PB-EPCs percent from T0 to T1 was inversely related to PAO2 at T1. Rapid (T1 increases in serum levels of hepatocyte growth factor and erythropoietin, as well as in cellular PB-EPCs-expression of Hypoxia Inducible Factor-1α were observed. Conclusion In conclusion, the endothelial compartment seems quite responsive to standardized brief hypoxia, possibly important for PB-EPCs activation and recruitment.

EPO Receptor Gain-of-Function Causes Hereditary Polycythemia, Alters CD34+ Cell Differentiation and Increases Circulating Endothelial Precursors

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Perrotta, Silverio; Cucciolla, Valeria; Ferraro, Marcella; Ronzoni, Luisa; Tramontano, Annunziata; Rossi, Francesca; Scudieri, Anna Chiara; Borriello, Adriana; Roberti, Domenico; Nobili, Bruno; Cappellini, Maria Domenica; Oliva, Adriana; Amendola, Giovanni; Migliaccio, Anna Rita; Mancuso, Patrizia; Martin-Padura, Ines; Bertolini, Francesco; Yoon, Donghoon; Prchal, Josef T.; Della Ragione, Fulvio

2010-01-01

Background Gain-of-function of erythropoietin receptor (EPOR) mutations represent the major cause of primary hereditary polycythemia. EPOR is also found in non-erythroid tissues, although its physiological role is still undefined. Methodology/Principal Findings We describe a family with polycythemia due to a heterozygous mutation of the EPOR gene that causes a G→T change at nucleotide 1251 of exon 8. The novel EPOR G1251T mutation results in the replacement of a glutamate residue by a stop codon at amino acid 393. Differently from polycythemia vera, EPOR G1251T CD34+ cells proliferate and differentiate towards the erythroid phenotype in the presence of minimal amounts of EPO. Moreover, the affected individuals show a 20-fold increase of circulating endothelial precursors. The analysis of erythroid precursor membranes demonstrates a heretofore undescribed accumulation of the truncated EPOR, probably due to the absence of residues involved in the EPO-dependent receptor internalization and degradation. Mutated receptor expression in EPOR-negative cells results in EPOR and Stat5 phosphorylation. Moreover, patient erythroid precursors present an increased activation of EPOR and its effectors, including Stat5 and Erk1/2 pathway. Conclusions/Significance Our data provide an unanticipated mechanism for autosomal dominant inherited polycythemia due to a heterozygous EPOR mutation and suggest a regulatory role of EPO/EPOR pathway in human circulating endothelial precursors homeostasis. PMID:20700488

Circulating Endothelial Microparticles and Correlation of Serum 1,25-Dihydroxyvitamin D with Adiponectin, Nonesterified Fatty Acids, and Glycerol from Middle-Aged Men in China

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Zhongxiao Wan

2016-01-01

Full Text Available The aim of the present study is (1 to determine the correlation between circulating 1,25-dihydroxyvitamin D [25(OHD] and adiponectin, nonesterified fatty acids (NEFAs, and glycerol and (2 to determine the alterations in circulating endothelial microparticles (EMPs in Chinese male subjects with increased body mass index (BMI. A total of 45 male adults were enrolled with varied BMI [i.e., lean, overweight (OW, and obese (OB, N=15 per group]. Blood samples were collected under overnight fasting condition, and plasma was isolated for the measurement of endothelial microparticles (EMPs, total and high-molecular weight (HMW adiponectin, 25(OHD, nonesterified fatty acids (NEFAs, and glycerol. Circulating 25(OHD levels were inversely associated with total adiponectin, NEFA, and glycerol levels. There is no difference for CD62E+ or CD31+/CD42b− EMPs among 3 groups. In Chinese male adults with varied BMI, an inverse correlation existed between 25(OHD levels and total adiponectin, NEFA, and glycerol levels; and there is no significant difference for CD62E+ or CD31+/CD42b− EMPs among lean, overweight, and obese subjects.

Endothelial progenitor cells from human dental pulp-derived iPS cells as a therapeutic target for ischemic vascular diseases.

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Yoo, Chae Hwa; Na, Hee-Jun; Lee, Dong-Seol; Heo, Soon Chul; An, Yuri; Cha, Junghwa; Choi, Chulhee; Kim, Jae Ho; Park, Joo-Cheol; Cho, Yee Sook

2013-11-01

Human dental pulp cells (hDPCs) are a valuable source for the generation of patient-specific human induced pluripotent stem cells (hiPSCs). An advanced strategy for the safe and efficient reprogramming of hDPCs and subsequent lineage-specific differentiation is a critical step toward clinical application. In present research, we successfully generated hDPC-iPSCs using only two non-oncogenic factors: Oct4 and Sox2 (2F hDPC-hiPSCs) and evaluated the feasibility of hDPC-iPSCs as substrates for endothelial progenitor cells (EPCs), contributing to EPC-based therapies. Under conventional differentiation conditions, 2F hDPC-hiPSCs showed higher differentiation efficiency, compared to hiPSCs from other cell types, into multipotent CD34(+) EPCs (2F-hEPCs) capable to differentiate into functional endothelial and smooth muscle cells. The angiogenic and neovasculogenic activities of 2F-hEPCs were confirmed using a Matrigel plug assay in mice. In addition, the therapeutic effects of 2F-hEPC transplantation were confirmed in mouse models of hind-limb ischemia and myocardial infarction. Importantly, 2F-EPCs effectively integrated into newly formed vascular structures and enhanced neovascularization via likely both direct and indirect paracrine mechanisms. 2F hDPC-hiPSCs have a robust capability for the generation of angiogenic and vasculogenic EPCs, representing a strategy for patient-specific EPC therapies and disease modeling, particularly for ischemic vascular diseases. Copyright © 2013 Elsevier Ltd. All rights reserved.

Curcumin induces therapeutic angiogenesis in a diabetic mouse hindlimb ischemia model via modulating the function of endothelial progenitor cells.

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You, Jinzhi; Sun, Jiacheng; Ma, Teng; Yang, Ziying; Wang, Xu; Zhang, Zhiwei; Li, Jingjing; Wang, Longgang; Ii, Masaaki; Yang, Junjie; Shen, Zhenya

2017-08-03

Neovascularization is impaired in diabetes mellitus, which leads to the development of peripheral arterial disease and is mainly attributed to the dysfunction of endothelial progenitor cells (EPCs). Previous studies proved the promotional effect of curcumin on neovascularization in wound healing of diabetes. Thus, we hypothesize that curcumin could promote neovascularization at sites of hindlimb ischemia in diabetes and might take effect via modulating the function of EPCs. Streptozotocin-induced type 1 diabetic mice and nondiabetic mice both received unilateral hindlimb ischemic surgery. Curcumin was then administrated to the mice by lavage for 14 days consecutively. Laser Doppler perfusion imaging was conducted to demonstrate the blood flow reperfusion. Capillary density was measured in the ischemic gastrocnemius muscle. In addition, angiogenesis, migration, proliferation abilities, and senescence were determined in EPCs isolated from diabetic and nondiabetic mice. Quantitative PCR was then used to determine the mRNA expression of vascular endothelial growth factor (VEGF) and angiopoetin-1 (Ang-1) in EPCs. Curcumin application to type 1 diabetic mice significantly improved blood reperfusion and increased the capillary density in ischemic hindlimbs. The in-vitro study also revealed that the angiogenesis, migration, and proliferation abilities of EPCs and the number of senescent EPCs were reversed by curcumin application. Quantitative PCR confirmed the overexpression of VEGF-A and Ang-1 in EPCs after curcumin treatment. Curcumin could enhance neovascularization via promoting the function of EPCs in a diabetic mouse hindlimb ischemia model.

Intradialytic aerobic cycling exercise alleviates inflammation and improves endothelial progenitor cell count and bone density in hemodialysis patients.

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Liao, Min-Tser; Liu, Wen-Chih; Lin, Fu-Huang; Huang, Ching-Feng; Chen, Shao-Yuan; Liu, Chuan-Chieh; Lin, Shih-Hua; Lu, Kuo-Cheng; Wu, Chia-Chao

2016-07-01

Inflammation, endothelial dysfunction, and mineral bone disease are critical factors contributing to morbidity and mortality in hemodialysis (HD) patients. Physical exercise alleviates inflammation and increases bone density. Here, we investigated the effects of intradialytic aerobic cycling exercise on HD patients. Forty end-stage renal disease patients undergoing HD were randomly assigned to either an exercise or control group. The patients in the exercise group performed a cycling program consisting of a 5-minute warm-up, 20 minutes of cycling at the desired workload, and a 5-minute cool down during 3 HD sessions per week for 3 months. Biochemical markers, inflammatory cytokines, nutritional status, the serum endothelial progenitor cell (EPC) count, bone mineral density, and functional capacity were analyzed. After 3 months of exercise, the patients in the exercise group showed significant improvements in serum albumin levels, the body mass index, inflammatory cytokine levels, and the number of cells positive for CD133, CD34, and kinase insert domain-conjugating receptor. Compared with the exercise group, the patients in the control group showed a loss of bone density at the femoral neck and no increases in EPCs. The patients in the exercise group also had a significantly greater 6-minute walk distance after completing the exercise program. Furthermore, the number of EPCs significantly correlated with the 6-minute walk distance both before and after the 3-month program. Intradialytic aerobic cycling exercise programs can effectively alleviate inflammation and improve nutrition, bone mineral density, and exercise tolerance in HD patients.

Effect of β-nerve growth factor on differentiation of endothelial ...

African Journals Online (AJOL)

(Ad-EGFP-hβ-NGF) on the differentiation of endothelial progenitor cells (EPCs) in rats. Methods: The successfully ... may contribute to angiopoiesis or vascular repair. Keywords: β-Nerve ... angiogenesis in damaged tissues [6]. In this study ...

Insights into the molecular mechanisms of diabetes-induced endothelial dysfunction

DEFF Research Database (Denmark)

Saad, Mohamed I.; Abdelkhalek, Taha M.; Saleh, Moustafa M.

2015-01-01

-associated metabolic disturbances (IR, subclinical inflammation, dyslipidemia, hyperglycemia, dysregulated production of adipokines, defective incretin and gut hormones production/action, and oxidative stress) and ED, focusing on oxidative stress and endothelial progenitor cells (EPCs). In addition, we re...

Hmga2 regulates self-renewal of retinal progenitors.

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Parameswaran, Sowmya; Xia, Xiaohuan; Hegde, Ganapati; Ahmad, Iqbal

2014-11-01

In vertebrate retina, histogenesis occurs over an extended period. To sustain the temporal generation of diverse cell types, retinal progenitor cells (RPCs) must self-renew. However, self-renewal and regulation of RPCs remain poorly understood. Here, we demonstrate that cell-extrinsic factors coordinate with the epigenetic regulator high-mobility group AT-hook 2 (Hmga2) to regulate self-renewal of late retinal progenitor cells (RPCs). We observed that a small subset of RPCs was capable of clonal propagation and retained multipotentiality of parents in the presence of endothelial cells (ECs), known self-renewal regulators in various stem cell niches. The self-renewing effects, also observed in vivo, involve multiple intercellular signaling pathways, engaging Hmga2. As progenitors exhaust during retinal development, expression of Hmga2 progressively decreases. Analyses of Hmga2-expression perturbation, in vitro and in vivo, revealed that Hmga2 functionally helps to mediate cell-extrinsic influences on late-retinal progenitor self-renewal. Our results provide a framework for integrating the diverse intercellular influences elicited by epigenetic regulators for self-renewal in a dynamic stem cell niche: the developing vertebrate retina. © 2014. Published by The Company of Biologists Ltd.

Preterm Cord Blood Contains a Higher Proportion of Immature Hematopoietic Progenitors Compared to Term Samples.

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Podestà, Marina; Bruschettini, Matteo; Cossu, Claudia; Sabatini, Federica; Dagnino, Monica; Romantsik, Olga; Spaggiari, Grazia Maria; Ramenghi, Luca Antonio; Frassoni, Francesco

2015-01-01

Cord blood contains high number of hematopoietic cells that after birth disappear. In this paper we have studied the functional properties of the umbilical cord blood progenitor cells collected from term and preterm neonates to establish whether quantitative and/or qualitative differences exist between the two groups. Our results indicate that the percentage of total CD34+ cells was significantly higher in preterm infants compared to full term: 0.61% (range 0.15-4.8) vs 0.3% (0.032-2.23) p = 0.0001 and in neonates <32 weeks of gestational age (GA) compared to those ≥32 wks GA: 0.95% (range 0.18-4.8) and 0.36% (0.15-3.2) respectively p = 0.0025. The majority of CD34+ cells co-expressed CD71 antigen (p<0.05 preterm vs term) and grew in vitro large BFU-E, mostly in the second generation. The subpopulations CD34+CD38- and CD34+CD45- resulted more represented in preterm samples compared to term, conversely, Side Population (SP) did not show any difference between the two group. The absolute number of preterm colonies (CFCs/10microL) resulted higher compared to term (p = 0.004) and these progenitors were able to grow until the third generation maintaining an higher proportion of CD34+ cells (p = 0.0017). The number of colony also inversely correlated with the gestational age (Pearson r = -0.3001 p<0.0168). We found no differences in the isolation and expansion capacity of Endothelial Colony Forming Cells (ECFCs) from cord blood of term and preterm neonates: both groups grew in vitro large number of endothelial cells until the third generation and showed a transitional phenotype between mesenchymal stem cells and endothelial progenitors (CD73, CD31, CD34 and CD144)The presence, in the cord blood of preterm babies, of high number of immature hematopoietic progenitors and endothelial/mesenchymal stem cells with high proliferative potential makes this tissue an important source of cells for developing new cells therapies.

Preterm Cord Blood Contains a Higher Proportion of Immature Hematopoietic Progenitors Compared to Term Samples.

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Marina Podestà

Full Text Available Cord blood contains high number of hematopoietic cells that after birth disappear. In this paper we have studied the functional properties of the umbilical cord blood progenitor cells collected from term and preterm neonates to establish whether quantitative and/or qualitative differences exist between the two groups.Our results indicate that the percentage of total CD34+ cells was significantly higher in preterm infants compared to full term: 0.61% (range 0.15-4.8 vs 0.3% (0.032-2.23 p = 0.0001 and in neonates <32 weeks of gestational age (GA compared to those ≥32 wks GA: 0.95% (range 0.18-4.8 and 0.36% (0.15-3.2 respectively p = 0.0025. The majority of CD34+ cells co-expressed CD71 antigen (p<0.05 preterm vs term and grew in vitro large BFU-E, mostly in the second generation. The subpopulations CD34+CD38- and CD34+CD45- resulted more represented in preterm samples compared to term, conversely, Side Population (SP did not show any difference between the two group. The absolute number of preterm colonies (CFCs/10microL resulted higher compared to term (p = 0.004 and these progenitors were able to grow until the third generation maintaining an higher proportion of CD34+ cells (p = 0.0017. The number of colony also inversely correlated with the gestational age (Pearson r = -0.3001 p<0.0168.We found no differences in the isolation and expansion capacity of Endothelial Colony Forming Cells (ECFCs from cord blood of term and preterm neonates: both groups grew in vitro large number of endothelial cells until the third generation and showed a transitional phenotype between mesenchymal stem cells and endothelial progenitors (CD73, CD31, CD34 and CD144The presence, in the cord blood of preterm babies, of high number of immature hematopoietic progenitors and endothelial/mesenchymal stem cells with high proliferative potential makes this tissue an important source of cells for developing new cells therapies.

microRNA 126 inhibits the transition of endothelial progenitor cells to mesenchymal cells via the PIK3R2-PI3K/Akt signalling pathway.

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Junfeng Zhang

Full Text Available AIMS: Endothelial progenitor cells (EPCs are capable of proliferating and differentiating into mature endothelial cells, and they have been considered as potential candidates for coronary heart disease therapy. However, the transition of EPCs to mesenchymal cells is not fully understood. This study aimed to explore the role of microRNA 126 (miR-126 in the endothelial-to-mesenchymal transition (EndMT induced by transforming growth factor beta 1 (TGFβ1. METHODS AND RESULTS: EndMT of rat bone marrow-derived EPCs was induced by TGFβ1 (5 ng/mL for 7 days. miR-126 expression was depressed in the process of EPC EndMT. The luciferase reporter assay showed that the PI3K regulatory subunit p85 beta (PIK3R2 was a direct target of miR-126 in EPCs. Overexpression of miR-126 by a lentiviral vector (lenti-miR-126 was found to downregulate the mRNA expression of mesenchymal cell markers (α-SMA, sm22-a, and myocardin and to maintain the mRNA expression of progenitor cell markers (CD34, CD133. In the cellular process of EndMT, there was an increase in the protein expression of PIK3R2 and the nuclear transcription factors FoxO3 and Smad4; PI3K and phosphor-Akt expression decreased, a change that was reversed markedly by overexpression of miR-126. Furthermore, knockdown of PIK3R2 gene expression level showed reversed morphological changes of the EPCs treated with TGFβ1, thereby giving the evidence that PIK3R2 is the target gene of miR-126 during EndMT process. CONCLUSIONS: These results show that miR-126 targets PIK3R2 to inhibit EPC EndMT and that this process involves regulation of the PI3K/Akt signalling pathway. miR-126 has the potential to be used as a biomarker for the early diagnosis of intimal hyperplasia in cardiovascular disease and can even be a therapeutic tool for treating cardiovascular diseases mediated by the EndMT process.

Expression of a retinoic acid signature in circulating CD34 cells from coronary artery disease patients

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van der Laan Anja M

2010-06-01

Full Text Available Abstract Background Circulating CD34+ progenitor cells have the potential to differentiate into a variety of cells, including endothelial cells. Knowledge is still scarce about the transcriptional programs used by CD34+ cells from peripheral blood, and how these are affected in coronary artery disease (CAD patients. Results We performed a whole genome transcriptome analysis of CD34+ cells, CD4+ T cells, CD14+ monocytes, and macrophages from 12 patients with CAD and 11 matched controls. CD34+ cells, compared to other mononuclear cells from the same individuals, showed high levels of KRAB box transcription factors, known to be involved in gene silencing. This correlated with high expression levels in CD34+ cells for the progenitor markers HOXA5 and HOXA9, which are known to control expression of KRAB factor genes. The comparison of expression profiles of CD34+ cells from CAD patients and controls revealed a less naïve phenotype in patients' CD34+ cells, with increased expression of genes from the Mitogen Activated Kinase network and a lowered expression of a panel of histone genes, reaching levels comparable to that in more differentiated circulating cells. Furthermore, we observed a reduced expression of several genes involved in CXCR4-signaling and migration to SDF1/CXCL12. Conclusions The altered gene expression profile of CD34+ cells in CAD patients was related to activation/differentiation by a retinoic acid-induced differentiation program. These results suggest that circulating CD34+ cells in CAD patients are programmed by retinoic acid, leading to a reduced capacity to migrate to ischemic tissues.

Comparative analysis of circulating endothelial progenitor cells in age-related macular degeneration patients using automated rare cell analysis (ARCA and fluorescence activated cell sorting (FACS.

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Emil Anthony T Say

Full Text Available BACKGROUND: Patients with age-related macular degeneration (ARMD begin with non-neovascular (NNV phenotypes usually associated with good vision. Approximately 20% of NNV-ARMD patients will convert to vision debilitating neovascular (NV ARMD, but precise timing of this event is unknown. Developing a clinical test predicting impending conversion to NV-ARMD is necessary to prevent vision loss. Endothelial progenitor cells (EPCs, defined as CD34(+VEGR2(+ using traditional fluorescence activated cell sorting (FACS, are rare cell populations known to be elevated in patients with NV-ARMD compared to NNV-ARMD. FACS has high inter-observer variability and subjectivity when measuring rare cell populations precluding development into a diagnostic test. We hypothesized that automated rare cell analysis (ARCA, a validated and FDA-approved technology for reproducible rare cell identification, can enumerate EPCs in ARMD patients more reliably. This pilot study serves as the first step in developing methods for reproducibly predicting ARMD phenotype conversion. METHODS: We obtained peripheral venous blood samples in 23 subjects with NNV-ARMD or treatment naïve NV-ARMD. Strict criteria were used to exclude subjects with known angiogenic diseases to minimize confounding results. Blood samples were analyzed in masked fashion in two separate laboratories. EPCs were independently enumerated using ARCA and FACS within 24 hours of blood sample collection, and p<0.2 was considered indicative of a trend for this proof of concept study, while statistical significance was established at 0.05. RESULTS: We measured levels of CD34(+VEGFR2(+ EPCs suggestive of a trend with higher values in patients with NV compared to NNV-ARMD (p = 0.17 using ARCA. Interestingly, CD34(+VEGR2(+ EPC analysis using FACS did not produce similar results (p = 0.94. CONCLUSIONS: CD34(+VEGR2(+ may have predictive value for EPC enumeration in future ARCA studies. EPC measurements in a small sample

Comparative analysis of circulating endothelial progenitor cells in age-related macular degeneration patients using automated rare cell analysis (ARCA) and fluorescence activated cell sorting (FACS).

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Say, Emil Anthony T; Melamud, Alex; Esserman, Denise Ann; Povsic, Thomas J; Chavala, Sai H

2013-01-01

Patients with age-related macular degeneration (ARMD) begin with non-neovascular (NNV) phenotypes usually associated with good vision. Approximately 20% of NNV-ARMD patients will convert to vision debilitating neovascular (NV) ARMD, but precise timing of this event is unknown. Developing a clinical test predicting impending conversion to NV-ARMD is necessary to prevent vision loss. Endothelial progenitor cells (EPCs), defined as CD34(+)VEGR2(+) using traditional fluorescence activated cell sorting (FACS), are rare cell populations known to be elevated in patients with NV-ARMD compared to NNV-ARMD. FACS has high inter-observer variability and subjectivity when measuring rare cell populations precluding development into a diagnostic test. We hypothesized that automated rare cell analysis (ARCA), a validated and FDA-approved technology for reproducible rare cell identification, can enumerate EPCs in ARMD patients more reliably. This pilot study serves as the first step in developing methods for reproducibly predicting ARMD phenotype conversion. We obtained peripheral venous blood samples in 23 subjects with NNV-ARMD or treatment naïve NV-ARMD. Strict criteria were used to exclude subjects with known angiogenic diseases to minimize confounding results. Blood samples were analyzed in masked fashion in two separate laboratories. EPCs were independently enumerated using ARCA and FACS within 24 hours of blood sample collection, and ptrend for this proof of concept study, while statistical significance was established at 0.05. We measured levels of CD34(+)VEGFR2(+) EPCs suggestive of a trend with higher values in patients with NV compared to NNV-ARMD (p = 0.17) using ARCA. Interestingly, CD34(+)VEGR2(+) EPC analysis using FACS did not produce similar results (p = 0.94). CD34(+)VEGR2(+) may have predictive value for EPC enumeration in future ARCA studies. EPC measurements in a small sample size were suggestive of a trend in ARMD using ARCA but not FACS. ARCA could be a

Endothelial Cells Promote Expansion of Long‐Term Engrafting Marrow Hematopoietic Stem and Progenitor Cells in Primates

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Gori, Jennifer L.; Butler, Jason M.; Kunar, Balvir; Poulos, Michael G.; Ginsberg, Michael; Nolan, Daniel J.; Norgaard, Zachary K.; Adair, Jennifer E.; Rafii, Shahin

2016-01-01

Abstract Successful expansion of bone marrow (BM) hematopoietic stem and progenitor cells (HSPCs) would benefit many HSPC transplantation and gene therapy/editing applications. However, current expansion technologies have been limited by a loss of multipotency and self‐renewal properties ex vivo. We hypothesized that an ex vivo vascular niche would provide prohematopoietic signals to expand HSPCs while maintaining multipotency and self‐renewal. To test this hypothesis, BM autologous CD34+ cells were expanded in endothelial cell (EC) coculture and transplanted in nonhuman primates. CD34+C38− HSPCs cocultured with ECs expanded up to 17‐fold, with a significant increase in hematopoietic colony‐forming activity compared with cells cultured with cytokines alone (colony‐forming unit‐granulocyte‐erythroid‐macrophage‐monocyte; p < .005). BM CD34+ cells that were transduced with green fluorescent protein lentivirus vector and expanded on ECs engrafted long term with multilineage polyclonal reconstitution. Gene marking was observed in granulocytes, lymphocytes, platelets, and erythrocytes. Whole transcriptome analysis indicated that EC coculture altered the expression profile of 75 genes in the BM CD34+ cells without impeding the long‐term engraftment potential. These findings show that an ex vivo vascular niche is an effective platform for expansion of adult BM HSPCs. Stem Cells Translational Medicine 2017;6:864–876 PMID:28297579

Genetic engineering with endothelial nitric oxide synthase improves functional properties of endothelial progenitor cells from patients with coronary artery disease: an in vitro study.

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Kaur, Savneet; Kumar, T R Santhosh; Uruno, Akira; Sugawara, Akira; Jayakumar, Karunakaran; Kartha, Chandrasekharan Cheranellore

2009-11-01

Recent studies have reported a marked impairment in the number and functions of endothelial progenitor cells (EPCs) in patients with coronary artery disease (CAD). In view of an important role of eNOS in angiogenesis, in the present study, we evaluated the effects of eNOS gene transfer in ex vivo expanded EPCs isolated from patients with CAD. The expanded EPCs were transfected with mammalian expression vector pcDNA3.1-eNOS containing the full-length human eNOS gene using lipofectamine. About 35-40% of the eNOS-EPCs had higher expression of eNOS as compared to untransfected EPCs. EPCs transfected with pcDNA3.0-EGFP, the plasmid vector expressing green fluorescent protein (GFP) were used as control. The untransfected, GFP-transfected and eNOS-transfected EPCs were compared in terms of important functional attributes of angiogenesis such as proliferation, migration, differentiation and adhesion/integration into tube-like structures in vitro. Functional studies revealed that in the presence of defined growth conditions, compared to the untransfected and GFP-transfected cells, eNOS-EPCs from patients with CAD have a significant increase in [3H] thymidine-labeled DNA (P < 0.01), migration (14.6 +/- 1.8 and 16.5 +/- 1.9 vs. 23.5 +/- 3.4 cells/field, P < 0.01), ability to differentiate into endothelial-like spindle-shaped cells (46 +/- 4.5 and 56.5 +/- 2.1 vs. 93.2 +/- 6.6 cells/field, P < 0.001) and also incorporation into tube-like structures on the matrigel (GFP-EPCs: 21.25 +/- 2.9 vs. GFP-eNOS-EPCs: 34.5 +/- 5.5 cells/field, P < 0.05). We conclude that eNOS gene transfection is a valuable approach to augment angiogenic properties of ex vivo expanded EPCs and eNOS-modified EPCs may offer significant advantages than EPCs alone in terms of their clinical use in patients with myocardial ischemia.

Dysregulation of endothelial colony-forming cell function by a negative feedback loop of circulating miR-146a and -146b in cardiovascular disease patients.

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Ting-Yu Chang

Full Text Available Functional impairment of endothelial colony-forming cells (ECFCs, a specific cell lineage of endothelial progenitor cells (EPCs is highly associated with the severity of coronary artery disease (CAD, the most common type of cardiovascular disease (CVD. Emerging evidence show that circulating microRNAs (miRNAs in CAD patients' body fluid hold a great potential as biomarkers. However, our knowledge of the role of circulating miRNA in regulating the function of ECFCs and the progression of CAD is still in its infancy. We showed that when ECFCs from healthy volunteers were incubated with conditioned medium or purified exosomes of cultured CAD ECFCs, the secretory factors from CAD ECFCs dysregulated migration and tube formation ability of healthy ECFCs. It is known that exosomes influence the physiology of recipient cells by introducing RNAs including miRNAs. By using small RNA sequencing (smRNA-seq, we deciphered the circulating miRNome in the plasma of healthy individual and CAD patients, and found that the plasma miRNA spectrum from CAD patients was significantly different from that of healthy control. Interestingly, smRNA-seq of both healthy and CAD ECFCs showed that twelve miRNAs that had a higher expression in the plasma of CAD patients also showed higher expression in CAD ECFCs when compared with healthy control. This result suggests that these miRNAs may be involved in the regulation of ECFC functions. For identification of potential mRNA targets of the differentially expressed miRNA in CAD patients, cDNA microarray analysis was performed to identify the angiogenesis-related genes that were down-regulated in CAD ECFCs and Pearson's correlation were used to identify miRNAs that were negatively correlated with the identified angiogenesis-related genes. RT-qPCR analysis of the five miRNAs that negatively correlated with the down-regulated angiogenesis-related genes in plasma and ECFC of CAD patients showed miR-146a-5p and miR-146b-5p up

Umbilical Cord Blood-Derived Mononuclear Cells Exhibit Pericyte-Like Phenotype and Support Network Formation of Endothelial Progenitor Cells In Vitro.

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Peters, Erica B; Liu, Betty; Christoforou, Nicolas; West, Jennifer L; Truskey, George A

2015-10-01

Umbilical cord blood represents a promising cell source for pro-angiogenic therapies. The present study examined the potential of mononuclear cells (MNCs) from umbilical cord blood to support endothelial progenitor cell (EPC) microvessel formation. MNCs were isolated from the cord blood of 20 separate donors and selected for further characterization based upon their proliferation potential and morphological resemblance to human vascular pericytes (HVPs). MNCs were screened for their ability to support EPC network formation using an in vitro assay (Matrigel™) as well as a reductionist, coculture system consisting of no additional angiogenic cytokines beyond those present in serum. In less than 15% of the isolations, we identified a population of highly proliferative MNCs that phenotypically resembled HVPs as assessed by expression of PDGFR-β, NG2, α-SMA, and ephrin-B2. Within a Matrigel™ system, MNCs demonstrated pericyte-like function through colocalization to EPC networks and similar effects as HVPs upon total EPC tubule length (p = 0.95) and number of branch points (p = 0.93). In a reductionist coculture system, MNCs served as pro-angiogenic mural cells by supporting EPC network formation to a significantly greater extent than HVP cocultures, by day 14 of coculture, as evidenced through EPC total tubule length (p < 0.0001) and number of branch points (p < 0.0001). Our findings are significant as we demonstrate mural cell progenitors can be isolated from umbilical cord blood and develop culture conditions to support their use in microvascular tissue engineering applications.

Macrophages control vascular stem/progenitor cell plasticity through tumor necrosis factor-α-mediated nuclear factor-κB activation.

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Wong, Mei Mei; Chen, Yikuan; Margariti, Andriani; Winkler, Bernhard; Campagnolo, Paola; Potter, Claire; Hu, Yanhua; Xu, Qingbo

2014-03-01

Vascular lineage differentiation of stem/progenitor cells can contribute to both tissue repair and exacerbation of vascular diseases such as in vein grafts. The role of macrophages in controlling vascular progenitor differentiation is largely unknown and may play an important role in graft development. This study aims to identify the role of macrophages in vascular stem/progenitor cell differentiation and thereafter elucidate the mechanisms that are involved in the macrophage- mediated process. We provide in vitro evidence that macrophages can induce endothelial cell (EC) differentiation of the stem/progenitor cells while simultaneously inhibiting their smooth muscle cell differentiation. Mechanistically, both effects were mediated by macrophage-derived tumor necrosis factor-α (TNF-α) via TNF-α receptor 1 and canonical nuclear factor-κB activation. Although the overexpression of p65 enhanced EC (or attenuated smooth muscle cell) differentiation, p65 or TNF-α receptor 1 knockdown using lentiviral short hairpin RNA inhibited EC (or rescued smooth muscle cell) differentiation in response to TNF-α. Furthermore, TNF-α-mediated EC differentiation was driven by direct binding of nuclear factor-κB (p65) to specific VE-cadherin promoter sequences. Subsequent experiments using an ex vivo decellularized vessel scaffold confirmed an increase in the number of ECs and reduction in smooth muscle cell marker expression in the presence of TNF-α. The lack of TNF-α in a knockout mouse model of vein graft decreased endothelialization and significantly increased thrombosis formation. Our study highlights the role of macrophages in directing vascular stem/progenitor cell lineage commitment through TNF-α-mediated TNF-α receptor 1 and nuclear factor-κB activation that is likely required for endothelial repair in vascular diseases such as vein graft.

The Transcription Factor Nrf2 Protects Angiogenic Capacity of Endothelial Colony-Forming Cells in High-Oxygen Radical Stress Conditions

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Gremmels, Hendrik; De Jong, Olivier G.; Hazenbrink, Diënty H.; Fledderus, Joost O.; Verhaar, Marianne C.

2017-01-01

Background. Endothelial colony forming cells (ECFCs) have shown a promise in tissue engineering of vascular constructs, where they act as endothelial progenitor cells. After implantation, ECFCs are likely to be subjected to elevated reactive oxygen species (ROS). The transcription factor Nrf2

Mechanisms of Endothelial Dysfunction in Hypertensive Pregnancy and Preeclampsia

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Possomato-Vieira, José S.; Khalil, Raouf A.

2016-01-01

Preeclampsia is a pregnancy-related disorder characterized by hypertension, and could lead to maternal and fetal morbidity and mortality. Although the causative factors and pathophysiological mechanisms are unclear, endothelial dysfunction is a major hallmark of preeclampsia. Clinical tests and experimental research have suggested that generalized endotheliosis in the systemic, renal, cerebral and hepatic circulation could decrease endothelium-derived vasodilators such as nitric oxide, prostacyclin and hyperpolarization factor and increase vasoconstrictors such as endothelin-1 and thromboxane A2, leading to increased vasoconstriction, hypertension and other manifestation of preeclampsia. In search for the upstream mechanisms that could cause endothelial dysfunction, certain genetic, demographic and environmental risk factors have been suggested to cause abnormal expression of uteroplacental integrins, cytokines and matrix metalloproteinases, leading to decreased maternal tolerance, apoptosis of invasive trophoblast cells, inadequate spiral arteries remodeling, reduced uterine perfusion pressure (RUPP), and placental ischemia/hypoxia. RUPP may cause imbalance between the anti-angiogenic factors soluble fms-like tyrosine kinase-1 and soluble endoglin and the pro-angiogenic factors vascular endothelial growth factor and placental growth factor, or stimulate the release of other circulating bioactive factors such as inflammatory cytokines, hypoxia-inducible factor-1, reactive oxygen species, and angiotensin AT1 receptor agonistic autoantibodies. These circulating factors could then target endothelial cells and cause generalized endothelial dysfunction. Therapeutic options are currently limited, but understanding the factors involved in endothelial dysfunction could help design new approaches for prediction and management of preeclampsia. PMID:27451103

Activated Fps/Fes partially rescues the in vivo developmental potential of Flk1-deficient vascular progenitor cells.

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Haigh, Jody J; Ema, Masatsugu; Haigh, Katharina; Gertsenstein, Marina; Greer, Peter; Rossant, Janet; Nagy, Andras; Wagner, Erwin F

2004-02-01

Relatively little is known about the modulators of the vascular endothelial growth factor A (VEGF-A)/Flk1 signaling cascade. To functionally characterize this pathway, VEGF-A stimulation of endothelial cells was performed. VEGF-A-mediated Flk1 activation resulted in increased translocation of the endogenous Fps/Fes cytoplasmic tyrosine kinase to the plasma membrane and increased tyrosine phosphorylation, suggesting a role for Fps/Fes in VEGF-A/Flk1 signaling events. Addition of a myristoylation consensus sequence to Fps/Fes resulted in VEGF-A-independent membrane localization of Fps/Fes in endothelial cells. Expression of the activated Fps/Fes protein in Flk1-deficient embryonic stem (ES) cells rescued their contribution to the developing vascular endothelium in vivo by using ES cell-derived chimeras. Activated Fps/Fes contributed to this rescue event by restoring the migratory potential to Flk1 null progenitors, which is required for movement of hemangioblasts from the primitive streak region into the yolk sac proper. Activated Fps/Fes in the presence of Flk1 increased the number of hemangioblast colonies in vitro and increased the number of mesodermal progenitors in vivo. These results suggest that Fps/Fes may act synergistically with Flk1 to modulate hemangioblast differentiation into the endothelium. We have also demonstrated that activated Fps/Fes causes hemangioma formation in vivo, independently of Flk1, as a result of increasing vascular progenitor density.

Paracrine effects and heterogeneity of marrow-derived stem/progenitor cells: relevance for the treatment of respiratory diseases.

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Conese, Massimo; Carbone, Annalucia; Castellani, Stefano; Di Gioia, Sante

2013-01-01

Stem cell-based treatment may represent a hope for the treatment of acute lung injury and pulmonary fibrosis, and other chronic lung diseases, such as cystic fibrosis, asthma and chronic obstructive pulmonary disease (COPD). It is well established in preclinical models that bone marrow-derived stem and progenitor cells exert beneficial effects on inflammation, immune responses and repairing of damage in virtually all lung-borne diseases. While it was initially thought that the positive outcome was due to a direct engraftment of these cells into the lung as endothelial and epithelial cells, paracrine factors are now considered the main mechanism through which stem and progenitor cells exert their therapeutic effect. This knowledge has led to the clinical use of marrow cells in pulmonary hypertension with endothelial progenitor cells (EPCs) and in COPD with mesenchymal stromal (stem) cells (MSCs). Bone marrow-derived stem cells, including hematopoietic stem/progenitor cells, MSCs, EPCs and fibrocytes, encompass a wide array of cell subsets with different capacities of engraftment and injured tissue-regenerating potential. The characterization/isolation of the stem cell subpopulations represents a major challenge to improve the efficacy of transplantation protocols used in regenerative medicine and applied to lung disorders. Copyright © 2013 S. Karger AG, Basel.

Use of autologous blood-derived endothelial progenitor cells at point-of-care to protect against implant thrombosis in a large animal model.

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Jantzen, Alexandra E; Lane, Whitney O; Gage, Shawn M; Jamiolkowski, Ryan M; Haseltine, Justin M; Galinat, Lauren J; Lin, Fu-Hsiung; Lawson, Jeffrey H; Truskey, George A; Achneck, Hardean E

2011-11-01

Titanium (Ti) is commonly utilized in many cardiovascular devices, e.g. as a component of Nitinol stents, intra- and extracorporeal mechanical circulatory assist devices, but is associated with the risk of thromboemboli formation. We propose to solve this problem by lining the Ti blood-contacting surfaces with autologous peripheral blood-derived late outgrowth endothelial progenitor cells (EPCs) after having previously demonstrated that these EPCs adhere to and grow on Ti under physiological shear stresses and functionally adapt to their environment under flow conditions ex vivo. Autologous fluorescently-labeled porcine EPCs were seeded at the point-of-care in the operating room onto Ti tubes for 30 min and implanted into the pro-thrombotic environment of the inferior vena cava of swine (n = 8). After 3 days, Ti tubes were explanted, disassembled, and the blood-contacting surface was imaged. A blinded analysis found all 4 cell-seeded implants to be free of clot, whereas 4 controls without EPCs were either entirely occluded or partially thrombosed. Pre-labeled EPCs had spread and were present on all 4 cell-seeded implants while no endothelial cells were observed on control implants. These results suggest that late outgrowth autologous EPCs represent a promising source of lining Ti implants to reduce thrombosis in vivo. Copyright © 2011 Elsevier Ltd. All rights reserved.

Synergistic actions of hematopoietic and mesenchymal stem/progenitor cells in vascularizing bioengineered tissues.

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Eduardo K Moioli

Full Text Available Poor angiogenesis is a major road block for tissue repair. The regeneration of virtually all tissues is limited by angiogenesis, given the diffusion of nutrients, oxygen, and waste products is limited to a few hundred micrometers. We postulated that co-transplantation of hematopoietic and mesenchymal stem/progenitor cells improves angiogenesis of tissue repair and hence the outcome of regeneration. In this study, we tested this hypothesis by using bone as a model whose regeneration is impaired unless it is vascularized. Hematopoietic stem/progenitor cells (HSCs and mesenchymal stem/progenitor cells (MSCs were isolated from each of three healthy human bone marrow samples and reconstituted in a porous scaffold. MSCs were seeded in micropores of 3D calcium phosphate (CP scaffolds, followed by infusion of gel-suspended CD34(+ hematopoietic cells. Co-transplantation of CD34(+ HSCs and CD34(- MSCs in microporous CP scaffolds subcutaneously in the dorsum of immunocompromised mice yielded vascularized tissue. The average vascular number of co-transplanted CD34(+ and MSC scaffolds was substantially greater than MSC transplantation alone. Human osteocalcin was expressed in the micropores of CP scaffolds and was significantly increased upon co-transplantation of MSCs and CD34(+ cells. Human nuclear staining revealed the engraftment of transplanted human cells in vascular endothelium upon co-transplantation of MSCs and CD34(+ cells. Based on additional in vitro results of endothelial differentiation of CD34(+ cells by vascular endothelial growth factor (VEGF, we adsorbed VEGF with co-transplanted CD34(+ and MSCs in the microporous CP scaffolds in vivo, and discovered that vascular number and diameter further increased, likely owing to the promotion of endothelial differentiation of CD34(+ cells by VEGF. Together, co-transplantation of hematopoietic and mesenchymal stem/progenitor cells may improve the regeneration of vascular dependent tissues such as bone

Visualisation of axolotl blastema cells and pig endothelial progenitor cells using very small super paramagnetic iron oxide particles in MRI: A technique with applications for non invasive visualisation of regenerative processes

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Lauridsen, Henrik; Kjær, N.B.; Bek, Maria

oxide particles (VSOP) in animal cells enable non invasive cell tracking using magnetic resonance imaging (MRI) and can prove useful, when visualising regenerative processes. This study examines the possibility of labelling limited numbers of axolotl blastema cells (aBC) and pig endothelial progenitor...... implanted in live axolotl tail and dead porcine heart, respectively. Cellular iron uptake was determined using inductively coupled plasma optical emission spectrometry (ICP-OES). Results: T2*-weighted 2D gradient-echo sequences on samples of 10˄5 cells yielded at significant linear correlations between...

Differential Effects of Leptin and Adiponectin in Endothelial Angiogenesis

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Raghu Adya

2015-01-01

Full Text Available Obesity is a major health burden with an increased risk of cardiovascular morbidity and mortality. Endothelial dysfunction is pivotal to the development of cardiovascular disease (CVD. In relation to this, adipose tissue secreted factors termed “adipokines” have been reported to modulate endothelial dysfunction. In this review, we focus on two of the most abundant circulating adipokines, that is, leptin and adiponectin, in the development of endothelial dysfunction. Leptin has been documented to influence a multitude of organ systems, that is, central nervous system (appetite regulation, satiety factor and cardiovascular system (endothelial dysfunction leading to atherosclerosis. Adiponectin, circulating at a much higher concentration, exists in different molecular weight forms, essentially made up of the collagenous fraction and a globular domain, the latter being investigated minimally for its involvement in proinflammatory processes including activation of NF-κβ and endothelial adhesion molecules. The opposing actions of the two forms of adiponectin in endothelial cells have been recently demonstrated. Additionally, a local and systemic change to multimeric forms of adiponectin has gained importance. Thus detailed investigations on the potential interplay between these adipokines would likely result in better understanding of the missing links connecting CVD, adipokines, and obesity.

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Indian Academy of Sciences (India)

2016-08-02

Aug 2, 2016 ... healing, repairing injured tissues and to fight infections. Copper is generally ..... ciated right now and the role of other chaperones has to be explored. .... depletion decreases circulating endothelial progenitor cells in women.

Endothelial Cells Promote Expansion of Long-Term Engrafting Marrow Hematopoietic Stem and Progenitor Cells in Primates.

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Gori, Jennifer L; Butler, Jason M; Kunar, Balvir; Poulos, Michael G; Ginsberg, Michael; Nolan, Daniel J; Norgaard, Zachary K; Adair, Jennifer E; Rafii, Shahin; Kiem, Hans-Peter

2017-03-01

Successful expansion of bone marrow (BM) hematopoietic stem and progenitor cells (HSPCs) would benefit many HSPC transplantation and gene therapy/editing applications. However, current expansion technologies have been limited by a loss of multipotency and self-renewal properties ex vivo. We hypothesized that an ex vivo vascular niche would provide prohematopoietic signals to expand HSPCs while maintaining multipotency and self-renewal. To test this hypothesis, BM autologous CD34 + cells were expanded in endothelial cell (EC) coculture and transplanted in nonhuman primates. CD34 + C38 - HSPCs cocultured with ECs expanded up to 17-fold, with a significant increase in hematopoietic colony-forming activity compared with cells cultured with cytokines alone (colony-forming unit-granulocyte-erythroid-macrophage-monocyte; p < .005). BM CD34 + cells that were transduced with green fluorescent protein lentivirus vector and expanded on ECs engrafted long term with multilineage polyclonal reconstitution. Gene marking was observed in granulocytes, lymphocytes, platelets, and erythrocytes. Whole transcriptome analysis indicated that EC coculture altered the expression profile of 75 genes in the BM CD34 + cells without impeding the long-term engraftment potential. These findings show that an ex vivo vascular niche is an effective platform for expansion of adult BM HSPCs. Stem Cells Translational Medicine 2017;6:864-876. © 2016 The Authors Stem Cells Translational Medicine published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

PlGF repairs myocardial ischemia through mechanisms of angiogenesis, cardioprotection and recruitment of myo-angiogenic competent marrow progenitors.

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Hiroto Iwasaki

Full Text Available Despite preclinical success in regenerating and revascularizing the infarcted heart using angiogenic growth factors or bone marrow (BM cells, recent clinical trials have revealed less benefit from these therapies than expected.We explored the therapeutic potential of myocardial gene therapy of placental growth factor (PlGF, a VEGF-related angiogenic growth factor, with progenitor-mobilizing activity.Myocardial PlGF gene therapy improves cardiac performance after myocardial infarction, by inducing cardiac repair and reparative myoangiogenesis, via upregulation of paracrine anti-apoptotic and angiogenic factors. In addition, PlGF therapy stimulated Sca-1(+/Lin(- (SL BM progenitor proliferation, enhanced their mobilization into peripheral blood, and promoted their recruitment into the peri-infarct borders. Moreover, PlGF enhanced endothelial progenitor colony formation of BM-derived SL cells, and induced a phenotypic switch of BM-SL cells, recruited in the infarct, to the endothelial, smooth muscle and cardiomyocyte lineage.Such pleiotropic effects of PlGF on cardiac repair and regeneration offer novel opportunities in the treatment of ischemic heart disease.

Exercise increases the frequency of circulating hematopoietic progenitor cells, but reduces hematopoietic colony-forming capacity.

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Kroepfl, Julia Maria; Pekovits, Karin; Stelzer, Ingeborg; Fuchs, Robert; Zelzer, Sieglinde; Hofmann, Peter; Sedlmayr, Peter; Dohr, Gottfried; Wallner-Liebmann, Sandra; Domej, Wolfgang; Mueller, Wolfram

2012-11-01

Circulating hematopoietic progenitor cells (CPCs) may be triggered by physical exercise and/or normobaric hypoxia from the bone marrow. The aim of the study was to investigate the influence of physical exercise and normobaric hypoxia on CPC number and functionality in the peripheral blood as well as the involvement of oxidative stress parameters as possibly active agents. Ten healthy male subjects (25.3±4.4 years) underwent a standardized cycle incremental exercise test protocol (40 W+20 W/min) under either normoxic (FiO2 ∼0.21) or hypoxic conditions (FiO2exercise. The number of CPCs in the peripheral blood was analyzed by flow cytometry (CD34/CD45-positive cells). The functionality of cells present was addressed by secondary colony-forming unit-granulocyte macrophage (CFU-GM) assays. To determine a possible correlation between the mobilization of CPCs and reactive oxygen species, parameters for oxidative stress such as malondialdehyde (MDA) and myeloperoxidase (MPO) were obtained. Data showed a significant increase of CPC release under normoxic as well as hypoxic conditions after 10 min of recovery (Pexercise (Pexercise, possibly due to the influence of increased oxidative stress levels.

YKL-40-Induced Inhibition of miR-590-3p Promotes Interleukin-18 Expression and Angiogenesis of Endothelial Progenitor Cells

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Te-Mao Li

2017-04-01

Full Text Available YKL-40, also known as human cartilage glycoprotein-39 or chitinase-3-like-1, is a pro-inflammatory protein that is highly expressed in rheumatoid arthritis (RA patients. Angiogenesis is a critical step in the pathogenesis of RA, promoting the infiltration of inflammatory cells into joints and providing oxygen and nutrients to RA pannus. In this study, we examined the effects of YKL-40 in the production of the pro-inflammatory cytokine interleukin-18 (IL-18, and the stimulation of angiogenesis and accumulation of osteoblasts. We observed that YKL-40 induces IL-18 production in osteoblasts and thereby stimulates angiogenesis of endothelial progenitor cells (EPCs. We found that this process occurs through the suppression of miR-590-3p via the focal adhesion kinase (FAK/PI3K/Akt signaling pathway. YKL-40 inhibition reduced angiogenesis in in vivo models of angiogenesis: the chick embryo chorioallantoic membrane (CAM and Matrigel plug models. We report that YKL-40 stimulates IL-18 expression in osteoblasts and facilitates EPC angiogenesis.

Endothelial microparticles: Pathogenic or passive players in endothelial dysfunction in autoimmune rheumatic diseases?

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McCarthy, E M; Wilkinson, F L; Parker, B; Alexander, M Y

2016-11-01

Autoimmune rheumatic diseases are characterised by systemic inflammation and complex immunopathology, with an increased risk of cardiovascular disease, initiated by endothelial dysfunction in a chronic inflammatory environment. Endothelial microparticles (EMPs) are released into the circulation from activated endothelial cells and may therefore, reflect disease severity, vascular and endothelial dysfunction, that could influence disease pathogenesis via autocrine/paracrine signalling. The exact function of EMPs in rheumatic disease remains unknown, and this has initiated research to elucidate EMP composition and function, which may be determined by the mode of endothelial activation and the micro environment. To date, EMPs are thought to play a role in angiogenesis, thrombosis and inflammation by transferring specific proteins and microRNAs (miRs) to target cells. Here, we review the mechanisms underlying the generation and composition of EMPs and the clinical and experimental studies describing the involvement of EMPs in rheumatic diseases, since we have previously shown endothelial dysfunction and an elevated risk of cardiovascular disease are characteristics in systemic lupus erythematosus. We will also discuss the potential of EMPs as future biomarkers of cardiovascular risk in these diseases. Copyright © 2016 Elsevier Inc. All rights reserved.

CD133 antibody conjugation to decellularized human heart valves intended for circulating cell capture.

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Vossler, John D; Min Ju, Young; Williams, J Koudy; Goldstein, Steven; Hamlin, James; Lee, Sang Jin; Yoo, James J; Atala, Anthony

2015-09-03

The long term efficacy of tissue based heart valve grafts may be limited by progressive degeneration characterized by immune mediated inflammation and calcification. To avoid this degeneration, decellularized heart valves with functionalized surfaces capable of rapid in vivo endothelialization have been developed. The aim of this study is to examine the capacity of CD133 antibody-conjugated valve tissue to capture circulating endothelial progenitor cells (EPCs). Decellularized human pulmonary valve tissue was conjugated with CD133 antibody at varying concentrations and exposed to CD133 expressing NTERA-2 cl.D1 (NT2) cells in a microflow chamber. The amount of CD133 antibody conjugated on the valve tissue surface and the number of NT2 cells captured in the presence of shear stress was measured. Both the amount of CD133 antibody conjugated to the valve leaflet surface and the number of adherent NT2 cells increased as the concentration of CD133 antibody present in the surface immobilization procedure increased. The data presented in this study support the hypothesis that the rate of CD133(+) cell adhesion in the presence of shear stress to decellularized heart valve tissue functionalized by CD133 antibody conjugation increases as the quantity of CD133 antibody conjugated to the tissue surface increases.

Role of endothelial progenitor cells and inflammatory cytokines in healing of diabetic foot ulcers.

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Francesco Tecilazich

Full Text Available To evaluate changes in endothelial progenitor cells (EPCs and cytokines in patients with diabetic foot ulceration (DFU in association with wound healing.We studied healthy subjects, diabetic patients not at risk of DFU, at risk of DFU and with active DFU. We prospectively followed the DFU patients over a 12-week period. We also investigated similar changes in diabetic rabbit and mouse models of wound healing.All EPC phenotypes except the kinase insert domain receptor (KDR(+CD133(+ were reduced in the at risk and the DFU groups compared to the controls. There were no major EPC differences between the control and not at risk group, and between the at risk and DFU groups. Serum stromal-cell derived factor-1 (SDF-1 and stem cell factor (SCF were increased in DFU patients. DFU patients who healed their ulcers had lower CD34(+KDR(+ count at visits 3 and 4, serum c-reactive protein (CRP and granulocyte-macrophage colony-stimulating factor (GM-CSF at visit 1, interleukin-1 (IL-1 at visits 1 and 4. EPCs tended to be higher in both diabetic animal models when compared to their non-diabetic counterparts both before and ten days after wounding.Uncomplicated diabetes does not affect EPCs. EPCs are reduced in patients at risk or with DFU while complete wound healing is associated with CD34(+KDR(+ reduction, suggesting possible increased homing. Low baseline CRP, IL-1α and GM-CSF serum levels were associated with complete wound healing and may potentially serve as prognostic markers of DFU healing. No animal model alone is representative of the human condition, indicating the need for multiple experimental models.

Oral Mucosa Harbors a High Frequency of Endothelial Cells: A Novel Postnatal Cell Source for Angiogenic Regeneration.

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Zhou, Jian; Rogers, Jason H; Lee, Scott H; Sun, DongMing; Yao, Hai; Mao, Jeremy J; Kong, Kimi Y

2017-01-15

Endothelial progenitor cells/endothelial cells (EPCs/ECs) have great potential to treat pathological conditions such as cardiac infarction, muscle ischemia, and bone fractures, but isolation of EPC/ECs from existing cell sources is challenging due to their low EC frequency. We have isolated endothelial progenitor (EP)-like cells from rat oral mucosa and characterized their yield, immunophenotype, growth, and in vivo angiogenic potential. The frequency of EP-like cells derived from oral mucosa is thousands of folds higher than EPCs derived from donor-match bone marrow samples. EP-like cells from oral mucosa were positive for EC markers CD31, VE-Cadherin, and VEGFR2. Oral mucosa-derived EP-like cells displayed robust uptake of acetylated low-density lipoprotein and formed stable capillary networks in Matrigel. Subcutaneously implanted oral mucosa-derived EP-like cells anastomosed with host blood vessels, implicating their ability to elicit angiogenesis. Similar to endothelial colony-forming cells, EP-like cells from oral mucosa have a significantly higher proliferative rate than human umbilical vein endothelial cells. These findings identify a putative EPC source that is easily accessible in the oral cavity, potentially from discarded tissue specimens, and yet with robust yield and potency for angiogenesis in tissue and organ regeneration.

Endothelial dysfunction in the regulation of portal hypertension

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Iwakiri, Yasuko

2013-01-01

Portal hypertension is caused by an increased intrahepatic resistance, a major consequence of cirrhosis. Endothelial dysfunction in liver sinusoidal endothelial cells (LSECs) decreases the production of vasodilators, such as nitric oxide (NO) and favors vasoconstriction. This contributes to an increased vascular resistance in the intrahepatic/sinusoidal microcirculation. Portal hypertension, once developed, causes endothelial cell (EC) dysfunction in the extrahepatic, i.e. splanchnic and systemic, circulation. Unlike LSEC dysfunction, EC dysfunction in the splanchnic and systemic circulation overproduces vasodilator molecules, leading to arterial vasodilatation. In addition, portal hypertension leads to the formation of portosystemic collateral vessels. Both arterial vasodilatation and portosystemic collateral vessel formation exacerbate portal hypertension by increasing the blood flow through the portal vein. Pathologic consequences, such as esophageal varices and ascites, result. While the sequence of pathological vascular events in cirrhosis and portal hypertension have been elucidated, the underlying cellular and molecular mechanisms causing EC dysfunctions are not yet fully understood. This review article summarizes the current cellular and molecular studies on EC dysfunctions found during the development of cirrhosis and portal hypertension with a focus on intra- and extrahepatic circulation. The article ends by discussing future directions of study for EC dysfunctions. PMID:21745318

Taurine and magnesium supplementation enhances the function of endothelial progenitor cells through antioxidation in healthy men and spontaneously hypertensive rats.

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Katakawa, Mayumi; Fukuda, Noboru; Tsunemi, Akiko; Mori, Mari; Maruyama, Takashi; Matsumoto, Taro; Abe, Masanori; Yamori, Yukio

2016-12-01

Endothelial damage is repaired by endothelial progenitor cells (EPCs), which are pivotal in preventing cardiovascular diseases and prolonging lifespan. The WHO Cardiovascular Diseases and Alimentary Comparison Study demonstrated that dietary taurine and magnesium (Mg) intake suppresses cardiovascular diseases. We herein evaluate the effects of taurine and Mg supplementation on EPC function and oxidative stress in healthy men and spontaneously hypertensive rats (SHRs). Healthy men received taurine (3 g per day) or Mg (340 mg per day) for 2 weeks. SHRs and Wistar-Kyoto (WKY) rats were housed with high-salt drinking water (1% NaCl). The SHRs received 3% taurine solution and/or a high-Mg (600 mg per 100 g) diet for 4 weeks. Their peripheral blood mononuclear cells were separated to quantify EPC colony formation. Oxidative stress markers in their peripheral blood were evaluated using a free radical analytical system and a thiobarbituric acid reactive substance (TBARS) assay. Taurine and Mg supplementation significantly increased EPC colony numbers and significantly decreased free radical levels and TBARS scores in healthy men. Taurine and Mg supplementation significantly increased EPC colony numbers and significantly decreased TBARS scores and free radical levels in SHRs. Nicotinamide adenine dinucleotide phosphate oxidase component mRNA expression was significantly higher in the renal cortex of salt-loaded SHRs than in WKY rats, in which it was suppressed by taurine and Mg supplementation. Taurine and Mg supplementation increased EPC colony formation in healthy men and improved impaired EPC function in SHRs through antioxidation, indicating that the dietary intake of taurine and Mg may prolong lifespan by preventing the progression of cardiovascular diseases.

Correlation of circulating CD133+ progenitor subclasses with a mild phenotype in Duchenne muscular dystrophy patients.

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Chiara Marchesi

2008-05-01

Full Text Available Various prognostic serum and cellular markers have been identified for many diseases, such as cardiovascular diseases and tumor pathologies. Here we assessed whether the levels of certain stem cells may predict the progression of Duchenne muscular dystrophy (DMD.The levels of several subpopulations of circulating stem cells expressing the CD133 antigen were determined by flow cytometry in 70 DMD patients. The correlation between the levels and clinical status was assessed by statistical analysis. The median (+/-SD age of the population was 10.66+/-3.81 (range 3 to 20 years. The levels of CD133+CXCR4+CD34- stem cells were significantly higher in DMD patients compared to healthy controls (mean+/-standard deviation: 17.38+/-1.38 vs. 11.0+/-1.70; P = 0.03 with a tendency towards decreased levels in older patients. Moreover, the levels of this subpopulation of cells correlated with the clinical condition. In a subgroup of 19 DMD patients after 24 months of follow-up, increased levels of CD133+CXCR4+CD34- cells was shown to be associated with a phenotype characterised by slower disease progression. The circulating CD133+CXCR4+CD34- cells in patients from different ages did not exhibit significant differences in their myogenic and endothelial in vitro differentiation capacity.Our results suggest that levels of CD133+CXCR4+CD34- could function as a new prognostic clinical marker for the progression of DMD.

Endothelial marker-expressing stromal cells are critical for kidney formation.

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Mukherjee, Elina; Maringer, Katherine; Papke, Emily; Bushnell, Daniel; Schaefer, Caitlin; Kramann, Rafael; Ho, Jacqueline; Humphreys, Benjamin D; Bates, Carlton; Sims-Lucas, Sunder

2017-09-01

Kidneys are highly vascularized and contain many distinct vascular beds. However, the origins of renal endothelial cells and roles of the developing endothelia in the formation of the kidney are unclear. We have shown that the Foxd1-positive renal stroma gives rise to endothelial marker-expressing progenitors that are incorporated within a subset of peritubular capillaries; however, the significance of these cells is unclear. The purpose of this study was to determine whether deletion of Flk1 in the Foxd1 stroma was important for renal development. To that end, we conditionally deleted Flk1 (critical for endothelial cell development) in the renal stroma by breeding-floxed Flk1 mice ( Flk1 fl/fl ) with Foxd1cre mice to generate Foxd1cre; Flk1 fl/fl ( Flk1 ST-/- ) mice. We then performed FACsorting, histological, morphometric, and metabolic analyses of Flk1 ST-/- vs. control mice. We confirmed decreased expression of endothelial markers in the renal stroma of Flk1 ST-/- kidneys via flow sorting and immunostaining, and upon interrogation of embryonic and postnatal Flk1 ST-/- mice, we found they had dilated peritubular capillaries. Three-dimensional reconstructions showed reduced ureteric branching and fewer nephrons in developing Flk1 ST-/- kidneys vs. Juvenile Flk1 ST-/- kidneys displayed renal papillary hypoplasia and a paucity of collecting ducts. Twenty-four-hour urine collections revealed that postnatal Flk1 ST-/- mice had urinary-concentrating defects. Thus, while lineage-tracing revealed that the renal cortical stroma gave rise to a small subset of endothelial progenitors, these Flk1-expressing stromal cells are critical for patterning the peritubular capillaries. Also, loss of Flk1 in the renal stroma leads to nonautonomous-patterning defects in ureteric lineages. Copyright © 2017 the American Physiological Society.

Multilayer Membranes of Glycosaminoglycans and Collagen I Biomaterials Modulate the Function and Microvesicle Release of Endothelial Progenitor Cells.

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Dai, Bingyan; Pan, Qunwen; Li, Zhanghua; Zhao, Mingyan; Liao, Xiaorong; Wu, Keng; Ma, Xiaotang

2016-01-01

Multilayer composite membrane of biomaterials can increase the function of adipose stem cells or osteoprogenitor cells. Recent evidence indicates endothelial progenitor cells (EPCs) and EPCs released microvesicles (MVs) play important roles in angiogenesis and vascular repair. Here, we investigated the effects of biomaterial multilayer membranes of hyaluronic acid (HA) or chondroitin sulfate (CS) and Collagen I (Col I) on the functions and MVs release of EPCs. Layer-by-layer (LBL) technology was applied to construct the multilayer composite membranes. Four types of the membranes constructed by adsorbing either HA or CS and Col I alternatively with different top layers were studied. The results showed that all four types of multilayer composite membranes could promote EPCs proliferation and migration and inhibit cell senility, apoptosis, and the expression of activated caspase-3. Interestingly, these biomaterials increased the release and the miR-126 level of EPCs-MVs. Moreover, the CS-Col I membrane with CS on the top layer showed the most effects on promoting EPCs proliferation, EPCs-MV release, and miR-126 level in EPCs-MVs. In conclusion, HA/CS and Collagen I composed multilayer composite membranes can promote EPCs functions and release of miR-126 riched EPCs-MVs, which provides a novel strategy for tissue repair treatment.

Impact of a cardiac rehabilitation program and inflammatory state on endothelial progenitor cells in acute coronary syndrome patients.

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Cesari, Francesca; Marcucci, Rossella; Gori, Anna Maria; Burgisser, Costanza; Francini, Sara; Sofi, Francesco; Gensini, Gian Franco; Abbate, Rosanna; Fattirolli, Francesco

2013-09-01

Among the benefits of a cardiac rehabilitation (CR) program for patients after an acute coronary syndrome (ACS) is the mobilization of endothelial progenitor cells (EPCs). However not all patients respond to CR with an increase of EPC. We performed this study to identify the characteristics of patients who will not benefit from an increase of EPCs at the end of a CR program. 112 ACS patients were admitted to a four-week CR program. EPCs, high sensitivity C-reactive protein (hsCRP) and NT-ProBNP levels were determined at the beginning (T1) and at the end (T2) of the CR program. All patients performed a cardiopulmonary exercise test at T1 and at T2. EPCs were defined as CD34+KDR+, CD133+KDR+ and CD34+CD133+KDR+. hsCRP and NT-ProBNP were measured by nephelometric and immunometric method, respectively. At T2, we observed a significant increase of EPCs (p=0.001), VO2 peak, Watt max HDL-cholesterol (pprogram. A CR program determines an increase of EPCs with a decrease of CRP and NT-ProBNP. A different trend for EPCs can be detected among patients correlated to CRP levels and exercise tolerance. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

From here to there, progenitor cells and stem cells are everywhere in lung vascular remodeling

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Rebecca L. Heise

2016-08-01

Full Text Available The field of stem cell biology, cell therapy and regenerative medicine has expanded almost exponentially in the last decade. Clinical trials are evaluating the potential therapeutic use of stem cells in many adult and pediatric lung diseases with vascular component, such as bronchopulmonary dysplasia (BPD, chronic obstructive pulmonary disease (COPD, idiopathic pulmonary fibrosis (IPF or pulmonary arterial hypertension (PAH. Extensive research activity is exploring lung resident and circulating progenitor cells and their contribution to vascular complications of chronic lung diseases, and researchers hope to use resident or circulating stem/progenitor cells to treat chronic lung diseases and their vascular complications. It is becoming more and more clear that progress in mechanobiology will help to understand the various influences of physical forces and extracellular matrix composition on the phenotype and features of the progenitor cells and stem cells. The current review provides an overview of current concepts in the field.

Quantification of circulating mature endothelial cells using a whole blood four-color flow cytometric assay.

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Jacques, Nathalie; Vimond, Nadege; Conforti, Rosa; Griscelli, Franck; Lecluse, Yann; Laplanche, Agnes; Malka, David; Vielh, Philippe; Farace, Françoise

2008-09-15

Circulating endothelial cells (CEC) are currently proposed as a potential biomarker for measuring the impact of anti-angiogenic treatments in cancer. However, the lack of consensus on the appropriate method of CEC measurement has led to conflicting data in cancer patients. A validated assay adapted for evaluating the clinical utility of CEC in large cohorts of patients undergoing anti-angiogenic treatments is needed. We developed a four-color flow cytometric assay to measure CEC as CD31(+), CD146(+), CD45(-), 7-amino-actinomycin-D (7AAD)(-) events in whole blood. The distinctive features of the assay are: (1) staining of 1 ml whole blood, (2) use of a whole blood IgPE control to measure accurately background noise, (3) accumulation of a large number of events (almost 5 10(6)) to ensure statistical analysis, and (4) use of 10 microm fluorescent microbeads to evaluate the event size. Assay reproducibility was determined in duplicate aliquots of samples drawn from 20 metastatic cancer patients. Assay linearity was tested by spiking whole blood with low numbers of HUVEC. Five-color flow cytometric experiments with CD144 were performed to confirm the endothelial origin of the cells. CEC were measured in 20 healthy individuals and 125 patients with metastatic cancer. Reproducibility was good between duplicate aliquots (r(2)=0.948, mean difference between duplicates of 0.86 CEC/ml). Detected HUVEC correlated with spiked HUVEC (r(2)=0.916, mean recovery of 100.3%). Co-staining of CD31, CD146 and CD144 confirmed the endothelial nature of cells identified as CEC. Median CEC levels were 6.5/ml (range, 0-15) in healthy individuals and 15.0/ml (range, 0-179) in patients with metastatic carcinoma (p<0.001). The assay proposed here allows reproducible and sensitive measurement of CEC by flow cytometry and could help evaluate CEC as biomarkers of anti-angiogenic therapies in large cohorts of patients.

An anti-CD34 antibody-functionalized clinical-grade POSS-PCU nanocomposite polymer for cardiovascular stent coating applications: a preliminary assessment of endothelial progenitor cell capture and hemocompatibility.

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Aaron Tan

Full Text Available In situ endothelialization of cardiovascular implants has emerged in recent years as an attractive means of targeting the persistent problems of thrombosis and intimal hyperplasia. This study aimed to investigate the efficacy of immobilizing anti-CD34 antibodies onto a POSS-PCU nanocomposite polymer surface to sequester endothelial progenitor cells (EPCs from human blood, and to characterize the surface properties and hemocompatibility of this surface. Amine-functionalized fumed silica was used to covalently conjugate anti-CD34 to the polymer surface. Water contact angle, fluorescence microscopy, and scanning electron microscopy were used for surface characterization. Peripheral blood mononuclear cells (PBMCs were seeded on modified and pristine POSS-PCU polymer films. After 7 days, adhered cells were immunostained for the expression of EPC and endothelial cell markers, and assessed for the formation of EPC colonies. Hemocompatibility was assessed by thromboelastography, and platelet activation and adhesion assays. The number of EPC colonies formed on anti-CD34-coated POSS-PCU surfaces was not significantly higher than that of POSS-PCU (5.0±1.0 vs. 1.7±0.6, p>0.05. However, antibody conjugation significantly improved hemocompatibility, as seen from the prolonged reaction and clotting times, decreased angle and maximum amplitude (p<0.05, as well as decreased platelet adhesion (76.8±7.8 vs. 8.4±0.7, p<0.05 and activation. Here, we demonstrate that POSS-PCU surface immobilized anti-CD34 antibodies selectively captured CD34+ cells from peripheral blood, although only a minority of these were EPCs. Nevertheless, antibody conjugation significantly improves the hemocompatibility of POSS-PCU, and should therefore continue to be explored in combination with other strategies to improve the specificity of EPC capture to promote in situ endothelialization.

Endothelial cell repopulation after stenting determines in-stent neointima formation: effects of bare-metal vs. drug-eluting stents and genetic endothelial cell modification.

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Douglas, Gillian; Van Kampen, Erik; Hale, Ashley B; McNeill, Eileen; Patel, Jyoti; Crabtree, Mark J; Ali, Ziad; Hoerr, Robert A; Alp, Nicholas J; Channon, Keith M

2013-11-01

Understanding endothelial cell repopulation post-stenting and how this modulates in-stent restenosis is critical to improving arterial healing post-stenting. We used a novel murine stent model to investigate endothelial cell repopulation post-stenting, comparing the response of drug-eluting stents with a primary genetic modification to improve endothelial cell function. Endothelial cell repopulation was assessed en face in stented arteries in ApoE(-/-) mice with endothelial-specific LacZ expression. Stent deployment resulted in near-complete denudation of endothelium, but was followed by endothelial cell repopulation, by cells originating from both bone marrow-derived endothelial progenitor cells and from the adjacent vasculature. Paclitaxel-eluting stents reduced neointima formation (0.423 ± 0.065 vs. 0.240 ± 0.040 mm(2), P = 0.038), but decreased endothelial cell repopulation (238 ± 17 vs. 154 ± 22 nuclei/mm(2), P = 0.018), despite complete strut coverage. To test the effects of selectively improving endothelial cell function, we used transgenic mice with endothelial-specific overexpression of GTP-cyclohydrolase 1 (GCH-Tg) as a model of enhanced endothelial cell function and increased NO production. GCH-Tg ApoE(-/-) mice had less neointima formation compared with ApoE(-/-) littermates (0.52 ± 0.08 vs. 0.26 ± 0.09 mm(2), P = 0.039). In contrast to paclitaxel-eluting stents, reduced neointima formation in GCH-Tg mice was accompanied by increased endothelial cell coverage (156 ± 17 vs. 209 ± 23 nuclei/mm(2), P = 0.043). Drug-eluting stents reduce not only neointima formation but also endothelial cell repopulation, independent of strut coverage. In contrast, selective targeting of endothelial cell function is sufficient to improve endothelial cell repopulation and reduce neointima formation. Targeting endothelial cell function is a rational therapeutic strategy to improve vascular healing and decrease neointima formation after stenting.

The isolation and in vitro expansion of hepatic Sca-1 progenitor cells

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Clayton, Elizabeth; Forbes, Stuart J.

2009-01-01

The intra-hepatic population of liver progenitor cells expands during liver injury when hepatocyte proliferation is inhibited. These cells can be purified by density gradient centrifugation and cultured. Separated by size only this population contains small cells of hematopoietic, epithelial and endothelial lineages and is thought to contain liver stem cells. The identity of liver stem cells remains unknown although there is some evidence that tissue Sca1 + CD45 - cells display progenitor cell characteristics. We identified both intra-hepatic and gall bladder Sca1 + cells following liver injury and expanded ex vivo Sca1 cells as part of heterogenous cell culture or as a purified population. We found significant difference between the proliferation of Sca-1 cells when plated on laminin or collagen I while proliferation of heterogenous population was not affected by the extracellular matrix indicating the necessity for culture of Sca1 + cells with laminin matrix or laminin producing cells in long term liver progenitor cell cultures.

Endurance Capacity Is Not Correlated with Endothelial Function in Male University Students

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Wu, Fang; Su, Chen; Fan, Zhen-guo; Zhu, Zhu; Tao, Jun; Huang, Yi-jun

2014-01-01

Background Endurance capacity, assessed by 1000-meter (1000 m) run of male university students, is an indicator of cardiovascular fitness in Chinese students physical fitness surveillance. Although cardiovascular fitness is related to endothelial function closely in patients with cardiovascular diseases, it remains unclear whether endurance capacity correlates with endothelial function, especially with circulating endothelial microparticles (EMPs), a new sensitive marker of endothelial dysfunction in young students. The present study aimed to investigate the relationship between endurance capacity and endothelial function in male university students. Methods Forty-seven healthy male university students (mean age, 20.1±0.6 years; mean height, 172.4±6.3 cm; and mean weight, 60.0±8.2 kg) were recruited in this study. The measurement procedure of 1000 m run time was followed to Chinese national students Constitutional Health Criterion. Endothelium function was assessed by flow-mediated vasodilation (FMD) in the brachial artery measured by ultrasonic imaging, and the level of circulating EMPs was measured by flow cytometry. Cardiovascular fitness indicator - maximal oxygen uptake (VO2 max) - was also measured on a cycle ergometer using a portable gas analyzer. Results 1000 m run time was correlated with VO2max (r = −0.399, p0.05). Conclusion The correlations between endurance capacity or cardiovascular fitness and endothelial function were not found in healthy Chinese male university students. These results suggest that endurance capacity may not reflect endothelial function in healthy young adults with well preserved FMD and low level of circulating CD31+/CD42-EMPs. PMID:25101975

Endothelial actions of atrial and B-type natriuretic peptides.

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Kuhn, Michaela

2012-05-01

The cardiac hormone atrial natriuretic peptide (ANP) is critically involved in the maintenance of arterial blood pressure and intravascular volume homeostasis. Its cGMP-producing GC-A receptor is densely expressed in the microvascular endothelium of the lung and systemic circulation, but the functional relevance is controversial. Some studies reported that ANP stimulates endothelial cell permeability, whereas others described that the peptide attenuates endothelial barrier dysfunction provoked by inflammatory agents such as thrombin or histamine. Many studies in vitro addressed the effects of ANP on endothelial proliferation and migration. Again, both pro- and anti-angiogenic properties were described. To unravel the role of the endothelial actions of ANP in vivo, we inactivated the murine GC-A gene selectively in endothelial cells by homologous loxP/Cre-mediated recombination. Our studies in these mice indicate that ANP, via endothelial GC-A, increases endothelial albumin permeability in the microcirculation of the skin and skeletal muscle. This effect is critically involved in the endocrine hypovolaemic, hypotensive actions of the cardiac hormone. On the other hand the homologous GC-A-activating B-type NP (BNP), which is produced by cardiac myocytes and many other cell types in response to stressors such as hypoxia, possibly exerts more paracrine than endocrine actions. For instance, within the ischaemic skeletal muscle BNP released from activated satellite cells can improve the regeneration of neighbouring endothelia. This review will focus on recent advancements in our understanding of endothelial NP/GC-A signalling in the pulmonary versus systemic circulation. It will discuss possible mechanisms accounting for the discrepant observations made for the endothelial actions of this hormone-receptor system and distinguish between (patho)physiological and pharmacological actions. Lastly it will emphasize the potential therapeutical implications derived from the

Long-term, regular remote ischemic preconditioning improves endothelial function in patients with coronary heart disease

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Liang, Y.; Li, Y.P.; He, F.; Liu, X.Q.; Zhang, J.Y. [Department of Cardiology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou (China)

2015-04-28

Remote ischemic preconditioning (RIPre) can prevent myocardial injury. The purpose of this study was to assess the beneficial effects of long-term regular RIPre on human arteries. Forty patients scheduled for coronary artery bypass graft (CABG) surgery were assigned randomly to a RIPre group (n=20) or coronary heart disease (CHD) group (n=20). Twenty patients scheduled for mastectomy were enrolled as a control group. RIPre was achieved by occluding arterial blood flow 5 min with a mercury sphygmomanometer followed by a 5-min reperfusion period, and this was repeated 4 times. The RIPre procedure was repeated 3 times a day for 20 days. In all patients, arterial fragments discarded during surgery were collected to evaluate endothelial function by flow-mediated dilation (FMD), CD34{sup +} monocyte count, and endothelial nitric oxide synthase (eNOS expression). Phosphorylation levels of STAT-3 and Akt were also assayed to explore the underlying mechanisms. Compared with the CHD group, long-term regular RIPre significantly improved FMD after 20 days (8.5±2.4 vs 4.9±4.2%, P<0.05) and significantly reduced troponin after CABG surgery (0.72±0.31 and 1.64±0.19, P<0.05). RIPre activated STAT-3 and increased CD34{sup +} endothelial progenitor cell counts found in arteries. Long-term, regular RIPre improved endothelial function in patients with CHD, possibly due to STAT-3 activation, and this may have led to an increase in endothelial progenitor cells.

Experimental study of an endothelial progenitor cell coated stent in transjugular intrahepatic portosystemic shunt

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Shi Hongjian; Teng Gaojun; Cao Aihong; Chen Jun; Deng Gang

2009-01-01

Objective: To evaluate the efficacy of a self-expandable metal stent coated with autologous endothelial progenitor cells (EPCs) for prevention of restenosis in transjugular intrahepatic portosystemic shunt (TIPS) in a swine model. Methods: EPCs were coated on the metal stents using fibrin gel before TIPS procedure. TIPS was performed in 15 young adult pigs, using an autologous EPC-seeded stent (treatment group, n=9) or a conventional bare metal stent (control group, n=6). All pigs were sacrificed at 2 weeks after TIPS procedure. Portography was performed immediately before the euthanasia. Gross and microscopic pathological exams and immunohistochemical exams of the TIPS track specimens were performed. Fisher test and t test were used to analyse the data. Results: TIPS was performed successfully in all the 15 swine. On day 14 of follow-up, direct portography and necropsy demonstrated that 5 shunts remained patent, 2 shunts stenosed, and the remaining 2 shunts occluded in the treatment group (n=9); while 5 shunts were occluded and one shunt was stenotic in the control group (n=6). The patency rate was 56% vs 0 (P=0.03) between the two groups. Histological analyses showed a greater pseudo-intimal hyperplasia in the TIPS track of the control group than that of the treatment group (pseudointimal thickness at hepatic vein, hepatic parenchyma and portal vein site was (1.2±0.4), (1.3±0.5), (1.5±0.4) mm vs (1.0±0.6), (0.9±0.5), (1.0±0.4) mm respectively (P<0.05). Conclusion: The EPC-coated metal stent is feasibly constructed in vitro and improves the patency in TIPS in a porcine model. (authors)

Influence on bionomics of endothelial progenitor cells labeling with magnetic nanoparticles

International Nuclear Information System (INIS)

Mai Xiaoli; Teng Gaojun; Ma Zhanlong; Sun Junhui; Zhang Yu; Gu Ning

2008-01-01

Objective: To explore the influence of home synthesize magnetic iron oxide (called Fe 2 O 3 -PLL) labeling on peripheral blood endothelial progenitor cells (EPCs) bionomics to provide experimental foundation for MR imaging ex and in vivo. Methods: Fe 2 O 3 was incubated with PLL for 2 hours to obtain a complex of Fe 2 O 3 -PLL. Rabbit peripheral blood mononuclear cells were isolated and EPCs were selected by adherence method. Fe 2 O 3 -PLL was used to label EPCs. Prussian blue stain and electron microscope was used for showing intracellular iron. MTF assay was assessed to evaluate the difference of growth curve between unlabeled and labeled with 25 mg/L Fe 2 O 3 -PLL. Flow cytometry was performed to analyze cell cycle, cell apoptosis and the expression of surface markers of labeled and unlabeled cells. Expressions of eNOS, KDR and vWF at mRNA levels among unlabeled and labeled EPCs were detected by real-time polymerase chain reaction. Calcium ion channel and membrane fluidity were observed and analyzed by laser confocal microscopy. Statistical analyses were used with ANOVA and t test. Results: Almost 100% cells were labeled by Fe 2 O 3 -PLL, iron-containing vesicles were intracytoplasma. There was no statistical difference in cells growth curve, cell life cycle [(93.74±3.52)%, (94.57±3.66)%] and cell apoptosis rate (12.89±1.81)%, (11.67±1.18)%) between labeling with Fe 2 O 3 -PLL at a concentration of 25 mg/L and unlabeled cells (t=0.283, P>0.05; t=0.977, P>0.05). There was also no statistical difference in relative amount of eNOS, KDR and vWF at mRNA levels and the expression of surface phenotypic markers (CD34, CD106, CD146 and KDR) between two groups (P>0.05). In addition, Labeling had little influence on calcium ion channel and didn't significantly alter cell membrane fluidity. Conclusions: The rabbit peripheral blood EPCs can be effective labeled with Fe 2 O 3 -PLL and without significant influence on cells bionomics at a low concentration of 25 mg

p38 MAPK and JNK antagonistically control senescence and cytoplasmic p16INK4A expression in doxorubicin-treated endothelial progenitor cells.

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Paolo Spallarossa

Full Text Available Patients treated with low-dose anthracyclines often show late onset cardiotoxicity. Recent studies suggest that this form of cardiotoxicity is the result of a progenitor cell disease. In this study we demonstrate that Cord Blood Endothelial Progenitor Cells (EPCs exposed to low, sub-apoptotic doses of doxorubicin show a senescence phenotype characterized by increased SA-b-gal activity, decreased TRF2 and chromosomal abnormalities, enlarged cell shape, and disarrangement of F-actin stress fibers accompanied by impaired migratory ability. P16( INK4A localizes in the cytoplasm of doxorubicin-induced senescent EPCs and not in the nucleus as is the case in EPCs rendered senescent by different stimuli. This localization together with the presence of an arrest in G2, and not at the G1 phase boundary, which is what usually occurs in response to the cell cycle regulatory activity of p16(INK4A, suggests that doxorubicin-induced p16( INK4A does not regulate the cell cycle, even though its increase is closely associated with senescence. The effects of doxorubicin are the result of the activation of MAPKs p38 and JNK which act antagonistically. JNK attenuates the senescence, p16( INK4A expression and cytoskeleton remodeling that are induced by activated p38. We also found that conditioned medium from doxorubicin-induced senescent cardiomyocytes does not attract untreated EPCs, unlike conditioned medium from apoptotic cardiomyocytes which has a strong chemoattractant capacity. In conclusion, this study provides a better understanding of the senescence of doxorubicin-treated EPCs, which may be helpful in preventing and treating late onset cardiotoxicity.

Assessing Clinical Outcomes in Colorectal Cancer with Assays for Invasive Circulating Tumor Cells.

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Zhang, Yue; Zarrabi, Kevin; Hou, Wei; Madajewicz, Stefan; Choi, Minsig; Zucker, Stanley; Chen, Wen-Tien

2018-06-06

Colorectal carcinoma (CRC) is the second leading cause of cancer-related mortality. The goals of this study are to evaluate the association between levels of invasive circulating tumor cells (iCTCs) with CRC outcomes and to explore the molecular characteristics of iCTCs. Peripheral blood from 93 patients with Stage I⁻IV CRC was obtained and assessed for the detection and characterization of iCTCs using a functional collagen-based adhesion matrix (CAM) invasion assay. Patients were followed and assessed for overall survival. Tumor cells isolated by CAM were characterized using cell culture and microarray analyses. Of 93 patients, 88 (95%) had detectable iCTCs, ranging over 0⁻470 iCTCs/mL. Patients with Stage I⁻IV disease exhibited median counts of 0.0 iCTCs/mL ( n = 6), 13.0 iCTCs/mL ( n = 12), 41.0 iCTCs/mL ( n = 12), and 133.0 iCTCs/mL ( n = 58), respectively ( p < 0.001). Kaplan⁻Meier curve analysis demonstrated a significant survival benefit in patients with low iCTC counts compared with in patients with high iCTC counts (log-rank p < 0.001). Multivariable Cox model analysis revealed that iCTC count was an independent prognostic factor of overall survival ( p = 0.009). Disease stage ( p = 0.01, hazard ratio 1.66; 95% confidence interval: 1.12⁻2.47) and surgical intervention ( p = 0.03, HR 0.37; 95% CI: 0.15⁻0.92) were also independent prognostic factors. Gene expression analysis demonstrated the expression of both endothelial and tumor progenitor cell biomarkers in iCTCs. CAM-based invasion assay shows a high detection sensitivity of iCTCs that inversely correlated with overall survival in CRC patients. Functional and gene expression analyses showed the phenotypic mosaics of iCTCs, mimicking the survival capability of circulating endothelial cells in the blood stream.

Human endothelial precursor cells express tumor endothelial marker 1/endosialin/CD248.

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Bagley, Rebecca G; Rouleau, Cecile; St Martin, Thia; Boutin, Paula; Weber, William; Ruzek, Melanie; Honma, Nakayuki; Nacht, Mariana; Shankara, Srinivas; Kataoka, Shiro; Ishida, Isao; Roberts, Bruce L; Teicher, Beverly A

2008-08-01

Angiogenesis occurs during normal physiologic processes as well as under pathologic conditions such as tumor growth. Serial analysis of gene expression profiling revealed genes [tumor endothelial markers (TEM)] that are overexpressed in tumor endothelial cells compared with normal adult endothelial cells. Because blood vessel development of malignant tumors under certain conditions may include endothelial precursor cells (EPC) recruited from bone marrow, we investigated TEM expression in EPC. The expression of TEM1 or endosialin (CD248) and other TEM has been discovered in a population of vascular endothelial growth factor receptor 2+/CD31+/CD45-/VE-cadherin+ EPC derived from human CD133+/CD34+ cells. EPC share some properties with fully differentiated endothelial cells from normal tissue, yet reverse transcription-PCR and flow cytometry reveal that EPC express higher levels of endosialin at the molecular and protein levels. The elevated expression of endosialin in EPC versus mature endothelial cells suggests that endosialin is involved in the earlier stages of tumor angiogenesis. Anti-endosialin antibodies inhibited EPC migration and tube formation in vitro. In vivo, immunohistochemistry indicated that human EPC continued to express endosialin protein in a Matrigel plug angiogenesis assay established in nude mice. Anti-endosialin antibodies delivered systemically at 25 mg/kg were also able to inhibit circulating murine EPC in nude mice bearing s.c. SKNAS tumors. EPC and bone marrow-derived cells have been shown previously to incorporate into malignant blood vessels in some instances, yet they remain controversial in the field. The data presented here on endothelial genes that are up-regulated in tumor vasculature and in EPC support the hypothesis that the angiogenesis process in cancer can involve EPC.

Aromatic Hydrocarbon Receptor Suppresses Prostate Cancer Bone Metastasis Cells-Induced Vasculogenesis of Endothelial Progenitor Cells under Hypoxia

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Shuai Huang

2016-07-01

Full Text Available Background/Aims: Hypoxia leads to the development of neovascularization in solid tumor by regulating VEGF expression. Aromatic hydrocarbon receptor (AHR, a receptor for dioxin-like compounds, functions as a transcription factor through dimerization with hypoxia-inducible factors 1β (HIF-1β and inhibits the secretion of vascular endothelial growth factor (VEGF. The purpose of this study was to explore whether AHR can suppress hypoxia-induced VEGF production in prostate bone metastasis cells and repress neovascularization in endothelial progenitor cells (EPCs, and, if so, through what mechanisms. Methods: PC-3 or LNCaP cells induced angiogenesis was detected by Matrigel-based tube formation assay, mRNA expression levels was measured by qRT-PCR, VEGF secretion level was determined by ELISA assay, respectively. Results: AHR activation inhibits hypoxia-induced adhesiveness and vasculogenesis of EPCs induced by PC-3 or LNCaP cells under hypoxia. Moreover, AHR activation suppressed hypoxia-induced VEGF production in PC-3 and LNCaP cells (48 ± 14% in PC-3, p = 0.000; 41 ± 14% in LNCaP, p = 0.000 by attenuating HIF-1α and HIF-1β level that in turn diminished the angiogenic ability of EPCs in vitro. Furthermore, we found the mRNA level of hypoxia-inducible factors 1α (HIF-1α (1.54 ± 0.13 fold in PC-3, p = 0.002, 1.62 ± 0.12 fold in LNCaP, p = 0.001 and HIF-1β (1.67 ± 0.23 fold in PC-3, p = 0.007; 1.75 ± 0.26 fold in LNCaP, p=0.008 were upregulated in prostate cancer bone metastasis PC-3 and LNCaP cell lines in response to hypoxia, and revealed that the regulation of VEGF by HIF-1α and HIF-1β was possibly mediated by the activation of phosphatidylinositol 3-kinase pathway. Conclusion: By providing a mechanistic insight into the modulation of neovascularization by AHR ligand, we suggest that AHR ligand has a strong potential of being a new therapeutic agent with applications in the field of bone metastatic prostate cancer.

Increased Circulating Endothelial Microparticles Associated with PAK4 Play a Key Role in Ventilation-Induced Lung Injury Process

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Shuming Pan

2017-01-01

Full Text Available Inappropriate mechanical ventilation (MV can result in ventilator-induced lung injury (VILI. Probing mechanisms of VILI and searching for effective methods are current areas of research focus on VILI. The present study aimed to probe into mechanisms of endothelial microparticles (EMPs in VILI and the protective effects of Tetramethylpyrazine (TMP against VILI. In this study, C57BL/6 and TLR4KO mouse MV models were used to explore the function of EMPs associated with p21 activated kinases-4 (PAK-4 in VILI. Both the C57BL/6 and TLR4 KO groups were subdivided into a mechanical ventilation (MV group, a TMP + MV group, and a control group. After four hours of high tidal volume (20 ml/kg MV, the degree of lung injury and the protective effects of TMP were assessed. VILI inhibited the cytoskeleton-regulating protein of PAK4 and was accompanied by an increased circulating EMP level. The intercellular junction protein of β-catenin was also decreased accompanied by a thickening alveolar wall, increased lung W/D values, and neutrophil infiltration. TMP alleviated VILI via decreasing circulating EMPs, stabilizing intercellular junctions, and alleviating neutrophil infiltration.

High frequency of endothelial colony forming cells marks a non-active myeloproliferative neoplasm with high risk of splanchnic vein thrombosis.

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Vittorio Rosti

Full Text Available Increased mobilization of circulating endothelial progenitor cells may represent a new biological hallmark of myeloproliferative neoplasms. We measured circulating endothelial colony forming cells (ECFCs in 106 patients with primary myelofibrosis, fibrotic stage, 49 with prefibrotic myelofibrosis, 59 with essential thrombocythemia or polycythemia vera, and 43 normal controls. Levels of ECFC frequency for patient's characteristics were estimated by using logistic regression in univariate and multivariate setting. The sensitivity, specificity, likelihood ratios, and positive predictive value of increased ECFC frequency were calculated for the significantly associated characteristics. Increased frequency of ECFCs resulted independently associated with history of splanchnic vein thrombosis (adjusted odds ratio = 6.61, 95% CI = 2.54-17.16, and a summary measure of non-active disease, i.e. hemoglobin of 13.8 g/dL or lower, white blood cells count of 7.8×10(9/L or lower, and platelet count of 400×10(9/L or lower (adjusted odds ratio = 4.43, 95% CI = 1.45-13.49 Thirteen patients with splanchnic vein thrombosis non associated with myeloproliferative neoplasms were recruited as controls. We excluded a causal role of splanchnic vein thrombosis in ECFCs increase, since no control had elevated ECFCs. We concluded that increased frequency of ECFCs represents the biological hallmark of a non-active myeloproliferative neoplasm with high risk of splanchnic vein thrombosis. The recognition of this disease category copes with the phenotypic mimicry of myeloproliferative neoplasms. Due to inherent performance limitations of ECFCs assay, there is an urgent need to arrive to an acceptable standardization of ECFC assessment.

Diabetes-Induced Oxidative Stress in Endothelial Progenitor Cells May Be Sustained by a Positive Feedback Loop Involving High Mobility Group Box-1

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Han Wu

2016-01-01

Full Text Available Oxidative stress is considered to be a critical factor in diabetes-induced endothelial progenitor cell (EPC dysfunction, although the underlying mechanisms are not fully understood. In this study, we investigated the role of high mobility group box-1 (HMGB-1 in diabetes-induced oxidative stress. HMGB-1 was upregulated in both serum and bone marrow-derived monocytes from diabetic mice compared with control mice. In vitro, advanced glycation end productions (AGEs induced, expression of HMGB-1 in EPCs and in cell culture supernatants in a dose-dependent manner. However, inhibition of oxidative stress with N-acetylcysteine (NAC partially inhibited the induction of HMGB-1 induced by AGEs. Furthermore, p66shc expression in EPCs induced by AGEs was abrogated by incubation with glycyrrhizin (Gly, while increased superoxide dismutase (SOD activity in cell culture supernatants was observed in the Gly treated group. Thus, HMGB-1 may play an important role in diabetes-induced oxidative stress in EPCs via a positive feedback loop involving the AGE/reactive oxygen species/HMGB-1 pathway.

PSGL-1–mediated activation of EphB4 increases the proangiogenic potential of endothelial progenitor cells

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Foubert, Philippe; Silvestre, Jean-Sébastien; Souttou, Boussad; Barateau, Véronique; Martin, Coralie; Ebrahimian, Téni G.; Leré-Déan, Carole; Contreres, Jean Olivier; Sulpice, Eric; Levy, Bernard I.; Plouët, Jean; Tobelem, Gérard; Le Ricousse-Roussanne, Sophie

2007-01-01

Endothelial progenitor cell (EPC) transplantation has beneficial effects for therapeutic neovascularization; however, only a small proportion of injected cells home to the lesion and incorporate into the neocapillaries. Consequently, this type of cell therapy requires substantial improvement to be of clinical value. Erythropoietin-producing human hepatocellular carcinoma (Eph) receptors and their ephrin ligands are key regulators of vascular development. We postulated that activation of the EphB4/ephrin-B2 system may enhance EPC proangiogenic potential. In this report, we demonstrate in a nude mouse model of hind limb ischemia that EphB4 activation with an ephrin-B2–Fc chimeric protein increases the angiogenic potential of human EPCs. This effect was abolished by EphB4 siRNA, confirming that it is mediated by EphB4. EphB4 activation enhanced P selectin glycoprotein ligand-1 (PSGL-1) expression and EPC adhesion. Inhibition of PSGL-1 by siRNA reversed the proangiogenic and adhesive effects of EphB4 activation. Moreover, neutralizing antibodies to E selectin and P selectin blocked ephrin-B2–Fc–stimulated EPC adhesion properties. Thus, activation of EphB4 enhances EPC proangiogenic capacity through induction of PSGL-1 expression and adhesion to E selectin and P selectin. Therefore, activation of EphB4 is an innovative and potentially valuable therapeutic strategy for improving the recruitment of EPCs to sites of neovascularization and thereby the efficiency of cell-based proangiogenic therapy. PMID:17510705

Coenzyme Q10 Attenuates High Glucose-Induced Endothelial Progenitor Cell Dysfunction through AMP-Activated Protein Kinase Pathways

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Hsiao-Ya Tsai

2016-01-01

Full Text Available Coenzyme Q10 (CoQ10, an antiapoptosis enzyme, is stored in the mitochondria of cells. We investigated whether CoQ10 can attenuate high glucose-induced endothelial progenitor cell (EPC apoptosis and clarified its mechanism. EPCs were incubated with normal glucose (5 mM or high glucose (25 mM enviroment for 3 days, followed by treatment with CoQ10 (10 μM for 24 hr. Cell proliferation, nitric oxide (NO production, and JC-1 assay were examined. The specific signal pathways of AMP-activated protein kinase (AMPK, eNOS/Akt, and heme oxygenase-1 (HO-1 were also assessed. High glucose reduced EPC functional activities, including proliferation and migration. Additionally, Akt/eNOS activity and NO production were downregulated in high glucose-stimulated EPCs. Administration of CoQ10 ameliorated high glucose-induced EPC apoptosis, including downregulation of caspase 3, upregulation of Bcl-2, and increase in mitochondrial membrane potential. Furthermore, treatment with CoQ10 reduced reactive oxygen species, enhanced eNOS/Akt activity, and increased HO-1 expression in high glucose-treated EPCs. These effects were negated by administration of AMPK inhibitor. Transplantation of CoQ10-treated EPCs under high glucose conditions into ischemic hindlimbs improved blood flow recovery. CoQ10 reduced high glucose-induced EPC apoptosis and dysfunction through upregulation of eNOS, HO-1 through the AMPK pathway. Our findings provide a potential treatment strategy targeting dysfunctional EPC in diabetic patients.

Coenzyme Q10 Attenuates High Glucose-Induced Endothelial Progenitor Cell Dysfunction through AMP-Activated Protein Kinase Pathways

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Tsai, Hsiao-Ya; Lin, Chih-Pei; Huang, Po-Hsun; Li, Szu-Yuan; Chen, Jia-Shiong; Lin, Feng-Yen; Chen, Jaw-Wen; Lin, Shing-Jong

2016-01-01

Coenzyme Q10 (CoQ10), an antiapoptosis enzyme, is stored in the mitochondria of cells. We investigated whether CoQ10 can attenuate high glucose-induced endothelial progenitor cell (EPC) apoptosis and clarified its mechanism. EPCs were incubated with normal glucose (5 mM) or high glucose (25 mM) enviroment for 3 days, followed by treatment with CoQ10 (10 μM) for 24 hr. Cell proliferation, nitric oxide (NO) production, and JC-1 assay were examined. The specific signal pathways of AMP-activated protein kinase (AMPK), eNOS/Akt, and heme oxygenase-1 (HO-1) were also assessed. High glucose reduced EPC functional activities, including proliferation and migration. Additionally, Akt/eNOS activity and NO production were downregulated in high glucose-stimulated EPCs. Administration of CoQ10 ameliorated high glucose-induced EPC apoptosis, including downregulation of caspase 3, upregulation of Bcl-2, and increase in mitochondrial membrane potential. Furthermore, treatment with CoQ10 reduced reactive oxygen species, enhanced eNOS/Akt activity, and increased HO-1 expression in high glucose-treated EPCs. These effects were negated by administration of AMPK inhibitor. Transplantation of CoQ10-treated EPCs under high glucose conditions into ischemic hindlimbs improved blood flow recovery. CoQ10 reduced high glucose-induced EPC apoptosis and dysfunction through upregulation of eNOS, HO-1 through the AMPK pathway. Our findings provide a potential treatment strategy targeting dysfunctional EPC in diabetic patients. PMID:26682233

Secondhand smoke exposure and endothelial stress in children and adolescents.

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Groner, Judith A; Huang, Hong; Nagaraja, Haikady; Kuck, Jennifer; Bauer, John Anthony

2015-01-01

Links between secondhand smoke exposure and cardiovascular disease in adults are well established. Little is known about the impact of this exposure on cardiovascular status during childhood. The purpose of this study was to investigate relationships between secondhand smoke exposure in children and adolescents and cardiovascular disease risk--systemic inflammation, endothelial stress, and endothelial repair. A total of 145 subjects, aged 9 to 18 years, were studied. Tobacco smoke exposure was determined by hair nicotine level. Cardiovascular risk was assessed by markers of systemic inflammation (C-reactive protein [CRP] and adiponectin); by soluble intercellular adhesion molecule 1 (s-ICAM1), which measures endothelial activation after surface vascular injury; and by endothelial repair. This was measured by prevalence of endothelial progenitor cells (EPCs), which are bone marrow-derived cells that home preferentially to sites of vascular damage. Hair nicotine was directly correlated with s-ICAM1 (r = 0.4090, P Secondhand smoke exposure during childhood and adolescence is detrimental to vascular health because s-ICAM1 is a marker for endothelial activation and stress after vascular surface injury, and EPCs contribute to vascular repair. The fact that body mass index is also a factor in the model predicting s-ICAM1 is concerning, in that 2 risk factors may both contribute to endothelial stress. Copyright © 2015 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.

Circulating histones are mediators of trauma-associated lung injury.

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Abrams, Simon T; Zhang, Nan; Manson, Joanna; Liu, Tingting; Dart, Caroline; Baluwa, Florence; Wang, Susan Siyu; Brohi, Karim; Kipar, Anja; Yu, Weiping; Wang, Guozheng; Toh, Cheng-Hock

2013-01-15

Acute lung injury is a common complication after severe trauma, which predisposes patients to multiple organ failure. This syndrome largely accounts for the late mortality that arises and despite many theories, the pathological mechanism is not fully understood. Discovery of histone-induced toxicity in mice presents a new dimension for elucidating the underlying pathophysiology. To investigate the pathological roles of circulating histones in trauma-induced lung injury. Circulating histone levels in patients with severe trauma were determined and correlated with respiratory failure and Sequential Organ Failure Assessment (SOFA) scores. Their cause-effect relationship was studied using cells and mouse models. In a cohort of 52 patients with severe nonthoracic blunt trauma, circulating histones surged immediately after trauma to levels that were toxic to cultured endothelial cells. The high levels were significantly associated with the incidence of acute lung injury and SOFA scores, as well as markers of endothelial damage and coagulation activation. In in vitro systems, histones damaged endothelial cells, stimulated cytokine release, and induced neutrophil extracellular trap formation and myeloperoxidase release. Cellular toxicity resulted from their direct membrane interaction and resultant calcium influx. In mouse models, cytokines and markers for endothelial damage and coagulation activation significantly increased immediately after trauma or histone infusion. Pathological examinations showed that lungs were the predominantly affected organ with edema, hemorrhage, microvascular thrombosis, and neutrophil congestion. An anti-histone antibody could reduce these changes and protect mice from histone-induced lethality. This study elucidates a new mechanism for acute lung injury after severe trauma and proposes that circulating histones are viable therapeutic targets for improving survival outcomes in patients.

Circulating Histones Are Mediators of Trauma-associated Lung Injury

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Abrams, Simon T.; Zhang, Nan; Manson, Joanna; Liu, Tingting; Dart, Caroline; Baluwa, Florence; Wang, Susan Siyu; Brohi, Karim; Kipar, Anja; Yu, Weiping

2013-01-01

Rationale: Acute lung injury is a common complication after severe trauma, which predisposes patients to multiple organ failure. This syndrome largely accounts for the late mortality that arises and despite many theories, the pathological mechanism is not fully understood. Discovery of histone-induced toxicity in mice presents a new dimension for elucidating the underlying pathophysiology. Objectives: To investigate the pathological roles of circulating histones in trauma-induced lung injury. Methods: Circulating histone levels in patients with severe trauma were determined and correlated with respiratory failure and Sequential Organ Failure Assessment (SOFA) scores. Their cause–effect relationship was studied using cells and mouse models. Measurements and Main Results: In a cohort of 52 patients with severe nonthoracic blunt trauma, circulating histones surged immediately after trauma to levels that were toxic to cultured endothelial cells. The high levels were significantly associated with the incidence of acute lung injury and SOFA scores, as well as markers of endothelial damage and coagulation activation. In in vitro systems, histones damaged endothelial cells, stimulated cytokine release, and induced neutrophil extracellular trap formation and myeloperoxidase release. Cellular toxicity resulted from their direct membrane interaction and resultant calcium influx. In mouse models, cytokines and markers for endothelial damage and coagulation activation significantly increased immediately after trauma or histone infusion. Pathological examinations showed that lungs were the predominantly affected organ with edema, hemorrhage, microvascular thrombosis, and neutrophil congestion. An anti-histone antibody could reduce these changes and protect mice from histone-induced lethality. Conclusions: This study elucidates a new mechanism for acute lung injury after severe trauma and proposes that circulating histones are viable therapeutic targets for improving survival

Circulating hematopoietic progenitors and CD34+ cells predicted successful hematopoietic stem cell harvest in myeloma and lymphoma patients: experiences from a single institution

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Yu JT

2016-02-01

Full Text Available Jui-Ting Yu,1,2,* Shao-Bin Cheng,3,* Youngsen Yang,1 Kuang-Hsi Chang,4 Wen-Li Hwang,1 Chieh-Lin Jerry Teng,1,5,6 1Division of Hematology/Medical Oncology, Department of Medicine, Taichung Veterans General Hospital, 2Division of Hematology/Medical Oncology, Tungs' Taichung MetroHarbor Hospital, 3Division of General Surgery, Department of Surgery, 4Department of Medical Research and Education, Taichung Veterans General Hospital, 5Department of Life Science, Tunghai University, 6School of Medicine, Chung Shan Medical University, Taichung, Taiwan, Republic of China *These authors contributed equally to this work Background: Previous studies have shown that the numbers of both circulating hematopoietic progenitor cell (HPC and CD34+ cell are positively correlated with CD34+ cell harvest yield. However, the minimal numbers of both circulating HPCs and CD34+ cells required for performing an efficient hematopoietic stem cell (HSC harvest in lymphoma and myeloma patients have not been defined in our institution. Patients and methods: Medical records of 50 lymphoma and myeloma patients undergoing peripheral blood HSC harvest in our institution were retrospectively reviewed. The minimal and optimal HSC harvest yield required for the treatment was considered to be ≥2×106 CD34+ cells/kg and ≥5×106 CD34+ cells/kg, respectively. Results: The minimally required or optimal HSC yield obtained was not influenced by age (≥60 years, sex, underlying malignancies, disease status, multiple rounds of chemotherapy, or history of radiotherapy. The numbers of both circulating HPC and CD34+ cell were higher in patients with minimally required HSC yields (P=0.000 for HPC and P=0.000 for CD34+ cell and also in patients with optimal HSC yields (P=0.011 for HPC and P=0.006 for CD34+ cell. The cell count cutoff for obtaining minimally required HSC harvest was determined to be 20/mm3 for HPCs and 10/mm3 for CD34+ cells. Furthermore, the cell count cutoff for obtaining

Chronic administration of the probiotic kefir improves the endothelial function in spontaneously hypertensive rats.

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Friques, Andreia G F; Arpini, Clarisse M; Kalil, Ieda C; Gava, Agata L; Leal, Marcos A; Porto, Marcella L; Nogueira, Breno V; Dias, Ananda T; Andrade, Tadeu U; Pereira, Thiago Melo C; Meyrelles, Silvana S; Campagnaro, Bianca P; Vasquez, Elisardo C

2015-12-30

recruitment of endothelial progenitor cells was decreased in the non-treated SHR and partially restored by kefir treatment. Kefir treatment for 60 days was able to improve the endothelial function in SHR by partially restoring the ROS/NO imbalance and the endothelial architecture due to endothelial progenitor cells recruitment.

Differential Impact of Acute High-Intensity Exercise on Circulating Endothelial Microparticles and Insulin Resistance between Overweight/Obese Males and Females

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Durrer, Cody; Robinson, Emily; Wan, Zhongxiao; Martinez, Nic; Hummel, Michelle L.; Jenkins, Nathan T.; Kilpatrick, Marcus W.; Little, Jonathan P.

2015-01-01

Background An acute bout of exercise can improve endothelial function and insulin sensitivity when measured on the day following exercise. Our aim was to compare acute high-intensity continuous exercise (HICE) to high-intensity interval exercise (HIIE) on circulating endothelial microparticles (EMPs) and insulin sensitivity in overweight/obese men and women. Methods Inactive males (BMI = 30 ± 3, 25 ± 6 yr, n = 6) and females (BMI = 28 ± 2, 21 ± 3 yr, n = 7) participated in three experimental trials in a randomized counterbalanced crossover design: 1) No exercise control (Control); 2) HICE (20 min cycling @ just above ventilatory threshold); 3) HIIE (10 X 1-min @ ∼90% peak aerobic power). Exercise conditions were matched for external work and diet was controlled post-exercise. Fasting blood samples were obtained ∼18 hr after each condition. CD62E+ and CD31+/CD42b- EMPs were assessed by flow cytometry and insulin resistance (IR) was estimated by homeostasis model assessment (HOMA-IR). Results There was a significant sex X exercise interaction for CD62E+ EMPs, CD31+/CD42b- EMPs, and HOMA-IR (all Pexercise type. There was a significant increase in HOMA-IR in males but a decrease in females following HIIE compared to Control (Pobese males and females appear to respond differently to acute bouts of high-intensity exercise. A single session of HICE and HIIE reduced circulating EMPs measured on the morning following exercise in males but in females CD62E+ EMPs were increased following HICE. Next day HOMA-IR paradoxically increased in males but was reduced in females following HIIE. Future research is needed to investigate mechanisms responsible for potential differential responses between males and females. PMID:25710559

Constitutive production and thrombin-induced release of vascular endothelial growth factor by human megakaryocytes and platelets

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Möhle, Robert; Green, David; Moore, Malcolm A. S.; Nachman, Ralph L.; Rafii, Shahin

1997-01-01

We have shown that coculture of bone marrow microvascular endothelial cells with hematopoietic progenitor cells results in proliferation and differentiation of megakaryocytes. In these long-term cultures, bone marrow microvascular endothelial cell monolayers maintain their cellular integrity in the absence of exogenous endothelial growth factors. Because this interaction may involve paracrine secretion of cytokines, we evaluated megakaryocytic cells for secretion of vascular endothelial growth factor (VEGF). Megakaryocytes (CD41a+) were generated by ex vivo expansion of hematopoietic progenitor cells with kit-ligand and thrombopoietin for 10 days and further purified with immunomagnetic microbeads. Using reverse transcription–PCR, we showed that megakaryocytic cell lines (Dami, HEL) and purified megakaryocytes expressed mRNA of the three VEGF isoforms (121, 165, and 189 amino acids). Large quantities of VEGF (>1 ng/106 cells/3 days) were detected in the supernatant of Dami cells, ex vivo-generated megakaryocytes, and CD41a+ cells isolated from bone marrow. The constitutive secretion of VEGF by CD41a+ cells was stimulated by growth factors of the megakaryocytic lineage (interleukin 3, thrombopoietin). Western blotting of heparin–Sepharose-enriched supernatant mainly detected the isoform VEGF165. In addition, immunohistochemistry showed intracytoplasmic VEGF in polyploid megakaryocytes. Thrombin stimulation of megakaryocytes and platelets resulted in rapid release of VEGF within 30 min. We conclude that human megakaryocytes produce and secrete VEGF in an inducible manner. Within the bone marrow microenvironment, VEGF secreted by megakaryocytes may contribute to the proliferation of endothelial cells. VEGF delivered to sites of vascular injury by activated platelets may initiate angiogenesis. PMID:9012841

Efficient MRI labeling of endothelial progenitor cells: design of thiolated surface stabilized superparamagnetic iron oxide nanoparticles.

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Shahnaz, Gul; Kremser, Christian; Reinisch, Andreas; Vetter, Anja; Laffleur, Flavia; Rahmat, Deni; Iqbal, Javed; Dünnhaupt, Sarah; Salvenmoser, Willi; Tessadri, Richard; Griesser, Ulrich; Bernkop-Schnürch, Andreas

2013-11-01

The aim of this study was to design thiolated surface stabilized superparamagnetic iron oxide nanoparticles (TSS-SPIONs) for efficient internalization with high MRI sensitivity. TSS-SPIONs were developed by chelation between thiolated chitosan-thioglycolic acid (chitosan-TGA) hydrogel and iron ions (Fe(2+)/Fe(3+)). Likely, unmodified chitosan hydrogel SPIONs (UC-SPIONs) and uncoated SPIONs were used as control. Moreover, TSS-SPIONs were investigated regarding to their iron core size, hydrodynamic diameter, zeta potential, iron contents, molar relaxivities (r1 and r2), and cellular internalization. TSS-SPIONs demonstrated an iron oxide core diameter (crystallite size by XRD) of 3.1 ± 0.02 nm, a hydrodynamic diameter of 94 ± 20 nm, a zeta potential of +21 ± 5 mV, and an iron content of 3.6 ± 0.9 mg/mL. In addition, internalization of TSS-SPIONs into human endothelial progenitor cells (EPC) from umbilical cord blood was more than threefold and 17-fold higher in contrast to UC-SPIONs and SPIONs, respectively. With twofold lower incubation iron concentration of TSS-SPIONs, more than threefold higher internalization was achieved as compared to Resovist®. Also, cell viability of more than 90% was observed in the presence of TSS-SPIONs after 24h. The molar MR relaxivities (r2) value at 1.5 T was threefold higher than that of Resovist® and demonstrated that TSS-SPIONs have the potential as very effective T2 contrast-enhancement agent. According to these findings, TSS-SPIONs with efficient internalization, lower cytotoxicity, and high MRI sensitivity seem to be promising for cell tracking. Copyright © 2013 Elsevier B.V. All rights reserved.

Chronic congestive heart failure is associated with a phenotypic shift of intramyocardial endothelial cells

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Marijianowski, M. M.; van Laar, M.; Bras, J.; Becker, A. E.

1995-01-01

There is evidence that patients with chronic congestive heart failure have endothelial cell-related abnormalities of the peripheral circulation and the coronary microvasculature. For that reason, we have studied the phenotypic expression of endothelial cells in hearts of patients with congestive

Direct Cell-Cell Contact between Mesenchymal Stem Cells and Endothelial Progenitor Cells Induces a Pericyte-Like Phenotype In Vitro

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Markus Loibl

2014-01-01

Full Text Available Tissue engineering techniques for the regeneration of large bone defects require sufficient vascularisation of the applied constructs to ensure a sufficient supply of oxygen and nutrients. In our previous work, prevascularised 3D scaffolds have been successfully established by coculture of bone marrow derived stem cells (MSCs and endothelial progenitor cells (EPCs. We identified stabilising pericytes (PCs as part of newly formed capillary-like structures. In the present study, we report preliminary data on the interactions between MSCs and EPCs, leading to the differentiation of pericyte-like cells. MSCs and EPCs were seeded in transwell cultures, direct cocultures, and single cultures. Cells were cultured for 10 days in IMDM 10% FCS or IMDM 5% FCS 5% platelet lysate medium. Gene expression of PC markers, CD146, NG2, αSMA, and PDGFR-β, was analysed using RT-PCR at days 0, 3, 7, and 10. The upregulation of CD146, NG2, and αSMA in MSCs in direct coculture with EPCs advocates the MSCs’ differentiation towards a pericyte-like phenotype in vitro. These results suggest that pericyte-like cells derive from MSCs and that cell-cell contact with EPCs is an important factor for this differentiation process. These findings emphasise the concept of coculture strategies to promote angiogenesis for cell-based tissue engineered bone grafts.

Aerobic exercise modulation of mental stress-induced responses in cultured endothelial progenitor cells from healthy and metabolic syndrome subjects.

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Rocha, Natalia G; Sales, Allan R K; Miranda, Renan L; Silva, Mayra S; Silva, Jemima F R; Silva, Bruno M; Santos, Aline A; Nóbrega, Antonio C L

2015-02-15

Numerous studies have demonstrated that exercise acutely prevents the reduction in flow-mediated dilation induced by mental stress in subjects with metabolic syndrome (MetS). However, it is unknown whether a similar effect occurs in endothelial progenitors cells (EPCs). This study investigated whether exercise protects from the deleterious effect of mental stress on cultured EPCs in healthy subjects and those with MetS. Ten healthy subjects (aged 31±2) and ten subjects with MetS (aged 36±2) were enrolled. Subjects underwent a mental stress test, followed immediately by either 40 min of leg cycling or rest across two randomized sessions: mental stress+non-exercise control (MS) and mental stress+exercise (MS+EXE). The Stroop Color-Word Test was used to elicit mental stress. Blood samples were drawn at baseline and following sessions to isolate mononuclear cells. These cells were cultured in fibronectin-coated plates for seven days, and EPCs were identified by immunofluorescence (acLDL(+)/ UEA-I Lectin(+)). All subjects presented similar increases in mean blood pressure and heart rate during the mental stress test (P0.05). The EPC response to MS and MS+EXE was increased in healthy subjects, whereas it was decreased in subjects with MetS (Pexercise session increased EPCs in healthy subjects but did not prevent the EPC reduction induced by mental stress among subjects with MetS. © 2015.

[Effect of simvastatin on inducing endothelial progenitor cells homing and promoting bone defect repair].

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Song, Quansheng; Wang, Lingying; Zhu, Jinglin; Han, Xiaoguang; Li, Xu; Yang, Yanlin; Sun, Yan; Song, Chunli

2010-09-01

To investigate the effect of simvastatin on inducing endothelial progenitor cells (EPCs) homing and promoting bone defect repair, and to explore the mechanism of local implanting simvastatin in promoting bone formation. Simvastatin (50 mg) compounded with polylactic acid (PLA, 200 mg) or only PLA (200 mg) was dissolved in acetone (1 mL) to prepare implanted materials (Simvastatin-PLA material, PLA material). EPCs were harvested from bone marrow of 2 male rabbits and cultured with M199; after identified by immunohistochemistry, the cell suspension of EPCs at the 3rd generation (2 x 10(6) cells/mL) was prepared and transplanted into 12 female rabbits through auricular veins (2 mL). After 3 days, the models of cranial defect with 15 cm diameter were made in the 12 female rabbits. And the defects were repaired with Simvastatin-PLA materials (experimental group, n=6) and PLA materials (control group, n=6), respectively. The bone repair was observed after 8 weeks of operation by gross appearance, X-ray film, and histology; gelatin-ink perfusion and HE staining were used to show the new vessels formation in the defect. Fluorescence in situ hybridization (FISH) was performed to show the EPCs homing at the defect site. All experimental animals of 2 groups survived to the end of the experiment. After 8 weeks in experimental group, new bone formation was observed in the bone defect by gross and histology, and an irregular, hyperdense shadow by X-ray film; no similar changes were observed in control group. FISH showed that the male EPC containing Y chromosome was found in the wall of new vessels in the defect of experimental group, while no male EPC containing Y chromosome was found in control group. The percentage of new bone formation in defect area was 91.63% +/- 4.07% in experimental group and 59.45% +/- 5.43% in control group, showing significant difference (P < 0.05). Simvastatin can promote bone defect repair, and its mechanism is probably associated with inducing EPCs

Exercise training-induced different improvement profile of endothelial progenitor cells function in mice with or without myocardial infarction.

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Guo, Yuan; Peng, Ran; Liu, Qiong; Xu, Danyan

2016-10-15

Neovascularization in response to ischemia after myocardial infarction (MI) has been widely considered as being initiated by endothelial progenitor cells (EPCs). Well-documented evidences in recent years have proved exercise training (ET) improving EPC function. However, whether ET-induced improvement of EPC function under or without ischemic state is different has not been reported. Mice performed ET following an exercise prescription 1week after MI or non-MI surgery respectively. Bone marrow-derived EPCs were isolated at 0day, 3days, 1week, 2weeks, 4weeks, and 8weeks of ET. After 7days cultivation, EPC functions including proliferation, adhesion, migration, and in vitro angiogenesis were measured. AKT/glycogen synthase kinase 3β (GSK3β) signaling pathway was tested by western blotting. EPC function in mice underwent non-MI surgery was attenuated overtime, while ET ameliorated this tendency. EPC function was peaked at 4weeks ET in non-MI surgery mice and maintained with an extended exercise time. Besides, simple ischemia was sufficient to enhanced EPC function, with a maximum at 2weeks of MI surgery. In MI mice, ET further improved EPC function and achieved peak at 2weeks exercise. Furthermore, AKT/GSK3β signaling pathway activation was consistent with EPC function change after ischemia, which was further promoted by 4weeks exercise. ET significantly increased EPC function in mice both with and without MI, but the time points of peak function were different. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Pluripotent cell models of fanconi anemia identify the early pathological defect in human hemoangiogenic progenitors.

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Suzuki, Naoya M; Niwa, Akira; Yabe, Miharu; Hira, Asuka; Okada, Chihiro; Amano, Naoki; Watanabe, Akira; Watanabe, Ken-Ichiro; Heike, Toshio; Takata, Minoru; Nakahata, Tatsutoshi; Saito, Megumu K

2015-04-01

Fanconi anemia (FA) is a disorder of genomic instability characterized by progressive bone marrow failure (BMF), developmental abnormalities, and an increased susceptibility to cancer. Although various consequences in hematopoietic stem/progenitor cells have been attributed to FA-BMF, the quest to identify the initial pathological event is still ongoing. To address this issue, we established induced pluripotent stem cells (iPSCs) from fibroblasts of six patients with FA and FANCA mutations. An improved reprogramming method yielded iPSC-like colonies from all patients, and iPSC clones were propagated from two patients. Quantitative evaluation of the differentiation ability demonstrated that the differentiation propensity toward the hematopoietic and endothelial lineages is already defective in early hemoangiogenic progenitors. The expression levels of critical transcription factors were significantly downregulated in these progenitors. These data indicate that the hematopoietic consequences in FA patients originate from the early hematopoietic stage and highlight the potential usefulness of iPSC technology for elucidating the pathogenesis of FA-BMF. ©AlphaMed Press.

Arterial Injury and Endothelial Repair: Rapid Recovery of Function after Mechanical Injury in Healthy Volunteers

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Lindsey Tilling

2014-01-01

Full Text Available Objective. Previous studies suggest a protracted course of recovery after mechanical endothelial injury; confounders may include degree of injury and concomitant endothelial dysfunction. We sought to define the time course of endothelial function recovery using flow-mediated dilation (FMD, after ischaemia-reperfusion (IR and mechanical injury in patients and healthy volunteers. The contribution of circulating CD133+/CD34+/VEGFR2+ “endothelial progenitor” (EPC or repair cells to endothelial repair was also examined. Methods. 28 healthy volunteers aged 18–35 years underwent transient forearm ischaemia induced by cuff inflation around the proximal biceps and radial artery mechanical injury induced by inserting a wire through a cannula. A more severe mechanical injury was induced using an arterial sheath and catheter inserted into the radial artery of 18 patients undergoing angiography. Results. IR and mechanical injury produced immediate impairment of FMD (from 6.5 ± 1.2% to 2.9 ± 2.2% and from 7.4 ± 2.3% to 1.5 ± 1.6% for IR and injury, resp., each P<0.001 but recovered within 6 hours and 2 days, respectively. FMD took up to 4 months to recover in patients. Circulating EPC did not change significantly during the injury/recovery period in all subjects. Conclusions. Recovery of endothelial function after IR and mechanical injury is rapid and not associated with a change in circulating EPC.

Far infra-red therapy promotes ischemia-induced angiogenesis in diabetic mice and restores high glucose-suppressed endothelial progenitor cell functions

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Huang Po-Hsun

2012-08-01

Full Text Available Abstract Background Far infra-red (IFR therapy was shown to exert beneficial effects in cardiovascular system, but effects of IFR on endothelial progenitor cell (EPC and EPC-related vasculogenesis remain unclear. We hypothesized that IFR radiation can restore blood flow recovery in ischemic hindlimb in diabetic mice by enhancement of EPCs functions and homing process. Materials and methods Starting at 4 weeks after the onset of diabetes, unilateral hindlimb ischemia was induced in streptozotocine (STZ-induced diabetic mice, which were divided into control and IFR therapy groups (n = 6 per group. The latter mice were placed in an IFR dry sauna at 34°C for 30 min once per day for 5 weeks. Results Doppler perfusion imaging demonstrated that the ischemic limb/normal side blood perfusion ratio in the thermal therapy group was significantly increased beyond that in controls, and significantly greater capillary density was seen in the IFR therapy group. Flow cytometry analysis showed impaired EPCs (Sca-1+/Flk-1+ mobilization after ischemia surgery in diabetic mice with or without IFR therapy (n = 6 per group. However, as compared to those in the control group, bone marrow-derived EPCs differentiated into endothelial cells defined as GFP+/CD31+ double-positive cells were significantly increased in ischemic tissue around the vessels in diabetic mice that received IFR radiation. In in-vitro studies, cultured EPCs treated with IFR radiation markedly augmented high glucose-impaired EPC functions, inhibited high glucose-induced EPC senescence and reduced H2O2 production. Nude mice received human EPCs treated with IFR in high glucose medium showed a significant improvement in blood flow recovery in ischemic limb compared to those without IFR therapy. IFR therapy promoted blood flow recovery and new vessel formation in STZ-induced diabetic mice. Conclusions Administration of IFR therapy promoted collateral flow recovery and new vessel formation in STZ

Downregulation of microRNA-130a contributes to endothelial progenitor cell dysfunction in diabetic patients via its target Runx3.

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Shu Meng

Full Text Available Dysfunction of endothelial progenitor cells (EPCs contributes to diabetic vascular disease. MicroRNAs (miRs have emerged as key regulators of diverse cellular processes including angiogenesis. We recently reported that miR-126, miR-130a, miR-21, miR-27a, and miR-27b were downregulated in EPCs from type II diabetes mellitus (DM patients, and downregulation of miR-126 impairs EPC function. The present study further explored whether dysregulated miR-130a were also related to EPC dysfunction. EPCs were cultured from peripheral blood mononuclear cells of diabetic patients and healthy controls. Assays on EPC function (proliferation, migration, differentiation, apoptosis, and colony and tubule formation were performed. Bioinformatics analyses were used to identify the potential targets of miR-130a in EPCs. Gene expression of miR-103a and Runx3 was measured by real-time PCR, and protein expression of Runx3, extracellular signal-regulated kinase (ERK, vascular endothelial growth factor (VEGF and Akt was measured by Western blotting. Runx3 promoter activity was measured by luciferase reporter assay. A miR-130a inhibitor or mimic and lentiviral vectors expressing miR-130a, or Runx3, or a short hairpin RNA targeting Runx3 were transfected into EPCs to manipulate miR-130a and Runx3 levels. MiR-130a was decreased in EPCs from DM patients. Anti-miR-130a inhibited whereas miR-130a overexpression promoted EPC function. miR-130a negatively regulated Runx3 (mRNA, protein and promoter activity in EPCs. Knockdown of Runx3 expression enhanced EPC function. MiR-130a also upregulated protein expression of ERK/VEGF and Akt in EPCs. In conclusion, miR-130a plays an important role in maintaining normal EPC function, and decreased miR-130a in EPCs from DM contributes to impaired EPC function, likely via its target Runx3 and through ERK/VEGF and Akt pathways.

Activation of Endothelial Nitric Oxide (eNOS Occurs through Different Membrane Domains in Endothelial Cells.

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Jason Tran

Full Text Available Endothelial cells respond to a large range of stimuli including circulating lipoproteins, growth factors and changes in haemodynamic mechanical forces to regulate the activity of endothelial nitric oxide synthase (eNOS and maintain blood pressure. While many signalling pathways have been mapped, the identities of membrane domains through which these signals are transmitted are less well characterized. Here, we manipulated bovine aortic endothelial cells (BAEC with cholesterol and the oxysterol 7-ketocholesterol (7KC. Using a range of microscopy techniques including confocal, 2-photon, super-resolution and electron microscopy, we found that sterol enrichment had differential effects on eNOS and caveolin-1 (Cav1 colocalisation, membrane order of the plasma membrane, caveolae numbers and Cav1 clustering. We found a correlation between cholesterol-induced condensation of the plasma membrane and enhanced high density lipoprotein (HDL-induced eNOS activity and phosphorylation suggesting that cholesterol domains, but not individual caveolae, mediate HDL stimulation of eNOS. Vascular endothelial growth factor (VEGF-induced and shear stress-induced eNOS activity was relatively independent of membrane order and may be predominantly controlled by the number of caveolae on the cell surface. Taken together, our data suggest that signals that activate and phosphorylate eNOS are transmitted through distinct membrane domains in endothelial cells.

Angiogenesis gene expression in murine endothelial cells during post-pneumonectomy lung growth

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Konerding Moritz A

2011-07-01

Full Text Available Abstract Although blood vessel growth occurs readily in the systemic bronchial circulation, angiogenesis in the pulmonary circulation is rare. Compensatory lung growth after pneumonectomy is an experimental model with presumed alveolar capillary angiogenesis. To investigate the genes participating in murine neoalveolarization, we studied the expression of angiogenesis genes in lung endothelial cells. After left pneumonectomy, the remaining right lung was examined on days 3, 6, 14 and 21days after surgery and compared to both no surgery and sham thoracotomy controls. The lungs were enzymatically digested and CD31+ endothelial cells were isolated using flow cytometry cell sorting. The transcriptional profile of the CD31+ endothelial cells was assessed using quantitative real-time polymerase chain reaction (PCR arrays. Focusing on 84 angiogenesis-associated genes, we identified 22 genes with greater than 4-fold regulation and significantly enhanced transcription (p

Induced pluripotent stem cell-derived cardiac progenitors differentiate to cardiomyocytes and form biosynthetic tissues.

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Nicolas Christoforou

Full Text Available The mammalian heart has little capacity to regenerate, and following injury the myocardium is replaced by non-contractile scar tissue. Consequently, increased wall stress and workload on the remaining myocardium leads to chamber dilation, dysfunction, and heart failure. Cell-based therapy with an autologous, epigenetically reprogrammed, and cardiac-committed progenitor cell source could potentially reverse this process by replacing the damaged myocardium with functional tissue. However, it is unclear whether cardiac progenitor cell-derived cardiomyocytes are capable of attaining levels of structural and functional maturity comparable to that of terminally-fated cardiomyocytes. Here, we first describe the derivation of mouse induced pluripotent stem (iPS cells, which once differentiated allow for the enrichment of Nkx2-5(+ cardiac progenitors, and the cardiomyocyte-specific expression of the red fluorescent protein. We show that the cardiac progenitors are multipotent and capable of differentiating into endothelial cells, smooth muscle cells and cardiomyocytes. Moreover, cardiac progenitor selection corresponds to cKit(+ cell enrichment, while cardiomyocyte cell-lineage commitment is concomitant with dual expression of either cKit/Flk1 or cKit/Sca-1. We proceed to show that the cardiac progenitor-derived cardiomyocytes are capable of forming electrically and mechanically coupled large-scale 2D cell cultures with mature electrophysiological properties. Finally, we examine the cell progenitors' ability to form electromechanically coherent macroscopic tissues, using a physiologically relevant 3D culture model and demonstrate that following long-term culture the cardiomyocytes align, and form robust electromechanical connections throughout the volume of the biosynthetic tissue construct. We conclude that the iPS cell-derived cardiac progenitors are a robust cell source for tissue engineering applications and a 3D culture platform for pharmacological

Obstructive sleep apnoea syndrome, endothelial function and markers of endothelialization. Changes after CPAP.

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Muñoz-Hernandez, Rocio; Vallejo-Vaz, Antonio J; Sanchez Armengol, Angeles; Moreno-Luna, Rafael; Caballero-Eraso, Candela; Macher, Hada C; Villar, Jose; Merino, Ana M; Castell, Javier; Capote, Francisco; Stiefel, Pablo

2015-01-01

This study tries to assess the endothelial function in vivo using flow-mediated dilatation (FMD) and several biomarkers of endothelium formation/restoration and damage in patients with obstructive sleep apnoea (OSA) syndrome at baseline and after three months with CPAP therapy. Observational study, before and after CPAP therapy. We studied 30 patients with apnoea/hypopnoea index (AHI) >15/h that were compared with themselves after three months of CPAP therapy. FMD was assessed non-invasively in vivo using the Laser-Doppler flowmetry. Circulating cell-free DNA (cf-DNA) and microparticles (MPs) were measured as markers of endothelial damage and the vascular endothelial growth factor (VEGF) was determined as a marker of endothelial restoration process. After three month with CPAP, FMD significantly increased (1072.26 ± 483.21 vs. 1604.38 ± 915.69 PU, pDNA and MPs significantly decreased (187.93 ± 115.81 vs. 121.28 ± 78.98 pg/ml, p<0.01, and 69.60 ± 62.60 vs. 39.82 ± 22.14 U/μL, p<0.05, respectively) and VEGF levels increased (585.02 ± 246.06 vs. 641.11 ± 212.69 pg/ml, p<0.05). These changes were higher in patients with more severe disease. There was a relationship between markers of damage (r = -0.53, p<0.005) but not between markers of damage and restoration, thus suggesting that both types of markers should be measured together. CPAP therapy improves FMD. This improvement may be related to an increase of endothelial restoration process and a decrease of endothelial damage.

Blood on the tracks: hematopoietic stem cell-endothelial cell interactions in homing and engraftment.

Science.gov (United States)

Perlin, Julie R; Sporrij, Audrey; Zon, Leonard I

2017-08-01

Cells of the hematopoietic system undergo rapid turnover. Each day, humans require the production of about one hundred billion new blood cells for proper function. Hematopoietic stem cells (HSCs) are rare cells that reside in specialized niches and are required throughout life to produce specific progenitor cells that will replenish all blood lineages. There is, however, an incomplete understanding of the molecular and physical properties that regulate HSC migration, homing, engraftment, and maintenance in the niche. Endothelial cells (ECs) are intimately associated with HSCs throughout the life of the stem cell, from the specialized endothelial cells that give rise to HSCs, to the perivascular niche endothelial cells that regulate HSC homeostasis. Recent studies have dissected the unique molecular and physical properties of the endothelial cells in the HSC vascular niche and their role in HSC biology, which may be manipulated to enhance hematopoietic stem cell transplantation therapies.

Functional activities of receptors for tumor necrosis factor-alpha on human vascular endothelial cells.

NARCIS (Netherlands)

Paleolog, E.M.; Delasalle, S.A.; Buurman, W.A.; Feldmann, M.

1994-01-01

Tumor necrosis factor-alpha (TNF-alpha) plays a critical role in the control of endothelial cell function and hence in regulating traffic of circulating cells into tissues in vivo. Stimulation of endothelial cells in vitro by TNF-alpha increases the surface expression of leukocyte adhesion

Maternal biomarkers of endothelial dysfunction and preterm delivery.

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Xinhua Chen

Full Text Available Endothelial dysfunction is key to the development of atherosclerosis. Preterm delivery foreshadows later maternal cardiovascular disease (CVD, but it is not known if endothelial dysfunction also occurs. We prospectively measured circulating biomarkers of endothelial dysfunction in pregnant women with preterm or term delivery.We conducted a case-control study nested within a large prospective epidemiological study of young, generally healthy pregnant women. Women who delivered preterm (<37 completed weeks gestation, n = 240 and controls who delivered at term (n = 439 were included. Pregnancies complicated by preeclampsia were analyzed separately. Circulating endothelial dysfunction biomarkers included soluble intercellular adhesion molecule-1 (sICAM-1, vascular cell adhesion molecule-1 (sVCAM-1 and soluble E-selectin (sE-selectin.Elevated levels of sICAM-1 and sVCAM-1 were positively associated with preterm delivery independent of usual risk factors. At entry (∼16 wks, the adjusted odds ratio (AOR was 1.73 (95% confidence interval (CI 1.09-2.74 for the highest quartile of sICAM-1 versus the lowest quartile and for sVCAM-1 the AOR was 2.17 (95% CI 1.36-3.46. When analysis was limited to cases with a spontaneous preterm delivery, the results were unchanged. Similar results were obtained for the 3rd trimester (∼30 wks. Elevated sE-selectin was increased only in preterm delivery complicated by preeclampsia; risk was increased at entry (AOR 2.32, 95% CI 1.22-4.40 and in the 3rd trimester (AOR 3.37, 95% CI 1.78-6.39.Impaired endothelial function as indicated by increased levels of soluble molecules commonly secreted by endothelial cells is a pathogenic precursor to CVD that is also present in women with preterm delivery. Our findings underscore the need for follow-up studies to determine if improving endothelial function prevents later CVD risk in women.

Mature and progenitor endothelial cells perform angiogenesis also under protease inhibition: the amoeboid angiogenesis.

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Chillà, Anastasia; Margheri, Francesca; Biagioni, Alessio; Del Rosso, Mario; Fibbi, Gabriella; Laurenzana, Anna

2018-04-03

Controlling vascular growth is a challenging aim for the inhibition of tumor growth and metastasis. The amoeboid and mesenchymal types of invasiveness are two modes of migration interchangeable in cancer cells: the Rac-dependent mesenchymal migration requires the activity of proteases; the Rho-ROCK-dependent amoeboid motility is protease-independent and has never been described in endothelial cells. A cocktail of physiologic inhibitors (Ph-C) of serine-proteases, metallo-proteases and cysteine-proteases, mimicking the physiological environment that cells encounter during their migration within the angiogenesis sites was used to induce amoeboid style migration of Endothelial colony forming cells (ECFCs) and mature endothelial cells (ECs). To evaluate the mesenchymal-ameboid transition RhoA and Rac1 activation assays were performed along with immunofluorescence analysis of proteins involved in cytoskeleton organization. Cell invasion was studied in Boyden chambers and Matrigel plug assay for the in vivo angiogenesis. In the present study we showed in both ECFCs and ECs, a decrease of activated Rac1 and an increase of activated RhoA upon shifting of cells to the amoeboid conditions. In presence of Ph-C inhibitors both cell lines acquired a round morphology and Matrigel invasion was greatly enhanced with respect to that observed in the absence of protease inhibition. We also observed that the urokinase-plasminogen-activator (uPAR) receptor silencing and uPAR-integrin uncoupling with the M25 peptide abolished both mesenchymal and amoeboid angiogenesis of ECFCs and ECs in vitro and in vivo, indicating a role of the uPAR-integrin-actin axis in the regulation of amoeboid angiogenesis. Furthermore, under amoeboid conditions endothelial cells seem to be indifferent to VEGF stimulation, which induces an amoeboid signaling pattern also in mesenchymal conditions. Here we first provide a data set disclosing that endothelial cells can move and differentiate into vascular

How to utilize Ca²⁺ signals to rejuvenate the repairative phenotype of senescent endothelial progenitor cells in elderly patients affected by cardiovascular diseases: a useful therapeutic support of surgical approach?

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Moccia, Francesco; Dragoni, Silvia; Cinelli, Mariapia; Montagnani, Stefania; Amato, Bruno; Rosti, Vittorio; Guerra, Germano; Tanzi, Franco

2013-01-01

Endothelial dysfunction or loss is the early event that leads to a host of severe cardiovascular diseases, such as atherosclerosis, hypertension, brain stroke, myocardial infarction, and peripheral artery disease. Ageing is regarded among the most detrimental risk factor for vascular endothelium and predisposes the subject to atheroscleorosis and inflammatory states even in absence of traditional comorbid conditions. Standard treatment to restore blood perfusion through stenotic arteries are surgical or endovascular revascularization. Unfortunately, ageing patients are not the most amenable candidates for such interventions, due to high operative risk or unfavourable vascular involvement. It has recently been suggested that the transplantation of autologous bone marrow-derived endothelial progenitor cells (EPCs) might constitute an alternative and viable therapeutic option for these individuals. Albeit pre-clinical studies demonstrated the feasibility of EPC-based therapy to recapitulate the diseased vasculature of young and healthy animals, clinical studies provided less impressive results in old ischemic human patients. One hurdle associated to this kind of approach is the senescence of autologous EPCs, which are less abundant in peripheral blood and display a reduced pro-angiogenic activity. Conversely, umbilical cord blood (UCB)-derived EPCs are more suitable for cellular therapeutics due to their higher frequency and sensitivity to growth factors, such as vascular endothelial growth factor (VEGF). An increase in intracellular Ca(2+) concentration is central to EPC activation by VEGF. We have recently demonstrated that the Ca(2+) signalling machinery driving the oscillatory Ca(2+) response to this important growth factor is different in UCB-derived EPCs as compared to their peripheral counterparts. In particular, we focussed on the so-called endothelial colony forming cells (ECFCs), which are the only EPC population belonging to the endothelial lineage and able

Defibrotide in combination with granulocyte colony-stimulating factor significantly enhances the mobilization of primitive and committed peripheral blood progenitor cells in mice.

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Carlo-Stella, Carmelo; Di Nicola, Massimo; Magni, Michele; Longoni, Paolo; Milanesi, Marco; Stucchi, Claudio; Cleris, Loredana; Formelli, Franca; Gianni, Massimo A

2002-11-01

Defibrotide is a polydeoxyribonucleotide, which significantly reduces the expression of adhesion molecules on endothelial cells. We investigated the activity of Defibrotide alone or in combination with recombinant human granulocyte colony-stimulating factor (rhG-CSF) to mobilize peripheral blood progenitor cells (PBPCs) in BALB/c mice. A 5-day treatment with Defibrotide alone (1-15 mg/mouse/day) had no effect on WBC counts, frequencies and absolute numbers of total circulating colony-forming cells (CFCs), i.e., granulocyte-macrophage colony-forming units, erythroid burst-forming units, and multilineage colony-forming units. As compared with mock-injected mice, administration of rhG-CSF alone (5 micro g/mouse/day) for 5 days significantly (P Defibrotide (15 mg/mouse/day) and rhG-CSF significantly (P Defibrotide plus rhG-CSF resulted in a significant increase (P Defibrotide/rhG-CSF-mobilized mononuclear cells rescued 43% and 71% of recipient mice, respectively. Experiments of CFC homing performed in lethally irradiated or nonirradiated recipients showed that marrow homing of transplanted PBPCs was reduced by 3-fold in Defibrotide-treated animals as compared with mock-injected mice (P Defibrotide might be because of an effect on PBPC trafficking. In conclusion, our data demonstrate that Defibrotide synergizes with rhG-CSF and significantly increases the mobilization of a broad spectrum of PBPCs, including primitive and committed progenitor cells. These data might have relevant implications for autologous and allogeneic anticancer therapy in humans.

Construction of a multifunctional coating consisting of phospholipids and endothelial progenitor cell-specific peptides on titanium substrates

Energy Technology Data Exchange (ETDEWEB)

Chen, Huiqing; Li, Xiaojing [Key Lab. of Advanced Technology for Materials of Education Ministry, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031 (China); Zhao, Yuancong, E-mail: zhaoyc7320@163.com [Key Lab. of Advanced Technology for Materials of Education Ministry, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031 (China); Li, Jingan; Chen, Jiang [Key Lab. of Advanced Technology for Materials of Education Ministry, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031 (China); Yang, Ping, E-mail: yangping8@263.net [Key Lab. of Advanced Technology for Materials of Education Ministry, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031 (China); Maitz, Manfred F. [Key Lab. of Advanced Technology for Materials of Education Ministry, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031 (China); Max Bergmann Center of Biomaterials Dresden, Leibniz of Polymer Research Dresden, 01069 Dresden (Germany); Huang, Nan [Key Lab. of Advanced Technology for Materials of Education Ministry, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031 (China)

2015-08-30

Graphical abstract: The phospholipid groups of PMMDP can inhibit platele adhesion, and the EPCs-specific peptide of the PMMDP showed special recognition and capture for EPCs. The catechol groups of PMMDP play a critical role as molecular anchor for balancing the binding between the coating and the substrate. - Highlights: • The uniform coating of PMMDP can be constructed on titanium surface successfully through the catechol groups. • The phospholipid groups of PMMDP can inhibit platele adhesion, fibrinogen denaturation and improve the hydrophilicity of substrate. • The EPCs-specific peptide of the PMMDP showed special recognition and capture for EPCs. - Abstract: A phospholipid/peptide polymer (PMMDP) with phosphorylcholine groups, endothelial progenitor cell (EPC)-specific peptides and catechol groups was anchored onto a titanium (Ti) surface to fabricate a biomimetic multifunctional surface. The PMMDP coating was characterized by X-ray photoelectron spectroscopy (XPS), water contact angle measurements and atomic force microscopy (AFM), respectively. The amount of PMMDP coating on the Ti surface was quantified by using the quartz crystal microbalance with dissipation (QCM-D). Interactions between blood components and the coated and bare Ti substrates were evaluated by platelet adhesion and activation assays and fibrinogen denaturation test using platelet rich plasma (PRP). The results revealed that the PMMDP-modified surface inhibited fibrinogen denaturation and reduced platelet adhesion and activation. EPC cell culture on the PMMDP-modified surface showed increased adhesion and proliferation of EPCs when compared to the cells cultured on untreated Ti surface. The inhibition of fibrinogen denaturation and platelet adhesion and support of EPCs attachment and proliferation indicated that this coating might be beneficial for future applications in blood-contacting implants, such as vascular stents.

Pioglitazone Improves In Vitro Viability and Function of Endothelial Progenitor Cells from Individuals with Impaired Glucose Tolerance

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Spigoni, Valentina; Picconi, Angela; Cito, Monia; Ridolfi, Valentina; Bonomini, Sabrina; Casali, Chiara; Zavaroni, Ivana; Gnudi, Luigi; Metra, Marco; Dei Cas, Alessandra

2012-01-01

Background Evidence suggests that the PPARγ-agonist insulin sensitizer pioglitazone, may provide potential beneficial cardiovascular (CV) effects beyond its anti-hyperglycaemic function. A reduced endothelial progenitor cell (EPC) number is associated with impaired glucose tolerance (IGT) or diabetes, conditions characterised by increased CV risk. Aim To evaluate whether pioglitazone can provide benefit in vitro in EPCs obtained from IGT subjects. Materials and Methods Early and late-outgrowth EPCs were obtained from peripheral blood mononuclear cells of 14 IGT subjects. The in vitro effect of pioglitazone (10 µM) with/without PPARγ-antagonist GW9662 (1 µM) was assessed on EPC viability, apoptosis, ability to form tubular-like structures and pro-inflammatory molecule expression. Results Pioglitazone increased early and late-outgrowth EPC viability, with negligible effects on apoptosis. The capacity of EPCs to form tubular-like structures was improved by pioglitazone in early (mean increase 28%; p = 0.005) and late-outgrowth (mean increase 30%; p = 0.037) EPCs. Pioglitazone reduced ICAM-1 and VCAM-1 adhesion molecule expression in both early (p = 0.001 and p = 0.012 respectively) and late-outgrowth (p = 0.047 and p = 0.048, respectively) EPCs. Similarly, pioglitazone reduced TNFα gene and protein expression in both early (p = 0.034;p = 0.022) and late-outgrowth (p = 0.026;p = 0.017) EPCs compared to control. These effects were prevented by incubation with the PPARγ-antagonist GW9662. Conclusion Pioglitazone exerts beneficial effects in vitro on EPCs isolated from IGT subjects, supporting the potential implication of pioglitazone as a CV protective agents. PMID:23139771

Citrus Polyphenol Hesperidin Stimulates Production of Nitric Oxide in Endothelial Cells while Improving Endothelial Function and Reducing Inflammatory Markers in Patients with Metabolic Syndrome

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Rizza, Stefano; Muniyappa, Ranganath; Iantorno, Micaela; Kim, Jeong-a; Chen, Hui; Pullikotil, Philomena; Senese, Nicoletta; Tesauro, Manfredi; Lauro, Davide; Cardillo, Carmine

2011-01-01

Context: Hesperidin, a citrus flavonoid, and its metabolite hesperetin may have vascular actions relevant to their health benefits. Molecular and physiological mechanisms of hesperetin actions are unknown. Objective: We tested whether hesperetin stimulates production of nitric oxide (NO) from vascular endothelium and evaluated endothelial function in subjects with metabolic syndrome on oral hesperidin therapy. Design, Setting, and Interventions: Cellular mechanisms of action of hesperetin were evaluated in bovine aortic endothelial cells (BAEC) in primary culture. A randomized, placebo-controlled, double-blind, crossover trial examined whether oral hesperidin administration (500 mg once daily for 3 wk) improves endothelial function in individuals with metabolic syndrome (n = 24). Main Outcome Measure: We measured the difference in brachial artery flow-mediated dilation between placebo and hesperidin treatment periods. Results: Treatment of BAEC with hesperetin acutely stimulated phosphorylation of Src, Akt, AMP kinase, and endothelial NO synthase to produce NO; this required generation of H2O2. Increased adhesion of monocytes to BAEC and expression of vascular cell adhesion molecule-1 in response to TNF-α treatment was reduced by pretreatment with hesperetin. In the clinical study, when compared with placebo, hesperidin treatment increased flow-mediated dilation (10.26 ± 1.19 vs. 7.78 ± 0.76%; P = 0.02) and reduced concentrations of circulating inflammatory biomarkers (high-sensitivity C-reactive protein, serum amyloid A protein, soluble E-selectin). Conclusions: Novel mechanisms for hesperetin action in endothelial cells inform effects of oral hesperidin treatment to improve endothelial dysfunction and reduce circulating markers of inflammation in our exploratory clinical trial. Hesperetin has vasculoprotective actions that may explain beneficial cardiovascular effects of citrus consumption. PMID:21346065

Obstructive sleep apnoea syndrome, endothelial function and markers of endothelialization. Changes after CPAP.

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Rocio Muñoz-Hernandez

Full Text Available This study tries to assess the endothelial function in vivo using flow-mediated dilatation (FMD and several biomarkers of endothelium formation/restoration and damage in patients with obstructive sleep apnoea (OSA syndrome at baseline and after three months with CPAP therapy.Observational study, before and after CPAP therapy.We studied 30 patients with apnoea/hypopnoea index (AHI >15/h that were compared with themselves after three months of CPAP therapy. FMD was assessed non-invasively in vivo using the Laser-Doppler flowmetry. Circulating cell-free DNA (cf-DNA and microparticles (MPs were measured as markers of endothelial damage and the vascular endothelial growth factor (VEGF was determined as a marker of endothelial restoration process.After three month with CPAP, FMD significantly increased (1072.26 ± 483.21 vs. 1604.38 ± 915.69 PU, p< 0.005 cf-DNA and MPs significantly decreased (187.93 ± 115.81 vs. 121.28 ± 78.98 pg/ml, p<0.01, and 69.60 ± 62.60 vs. 39.82 ± 22.14 U/μL, p<0.05, respectively and VEGF levels increased (585.02 ± 246.06 vs. 641.11 ± 212.69 pg/ml, p<0.05. These changes were higher in patients with more severe disease. There was a relationship between markers of damage (r = -0.53, p<0.005 but not between markers of damage and restoration, thus suggesting that both types of markers should be measured together.CPAP therapy improves FMD. This improvement may be related to an increase of endothelial restoration process and a decrease of endothelial damage.

Plasma factors in severe early-onset preeclampsia do not substantially alter endothelial gene expression in vitro

NARCIS (Netherlands)

Donker, RB; Asgeirsdottir, SA; Gerbens, F; van Pamus, MG; Kallenberg, CGM; Meerman, GJT; Aarnoudse, JG; Molema, G

OBJECTIVE: Systemic endothelial dysfunction is a central feature in the pathophysiology of preeclampsia. Its cell biologic and molecular basis is poorly understood. One leading hypothesis argues that endothelial dysfunction is caused by (at present largely unknown) circulating factors released from

Endothelial progenitor cells in mothers of low-birthweight infants: a link between defective placental vascularization and increased cardiovascular risk?

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King, Thomas F J; Bergin, David A; Kent, Etaoin M; Manning, Fiona; Reeves, Emer P; Dicker, Patrick; McElvaney, Noel G; Sreenan, Seamus; Malone, Fergal D; McDermott, John H

2013-01-01

Offspring birthweight is inversely associated with future maternal cardiovascular mortality, a relationship that has yet to be fully elucidated. Endothelial progenitor cells (EPCs) are thought to play a key role in vasculogenesis, and EPC numbers reflect cardiovascular risk. Our objective was to ascertain whether EPC number or function was reduced in mothers of low-birthweight infants. This was a prospective cohort study in a general antenatal department of a university maternity hospital. Twenty-three mothers of small for gestational age (SGA) infants (birthweight mothers of appropriate for gestational age (AGA) infants (birthweight ≥ 10th centile) were recruited. Maternal EPC number and function, conventional cardiovascular risk markers, and cord blood adiponectin were measured. Median EPC count was lower (294 vs. 367, P = 0.005) and EPC migration was reduced (0.91 vs. 1.59, P < 0.001) in SGA compared with AGA infants, with no difference in EPC adhesion (0.221 vs. 0.284 fluorescence units, P = 0.257). Maternal triglyceride levels were higher in SGA than AGA infants (0.98 vs. 0.78 mmol/liter, P = 0.006), but there was no difference in cholesterol, glucose, insulin, glycosylated hemoglobin, adiponectin, or blood pressure. There was a moderate monotone (increasing) relationship between birthweight and umbilical cord blood adiponectin (r = 0.475, P = 0.005). Giving birth to an SGA infant was associated with lower maternal EPC number and reduced migratory function. Cord blood adiponectin was significantly correlated with birthweight.

Erythropoietin-enhanced endothelial progenitor cell recruitment in peripheral blood and renal vessels during experimental acute kidney injury in rats.

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Cakiroglu, Figen; Enders-Comberg, Sora Maria; Pagel, Horst; Rohwedel, Jürgen; Lehnert, Hendrik; Kramer, Jan

2016-03-01

Beneficial effects of erythropoietin (EPO) have been reported in acute kidney injury (AKI) when administered prior to induction of AKI. We studied the effects of EPO administration on renal function shortly after ischemic AKI. For this purpose, rats were subjected to renal ischemia for 30 min and EPO was administered at a concentration of 500 U/kg either i.v. as a single shot directly after ischemia or with an additional i.p. dose until 3 days after surgery. The results were compared with AKI rats without EPO application and a sham-operated group. Renal function was assessed by measurement of serum biochemical markers, histological grading, and using an isolated perfused kidney (IPK) model. Furthermore, we performed flow cytometry to analyze the concentration of endothelial progenitor cells (EPCs) in the peripheral blood and renal vessels. Following EPO application, there was only a statistically non-significant tendency of serum creatinine and urea to improve, particularly after daily EPO application. Renal vascular resistance and the renal perfusion rate were not significantly altered. In the histological analysis, acute tubular necrosis was only marginally ameliorated following EPO administration. In summary, we could not demonstrate a significant improvement in renal function when EPO was applied after AKI. Interestingly, however, EPO treatment resulted in a highly significant increase in CD133- and CD34-positive EPC both in the peripheral blood and renal vessels. © 2015 International Federation for Cell Biology.

Platelet released growth factors boost expansion of bone marrow derived CD34(+) and CD133(+) endothelial progenitor cells for autologous grafting.

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Lippross, Sebastian; Loibl, Markus; Hoppe, Sven; Meury, Thomas; Benneker, Lorin; Alini, Mauro; Verrier, Sophie

2011-01-01

Stem cell based autologous grafting has recently gained mayor interest in various surgical fields for the treatment of extensive tissue defects. CD34(+) and CD133(+) cells that can be isolated from the pool of bone marrow mononuclear cells (BMC) are capable of differentiating into mature endothelial cells in vivo. These endothelial progenitor cells (EPC) are believed to represent a major portion of the angiogenic regenerative cells that are released from bone marrow when tissue injury has occurred. In recent years tissue engineers increasingly looked at the process of vessel neoformation because of its major importance for successful cell grafting to replace damaged tissue. Up to now one of the greatest problems preventing a clinical application is the large scale of expansion that is required for such purpose. We established a method to effectively enhance the expansion of CD34(+) and CD133(+) cells by the use of platelet-released growth factors (PRGF) as a media supplement. PRGF were prepared from thrombocyte concentrates and used as a media supplement to iscove's modified dulbecco's media (IMDM). EPC were immunomagnetically separated from human bone morrow monocyte cells and cultured in IMDM + 10% fetal calf serum (FCS), IMDM + 5%, FCS + 5% PRGF and IMDM + 10% PRGF. We clearly demonstrate a statistically significant higher and faster cell proliferation rate at 7, 14, 21, and 28 days of culture when both PRGF and FCS were added to the medium as opposed to 10% FCS or 10% PRGF alone. The addition of 10% PRGF to IMDM in the absence of FCS leads to a growth arrest from day 14 on. In histochemical, immunocytochemical, and gene-expression analysis we showed that angiogenic and precursor markers of CD34(+) and CD133(+) cells are maintained during long-term culture. In summary, we established a protocol to boost the expansion of CD34(+) and CD133(+) cells. Thereby we provide a technical step towards the clinical application of autologous stem cell

Advanced glycation endproducts alter functions and promote apoptosis in endothelial progenitor cells through receptor for advanced glycation endproducts mediate overpression of cell oxidant stress.

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Chen, Jianfei; Song, Minbao; Yu, Shiyong; Gao, Pan; Yu, Yang; Wang, Hong; Huang, Lan

2010-02-01

Endothelial progenitor cells (EPCs) play an important role in preventing atherosclerosis. The factors that regulate the function of EPCs are not completely clear. Increased formation of advanced glycation endproducts (AGEs) is generally regarded as one of the main mechanisms responsible for vascular damage in patients with diabetes and atherosclerosis. AGEs lead to the generation of reactive oxygen species (ROS) and part of the regenerative capacity of EPCs seems to be due to their low baseline ROS levels and reduced sensitivity to ROS-induced cell apoptosis. Therefore, we tested the hypothesis that AGEs can alter functions and promote apoptosis in EPCs through overpress cell oxidant stress. EPCs, isolated from bone marrow, were cultured in the absence or presence of AGEs (50, 100, and 200 microg/ml). A modified Boyden's chamber was used to assess the migration of EPCs and the number of recultured EPCs was counted to measure the adhesiveness function. MTT assay was used to determine the proliferation function. ROS were analyzed using the ROS assay kit. A spectrophotometer was used to assess superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX) activity, and PCR was used to test mRNA expression of SOD and GSH-PX. SiRNA was used to block receptor for advanced glycation endproducts (RAGEs) expression. Apoptosis was evaluated by Annexin V immunostaining and TUNEL staining. Co-culturing with AGEs increases ROS production, decreases anti-oxidant defenses, overpresses oxidant stress, inhibits the proliferation, migration, and adhesion of EPCs, and induces EPCs apoptosis. In addition, these effects were attenuated during block RAGE protein expression by siRNA. AGEs may serve to impair EPCs functions through RAGE-mediate oxidant stress, and promote EPCs sensitivity toward oxidative-stress-mediated apoptosis, which indicates a new pathophysiological mechanism of disturbed vascular adaptation in atherosclerosis and suggests that lower levels of AGEs might improve the

Zoledronate inhibits ischemia-induced neovascularization by impairing the mobilization and function of endothelial progenitor cells.

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Shih-Hung Tsai

Full Text Available BACKGROUND: Bisphosphonates are a class of pharmacologic compounds that are commonly used to treat postmenopausal osteoporosis and malignant osteolytic processes. Studies have shown that bone marrow-derived endothelial progenitor cells (EPCs play a significant role in postnatal neovascularization. Whether the nitrogen-containing bisphosphonate zoledronate inhibits ischemia-induced neovascularization by modulating EPC functions remains unclear. METHODOLOGY/PRINCIPAL FINDINGS: Unilateral hindlimb ischemia was surgically induced in wild-type mice after 2 weeks of treatment with vehicle or zoledronate (low-dose: 30 μg/kg; high-dose: 100 μg/kg. Doppler perfusion imaging demonstrated that the ischemic limb/normal side blood perfusion ratio was significantly lower in wild-type mice treated with low-dose zoledronate and in mice treated with high-dose zoledronate than in controls 4 weeks after ischemic surgery (control vs. low-dose vs. high-dose: 87±7% vs. *61±18% vs. **49±17%, *p<0.01, **p<0.005 compared to control. Capillary densities were also significantly lower in mice treated with low-dose zoledronate and in mice treated with high-dose zoledronate than in control mice. Flow cytometry analysis showed impaired mobilization of EPC-like cells (Sca-1(+/Flk-1(+ after surgical induction of ischemia in mice treated with zoledronate but normal levels of mobilization in mice treated with vehicle. In addition, ischemic tissue from mice that received zoledronate treatment exhibited significantly lower levels of the active form of MMP-9, lower levels of VEGF, and lower levels of phosphorylated eNOS and phosphorylated Akt than ischemic tissue from mice that received vehicle. Results of the in vitro studies showed that incubation with zoledronate inhibited the viability, migration, and tube-forming capacities of EPC. CONCLUSIONS/SIGNIFICANCE: Zoledronate inhibited ischemia-induced neovascularization by impairing EPC mobilization and angiogenic functions

Endothelial cell-derived microparticles induce plasmacytoid dendritic cell maturation: potential implications in inflammatory diseases.

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Angelot, Fanny; Seillès, Estelle; Biichlé, Sabeha; Berda, Yael; Gaugler, Béatrice; Plumas, Joel; Chaperot, Laurence; Dignat-George, Françoise; Tiberghien, Pierre; Saas, Philippe; Garnache-Ottou, Francine

2009-11-01

Increased circulating endothelial microparticles, resulting from vascular endothelium dysfunction, and plasmacytoid dendritic cell activation are both encountered in common inflammatory disorders. The aim of our study was to determine whether interactions between endothelial microparticles and plasmacytoid dendritic cells could contribute to such pathologies. Microparticles generated from endothelial cell lines, platelets or activated T cells were incubated with human plasmacytoid dendritic cells sorted from healthy donor blood or with monocyte-derived dendritic cells. Dendritic cell maturation was evaluated by flow cytometry, cytokine secretion as well as naive T-cell activation and polarization. Labeled microparticles were also used to study cellular interactions. Endothelial microparticles induced plasmacytoid dendritic cell maturation. In contrast, conventional dendritic cells were resistant to endothelial microparticle-induced maturation. In addition to upregulation of co-stimulatory molecules, endothelial microparticle-matured plasmacytoid dendritic cells secreted inflammatory cytokines (interleukins 6 and 8, but no interferon-alpha) and also induced allogeneic naive CD4(+) T cells to proliferate and to produce type 1 cytokines such as interferon-gamma and tumor necrosis factor-alpha. Endothelial microparticle endocytosis by plasmacytoid dendritic cells appeared to be required for plasmacytoid dendritic cell maturation. Importantly, the ability of endothelial microparticles to induce plasmacytoid dendritic cells to mature was specific as microparticles derived from activated T cells or platelets (the major source of circulating microparticules in healthy subjects) did not induce such plasmacytoid dendritic cell maturation. Our data show that endothelial microparticles specifically induce plasmacytoid dendritic cell maturation and production of inflammatory cytokines. This novel activation pathway may be implicated in various inflammatory disorders and

Circulating hematopoietic progenitors and CD34(+) cells predicted successful hematopoietic stem cell harvest in myeloma and lymphoma patients: experiences from a single institution.

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Yu, Jui-Ting; Cheng, Shao-Bin; Yang, Youngsen; Chang, Kuang-Hsi; Hwang, Wen-Li; Teng, Chieh-Lin Jerry

2016-01-01

Previous studies have shown that the numbers of both circulating hematopoietic progenitor cell (HPC) and CD34(+) cell are positively correlated with CD34(+) cell harvest yield. However, the minimal numbers of both circulating HPCs and CD34(+) cells required for performing an efficient hematopoietic stem cell (HSC) harvest in lymphoma and myeloma patients have not been defined in our institution. Medical records of 50 lymphoma and myeloma patients undergoing peripheral blood HSC harvest in our institution were retrospectively reviewed. The minimal and optimal HSC harvest yield required for the treatment was considered to be ≥2×10(6) CD34(+) cells/kg and ≥5×10(6) CD34(+) cells/kg, respectively. The minimally required or optimal HSC yield obtained was not influenced by age (≥60 years), sex, underlying malignancies, disease status, multiple rounds of chemotherapy, or history of radiotherapy. The numbers of both circulating HPC and CD34(+) cell were higher in patients with minimally required HSC yields (P=0.000 for HPC and P=0.000 for CD34(+) cell) and also in patients with optimal HSC yields (P=0.011 for HPC and P=0.006 for CD34(+) cell). The cell count cutoff for obtaining minimally required HSC harvest was determined to be 20/mm(3) for HPCs and 10/mm(3) for CD34(+) cells. Furthermore, the cell count cutoff for obtaining optimal HSC harvest was determined to be 60/mm(3) for HPCs and 35/mm(3) for CD34(+) cells. A total of 60/mm(3) of HPCs and 35/mm(3) of CD34(+) cells in peripheral blood predicted optimal HSC harvest in lymphoma and myeloma patients.

A continuum mathematical model of endothelial layer maintenance and senescence.

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Wang, Ying; Aguda, Baltazar D; Friedman, Avner

2007-08-10

The monolayer of endothelial cells (ECs) lining the inner wall of blood vessels deteriorates as a person ages due to a complex interplay of a variety of causes including cell death arising from shear stress of blood flow and cellular oxidative stress, cellular senescence, and decreased rate of replacement of dead ECs by progenitor stem cells. A continuum mathematical model is developed to describe the dynamics of large EC populations of the endothelium using a system of differential equations for the number densities of cells of different generations starting from endothelial progenitors to senescent cells, as well as the densities of dead cells and the holes created upon clearing dead cells. Aging of cells is manifested in three ways, namely, losing the ability to divide when the Hayflick limit of 50 generations is reached, decreasing replication rate parameters and increasing death rate parameters as cells divide; due to the dependence of these rate parameters on cell generation, the model predicts a narrow distribution of cell densities peaking at a particular cell generation. As the chronological age of a person advances, the peak of the distribution - corresponding to the age of the endothelium - moves towards senescence correspondingly. However, computer simulations also demonstrate that sustained and enhanced stem cell homing can halt the aging process of the endothelium by maintaining a stationary cell density distribution that peaks well before the Hayflick limit. The healing rates of damaged endothelia for young, middle-aged, and old persons are compared and are found to be particularly sensitive to the stem cell homing parameter. The proposed model describes the aging of the endothelium as being driven by cellular senescence, with a rate that does not necessarily correspond to the chronological aging of a person. It is shown that the age of the endothelium depends sensitively on the homing rates of EC progenitor cells.

Endothelial cells and hematopoiesis: a light microscopic study of fetal, normal, and pathologic human bone marrow in plastic-embedded sections.

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Islam, A; Glomski, C; Henderson, E S

1992-07-01

The origin and morphological identity of hematopoietic progenitor cells, as well as their precursor, the pleuripotential hematopoietic stem cell (HSC), has not been established. Our studies of 2 microns sectioned undecalcified plastic-embedded bone marrow (BM) from healthy human fetuses; normal adults; patients with acute myeloblastic leukemia (AML), acute lymphoblastic leukemia (ALL), and chronic granulocytic leukemia (CGL) in various stages (chronic, accelerated, acute blastic phase, and after autografting); and patients recovering from therapy-induced marrow hypoplasia suggest that proliferative hematopoietic zones exist near the endosteum (endosteal marrow) and the vascular endothelium (capillary and sinus-lining endothelium) and a maturational zone distal to these regions. In some of these areas, morphologically recognizable hematopoietic cells were seen and interpreted as emerging and maturing in a sequential progression, suggesting an origin from the endosteal or endothelial progenitors. In other loci, early hematopoietic cells were seen in close contact with the endosteal or vascular endothelial (VE) cells. This latter relationship suggested that these areas of cellular contact were important and represented sites of cell to cell interaction that may be associated with the liberation of growth factors by endosteal and endothelial cells and their action on hematopoietic progenitor cells. Following treatment-induced hypoplasia, the endosteal and VE cells were seen to modulate, transform, and migrate into the surrounding empty and edematous marrow space as fibroblasts. Later, as hemopoietic regeneration began, clusters of regenerating hematopoietic cells were seen adjacent to bone trabecule (BT) and near the vascular endothelium. We postulate that endosteal and VE cells are the equivalent of embryonal-stage, undifferentiated mesenchyme and, under the appropriate regulatory influence, are capable of modulation and transformation (differentiation) into stromal

Autologous circulating angiogenic cells treated with osteopontin and delivered via a collagen scaffold enhance wound healing in the alloxan-induced diabetic rabbit ear ulcer model.

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O'Loughlin, Aonghus; Kulkarni, Mangesh; Vaughan, Erin E; Creane, Michael; Liew, Aaron; Dockery, Peter; Pandit, Abhay; O'Brien, Timothy

2013-01-01

Diabetic foot ulceration is the leading cause of amputation in people with diabetes mellitus. Peripheral vascular disease is present in the majority of patients with diabetic foot ulcers. Despite standard treatments there exists a high amputation rate. Circulating angiogenic cells previously known as early endothelial progenitor cells are derived from peripheral blood and support angiogenesis and vasculogenesis, providing a potential topical treatment for non-healing diabetic foot ulcers. A scaffold fabricated from Type 1 collagen facilitates topical cell delivery to a diabetic wound. Osteopontin is a matricellular protein involved in wound healing and increases the angiogenic potential of circulating angiogenic cells. A collagen scaffold seeded with circulating angiogenic cells was developed. Subsequently the effect of autologous circulating angiogenic cells that were seeded in a collagen scaffold and topically delivered to a hyperglycemic cutaneous wound was assessed. The alloxan-induced diabetic rabbit ear ulcer model was used to determine healing in response to the following treatments: collagen seeded with autologous circulating angiogenic cells exposed to osteopontin, collagen seeded with autologous circulating angiogenic cells, collagen alone and untreated wound. Stereology was used to assess angiogenesis in wounds. The cells exposed to osteopontin and seeded on collagen increased percentage wound closure as compared to other groups. Increased angiogenesis was observed with the treatment of collagen and collagen seeded with circulating angiogenic cells. These results demonstrate that topical treatment of full thickness cutaneous ulcers with autologous circulating angiogenic cells increases wound healing. Cells exposed to the matricellular protein osteopontin result in superior wound healing. The wound healing benefit is associated with a more efficient vascular network. This topical therapy provides a potential novel therapy for the treatment of non

Mel-18, a mammalian Polycomb gene, regulates angiogenic gene expression of endothelial cells.

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Jung, Ji-Hye; Choi, Hyun-Jung; Maeng, Yong-Sun; Choi, Jung-Yeon; Kim, Minhyung; Kwon, Ja-Young; Park, Yong-Won; Kim, Young-Myeong; Hwang, Daehee; Kwon, Young-Guen

2010-10-01

Mel-18 is a mammalian homolog of Polycomb group (PcG) genes. Microarray analysis revealed that Mel-18 expression was induced during endothelial progenitor cell (EPC) differentiation and correlates with the expression of EC-specific protein markers. Overexpression of Mel-18 promoted EPC differentiation and angiogenic activity of ECs. Accordingly, silencing Mel-18 inhibited EC migration and tube formation in vitro. Gene expression profiling showed that Mel-18 regulates angiogenic genes including kinase insert domain receptor (KDR), claudin 5, and angiopoietin-like 2. Our findings demonstrate, for the first time, that Mel-18 plays a significant role in the angiogenic function of ECs by regulating endothelial gene expression. Copyright © 2010 Elsevier Inc. All rights reserved.

Vascular niche promotes hematopoietic multipotent progenitor formation from pluripotent stem cells

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Gori, Jennifer L.; Butler, Jason M.; Chan, Yan-Yi; Chandrasekaran, Devikha; Poulos, Michael G.; Ginsberg, Michael; Nolan, Daniel J.; Elemento, Olivier; Wood, Brent L.; Adair, Jennifer E.; Rafii, Shahin; Kiem, Hans-Peter

2015-01-01

Pluripotent stem cells (PSCs) represent an alternative hematopoietic stem cell (HSC) source for treating hematopoietic disease. The limited engraftment of human PSC–derived (hPSC-derived) multipotent progenitor cells (MPP) has hampered the clinical application of these cells and suggests that MPP require additional cues for definitive hematopoiesis. We hypothesized that the presence of a vascular niche that produces Notch ligands jagged-1 (JAG1) and delta-like ligand-4 (DLL4) drives definitive hematopoiesis. We differentiated hes2 human embryonic stem cells (hESC) and Macaca nemestrina–induced PSC (iPSC) line-7 with cytokines in the presence or absence of endothelial cells (ECs) that express JAG1 and DLL4. Cells cocultured with ECs generated substantially more CD34+CD45+ hematopoietic progenitors compared with cells cocultured without ECs or with ECs lacking JAG1 or DLL4. EC-induced cells exhibited Notch activation and expressed HSC-specific Notch targets RUNX1 and GATA2. EC-induced PSC-MPP engrafted at a markedly higher level in NOD/SCID/IL-2 receptor γ chain–null (NSG) mice compared with cytokine-induced cells, and low-dose chemotherapy-based selection further increased engraftment. Long-term engraftment and the myeloid-to-lymphoid ratio achieved with vascular niche induction were similar to levels achieved for cord blood–derived MPP and up to 20-fold higher than those achieved with hPSC-derived MPP engraftment. Our findings indicate that endothelial Notch ligands promote PSC-definitive hematopoiesis and production of long-term engrafting CD34+ cells, suggesting these ligands are critical for HSC emergence. PMID:25664855

Triazole RGD antagonist reverts TGFβ1-induced endothelial-to-mesenchymal transition in endothelial precursor cells.

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Bianchini, Francesca; Peppicelli, Silvia; Fabbrizzi, Pierangelo; Biagioni, Alessio; Mazzanti, Benedetta; Menchi, Gloria; Calorini, Lido; Pupi, Alberto; Trabocchi, Andrea

2017-01-01

Fibrosis is the dramatic consequence of a dysregulated reparative process in which activated fibroblasts (myofibroblasts) and Transforming Growth Factor β1 (TGFβ1) play a central role. When exposed to TGFβ1, fibroblast and epithelial cells differentiate in myofibroblasts; in addition, endothelial cells may undergo endothelial-to-mesenchymal transition (EndoMT) and actively participate to the progression of fibrosis. Recently, the role of αv integrins, which recognize the Arg-Gly-Asp (RGD) tripeptide, in the release and signal transduction activation of TGFβ1 became evident. In this study, we present a class of triazole-derived RGD antagonists that interact with αvβ3 integrin. Above different compounds, the RGD-2 specifically interferes with integrin-dependent TGFβ1 EndoMT in Endothelial Colony-Forming Cells (ECPCs) derived from circulating Endothelial Precursor Cells (ECPCs). The RGD-2 decreases the amount of membrane-associated TGFβ1, and reduces both ALK5/TGFβ1 type I receptor expression and Smad2 phosphorylation in ECPCs. We found that RGD-2 antagonist reverts EndoMT, reducing α-smooth muscle actin (α-SMA) and vimentin expression in differentiated ECPCs. Our results outline the critical role of integrin in fibrosis progression and account for the opportunity of using integrins as target for anti-fibrotic therapeutic treatment.

Analysis of Circulating Vascular Endothelial Growth Factor and Its Soluble Receptors in Patients with Different Forms of Chronic Urticaria

Directory of Open Access Journals (Sweden)

Julia Jagodzinska

2015-01-01

Full Text Available Background. Vascular endothelial growth factor (VEGF is a powerful enhancer of vascular permeability and inflammatory response; however its significance in chronic urticaria is poorly recognised. Aim. To compare free circulating levels of VEGF and its soluble receptors (sVEGFR1 and VEGFR2 in patients with different forms of chronic urticaria. Methods. The concentrations of VEGF and its receptors in plateletpoor plasma (PPP/plasma were measured using enzyme-linked immunosorbent assay in chronic urticaria: (1 chronic spontaneous urticaria (CSU with positive autologous serum skin test (ASST, (2 CSU with negative response to ASST, (3 CSU with concomitant euthyroid Hashimoto’s thyroiditis (CSU/Hashimoto, (4 delayed pressure urticaria (DPU, and the healthy subjects. Results. There were no significant differences in VEGF concentration in PPP between CSU groups and the healthy subjects. Contrary, VEGF concentration was significantly higher in DPU and CSU/Hashimoto patients as compared with the healthy subjects and CSU groups. Furthermore, VEGF value in CSU/Hashimoto patients during the remission was similar to that of the active period and significantly higher than the healthy subjects; VEGF concentration was significantly correlated with TSH. Plasma concentrations of sVEGF1 and sVEGF2 were similar in chronic urticaria patients and the healthy subjects. Conclusions. Increased free circulating VEGF concentration may result from the urticarial process itself as well as concomitant Hashimoto’s thyroiditis.

Direct evidence that the VEGF-specific antibody bevacizumab has antivascular effects in human rectal cancer

Science.gov (United States)

Willett, Christopher G; Boucher, Yves; di Tomaso, Emmanuelle; Duda, Dan G; Munn, Lance L; Tong, Ricky T; Chung, Daniel C; Sahani, Dushyant V; Kalva, Sanjeeva P; Kozin, Sergey V; Mino, Mari; Cohen, Kenneth S; Scadden, David T; Hartford, Alan C; Fischman, Alan J; Clark, Jeffrey W; Ryan, David P; Zhu, Andrew X; Blaszkowsky, Lawrence S; Chen, Helen X; Shellito, Paul C; Lauwers, Gregory Y; Jain, Rakesh K

2009-01-01

The effects of vascular endothelial growth factor (VEGF) blockade on the vascular biology of human tumors are not known. Here we show here that a single infusion of the VEGF-specific antibody bevacizumab decreases tumor perfusion, vascular volume, microvascular density, interstitial fluid pressure and the number of viable, circulating endothelial and progenitor cells, and increases the fraction of vessels with pericyte coverage in rectal carcinoma patients. These data indicate that VEGF blockade has a direct and rapid antivascular effect in human tumors. PMID:14745444

Detection and Quantification of Vascular Endothelial Growth Factor Receptor Tyrosine Kinases in Primary Human Endothelial Cells.

Science.gov (United States)

Fearnley, Gareth W; Wheatcroft, Stephen B; Ponnambalam, Sreenivasan

2015-01-01

Proteins differ widely in their pattern of expression depending on organism, tissue, and regulation in response to changing conditions. In the mammalian vasculature, the endothelium responds to vascular endothelial growth factors (VEGFs) via membrane-bound receptor tyrosine kinases (VEGFRs) to modulate many aspects of vascular physiology including vasculogenesis, angiogenesis, and blood pressure. Studies on VEGFR biology are thus dependent on detecting expression levels in different cell types and evaluating how changes in protein levels correlate with changing conditions including circulating VEGF levels. Here, we present a robust immunoblot-based protocol for detecting and quantifying VEGFRs in human endothelial cells. Using internal and external standards, we can rapidly evaluate receptor copy number and assess how this is altered in response to the cellular environment.

Relationship between spontaneous γH2AX foci formation and progenitor functions in circulating hematopoietic stem and progenitor cells among atomic-bomb survivors.

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Kajimura, Junko; Kyoizumi, Seishi; Kubo, Yoshiko; Misumi, Munechika; Yoshida, Kengo; Hayashi, Tomonori; Imai, Kazue; Ohishi, Waka; Nakachi, Kei; Weng, Nan-Ping; Young, Lauren F; Shieh, Jae-Hung; Moore, Malcolm A; van den Brink, Marcel R M; Kusunoki, Yoichiro

2016-05-01

Accumulated DNA damage in hematopoietic stem cells is a primary mechanism of aging-associated dysfunction in human hematopoiesis. About 70 years ago, atomic-bomb (A-bomb) radiation induced DNA damage and functional decreases in the hematopoietic system of A-bomb survivors in a radiation dose-dependent manner. The peripheral blood cell populations then recovered to a normal range, but accompanying cells derived from hematopoietic stem cells still remain that bear molecular changes possibly caused by past radiation exposure and aging. In the present study, we evaluated radiation-related changes in the frequency of phosphorylated (Ser-139) H2AX (γH2AX) foci formation in circulating CD34-positive/lineage marker-negative (CD34+Lin-) hematopoietic stem and progenitor cells (HSPCs) among 226Hiroshima A-bomb survivors. An association between the frequency of γH2AX foci formation in HSPCs and the radiation dose was observed, but the γH2AX foci frequency was not significantly elevated by past radiation. We found a negative correlation between the frequency of γH2AX foci formation and the length of granulocyte telomeres. A negative interaction effect between the radiation dose and the frequency of γH2AX foci was suggested in a proportion of a subset of HSPCs as assessed by the cobblestone area-forming cell assay (CAFC), indicating that the self-renewability of HSPCs may decrease in survivors who were exposed to a higher radiation dose and who had more DNA damage in their HSPCs. Thus, although many years after radiation exposure and with advancing age, the effect of DNA damage on the self-renewability of HSPCs may be modified by A-bomb radiation exposure. Copyright © 2016 Elsevier B.V. All rights reserved.

CURRENT METHODS OF ENDOTHELIAL DYSFUNCTION ASSESSMENT AND THEIR POSSIBLE USE IN THE PRACTICAL MEDICINE

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A. V. Shabrov

2016-01-01

Full Text Available A review contains a description of the most common methods of evaluation and monitoring of "endothelial dysfunction" that are assessed in terms of their information content and applicability in the practice of medicine. The term "endothelial function" is interpreted primarily as a function of the regulation of capillary blood flow, carried out by the expense of the dynamic change of the phase of vasoconstriction and vasodilatation in vessels of resistive type (in accordance with the changing needs of cellular metabolism. Assessment of endothelial dysfunction is understood as a generalized indicator of the extent and nature of violations of the regulation of peripheral circulation. It includes an assessment of imbalances between endotheliumdependent vasoconstrictor and vasodilating factors or mismatch of the local and central regulation of capillary blood flow in response to various functional tests or other effects (eg, cold test, or test with local ischemia. All methods of endothelial dysfunction assessment in the survey are divided into invasive and non-invasive. The main feature of invasive methods lies in the direct effect on the endothelium of the coronary or other vessels by introducing into these vessels vasoactive substances such as acetylcholine. Response to the test (vasoconstriction or vasodilation is evaluated by coronary angiography or by ultrasound. Non-invasive methods of the assessment of endothelial dysfunction or functions of regulation of the peripheral circulation are regarded as the most promising for widespread use. There are two basic methods that underlie functional tests: methods PAT (peripheral arterial tone and PHG (polyhepatography. Assessment of endothelial dysfunction in many modern scientific researches is important. They are regarded as the causative factors of many different diseases. Such assessments can be useful in everyday medical practice. Assessment of endothelial function provides the clinician with

Angiocrine functions of organ-specific endothelial cells

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Rafii, Shahin; Butler, Jason M; Ding, Bi-Sen

2016-01-01

Preface Endothelial cells lining blood vessel capillaries are not just passive conduits for delivering blood. Tissue-specific endothelium establish specialized vascular niches that deploy specific sets of growth factors, known as angiocrine factors, which actively participate in inducing, specifying, patterning, and guiding organ regeneration and maintaining homeostasis and metabolism. Angiocrine factors upregulated in response to injury orchestrates self-renewal and differentiation of tissue-specific repopulating resident stem and progenitor cells into functional organs. Uncovering the precise mechanisms whereby physiological-levels of angiocrine factors are spatially and temporally produced, and distributed by organotypic endothelium to repopulating cells, will lay the foundation for driving organ repair without scarring. PMID:26791722

Ca2+ signalling in endothelial progenitor cells: a novel means to improve cell-based therapy and impair tumour vascularisation.

Science.gov (United States)

Moccia, Francesco; Lodola, Francesco; Dragoni, Silvia; Bonetti, Elisa; Bottino, Cinzia; Guerra, Germano; Laforenza, Umberto; Rosti, Vittorio; Tanzi, Franco

2014-01-01

Endothelial progenitor cells (EPCs) have recently been employed in cell-based therapy (CBT) to promote regeneration of ischemic organs, such as heart and limbs. Furthermore, EPCs may sustain tumour vascularisation and provide an additional target for anticancer therapies. CBT is limited by the paucity of cells harvested from peripheral blood and suffers from several pitfalls, including the low rate of engrafted EPCs, whereas classic antiangiogenic treatments manifest a number of side effects and may induce resistance into the patients. CBT will benefit of a better understanding of the signal transduction pathway(s) which drive(s) EPC proliferation, trafficking, and incorporation into injured tissues. At the same time, this information might outline alternative molecular targets to impair tumor neovascularisation and improve the therapeutic outcome of antiangiogenic strategies. An increase in intracellular Ca(2+) concentration is the key signal in the regulation of cellular replication, migration, and differentiation. In particular, Ca(2+) signalling may regulate cellcycle progression, due to the Ca(2+)-sensitivity of a number of cycline-dependent kinases, and gene expression, owing to the Ca(2+)-dependence of several transcription factors. Recent work has outlined the role of the so-called store-operated Ca(2+) entry in driving EPC proliferation and migration. Unravelling the mechanisms guiding EPC engraftment into neovessels might supply the biological bases required to improve CBT and anticancer treatments. For example, genetic manipulation of the Ca(2+) signalling machinery could provide a novel approach to increase the extent of limb regeneration or preventing tumour vascularisation by EPCs.

Angiocrine factors from Akt-activated endothelial cells balance self-renewal and differentiation of haematopoietic stem cells

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Kobayashi, Hideki; Butler, Jason M.; O'Donnell, Rebekah; Kobayashi, Mariko; Ding, Bi-Sen; Bonner, Bryant; Chiu, Vi K.; Nolan, Daniel J.; Shido, Koji; Benjamin, Laura; Rafii, Shahin

2010-01-01

Endothelial cells establish an instructive vascular niche that reconstitutes haematopoietic stem and progenitor cells (HSPCs) through release of specific paracrine growth factors, known as angiocrine factors. However, the mechanism by which endothelial cells balance the rate of proliferation and lineage-specific differentiation of HSPCs is unknown. Here, we demonstrate that Akt activation in endothelial cells, through recruitment of mTOR, but not the FoxO pathway, upregulates specific angiocrine factors that support expansion of CD34−Flt3− KLS HSPCs with long-term haematopoietic stem cell (LT-HSC) repopulation capacity. Conversely, co-activation of Akt-stimulated endothelial cells with p42/44 MAPK shifts the balance towards maintenance and differentiation of the HSPCs. Selective activation of Akt1 in the endothelial cells of adult mice increased the number of colony forming units in the spleen and CD34−Flt3− KLS HSPCs with LT-HSC activity in the bone marrow, accelerating haematopoietic recovery. Therefore, the activation state of endothelial cells modulates reconstitution of HSPCs through the upregulation of angiocrine factors, with Akt–mTOR-activated endothelial cells supporting the self-renewal of LT-HSCs and expansion of HSPCs, whereas MAPK co-activation favours maintenance and lineage-specific differentiation of HSPCs. PMID:20972423

Epidermal growth factor-like domain 7 is a marker of the endothelial lineage and active angiogenesis.

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Bambino, Kathryn; Lacko, Lauretta A; Hajjar, Katherine A; Stuhlmann, Heidi

2014-07-01

Epidermal growth factor-like domain 7 (Egfl7) expression in the developing embryo is largely restricted to sites of mesodermal progenitors of angioblasts/hemangioblasts and the vascular endothelium. We hypothesize that Egfl7 marks the endothelial lineage during embryonic development, and can be used to define the emergence of endothelial progenitor cells, as well as to visualize newly-forming vasculature in the embryo and during the processes of physiologic and pathologic angiogenesis in the adult. We have generated a transgenic mouse strain that expresses enhanced green fluorescent protein (eGFP) under the control of a minimal Egfl7 regulatory sequence (Egfl7:eGFP). Expression of the transgene recapitulated that of endogenous Egfl7 at sites of vasculogenesis and angiogenesis in the allantois, yolk sac, and in the embryo proper. The transgene was not expressed in the quiescent endothelium of most adult organs. However, the uterus and ovary, which undergo vascular growth and remodeling throughout the estrus cycle, expressed high levels of Egfl7:eGFP. Importantly, expression of the Egfl7:eGFP transgene was induced in adult neovasculature. We also found that increased Egfl7 expression contributed to pathologic revascularization in the mouse retina. To our knowledge, this is the first mouse model that enables monitoring of endothelial cells at sites of active vasculogenesis and angiogenesis. This model also facilitated the isolation and characterization of EGFL7(+) endothelial cell populations by fluorescence activated cell sorting (FACS). Together, our results demonstrate that the Egfl7:eGFP reporter mouse is a valuable tool that can be used to elucidate the mechanisms by which blood vessels form during development and under pathologic circumstances. © 2014 Wiley Periodicals, Inc.

Late effects of radiation on the central nervous system: role of vascular endothelial damage and glial stem cell survival.

NARCIS (Netherlands)

Coderre, J.A.; Morris, G.M.; Micca, P.L.; Hopewell, J.W.; Verhagen, I.; Kleiboer, B.J.; Kogel, A.J. van der

2006-01-01

Selective irradiation of the vasculature of the rat spinal cord was used in this study, which was designed specifically to address the question as to whether it is the endothelial cell or the glial progenitor cell that is the target responsible for late white matter necrosis in the CNS. Selective

Alterations in triglyceride rich lipoproteins are related to endothelial dysfunction in metabolic syndrome.

Science.gov (United States)

Lucero, Diego; López, Graciela I; Gorzalczany, Susana; Duarte, Mariano; González Ballerga, Esteban; Sordá, Juan; Schreier, Laura; Zago, Valeria

2016-08-01

Our aim was to analyze the effect of circulating triglyceride rich lipoprotein (TRL) on endothelial function in metabolic syndrome (MetS). We studied 40 patients with MetS (ATPIII), divided into those presenting normal endothelial function (n=19) and those with endothelial dysfunction (n=21) by means of the evaluation of pulse wave velocity, before and after brachial artery ischemia. In fasting serum we measured lipid and lipoprotein profile, insulin and glucose (HOMA-IR). Moreover, isolated TRL (d<1006g/l) were chemically characterized. In parallel, using randomly selected TRL from MetS patients with endothelial dysfunction (n=6) and MetS patients with normal endothelial function (n=6), the ability of TRL to inhibit ACh-induced vasorelaxation (10(-9)-10(-5)mM) on aortic rings previously pre-contracted by noradrenaline (10(-8)mM) was evaluated. Interestingly, TRL isolated from MetS patients presenting endothelial dysfunction showed triglyceride over-enrichment (59.1±4.8 vs. 54.1±4.7%; p=0.04), even after adjusting by potential confounders (p=0.05). In addition, while TRL resulting from both MetS groups significantly inhibited endothelium dependent vasorelaxation (p<0.001), TRL from MetS patients with endothelial dysfunction showed a strong tendency to a greater inhibition of vasorelaxation (p=0.06). Moreover, TRL-triglyceride (%) showed a strong tendency to correlate with the grade of vasorelaxation inhibition exerted by TRL (r=0.60; p=0.05). These results, taken together, would allow inferring for the first time that the predominance of triglyceride over-enriched TRL in circulation in MetS would induce endothelial dysfunction, contributing to the inherent cardiovascular risk of MetS. Copyright © 2016 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Comparison of three fluorescence labeling and tracking methods of endothelial progenitor cells in laser-injured retina

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Hui Shi

2018-04-01

Full Text Available AIM: To compare three kinds of fluorescent probes for in vitro labeling and in vivo tracking of endothelial progenitor cells (EPCs in a mouse model of laser-induced retinal injury. METHODS: EPCs were isolated from human umbilical cord blood mononuclear cells and labeled with three different fluorescent probes: 5-(and-6-carboxyfluorescein diacetate succinimidyl ester (CFSE, 1,1′-dilinoleyl-3,3,3′,3′-tetramethylindo-carbocyanine perchlorate linked acetylated low-density lipoprotein (DiI-AcLDL, and green fluorescent protein (GFP. The fluorescent intensity of EPCs was examined by confocal microscopy. Survival rate of labeled EPCs was calculated with trypan blue staining, and their adhesive capability was assessed. A mouse model of retinal injury was induced by laser, and EPCs were injected into the vitreous cavity. Frozen section and fluorescein angiography on flat-mounted retinal samples was employed to track the labeled EPCs in vivo. RESULTS: EPCs labeled with CFSE and DiI-AcLDL exhibited an intense green and red fluorescence at the beginning; the fluorescence intensity decreased gradually to 20.23% and 49.99% respectively, after 28d. On the contrary, the florescent intensity of GFP-labeled EPCs increased in a time-dependent manner. All labeled EPCs showed normal morphology and no significant change in survival and adhesive capability. In the mouse model, transplantation of EPCs showed a protective effect against retinal injury. EPCs labeled with CFSE and DiI-AcLDL were successfully tracked in mice during the development of retinal injury and repair; however, GFP-labeled EPCs were not detected in the laser-injured mouse retina. CONCLUSION: The three fluorescent markers used in this study have their own set of advantages and disadvantages. CFSE and DiI-AcLDL are suitable for short-term EPC-labeling, while GFP should be used for long-term labeling. The choice of fluorescent markers should be guided by the purpose of the study.

Reciprocal interactions between endothelial cells and macrophages in angiogenic vascular niches

Energy Technology Data Exchange (ETDEWEB)

Baer, Caroline; Squadrito, Mario Leonardo [The Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), 1015 Lausanne (Switzerland); Iruela-Arispe, M. Luisa, E-mail: arispe@mcdb.ucla.edu [The Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), 1015 Lausanne (Switzerland); Department of Molecular, Cell and Developmental Biology and Molecular Biology Institute, University of California, Los Angeles 90095, CA (United States); De Palma, Michele, E-mail: michele.depalma@epfl.ch [The Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), 1015 Lausanne (Switzerland)

2013-07-01

The ability of macrophages to promote vascular growth has been associated with the secretion and local delivery of classic proangiogenic factors (e.g., VEGF-A and proteases). More recently, a series of studies have also revealed that physical contact of macrophages with growing blood vessels coordinates vascular fusion of emerging sprouts. Interestingly, the interactions between macrophages and vascular endothelial cells (ECs) appear to be bidirectional, such that activated ECs also support the expansion and differentiation of proangiogenic macrophages from myeloid progenitors. Here, we discuss recent findings suggesting that dynamic angiogenic vascular niches might also exist in vivo, e.g. in tumors, where sprouting blood vessels and immature myeloid cells like monocytes engage in heterotypic interactions that are required for angiogenesis. Finally, we provide an account of emerging mechanisms of cell-to-cell communication that rely on secreted microvesicles, such as exosomes, which can offer a vehicle for the rapid exchange of molecules and genetic information between macrophages and ECs engaged in angiogenesis. -- Highlights: • Macrophages promote angiogenesis by secreting proangiogenic factors. • Macrophages modulate angiogenesis via cell-to-cell contacts with endothelial cells. • Endothelial cells promote the differentiation of proangiogenic macrophages. • Macrophages and endothelial cells may cooperate to form angiogenic vascular niches.

Reciprocal interactions between endothelial cells and macrophages in angiogenic vascular niches

International Nuclear Information System (INIS)

Baer, Caroline; Squadrito, Mario Leonardo; Iruela-Arispe, M. Luisa; De Palma, Michele

2013-01-01

The ability of macrophages to promote vascular growth has been associated with the secretion and local delivery of classic proangiogenic factors (e.g., VEGF-A and proteases). More recently, a series of studies have also revealed that physical contact of macrophages with growing blood vessels coordinates vascular fusion of emerging sprouts. Interestingly, the interactions between macrophages and vascular endothelial cells (ECs) appear to be bidirectional, such that activated ECs also support the expansion and differentiation of proangiogenic macrophages from myeloid progenitors. Here, we discuss recent findings suggesting that dynamic angiogenic vascular niches might also exist in vivo, e.g. in tumors, where sprouting blood vessels and immature myeloid cells like monocytes engage in heterotypic interactions that are required for angiogenesis. Finally, we provide an account of emerging mechanisms of cell-to-cell communication that rely on secreted microvesicles, such as exosomes, which can offer a vehicle for the rapid exchange of molecules and genetic information between macrophages and ECs engaged in angiogenesis. -- Highlights: • Macrophages promote angiogenesis by secreting proangiogenic factors. • Macrophages modulate angiogenesis via cell-to-cell contacts with endothelial cells. • Endothelial cells promote the differentiation of proangiogenic macrophages. • Macrophages and endothelial cells may cooperate to form angiogenic vascular niches

[VEGF165 transfected endothelial progenitor cells mediated by lentivirus alleviated ALI in rats].

Science.gov (United States)

He, Zhaohui; He, Huiwei; Lu, Yuanhua; Chen, Zhi; Xu, Fanghua; Wang, Rongsheng; Yang, Chunli

2017-11-01

To investigate the protective effects of vascular endothelial growth factor-165 (VEGF165) transfected the endothelial progenitor cells (EPCs) mediated by lentivirus on acute lung injury (ALI) in rats. The mononuclear cells from the male Sprague-Dawley (SD) rats were isolated and cultured to get the EPCs for study. The lentivirus vector carrying the human VEGF165 gene was constructed. According to the random number table method, 90 male SD rats were divided into ALI model group, phosphate buffer solution (PBS) group, EPCs treatment group, none transfected EPCs treatment group and VEGF165 transfected EPCs treatment group, and the rats in each group were subdivided into 4, 12 and 48 hours subgroups, with 6 rats in each subgroup. The rat model of ALI was reproduced by intravenous injection of oleic acid (0.15 μL/g). Then each treatment group was given PBS, EPCs, none transfected EPCs and VEGF165 transfected EPCs respectively with the same volume of 0.2 mL. For the groups with cells, about 1×10 6 cells were contained. Abdominal aortic blood and lung tissue were harvested at 4, 12 and 48 hours. Arterial blood gas analysis was performed. The lung wet/dry weight ratio (W/D) was calculated. The expressions of induced nitric oxide synthase (iNOS), endothelin-1 (ET-1) and VEGF165 were determined by enzyme-linked immunosorbent assay (ELISA). After dyed with hematoxylin-eosin (HE), the lung tissue pathology was observed and the lung injury score was performed. Compared with the ALI model group, the arterial partial pressure of oxygen (PaO 2 ) in EPCs, none transfected EPCs and VEGF165 transfected EPCs treatment groups was significantly increased from 4 hours, and lung W/D, expressions of iNOS and ET-1 were significantly decreased, and VEGF165 expression was significantly increased. Compared with the EPCs treatment group, the increase in PaO 2 , the decrease in lung W/D and expressions of iNOS and ET-1, and the increase in VEGF165 expression in VEGF165 transfected EPCs

Magnetizable stent-grafts enable endothelial cell capture

Science.gov (United States)

Tefft, Brandon J.; Uthamaraj, Susheil; Harburn, J. Jonathan; Hlinomaz, Ota; Lerman, Amir; Dragomir-Daescu, Dan; Sandhu, Gurpreet S.

2017-04-01

Emerging nanotechnologies have enabled the use of magnetic forces to guide the movement of magnetically-labeled cells, drugs, and other therapeutic agents. Endothelial cells labeled with superparamagnetic iron oxide nanoparticles (SPION) have previously been captured on the surface of magnetizable 2205 duplex stainless steel stents in a porcine coronary implantation model. Recently, we have coated these stents with electrospun polyurethane nanofibers to fabricate prototype stent-grafts. Facilitated endothelialization may help improve the healing of arteries treated with stent-grafts, reduce the risk of thrombosis and restenosis, and enable small-caliber applications. When placed in a SPION-labeled endothelial cell suspension in the presence of an external magnetic field, magnetized stent-grafts successfully captured cells to the surface regions adjacent to the stent struts. Implantation within the coronary circulation of pigs (n=13) followed immediately by SPION-labeled autologous endothelial cell delivery resulted in widely patent devices with a thin, uniform neointima and no signs of thrombosis or inflammation at 7 days. Furthermore, the magnetized stent-grafts successfully captured and retained SPION-labeled endothelial cells to select regions adjacent to stent struts and between stent struts, whereas the non-magnetized control stent-grafts did not. Early results with these prototype devices are encouraging and further refinements will be necessary in order to achieve more uniform cell capture and complete endothelialization. Once optimized, this approach may lead to more rapid and complete healing of vascular stent-grafts with a concomitant improvement in long-term device performance.

Characterization of a resident population of adventitial macrophage progenitor cells in postnatal vasculature.

Science.gov (United States)

Psaltis, Peter J; Puranik, Amrutesh S; Spoon, Daniel B; Chue, Colin D; Hoffman, Scott J; Witt, Tyra A; Delacroix, Sinny; Kleppe, Laurel S; Mueske, Cheryl S; Pan, Shuchong; Gulati, Rajiv; Simari, Robert D

2014-07-18

Macrophages regulate blood vessel structure and function in health and disease. The origins of tissue macrophages are diverse, with evidence for local production and circulatory renewal. We identified a vascular adventitial population containing macrophage progenitor cells and investigated their origins and fate. Single-cell disaggregates from adult C57BL/6 mice were prepared from different tissues and tested for their capacity to form hematopoietic colony-forming units. Aorta showed a unique predilection for generating macrophage colony-forming units. Aortic macrophage colony-forming unit progenitors coexpressed stem cell antigen-1 and CD45 and were adventitially located, where they were the predominant source of proliferating cells in the aortic wall. Aortic Sca-1(+)CD45(+) cells were transcriptionally and phenotypically distinct from neighboring cells lacking stem cell antigen-1 or CD45 and contained a proliferative (Ki67(+)) Lin(-)c-Kit(+)CD135(-)CD115(+)CX3CR1(+)Ly6C(+)CD11b(-) subpopulation, consistent with the immunophenotypic profile of macrophage progenitors. Adoptive transfer studies revealed that Sca-1(+)CD45(+) adventitial macrophage progenitor cells were not replenished via the circulation from bone marrow or spleen, nor was their prevalence diminished by depletion of monocytes or macrophages by liposomal clodronate treatment or genetic deficiency of macrophage colony-stimulating factor. Rather adventitial macrophage progenitor cells were upregulated in hyperlipidemic ApoE(-/-) and LDL-R(-/-) mice, with adventitial transfer experiments demonstrating their durable contribution to macrophage progeny particularly in the adventitia, and to a lesser extent the atheroma, of atherosclerotic carotid arteries. The discovery and characterization of resident vascular adventitial macrophage progenitor cells provides new insight into adventitial biology and its participation in atherosclerosis and provokes consideration of the broader existence of local macrophage

Endothelial cell proliferation in swine experimental aneurysm after coil embolization.

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Yumiko Mitome-Mishima

Full Text Available After coil embolization, recanalization in cerebral aneurysms adversely influences long-term prognosis. Proliferation of endothelial cells on the coil surface may reduce the incidence of recanalization and further improve outcomes after coil embolization. We aimed to map the expression of proliferating tissue over the aneurysmal orifice and define the temporal profile of tissue growth in a swine experimental aneurysm model. We compared the outcomes after spontaneous thrombosis with those of coil embolization using histological and morphological techniques. In aneurysms that we not coiled, spontaneous thrombosis was observed, and weak, easily detachable proliferating tissue was evident in the aneurysmal neck. In contrast, in the coil embolization group, histological analysis showed endothelial-like cells lining the aneurysmal opening. Moreover, immunohistochemical and morphological analysis suggested that these cells were immature endothelial cells. Our results indicated the existence of endothelial cell proliferation 1 week after coil embolization and showed immature endothelial cells in septal tissue between the systemic circulation and the aneurysm. These findings suggest that endothelial cells are lead to and proliferate in the former aneurysmal orifice. This is the first examination to evaluate the temporal change of proliferating tissue in a swine experimental aneurysm model.

CD13 is a novel mediator of monocytic/endothelial cell adhesion

DEFF Research Database (Denmark)

Mina-Osorio, Paola; Winnicka, Beata; O'Conor, Catherine

2008-01-01

During inflammation, cell surface adhesion molecules guide the adhesion and migration of circulating leukocytes across the endothelial cells lining the blood vessels to access the site of injury. The transmembrane molecule CD13 is expressed on monocytes and endothelial cells and has been shown...... to mediate homotypic cell adhesion, which may imply a role for CD13 in inflammatory monocyte trafficking. Here, we show that ligation and clustering of CD13 by mAb or viral ligands potently induce myeloid cell/endothelial adhesion in a signal transduction-dependent manner involving monocytic cytoskeletal...... rearrangement and filopodia formation. Treatment with soluble recombinant (r)CD13 blocks this CD13-dependent adhesion, and CD13 molecules from monocytic and endothelial cells are present in the same immunocomplex, suggesting a direct participation of CD13 in the adhesive interaction. This concept...

Human haemato-endothelial precursors: cord blood CD34+ cells produce haemogenic endothelium.

Directory of Open Access Journals (Sweden)

Elvira Pelosi

Full Text Available Embryologic and genetic evidence suggest a common origin of haematopoietic and endothelial lineages. In the murine embryo, recent studies indicate the presence of haemogenic endothelium and of a common haemato-endothelial precursor, the haemangioblast. Conversely, so far, little evidence supports the presence of haemogenic endothelium and haemangioblasts in later stages of development. Our studies indicate that human cord blood haematopoietic progenitors (CD34+45+144-, triggered by murine hepatocyte conditioned medium, differentiate into adherent proliferating endothelial precursors (CD144+CD105+CD146+CD31+CD45- capable of functioning as haemogenic endothelium. These cells, proven to give rise to functional vasculature in vivo, if further instructed by haematopoietic growth factors, first switch to transitional CD144+45+ cells and then to haematopoietic cells. These results highlight the plasticity of haemato-endhothelial precursors in human post-natal life. Furthermore, these studies may provide highly enriched populations of human post-fetal haemogenic endothelium, paving the way for innovative projects at a basic and possibly clinical level.

Magnetizable stent-grafts enable endothelial cell capture

Energy Technology Data Exchange (ETDEWEB)

Tefft, Brandon J. [Department of Cardiovascular Diseases, Mayo Clinic, Rochester, MN (United States); Uthamaraj, Susheil [Division of Engineering, Mayo Clinic, Rochester, MN (United States); Harburn, J. Jonathan [School of Medicine, Pharmacy and Health, Durham University, Stockton-on-Tees (United Kingdom); Hlinomaz, Ota [Department of Cardioangiology, St. Anne' s University Hospital, Brno (Czech Republic); Lerman, Amir [Department of Cardiovascular Diseases, Mayo Clinic, Rochester, MN (United States); Dragomir-Daescu, Dan [Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN (United States); Sandhu, Gurpreet S., E-mail: sandhu.gurpreet@mayo.edu [Department of Cardiovascular Diseases, Mayo Clinic, Rochester, MN (United States)

2017-04-01

Emerging nanotechnologies have enabled the use of magnetic forces to guide the movement of magnetically-labeled cells, drugs, and other therapeutic agents. Endothelial cells labeled with superparamagnetic iron oxide nanoparticles (SPION) have previously been captured on the surface of magnetizable 2205 duplex stainless steel stents in a porcine coronary implantation model. Recently, we have coated these stents with electrospun polyurethane nanofibers to fabricate prototype stent-grafts. Facilitated endothelialization may help improve the healing of arteries treated with stent-grafts, reduce the risk of thrombosis and restenosis, and enable small-caliber applications. When placed in a SPION-labeled endothelial cell suspension in the presence of an external magnetic field, magnetized stent-grafts successfully captured cells to the surface regions adjacent to the stent struts. Implantation within the coronary circulation of pigs (n=13) followed immediately by SPION-labeled autologous endothelial cell delivery resulted in widely patent devices with a thin, uniform neointima and no signs of thrombosis or inflammation at 7 days. Furthermore, the magnetized stent-grafts successfully captured and retained SPION-labeled endothelial cells to select regions adjacent to stent struts and between stent struts, whereas the non-magnetized control stent-grafts did not. Early results with these prototype devices are encouraging and further refinements will be necessary in order to achieve more uniform cell capture and complete endothelialization. Once optimized, this approach may lead to more rapid and complete healing of vascular stent-grafts with a concomitant improvement in long-term device performance. - Highlights: • Magnetic stent-grafts were made from 2205 steel stents and polyurethane nanofibers. • Stent-grafts remained patent and formed a thin and uniform neointima when implanted. • Stent-grafts captured endothelial cells labeled with magnetic nanoparticles. �

A continuum mathematical model of endothelial layer maintenance and senescence

Directory of Open Access Journals (Sweden)

Friedman Avner

2007-08-01

Full Text Available Abstract Background The monolayer of endothelial cells (ECs lining the inner wall of blood vessels deteriorates as a person ages due to a complex interplay of a variety of causes including cell death arising from shear stress of blood flow and cellular oxidative stress, cellular senescence, and decreased rate of replacement of dead ECs by progenitor stem cells. Results A continuum mathematical model is developed to describe the dynamics of large EC populations of the endothelium using a system of differential equations for the number densities of cells of different generations starting from endothelial progenitors to senescent cells, as well as the densities of dead cells and the holes created upon clearing dead cells. Aging of cells is manifested in three ways, namely, losing the ability to divide when the Hayflick limit of 50 generations is reached, decreasing replication rate parameters and increasing death rate parameters as cells divide; due to the dependence of these rate parameters on cell generation, the model predicts a narrow distribution of cell densities peaking at a particular cell generation. As the chronological age of a person advances, the peak of the distribution – corresponding to the age of the endothelium – moves towards senescence correspondingly. However, computer simulations also demonstrate that sustained and enhanced stem cell homing can halt the aging process of the endothelium by maintaining a stationary cell density distribution that peaks well before the Hayflick limit. The healing rates of damaged endothelia for young, middle-aged, and old persons are compared and are found to be particularly sensitive to the stem cell homing parameter. Conclusion The proposed model describes the aging of the endothelium as being driven by cellular senescence, with a rate that does not necessarily correspond to the chronological aging of a person. It is shown that the age of the endothelium depends sensitively on the homing

Design of biomimetic vascular grafts with magnetic endothelial patterning.

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Fayol, Delphine; Le Visage, Catherine; Ino, Julia; Gazeau, Florence; Letourneur, Didier; Wilhelm, Claire

2013-01-01

The development of small diameter vascular grafts with a controlled pluricellular organization is still needed for effective vascular tissue engineering. Here, we describe a technological approach combining a tubular scaffold and magnetically labeled cells to create a pluricellular and organized vascular graft, the endothelialization of which could be monitored by MRI prior to transplantation. A novel type of scaffold was developed with a tubular geometry and a porous bulk structure enabling the seeding of cells in the scaffold pores. A homogeneous distribution of human mesenchymal stem cells in the macroporous structure was obtained by seeding the freeze-dried scaffold with the cell suspension. The efficient covering of the luminal surface of the tube was then made possible thanks to the implementation of a magnetic-based patterning technique. Human endothelial cells or endothelial progenitors were magnetically labeled with iron oxide nanoparticles and successfully attracted to the 2-mm lumen where they attached and formed a continuous endothelium. The combination of imaging modalities [fluorescence imaging, histology, and 3D magnetic resonance imaging (MRI)] evidenced the integrity of the vascular construct. In particular, the observation of different cell organizations in a vascular scaffold within the range of resolution of single cells by 4.7 T MRI is reported.

Analysis of the receptor-mediated B19V mechanism of internalization in the endothelial B19V infection and adenovirus-mediated reactivation of B19V in endothelial cells

OpenAIRE

Pozzuto, Tanja

2012-01-01

Human Parvovirus B19 (B19V) is the causative agent of erythema infectiosum, hydrops fetalis, aplastic crises and polyarthritis. B19V displays a very narrow cell and tissue tropism with productive infection thought to be restricted exclusively to erythroid progenitor cells in the bone marrow and fetal liver. However, over the last years increasing evidence for the presence of B19V DNA in other cell types and tissues such as synovial fibroblasts, tonsilles and skin as well as endothelial cells ...

Circulating progenitor and angiogenic cell frequencies are abnormally static over pregnancy in women with preconception diabetes: A pilot study.

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Lima, Patricia D A; Chen, Zhilin; Tayab, Aysha; Murphy, Malia S Q; Pudwell, Jessica; Smith, Graeme N; Croy, B Anne

2017-01-01

Type 1 and 2 diabetes decrease the frequencies and functional capacities of circulating angiogenic cells (CAC). Diabetes also elevates gestational complications. These observations may be interrelated. We undertook pilot studies to address the hypothesis that preconception diabetes deviates known gestational increases in CACs. Cross-sectional study of type 1 diabetic, type 2 diabetic and normoglycemic pregnant women was conducted at 1st, 2nd, and 3rd trimester and compared to a 6mo postpartum surrogate baseline. Circulating progenitor cells (CPC; CD34+CD45dimSSlow) and CACs (CD34+CD45dimSSlow expressing CD133 without or with KDR) were quantified by flow cytometry and by colony assay (CFU-Hill). In pregnant normoglycemic women, CD34+CD45dimSSlow cell frequency was greater in 1st and 3rd trimester than postpartum but frequency of these cells was static over type 1 or 2 diabetic pregnancies. Type 1 and type 2 diabetic women showed CACs variance versus normal controls. Type 1 diabetic women had more total CD34+KDR+ CACs in 1st trimester and a higher ratio of CD133+KDR+ to total CD133+ cells in 1st and 2nd trimesters than control women, demonstrating an unbalance in CD133+KDR+ CACs. Type 2 diabetic women had more CD133+KDR+ CACs in 1st trimester and fewer CD133+KDR- CACs at mid-late pregnancy than normal pregnant women. Thus, pregnancy stage-specific physiological fluctuation in CPCs (CD34+) and CACs (CD133+KDR+ and CD133+KDR-) did not occur in type 1 and type 2 diabetic women. Early outgrowth colonies were stable across normal and diabetic pregnancies. Therefore, preconception diabetes blocks the normal dynamic pattern of CAC frequencies across gestation but does not alter colony growth. The differences between diabetic and typical women were seen at specific gestational stages that may be critical for initiation of the uterine vascular pathologies characterizing diabetic gestations.

Circulating progenitor and angiogenic cell frequencies are abnormally static over pregnancy in women with preconception diabetes: A pilot study.

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Patricia D A Lima

Full Text Available Type 1 and 2 diabetes decrease the frequencies and functional capacities of circulating angiogenic cells (CAC. Diabetes also elevates gestational complications. These observations may be interrelated. We undertook pilot studies to address the hypothesis that preconception diabetes deviates known gestational increases in CACs. Cross-sectional study of type 1 diabetic, type 2 diabetic and normoglycemic pregnant women was conducted at 1st, 2nd, and 3rd trimester and compared to a 6mo postpartum surrogate baseline. Circulating progenitor cells (CPC; CD34+CD45dimSSlow and CACs (CD34+CD45dimSSlow expressing CD133 without or with KDR were quantified by flow cytometry and by colony assay (CFU-Hill. In pregnant normoglycemic women, CD34+CD45dimSSlow cell frequency was greater in 1st and 3rd trimester than postpartum but frequency of these cells was static over type 1 or 2 diabetic pregnancies. Type 1 and type 2 diabetic women showed CACs variance versus normal controls. Type 1 diabetic women had more total CD34+KDR+ CACs in 1st trimester and a higher ratio of CD133+KDR+ to total CD133+ cells in 1st and 2nd trimesters than control women, demonstrating an unbalance in CD133+KDR+ CACs. Type 2 diabetic women had more CD133+KDR+ CACs in 1st trimester and fewer CD133+KDR- CACs at mid-late pregnancy than normal pregnant women. Thus, pregnancy stage-specific physiological fluctuation in CPCs (CD34+ and CACs (CD133+KDR+ and CD133+KDR- did not occur in type 1 and type 2 diabetic women. Early outgrowth colonies were stable across normal and diabetic pregnancies. Therefore, preconception diabetes blocks the normal dynamic pattern of CAC frequencies across gestation but does not alter colony growth. The differences between diabetic and typical women were seen at specific gestational stages that may be critical for initiation of the uterine vascular pathologies characterizing diabetic gestations.

Hug tightly and say goodbye: role of endothelial ICAM-1 in leukocyte transmigration.

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Rahman, Arshad; Fazal, Fabeha

2009-04-01

Stable adhesion of leukocytes to endothelium is crucial for transendothelial migration (TEM) of leukocytes evoked during inflammatory responses, immune surveillance, and homing and mobilization of hematopoietic progenitor cells. The basis of stable adhesion involves expression of intercellular adhesion molecule-1 (ICAM-1), an inducible endothelial adhesive protein that serves as a counter-receptor for beta(2)-integrins on leukocytes. Interaction of ICAM-1 with beta(2)-integrins enables leukocytes to adhere firmly to the vascular endothelium and subsequently, to migrate across the endothelial barrier. The emerging paradigm is that ICAM-1, in addition to firmly capturing leukocytes, triggers intracellular signaling events that may contribute to active participation of the endothelium in facilitating the TEM of adherent leukocytes. The nature, duration, and intensity of ICAM-1-dependent signaling events may contribute to the determination of the route (paracellular vs. transcellular) of leukocyte passage; these aspects of ICAM-1 signaling may in turn be influenced by density and distribution of ICAM-1 on the endothelial cell surface, the source of endothelial cells it is present on, and the type of leukocytes with which it is engaged. This review summarizes our current understanding of the "ICAM-1 paradigm" of TEM with an emphasis on the signaling events mediating ICAM-1 expression and activated by ICAM-1 engagement in endothelial cells.

Analysis of CD45- [CD34+/KDR+] endothelial progenitor cells as juvenile protective factors in a rat model of ischemic-hemorrhagic stroke.

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Julius L Decano

Full Text Available Identification of juvenile protective factors (JPFs which are altered with age and contribute to adult-onset diseases could identify novel pathways for reversing the effects of age, an accepted non-modifiable risk factor to adult-onset diseases. Since endothelial progenitor cells (EPCs have been observed to be altered in stroke, hypertension and hypercholesterolemia, said EPCs are candidate JPFs for adult-onset stroke. A priori, if EPC aging plays a 'master-switch JPF-role' in stroke pathogenesis, juvenile EPC therapy alone should delay stroke-onset. Using a hypertensive, transgenic-hyperlipidemic rat model of spontaneous ischemic-hemorrhagic stroke, spTg25, we tested the hypothesis that freshly isolated juvenile EPCs are JPFs that can attenuate stroke progression and delay stroke onset.FACS analysis revealed that CD45- [CD34+/KDR+] EPCs decrease with progression to stroke in spTg25 rats, exhibit differential expression of the dual endodthelin-1/VEGFsp receptor (DEspR and undergo differential DEspR-subtype specific changes in number and in vitro angiogenic tube-incorporation. In vivo EPC infusion of male, juvenile non-expanded cd45-[CD34+/KDR+] EPCs into female stroke-prone rats prior to stroke attenuated progression and delayed stroke onset (P<0.003. Detection of Y-chromosome DNA in brain microvessels of EPC-treated female spTg25 rats indicates integration of male EPCs into female rat brain microvessels. Gradient-echo MRI showed delay of ischemic-hemorrhagic lesions in EPC-treated rats. Real-time RT-PCR pathway-specific array-analysis revealed age-associated gene expression changes in CD45-[CD34+/KDR]EPC subtypes, which were accelerated in stroke-prone rats. Pro-angiogenic genes implicated in intimal hyperplasia were increased in stroke-prone rat EPCs (P<0.0001, suggesting a maladaptive endothelial repair system which acts like a double-edged sword repairing while predisposing to age-associated intimal hyperplasia.Altogether, the data

Constitutive expression of pluripotency-associated genes in mesodermal progenitor cells (MPCs.

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Simone Pacini

Full Text Available BACKGROUND: We recently characterized a progenitor of mesodermal lineage (MPCs from the human bone marrow of adults or umbilical cord blood. These cells are progenitors able to differentiate toward mesenchymal, endothelial and cardiomyogenic lineages. Here we present an extensive molecular characterization of MPCs, from bone marrow samples, including 39 genes involved in stem cell machinery, differentiation and cell cycle regulation. METHODOLOGY/PRINCIPAL FINDINGS: MPCs are cytofluorimetrically characterized and quantitative RT-PCR was performed to evaluate the gene expression profile, comparing it with MSCs and hESCs lines. Immunofluorescence and dot-blot analysis confirm qRT-PCR data. MPCs exhibit an increased expression of OCT4, NANOG, SALL4, FBX15, SPP1 and to a lesser extent c-MYC and KLF4, but lack LIN28 and SOX2. MPCs highly express SOX15. CONCLUSIONS/SIGNIFICANCE: MPCs express many pluripotency-associated genes and show a peculiar Oct-4 molecular circuit. Understanding this unique molecular mechanism could lead to identifying MPCs as feasible, long telomeres, target cells for reprogramming with no up-regulation of the p53 pathway. Furthermore MPCs are easily and inexpensively harvested from human bone marrow.

Endothelial biocompatibility and accumulation of SPION under flow conditions

International Nuclear Information System (INIS)

Matuszak, Jasmin; Zaloga, Jan; Friedrich, Ralf P.; Lyer, Stefan; Nowak, Johannes; Odenbach, Stefan; Alexiou, Christoph; Cicha, Iwona

2015-01-01

Magnetic targeting is considered a promising method to accumulate the nanoparticles at the sites of atherosclerotic lesions, but little is known about the biological effects of magnetic nanoparticles on the vascular wall. Here, we investigated endothelial cell growth and vitality upon treatment with SPION (0–60 µg/mL) using two complementing methods: real-time cell analysis and live-cell microscopy. Moreover, the uptake of circulating superparamagnetic iron oxide nanoparticles (SPIONs) was assessed in an in vitro model of arterial bifurcations. At the tested concentrations, SPIONs were well tolerated and had no major influence on endothelial cell growth. Our results further showed a uniform distribution of endothelial SPION uptake independent of channel geometry or hemodynamic conditions: In the absence of magnetic force, no increase in accumulation of SPIONs at non-uniform shear stress region at the outer walls of bifurcation was observed. Application of external magnet allowed enhanced accumulation of SPIONs at the regions of non-uniform shear stress. Increased uptake of SPIONs at non-uniform shear stress region was well tolerated by endothelial cells (ECs) and did not affect endothelial cell viability or attachment. These findings indicate that magnetic targeting can constitute a promising and safe technique for the delivery of imaging and therapeutic nanoparticles to atherosclerotic lesions

Endothelial biocompatibility and accumulation of SPION under flow conditions

Energy Technology Data Exchange (ETDEWEB)

Matuszak, Jasmin; Zaloga, Jan; Friedrich, Ralf P.; Lyer, Stefan [Section of Experimental Oncology and Nanomedicine (SEON), Else Kröner-Fresenius Stiftungsprofessur for Nanomedicine, University Hospital Erlangen, Erlangen (Germany); Nowak, Johannes; Odenbach, Stefan [Chair of Magnetofluiddynamics, Measuring and Automation Technology, Technische Universität Dresden, Dresden (Germany); Alexiou, Christoph [Section of Experimental Oncology and Nanomedicine (SEON), Else Kröner-Fresenius Stiftungsprofessur for Nanomedicine, University Hospital Erlangen, Erlangen (Germany); Cicha, Iwona, E-mail: Iwona_Cicha@yahoo.com [Section of Experimental Oncology and Nanomedicine (SEON), Else Kröner-Fresenius Stiftungsprofessur for Nanomedicine, University Hospital Erlangen, Erlangen (Germany)

2015-04-15

Magnetic targeting is considered a promising method to accumulate the nanoparticles at the sites of atherosclerotic lesions, but little is known about the biological effects of magnetic nanoparticles on the vascular wall. Here, we investigated endothelial cell growth and vitality upon treatment with SPION (0–60 µg/mL) using two complementing methods: real-time cell analysis and live-cell microscopy. Moreover, the uptake of circulating superparamagnetic iron oxide nanoparticles (SPIONs) was assessed in an in vitro model of arterial bifurcations. At the tested concentrations, SPIONs were well tolerated and had no major influence on endothelial cell growth. Our results further showed a uniform distribution of endothelial SPION uptake independent of channel geometry or hemodynamic conditions: In the absence of magnetic force, no increase in accumulation of SPIONs at non-uniform shear stress region at the outer walls of bifurcation was observed. Application of external magnet allowed enhanced accumulation of SPIONs at the regions of non-uniform shear stress. Increased uptake of SPIONs at non-uniform shear stress region was well tolerated by endothelial cells (ECs) and did not affect endothelial cell viability or attachment. These findings indicate that magnetic targeting can constitute a promising and safe technique for the delivery of imaging and therapeutic nanoparticles to atherosclerotic lesions.

Differentiation of Human Pluripotent Stem Cells into Functional Endothelial Cells in Scalable Suspension Culture

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Ruth Olmer

2018-05-01

Full Text Available Summary: Endothelial cells (ECs are involved in a variety of cellular responses. As multifunctional components of vascular structures, endothelial (progenitor cells have been utilized in cellular therapies and are required as an important cellular component of engineered tissue constructs and in vitro disease models. Although primary ECs from different sources are readily isolated and expanded, cell quantity and quality in terms of functionality and karyotype stability is limited. ECs derived from human induced pluripotent stem cells (hiPSCs represent an alternative and potentially superior cell source, but traditional culture approaches and 2D differentiation protocols hardly allow for production of large cell numbers. Aiming at the production of ECs, we have developed a robust approach for efficient endothelial differentiation of hiPSCs in scalable suspension culture. The established protocol results in relevant numbers of ECs for regenerative approaches and industrial applications that show in vitro proliferation capacity and a high degree of chromosomal stability. : In this article, U. Martin and colleagues show the generation of hiPSC endothelial cells in scalable cultures in up to 100 mL culture volume. The generated ECs show in vitro proliferation capacity and a high degree of chromosomal stability after in vitro expansion. The established protocol allows to generate hiPSC-derived ECs in relevant numbers for regenerative approaches. Keywords: hiPSC differentiation, endothelial cells, scalable culture

Hypoxia inducible factor-2α regulates the development of retinal astrocytic network by maintaining adequate supply of astrocyte progenitors.

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Li-Juan Duan

Full Text Available Here we investigate the role of hypoxia inducible factor (HIF-2α in coordinating the development of retinal astrocytic and vascular networks. Three Cre mouse lines were used to disrupt floxed Hif-2α, including Rosa26(CreERT2, Tie2(Cre, and GFAP(Cre. Global Hif-2α disruption by Rosa26(CreERT2 led to reduced astrocytic and vascular development in neonatal retinas, whereas endothelial disruption by Tie2(Cre had no apparent effects. Hif-2α deletion in astrocyte progenitors by GFAP(Cre significantly interfered with the development of astrocytic networks, which failed to reach the retinal periphery and were incapable of supporting vascular development. Perplexingly, the abundance of strongly GFAP(+ mature astrocytes transiently increased at P0 before they began to lag behind the normal controls by P3. Pax2(+ and PDGFRα(+ astrocytic progenitors and immature astrocytes were dramatically diminished at all stages examined. Despite decreased number of astrocyte progenitors, their proliferation index or apoptosis was not altered. The above data can be reconciled by proposing that HIF-2α is required for maintaining the supply of astrocyte progenitors by slowing down their differentiation into non-proliferative mature astrocytes. HIF-2α deficiency in astrocyte progenitors may accelerate their differentiation into astrocytes, a change which greatly interferes with the replenishment of astrocyte progenitors due to insufficient time for proliferation. Rapidly declining progenitor supply may lead to premature cessation of astrocyte development. Given that HIF-2α protein undergoes oxygen dependent degradation, an interesting possibility is that retinal blood vessels may regulate astrocyte differentiation through their oxygen delivery function. While our findings support the consensus that retinal astrocytic template guides vascular development, they also raise the possibility that astrocytic and vascular networks may mutually regulate each other

Reduced Erg Dosage Impairs Survival of Hematopoietic Stem and Progenitor Cells.

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Xie, Ying; Koch, Mia Lee; Zhang, Xin; Hamblen, Melanie J; Godinho, Frank J; Fujiwara, Yuko; Xie, Huafeng; Klusmann, Jan-Henning; Orkin, Stuart H; Li, Zhe

2017-07-01

ERG, an ETS family transcription factor frequently overexpressed in human leukemia, has been implicated as a key regulator of hematopoietic stem cells. However, how ERG controls normal hematopoiesis, particularly at the stem and progenitor cell level, and how it contributes to leukemogenesis remain incompletely understood. Using homologous recombination, we generated an Erg knockdown allele (Erg kd ) in which Erg expression can be conditionally restored by Cre recombinase. Erg kd/kd animals die at E10.5-E11.5 due to defects in endothelial and hematopoietic cells, but can be completely rescued by Tie2-Cre-mediated restoration of Erg in these cells. In Erg kd/+ mice, ∼40% reduction in Erg dosage perturbs both fetal liver and bone marrow hematopoiesis by reducing the numbers of Lin - Sca-1 + c-Kit + (LSK) hematopoietic stem and progenitor cells (HSPCs) and megakaryocytic progenitors. By genetic mosaic analysis, we find that Erg-restored HSPCs outcompete Erg kd/+ HSPCs for contribution to adult hematopoiesis in vivo. This defect is in part due to increased apoptosis of HSPCs with reduced Erg dosage, a phenotype that becomes more drastic during 5-FU-induced stress hematopoiesis. Expression analysis reveals that reduced Erg expression leads to changes in expression of a subset of ERG target genes involved in regulating survival of HSPCs, including increased expression of a pro-apoptotic regulator Bcl2l11 (Bim) and reduced expression of Jun. Collectively, our data demonstrate that ERG controls survival of HSPCs, a property that may be used by leukemic cells. Stem Cells 2017;35:1773-1785. © 2017 AlphaMed Press.

Absences of Endothelial Microvesicle Changes in the Presence of the Endotheliopathy of Trauma

DEFF Research Database (Denmark)

Wade, Charles E; Matijevic, Nena; Wang, Yao-Wei W

2018-01-01

thrombomodulin levels. Based on thrombelastography, EOT had reductions in clot initiation, amplification, propagation and strength, and a greater frequency of transfusion, 92% vs 33%. There were no differences in EMVs irrespective of the antibody used. Plasma norepinephrine, sE-selectin, sVE-cadherin and histone....... Endothelial microvesicles (EMVs) represent cellular damage. We hypothesized that EOT is associated with endothelial damage and apoptosis resulting in an increase in circulating EMVs. METHODS: Prospective, observational study enrolling severely injured patients. Twelve patients with EOT, based on elevated...... by flow cytometry using varied monoclonal antibodies associated with endothelial cells. Significance was set at p Syndecan-1, 230 (158, 293) vs. 19 (14, 25) ng/ml, epinephrine and soluble...

Identification of MicroRNA-124 as a Major Regulator of Enhanced Endothelial Cell Glycolysis in Pulmonary Arterial Hypertension via PTBP1 (Polypyrimidine Tract Binding Protein) and Pyruvate Kinase M2.

Science.gov (United States)

Caruso, Paola; Dunmore, Benjamin J; Schlosser, Kenny; Schoors, Sandra; Dos Santos, Claudia; Perez-Iratxeta, Carol; Lavoie, Jessie R; Zhang, Hui; Long, Lu; Flockton, Amanda R; Frid, Maria G; Upton, Paul D; D'Alessandro, Angelo; Hadinnapola, Charaka; Kiskin, Fedir N; Taha, Mohamad; Hurst, Liam A; Ormiston, Mark L; Hata, Akiko; Stenmark, Kurt R; Carmeliet, Peter; Stewart, Duncan J; Morrell, Nicholas W

2017-12-19

circulating progenitor endothelial cells isolated from patients with PAH demonstrate downregulation of miR-124, leading to the metabolic and proliferative abnormalities in PAH ECs via PTPB1 and PKM1/PKM2. Therefore, the manipulation of this miRNA or its targets could represent a novel therapeutic approach for the treatment of PAH. © 2017 American Heart Association, Inc.

Neurotrophins promote revascularization by local recruitment of TrkB+ endothelial cells and systemic mobilization of hematopoietic progenitors

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Kermani, Pouneh; Rafii, Dahlia; Jin, David K.; Whitlock, Paul; Schaffer, Wendy; Chiang, Anne; Vincent, Loic; Friedrich, Matthias; Shido, Koji; Hackett, Neil R.; Crystal, Ronald G.; Rafii, Shahin; Hempstead, Barbara L.

2005-01-01

The neurotrophin brain-derived neurotrophic factor (BDNF) is required for the maintenance of cardiac vessel wall stability during embryonic development through direct angiogenic actions on endothelial cells expressing the tropomysin receptor kinase B (TrkB). However, the role of BDNF and a related neurotrophin ligand, neurotrophin-4 (NT-4), in the regulation of revascularization of the adult tissues is unknown. To study the potential angiogenic capacity of BDNF in mediating the neovascularization of ischemic and non-ischemic adult mouse tissues, we utilized a hindlimb ischemia and a subcutaneous Matrigel model. Recruitment of endothelial cells and promotion of channel formation within the Matrigel plug by BDNF and NT-4 was comparable to that induced by VEGF-A. The introduction of BDNF into non-ischemic ears or ischemic limbs induced neoangiogenesis, with a 2-fold increase in the capillary density. Remarkably, treatment with BDNF progressively increased blood flow in the ischemic limb over 21 days, similar to treatment with VEGF-A. The mechanism by which BDNF enhances capillary formation is mediated in part through local activation of the TrkB receptor and also by recruitment of Sca-1+CD11b+ pro-angiogenic hematopoietic cells. BDNF induces a potent direct chemokinetic action on subsets of marrow-derived Sca-1+ hematopoietic cells co-expressing TrkB. These studies suggest that local regional delivery of BDNF may provide a novel mechanism for inducing neoangiogenesis through both direct actions on local TrkB-expressing endothelial cells in skeletal muscle and recruitment of specific subsets of TrkB+ bone marrow–derived hematopoietic cells to provide peri-endothelial support for the newly formed vessels. PMID:15765148

Gene expression analysis of embryonic stem cells expressing VE-cadherin (CD144 during endothelial differentiation

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Libermann Towia

2008-05-01

Full Text Available Abstract Background Endothelial differentiation occurs during normal vascular development in the developing embryo. This process is recapitulated in the adult when endothelial progenitor cells are generated in the bone marrow and can contribute to vascular repair or angiogenesis at sites of vascular injury or ischemia. The molecular mechanisms of endothelial differentiation remain incompletely understood. Novel approaches are needed to identify the factors that regulate endothelial differentiation. Methods Mouse embryonic stem (ES cells were used to further define the molecular mechanisms of endothelial differentiation. By flow cytometry a population of VEGF-R2 positive cells was identified as early as 2.5 days after differentiation of ES cells, and a subset of VEGF-R2+ cells, that were CD41 positive at 3.5 days. A separate population of VEGF-R2+ stem cells expressing the endothelial-specific marker CD144 (VE-cadherin was also identified at this same time point. Channels lined by VE-cadherin positive cells developed within the embryoid bodies (EBs formed by differentiating ES cells. VE-cadherin and CD41 expressing cells differentiate in close proximity to each other within the EBs, supporting the concept of a common origin for cells of hematopoietic and endothelial lineages. Results Microarray analysis of >45,000 transcripts was performed on RNA obtained from cells expressing VEGF-R2+, CD41+, and CD144+ and VEGF-R2-, CD41-, and CD144-. All microarray experiments were performed in duplicate using RNA obtained from independent experiments, for each subset of cells. Expression profiling confirmed the role of several genes involved in hematopoiesis, and identified several putative genes involved in endothelial differentiation. Conclusion The isolation of CD144+ cells during ES cell differentiation from embryoid bodies provides an excellent model system and method for identifying genes that are expressed during endothelial differentiation and that

Factors Released from Endothelial Cells Exposed to Flow Impact Adhesion, Proliferation, and Fate Choice in the Adult Neural Stem Cell Lineage.

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Dumont, Courtney M; Piselli, Jennifer M; Kazi, Nadeem; Bowman, Evan; Li, Guoyun; Linhardt, Robert J; Temple, Sally; Dai, Guohao; Thompson, Deanna M

2017-08-15

The microvasculature within the neural stem cell (NSC) niche promotes self-renewal and regulates lineage progression. Previous work identified endothelial-produced soluble factors as key regulators of neural progenitor cell (NPC) fate and proliferation; however, endothelial cells (ECs) are sensitive to local hemodynamics, and the effect of this key physiological process has not been defined. In this study, we evaluated adult mouse NPC response to soluble factors isolated from static or dynamic (flow) EC cultures. Endothelial factors generated under dynamic conditions significantly increased neuronal differentiation, while those released under static conditions stimulated oligodendrocyte differentiation. Flow increases EC release of neurogenic factors and of heparin sulfate glycosaminoglycans that increase their bioactivity, likely underlying the enhanced neuronal differentiation. Additionally, endothelial factors, especially from static conditions, promoted adherent growth. Together, our data suggest that blood flow may impact proliferation, adhesion, and the neuron-glial fate choice of adult NPCs, with implications for diseases and aging that reduce flow.

Isolation and characterization of human umbilical cord-derived endothelial colony-forming cells

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Zhang, Hao; Tao, Yanling; Ren, Saisai; Liu, Haihui; Zhou, Hui; Hu, Jiangwei; Tang, Yongyong; Zhang, Bin; Chen, Hu

2017-01-01

Endothelial colony-forming cells (ECFCs) are a population of endothelial progenitor cells (EPCs) that display robust proliferative potential and vessel-forming capability. Previous studies have demonstrated that a limited number of ECFCs may be obtained from adult bone marrow, peripheral blood and umbilical cord (UC) blood. The present study describes an effective method for isolating ECFCs from human UC. The ECFCs derived from human UC displayed the full properties of EPCs. Analysis of the growth kinetics, cell cycle and colony-forming ability of the isolated human UC-ECFCs indicated that the cells demonstrated properties of stem cells, including relative stability and rapid proliferation in vitro. Gene expression of Fms related tyrosine kinase 1, kinase insert domain receptor, vascular endothelial cadherin, cluster of differentiation (CD)31, CD34, epidermal growth factor homology domains-2, von Willebrand factor and endothelial nitric oxide synthase was assessed by reverse transcription-polymerase chain reaction. The cells were positive for CD34, CD31, CD73, CD105 and vascular endothelial growth factor receptor-2, and negative for CD45, CD90 and human leukocyte antigen-antigen D related protein according to flow cytometry. 1,1′-dioctadecyl-3,3,3′,3′-tetra-methyl-indocarbocyanine perchlorate-labeled acetylated low-density lipoprotein and fluorescein isothiocyanate-Ulex europaeus-l were used to verify the identity of the UC-ECFCs. Matrigel was used to investigate tube formation capability. The results demonstrated that the reported technique is a valuable method for isolating human UC-ECFCs, which have potential for use in vascular regeneration. PMID:29067104

High Density Sphere Culture of Adult Cardiac Cells Increases the Levels of Cardiac and Progenitor Markers and Shows Signs of Vasculogenesis

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Kristina Vukusic

2013-01-01

Full Text Available 3D environment and high cell density play an important role in restoring and supporting the phenotypes of cells represented in cardiac tissues. The aim of this study was therefore to investigate the suitability of high density sphere (HDS cultures for studies of cardiomyocyte-, endothelial-, and stem-cell biology. Primary adult cardiac cells from nine human biopsies were cultured using different media for up to 9 weeks. The possibilities to favor a certain cell phenotype and induce production of extra cellular matrix (ECM were studied by histology, immunohistochemistry, and quantitative real-time PCR. Defined media gave significant increase in both cardiac- and progenitor-specific markers and also an intraluminal position of endothelial cells over time. Cardiac media showed indication of differentiation and maturity of HDS considering the ECM production and activities within NOTCH regulation but no additional cardiac differentiation. Endothelial media gave no positive effects on endothelial phenotype but increased proliferation without fibroblast overgrowth. In addition, indications for early vasculogenesis were found. It was also possible to affect the Wnt signaling in HDS by addition of a glycogen synthase kinase 3 (GSK3 inhibitor. In conclusion, these findings show the suitability of HDS as in vitro model for studies of cardiomyocyte-, endothelial-, and stem-cell biology.

Endothelial adhesion molecules and leukocyte integrins in preeclamptic patients.

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Haller, H; Ziegler, E M; Homuth, V; Drab, M; Eichhorn, J; Nagy, Z; Busjahn, A; Vetter, K; Luft, F C

1997-01-01

Endothelial cell activation is important in the pathogenesis of preeclampsia; however, the nature of the activation is unknown. We investigated 22 patients with preeclampsia. 29 normotensive pregnancies, and 18 nonpregnant women to test the hypothesis that serum from preeclamptic patients induces expression of intercellular adhesion molecule-1 (ICAM-1) and vascular adhesion molecule-1 (VCAM-1) and stimulates intracellular free calcium concentrations [Ca2+]i in cultured endothelial cells. We then asked whether the corresponding integrin adhesive counter receptors lymphocyte function-associated antigen-1 (CD11a/CD18), macrophage-1 antigen (CD11b/CD18), p150,95 (CD11c/CD18), and very late activation antigen-4 (CD49/CD29) are increased in patients with preeclampsia. In the pregnant women, the measurements were conducted both before and after delivery. Integrin expression was measured by fluorescent antibody cell sorting analysis using monoclonal antibodies. ICAM-1 and VCAM-1 were analyzed on endothelial cells by enzyme-linked immunosorbent assay. [Ca2+]i was measured with fura 2. Serum from preeclamptic patients increased endothelial cell ICAM-1 expression but not VCAM-1 expression. Preeclamptic patients' serum also increased [Ca2+]i in endothelial cells compared with serum from normal nonpregnant or normal pregnant women. Endothelial cell [Ca2+]i concentrations were correlated with the ICAM-1 expression in preeclamptic patients (r = .80, P preclampsia and normal pregnancy compared with the nonpregnant state. The expression decreased significantly after delivery in both groups. Our results demonstrate that serum from preeclamptic women induces increased ICAM-1 surface expression on endothelial cells, while the expression of the integrin counterreceptors was not different. The effect on endothelial cells may be related to an increase in [Ca2+]i. The effect on cultured endothelial cells and the rapid decrease after delivery suggests the presence of a circulating serum

Neural Progenitors Adopt Specific Identities by Directly Repressing All Alternative Progenitor Transcriptional Programs.

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Kutejova, Eva; Sasai, Noriaki; Shah, Ankita; Gouti, Mina; Briscoe, James

2016-03-21

In the vertebrate neural tube, a morphogen-induced transcriptional network produces multiple molecularly distinct progenitor domains, each generating different neuronal subtypes. Using an in vitro differentiation system, we defined gene expression signatures of distinct progenitor populations and identified direct gene-regulatory inputs corresponding to locations of specific transcription factor binding. Combined with targeted perturbations of the network, this revealed a mechanism in which a progenitor identity is installed by active repression of the entire transcriptional programs of other neural progenitor fates. In the ventral neural tube, sonic hedgehog (Shh) signaling, together with broadly expressed transcriptional activators, concurrently activates the gene expression programs of several domains. The specific outcome is selected by repressive input provided by Shh-induced transcription factors that act as the key nodes in the network, enabling progenitors to adopt a single definitive identity from several initially permitted options. Together, the data suggest design principles relevant to many developing tissues. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Impact of adipose tissue or umbilical cord derived mesenchymal stem cells on the immunogenicity of human cord blood derived endothelial progenitor cells.

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Kefang Tan

Full Text Available The application of autologous endothelial progenitor cell (EPC transplantation is a promising approach in therapeutic cardiovascular diseases and ischemic diseases. In this study, we compared the immunogenicity of EPCs, adipose tissue (AD-derived mesenchymal stem cells (MSCs and umbilical cord (UC-derived MSCs by flow cytometry and the mixed lymphocyte reaction. The impact of AD-MSCs and UC-MSCs on the immunogenicity of EPCs was analyzed by the mixed lymphocyte reaction and cytokine secretion in vitro and was further tested by allogenic peripheral blood mononuclear cell (PBMC induced immuno-rejection on a cell/matrigel graft in an SCID mouse model. EPCs and AD-MSCs express higher levels of MHC class I than UC-MSCs. All three kinds of cells are negative for MHC class II. UC-MSCs also express lower levels of IFN-γ receptor mRNA when compared with EPCs and AD-MSCs. EPCs can stimulate higher rates of proliferation of lymphocytes than AD-MSCs and UC-MSCs. Furthermore, AD-MSCs and UC-MSCs can modulate immune response and inhibit lymphocyte proliferation induced by EPCs, mainly through inhibition of the proliferation of CD8+ T cells. Compared with UC-MSCs, AD-MSCs can significantly improve vessel formation and maintain the integrity of neovascular structure in an EPC+MSC/matrigel graft in SCID mice, especially under allo-PBMC induced immuno-rejection. In conclusion, our study shows that AD-MSC is a powerful candidate to minimize immunological rejection and improve vessel formation in EPC transplantation treatment.

Dynamics of bone marrow-derived endothelial progenitor cell/mesenchymal stem cell interaction in co-culture and its implications in angiogenesis

International Nuclear Information System (INIS)

Aguirre, A.; Planell, J.A.; Engel, E.

2010-01-01

Research highlights: → BM-EPCs and MSCs establish complex, self-organizing structures in co-culture. → Co-culture decreases proliferation by cellular self-regulatory mechanisms. → Co-cultured cells present an activated proangiogenic phenotype. → qRT-PCR and cluster analysis identify new target genes playing important roles. -- Abstract: Tissue engineering aims to regenerate tissues and organs by using cell and biomaterial-based approaches. One of the current challenges in the field is to promote proper vascularization in the implant to prevent cell death and promote host integration. Bone marrow endothelial progenitor cells (BM-EPCs) and mesenchymal stem cells (MSCs) are bone marrow resident stem cells widely employed for proangiogenic applications. In vivo, they are likely to interact frequently both in the bone marrow and at sites of injury. In this study, the physical and biochemical interactions between BM-EPCs and MSCs in an in vitro co-culture system were investigated to further clarify their roles in vascularization. BM-EPC/MSC co-cultures established close cell-cell contacts soon after seeding and self-assembled to form elongated structures at 3 days. Besides direct contact, cells also exhibited vesicle transport phenomena. When co-cultured in Matrigel, tube formation was greatly enhanced even in serum-starved, growth factor free medium. Both MSCs and BM-EPCs contributed to these tubes. However, cell proliferation was greatly reduced in co-culture and morphological differences were observed. Gene expression and cluster analysis for wide panel of angiogenesis-related transcripts demonstrated up-regulation of angiogenic markers but down-regulation of many other cytokines. These data suggest that cross-talk occurs in between BM-EPCs and MSCs through paracrine and direct cell contact mechanisms leading to modulation of the angiogenic response.

Vascular Ageing and Exercise: Focus on Cellular Reparative Processes.

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Ross, Mark D; Malone, Eva; Florida-James, Geraint

2016-01-01

Ageing is associated with an increased risk of developing noncommunicable diseases (NCDs), such as diabetes and cardiovascular disease (CVD). The increased risk can be attributable to increased prolonged exposure to oxidative stress. Often, CVD is preceded by endothelial dysfunction, which carries with it a proatherothrombotic phenotype. Endothelial senescence and reduced production and release of nitric oxide (NO) are associated with "vascular ageing" and are often accompanied by a reduced ability for the body to repair vascular damage, termed "reendothelialization." Exercise has been repeatedly shown to confer protection against CVD and diabetes risk and incidence. Regular exercise promotes endothelial function and can prevent endothelial senescence, often through a reduction in oxidative stress. Recently, endothelial precursors, endothelial progenitor cells (EPC), have been shown to repair damaged endothelium, and reduced circulating number and/or function of these cells is associated with ageing. Exercise can modulate both number and function of these cells to promote endothelial homeostasis. In this review we look at the effects of advancing age on the endothelium and these endothelial precursors and how exercise appears to offset this "vascular ageing" process.

In vivo bio-distribution and homing of endothelial outgrowth cells in a tumour model

International Nuclear Information System (INIS)

Bertelsen, Lotte B.; Hagensen, Mette; Busk, Morten; Zhang, Rui; Knudsen, Anne S.; Nielsen, Nathalie; Falborg, Lise; Møller, Bjarne K.; Horsman, Michael R.; Stødkilde-Jørgensen, Hans

2014-01-01

Introduction: Endothelial progenitor cells (EPCs) has been reported to have the potential for advancing revascularization of ischemic tissue. However, the heterogeneous nature of these cells calls for specification of the angiogenic potential of each subtype. The purpose of this study was to gain additional insight on the homing capacity of the EPC subtype, endothelial outgrowth cells (EOCs) in tumours using a well-established tumour model. Methods: 111 Indium ( 111 In) – and 5-(and-6)-carboxyfluorescein diacetate succinimidyl ester (CFSE) labelled EOCs derived from human umbilical cord blood were injected into mice with a C3H mammary carcinoma foot tumour. The subsequent capture of the EOCs was traced by estimation of activity in individual organs, autoradiography and fluorescence microscopy. Results: 111 In activity was found in tumour and other organs. However, varying parts of the activity originated from free 111 In lost from EOCs. Autoradiography demonstrated accumulation of 111 In activity in the tumour rim. Microscopy proved that a least part of this radioactivity originated from the presence of human derived EOCs and that those EOCs were not located in the endothelial lining of vessels, in the tumour. Conclusion: The results demonstrated the presence of xenotransplanted EOCs in the rim of a C3H mammary carcinoma. They were, however, not located in the endothelial lining of the vessels, thus indicating that their effect in vasculogenesis might be mediated via paracrine mechanisms rather than differentiating into endothelial cells (ECs) in tumour vessels

Expansion of Adult Human Pancreatic Tissue Yields Organoids Harboring Progenitor Cells with Endocrine Differentiation Potential

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Cindy J.M. Loomans

2018-03-01

Full Text Available Summary: Generating an unlimited source of human insulin-producing cells is a prerequisite to advance β cell replacement therapy for diabetes. Here, we describe a 3D culture system that supports the expansion of adult human pancreatic tissue and the generation of a cell subpopulation with progenitor characteristics. These cells display high aldehyde dehydrogenase activity (ALDHhi, express pancreatic progenitors markers (PDX1, PTF1A, CPA1, and MYC, and can form new organoids in contrast to ALDHlo cells. Interestingly, gene expression profiling revealed that ALDHhi cells are closer to human fetal pancreatic tissue compared with adult pancreatic tissue. Endocrine lineage markers were detected upon in vitro differentiation. Engrafted organoids differentiated toward insulin-positive (INS+ cells, and circulating human C-peptide was detected upon glucose challenge 1 month after transplantation. Engrafted ALDHhi cells formed INS+ cells. We conclude that adult human pancreatic tissue has potential for expansion into 3D structures harboring progenitor cells with endocrine differentiation potential. : In the context of β cell replacement therapy for diabetes, de Koning and colleagues describe a 3D culture platform that supports ex vivo expansion of human pancreatic tissue as organoids. These organoids harbor a subpopulation of ALDHhi cells that display proliferative capacity and can differentiate to an endocrine fate. Keywords: pancreas, organoid, human, ALDH, endocrine differentiation, beta cells, insulin, progenitor, fetal, diabetes

Hematopoietic stem and progenitor cells regulate the regeneration of their niche by secreting Angiopoietin-1

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Zhou, Bo O; Ding, Lei; Morrison, Sean J

2015-01-01

Hematopoietic stem cells (HSCs) are maintained by a perivascular niche in bone marrow but it is unclear whether the niche is reciprocally regulated by HSCs. Here, we systematically assessed the expression and function of Angiopoietin-1 (Angpt1) in bone marrow. Angpt1 was not expressed by osteoblasts. Angpt1 was most highly expressed by HSCs, and at lower levels by c-kit+ hematopoietic progenitors, megakaryocytes, and Leptin Receptor+ (LepR+) stromal cells. Global conditional deletion of Angpt1, or deletion from osteoblasts, LepR+ cells, Nes-cre-expressing cells, megakaryocytes, endothelial cells or hematopoietic cells in normal mice did not affect hematopoiesis, HSC maintenance, or HSC quiescence. Deletion of Angpt1 from hematopoietic cells and LepR+ cells had little effect on vasculature or HSC frequency under steady-state conditions but accelerated vascular and hematopoietic recovery after irradiation while increasing vascular leakiness. Hematopoietic stem/progenitor cells and LepR+ stromal cells regulate niche regeneration by secreting Angpt1, reducing vascular leakiness but slowing niche recovery. DOI: http://dx.doi.org/10.7554/eLife.05521.001 PMID:25821987

Highly efficient local delivery of endothelial progenitor cells significantly potentiates angiogenesis and full-thickness wound healing.

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Wang, Chenggui; Wang, Qingqing; Gao, Wendong; Zhang, Zengjie; Lou, Yiting; Jin, Haiming; Chen, Xiaofeng; Lei, Bo; Xu, Huazi; Mao, Cong

2018-03-15

Wound therapy with a rapid healing performance remains a critical clinical challenge. Cellular delivery is considered to be a promising approach to improve the efficiency of healing, yet problems such as compromised cell viability and functionality arise due to the inefficient delivery. Here, we report the efficient delivery of endothelial progenitor cells (EPCs) with a bioactive nanofibrous scaffold (composed of collagen and polycaprolactone and bioactive glass nanoparticles, CPB) for enhancing wound healing. Under the stimulation of CPB nanofibrous system, the viability and angiogenic ability of EPCs were significantly enhanced through the activation of Hif-1α/VEGF/SDF-1α signaling. In vivo, CPB/EPC constructs significantly enhanced the formation of high-density blood vessels by greatly upregulating the expressions of Hif-1α, VEGF, and SDF-1α. Moreover, owing to the increased local delivery of cells and fast neovascularization within the wound site, cell proliferative activity, granulation tissue formation, and collagen synthesis and deposition were greatly promoted by CPB/EPC constructs resulting in rapid re-epithelialization and regeneration of skin appendages. As a result, the synergistic enhancement of wound healing was observed from CPB/EPC constructs, which suggests the highly efficient delivery of EPCs. CPB/EPC constructs may become highly competitive cell-based therapeutic products for efficient impaired wound healing application. This study may also provide a novel strategy to develop bioactive cell therapy constructs for angiogenesis-related regenerative medicine. This paper reported a highly efficient local delivery of EPCs using bioactive glass-based CPB nanofibrous scaffold for enhancing angiogenesis and wound regeneration. In vitro study showed that CPB can promote the proliferation, migration, and tube formation of EPCs through upregulation of the Hif-1α/VEGF/SDF-1α signaling pathway, indicating that the bioactivity and angiogenic ability of

CIRCULATING MICROPARTICLES IN PATIENTS WITH ANTIPHOSPHOLIPID ANTIBODIES: CHARACTERIZATION AND ASSOCIATIONS

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Chaturvedi, Shruti; Cockrell, Erin; Espinola, Ricardo; Hsi, Linda; Fulton, Stacey; Khan, Mohammad; Li, Liang; Fonseca, Fabio; Kundu, Suman; McCrae, Keith R.

2014-01-01

The antiphospholipid syndrome is characterized by venous or arterial thrombosis and/or recurrent fetal loss in the presence of circulating antiphospholipid antibodies. These antibodies cause activation of endothelial and other cell types leading to the release of microparticles with procoagulant and pro-inflammatory properties. The aims of this study were to characterize the levels of endothelial cell, monocyte, platelet derived, and tissue factor-bearing microparticles in patients with antiphospholipid antibodies, to determine the association of circulating microparticles with anticardiolipin and anti-β2-glycoprotein antibodies, and to define the cellular origin of microparticles that express tissue factor. Microparticle content within citrated blood from 47 patients with antiphospholipid antibodies and 144 healthy controls was analyzed within 2 hours of venipuncture. Levels of Annexin-V, CD105 and CD144 (endothelial derived), CD41 (platelet derived) and tissue factor positive microparticles were significantly higher in patients than controls. Though levels of CD14 (monocyte-derived) microparticles in patient plasma were not significantly increased, increased levels of CD14 and tissue factor positive microparticles were observed in patients. Levels of microparticles that stained for CD105 and CD144 showed a positive correlation with IgG (R = 0.60, p=0.006) and IgM anti-beta2-glycoprotein I antibodies (R=0.58, p=0.006). The elevation of endothelial and platelet derived microparticles in patients with APS and their correlation with anti-β2-glycoprotein I antibodies suggests a chronic state of vascular cell activation in these individuals and an important role for β2-glycoprotein I in development of the pro-thrombotic state associated with antiphospholipid antibodies. PMID:25467081

Mesenchymal progenitor cells for the osteogenic lineage.

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Ono, Noriaki; Kronenberg, Henry M

2015-09-01

Mesenchymal progenitors of the osteogenic lineage provide the flexibility for bone to grow, maintain its function and homeostasis. Traditionally, colony-forming-unit fibroblasts (CFU-Fs) have been regarded as surrogates for mesenchymal progenitors; however, this definition cannot address the function of these progenitors in their native setting. Transgenic murine models including lineage-tracing technologies based on the cre-lox system have proven to be useful in delineating mesenchymal progenitors in their native environment. Although heterogeneity of cell populations of interest marked by a promoter-based approach complicates overall interpretation, an emerging complexity of mesenchymal progenitors has been revealed. Current literatures suggest two distinct types of bone progenitor cells; growth-associated mesenchymal progenitors contribute to explosive growth of bone in early life, whereas bone marrow mesenchymal progenitors contribute to the much slower remodeling process and response to injury that occurs mainly in adulthood. More detailed relationships of these progenitors need to be studied through further experimentation.

Transcytosis Involvement in Transport System and Endothelial Permeability of Vascular Leakage during Dengue Virus Infection

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Chanettee Chanthick

2018-02-01

Full Text Available The major role of endothelial cells is to maintain homeostasis of vascular permeability and to preserve the integrity of vascular vessels to prevent fluid leakage. Properly functioning endothelial cells promote physiological balance and stability for blood circulation and fluid components. A monolayer of endothelial cells has the ability to regulate paracellular and transcellular pathways for transport proteins, solutes, and fluid. In addition to the paracellular pathway, the transcellular pathway is another route of endothelial permeability that mediates vascular permeability under physiologic conditions. The transcellular pathway was found to be associated with an assortment of disease pathogeneses. The clinical manifestation of severe dengue infection in humans is vascular leakage and hemorrhagic diatheses. This review explores and describes the transcellular pathway, which is an alternate route of vascular permeability during dengue infection that corresponds with the pathologic finding of intact tight junction. This pathway may be the route of albumin transport that causes endothelial dysfunction during dengue virus infection.

Endothelial dysfunction in rectal cancer patients chronically exposed to ionizing radiation

Energy Technology Data Exchange (ETDEWEB)

Rakhypbekov, Tolebay; Pak, Laura; Chaizhunusova, Nailya; Manambayeva, Zukhra; Tokanova, Sholpan; Madiyeva, Madina [Semey State Medical University, Semey (Kazakhstan); Inoue, Ken [Kochi University, Health Service Center, Kochi (Japan); Kawano, Noriyuki; Hoshi, Masaharu [Hiroshima University, Hiroshima (Japan); Takeichi, Nobuo [Takeichi Clinic, Hiroshima (Japan); Noso, Yoshihiro [Shimane University, Department of General Surgery, Faculty of Medicine, Shimane (Japan); Khozhayev, Arman; Molgazhdarov, Maulen [The Kazakh National Medical University of S.D.Asfendiyarov, Department of Oncology, Almaty (Kazakhstan); Olzhaev, Sayakhat [Almaty Regional Oncologic Hospital, Department of Oncology, Almaty (Kazakhstan)

2017-08-15

We sought to identify the features of endothelial function in rectal cancer patients who were exposed to chronic ionizing radiation from a nuclear test site in Kazakhstan. We examined 146 individuals, 76 of whom were rectal cancer patients. The existence of a complex of disturbances of the endothelium and hemostasis systems in patients vs non-patients was revealed. Endothelial dysfunction was expressed as an increase of nitric oxide (NO) production along with decreases in vasodilatation function, and increased levels of von Willebrand factor in blood, along with an increase in the number of circulating endotheliocytes. Significant correlations between indicators of endothelial function and vascular-platelet hemostasis were observed. These changes and their interrelations were expressed more strongly in the patients who lived in the contaminated area around the nuclear test site. Such patients could have an increased risk of thrombosis and other complications after the treatment of a malignant neoplasm. (orig.)

Extracellular matrix inspired surface functionalization with heparin, fibronectin and VEGF provides an anticoagulant and endothelialization supporting microenvironment

International Nuclear Information System (INIS)

Wang, Xue; Liu, Tao; Chen, Yuan; Zhang, Kun; Maitz, Manfred F.; Pan, Changjiang; Chen, Junying; Huang, Nan

2014-01-01

Highlights: • Surface modification with fibronectin, heparin and VEGF could selectively anticoagulant and promote endothelialization. • The bioactivity of biomolecules was more efficiently maintained via specific intermolecular interaction. • Poly-l-lysine interlayer was more feasible and the degradation product had no harm to human body. - Abstract: The biocompatibility of currently used coronary artery stent is still far from perfect, which closely related to insufficient endothelialization and thrombus formation. In this study, heparin, fibronectin and VEGF were immobilized on Ti surface to construct a multifunctional microenvironment with favorable properties to inhibit thrombosis formation and promote endothelialization simultaneously. The microenvironment on Ti surface was characterized in detail and demonstrated that the Hep/Fn/VEGF biofunctional coating was constructed successfully on Ti surface. The influence of surface properties such as chemical composition, roughness, hydrophilicity, and binding density of biomolecules on the performances of hemocompatibility and cytocompatibility was evaluated and discussed. Modified surface significantly enhanced the AT III binding density and prolonged the clotting time. In vitro platelet adhesion and activation assays further proved that the modified surface presented favorable anti-coagulant property. In addition, the proliferation of endothelial progenitor cells (EPCs) and endothelial cells (ECs) on the Hep/Fn/VEGF biofunctional coating was significantly promoted. In conclusion, the Hep/Fn/VEGF biofunctional coating was successfully constructed with desirable anticoagulant and endothelialization supporting properties. This work may provide a promising approach for biofunctional surface modification of coronary artery stent to acquire a desired multifunctional microenvironment

Protective effects on vascular endothelial cell in N'-nitro-L-arginine (L-NNA)-induced hypertensive rats from the combination of effective components of Uncaria rhynchophylla and Semen Raphani.

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Li, Yunlun; Yang, Wenqing; Zhu, Qingjun; Yang, Jinguo; Wang, Zhen

2015-08-01

Endothelial dysfunction is closely associated with hypertension. Protection of vascular endothelial cell is the key to prevention and treatment of hypertension. Uncaria rhynchophylla total alkaloids and Semen Raphani soluble alkaloid, isolated from traditional Chinese medicine Uncaria rbyncbopbylla and Semen Raphani respectively, exhibit properties of anti-hypertension and protection of blood vessels. In the present study, we observed the protective effect of the combined use of Uncaria rhynchophylla total alkaloids and Semen Raphani soluble alkaloid to the vascular endothelial cell in N'-nitro-L-arginine-induced hypertensive rats and investigate the preliminary mechanism. Blood pressure was detected by non-invasive rats tail method to observe the anti-hypertension effect of drugs. Scanning electron microscopy was used to observe the integrity or shedding state of vascular endothelial cell. The amount of circulating endothelial cells and CD54 and CD62P expression on circulating endothelial cells were tested to evaluate the endothelium function. In this study, we found that the Uncaria rhynchophylla total alkaloids and Semen Raphani soluble alkaloid compatibility can effectively lower the blood pressure, improve the structural integrity of vascular endothelium, and significantly reduce the number of circulating endothelial cells. Furthermore, the mean fluorescence intensity of CD54 and CD62P expressed showed decrease after the intervention of Uncaria rhynchophylla total alkaloids and Semen Raphani soluble alkaloid compatibility. In conclusion, the combination of effective components of the Uncaria rhynchophylla total alkaloids and Semen Raphani soluble alkaloid demonstrated good antihypertension effect and vascular endothelium protective effect. The preliminary mechanism of the protective effect may attribute to relieve the overall low-grade inflammation.

Effects of a 12-week alpine skiing intervention on endothelial progenitor cells, peripheral arterial tone and endothelial biomarkers in the elderly

DEFF Research Database (Denmark)

Niederseer, David; Steidle-Kloc, Eva; Mayr, Matthias

2016-01-01

: +0.18±0.76) and CG (-0.39±0.85; p=0.045), as did homocysteine (IG: -1.3±1.3μmol/l; CG: -0.4±1.4μmol/l; p=0.037) while other endothelial biomarkers remained essentially unchanged. CONCLUSIONS: This study shows that skiing induces several beneficial effects on markers of atherogenesis including EPCs......, peripheral arterial tone and homocysteine. Our findings suggest that recreational alpine skiing may serve as a further mode of preventive exercise training, which might result in improved compliance with current recommendations....

The interaction between circulating complement proteins and cutaneous microvascular endothelial cells in the development of childhood Henoch-Schonlein Purpura.

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Yao-Hsu Yang

Full Text Available In addition to IgA, the deposition of complement (C3 in dermal vessels is commonly found in Henoch-Schönlein purpura (HSP. The aim of this study is to elucidate the role of circulating complement proteins in the pathogenesis of childhood HSP.Plasma levels of C3a, C4a, C5a, and Bb in 30 HSP patients and 30 healthy controls were detected by enzyme-linked immunosorbent assay (ELISA. The expression of C3a receptor (C3aR, C5a receptor (CD88, E-selectin, intercellular adhesion molecule 1 (ICAM-1, C3, C5, interleukin (IL-8, monocyte chemotactic protein (MCP-1, and RANTES by human dermal microvascular endothelial cells (HMVEC-d was evaluated either by flow cytometry or by ELISA.At the acute stage, HSP patients had higher plasma levels of C3a (359.5 ± 115.3 vs. 183.3 ± 94.1 ng/ml, p < 0.0001, C5a (181.4 ± 86.1 vs. 33.7 ± 26.3 ng/ml, p < 0.0001, and Bb (3.7 ± 2.6 vs. 1.0 ± 0.6 μg/ml, p < 0.0001, but not C4a than healthy controls. Although HSP patient-derived acute phase plasma did not alter the presentation of C3aR and CD88 on HMVEC-d, it enhanced the production of endothelial C3 and C5. Moreover, C5a was shown in vitro to up-regulate the expression of IL-8, MCP-1, E-selectin, and ICAM-1 by HMVEC-d with a dose-dependent manner.In HSP, the activation of the complement system in part through the alternative pathway may have resulted in increased plasma levels of C3a and C5a, which, especially C5a, may play a role in the disease pathogenesis by activating endothelium of cutaneous small vessels.

In vitro cultured progenitors and precursors of cardiac cell lineages from human normal and post-ischemic hearts

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F Di Meglio

2009-08-01

Full Text Available The demonstration of the presence of dividing primitive cells in damaged hearts has sparked increased interest about myocardium regenerative processes. We examined the rate and the differentiation of in vitro cultured resident cardiac primitive cells obtained from pathological and normal human hearts in order to evaluate the activation of progenitors and precursors of cardiac cell lineages in post-ischemic human hearts. The precursors and progenitors of cardiomyocyte, smooth muscle and endothelial lineage were identified by immunocytochemistry and the expression of characteristic markers was studied by western blot and RT-PCR. The amount of proteins characteristic for cardiac cells (a-SA and MHC, VEGFR-2 and FVIII, SMA for the precursors of cardiomyocytes, endothelial and smooth muscle cells, respectively inclines toward an increase in both a-SA and MHC. The increased levels of FVIII and VEGFR2 are statistically significant, suggesting an important re-activation of neoangiogenesis. At the same time, the augmented expression of mRNA for Nkx 2.5, the trascriptional factor for cardiomyocyte differentiation, confirms the persistence of differentiative processes in terminally injured hearts. Our study would appear to confirm the activation of human heart regeneration potential in pathological conditions and the ability of its primitive cells to maintain their proliferative capability in vitro. The cardiac cell isolation method we used could be useful in the future for studying modifications to the microenvironment that positively influence cardiac primitive cell differentiation or inhibit, or retard, the pathological remodeling and functional degradation of the heart.

Transplantation of autologous endothelial progenitor cells in porous PLGA scaffolds create a microenvironment for the regeneration of hyaline cartilage in rabbits.

Science.gov (United States)

Chang, N-J; Lam, C-F; Lin, C-C; Chen, W-L; Li, C-F; Lin, Y-T; Yeh, M-L

2013-10-01

Repairing articular cartilage is clinically challenging. We investigated a simple, effective and clinically feasible cell-based therapeutic approach using a poly(lactide-co-glycolide) (PLGA) scaffold seeded with autologous endothelial progenitor cells (EPC) to repair a full-thickness osteochondral defect in rabbits using a one-step surgery. EPC obtained by purifying a small amount of peripheral blood from rabbits were seeded into a highly porous, biocompatible PLGA scaffold, namely, EPC-PLGA, and implanted into the osteochondral defect in the medial femoral condyle. Twenty two rabbits were randomized into one of three groups: the empty defect group (ED), the PLGA-only group or the EPC-PLGA group. The defect sites were evaluated 4 and 12 weeks after implantation. At the end of testing, only the EPC-PLGA group showed the development of new cartilage tissue with a smooth, transparent and integrated articular surface. Moreover, histological analysis showed obvious differences in cartilage regeneration. At week 4, the EPC-PLGA group showed considerably higher TGF-β2 and TGF-β3 expression, a greater amount of synthesized glycosaminoglycan (GAG) content, and a higher degree of osteochondral angiogenesis in repaired tissues. At week 12, the EPC-PLGA group showed enhanced hyaline cartilage regeneration with a normal columnar chondrocyte arrangement, higher SOX9 expression, and greater GAG and collagen type II (COLII) content. Moreover, the EPC-PLGA group showed organized osteochondral integration, the formation of vessel-rich tubercular bone and significantly higher bone volume per tissue volume and trabecular thickness (Tb.Th). The present EPC-PLGA cell delivery system generates a suitable in situ microenvironment for osteochondral regeneration without the supplement of exogenous growth factors. Copyright © 2013 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Cancer cells remodel themselves and vasculature to overcome the endothelial barrier.

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Shenoy, Anitha K; Lu, Jianrong

2016-10-01

Metastasis refers to the spread of cancer cells from a primary tumor to distant organs mostly via the bloodstream. During the metastatic process, cancer cells invade blood vessels to enter circulation, and later exit the vasculature at a distant site. Endothelial cells that line blood vessels normally serve as a barrier to the movement of cells into or out of the blood. It is thus critical to understand how metastatic cancer cells overcome the endothelial barrier. Epithelial cancer cells acquire increased motility and invasiveness through epithelial-to-mesenchymal transition (EMT), which enables them to move toward vasculature. Cancer cells also express a variety of adhesion molecules that allow them to attach to vascular endothelium. Finally, cancer cells secrete or induce growth factors and cytokines to actively prompt vascular hyperpermeability that compromises endothelial barrier function and facilitates transmigration of cancer cells through the vascular wall. Elucidation of the mechanisms underlying metastatic dissemination may help develop new anti-metastasis therapeutics. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Vascular Endothelial Growth Factor Receptor 3 Controls Neural Stem Cell Activation in Mice and Humans

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Jinah Han

2015-02-01

Full Text Available Neural stem cells (NSCs continuously produce new neurons within the adult mammalian hippocampus. NSCs are typically quiescent but activated to self-renew or differentiate into neural progenitor cells. The molecular mechanisms of NSC activation remain poorly understood. Here, we show that adult hippocampal NSCs express vascular endothelial growth factor receptor (VEGFR 3 and its ligand VEGF-C, which activates quiescent NSCs to enter the cell cycle and generate progenitor cells. Hippocampal NSC activation and neurogenesis are impaired by conditional deletion of Vegfr3 in NSCs. Functionally, this is associated with compromised NSC activation in response to VEGF-C and physical activity. In NSCs derived from human embryonic stem cells (hESCs, VEGF-C/VEGFR3 mediates intracellular activation of AKT and ERK pathways that control cell fate and proliferation. These findings identify VEGF-C/VEGFR3 signaling as a specific regulator of NSC activation and neurogenesis in mammals.

Pravastatin Protects Against Avascular Necrosis of Femoral Head via Autophagy.

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Liao, Yun; Zhang, Ping; Yuan, Bo; Li, Ling; Bao, Shisan

2018-01-01

Autophagy serves as a stress response and may contribute to the pathogenesis of avascular necrosis of the femoral head induced by steroids. Statins promote angiogenesis and ameliorate endothelial functions through apoptosis inhibition and necrosis of endothelial progenitor cells, however the process used by statins to modulate autophagy in avascular necrosis of the femoral head remains unclear. This manuscript determines whether pravastatin protects against dexamethasone-induced avascular necrosis of the femoral head by activating endothelial progenitor cell autophagy. Pravastatin was observed to enhance the autophagy activity in endothelial progenitor cells, specifically by upregulating LC3-II/Beclin-1 (autophagy related proteins), and autophagosome formation in vivo and in vitro . An autophagy inhibitor, 3-MA, reduced pravastatin protection in endothelial progenitor cells exposed to dexamethasone by attenuating pravastatin-induced autophagy. Adenosine monophosphate-activated protein kinase (AMPK) is a key autophagy regulator by sensing cellular energy changes, and indirectly suppressing activation of the mammalian target of rapamycin (mTOR). We found that phosphorylation of AMPK was upregulated however phosphorylation of mTOR was downregulated in pravastatin-treated endothelial progenitor cells, which was attenuated by AMPK inhibitor compound C. Furthermore, liver kinase B1 (a phosphorylase of AMPK) knockdown eliminated pravastatin regulated autophagy protein LC3-II in endothelial progenitor cells in vitro . We therefore demonstrated pravastatin rescued endothelial progenitor cells from dexamethasone-induced autophagy dysfunction through the AMPK-mTOR signaling pathway in a liver kinase B1-dependent manner. Our results provide useful information for the development of novel therapeutics for management of glucocorticoids-induced avascular necrosis of the femoral head.

Heparin defends against the toxicity of circulating histones in sepsis.

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Wang, Feifei; Zhang, Naipu; Li, Biru; Liu, Lanbo; Ding, Lei; Wang, Ying; Zhu, Yimin; Mo, Xi; Cao, Qing

2015-06-01

Although circulating histones were demonstrated as major mediators of death in septic mice models, their roles in septic patients are not clarified. The present study sought to evaluate the clinical relevance of the circulating histone levels in septic children, and the antagonizing effects of heparin on circulating histones. Histone levels in the plasma of septic children were significantly higher than healthy controls, and positively correlated with disease severity. Histone treatment could activate NF-κB pathway of the endothelial cells and induce the secretion of large amount of cytokines that further amplify inflammation, subsequently leading to organ damage. Co-injection of low dose heparin with lethal dose histones could protect mouse from organ damage and death by antagonizing circulating histones, and similar effects were also observed in other septic models. Collectively, these findings indicated that circulating histones might serve as key factors in the pathogenesis of sepsis and their levels in plasma might be a marker for disease progression and prognosis. Furthermore, low dose heparin might be an effective therapy to hamper sepsis progression and reduce the mortality.

Mobilization of endothelial precursor cells: systemic vascular response to musculoskeletal trauma.

LENUS (Irish Health Repository)

Laing, A J

2012-02-03

Postnatal vasculogenesis, the process by which vascular committed bone marrow stem cells or endothelial precursor cells (EPC) migrate, differentiate, and incorporate into the nacent endothelium contributing to physiological and pathological neovascularization, has stimulated much interest. Its contribution to tumor nonvascularization, wound healing, and revascularization associated with skeletal and cardiac muscles ischaemia is established. We evaluated the mobilization of EPCs in response to musculoskeletal trauma. Blood from patients (n = 15) following AO type 42a1 closed diaphyseal tibial fractures was analyzed for CD34 and AC133 cell surface marker expression. Immunomagnetically enriched CD34+ mononuclear cell (MNC(CD34+)) populations were cultured and examined for phenotypic and functional vascular endothelial differentiation. Circulating MNC(CD34+) levels increased sevenfold by day 3 postinjury. Circulating MNC(AC133+) increased 2.5-fold. Enriched MNC(CD34+) populations from day 3 samples in culture exhibited cell cluster formation with sprouting spindles. These cells bound UEA-1 and incorporated fluorescent DiI-Ac-LDL intracellularily. Our findings suggest a systemic provascular response is initiated in response to musculoskeletal trauma. Its therapeutic manipulation may have implications for the potential enhancement of fracture healing.

In Vitro Endothelial Cell Proliferation Assay Reveals Distinct Levels of Proangiogenic Cytokines Characterizing Sera of Healthy Subjects and of Patients with Heart Failure

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Rebecca Voltan

2014-01-01

Full Text Available Although myocardial angiogenesis is thought to play an important role in heart failure (HF, the involvement of circulating proinflammatory and proangiogenic cytokines in the pathogenesis and/or prognosis of HF has not been deeply investigated. By using a highly standardized proliferation assay with human endothelial cells, we first demonstrated that sera from older (mean age 52±7.6 years; n=46 healthy donors promoted endothelial cell proliferation to a significantly higher extent compared to sera obtained from younger healthy donors (mean age 29±8.6 years; n=20. The promotion of endothelial cell proliferation was accompanied by high serum levels of several proangiogenic cytokines. When we assessed endothelial cell proliferation in response to HF patients’ sera, we observed that a subset of sera (n=11 promoted cell proliferation to a significantly lesser extent compared to the majority of sera (n=18. Also, in this case, the difference between the patient groups in the ability to induce endothelial cell proliferation correlated to significant (P<0.05 differences in serum proangiogenic cytokine levels. Unexpectedly, HF patients associated to the highest endothelial proliferation index showed the worst prognosis as evaluated in terms of subsequent cardiovascular events in the follow-up, suggesting that high levels of circulating proangiogenic cytokines might be related to a worse prognosis.

Tanshinone II A Attenuates TNF-α-Induced Expression of VCAM-1 and ICAM-1 in Endothelial Progenitor Cells by Blocking Activation of NF-κB

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Jin-Xiu Yang

2016-11-01

Full Text Available Background/Aims: Tanshinone IIA (Tan IIA is effective in the treatment of inflammation and atherosclerosis. The adhesion of inflammatory cells to vascular endothelium plays important role in atherogenic processes. This study examined the effects of Tan IIA on expression of adhesion molecules in tumor necrosis factor-α (TNF-α-induced endothelial progenitor cells (EPCs. Methods: EPCs were pretreated with Tan IIA and stimulated with TNF-α. Mononuclear cell (MNC adhesion assay was performed to assess the effects of Tan IIA on TNF-α-induced MNC adhesion. Expression of vascular cell adhesion molecule-1 (VCAM-1/intracellular adhesion molecule-1 (ICAM-1 and activation of Nuclear factor κB (NF-κB signaling pathway were measured. Results: The results showed that the adhesion of MNCs to TNF-α-induced EPCs and expression of VCAM-1/ICAM-1 in EPCs were promoted by TNF-α, which were reduced by Tan IIA. TNF-α increased the amount of phosphorylation of NF-κB, IκB-α and IKKα/β in cytosolic fractions and NF-κB p65 in nucleus, while Tan IIA reduced its amount. Conclusion: This study demonstrated a novel mechanism for the anti-inflammatory/anti-atherosclerotic activity of Tan IIA, which may involve down-regulation of VCAM-1 and ICAM-1 through partial blockage of TNF-α-induced NF-κB activation and IκB-α phosphorylation by the inhibition of IKKα/β pathway in EPCs.

Lysophosphatidic acid stimulates thrombomodulin lectin-like domain shedding in human endothelial cells

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Wu Hualin; Lin ChiIou; Huang Yuanli; Chen, Pin-Shern; Kuo, Cheng-Hsiang; Chen, Mei-Shing; Wu, G.C.-C.; Shi, G.-Y.; Yang, H.-Y.; Lee Hsinyu

2008-01-01

Thrombomodulin (TM) is an anticoagulant glycoprotein highly expressed on endothelial cell surfaces. Increased levels of soluble TM in circulation have been widely accepted as an indicator of endothelial damage or dysfunction. Previous studies indicated that various proinflammatory factors stimulate TM shedding in various cell types such as smooth muscle cells and epithelial cells. Lysophosphatidic acid (LPA) is a bioactive lipid mediator present in biological fluids during endothelial damage or injury. In the present study, we first observed that LPA triggered TM shedding in human umbilical vein endothelial cells (HUVECs). By Cyflow analysis, we showed that the LPA-induced accessibility of antibodies to the endothelial growth factor (EGF)-like domain of TM is independent of matrix metalloproteinases (MMPs), while LPA-induced TM lectin-like domain shedding is MMP-dependent. Furthermore, a stable cell line expressing TM without its lectin-like domain exhibited a higher cell proliferation rate than a stable cell line expressing full-length TM. These results imply that LPA induces TM lectin-like domain shedding, which might contribute to the exposure of its EGF-like domain for EGF receptor (EGFR) binding, thereby stimulating subsequent cell proliferation. Based on our findings, we propose a novel mechanism for the exposure of TM EGF-like domain, which possibly mediates LPA-induced EGFR transactivation

Endotoxin-induced monocytic microparticles have contrasting effects on endothelial inflammatory responses.

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Beryl Wen