Effects of adrenomedullin on the cell numbers and apoptosis of endothelial progenitor cells

Purpose: To investigate the effect of adrenomedullin on the cell numbers and apoptosis of endothelial progenitor cells (EPCs). Methods: Mononuclear cells were isolated from peripheral blood by Ficoll density gradient centrifugation. The cells were stimulated with adrenomedullin, before and after the treatment of adrenomedullin-receptor antagonist, adrenomedullin 22-52, or a PI3K inhibitor LY294002. Results: Adrenomedullin dose-dependently increased the number of EPCs (P < 0.05). Adrenomedullin also significantly decreased apoptosis rate of EPCs in a concentration-dependent manner (P < 0.05). In the isolated human mononuclear cells pretreated with adrenomedullin 22-52 or LY294002, adrenomedullin failed to increase the number of EPCs or to reduce the level of apoptosis. Conclusions: Adrenomedullin increases the number of EPCs and decreases their apoptosis. These actions are likely mediated by PI3K signaling pathways. The clinical importance of these favourable effects on EPCs remains to be determined.

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Protective Effect of Silymarin against Rapamycin-induced Apoptosis and Proliferation Inhibition in Endothelial Progenitor Cells

Natural Product Communications ◽

10.1177/1934578x1501000211 ◽

2015 ◽

Vol 10 (2) ◽

pp. 1934578X1501000 ◽

Cited By ~ 2

Author(s):

Peng Zhang ◽

Guohua Han ◽

Pei Gao ◽

Kun Qiao ◽

Yusheng Ren ◽

...

Keyword(s):

Progenitor Cells ◽

Endothelial Progenitor Cells ◽

Mononuclear Cells ◽

Control Group ◽

Dependent Manner ◽

Endothelial Progenitor ◽

Concentration Dependent Manner ◽

Inhibition Of Proliferation ◽

And Migration ◽

Proliferation And Migration

For this study, peripheral blood samples were collected from human volunteers. Mononuclear cells (MNC) were separated by density centrifugation and were induced to differentiate into endothelial progenitor cells (EPCs) in vitro. Different concentrations of rapamycin and silymarin were introduced to the EPCs over 24 hours and then EPCs were analyzed for proliferation, migration, apoptosis and angiogenesis. Compared with the control group, rapamycin (1, 10, 100 ng/mL) inhibited the proliferation and migration of EPCs in a concentration dependent manner ( P<0.05). Silymarin (50, 100 μg/mL) enhanced the proliferation and migration of EPCs and inhibited apoptosis in a concentration dependent manner ( P<0.05). By adding rapamycin (1 ng/mL) and silymarin (25, 50, 100 μg/mL) over 24 hours, silymarin inhibited the pro-apoptotic effect of rapamycin on EPCs, and reversed the inhibition of proliferation, migration and angiogenesis of EPCs by rapamycin ( P<0.05).

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Exposure of Human Endothelial Progenitors to Sevoflurane Improves Their Survival Abilities

Revista Romana de Medicina de Laborator ◽

10.1515/rrlm-2016-0022 ◽

2016 ◽

Vol 24 (2) ◽

pp. 177-186

Author(s):

Adelina Munteanu ◽

Marilena Gilca ◽

Gheorghita Isvoranu ◽

Mihaela Surcel ◽

Laura Ceafalan ◽

...

Keyword(s):

Progenitor Cells ◽

Endothelial Progenitor Cells ◽

Cell Biology ◽

Mononuclear Cells ◽

Gradient Centrifugation ◽

Human Umbilical Cord Blood ◽

Tetrazolium Salt ◽

Human Umbilical Cord ◽

Endothelial Progenitor ◽

Post Exposure

Abstract Endothelial progenitor cells (EPCs) have prominent roles in vessel and tissue repair; however, their regenerative efficacy is diminished due to the poor survival in the hostile microenvironment of the injured organs. Recent data suggest a promising potential of volatile anesthetics for improving stem cell biology. Thus, we hypothesized that exposure to sevoflurane could stimulate growth and viability of cultured EPCs. Total mononuclear cells were isolated from human umbilical cord blood by gradient centrifugation. After five days in culture, the cells were exposed for one or two hours to sevoflurane 2% or 4% in air/5% CO2, or only to air/5% CO2 (sham control) in a sealed modular chamber. 24 or 48 hours post-exposure, viability, proliferation and apoptosis were assessed using lactate dehydrogenase (LDH) leakage assay, a methyl tetrazolium salt (MTS) assay and FITC-annexin V/ propidium iodide (PI) staining, respectively. LDH leakage was discretely lowered, whereas the levels of formazan were significantly increased (p < 0.05 for 1 h incubation with 4% sevoflurane at 24 hrs post-exposure, and with 2% sevoflurane at 48 h post-exposure) in the preconditioned cultures, proving no cytotoxic effects and increased proliferation in treated cells versus control samples. Early (p < 0.05) and late apoptosis (p < 0.05 only for 2% sevoflurane) were diminished following the procedure. Thus, the commonly used sevoflurane anesthetic has protective effects on viability and proliferation of human early endothelial progenitor cells in vitro, suggesting a promising potential of anesthetic preconditioning for improving the regeneration of ischemic tissues.

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Study on MR Imaging of Endothelial Progenitor Cells Labeled with the Complex of Super Paramagnetic Iron Oxide and Transfection

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.683.885 ◽

2013 ◽

Vol 683 ◽

pp. 885-888

Author(s):

Na Chang ◽

Jun Zhang ◽

Jun Shi Zhang

Keyword(s):

Iron Oxide ◽

Mr Imaging ◽

Progenitor Cells ◽

Endothelial Progenitor Cells ◽

Mononuclear Cells ◽

Gradient Centrifugation ◽

Superparamagnetic Iron Oxide ◽

Effective Rate ◽

Endothelial Progenitor ◽

Ficoll Density Gradient Centrifugation

To explore the characteristics of magnetic resonance（MR）imaging of the rat endothelial progenitor cells（EPCs）labeled with superparamagnetic iron oxide（SPIO）. Total mononuclear cells (MNCs) were isolated from SD rat peripheral blood by ficoll density gradient centrifugation, and then the cells were plated on fibronectin-coated culture dishes. Attached cells were collected after 7 days cultured. EPCs were indentified by the laser confocal microscope and were counted in the inverted fluorescence microscope. EPCs were incubated with Fe2O3-arginine for 24 h, and the cells underwent MR imaging with three sequences (T1 WI, T2 WI, T2*WI). The results showed that the effective rate of labeled EPCs was 96%, and the survival rate of cells was 95%. The signal intensity on MRI was significantly decreased in labeled EPCs compared with unlabeled cells. EPCs labeled with SPIO can be sensitively displayed by the MR imaging.

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Endothelial progenitor cells in pregnancy

Reproduction ◽

10.1530/rep-06-0219 ◽

2007 ◽

Vol 133 (1) ◽

pp. 1-9 ◽

Cited By ~ 32

Author(s):

Amy O Robb ◽

Nicholas L Mills ◽

David E Newby ◽

Fiona C Denison

Keyword(s):

Endothelial Dysfunction ◽

Progenitor Cells ◽

Endothelial Progenitor Cells ◽

Progenitor Cell ◽

Mononuclear Cells ◽

Vascular System ◽

Specific Reference ◽

Vascular Repair ◽

Endothelial Progenitor ◽

Cell Numbers

The discovery of endothelial progenitor cells has generated considerable interest in the field of vascular biology. These cells arise from a population of circulating mononuclear cells and have the capacity to form new blood vessels and contribute to vascular repair. Circulating endothelial progenitor cell numbers are reduced in patients with cardiovascular risk factors and in the presence of endothelial dysfunction, but are increased in response to ischaemia, oestrogens and drug therapy. They have been studied in pathologies from cardiovascular and renal disease to rheumatoid arthritis and pre-eclampsia. Pregnancy is a challenge to the maternal vascular system, requiring systemic adaptation and pronounced local changes in the uterus. Diseases of pregnancy such as pre-eclampsia and gestational diabetes increase the risk of pregnancy complications and are associated with endothelial dysfunction. We propose that endothelial progenitor cells have an important role in the regulation and maintenance of the vasculature during pregnancy. This review summarises our current understanding of endothelial progenitor cells, with specific reference to their role in angiogenesis and human pregnancy.

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

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2013/943187 ◽

2013 ◽

Vol 2013 ◽

pp. 1-10 ◽

Cited By ~ 17

Author(s):

Ching-Hu Chung ◽

Chien-Hsin Chang ◽

Shiou-Sheng Chen ◽

Hsueh-Hsiao Wang ◽

Juei-Yu Yen ◽

...

Keyword(s):

Progenitor Cells ◽

Endothelial Progenitor Cells ◽

Angiogenesis Inhibitor ◽

Dependent Manner ◽

Metastatic Progression ◽

Endothelial Progenitor ◽

Concentration Dependent Manner ◽

Antiangiogenic Effect ◽

Angiogenic Switch

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 assayin 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 bothin vitroandin vivoby targeting the translational machinery. Butein is a promising angiogenesis inhibitor with the potential for treatment of cancer and other angiogenesis-related diseases.

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Presence of endothelial progenitor cells, distinct from mature endothelial cells, within human CD146+ blood cells

Thrombosis and Haemostasis ◽

10.1160/th05-07-0499 ◽

2005 ◽

Vol 94 (12) ◽

pp. 1270-1279 ◽

Cited By ~ 82

Author(s):

Bruno Delorme ◽

Agnès Basire ◽

Carla Gentile ◽

Florence Sabatier ◽

Frédéric Monsonis ◽

...

Keyword(s):

Endothelial Cells ◽

Progenitor Cells ◽

Endothelial Progenitor Cells ◽

Network Formation ◽

Mononuclear Cells ◽

Circulating Endothelial Cells ◽

Endothelial Progenitor ◽

Color Flow ◽

Immunodeficient Mice ◽

Circulating Cells

SummaryCD146 is an adhesion molecule present on endothelial cells throughout the vascular tree. CD146 is also expressed by circulating endothelial cells (CECs) widely considered to be mature endothelial cells detached from injured vessels. The discovery of circulating endothelial progenitor cells (EPCs) originating from bone marrow prompted us to investigate whether CD146 circulating cells could also contains EPCs. We tested this hypothesis using an approach combining elimination of CECs by an adhesion step, followed by immunomagnetic sorting of remaining CD146+ cells from the non adherent fraction of cord blood mononuclear cells. When cultured under endothelial-promoting conditions, these cells differentiated as late outgrowth endothelial colonies: they grew as a cobblestone monolayer, were uniformly positive for endothelial markers and did not express leukocyte antigens. They highly proliferated and were expanded in long-term culture without alterations of their phenotypic and functional properties (DiI-ac-LDL uptake, wound repair, capillary-like network formation, and TNFα response). Moreover, these cells colonized a Matrigel plug in immunodeficient mice (NOD/SCID). Finally, using 4-color flow cytometry analysis of purified CD34+ cells, we clearly discriminated, CD146+ EPCs (CD146+ CD34+ CD45+ CD133+ or CD117+), and CD146+ CECs (CD146+ CD34+, CD45− CD133− or CD117−), both in cord and adult peripheral blood. The relative proportions of the two CD146+ subsets varied in patients with myocardial infarction as compared to healthy subjects. Our study establishes that, beside CECs, CD146+ circulating cells contain a subpopulation of EPCs with potential use in proangiogenic therapy. In addition, the dual measurement of CD146+ CECs and CD146+ EPCs offers a promising tool for monitoring vascular injury/regeneration processes in clinical situations.

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Interleukin-1β Augments Angiogenic Responses of Murine Endothelial Progenitor Cells in Vitro

Journal of Cerebral Blood Flow & Metabolism ◽

10.1038/jcbfm.2009.17 ◽

2009 ◽

Vol 29 (5) ◽

pp. 933-943 ◽

Cited By ~ 48

Author(s):

Anna Rosell ◽

Ken Arai ◽

Josephine Lok ◽

Tongrong He ◽

Shuzhen Guo ◽

...

Keyword(s):

Progenitor Cells ◽

Endothelial Progenitor Cells ◽

Mononuclear Cells ◽

Therapeutic Angiogenesis ◽

Interleukin 1Β ◽

Endothelial Progenitor ◽

Angiogenic Potential ◽

Diphenyl Tetrazolium Bromide ◽

In Vitro Angiogenesis

Endothelial progenitor cells (EPCs) may provide novel opportunities for therapeutic angiogenesis after ischemic diseases. However, it is unclear how the angiogenic potential of EPCs might be affected by an inflammatory environment. We examine how the potent cytokine interleukin-1β (IL-1β) affects angiovasculogenic responses in EPCs in culture. Mononuclear cells isolated from mouse spleen were plated on fibronectin-coated wells and grown in EGM-2 MV media. Endothelial progenitor cells were phenotyped using multiple markers (UEA-Lectin, ac-LDL, CD133, CD34, vWillebrand Factor, Flk-1) and to identify the IL-1 Receptor-I. We quantified cell and colony counts and performed MTT (3-(4,5-dimethylthiazol-2-yl)2,5-diphenyl-tetrazolium bromide) and Matrigel assays, in vitro, under control and IL-1β (10 ng/mL) conditions. Endothelial progenitor cells exposed to IL-1β increased in the number of cells and colonies compared with untreated cells, without any effect on cell metabolic integrity. Furthermore, IL-1β treatment augmented EPC angiogenic function, significantly increasing the number of vessel-like structures in the Matrigel assay. An early phosphorylation of ERK1/2 occurred after IL-1β stimulation, and this pathway was inhibited if IL-1 Receptor-I was blocked. Our results suggest that IL-1β is a potent stimulator of in vitro angiogenesis through ERK signaling in mouse EPCs. Further studies are warranted to assess how interactions between proinflammatory environments and EPC responses may be leveraged to enhance therapeutic angiogenesis.

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Abstract TP275: “Touch-and-Go”: Touching of Endothelial Cells by Endothelial Progenitor Cells Increases Activation of Pro-survival ERK1/2 Signaling

Stroke ◽

10.1161/str.48.suppl_1.tp275 ◽

2017 ◽

Vol 48 (suppl_1) ◽

Author(s):

Emiri T Mandeville ◽

Su Jing Chen ◽

Kazuhide Hayakawa ◽

Ken Arai ◽

Eng H Lo

Keyword(s):

Endothelial Cells ◽

Rat Brain ◽

Progenitor Cells ◽

Endothelial Progenitor Cells ◽

Short Duration ◽

Intracellular Signaling ◽

Infarct Volume ◽

Dependent Manner ◽

Brain Endothelial Cells ◽

Endothelial Progenitor

Background: Cell-based therapies can potentially promote neurological repair for CNS diseases including stroke. Pre-clinical data showed improved infarct volume and neurological scores following injection of Endothelial progenitor cells (EPCs). However relatively few EPCs were found in infarct areas, and mechanisms by which injected EPCs enhance neovascularization are largely unknown. In this study, we hypothesized that circulating EPCs would positively impact intracellular signaling cascades in rat brain endothelial cells (RBECs) even by short-duration contact due to activation of pro-survival ERK1/2 cascades. Methods: Primary RBECs and EPCs were isolated from rat brain and spleen, respectively. These cells were cultured separately, and 10 days later, cultured EPCs were transferred to plates of cultured RBECs. After 1 or 10 min incubation with cell-culture plate shaking, EPCs were washed from the plates and RBECs were subjected to western blot analysis to assess ERK1/2 phosphorylation. As a negative control for EPCs, we prepared neutrophils from different rats. Results: We confirmed that our RBECs and EPCs were viable in vitro by LDH assay and these cells were positive for their cell-type markers assessed by immunostaining. Ten min incubation of EPCs phosphorylated ERK1/2 in RBECs in an EPC-number-dependent manner, whereas identical conditions of neurtrophil incubation did not. Importantly, only 1 min incubation with EPCs significantly upregulated ERK cascades in RBECs. Remaining EPCs on RBEC surfaces may not contribute to ERK1/2 phosphorylation because very few EPCs were observed after washout. In addition, experiments by the same procedure without RBECs did not show ERK phosphorylation. Conclusion: We demonstrated increased activation of pro-survival ERK1/2 signaling in RBECs following short-duration incubation of EPCs. Results suggest that circulating EPCs may not need to be integrated into existing blood vessels to promote neovascularization. Rather, short-duration interactions between EPCs and RBECs may provide a “Touch-and-Go” stimulus that supports brain endothelial cells to make favorable environments for neovascularization.

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