Bone marrow-derived progenitor cells prevent thrombin-induced increase in lung vascular permeability

Since thrombin activation of endothelial cells (ECs) is well-known to increase endothelial permeability by disassembly of adherens junctions (AJs) and actinomyosin contractility mechanism involving myosin light chain (MLC) phosphorylation, we investigated the effects of bone marrow-derived progenitor cells (BMPCs) on the thrombin-induced endothelial permeability response. We observed that addition of BMPCs to endothelial monolayers at a fixed ratio prevented the thrombin-induced decrease in transendothelial electrical resistance, a measure of AJ integrity, and increased mouse pulmonary microvessel filtration coefficient, a measure of transvascular liquid permeability. The barrier protection was coupled to increased vascular endothelial cadherin expression and increased Cdc42 activity in ECs. Using small interfering RNA (siRNA) to deplete Cdc42 in ECs, we demonstrated a key role of Cdc42 in signaling the BMPC-induced endothelial barrier protection. Endothelial integrity induced by BMPCs was also secondary to inhibition of MLC phosphorylation in ECs. Thus BMPCs interacting with ECs prevent thrombin-induced endothelial hyperpermeability by a mechanism involving AJ barrier annealing, inhibition of MLC phosphorylation, and activation of Cdc42.

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Bone Marrow Derived Mesenchymal Stem Cells Inhibit Inflammation and Preserve Vascular Endothelial Integrity in the Lungs after Hemorrhagic Shock

PLoS ONE ◽

10.1371/journal.pone.0025171 ◽

2011 ◽

Vol 6 (9) ◽

pp. e25171 ◽

Cited By ~ 81

Author(s):

Shibani Pati ◽

Michael H. Gerber ◽

Tyler D. Menge ◽

Kathryn A. Wataha ◽

Yuhai Zhao ◽

...

Keyword(s):

Stem Cells ◽

Bone Marrow ◽

Mesenchymal Stem Cells ◽

Hemorrhagic Shock ◽

Vascular Endothelial ◽

Endothelial Integrity

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Endothelial progenitor cells and hypertension: current concepts and future implications

Clinical Science ◽

10.1042/cs20160587 ◽

2016 ◽

Vol 130 (22) ◽

pp. 2029-2042 ◽

Cited By ~ 14

Author(s):

Shengyuan Luo ◽

Wenhao Xia ◽

Cong Chen ◽

Eric A. Robinson ◽

Jun Tao

Keyword(s):

Progenitor Cells ◽

Endothelial Progenitor Cells ◽

Current Knowledge ◽

Circulatory System ◽

Essential Element ◽

Future Research ◽

Chronic Hypertension ◽

Vascular Endothelial ◽

Endothelial Progenitor ◽

Endothelial Integrity

The discovery of endothelial progenitor cells (EPCs), a group of cells that play important roles in angiogenesis and the maintenance of vascular endothelial integrity, has led to considerable improvements in our understanding of the circulatory system and the regulatory mechanisms of vascular homoeostasis. Despite lingering disputes over where EPCs actually originate and how they facilitate angiogenesis, extensive research in the past decade has brought about significant advancements in this field of research, establishing EPCs as an essential element in the pathogenesis of various diseases. EPC and hypertensive disorders, especially essential hypertension (EH, also known as primary hypertension), represent one of the most appealing branches in this area of research. Chronic hypertension remains a major threat to public health, and the exact pathologic mechanisms of EH have never been fully elucidated. Is there a relationship between EPC and hypertension? If so, what is the nature of such relationship–is it mediated by blood pressure alterations, or other factors that lie in between? How can our current knowledge about EPCs be utilized to advance the prevention and clinical management of hypertension? In this review, we set out to answer these questions by summarizing the current concepts about EPC pathophysiology in the context of hypertension, while attempting to point out directions for future research on this subject.

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TNF-α-induced matrix Fn disruption and decreased endothelial integrity are independent of Fn proteolysis

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.1998.275.1.l126 ◽

1998 ◽

Vol 275 (1) ◽

pp. L126-L138 ◽

Cited By ~ 6

Author(s):

Theresa M. Curtis ◽

Robert F. Rotundo ◽

Peter A. Vincent ◽

Paula J. McKeown-Longo ◽

Thomas M. Saba

Keyword(s):

Extracellular Matrix ◽

Endothelial Permeability ◽

Fragmentation Pattern ◽

Endothelial Monolayers ◽

Tnf Α ◽

The Matrix ◽

Pulmonary Arterial ◽

Permeability Increase ◽

Endothelial Integrity ◽

Protein Permeability

Exposure of confluent pulmonary arterial endothelial monolayers to tumor necrosis factor (TNF)-α causes both a reorganization and/or disruption of fibronectin (Fn) in the extracellular matrix and an increase in transendothelial protein permeability. However, the factors initiating this response to TNF-α have not been defined. Because TNF-α can induce proteinase expression in endothelial cells, we determined whether proteinases cause both the alteration of the Fn matrix and the permeability increase as is often speculated. Incubation of calf pulmonary arterial endothelial monolayers with TNF-α (200 U/ml) for 18 h caused a disruption of the Fn matrix and an increase in transendothelial protein permeability. A reduced colocalization of cell-surface α5β1-Fn integrins with the Fn fibers in focal contacts was also observed. TNF-α treatment of endothelial monolayers with matrices prelabeled with125I-human Fn (hFn) did not cause the release of Fn fragments or alter the content of Fn antigen in the medium as analyzed by SDS-PAGE coupled with autoradiography. Both the content and fragmentation pattern of Fn within the cell layer and the insoluble Fn matrix also appeared unchanged after TNF-α exposure as confirmed by Western immunoblot. Fn-substrate zymography revealed that TNF-α increased the expression of two proteinases within the conditioned medium in which activity could be blocked by aprotinin but not by EDTA, 1,10-phenanthroline, leupeptin, or pepstatin. However, inhibition of the Fn proteolytic activity of these two serine proteinases did not prevent either the TNF-α-induced disruption of the Fn matrix or the increase in permeability. Thus the reorganization and/or disruption of the Fn matrix and the temporally associated increase in endothelial permeability caused by TNF-α appear not to be due to proteolytic degradation of Fn within the extracellular matrix. In contrast, decreased α5β1-Fn integrin interaction with Fn fibers in the matrix may be important in the response to TNF-α exposure.

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Vascular endothelial growth factor-A signaling in bone marrow-derived endothelial progenitor cells exposed to hypoxic stress

Physiological Genomics ◽

10.1152/physiolgenomics.00070.2013 ◽

2013 ◽

Vol 45 (21) ◽

pp. 1021-1034 ◽

Cited By ~ 22

Author(s):

Brian R. Hoffmann ◽

Jordan R. Wagner ◽

Anthony R. Prisco ◽

Agnieszka Janiak ◽

Andrew S. Greene

Keyword(s):

Bone Marrow ◽

Vascular Endothelial Growth Factor ◽

Growth Factor ◽

Signaling Pathways ◽

Progenitor Cells ◽

Endothelial Progenitor Cells ◽

Tube Formation ◽

Vascular Endothelial ◽

Endothelial Progenitor ◽

Endothelial Growth Factor

Bone marrow-derived endothelial progenitor cells (BM-EPCs) are stimulated by vascular endothelial growth factor-A (VEGF-A) and other potent proangiogenic factors. During angiogenesis, an increase in VEGF-A expression stimulates BM-EPCs to enhance endothelial tube formation and contribute to an increase in microvessel density. Hypoxia is known to produce an enhanced angiogenic response and heightened levels of VEGF-A have been seen in oxygen deprived epithelial and endothelial cells, yet the pathways for VEGF-A signaling in BM-EPCs have not been described. This study explores the influence of hypoxia on VEGF-A signaling in rat BM-EPCs utilizing a novel proteomic strategy to directly identify interacting downstream components of the combined VEGF receptor(s) signaling pathways, gene expression analysis, and functional phenotyping. VEGF-A signaling network analysis following liquid chromatographic separation and tandem mass spectrometry revealed proteins related to inositol/calcium signaling, nitric oxide signaling, cell survival, cell migration, and inflammatory responses. Alterations in BM-EPC expression of common angiogenic genes and tube formation in response to VEGF-A during hypoxia were measured and combined with the proteomic analysis to enhance and support the signaling pathways detected. BM-EPC tube formation assays in response to VEGF-A exhibited little tube formation; however, a cell projection/migratory phenotype supported the signaling data. Additionally, a novel assay measuring BM-EPC incorporation into preformed endothelial cell tubes indicated a significant increase of incorporated BM-EPCs after pretreatment with VEGF-A during hypoxia. This study verifies known VEGF-A pathway components and reveals several unidentified mechanisms of VEGF-A signaling in BM-EPCs during hypoxia that may be important for migration to sites of vascular regeneration.

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Vascular Endothelial Growth Factor‐A signaling in Bone Marrow‐Derived Endothelial Progenitor Cells Exposed to Hypoxia

The FASEB Journal ◽

10.1096/fasebj.27.1_supplement.685.7 ◽

2013 ◽

Vol 27 (S1) ◽

Author(s):

Brian Robert Hoffmann ◽

Jordan R. Wagner ◽

Anthony R. Prisco ◽

Andrew S. Greene

Keyword(s):

Bone Marrow ◽

Vascular Endothelial Growth Factor ◽

Growth Factor ◽

Progenitor Cells ◽

Endothelial Progenitor Cells ◽

Vascular Endothelial ◽

Endothelial Progenitor ◽

Endothelial Growth Factor

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Evidence for Clonality in Circulating Endothelial Progenitor Cells in Multiple Myeloma.

Blood ◽

10.1182/blood.v104.11.2357.2357 ◽

2004 ◽

Vol 104 (11) ◽

pp. 2357-2357

Author(s):

Tayfun Ozcelik ◽

Varsha Vakil ◽

Eric Smith ◽

Marc Braunstein ◽

Justin Maroney ◽

...

Keyword(s):

Multiple Myeloma ◽

Bone Marrow ◽

Endothelial Cells ◽

Progenitor Cells ◽

Endothelial Progenitor Cells ◽

X Chromosome ◽

X Chromosome Inactivation ◽

Chromosome Inactivation ◽

M Protein ◽

Vascular Endothelial

Abstract A governing role for neoangiogenesis in the progression of multiple myeloma (MM) is indicated by the finding in patients of increased bone marrow microvascular density that is positively correlated with disease activity and is attenuated by treatment with thalidomide. Bone marrow angiogenesis in MM is largely driven by autocrine and paracrine effects of vascular endothelial growth factor (VEGF) via VEGF receptor-2 (KDR). Elucidation of the role of neovascularization in MM growth and dissemination is likely to result in identification of better therapeutic targets than those currently available as well as provide insight into the pathogenesis of MM. Circulating endothelial cells (CECs) contribute to angiogenesis and comprise mature ECs and endothelial progenitor cells (EPCs). The present study sought to characterize CECs and their relation to disease severity in MM. CECs, identified as CD34+/CD146+/CD105+/CD11− cells, were 6-fold higher in patients compared to controls, and correlated positively with serum M protein and β2-microglobulin (P<.001 for both). In addition, circulating EPCs displayed late colony formation/outgrowth and capillary-like network formation on Matrigel. Effective thalidomide treatment inhibited these characteristics (P<.001). Co-expression of KDR and early vascular antigen CD133 characterized EPCs in MM, and KDR mRNA elevations correlated positively with M protein levels (P<.01). To evaluate the clonality of circulating EPCs, X-chromosome inactivation patterns were quantitated in female patients by human androgen receptor gene (HUMARA) assay. Radioactive (α-[33P] -dCTP) polymerase chain reaction amplification of DNA extracted from peripheral blood mononuclear cells showed that X-chromosome inactivation status was informative in 9 of the 11 MM patients. Distribution of the X-inactivation profiles according to age did not show a shift towards the skewed range in older patients or controls. DNA obtained from confluent EPCs outgrown from 4 informative patients showed an extremely skewed pattern of X-chromosome inactivation, with allele ratios of 90/10% in one patient and 97/3% in another patient, whereas a random pattern of X-chromosome inactivation was observed in two other patients displaying clonal restriction (allele ratios of 55/45% and 54/46%). Collectively, these data underscore the angiogenic aspect of MM and suggest that angioblast-like EPCs are a pathogenic biomarker and a rational treatment target in MM. Furthermore, the clonality of EPCs in MM suggests that the pathogenesis of MM may be tightly related to vascular endothelial cells both at the functional/angiogenic and at the genetic and ontogenic levels.

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