Impaired Prostacyclin Synthesis of Endothelial Cells Derived from Hypertensive Calf Pulmonary Arteries

2015 ◽  
pp. 63-69 ◽  
Author(s):  
N. F. Voelkel ◽  
D. B. Badesch ◽  
L. M. Zapp ◽  
K. R. Stenmark
Keyword(s):  
Endothelial Cells ◽  
Pulmonary Arteries ◽  
Prostacyclin Synthesis

Proproliferative phenotype of pulmonary microvascular endothelial cells

2007 ◽  
Vol 292 (3) ◽  
pp. L671-L677 ◽  
Author(s):  
Victor Solodushko ◽  
Brian Fouty
Keyword(s):  
Endothelial Cells ◽  
Barrier Function ◽  
Pulmonary Arteries ◽  
D1 Protein ◽  
Coagulation Cascade ◽  
Microvascular Endothelial Cells ◽  
Significant Heterogeneity ◽  
Pulmonary Microvascular Endothelial Cells ◽  
Microvascular Endothelial ◽  
Pulmonary Microcirculation

Endothelial cells perform a number of important functions including release of vasodilators, control of the coagulation cascade, and restriction of solutes and fluid from the extravascular space. Regulation of fluid balance is of particular importance in the microcirculation of the lung where the loss of endothelial barrier function can lead to alveolar flooding and life-threatening hypoxemia. Significant heterogeneity exists between endothelial cells lining the microcirculation and cells from larger pulmonary arteries, however, and these differences may be relevant in restoring barrier function following vascular injury. Using well-defined populations of rat endothelial cells harvested from the pulmonary microcirculation [pulmonary microvascular endothelial cells (PMVEC)] and from larger pulmonary arteries [pulmonary artery endothelial cells (PAEC)], we compared their growth characteristics in low serum conditions. Withdrawal of serum inhibited proliferation and induced G0/G1 arrest in PAEC, whereas PMVEC failed to undergo G0/G1 arrest and continued to proliferate. Consistent with this observation, PMVEC had an increased cdk4 and cdk2 kinase activity with hyperphosphorylated (inactive) retinoblastoma (Rb) relative to PAEC as well as a threefold increase in cyclin D1 protein levels; overexpression of the cdk inhibitors p21Cip1/Waf1 and p27Kip1 induced G0/G1 arrest. While serum withdrawal failed to induce G0/G1 arrest in nonconfluent PMVEC, confluence was associated with hypophosphorylated Rb and growth arrest; loss of confluence led to resumption of growth. These data suggest that nonconfluent PMVEC continue to proliferate independently of growth factors. This proliferative characteristic may be important in restoring confluence (and barrier function) in the pulmonary microcirculation following endothelial injury.

Purified verotoxins of Escherichia coli O157:H7 decrease prostacyclin synthesis by endothelial cells

1988 ◽  
Vol 5 (3) ◽  
pp. 215-221 ◽  
Author(s):  
Helge Karch ◽  
Martin Bitzan ◽  
Ralf Pietsch ◽  
Karl-Otmar Stenger ◽  
Hinrik von Wulffen ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Endothelial Cells ◽  
Escherichia Coli O157 ◽  
Prostacyclin Synthesis

scholarly journals Platelet-derived growth factor does not stimulate prostacyclin synthesis by cultured endothelial cells

Blood ◽  
1986 ◽  
Vol 67 (1) ◽  
pp. 131-134
Author(s):  
KS Callahan ◽  
A Schorer ◽  
JM Harlan
Keyword(s):  
Endothelial Cells ◽  
Growth Factor ◽  
Umbilical Vein ◽  
Platelet Derived Growth Factor ◽  
Human Endothelial Cells ◽  
Aortic Endothelial Cells ◽  
Bovine Aortic Endothelial Cells ◽  
Prostacyclin Synthesis ◽  
Release Product ◽  
Stimulation Of

We examined the effect of highly purified platelet-derived growth factor (PDGF) on prostacyclin (PGI2) release by cultured human umbilical vein and bovine aortic endothelial cells. PDGF tested at concentrations equal to or exceeding those observed in serum did not increase endothelial cell PGI2 synthesis as measured by radioimmunoassay of its metabolite, 6-keto-PGF1 alpha. In contrast, cells incubated with 20% human whole blood serum (WBS) demonstrated significantly increased PGI2 production (fivefold stimulation). Addition of anti-PDGF antibody to the 20% WBS did not attenuate the increased synthesis of PGI2. Incubation with 20% plasma-derived serum (PDS) that was deficient in PDGF produced stimulation of PGI2 release similar to 20% WBS. These results demonstrate that PDGF does not cause increased PGI2 synthesis in cultured human endothelial cells of human or bovine origin, and further suggest that the stimulation observed with serum is not due to a platelet-release product.

Notch2 Suppression Mimicking Changes in Human Pulmonary Hypertension Modulates Notch1 and Promotes Endothelial Cell Proliferation

2021 ◽  
Author(s):  
Sanghamitra Sahoo ◽  
Yao Li ◽  
Daniel de Jesus ◽  
John Charles Sembrat II ◽  
Mauricio M Rojas ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Endothelial Cells ◽  
Endothelial Cell ◽  
Target Genes ◽  
Pulmonary Arteries ◽  
Notch Receptor ◽  
Endothelial Cell Proliferation ◽  
Tissue Samples ◽  
Endothelial Proliferation ◽  
Human Pulmonary Artery

Pulmonary arterial hypertension (PAH) is a fatal cardiopulmonary disease characterized by increased vascular cell proliferation with resistance to apoptosis and occlusive remodeling of the small pulmonary arteries in humans. The Notch family of proteins are proximal signaling mediators of an evolutionarily conserved pathway that effect cell proliferation, fate determination, and development. In endothelial cells (ECs), Notch receptor 2 (Notch2) has been shown to promote endothelial apoptosis. However, a pro- or anti-proliferative role for Notch2 in pulmonary endothelial proliferation and ensuing PAH is unknown. Herein, we postulated that suppressed Notch2 signaling drives pulmonary endothelial proliferation in the setting of PAH. We observed that levels of Notch2 are ablated in lung and PA tissue samples from PAH patients compared to non-PAH controls. Interestingly, Notch2 expression was attenuated in human pulmonary artery endothelial cells (hPAECs) exposed to vasoactive factors including hypoxia, TGFβ, ET-1, and IGF-1. Gene silencing of Notch2 increased EC proliferation and reduced apoptosis. At the molecular level, Notch2-deficient hPAECs activated Akt, Erk1/2 and anti-apoptotic protein Bcl-2, and reduced levels of p21cip and Bax. Intriguingly, loss of Notch2 elicits a paradoxical activation of Notch1 and transcriptional upregulation of canonical Notch target genes Hes1, Hey1 and Hey2. Further, reduction in Rb and increased E2F1 binding to the Notch1 promoter appear to explain the upregulation of Notch1. In aggregate, our results demonstrate that loss of Notch2 derepresses Notch1 and elicits aberrant EC hallmarks of PAH. The data underscore a novel role for Notch in the maintenance of endothelial cell homeostasis.

scholarly journals Mechanisms involved in the stimulation of prostacyclin synthesis by human lymphocytes in human umbilical vein endothelial cells

2003 ◽  
Vol 139 (2) ◽  
pp. 321-328 ◽  
Author(s):  
Faten Merhi-Soussi ◽  
Zury Dominguez ◽  
Olga Macovschi ◽  
Madeleine Dubois ◽  
Georges Nemoz ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Umbilical Vein ◽  
Human Lymphocytes ◽  
Human Umbilical Vein ◽  
Umbilical Vein Endothelial Cells ◽  
Prostacyclin Synthesis ◽  
Stimulation Of

Newborn piglet lungs release endothelin-1: effect of α-thrombin and hypoxia

1993 ◽  
Vol 71 (3-4) ◽  
pp. 227-233 ◽  
Author(s):  
T. Perreault ◽  
D. J. Stewart ◽  
P. Cernacek ◽  
X. Wu ◽  
F. Ni ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Pulmonary Circulation ◽  
Cellular Localization ◽  
Perfusion Pressure ◽  
Hypoxic Pulmonary Vasoconstriction ◽  
Acute Hypoxia ◽  
Pulmonary Arteries ◽  
Newborn Piglet ◽  
Medium Size ◽  
Endothelin 1

Endothelin-1 (ET-1) is a 21 amino acid vasoconstrictor peptide produced by endothelial cells, the expression of which is modulated by a variety of vasoconstrictors, vasodilators, and inflammatory mediators. Hypoxia has been shown to increase ET-1 expression and release in cultured endothelial cells from the systemic circulation, but reports are contradictory regarding the pulmonary circulation. In this study, the release of ET-1 and its cellular localization in the isolated perfused newborn piglet lung were examined under control conditions and after stimulation with hypoxia or α-thrombin (positive control). In the control condition, perfusion pressure remained stable during the study period, and a progressive increase in levels of immunoreactive ET-1 (irET-1) was noted. When α-thrombin was added to the perfusion fluid, a slow gradual increase in perfusion pressure was produced and the levels of irET-1 were significantly greater than those measured in the control preparations. Finally, hypoxia produced a significant increase in the perfusion pressure; however, the release of irET-1 did not differ significantly from the control, if anything, the net release across the lung was diminished. In all conditions, immunocytochemistry using antiserum to human–porcine ET-1 revealed the presence of high ET-1-like immunoreactivity in epithelial cells of bronchi, bronchioles, and terminal bronchioles. In addition, endothelial cells of large and medium-size pulmonary arteries were only moderately immunoreactive for ET-1. These findings indicate that the neonatal pig lung can produce and release ET-1, and that its release can be increased by certain stimuli like α-thrombin. On the other hand, acute hypoxia does not appear to be an important stimulus to ET-1 in the neonatal pulmonary circulation. Therefore, ET-1 is not likely to be involved in the hypoxic pulmonary vasoconstriction in the newborn piglet.Key words: neonatal pulmonary circulation, endothelium-derived constricting factor.

scholarly journals Hypoxia-inducible factors in human pulmonary arterial hypertension: a link to the intrinsic myeloid abnormalities

Blood ◽  
2011 ◽  
Vol 117 (13) ◽  
pp. 3485-3493 ◽  
Author(s):  
Samar Farha ◽  
Kewal Asosingh ◽  
Weiling Xu ◽  
Jacqueline Sharp ◽  
Deepa George ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Endothelial Cells ◽  
Pulmonary Arterial Hypertension ◽  
Arterial Hypertension ◽  
Hypoxia Inducible Factor ◽  
Pulmonary Arteries ◽  
Disease Process ◽  
Pulmonary Vasculature ◽  
Normal Numbers ◽  
Pulmonary Arterial

AbstractPulmonary arterial hypertension (PAH) is a proliferative vasculopathy characterized by high circulating CD34+CD133+ proangiogenic progenitors, and endothelial cells that have pathologic expression of hypoxia-inducible factor 1 α (HIF-1α). Here, CD34+CD133+ progenitor cell numbers are shown to be higher in PAH bone marrow, blood, and pulmonary arteries than in healthy controls. The HIF-inducible myeloid-activating factors erythropoietin, stem cell factor (SCF), and hepatocyte growth factor (HGF) are also present at higher than normal levels in PAH blood, and related to disease severity. Primary endothelial cells harvested from human PAH lungs produce greater HGF and progenitor recruitment factor stromal-derived factor 1 α (SDF-1α) than control lung endothelial cells, and thus may contribute to bone marrow activation. Even though PAH patients had normal numbers of circulating blood elements, hematopoietic alterations in myeloid and erythroid lineages and reticulin fibrosis identified a subclinical myeloproliferative process. Unexpectedly, evaluation of bone marrow progenitors and reticulin in nonaffected family members of patients with familial PAH revealed similar myeloid abnormalities. Altogether, the results show that PAH is linked to myeloid abnormalities, some of which may be related to increased production of HIF-inducible factors by diseased pulmonary vasculature, but findings in nonaffected family suggest myeloid abnormalities may be intrinsic to the disease process.

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