scholarly journals Functional consequences of inhibiting exocytosis of Weibel-Palade bodies in acute renal ischemia

2012 ◽  
Vol 302 (6) ◽  
pp. F713-F721 ◽  
Author(s):  
Kaoru Yasuda ◽  
Radovan Vasko ◽  
Peter Hayek ◽  
Brian Ratliff ◽  
Hasan Bicer ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Renal Injury ◽  
Inhibitory Effect ◽  
Renal Ischemia ◽  
Hematopoietic Stem ◽  
Aortic Endothelial Cells ◽  
Point Tracking ◽  
Inflammatory Protein ◽  
Acute Renal Ischemia

Exocytosis of Weibel-Palade bodies (WPB) represents a distinct response of endothelial cells to stressors, and local release of WPB contents leads to systemic escalation of this response. We synthesized a glycine-(Nα-Et)lysine-proline-arginine (ITF 1697) peptide that has a potential to inhibit exocytosis of WPB and protect microcirculation. Here, we confirmed an inhibitory effect of ITF 1697 using intravital videoimaging and point-tracking of individual organelles. In an in vivo study, mice were implanted with Alzet osmotic pumps (10 μg ITF 1697·kg−1·min−1 at volume of 1 μl/h) and subjected to renal ischemia (IRI). IRI resulted in marked renal injury and elevation of serum creatinine in mice treated with a vehicle. In contrast, renal injury and elevation of creatinine were significantly ameliorated in mice subjected to IRI and receiving ITF 1697. ITF 1697 prevented a systemic response to IRI: a significant surge in the levels of eotaxin and IL-8 (KC; both components of WPB), IL-1α, IL-1β, and RANTES was all prevented or blunted by the administration of ITF 1697, whereas the levels of an anti-inflammatory, IL-10, and macrophage inflammatory protein-1α were upregulated in ITF 1697-treated animals. En face staining of aortic endothelial cells showed that WPB were depleted after 40–180 min post-IRI, and this was significantly blunted in aortic preparations obtained from mice treated with ITF 1697. WPB exocytosis contributed to IRI-associated mobilization of endothelial progenitor cells and hematopoietic stem cells, and ITF 1697 blunted their mobilization. Unexpectedly, 1 mo after IRI, mice treated with ITF 1697 showed a significantly more pronounced degree of scarring than nontreated animals. In conclusion, 1) application of ITF 1697 inhibits exocytosis of WPB and IRI; 2) the systemic inflammatory response of IRI is in part due to the exocytosis of WPB and its blockade blunts it; and 3) ITF 1697 improves short-term renal function after IRI, but not the long-term fibrotic complications.

scholarly journals Urea transporters are distributed in endothelial cells and mediate inhibition of l-arginine transport

2002 ◽  
Vol 283 (3) ◽  
pp. F578-F582 ◽  
Author(s):  
Laszlo Wagner ◽  
Janet D. Klein ◽  
Jeff M. Sands ◽  
Chris Baylis
Keyword(s):  
Endothelial Cells ◽  
Cell Types ◽  
Inhibitory Effect ◽  
Rat Aorta ◽  
Wide Distribution ◽  
Aortic Endothelial Cells ◽  
Bovine Aortic Endothelial Cells ◽  
Elevated Blood Urea Nitrogen ◽  
Aortic Endothelial

Our laboratory previously reported that uremic levels of urea inhibitl-arginine (l-Arg) transport into endothelial cells. The present study further investigated this effect. We measuredl-Arg transport in cultured bovine aortic endothelial cells with normal or high urea (25 mM). The urea transport inhibitor phloretin abolished the inhibitory effect of urea on l-Arg transport, suggesting a role for urea transporters (UTs). We screened bovine aortic endothelial cells and several other endothelial cell types for the presence of UTs by using Western blot analysis. UT-B was present in all endothelial cells, irrespective of species or location of derivation, whereas UT-A distribution was variable and sparse. UT-B was also abundant in rat aorta, mesenteric blood vessels, and spinotrapezius muscle, whereas UT-A distribution was, again, variable and sparse. Chronic elevation of urea had variable, inconsistent effects on UT abundance. This study showed that urea must enter endothelial cells, probably by UT-B, to inhibit l-Arg transport. In view of the wide distribution of UT-B in rat vasculature, elevated blood urea nitrogen may lead to endothelial l-Arg deficiency in vivo.

Effects of Dipyrone on Prostaglandin Production by Human Platelets and Cultured Bovine Aortic Endothelial Cells

1983 ◽  
Vol 49 (02) ◽  
pp. 132-137 ◽  
Author(s):  
A Eldor ◽  
G Polliack ◽  
I Vlodavsky ◽  
M Levy
Keyword(s):  
Endothelial Cells ◽  
Arachidonic Acid ◽  
Competitive Inhibition ◽  
Inhibitory Effect ◽  
Human Platelets ◽  
Ionophore A23187 ◽  
Aortic Endothelial Cells ◽  
Bovine Aortic Endothelial Cells ◽  
Aortic Endothelial

SummaryDipyrone and its metabolites 4-methylaminoantipyrine, 4-aminoantipyrine, 4-acetylaminoantipyrine and 4-formylaminoan- tipyrine inhibited the formation of thromboxane A2 (TXA2) during in vitro platelet aggregation induced by ADP, epinephrine, collagen, ionophore A23187 and arachidonic acid. Inhibition occurred after a short incubation (30–40 sec) and depended on the concentration of the drug or its metabolites and the aggregating agents. The minimal inhibitory concentration of dipyrone needed to completely block aggregation varied between individual donors, and related directly to the inherent capacity of their platelets to synthesize TXA2.Incubation of dipyrone with cultured bovine aortic endothelial cells resulted in a time and dose dependent inhibition of the release of prostacyclin (PGI2) into the culture medium. However, inhibition was abolished when the drug was removed from the culture, or when the cells were stimulated to produce PGI2 with either arachidonic acid or ionophore A23187.These results indicate that dipyrone exerts its inhibitory effect on prostaglandins synthesis by platelets or endothelial cells through a competitive inhibition of the cyclooxygenase system.

Live imaging of Runx1 expression in the dorsal aorta tracks the emergence of blood progenitors from endothelial cells

Blood ◽  
2010 ◽  
Vol 116 (6) ◽  
pp. 909-914 ◽  
Author(s):  
Enid Yi Ni Lam ◽  
Christopher J. Hall ◽  
Philip S. Crosier ◽  
Kathryn E. Crosier ◽  
Maria Vega Flores
Keyword(s):  
Endothelial Cells ◽  
Transcription Factor ◽  
Fluorescent Protein ◽  
Living Organism ◽  
Time Lapse ◽  
Dorsal Aorta ◽  
Transgenic Zebrafish ◽  
Hematopoietic Stem ◽  
Green Fluorescent

Abstract Blood cells of an adult vertebrate are continuously generated by hematopoietic stem cells (HSCs) that originate during embryonic life within the aorta-gonad-mesonephros region. There is now compelling in vivo evidence that HSCs are generated from aortic endothelial cells and that this process is critically regulated by the transcription factor Runx1. By time-lapse microscopy of Runx1-enhanced green fluorescent protein transgenic zebrafish embryos, we were able to capture a subset of cells within the ventral endothelium of the dorsal aorta, as they acquire hemogenic properties and directly emerge as presumptive HSCs. These nascent hematopoietic cells assume a rounded morphology, transiently occupy the subaortic space, and eventually enter the circulation via the caudal vein. Cell tracing showed that these cells subsequently populated the sites of definitive hematopoiesis (thymus and kidney), consistent with an HSC identity. HSC numbers depended on activity of the transcription factor Runx1, on blood flow, and on proper development of the dorsal aorta (features in common with mammals). This study captures the earliest events of the transition of endothelial cells to a hemogenic endothelium and demonstrates that embryonic hematopoietic progenitors directly differentiate from endothelial cells within a living organism.

Abstract 11890: S100A8/A9 is Increased in Psoriasis Serum, Relates to Vascular Diseases and Activates Human Endothelial Cells

Circulation ◽  
2015 ◽  
Vol 132 (suppl_3) ◽  
Author(s):  
Heather Teague ◽  
Qimin Ng ◽  
Monica Purmalek ◽  
Balaji Natarajan ◽  
Taufiq Salahuddin ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Fdg Pet ◽  
Vascular Inflammation ◽  
Vascular Diseases ◽  
Aortic Endothelial Cells ◽  
Pet Ct ◽  
Calcified Plaque ◽  
Fdg Pet Ct ◽  
Psoriasis Severity

Introduction: Psoriasis is a chronic inflammatory disorder of the skin affecting 2-4% of the population and is associated with an increased risk of cardiovascular events, specifically myocardial infarction. Methods: In a large, ongoing prospective cohort study of psoriasis and cardiovascular diseases (NCT01778569), we studied a consecutive sample (n=100) and aimed to investigate the potential role that S100A8/A9 may have in linking psoriasis to CV disease measured by FDG PET CT and coronary CTA. Furthermore, we conducted in vitro experiments on human aortic endothelial cells (ECs) to examine whether treatement with S100A9 activates these cells. We hypothesized that S100A8/A9 would relate to psoriasis severity, relate to in vivo vascular inflammation by FDG PET CT, non-calcified burden of coronary disease by CCTA and increase endothelial cell activation. Results: We observed that the S100A8/A9 heterodimer was elevated in serum (mean psoriasis: 2019 ± 100.1; non-psoriasis: 1634 ± 160.7; p = 0.02), correlating both with psoriasis severity score (adjusted β = 0.53, p = 0.02) and overall aortic vascular inflammation measured by FDG PET CT (adjusted β = 0.48, p = 0.02) beyond the Framingham Risk Score. Additionally, we found that S100A8/A9 was associated with direct coronary atherosclerosis measured by coronary CTA demonstrating an increase in total (β = 0.16, p = 0.04) and non-calcified plaque burden (β = 0.23, p = 0.003) but not dense calcified burden. When EC's were treated with S100A9, ICAM1, E-Selectin and VCAM1 gene expression levels increased 10-fold (p = 0.001), 86-fold (P = 0.007) and 20-fold (p = 0.0002) respectively compared to the untreated human aortic endothelial cells. Conclusions: S100A8/A9 related to psoriasis severity, in vivo vascular inflammation, non-calcified plaque in the coronary arteries and EC activation. These findings suggest this protein may play a role in linking psoriasis to CVD and a role in early atherosclerotic plaque formation. Ongoing studies aim to elucidate the source of S100A8/A9 in the blood and to characterize the signaling pathway utilized by S100A8/A9 to understand whether this pathway is broadly applicable to vascular diseases associated with chronic inflammation.

Stromal Derived Factor-1–Induced Chemokinesis of Cord Blood CD34+ Cells (Long-Term Culture-Initiating Cells) Through Endothelial Cells Is Mediated by E-Selectin

Blood ◽  
1999 ◽  
Vol 94 (12) ◽  
pp. 4011-4019 ◽  
Author(s):  
Afzal J. Naiyer ◽  
Deog-Yeon Jo ◽  
Jongcheol Ahn ◽  
Robert Mohle ◽  
Mario Peichev ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Adhesion Molecules ◽  
Constitutive Expression ◽  
Transendothelial Migration ◽  
Hematopoietic Stem ◽  
Long Term Culture ◽  
Migration System ◽  
Cd34 Cells

Abstract Homing of hematopoietic stem cells to the bone marrow (BM) involves sequential interaction with adhesion molecules expressed on BM endothelium (BMEC) and chemokine stromal derived factor-1 (SDF-1). However, the mechanism whereby adhesion molecules regulate the SDF-1–induced transendothelial migration process is not known. E-selectin is an endothelial-specific selectin that is constitutively expressed by the BMEC in vivo. Hence, we hypothesized that E-selectin may mediate SDF-1–induced transendothelial migration of CD34+ cells. We show that CD34+ cells express both E-selectin ligand and fucosyltransferase-VII (FucT-VII). Soluble E-selectin–IgG chimera binds avidly to 75% ± 10% of CD34+ cells composed mostly of progenitors and cells with long-term culture-initiating cell (LTC-IC) potential. To assess the functional capacity of E-selectin to mediate CD34+ cell migration in a transendothelial migration system, CD34+ cells were placed on transwell plates coated with interleukin-1β–activated BMEC. In the absence of SDF-1, there was spontaneous migration of 7.0% ± 1.4% of CD34+ cells and 14.1% ± 2.2% of LTC-IC. SDF-1 induced migration of an additional 23.0% ± 4.4% of CD34+cells and 17.6% ± 3.6% of LTC-IC. Blocking MoAb to E-selectin inhibited SDF-1–induced migration of CD34+ cells by 42.0% ± 2.5% and LTC-IC by 90.9% ± 16.6%. To define the mechanism of constitutive expression of E-selectin by the BMEC in vivo, we have found that vascular endothelial growth factor (VEGF165) induces E-selectin expression by cultured endothelial cells. VEGF-stimulated endothelial cells support transendothelial migration of CD34+ cells that could be blocked by MoAb to E-selectin. These results suggest that trafficking of subsets of CD34+ cells with LTC-IC potential is determined in part by sequential interactions with E-selectin and SDF-1.

scholarly journals Use of 5-fluorouracil to analyze the effect of macrophage inflammatory protein-1 alpha on long-term reconstituting stem cells in vivo

Blood ◽  
1993 ◽  
Vol 81 (6) ◽  
pp. 1497-1504 ◽  
Author(s):  
VF Quesniaux ◽  
GJ Graham ◽  
I Pragnell ◽  
D Donaldson ◽  
SD Wolpe ◽  
...  
Keyword(s):  
Stem Cells ◽  
Bone Marrow ◽  
Inhibitory Effect ◽  
In Vivo Model ◽  
Hematopoietic Progenitors ◽  
Inflammatory Protein ◽  
Macrophage Inflammatory Protein

Abstract A macrophage-derived inhibitor of early hematopoietic progenitors (colony-forming unit-spleen, CFU-A) called stem cell inhibitor was found to be identical to macrophage inflammatory protein-1 alpha (MIP-1 alpha). We investigated the effect of MIP-1 alpha on the earliest stem cells that sustain long-term hematopoiesis in vivo in a competitive bone marrow repopulation assay. Because long-term reconstituting (LTR) stem cells are normally quiescent, an in vivo model was first developed in which they are triggered to cycle. A first 5-fluorouracil (5-FU) injection was used to eliminate later progenitors, causing the LTR stem cells, which are normally resistant to 5-FU, to enter the cell cycle and become sensitive to a second 5-FU injection administered 5 days later. Human MIP-1 alpha administered from day 0 to 7 was unable to prevent the depletion of the LTR stem cells by the second 5-FU treatment, as observed on day 7 in this model, suggesting that the LTR stem cells were not prevented from being triggered into cycle despite the MIP-1 alpha treatment. However, the MIP-1 alpha protocol used here did substantially decrease the number of more mature hematopoietic progenitors (granulocyte-macrophage colony-forming cells [CFC], burst- forming unit-erythroid, CFCmulti, and preCFCmulti) recovered in the bone marrow shortly after a single 5-FU injection. In vitro, MIP-1 alpha had no inhibitory effect on the ability of these progenitors to form colonies. This study confirms the in vivo inhibitory effect of MIP- 1 alpha on subpopulations of hematopoietic progenitors that are activated in myelodepressed animals. However, MIP-1 alpha had no effect on the long-term reconstituting stem cells in vivo under conditions in which it effectively reduced all later progenitors.

Role of endothelial cells in regulating hemoglobin-induced changes in lymphatic pumping

1992 ◽  
Vol 263 (6) ◽  
pp. H1880-H1887 ◽  
Author(s):  
R. M. Elias ◽  
J. Eisenhoffer ◽  
M. G. Johnston
Keyword(s):  
Endothelial Cells ◽  
Smooth Muscle ◽  
Inhibitory Effect ◽  
Direct Inhibitory Effect ◽  
Induced Changes ◽  
Lymphatic Pumping ◽  
Pumping Activity

Studies with a sheep isolated duct preparation in vivo demonstrated that the route of administration of hemoglobin was important in demonstrating its inhibitory effect on lymphatic pumping. With autologous oxyhemoglobin administered intravenously (final plasma concentration 5 x 10(-5) M), pumping was not inhibited. However, the addition of oxyhemoglobin (5 x 10(-5) M) into the reservoir (lumen of the duct) resulted in > 95% inhibition of pumping. The extraluminal administration of oxyhemoglobin (10(-5) M) to bovine mesenteric lymphatics in vitro resulted in a 40% inhibition of pumping, whereas the introduction of oxyhemoglobin (10(-5) M) into the lumen of the vessels suppressed pumping 95%. In vessels mechanically denuded of endothelium, intraluminal oxyhemoglobin inhibited pumping 50%. These results suggested that oxyhemoglobin depressed pumping through an effect on both smooth muscle and endothelium. Once pumping was inhibited with oxyhemoglobin administration, stimulation of the duct with elevations in transmural pressure restored pumping activity when endothelial cells were present. However, in the absence of endothelium, pumping decreased with increases in distending pressures. We conclude that oxyhemoglobin has a direct inhibitory effect on lymphatic smooth muscle. The ability of oxyhemoglobin to alter the pressure range over which the lymph pump operates appears to be dependent on an intact endothelium.

scholarly journals Gangliosides Contribute to Vascular Insulin Resistance

2019 ◽  
Vol 20 (8) ◽  
pp. 1819 ◽  
Author(s):  
Norihiko Sasaki ◽  
Yoko Itakura ◽  
Masashi Toyoda
Keyword(s):  
Insulin Resistance ◽  
Endothelial Cells ◽  
Vascular Function ◽  
Molecular Mechanisms ◽  
The Elderly ◽  
Necrosis Factor Alpha ◽  
Aortic Endothelial Cells ◽  
Inflammatory Conditions ◽  
Factor Alpha

Insulin in physiological concentrations is important to maintain vascular function. Moreover, vascular insulin resistance contributes to vascular impairment. In the elderly, other factors including hypertension, dyslipidemia, and chronic inflammation amplify senescence of vascular endothelial and smooth muscle cells. In turn, senescence increases the risk for vascular-related diseases such as arteriosclerosis, diabetes, and Alzheimer’s disease. Recently, it was found that GM1 ganglioside, one of the glycolipids localized on the cell membrane, mediates vascular insulin resistance by promoting senescence and/or inflammatory stimulation. First, it was shown that increased GM1 levels associated with aging/senescence contribute to insulin resistance in human aortic endothelial cells (HAECs). Second, the expression levels of gangliosides were monitored in HAECs treated with different concentrations of tumor necrosis factor-alpha (TNFα) for different time intervals to mimic in vivo acute or chronic inflammatory conditions. Third, the levels of insulin signaling-related molecules were monitored in HAECs after TNFα treatment with or without inhibitors of ganglioside synthesis. In this review, we summarize the molecular mechanisms of insulin resistance in aged/senescent and TNFα-stimulated endothelial cells mediated by gangliosides and highlight the possible roles of gangliosides in vascular insulin resistance-related diseases.

Endopeptidases 3.4.24.15 and 24.16 in endothelial cells: potential role in vasoactive peptide metabolism

2003 ◽  
Vol 284 (6) ◽  
pp. H1978-H1984 ◽  
Author(s):  
M. Ursula Norman ◽  
Shane B. Reeve ◽  
Vincent Dive ◽  
A. Ian Smith ◽  
Rebecca A. Lew
Keyword(s):  
Endothelial Cells ◽  
High Performance ◽  
Vascular Endothelial Cells ◽  
Umbilical Vein ◽  
Hybrid Cell ◽  
Fluorescent Substrate ◽  
Intact Cells ◽  
Aortic Endothelial Cells

The closely related metalloendopeptidases EC 3.4.24.15 (EP24.15; thimet oligopeptidase) and 24.16 (EP24.16; neurolysin) cleave a number of vasoactive peptides such as bradykinin and neurotensin in vitro. We have previously shown that hypotensive responses to bradykinin are potentiated by an inhibitor of EP24.15 and EP24.16 (26), suggesting a role for one or both enzymes in bradykinin metabolism in vivo. In this study, we have used selective inhibitors that can distinguish between EP24.15 and EP24.16 to determine their activity in cultured endothelial cells (the transformed human umbilical vein endothelial hybrid cell line EA.hy926 or ovine aortic endothelial cells). Endopeptidase activity was assessed using a specific quenched fluorescent substrate [7-methoxycoumarin-4-acetyl-Pro-Leu-Gly-d-Lys(2,4-dinitrophenyl)], as well as the peptide substrates bradykinin and neurotensin (assessed by high-performance liquid chromatography with mass spectroscopic detection). Our results indicate that both peptidases are present in endothelial cells; however, EP24.16 contributes significantly more to substrate cleavage by both cytosolic and membrane preparations, as well as intact cells, than EP24.15. These findings, when coupled with previous observations in vivo, suggest that EP24.16 activity in vascular endothelial cells may play an important role in the degradation of bradykinin and/or other peptides in the circulation.

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