scholarly journals The Study on Angiotensin II Induced-ferroptosis in Vascular Endothelial Cells

Author(s):  
Hong Fang ◽  
Chi Liu ◽  
Omer Cavdar ◽  
Yi Shen

Abstract Background: To verify the effect of Angiotensin II on ferroptosis in vascular endothelial cells and clarify the related mechanism.Methods: HUVECs were evaluated for p53, P21, ALOX12, VEGF, MDA, GSH. Molecular marker impact upon AngII-induced ferroptosis was evaluated with students’ t-test,one-way analysis of variance (ANOVA).Results: As the concentration of Ang II increased,the level of ALOX12, P53, GSH and MDA increased in HUVECs. The expression of VEGFA in HUVECs is negatively correlated with dose of Ang II. Incubation of HUVECs in AngII and valsartan for 48hr reduces ALOX12, P21, GSH and MDA. Compared with the single AngII group, ALOX12, P21, GSH and MDA in valsartan group was decreased significantly(p=0.000). In pifithrin-α hydrobromide-treated, ALOX12, P21, GSH and MDA was reduced significantly, as compared to valsartan group(p=0.000). The most larger reduction in ALOX12, P21,GSH and MDA was pifithrin - α hydrobromide combined with valsartan group. In contrast, the expression of VEGFA increased significantly after HUVECs were treated with pifithrin - α hydrobromide and valsartan(p=0.000).Conclusions: AngII can induce ferroptosis of vascular endothelial cells in a dose-dependent manner. The mechanism of AngII-induced ferroptosis may be regulated through the signal axis of ATR1,2-p53-ALOX12.

2021 ◽  
Author(s):  
hong fang ◽  
Chi liu ◽  
Omer Cavdar ◽  
Yi Shen

Abstract PurposeTo verify the effect of Angiotensin II on ferroptosis in vascular endothelial cells and clarify the related mechanism. MethodsHUVECs were evaluated for p53, P21,ALOX12, VEGF, MDA,GSH. Molecular marker impact upon AngII-induced ferroptosis was evaluated with students’ t-test,one-way analysis of variance (ANOVA).ResultsAs the concentration of Ang II increased,the level of ALOX12, P53,GSH and MDA increased in HUVECs. The expression of VEGFA in HUVECs is negatively correlated with dose of Ang II. Incubation of HUVECs in AngII and valsartan for 48hr reduces ALOX12, P21, GSH and MDA. Compared with the single AngII group, ALOX12, P21, GSH and MDA in valsartan group was decreased significantly(p=0.000).In pifithrin-α hydrobromide-treated, ALOX12, P21, GSH and MDA was reduced significantly, as compared to valsartan group(p=0.000). The most larger reduction in ALOX12, P21,GSH and MDA was pifithrin - α hydrobromide combined with valsartan group. In contrast, the expression of VEGFA increased significantly after HUVECs were treated with pifithrin - α hydrobromide and valsartan(p=0.000).ConclusionsAngII can induce ferroptosis of vascular endothelial cells in a dose-dependent manner. The mechanism of AngII-induced ferroptosis may be regulated through the signal axis of ATR1,2-p53-ALOX12.


Author(s):  
Yuyu Yang ◽  
Huidi Wang ◽  
Hongwei Zhao ◽  
Xiulian Miao ◽  
Yan Guo ◽  
...  

Endothelin, encoded by ET1, is a vasoactive substance primarily synthesized in vascular endothelial cells (VECs). Elevation of endothelin levels, due to transcriptional hyperactivation, has been observed in a host of cardiovascular diseases. We have previously shown that serum response factor (SRF) is a regulator of ET1 transcription in VECs. Here we report that angiotensin II (Ang II) induced ET1 transcription paralleled activation of glycogen synthase kinase 3 (GSK3) in cultured VECs. GSK3 knockdown or pharmaceutical inhibition attenuated Ang II induced endothelin expression. Of interest, the effect of GSK3 on endothelin transcription relied on the conserved SRF motif within the ET1 promoter. Further analysis revealed that GSK3 interacted with and phosphorylated SRF at serine 224. Phosphorylation of SRF by GSK3 did not influence its recruitment to the ET1 promoter. Instead, GSK3-mediated SRF phosphorylation potentiated its interaction with MRTF-A, a key co-factor for SRF, which helped recruit the chromatin remodeling protein BRG1 to the ET1 promoter resulting in augmented histone H3 acetylation/H3K4 trimethylation. Consistently, over-expression of a constitutively active GSK enhanced Ang II-induced ET1 transcription and knockdown of either MRTF-A or BRG1 abrogated the enhancement of ET1 transcription. In conclusion, our data highlight a previously unrecognized mechanism that contributes to the transcriptional regulation of endothelin. Targeting this GSK3-SRF axis may yield novel approaches in the intervention of cardiovascular diseases.


2006 ◽  
Vol 290 (6) ◽  
pp. C1495-C1502 ◽  
Author(s):  
Hideyuki Yamawaki ◽  
Naoharu Iwai

Nanoscale materials are presently under development for diagnostic (nanomedicine) and electronic purposes. In contrast to the potential benefits of nanotechnology, the effects of nanomaterials on human health are poorly understood. Nanomaterials are known to translocate into the circulation and could thus directly affect vascular endothelial cells (ECs), causing vascular injury that might be responsible for the development of atherosclerosis. To explore the direct effects of nanomaterials on endothelial toxicity, human umbilical vein ECs were treated with 1–100 μg/ml hydroxyl fullerene [C60(OH)24; mean diameter, 7.1 ± 2.4 nm] for 24 h. C60(OH)24 induced cytotoxic morphological changes such as cytosolic vacuole formation and decreased cell density in a dose-dependent manner. Lactate dehydrogenase assay revealed that a maximal dose of C60(OH)24 (100 μg/ml) induced cytotoxic injury. Proliferation assay also showed that a maximal dose of C60(OH)24 inhibited EC growth. C60(OH)24 did not seem to induce apoptosis but caused the accumulation of polyubiquitinated proteins and facilitated autophagic cell death. Formation of autophagosomes was confirmed on the basis of Western blot analysis using a specific marker, light chain 3 antibody, and electron microscopy. Chronic treatment with low-dose C60(OH)24 (10 μg/ml for 8 days) inhibited cell attachment and delayed EC growth. In the present study, we have examined, for the first time, the toxicity of water-soluble fullerenes to ECs. Although fullerenes changed morphology in a dose-dependent manner, only maximal doses of fullerenes caused cytotoxic injury and/or death and inhibited cell growth. EC death seemed to be caused by activation of ubiquitin-autophagy cell death pathways. Although exposure to nanomaterials appears to represent a risk for cardiovascular disorders, further in vivo validations are necessary.


2006 ◽  
Vol 191 (1) ◽  
pp. 171-177 ◽  
Author(s):  
Lachlan J Pearson ◽  
Christopher Rait ◽  
M Gary Nicholls ◽  
Timothy G Yandle ◽  
John J Evans

It is well documented that there are gender differences in the incidence and patterns of cardiovascular diseases but the reasons are unclear. Sex steroids may modulate the behaviour of vascular endothelial cells, which in turn act by paracrine processes to alter adjacent vascular smooth muscle activity. We hypothesised that the sex steroids alter the percentage of vascular endothelial cells that secrete the vasodilator peptide, adrenomedullin and modify the adrenomedullin-stimulating action of angiotensin-II. The percentage of adrenomedullin-secreting human aortic endothelial cells was determined using the cell immunoblot method. Cells were incubated with selected concentrations of angiotensin-II, oestradiol and testosterone alone and sex steroids in combination with angiotensin-II. Adrenomedullin mRNA expression in endothelial cells was quantified by real-time PCR. It was observed that at 4 h, angiotensin-II increased the percentage of adrenomedullin-secreting cells in a concentration-dependent manner. Testosterone at physiological concentrations was observed to increase the number of adrenomedullin-secreting cells whilst oestradiol had no effect. Addition of testosterone to angiotensin-II resulted in less than additive increases in the number of cells secreting adrenomedullin. Oestradiol reduced the angiotensin-II-induced increase in adrenomedullin-secreting cells. Adrenomedullin mRNA expression was significantly increased by testosterone and there was also a trend for an increase in adrenomedullin mRNA expression, which occurred when cells were incubated with angiotensin-II. Our results point to a complex interplay between the sex steroids and angiotensin-II in regulating adrenomedullin production by human endothelial cells, which may contribute to gender-related differences in vascular disease in humans.


1996 ◽  
Vol 270 (3) ◽  
pp. H857-H868 ◽  
Author(s):  
R. M. Touyz ◽  
J. Fareh ◽  
G. Thibault ◽  
B. Tolloczko ◽  
R. Lariviere ◽  
...  

Vasoactive peptides may exert inotropic and chronotropic effects in cardiac muscle by modulating intracellular calcium. This study assesses effects of angiotensin II (ANG II) and endothelin-1 (ET-1) on intracellular free calcium concentration ([Ca2+]i) in cultured cardiomyocytes from neonatal and adult rats. [Ca2+]i was measured microphotometrically and by digital imaging using fura 2 methodology. Receptor subtypes through which these agonists induce responses were determined pharmacologically and by radioligand binding studies. ANG II and ET-1 increased neonatal atrial and ventricular cell [Ca2+]i transients in a dose-dependent manner. ANG II (10(-11) to 10(-7) M) failed to elicit [Ca2+]i responses in adult cardiomyocytes, whereas ET-1 increased [Ca2+]i in a dose-dependent manner. The ETA receptor antagonist BQ-123 significantly reduced (P 7< 0.05) ET-1 induced responses, and the ETB receptor agonist IRL-1620 (10(-7) to 10(-5) M) significantly increased (P < 0.05) [Ca2+]i in neonatal and adult cardiomyocytes. ET-1 binding studies demonstrated 85% displacement by BQ-123 and approximately 15% by the ETB receptor agonist sarafotoxin S6c, suggesting a predominance of ETA receptors. Competition binding studies for ANG II failed to demonstrate significant binding on adult ventricular myocytes, indicating the absence or presence of very few ANG II receptors. These data demonstrate that ANG II and ET-1 have stimulatory [Ca2+]i effects on neonatal cardiomyocytes, whereas in adult cardiomyocytes, ANG II-induced effects are insignificant, and only ET-1-induced responses, which are mediated predominantly via ETA receptors, are preserved. Cardiomyocyte responses to vasoactive peptides may thus vary with cardiac development.


2021 ◽  
Author(s):  
Yi-Ting Yeh ◽  
Danielle E. Skinner ◽  
Ernesto Criado-Hidalgo ◽  
Natalie Shee Chen ◽  
Antoni Garcia-De Herreros ◽  
...  

AbstractThe eggs of the parasitic blood fluke, Schistosoma, are the main drivers of the chronic pathologies associated with schistosomiasis, a disease of poverty afflicting approximately 220 million people worldwide. Eggs laid by Schistosoma mansoni in the bloodstream of the host are encapsulated by vascular endothelial cells (VECs), the first step in the migration of the egg from the blood stream into the lumen of the gut and eventual exit from the body. The biomechanics associated with encapsulation and extravasation of the egg are poorly understood. We demonstrate that S. mansoni eggs induce VECs to form two types of membrane extensions during encapsulation; filopodia that probe eggshell surfaces and intercellular nanotubes that presumably facilitate VEC communication. Encapsulation efficiency, the number of filopodia and intercellular nanotubes, and the length of these structures depend on the egg’s vitality and, to a lesser degree, its maturation state. During encapsulation, live eggs induce VEC contractility and membranous structures formation, in a Rho/ROCK pathway-dependent manner. Using elastic hydrogels embedded with fluorescent microbeads as substrates to culture VECs, live eggs induce VECs to exert significantly greater contractile forces during encapsulation than dead eggs, which leads to 3D deformations on both the VEC monolayer and the flexible substrate underneath. These significant mechanical deformations cause the VEC monolayer tension to fluctuate with eventual rupture of VEC junctions, thus facilitating egg transit out of the blood vessel. Overall, our data on the mechanical interplay between host VECs and the schistosome egg improve our understanding of how this parasite manipulates its immediate environment to maintain disease transmission.


2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Purum Kang ◽  
Seung Ho Han ◽  
Hea Kyung Moon ◽  
Jeong-Min Lee ◽  
Hyo-Keun Kim ◽  
...  

The purpose of the present study is to examine the effects of essential oil ofCitrus bergamiaRisso (bergamot, BEO) on intracellular Ca2+in human umbilical vein endothelial cells. Fura-2 fluorescence was used to examine changes in intracellular Ca2+concentration[Ca2+]i. In the presence of extracellular Ca2+, BEO increased[Ca2+]i, which was partially inhibited by a nonselective Ca2+channel blocker La3+. In Ca2+-free extracellular solutions, BEO increased[Ca2+]iin a concentration-dependent manner, suggesting that BEO mobilizes intracellular Ca2+. BEO-induced[Ca2+]iincrease was partially inhibited by a Ca2+-induced Ca2+release inhibitor dantrolene, a phospholipase C inhibitor U73122, and an inositol 1,4,5-triphosphate (IP3)-gated Ca2+channel blocker, 2-aminoethoxydiphenyl borane (2-APB). BEO also increased[Ca2+]iin the presence of carbonyl cyanide m-chlorophenylhydrazone, an inhibitor of mitochondrial Ca2+uptake. In addition, store-operated Ca2+entry (SOC) was potentiated by BEO. These results suggest that BEO mobilizes Ca2+from primary intracellular stores via Ca2+-induced and IP3-mediated Ca2+release and affect promotion of Ca2+influx, likely via an SOC mechanism.


Blood ◽  
1998 ◽  
Vol 91 (7) ◽  
pp. 2334-2340
Author(s):  
Gian Carlo Avanzi ◽  
Margherita Gallicchio ◽  
Flavia Bottarel ◽  
Loretta Gammaitoni ◽  
Giuliana Cavalloni ◽  
...  

GAS6 is a ligand for the tyrosine kinase receptors Rse, Axl, and Mer, but its function is poorly understood. Previous studies reported that both GAS6 and Axl are expressed by vascular endothelial cells (EC), which play a key role in leukocyte extravasation into tissues during inflammation through adhesive interactions with these cells. The aim of this work was to evaluate the GAS6 effect on the adhesive function of EC. Treatment of EC with GAS6 significantly inhibited adhesion of polymorphonuclear cells (PMN) induced by phorbol 12-myristate 13-acetate (PMA), platelet-activating factor (PAF), thrombin, interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α), but not that induced by FMLP and IL-8. GAS6 did not affect adhesion to resting EC. Titration experiments showed that high concentrations of GAS6 were needed to inhibit PMN adhesion and that inhibition was dose-dependent at the concentration range of 0.1 to 1 μg/mL. One possibility was that high concentrations were needed to overwhelm the effect of endogenous GAS6 produced by EC. In line with this possibility, treatment of resting EC with soluble Axl significantly potentiated PMN adhesion. Analysis of localization of GAS6 by confocal microscopy and cytofluorimetric analysis showed that it is concentrated along the plasma membrane in resting EC and treatment with PAF induces depletion and/or redistribution of the molecule. These data suggest that GAS6 functions as a physiologic antiinflammatory agent produced by resting EC and depleted when proinflammatory stimuli turn on the proadhesive machinery of EC.


2015 ◽  
Vol 29 (S1) ◽  
Author(s):  
Mark Cunningham ◽  
Jessica Faulkner ◽  
Lorena Amaral ◽  
Denise Cornelius ◽  
Robert Kramer ◽  
...  

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