Prolonged exposure to high insulin impairs the endothelial PI3-kinase/Akt/nitric oxide signalling

2009 ◽  
Vol 101 (02) ◽  
pp. 345-350 ◽  
Author(s):  
Rosalinda Madonna ◽  
Raffaele De Caterina
Keyword(s):  
Nitric Oxide ◽  
Prolonged Exposure ◽  
Insulin Signalling ◽  
Umbilical Vein ◽  
Surface Expression ◽  
No Production ◽  
Insulin Effect ◽  
The Metabolic Syndrome ◽  
High Insulin

SummaryHyperinsulinemia predicts future cardiovascular events, but may also contribute to atherosclerosis. We therefore studied the consequences of prolonged insulin treatment of human umbilical vein endothelial cells (HUVEC) on the phosphatidylinositol-3‘-kinase(PI3K)/Akt/nitric oxide(NO)-dependent insulin signaling, together with the expression of the pro-atherogenic molecule vascular cell adhesion molecule (VCAM)-1. HUVEC were incubated with insulin (10–11 to 10–7 M) in short- (30 min) and long-term (24 h to 3 days) incubations. In short-term incubations, insulin did not affect constitutive Akt and eNOS at any concentration, but significantly increased their active phosphorylated forms, and NO production. In long-term incubations, however, such insulin effects on the phosphorylated forms, as well as NO production, were attenuated, promoting an effect of insulin also at concentrations otherwise ineffective. Such effects were accompanied by a boosting of insulin effect on VCAM-1 surface expression. In contrast, under similar conditions, insulin did not exert any significant effect on the surface expression of ICAM-1 and E-selectin. Therefore, prolonged exposure of HUVEC to high insulin levels induces a downregulation of the PI3K/Akt/eNOS axis. Such impairment of insulin signalling in states of prolonged hyperinsulinemia pontially contributes to detrimental effects on atherogenesis in insulin resistance states, such as the metabolic syndrome and type 2 diabetes.

scholarly journals In Vitro Study of Nitric Oxide Metabolites Effects on Human Hydatid ofEchinococcus granulosus

2009 ◽  
Vol 2009 ◽  
pp. 1-7 ◽  
Author(s):  
Razika Zeghir-Bouteldja ◽  
Manel Amri ◽  
Saliha Aitaissa ◽  
Samia Bouaziz ◽  
Dalila Mezioug ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Hydatid Cyst ◽  
Echinococcus Granulosus ◽  
In Vitro Study ◽  
No Production ◽  
In Vitro Effects ◽  
Nitric Oxide Metabolites

Hydatidosis is characterized by the long-term coexistence of larvaEchinococcus granulosusand its host without effective rejection. Previous studies demonstrated nitric oxide (NO) production (in vivo and in vitro) during hydatidosis. In this study, we investigated the direct in vitro effects of NO species: nitrite (NO2−), nitrate (NO3−) and peroxynitrite (ONOO−) on protoscolices (PSCs) viability and hydatid cyst layers integrity for 24 hours and 48 hours. Our results showed protoscolicidal activity ofNO2−andONOO−24 hours and 3 hours after treatment with 320 μM and 80 μM respectively. Degenerative effects were observed on germinal and laminated layers. The comparison of the in vitro effects of NO species on the PSCs viability indicated thatONOO−is more cytotoxic thanNO2−. In contrast,NO3−has no effect. These results suggest possible involvement ofNO2−andONOO−in antihydatic action and point the efficacy of these metabolites as scolicidal agents.

scholarly journals Cilostazol Induces eNOS and TM Expression via Activation with Sirtuin 1/Krüppel-like Factor 2 Pathway in Endothelial Cells

2021 ◽  
Vol 22 (19) ◽  
pp. 10287
Author(s):  
Chih-Hsien Wu ◽  
Yi-Lin Chiu ◽  
Chung-Yueh Hsieh ◽  
Guo-Shiang Tsung ◽  
Lian-Shan Wu ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Endothelial Cells ◽  
Endothelial Nitric Oxide Synthase ◽  
Umbilical Vein ◽  
Sirtuin 1 ◽  
No Production ◽  
Beneficial Effects ◽  
Umbilical Vein Endothelial Cells ◽  
Oxide Synthase ◽  
Endothelial Nitric Oxide

Cilostazol was suggested to be beneficial to retard in-stent atherosclerosis and prevent stent thrombosis. However, the mechanisms responsible for the beneficial effects of cilostazol are not fully understood. In this study, we attempted to verify the mechanism of the antithrombotic effect of cilostazol. Human umbilical vein endothelial cells (HUVECs) were cultured with various concentrations of cilostazol to verify its impact on endothelial cells. KLF2, silent information regulator transcript-1 (SIRT1), endothelial nitric oxide synthase (eNOS), and endothelial thrombomodulin (TM) expression levels were examined. We found cilostazol significantly activated KLF2 expression and KLF2-related endothelial function, including eNOS activation, Nitric oxide (NO) production, and TM secretion. The activation was regulated by SIRT1, which was also stimulated by cilostazol. These findings suggest that cilostazol may be capable of an antithrombotic and vasculoprotective effect in endothelial cells.

Endothelial cell function alteration after Junin virus infection

2003 ◽  
Vol 90 (08) ◽  
pp. 326-334 ◽  
Author(s):  
Ricardo Gomez ◽  
Roberto Pozner ◽  
Maria Lazzari ◽  
Lina D’Atri ◽  
Soledad Negrotto ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Endothelial Cell ◽  
Cell Function ◽  
Umbilical Vein ◽  
Hemorrhagic Fever ◽  
No Production ◽  
Epidemic Disease ◽  
Endothelial Cell Function ◽  
Junin Virus ◽  
Junín Virus

SummaryHematologic involvement is the main feature of Argentine hemorrhagic fever (AHF), an endemo-epidemic disease caused by Junin virus (JV). Since endothelial dysfunction could play a role in AHF-altered hemostasis, we studied human umbilical vein endothelial cell (HUVEC) infection with a virulent (JVv) and a non-virulent (JVa) JV strain. Cells were infected by the two JV variants with no detectable apoptosis or cytopathic effect. Both viral variants up-regulated ICAM-1 and VCAM-1 levels, while von Willebrand factor (VWF) production was decreased. Prostacyclin (PGI2) release and decay accelerating factor (DAF) expression were greater in JVv- than in JVa-infected or control cells. Furthermore, nitric oxide (NO) production and endothelial nitric oxide synthase (eNOS) expression was only raised in JVv-infected supernatants. Significant NO and PGI2 values were also detected in AHF patient sera.These data demonstrate that endothelial cell responses are triggered subsequently by JV infection, suggesting that such alterations play a major role in the pathogenesis of AHF and perhaps in other viral-induced hemorrhagic diseases.

scholarly journals Anti-Hypertensive Activity of Novel Peptides Identified from Olive Flounder (Paralichthys olivaceus) Surimi

Foods ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 647
Author(s):  
Jae-Young Oh ◽  
Jun-Geon Je ◽  
Hyo-Geun Lee ◽  
Eun-A Kim ◽  
Sang In Kang ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Umbilical Vein ◽  
Paralichthys Olivaceus ◽  
Health Benefits ◽  
Olive Flounder ◽  
Antihypertensive Activity ◽  
No Production ◽  
Food Ingredient ◽  
Food Ingredients ◽  
Olive Flounder Paralichthys Olivaceus

There is a growing interest in the health benefits of functional foods. A benefit that has been long sought is the control of hypertension through dietary approaches. Hypertension has been implicated as a risk factor for cardiovascular disease and is therefore of clinical significance. Here, we aim to demonstrate the antihypertensive activity of novel peptides derived from surimi, a functional food ingredient made from refined fish myofibrillar proteins. Three peptides, Ile-Val-Asp-Arg (IVDR), Trp-Tyr-Lys (WYK), and Val-Ala-Ser-Val-Ile (VASVI), were isolated from surimi made from the olive flounder (Paralichthys olivaceus). Our results show that IVDR, WYK, and VASVI exhibited high Angiotensin I-converting Enzyme (ACE) inhibition activity. These peptides are also shown to increase phosphorylation of protein kinase B (Akt) and endothelial nitric oxide synthase (eNOS), and significantly promote nitric oxide (NO) production in human umbilical vein endothelial cells. Oral administration of the peptides decreased blood pressure in spontaneously hypertensive rats (SHRs), thereby confirming that the peptides derived from surimi perform antihypertensive activity via the Akt/eNOS pathway. These results indicate that surimi made from P. olivaceus contains novel antihypertensive peptides that could be used to enhance the health benefits of food ingredients.

Endothelial nitric oxide production during in vitro simulation of external limb compression

2002 ◽  
Vol 282 (6) ◽  
pp. H2066-H2075 ◽  
Author(s):  
Guohao Dai ◽  
Olga Tsukurov ◽  
Michael Chen ◽  
Jonathan P. Gertler ◽  
Roger D. Kamm
Keyword(s):  
Nitric Oxide ◽  
Mrna Expression ◽  
Umbilical Vein ◽  
Control Group ◽  
No Production ◽  
Vein Thrombosis ◽  
Enos Mrna ◽  
Umbilical Vein Endothelial Cells ◽  
Endothelial Nitric Oxide

External pneumatic compression (EPC) is effective in preventing deep vein thrombosis (DVT) and is thought to alter endothelial thromboresistant properties. We investigated the effect of EPC on changes in nitric oxide (NO), a critical mediator in the regulation of vasomotor and platelet function. An in vitro cell culture system was developed to simulate flow and vessel collapse conditions under EPC. Human umbilical vein endothelial cells were cultured and subjected to tube compression (C), pulsatile flow (F), or a combination of the two (FC). NO production and endothelial nitric oxide synthase (eNOS) mRNA expression were measured. The data demonstrate that in the F and FC groups, there is a rapid release of NO followed by a sustained increase. NO production levels in the F and FC groups were almost identical, whereas the C group produced the same low amount of NO as the control group. Conditions F and FC also upregulate eNOS mRNA expression by a factor of 2.08 ± 0.25 and 2.11 ± 0.21, respectively, at 6 h. Experiments with different modes of EPC show that NO production and eNOS mRNA expression respond to different time cycles of compression. These results implicate enhanced NO release as a potentially important factor in the prevention of DVT.

scholarly journals Salidroside Stimulates Mitochondrial Biogenesis and Protects against H2O2-Induced Endothelial Dysfunction

2014 ◽  
Vol 2014 ◽  
pp. 1-13 ◽  
Author(s):  
Shasha Xing ◽  
Xiaoyan Yang ◽  
Wenjing Li ◽  
Fang Bian ◽  
Dan Wu ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Endothelial Cells ◽  
Transcription Factor ◽  
Endothelial Dysfunction ◽  
Mitochondrial Biogenesis ◽  
Umbilical Vein ◽  
Adenosine Monophosphate ◽  
No Production ◽  
Peroxisome Proliferator ◽  
Atp Production

Salidroside (SAL) is an active component ofRhodiola roseawith documented antioxidative properties. The purpose of this study is to explore the mechanism of the protective effect of SAL on hydrogen peroxide- (H2O2-) induced endothelial dysfunction. Pretreatment of the human umbilical vein endothelial cells (HUVECs) with SAL significantly reduced the cytotoxicity brought by H2O2. Functional studies on the rat aortas found that SAL rescued the endothelium-dependent relaxation and reduced superoxide anion (O2∙-) production induced by H2O2. Meanwhile, SAL pretreatment inhibited H2O2-induced nitric oxide (NO) production. The underlying mechanisms involve the inhibition of H2O2-induced activation of endothelial nitric oxide synthase (eNOS), adenosine monophosphate-activated protein kinase (AMPK), and Akt, as well as the redox sensitive transcription factor, NF-kappa B (NF-κB). SAL also increased mitochondrial mass and upregulated the mitochondrial biogenesis factors, peroxisome proliferator-activated receptor gamma-coactivator-1alpha (PGC-1α), and mitochondrial transcription factor A (TFAM) in the endothelial cells. H2O2-induced mitochondrial dysfunction, as demonstrated by reduced mitochondrial membrane potential (Δψm) and ATP production, was rescued by SAL pretreatment. Taken together, these findings implicate that SAL could protect endothelium against H2O2-induced injury via promoting mitochondrial biogenesis and function, thus preventing the overactivation of oxidative stress-related downstream signaling pathways.

Small- and intermediate-conductance Ca2+-activated K+ channels directly control agonist-evoked nitric oxide synthesis in human vascular endothelial cells

2007 ◽  
Vol 293 (1) ◽  
pp. C458-C467 ◽  
Author(s):  
Jian-Zhong Sheng ◽  
Andrew P. Braun
Keyword(s):  
Nitric Oxide ◽  
Endothelial Cells ◽  
Vascular Endothelial Cells ◽  
Umbilical Vein ◽  
Early Event ◽  
No Production ◽  
Primary Role ◽  
Membrane Hyperpolarization ◽  
Intracellular Ca ◽  
Umbilical Vein Endothelial Cells

The contribution of small-conductance (SKCa) and intermediate-conductance Ca2+-activated K+ (IKCa) channels to the generation of nitric oxide (NO) by Ca2+-mobilizing stimuli was investigated in human umbilical vein endothelial cells (HUVECs) by combining single-cell microfluorimetry with perforated patch-clamp recordings to monitor agonist-evoked NO synthesis, cytosolic Ca2+ transients, and membrane hyperpolarization in real time. ATP or histamine evoked reproducible elevations in NO synthesis and cytosolic Ca2+, as judged by 4-amino-5-methylamino-2′,7′-difluorofluorescein (DAF-FM) and fluo-3 fluorescence, respectively, that were tightly associated with membrane hyperpolarizations. Whereas evoked NO synthesis was unaffected by either tetraethylammonium (10 mmol/l) or BaCl2 (50 μmol/l) + ouabain (100 μmol/l), depleting intracellular Ca2+ stores by thapsigargin or removing external Ca2+ inhibited NO production, as did exposure to high (80 mmol/l) external KCl. Importantly, apamin and charybdotoxin (ChTx)/ triarylmethane (TRAM)-34, selective blockers SKCa and IKCa channels, respectively, abolished both stimulated NO synthesis and membrane hyperpolarization and decreased evoked Ca2+ transients. Apamin and TRAM-34 also inhibited an agonist-induced outwardly rectifying current characteristic of SKCa and IKCa channels. Under voltage-clamp control, we further observed that the magnitude of agonist-induced NO production varied directly with the degree of membrane hyperpolarization. Mechanistically, our data indicate that SKCa and IKCa channel-mediated hyperpolarization represents a critical early event in agonist-evoked NO production by regulating the influx of Ca2+ responsible for endothelial NO synthase activation. Moreover, it appears that the primary role of agonist-induced release of intracellular Ca2+ stores is to trigger the opening of both KCa channels along with Ca2+ entry channels at the plasma membrane. Finally, the observed inhibition of stimulated NO synthesis by apamin and ChTx/TRAM-34 demonstrates that SKCa and IKCa channels are essential for NO-mediated vasorelaxation.

scholarly journals Programmed cell death 5 suppresses AKT-mediated cytoprotection of endothelium

2018 ◽  
Vol 115 (18) ◽  
pp. 4672-4677 ◽  
Author(s):  
Seung-Hyun Lee ◽  
Jaesung Seo ◽  
Soo-Yeon Park ◽  
Mi-Hyeon Jeong ◽  
Hyo-Kyoung Choi ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Cell Death ◽  
Programmed Cell Death ◽  
Umbilical Vein ◽  
Density Lipoprotein ◽  
No Production ◽  
Dependent Signal ◽  
Programmed Cell Death 5 ◽  
Umbilical Vein Endothelial Cells ◽  
Endothelial Nitric Oxide

Programmed cell death 5 (PDCD5) has been associated with human cancers as a regulator of cell death; however, the role of PDCD5 in the endothelium has not been revealed. Thus, we investigated whether PDCD5 regulates protein kinase B (PKB/AKT)-endothelial nitric oxide synthase (eNOS)–dependent signal transduction in the endothelium and affects atherosclerosis. Endothelial-specific PDCD5 knockout mice showed significantly reduced vascular remodeling compared with wild-type (WT) mice after partial carotid ligation. WT PDCD5 competitively inhibited interaction between histone deacetylase 3 (HDAC3) and AKT, but PDCD5L6R, an HDAC3-binding–deficient mutant, did not. Knockdown of PDCD5 accelerated HDAC3–AKT interaction, AKT and eNOS phosphorylation, and nitric oxide (NO) production in human umbilical vein endothelial cells. Moreover, we found that serum PDCD5 levels reflect endothelial NO production and are correlated with diabetes mellitus, high-density lipoprotein cholesterol, and coronary calcium in human samples obtained from the cardiovascular high-risk cohort. Therefore, we conclude that PDCD5 is associated with endothelial dysfunction and may be a novel therapeutic target in atherosclerosis.

VEGF upregulates ecNOS message, protein, and NO production in human endothelial cells

1998 ◽  
Vol 274 (3) ◽  
pp. H1054-H1058 ◽  
Author(s):  
John D. Hood ◽  
Cynthia J. Meininger ◽  
Marina Ziche ◽  
Harris J. Granger
Keyword(s):  
Nitric Oxide ◽  
Endothelial Cells ◽  
Umbilical Vein ◽  
Northern Blotting ◽  
No Production ◽  
Vascular Endothelial ◽  
Umbilical Vein Endothelial Cells ◽  
Oxide Synthase ◽  
Endothelial Growth Factor ◽  
Stimulation Of

Vascular endothelial growth factor (VEGF) is an endothelium-specific secreted protein that potently stimulates vasodilation, microvascular hyperpermeability, and angiogenesis. Nitric oxide (NO) is also reported to modulate vascular tone, permeability, and capillary growth. Therefore, we hypothesized that VEGF might regulate endothelial production of NO. The production of nitrogen oxides by human umbilical vein endothelial cells (HUVECs) was measured after 1, 12, 24, and 48 h of incubation with VEGF. VEGF treatment resulted in both an acute (1 h) and chronic (>24 h) stimulation of NO production. Furthermore, Western and Northern blotting revealed a VEGF-elicited, dose-dependent increase in the cellular content of endothelial cell nitric oxide synthase (ecNOS) message and protein that may account for the chronic upregulation of NO production elicited by VEGF. Finally, endothelial cells pretreated with VEGF for 24 h and subsequently exposed to A-23187 for 1 h produced NO at approximately twice the rate of cells that were not pretreated with VEGF. We conclude that VEGF upregulates ecNOS enzyme and elicits a biphasic stimulation of endothelial NO production.

scholarly journals AICAR Protects Vascular Endothelial Cells from Oxidative Injury Induced by the Long-Term Palmitate Excess

2021 ◽  
Vol 23 (1) ◽  
pp. 211
Author(s):  
Mikhail V. Samsonov ◽  
Nikita V. Podkuychenko ◽  
Asker Y. Khapchaev ◽  
Eugene E. Efremov ◽  
Elena V. Yanushevskaya ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Insulin Signaling ◽  
Umbilical Vein ◽  
Blood Levels ◽  
Ros Generation ◽  
No Production ◽  
Vascular Endothelial ◽  
Long Term Effects

Hyperlipidemia manifested by high blood levels of free fatty acids (FFA) and lipoprotein triglycerides is critical for the progression of type 2 diabetes (T2D) and its cardiovascular complications via vascular endothelial dysfunction. However, attempts to assess high FFA effects in endothelial culture often result in early cell apoptosis that poorly recapitulates a much slower pace of vascular deterioration in vivo and does not provide for the longer-term studies of endothelial lipotoxicity in vitro. Here, we report that palmitate (PA), a typical FFA, does not impair, by itself, endothelial barrier and insulin signaling in human umbilical vein endothelial cells (HUVEC), but increases NO release, reactive oxygen species (ROS) generation, and protein labeling by malondialdehyde (MDA) hallmarking oxidative stress and increased lipid peroxidation. This PA-induced stress eventually resulted in the loss of cell viability coincident with loss of insulin signaling. Supplementation with 5-aminoimidazole-4-carboxamide-riboside (AICAR) increased endothelial AMP-activated protein kinase (AMPK) activity, supported insulin signaling, and prevented the PA-induced increases in NO, ROS, and MDA, thus allowing to maintain HUVEC viability and barrier, and providing the means to study the long-term effects of high FFA levels in endothelial cultures. An upgraded cell-based model reproduces FFA-induced insulin resistance by demonstrating decreased NO production by vascular endothelium.

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