scholarly journals Application of Oxidative Stress to a Tissue-Engineered Vascular Aging Model Induces Endothelial Cell Senescence and Activation

Cells ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 1292
Author(s):  
Ellen E. Salmon ◽  
Jason J. Breithaupt ◽  
George A. Truskey

Clinical studies have established a connection between oxidative stress, aging, and atherogenesis. These factors contribute to senescence and inflammation in the endothelium and significant reductions in endothelium-dependent vasoreactivity in aged patients. Tissue-engineered blood vessels (TEBVs) recapitulate the structure and function of arteries and arterioles in vitro. We developed a TEBV model for vascular senescence and examined the relative influence of endothelial cell and smooth muscle cell senescence on vasoreactivity. Senescence was induced in 2D endothelial cell cultures and TEBVs by exposure to 100 µM H2O2 for one week to model chronic oxidative stress. H2O2 treatment significantly increased senescence in endothelial cells and mural cells, human neonatal dermal fibroblasts (hNDFs), as measured by increased p21 levels and reduced NOS3 expression. Although H2O2 treatment induced senescence in both the endothelial cells (ECs) and hNDFs, the functional effects on the vasculature were endothelium specific. Expression of the leukocyte adhesion molecule vascular cell adhesion molecule 1 (VCAM-1) was increased in the ECs, and endothelium-dependent vasodilation decreased. Vasoconstriction and endothelium-independent vasodilation were preserved despite mural cell senescence. The results suggest that the functional effects of vascular cell senescence are dominated by the endothelium.

2014 ◽  
Vol 2014 ◽  
pp. 1-13 ◽  
Author(s):  
Rong Liu ◽  
Hua Liu ◽  
Yonju Ha ◽  
Ronald G. Tilton ◽  
Wenbo Zhang

Accumulating evidence has shown that diabetes accelerates aging and endothelial cell senescence is involved in the pathogenesis of diabetic vascular complications, including diabetic retinopathy. Oxidative stress is recognized as a key factor in the induction of endothelial senescence and diabetic retinopathy. However, specific mechanisms involved in oxidative stress-induced endothelial senescence have not been elucidated. We hypothesized that Sirt6, which is a nuclear, chromatin-bound protein critically involved in many pathophysiologic processes such as aging and inflammation, may have a role in oxidative stress-induced vascular cell senescence. Measurement of Sirt6 expression in human endothelial cells revealed that H2O2treatment significantly reduced Sirt6 protein. The loss of Sirt6 was associated with an induction of a senescence phenotype in endothelial cells, including decreased cell growth, proliferation and angiogenic ability, and increased expression of senescence-associatedβ-galactosidase activity. Additionally, H2O2treatment reduced eNOS expression, enhanced p21 expression, and dephosphorylated (activated) retinoblastoma (Rb) protein. All of these alternations were attenuated by overexpression of Sirt6, while partial knockdown of Sirt6 expression by siRNA mimicked the effect of H2O2. In conclusion, these results suggest that Sirt6 is a critical regulator of endothelial senescence and oxidative stress-induced downregulation of Sirt6 is likely involved in the pathogenesis of diabetic retinopathy.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
T. Girão-Silva ◽  
M. H. Fonseca-Alaniz ◽  
J. C. Ribeiro-Silva ◽  
J. Lee ◽  
N. P. Patil ◽  
...  

AbstractThe rate of the remodeling of the arterialized saphenous vein conduit limits the outcomes of coronary artery bypass graft surgery (CABG), which may be influenced by endothelial dysfunction. We tested the hypothesis that high stretch (HS) induces human saphenous vein endothelial cell (hSVEC) dysfunction and examined candidate underlying mechanisms. Our results showed that in vitro HS reduces NO bioavailability, increases inflammatory adhesion molecule expression (E-selectin and VCAM1) and THP-1 cell adhesion. HS decreases F-actin in hSVECs, but not in human arterial endothelial cells, and is accompanied by G-actin and cofilin’s nuclear shuttling and increased reactive oxidative species (ROS). Pre-treatment with the broad-acting antioxidant N-acetylcysteine (NAC) supported this observation and diminished stretch-induced actin remodeling and inflammatory adhesive molecule expression. Altogether, we provide evidence that increased oxidative stress and actin cytoskeleton remodeling play a role in HS-induced saphenous vein endothelial cell dysfunction, which may contribute to predisposing saphenous vein graft to failure.


1991 ◽  
Vol 114 (3) ◽  
pp. 557-565 ◽  
Author(s):  
K Miyake ◽  
K Medina ◽  
K Ishihara ◽  
M Kimoto ◽  
R Auerbach ◽  
...  

Two new mAbs (M/K-1 and M/K-2) define an adhesion molecule expressed on stromal cell clones derived from murine bone marrow. The protein is similar in size to a human endothelial cell adhesion molecule known as VCAM-1 or INCAM110. VCAM-1 is expressed on endothelial cells in inflammatory sites and recognized by the integrin VLA-4 expressed on lymphocytes and monocytes. The new stromal cell molecule is a candidate ligand for the VLA-4 expressed on immature B lineage lymphocytes and a possible homologue of human VCAM-1. We now report additional similarities in the distribution, structure, and function of these proteins. The M/K antibodies detected large cells in normal bone marrow, as well as rare cells in other tissues. The antigen was constitutively expressed and functioned as a cell adhesion molecule on cultured murine endothelial cells. It correlated with the presence of mRNA which hybridized to a human VCAM-1 cDNA probe. Partial NH2 terminal amino acid sequencing of the murine protein revealed similarities to VCAM-1 and attachment of human lymphoma cells to murine endothelial cell lines was inhibited by the M/K antibodies. All of these observations suggest that the murine and human cell adhesion proteins may be related. The antibodies selectively interfered with B lymphocyte formation when included in long term bone marrow cultures. Moreover, they caused rapid detachment of lymphocytes from the adherent layer when added to preestablished cultures. The VCAM-like cell adhesion molecule on stromal cells and VLA-4 on lymphocyte precursors may both be important for B lymphocyte formation.


2005 ◽  
Vol 73 (6) ◽  
pp. 3271-3277 ◽  
Author(s):  
Nicola K. Viebig ◽  
Ulrich Wulbrand ◽  
Reinhold Förster ◽  
Katherine T. Andrews ◽  
Michael Lanzer ◽  
...  

ABSTRACT Cytoadherence of Plasmodium falciparum-infected erythrocytes (PRBC) to endothelial cells causes severe clinical disease, presumably as a of result perfusion failure and tissue hypoxia. Cytoadherence to endothelial cells is increased by endothelial cell activation, which is believed to occur in a paracrine fashion by mediators such as tumor necrosis factor alpha (TNF-α) released from macrophages that initially recognize PRBC. Here we provide evidence that PRBC directly stimulate human endothelial cells in the absence of macrophages, leading to increased expression of adhesion-promoting molecules, such as intercellular adhesion molecule 1. Endothelial cell stimulation by PRBC required direct physical contact for a short time (30 to 60 min) and was correlated with parasitemia. Gene expression profiling of endothelial cells stimulated by PRBC revealed increased expression levels of chemokine and adhesion molecule genes. PRBC-stimulated endothelial cells especially showed increased expression of molecules involved in parasite adhesion but failed to express molecules promoting leukocyte adhesion, such as E-selectin and vascular cell adhesion molecule 1, even after challenge with TNF-α. Collectively, our data suggest that stimulation of endothelial cells by PRBC may have two effects: prevention of parasite clearance through increased cytoadherence and attenuation of leukocyte binding to endothelial cells, thereby preventing deleterious immune reactivity.


1992 ◽  
Vol 176 (6) ◽  
pp. 1583-1593 ◽  
Author(s):  
A S Neish ◽  
A J Williams ◽  
H J Palmer ◽  
M Z Whitley ◽  
T Collins

The vascular cell adhesion molecule 1 (VCAM-1) is a 110-kD member of the immunoglobulin gene superfamily expressed on the surface of interleukin 1 beta- or tumor necrosis factor alpha (TNF)-stimulated endothelial cells. The cell surface protein functions as an inducible adhesion receptor for circulating mononuclear leukocytes and some tumor cells. We have previously characterized the genomic organization of the VCAM1 gene and described its chromosomal localization. In this report, the promoter of the VCAM1 gene is characterized. New transcription of the VCAM1 gene occurred when endothelial cells were treated with TNF. Fusion plasmids containing the 5' flanking sequence of the VCAM1 gene and the chloramphenicol acetyltransferase reporter gene were used to identify cis-acting sequences that direct the cytokine-induced transcription. When transfected into bovine aortic endothelial cells, constructs containing 755 bp of the 5' flanking sequence were induced by TNF. Within the cytokine-responsive region of the core promoter were functional NF-kappa B and GATA elements. Upstream of the core promoter, the VCAM1 5' flanking sequence contained a negative regulatory activity. NF-kappa B-mediated activation of VCAM1 gene expression may lead to endothelial expression of a mononuclear leukocyte adhesion molecule associated with initial events in the development of an atherosclerotic lesion.


Circulation ◽  
2007 ◽  
Vol 116 (suppl_16) ◽  
Author(s):  
Christopher J Dougherty ◽  
Howard Prentice ◽  
Kathleen Dorey ◽  
Keith A Webster ◽  
Janet C Blanks

Loss of pericytes is a critical event early in the progression of microvascular dysfunction in diabetic retinopathy. Pericyte loss may be linked to high glucose mediated reactive oxygen species generation, blocking N-cadherin trafficking to the endothelial cell surface preventing pericyte recruitment and vessel stabilization. Hydrogen peroxide has been identified as a major free radical produced during high glucose exposure in endothelial cells. The goal of this research is to determine if tissue-specific hypoxia-regulated expression of a mitochondria-targeted catalase can prevent or limit RF/6A microvascular endothelial cell apoptosis and decrease vascular permeability by limiting cellular oxidative stress. For the development of tissue-specific and hypoxia-enhanced expression vectors, promoters were constructed with nine tandem combinations of HREs. This 9x HRE oligomer enhancer was inserted together into a pGL3 firefly luciferase plasmid with the Tie2( short ) promoter for endothelial-specific expression. The 9xHRE-Tie2( sh ) promoter construct was highly selective for RF/6A cells producing a basal amount of mitochondria-targeted catalase equivalent to the Tie2( short ) promoter alone. In response to hypoxia ( pO 2 = 1% ), the 9xHRE-Tie2( short ) promoter showed a 21-fold hypoxia-inducible activation similar in strength to the CMV promoter , measured by dual luciferase assay. The hybrid promoters were incorporated into a replication deficient AAV delivery system for apoptosis and cell culture based endothelial permeability assays. In preliminary assays using RF/6A microvascular endothelial cells, apoptosis was reduced by 58% and permeability was reduced by 46%. The results suggest that mitochondria-targeted catalase protects RF/6A microvascular endothelial cells from apoptosis and reduces endothelial permeability in a high-glucose, low-oxygen environment.


1993 ◽  
Vol 264 (3) ◽  
pp. C715-C722 ◽  
Author(s):  
D. Lu ◽  
N. Maulik ◽  
I. I. Moraru ◽  
D. L. Kreutzer ◽  
D. K. Das

Cellular organisms respond at the cellular and molecular level when confronted with sudden changes in environment, and molecular adaptation represents the ability of the cells to acclimate themselves to their new environment. In this study we examined the response of bovine vascular endothelial cells (VEC) to the oxidative stress by exposing the cultured cells to two different concentrations of H2O2, 0.04 or 0.08 mM, for 18-24 h. H2O2-exposed VEC displayed good viability (85-90% for 0.04 mM H2O2; 75-80% for 0.08 mM H2O2) and exhibited normal morphology. H2O2 treatment of the VEC was associated with the expression of a number of new proteins, as demonstrated by two-dimensional gel electrophoresis of total cell lysate. Cells exposed to 0.04 mM H2O2 expressed 25 new proteins, whereas 19 newly expressed proteins were detected when the cells were exposed to 0.08 mM H2O2. Western blot analysis of H2O2-treated VEC using specific antibodies to heat-shock proteins (HSP) identified one of these proteins as a member of the HSP 70 family. In addition, H2O2 induced an increase in antioxidative enzyme activities in the VEC, including superoxide dismutase, catalase, and glutathione peroxidase. Moreover, these changes were a truly adaptive phenomenon because challenging the VEC with brief exposure to toxic levels of H2O2 (1 mM for 30 min) showed increased viability (by Trypan blue exclusion test) and decreased injury (by lactate dehydrogenase supernatant-to-cellular ratio determination) in adapted cells (preexposed to 0.04 or 0.08 mM H2O2) compared with control cells.(ABSTRACT TRUNCATED AT 250 WORDS)


Sign in / Sign up

Export Citation Format

Share Document