Methylglyoxal Induces Endothelial Dysfunction via Stunning

Elevated levels of methylglyoxal (MG) and its associated post-translational modifications have been reported to be associated with progression and development of numerous pathological conditions. Despite such extensive evidence, it still remains unclear what the specific effects of MG are other than that induction of cytotoxicity. Here we evaluated the effects of MG in cardiac endothelial cells in vitro. We found that MG leads to a non-proliferative state and endothelial dysfunction, which is reversible as MG-H1, a major post-translational modification induced by MG, is turned over by lysosomal degradation. MG-induced cellular stunning/paralysis describes a new hallmark for cellular dysfunction which could lead to alterations in tissue homeostasis as well as cell-to-cell interactions, thereby contributing to the pathogenesis of diseases.

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Generation of a Novel In Vitro Model to Study Endothelial Dysfunction from Atherothrombotic Specimens

Cardiovascular Drugs and Therapy ◽

10.1007/s10557-021-07151-9 ◽

2021 ◽

Author(s):

Susan Gallogly ◽

Takeshi Fujisawa ◽

John D. Hung ◽

Mairi Brittan ◽

Elizabeth M. Skinner ◽

...

Keyword(s):

Endothelial Cells ◽

Endothelial Dysfunction ◽

In Vitro Model ◽

Umbilical Vein ◽

Coronary Syndrome ◽

Coronary Endothelial Cells ◽

Vitro Model ◽

Umbilical Vein Endothelial Cells

Abstract Purpose Endothelial dysfunction is central to the pathogenesis of acute coronary syndrome. The study of diseased endothelium is very challenging due to inherent difficulties in isolating endothelial cells from the coronary vascular bed. We sought to isolate and characterise coronary endothelial cells from patients undergoing thrombectomy for myocardial infarction to develop a patient-specific in vitro model of endothelial dysfunction. Methods In a prospective cohort study, 49 patients underwent percutaneous coronary intervention with thrombus aspiration. Specimens were cultured, and coronary endothelial outgrowth (CEO) cells were isolated. CEO cells, endothelial cells isolated from peripheral blood, explanted coronary arteries, and umbilical veins were phenotyped and assessed functionally in vitro and in vivo. Results CEO cells were obtained from 27/37 (73%) atherothrombotic specimens and gave rise to cells with cobblestone morphology expressing CD146 (94 ± 6%), CD31 (87 ± 14%), and von Willebrand factor (100 ± 1%). Proliferation of CEO cells was impaired compared to both coronary artery and umbilical vein endothelial cells (population doubling time, 2.5 ± 1.0 versus 1.6 ± 0.3 and 1.2 ± 0.3 days, respectively). Cell migration was also reduced compared to umbilical vein endothelial cells (29 ± 20% versus 85±19%). Importantly, unlike control endothelial cells, dysfunctional CEO cells did not incorporate into new vessels or promote angiogenesis in vivo. Conclusions CEO cells can be reliably isolated and cultured from thrombectomy specimens in patients with acute coronary syndrome. Compared to controls, patient-derived coronary endothelial cells had impaired capacity to proliferate, migrate, and contribute to angiogenesis. CEO cells could be used to identify novel therapeutic targets to enhance endothelial function and prevent acute coronary syndromes.

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Hyperglycaemia up-regulates placental growth factor (PlGF) expression and secretion in endothelial cells via suppression of PI3 kinase-Akt signalling and activation of FOXO1

Scientific Reports ◽

10.1038/s41598-021-95511-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Samir Sissaoui ◽

Stuart Egginton ◽

Ling Ting ◽

Asif Ahmed ◽

Peter W. Hewett

Keyword(s):

Endothelial Cells ◽

Growth Factor ◽

Endothelial Dysfunction ◽

Akt Activation ◽

Forkhead Box ◽

Pi3k Activity ◽

Binding Sequence

AbstractPlacenta growth factor (PlGF) is a pro-inflammatory angiogenic mediator that promotes many pathologies including diabetic complications and atherosclerosis. Widespread endothelial dysfunction precedes the onset of these conditions. As very little is known of the mechanism(s) controlling PlGF expression in pathology we investigated the role of hyperglycaemia in the regulation of PlGF production in endothelial cells. Hyperglycaemia stimulated PlGF secretion in cultured primary endothelial cells, which was suppressed by IGF-1-mediated PI3K/Akt activation. Inhibition of PI3K activity resulted in significant PlGF mRNA up-regulation and protein secretion. Similarly, loss or inhibition of Akt activity significantly increased basal PlGF expression and prevented any further PlGF secretion in hyperglycaemia. Conversely, constitutive Akt activation blocked PlGF secretion irrespective of upstream PI3K activity demonstrating that Akt is a central regulator of PlGF expression. Knock-down of the Forkhead box O-1 (FOXO1) transcription factor, which is negatively regulated by Akt, suppressed both basal and hyperglycaemia-induced PlGF secretion, whilst FOXO1 gain-of-function up-regulated PlGF in vitro and in vivo. FOXO1 association to a FOXO binding sequence identified in the PlGF promoter also increased in hyperglycaemia. This study identifies the PI3K/Akt/FOXO1 signalling axis as a key regulator of PlGF expression and unifying pathway by which PlGF may contribute to common disorders characterised by endothelial dysfunction, providing a target for therapy.

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Antibodies to kidney endothelial cells contribute to a “leaky” glomerular barrier in patients with chronic kidney diseases

AJP Renal Physiology ◽

10.1152/ajprenal.00250.2011 ◽

2012 ◽

Vol 302 (7) ◽

pp. F884-F894 ◽

Cited By ~ 13

Author(s):

Nidia Maritza Hernandez ◽

Anna Casselbrant ◽

Meghnad Joshi ◽

Bengt R. Johansson ◽

Suchitra Sumitran-Holgersson

Keyword(s):

Endothelial Cells ◽

Endothelial Cell ◽

Endothelial Dysfunction ◽

Kidney Diseases ◽

Clinical Importance ◽

Human Kidney ◽

Cell Permeability ◽

Chronic Kidney Diseases ◽

Esrd Patients

Anti-endothelial cell antibodies (AECA) have been reported to cause endothelial dysfunction, but their clinical importance for tissue-specific endothelial cells is not clear. We hypothesized that AECA reactive with human kidney endothelial cells (HKEC) may cause renal endothelial dysfunction in patients with chronic kidney diseases. We report that a higher fraction (56%) of end-stage renal disease (ESRD) patients than healthy controls (5%) have AECA reactive against kidney endothelial cells ( P <0.001). The presence of antibodies was associated with female gender ( P < 0.001), systolic hypertension ( P < 0.01), and elevated TNF-α ( P < 0.05). These antibodies markedly decrease expression of both adherens and tight junction proteins VE-cadherin, claudin-1, and zonula occludens-1 and provoked a rapid increase in cytosolic free Ca2+and rearrangement of actin filaments in HKEC compared with controls. This was followed by an enhancement in protein flux and phosphorylation of VE-cadherin, events associated with augmented endothelial cell permeability. Additionally, kidney biopsies from ESRD patients with AECA but not controls demonstrated a marked decrease in adherens and tight junctions in glomerular endothelium, confirming our in vitro data. In summary, our data demonstrate a causal link between AECA and their capacity to induce alterations in glomerular vascular permeability.

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Diabetic Endothelial Cells Differentiated From Patient iPSCs Show Dysregulated Glycine Homeostasis and Senescence Associated Phenotypes

Frontiers in Cell and Developmental Biology ◽

10.3389/fcell.2021.667252 ◽

2021 ◽

Vol 9 ◽

Author(s):

Liping Su ◽

Xiaocen Kong ◽

Sze Jie Loo ◽

Yu Gao ◽

Jean-Paul Kovalik ◽

...

Keyword(s):

Endothelial Cells ◽

Endothelial Dysfunction ◽

Pluripotent Stem Cells ◽

Molecular Mechanisms ◽

Cell Transfer ◽

Angiogenic Potential ◽

Patients With Diabetes ◽

Induced Pluripotent

Induced pluripotent stem cells derived cells (iPSCs) not only can be used for personalized cell transfer therapy, but also can be used for modeling diseases for drug screening and discovery in vitro. Although prior studies have characterized the function of rodent iPSCs derived endothelial cells (ECs) in diabetes or metabolic syndrome, feature phenotypes are largely unknown in hiPSC-ECs from patients with diabetes. Here, we used hiPSC lines from patients with type 2 diabetes mellitus (T2DM) and differentiated them into ECs (dia-hiPSC-ECs). We found that dia-hiPSC-ECs had disrupted glycine homeostasis, increased senescence, and impaired mitochondrial function and angiogenic potential as compared with healthy hiPSC-ECs. These signature phenotypes will be helpful to establish dia-hiPSC-ECs as models of endothelial dysfunction for understanding molecular mechanisms of disease and for identifying and testing new targets for the treatment of endothelial dysfunction in diabetes.

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Endothelial Dysfunction in Fabry Disease Is Related to Glycocalyx Degradation

Frontiers in Immunology ◽

10.3389/fimmu.2021.789142 ◽

2021 ◽

Vol 12 ◽

Author(s):

Solvey Pollmann ◽

David Scharnetzki ◽

Dominique Manikowski ◽

Malte Lenders ◽

Eva Brand

Keyword(s):

Endothelial Cells ◽

Endothelial Dysfunction ◽

Endothelial Function ◽

Fabry Disease ◽

Specific Inhibitor ◽

Small Vessel ◽

Endothelial Glycocalyx ◽

Enzyme Replacement ◽

Anti Inflammatory

Fabry disease (FD) is an X-linked multisystemic lysosomal storage disease due to a deficiency of α-galactosidase A (GLA/AGAL). Progressive cellular accumulation of the AGAL substrate globotriaosylceramide (Gb3) leads to endothelial dysfunction. Here, we analyzed endothelial function in vivo and in vitro in an AGAL-deficient genetic background to identify the processes underlying this small vessel disease. Arterial stiffness and endothelial function was prospectively measured in five males carrying GLA variants (control) and 22 FD patients under therapy. AGAL-deficient endothelial cells (EA.hy926) and monocytes (THP1) were used to analyze endothelial glycocalyx structure, function, and underlying inflammatory signals. Glycocalyx thickness and small vessel function improved significantly over time (p<0.05) in patients treated with enzyme replacement therapy (ERT, n=16) and chaperones (n=6). AGAL-deficient endothelial cells showed reduced glycocalyx and increased monocyte adhesion (p<0.05). In addition, increased expression of angiopoietin-2, heparanase and NF-κB was detected (all p<0.05). Incubation of wild-type endothelial cells with pathological globotriaosylsphingosine concentrations resulted in comparable findings. Treatment of AGAL-deficient cells with recombinant AGAL (p<0.01), heparin (p<0.01), anti-inflammatory (p<0.001) and antioxidant drugs (p<0.05), and a specific inhibitor (razuprotafib) of angiopoietin-1 receptor (Tie2) (p<0.05) improved glycocalyx structure and endothelial function in vitro. We conclude that chronic inflammation, including the release of heparanases, appears to be responsible for the degradation of the endothelial glycocalyx and may explain the endothelial dysfunction in FD. This process is partially reversible by FD-specific and anti-inflammatory treatment, such as targeted protective Tie2 treatment.

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Corneal endothelial cell dysfunction: etiologies and management

Therapeutic Advances in Ophthalmology ◽

10.1177/2515841418815802 ◽

2018 ◽

Vol 10 ◽

pp. 251584141881580 ◽

Cited By ~ 13

Author(s):

Sepehr Feizi

Keyword(s):

Endothelial Cells ◽

Endothelial Cell ◽

Endothelial Dysfunction ◽

Corneal Endothelial Cell ◽

Endothelial Cell Dysfunction ◽

Endothelial Keratoplasty ◽

Corneal Endothelial Cells ◽

Cell Dysfunction ◽

Corneal Endothelial Dysfunction

A transparent cornea is essential for the formation of a clear image on the retina. The human cornea is arranged into well-organized layers, and each layer plays a significant role in maintaining the transparency and viability of the tissue. The endothelium has both barrier and pump functions, which are important for the maintenance of corneal clarity. Many etiologies, including Fuchs’ endothelial corneal dystrophy, surgical trauma, and congenital hereditary endothelial dystrophy, lead to endothelial cell dysfunction. The main treatment for corneal decompensation is replacement of the abnormal corneal layers with normal donor tissue. Nowadays, the trend is to perform selective endothelial keratoplasty, including Descemet stripping automated endothelial keratoplasty and Descemet’s membrane endothelial keratoplasty, to manage corneal endothelial dysfunction. This selective approach has several advantages over penetrating keratoplasty, including rapid recovery of visual acuity, less likelihood of graft rejection, and better patient satisfaction. However, the global limitation in the supply of donor corneas is becoming an increasing challenge, necessitating alternatives to reduce this demand. Consequently, in vitro expansion of human corneal endothelial cells is evolving as a sustainable choice. This method is intended to prepare corneal endothelial cells in vitro that can be transferred to the eye. Herein, we describe the etiologies and manifestations of human corneal endothelial cell dysfunction. We also summarize the available options for as well as recent developments in the management of corneal endothelial dysfunction.

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Lysine methylation is an endogenous post-translational modification of tau protein in human brain and a modulator of aggregation propensity

Biochemical Journal ◽

10.1042/bj20140372 ◽

2014 ◽

Vol 462 (1) ◽

pp. 77-88 ◽

Cited By ~ 57

Author(s):

Kristen E. Funk ◽

Stefani N. Thomas ◽

Kelsey N. Schafer ◽

Grace L. Cooper ◽

Zhongping Liao ◽

...

Keyword(s):

Human Brain ◽

Tau Protein ◽

Protein Function ◽

Lysine Methylation ◽

Post Translational Modification ◽

Post Translational Modifications ◽

Aggregation Propensity ◽

Normal Human ◽

Tau Aggregation

Diverse post-translational modifications regulate tau protein function and misfolding. In the present study we identified lysine methylation as a tau post-translational modification in normal human brain, and found it depressed tau aggregation propensity when modelled in vitro.

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Hydroxytyrosol Ameliorates Endothelial Function under Inflammatory Conditions by Preventing Mitochondrial Dysfunction

Oxidative Medicine and Cellular Longevity ◽

10.1155/2018/9086947 ◽

2018 ◽

Vol 2018 ◽

pp. 1-14 ◽

Cited By ~ 25

Author(s):

Nadia Calabriso ◽

Antonio Gnoni ◽

Eleonora Stanca ◽

Alessandro Cavallo ◽

Fabrizio Damiano ◽

...

Keyword(s):

Endothelial Cells ◽

Endothelial Dysfunction ◽

Endothelial Function ◽

Mitochondrial Function ◽

Peroxisome Proliferator ◽

Dependent Manner ◽

Concentration Dependent Manner ◽

Peroxisome Proliferator Activated Receptor ◽

Inflamed Endothelium

Mitochondria are fundamental organelles producing energy and reactive oxygen species (ROS); their impaired functions play a key role in endothelial dysfunction. Hydroxytyrosol (HT), a well-known olive oil antioxidant, exerts health benefits against vascular diseases by improving endothelial function. However, the HT role in mitochondrial oxidative stress in endothelial dysfunction is not clear yet. To investigate the HT effects on mitochondrial ROS production in the inflamed endothelium, we used an in vitro model of endothelial dysfunction represented by cultured endothelial cells, challenged with phorbol myristate acetate (PMA), an inflammatory, prooxidant, and proangiogenic agent. We found that the pretreatment of endothelial cells with HT (1–30 μmol/L) suppressed inflammatory angiogenesis, a crucial aspect of endothelial dysfunction. The HT inhibitory effect is related to reduced mitochondrial superoxide production and lipid peroxidation and to increased superoxide dismutase activity. HT, in a concentration-dependent manner, improved endothelial mitochondrial function by reverting the PMA-induced reduction of mitochondrial membrane potential, ATP synthesis, and ATP5β expression. In PMA-challenged endothelial cells, HT also promoted mitochondrial biogenesis through increased mitochondrial DNA content and expression of peroxisome proliferator-activated receptor gamma coactivator 1-alpha, nuclear respiratory factor-1, and mitochondrial transcription factor A. These results highlight that HT blunts endothelial dysfunction and pathological angiogenesis by ameliorating mitochondrial function, thus suggesting HT as a potential mitochondria-targeting antioxidant in the inflamed endothelium.

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When the chains do not break: the role of USP10 in physiology and pathology

Cell Death and Disease ◽

10.1038/s41419-020-03246-7 ◽

2020 ◽

Vol 11 (12) ◽

Author(s):

Udayan Bhattacharya ◽

Fiifi Neizer-Ashun ◽

Priyabrata Mukherjee ◽

Resham Bhattacharya

Keyword(s):

Complex Formation ◽

Molecular Mechanisms ◽

Protein Homeostasis ◽

Post Translational Modification ◽

Intracellular Protein ◽

Lysosomal Degradation ◽

Life Activity ◽

Cellular Processes ◽

Pathological Conditions

AbstractDeubiquitination is now understood to be as important as its partner ubiquitination for the maintenance of protein half-life, activity, and localization under both normal and pathological conditions. The enzymes that remove ubiquitin from target proteins are called deubiquitinases (DUBs) and they regulate a plethora of cellular processes. DUBs are essential enzymes that maintain intracellular protein homeostasis by recycling ubiquitin. Ubiquitination is a post-translational modification where ubiquitin molecules are added to proteins thus influencing activation, localization, and complex formation. Ubiquitin also acts as a tag for protein degradation, especially by proteasomal or lysosomal degradation systems. With ~100 members, DUBs are a large enzyme family; the ubiquitin-specific peptidases (USPs) being the largest group. USP10, an important member of this family, has enormous significance in diverse cellular processes and many human diseases. In this review, we discuss recent studies that define the roles of USP10 in maintaining cellular function, its involvement in human pathologies, and the molecular mechanisms underlying its association with cancer and neurodegenerative diseases. We also discuss efforts to modulate USPs as therapy in these diseases.

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