Premature senescence of endothelial cells: Methusaleh's dilemma

2006 ◽  
Vol 290 (5) ◽  
pp. H1729-H1739 ◽  
Author(s):  
Jun Chen ◽  
Michael S. Goligorsky
Keyword(s):  
Endothelial Cells ◽  
Cellular Response ◽  
Therapeutic Interventions ◽  
Premature Senescence ◽  
Functional Changes ◽  
Cell Dysfunction ◽  
A Cell ◽  
Suppression Mechanism ◽  
Senescence Program ◽  
Experimental Findings

Senescence has been considered a programmed cellular response, parallel to apoptosis, that is turned on when a cell reaches Hayflick's limit. Once cells enter the senescence program, they cease to proliferate and undergo a series of morphological and functional changes. Studies support a central role for Rb protein in controlling this process after it receives senescent signals from the p53 and p16 pathways. Cellular senescence is considered an essential contributor to the aging process and has been shown to be an important tumor suppression mechanism. In addition, emerging evidence suggests that senescence may also be involved in the pathogenesis of stem cell dysfunction and chronic human diseases. Under these circumstances cells undergo stress-induced premature senecence, which has several specific features. Focusing on endothelial cells, we discuss recent advances in our understanding of the stresses and their pathways that prompt the premature senescence response, evaluate their correlation with the apoptotic response, and examine their links to the development of chronic diseases and the impaired function of endothelial progenitor cells, with the emphasis on vasculopathy. Emerging novel therapeutic interventions based on recent experimental findings are also reviewed.

scholarly journals Ubiquinone Metabolism and Transcription HIF-1 Targets Pathway Are Toxicity Signature Pathways Present in Extracellular Vesicles of Paraquat-Exposed Human Brain Microvascular Endothelial Cells

2021 ◽  
Vol 22 (10) ◽  
pp. 5065
Author(s):  
Tatjana Vujić ◽  
Domitille Schvartz ◽  
Anton Iliuk ◽  
Jean-Charles Sanchez
Keyword(s):  
Endothelial Cells ◽  
Human Brain ◽  
Extracellular Vesicles ◽  
Physiological State ◽  
Microvascular Endothelial Cells ◽  
Brain Microvascular Endothelial Cells ◽  
Cell Of Origin ◽  
Functional Changes ◽  
Data Independent Acquisition ◽  
Microvascular Endothelial

Over the last decade, the knowledge in extracellular vesicles (EVs) biogenesis and modulation has increasingly grown. As their content reflects the physiological state of their donor cells, these “intercellular messengers” progressively became a potential source of biomarker reflecting the host cell state. However, little is known about EVs released from the human brain microvascular endothelial cells (HBMECs). The current study aimed to isolate and characterize EVs from HBMECs and to analyze their EVs proteome modulation after paraquat (PQ) stimulation, a widely used herbicide known for its neurotoxic effect. Size distribution, concentration and presence of well-known EV markers were assessed. Identification and quantification of PQ-exposed EV proteins was conducted by data-independent acquisition mass spectrometry (DIA-MS). Signature pathways of PQ-treated EVs were analyzed by gene ontology terms and pathway enrichment. Results highlighted that EVs exposed to PQ have modulated pathways, namely the ubiquinone metabolism and the transcription HIF-1 targets. These pathways may be potential molecular signatures of the PQ-induced toxicity carried by EVs that are reflecting their cell of origin by transporting with them irreversible functional changes.

scholarly journals Inflammation, epigenetics, and metabolism converge to cell senescence and ageing: the regulation and intervention

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Xudong Zhu ◽  
Zhiyang Chen ◽  
Weiyan Shen ◽  
Gang Huang ◽  
John M. Sedivy ◽  
...  
Keyword(s):  
Cell Fate ◽  
Cellular Response ◽  
State Of The Art ◽  
Cell Senescence ◽  
Therapeutic Interventions ◽  
Cell Fate Decision ◽  
The Past ◽  
Fate Decision ◽  
The Individual ◽  
Remarkable Progress

AbstractRemarkable progress in ageing research has been achieved over the past decades. General perceptions and experimental evidence pinpoint that the decline of physical function often initiates by cell senescence and organ ageing. Epigenetic dynamics and immunometabolic reprogramming link to the alterations of cellular response to intrinsic and extrinsic stimuli, representing current hotspots as they not only (re-)shape the individual cell identity, but also involve in cell fate decision. This review focuses on the present findings and emerging concepts in epigenetic, inflammatory, and metabolic regulations and the consequences of the ageing process. Potential therapeutic interventions targeting cell senescence and regulatory mechanisms, using state-of-the-art techniques are also discussed.

scholarly journals Mitochondrial Dysfunction in Atrial Fibrillation—Mechanisms and Pharmacological Interventions

2021 ◽  
Vol 10 (11) ◽  
pp. 2385
Author(s):  
Paweł Muszyński ◽  
Tomasz A. Bonda
Keyword(s):  
Atrial Fibrillation ◽  
Mitochondrial Dysfunction ◽  
Treatment Options ◽  
Therapeutic Interventions ◽  
Energy Deficit ◽  
Functional Changes ◽  
Electrical Instability ◽  
Ionic Fluxes ◽  
Prevention Methods ◽  
Invasive Techniques

Despite the enormous progress in the treatment of atrial fibrillation, mainly with the use of invasive techniques, many questions remain unanswered regarding the pathomechanism of the arrhythmia and its prevention methods. The development of atrial fibrillation requires functional changes in the myocardium that result from disturbed ionic fluxes and altered electrophysiology of the cardiomyocyte. Electrical instability and electrical remodeling underlying the arrhythmia may result from a cellular energy deficit and oxidative stress, which are caused by mitochondrial dysfunction. The significance of mitochondrial dysfunction in the pathogenesis of atrial fibrillation remains not fully elucidated; however, it is emphasized by the reduction of atrial fibrillation burden after therapeutic interventions improving the mitochondrial welfare. This review summarizes the mechanisms of mitochondrial dysfunction related to atrial fibrillation and current pharmacological treatment options targeting mitochondria to prevent or improve the outcome of atrial fibrillation.

Lipid mediators of autophagy in stress-induced premature senescence of endothelial cells

2008 ◽  
Vol 294 (3) ◽  
pp. H1119-H1129 ◽  
Author(s):  
Susann Patschan ◽  
Jun Chen ◽  
Alla Polotskaia ◽  
Natalja Mendelev ◽  
Jennifer Cheng ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Cell Death ◽  
Umbilical Vein ◽  
Acid Sphingomyelinase ◽  
Premature Senescence ◽  
Human Umbilical Vein ◽  
Glycation End Products ◽  
Umbilical Vein Endothelial Cells ◽  
Stress Induced Premature Senescence

Our group (Patschan S, Chen J, Gealekman O, Krupincza K, Wang M, Shu L, Shayman JA, Goligorsky MS; Am J Physiol Renal Physiol 294: F100–F109, 2008) previously observed an accumulation of gangliosides coincident with development of cell senescence and demonstrated lysosomal permeabilization in human umbilical vein endothelial cells exposed to glycated collagen I (GC). Therefore, we investigated whether the lysosome-dependent, caspase-independent or type 2-programmed cell death (autophagy) is involved in development of premature senescence of endothelial cells. The cleaved microtubule-associated protein 1 light-chain 3 (LC3), a marker of autophagosome formation, was overexpressed within 24 h of GC treatment; however, by 4–5 days, it was nearly undetectable. Early induction of autophagosomes was associated with their fusion with lysosomes, a phenomenon that later became subverted. Autophagic cell death can be triggered by the products of damaged plasma membrane, sphingolipids, and ceramide. We observed a clustering of membrane rafts shortly after exposure to GC; later, after 24 h, we observed an internalization, accompanied by an increased acid sphingomyelinase activity and accumulation of ceramide. Pharmacological inhibition of autophagy prevented development of premature senescence but did lead to the enhanced rate of apoptosis in human umbilical vein endothelial cells exposed to GC. Pharmacological induction of autophagy resulted in reciprocal changes. These observations appear to represent a mechanistic molecular cascade whereby advanced glycation end products like GC induce sphingomyelinase activity, accumulation of ceramide, clustering, and later internalization of lipid rafts.

scholarly journals Protein C system defects inflicted by the malaria parasite protein PfEMP1 can be overcome by a soluble EPCR variant

2015 ◽  
Vol 114 (11) ◽  
pp. 1038-1048 ◽  
Author(s):  
Eveline A. M. Bouwens ◽  
Ibai Tamayo ◽  
Louise Turner ◽  
Christian W. Wang ◽  
Monique Stins ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Severe Malaria ◽  
Protein C ◽  
Cellular Response ◽  
Malaria Parasite ◽  
Vascular Endothelial Cells ◽  
Protective Effects ◽  
Endothelial Protein C Receptor ◽  
Parasite Protein ◽  
Soluble Epcr

SummaryThe Endothelial Protein C receptor (EPCR) is essential for the anticoagulant and cytoprotective functions of the Protein C (PC) system. Selected variants of the malaria parasite protein, Plasmodium falciparum Erythrocyte Membrane Protein 1 (PfEMP1) associated with severe malaria, including cerebral malaria, specifically target EPCR on vascular endothelial cells. Here, we examine the cellular response to PfEMP1 engagement to elucidate its role in malaria pathogenesis. Binding of the CIDRα1.1 domain of PfEMP1 to EPCR obstructed activated PC (APC) binding to EPCR and induced a loss of cellular EPCR functions. CIDRα1.1 severely impaired endothelial PC activation and effectively blocked APC-mediated activation of protease-activated receptor-1 (PAR1) and associated barrier protective effects of APC on endothelial cells. A soluble EPCR variant (E86A-sEPCR) bound CIDRα1.1 with high affinity and did not interfere with (A)PC binding to cellular EPCR. E86A-sEPCR used as a decoy to capture PfEMP1, permitted normal PC activation on endothelial cells, normal barrier protective effects of APC, and greatly reduced cytoadhesion of infected erythrocytes to brain endothelial cells. These data imply important contributions of PfEMP1-induced protein C pathway defects in the pathogenesis of severe malaria. Furthermore, the E86A-sEPCR decoy provides a proof-of-principle strategy for the development of novel adjunct therapies for severe malaria.

Prelamin A accumulation in endothelial cells induces premature senescence and functional impairment

2014 ◽  
Vol 237 (1) ◽  
pp. 45-52 ◽  
Author(s):  
Nathalie Bonello-Palot ◽  
Stéphanie Simoncini ◽  
Stéphane Robert ◽  
Patrice Bourgeois ◽  
Florence Sabatier ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Functional Impairment ◽  
Premature Senescence ◽  
Prelamin A

Effects of homocysteine on endothelial nitric oxide production

2000 ◽  
Vol 279 (4) ◽  
pp. F671-F678 ◽  
Author(s):  
Xiaohui Zhang ◽  
Hong Li ◽  
Haoli Jin ◽  
Zachary Ebin ◽  
Sergey Brodsky ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Endothelial Cells ◽  
Redox State ◽  
Calcium Ionophore ◽  
No Production ◽  
Cellular Redox ◽  
A Cell ◽  
Oxide Synthase ◽  
Endothelial Nitric Oxide ◽  
Peroxynitrite Scavengers

Hyperhomocysteinemia (HHCy) is an independent and graded cardiovascular risk factor. HHCy is prevalent in patients with chronic renal failure, contributing to the increased mortality rate. Controversy exists as to the effects of HHCy on nitric oxide (NO) production: it has been shown that HHCy both increases and suppresses it. We addressed this problem by using amperometric electrochemical NO detection with a porphyrinic microelectrode to study responses of endothelial cells incubated with homocysteine (Hcy) to the stimulation with bradykinin, calcium ionophore, or l-arginine. Twenty-four-hour preincubation with Hcy (10, 20, and 50 μM) resulted in a gradual decline in responsiveness of endothelial cells to the above stimuli. Hcy did not affect the expression of endothelial nitric oxide synthase (eNOS), but it stimulated formation of superoxide anions, as judged by fluorescence of dichlorofluorescein, and peroxynitrite, as detected by using immunoprecipitation and immunoblotting of proteins modified by tyrosine nitration. Hcy did not directly affect the ability of recombinant eNOS to generate NO, but oxidation of sulfhydryl groups in eNOS reduced its NO-generating activity. Addition of 5-methyltetrahydrofolate restored NO responses to all agonists tested but affected neither the expression of the enzyme nor formation of nitrotyrosine-modified proteins. In addition, a scavenger of peroxynitrite or a cell-permeant superoxide dismutase mimetic reversed the Hcy-induced suppression of NO production by endothelial cells. In conclusion, electrochemical detection of NO release from cultured endothelial cells demonstrated that concentrations of Hcy >20 μM produce a significant indirect suppression of eNOS activity without any discernible effects on its expression. Folates, superoxide ions, and peroxynitrite scavengers restore the NO-generating activity to eNOS, collectively suggesting that cellular redox state plays an important role in HCy-suppressed NO-generating function of this enzyme.

scholarly journals Annexin II expressed by osteoblasts and endothelial cells regulates stem cell adhesion, homing, and engraftment following transplantation

Blood ◽  
2007 ◽  
Vol 110 (1) ◽  
pp. 82-90 ◽  
Author(s):  
Younghun Jung ◽  
Jingcheng Wang ◽  
Junhui Song ◽  
Yusuke Shiozawa ◽  
Jianhua Wang ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Endothelial Cells ◽  
Annexin Ii ◽  
Bone Marrow Niche ◽  
Peptide Fragments ◽  
Hematopoietic Stem ◽  
Marrow Cavity ◽  
Endosteal Niche ◽  
A Cell ◽  
Adhesive Interactions

Differentiation of hematopoietic stem cells (HSCs) after birth is largely restricted to the bone marrow cavity, where HSCs are associated closely with osteoblasts (OBs). How OBs localize HSCs to the endosteal niche remains unclear. To explore adhesive interactions between HSCs and OBs, a cell blot analysis was used that revealed 2 major bands that corresponded to monomers and multimers of annexin II (Anxa2). Immunohistochemistry revealed that OBs and marrow endothelial cells express Anxa2 at high levels. Function-blocking studies confirmed that Anxa2 mediates HSC adhesion mainly via the N-terminal portion of the Anxa2 peptide. Adhesion of HSCs to OBs derived from Anxa2-deficient animals (Anxa2−/−) was significantly impaired compared with OBs obtained from wild-type animals (Anxa2+/+). Moreover, fewer HSCs were found in the marrow of Anxa2−/− versus Anxa2+/+ animals. Short-term lodging, engraftment, and survival of irradiated mice with whole marrow cells were substantially inhibited by N-terminal peptide fragments of Anxa2 or anti-Anxa2 antibodies. Similar findings were noted in long-term competitive repopulation studies. Collectively, these findings reveal that Anxa2 regulates HSC homing and binding to the bone marrow microenvironment and suggest that Anxa2 is crucial for determining the bone marrow niche of HSCs.

Receptor-mediated transcytosis of transferrin through blood-brain barrier endothelial cells

1996 ◽  
Vol 270 (4) ◽  
pp. H1149-H1158 ◽  
Author(s):  
L. Descamps ◽  
M. P. Dehouck ◽  
G. Torpier ◽  
R. Cecchelli
Keyword(s):  
Endothelial Cells ◽  
Blood Brain Barrier ◽  
Bovine Brain ◽  
Brain Barrier ◽  
Double Labeling ◽  
Brain Capillary ◽  
Brain Capillary Endothelial Cells ◽  
Blood Brain ◽  
Capillary Endothelial Cells ◽  
A Cell

A cell culture model of the blood-brain barrier consisting of a coculture of bovine brain capillary endothelial cells (BBCECs) and astrocytes has been used to examine the mechanism of iron transport to the brain. Binding experiments showed that BBCECs express 35,000 high-affinity (concn at 50% receptor saturation = 11.3 +/- 2.1 nM) transferin (Tf) receptors per cell. In contrast to apo-transferrin (apoTf) we observed a specific transport of holo-transferrin (holoTf) across BBCECs. This transport was inhibited completely at low temperature. Moreover, the anti-Tf receptor antibody (OX-26) competitively inhibited holoTf uptake by BBCECs. Pulse-chase experiments demonstrated that only 10% of Tf was recycled to the luminal side of the cells, whereas the majority of Tf was transcytosed to the abluminal side; double-labeling experiments clearly demonstrated that iron crosses BBCECs bound to Tf. No intraendothelial degradation of Tf was observed, suggesting that the intraendothelial pathway through BBCECs bypasses the lysosomal compartment. These results clearly show that the iron-Tf complex is transcytosed across brain capillary endothelial cells by a receptor-mediated pathway without any degradation.

Sign in / Sign up

Export Citation Format

Share Document