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Knop JL, Burkard N, Danesh M, Kintrup S, Dandekar T, Srivastava M, Springer R, Hiermaier M, Wagner NM, Waschke J, Flemming S, Schlegel N. Endothelial barrier dysfunction in systemic inflammation is mediated by soluble VE-cadherin interfering VE-PTP signaling. iScience 2023; 26:108049. [PMID: 37822505 PMCID: PMC10563049 DOI: 10.1016/j.isci.2023.108049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Revised: 08/11/2023] [Accepted: 09/22/2023] [Indexed: 10/13/2023] Open
Abstract
Breakdown of endothelial barrier integrity determines organ dysfunction and outcome of patients with sepsis. Increased levels of soluble vascular endothelial (VE)-cadherin fragments (sVE-cadherin) have previously been linked with inflammation-induced loss of endothelial barrier function. We provide evidence for a causative role of sVE-cadherin to induce loss of endothelial barrier function. In patients with sepsis, sVE-cadherin levels were associated with organ dysfunction and the need for volume resuscitation. Similarly, LPS-induced systemic inflammation in rats with microvascular dysfunction was paralleled by augmented sVE-cadherin levels. Newly generated recombinant human sVE-cadherin (extracellular domains EC1-5) induced loss of endothelial barrier function in both human microvascular endothelial cells in vitro and in rat mesenteric microvessels in vivo and reduced microcirculatory flow. sVE-cadherinEC1-5 disturbed VE-cadherin-mediated adhesion and perturbed VE-protein tyrosine phosphatase (VE-PTP)/VE-cadherin interaction resulting in RhoGEF1-mediated RhoA activation. VE-PTP inhibitor AKB9778 and Rho-kinase inhibitor Y27632 blunted all sVE-cadherinEC1-5-induced effects, which uncovers a pathophysiological role of sVE-cadherin via dysbalanced VE-PTP/RhoA signaling.
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Affiliation(s)
- Juna-Lisa Knop
- Department of General, Visceral, Transplantation, Vascular and Paediatric Surgery (Department of Surgery I), University Hospital Wuerzburg, Oberduerrbacherstraße 6, D-97080 Wuerzburg, Germany
| | - Natalie Burkard
- Department of General, Visceral, Transplantation, Vascular and Paediatric Surgery (Department of Surgery I), University Hospital Wuerzburg, Oberduerrbacherstraße 6, D-97080 Wuerzburg, Germany
| | - Mahshid Danesh
- University of Wuerzburg, Department of Bioinformatics, Biocenter, Am Hubland, D-97074 Wuerzburg, Germany
| | - Sebastian Kintrup
- University Hospital Muenster, Department of Anesthesiology, Intensive Care and Pain Medicine, Albert-Schweitzer-Campus 1, 48149 Muenster, Germany
| | - Thomas Dandekar
- University of Wuerzburg, Department of Bioinformatics, Biocenter, Am Hubland, D-97074 Wuerzburg, Germany
| | | | - Rebecca Springer
- Department of General, Visceral, Transplantation, Vascular and Paediatric Surgery (Department of Surgery I), University Hospital Wuerzburg, Oberduerrbacherstraße 6, D-97080 Wuerzburg, Germany
| | - Matthias Hiermaier
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Nana-Maria Wagner
- University Hospital Muenster, Department of Anesthesiology, Intensive Care and Pain Medicine, Albert-Schweitzer-Campus 1, 48149 Muenster, Germany
- University Hospital Wuerzburg, Department of Anesthesiology, Intensive Care, Emergency and Pain Medicine, 97080 Würzburg, Germany
| | - Jens Waschke
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Sven Flemming
- Department of General, Visceral, Transplantation, Vascular and Paediatric Surgery (Department of Surgery I), University Hospital Wuerzburg, Oberduerrbacherstraße 6, D-97080 Wuerzburg, Germany
| | - Nicolas Schlegel
- Department of General, Visceral, Transplantation, Vascular and Paediatric Surgery (Department of Surgery I), University Hospital Wuerzburg, Oberduerrbacherstraße 6, D-97080 Wuerzburg, Germany
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2
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Vielmuth F, Radeva MY, Yeruva S, Sigmund AM, Waschke J. cAMP: A master regulator of cadherin-mediated binding in endothelium, epithelium and myocardium. Acta Physiol (Oxf) 2023; 238:e14006. [PMID: 37243909 DOI: 10.1111/apha.14006] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 05/05/2023] [Accepted: 05/22/2023] [Indexed: 05/29/2023]
Abstract
Regulation of cadherin-mediated cell adhesion is crucial not only for maintaining tissue integrity and barrier function in the endothelium and epithelium but also for electromechanical coupling within the myocardium. Therefore, loss of cadherin-mediated adhesion causes various disorders, including vascular inflammation and desmosome-related diseases such as the autoimmune blistering skin dermatosis pemphigus and arrhythmogenic cardiomyopathy. Mechanisms regulating cadherin-mediated binding contribute to the pathogenesis of diseases and may also be used as therapeutic targets. Over the last 30 years, cyclic adenosine 3',5'-monophosphate (cAMP) has emerged as one of the master regulators of cell adhesion in endothelium and, more recently, also in epithelial cells as well as in cardiomyocytes. A broad spectrum of experimental models from vascular physiology and cell biology applied by different generations of researchers provided evidence that not only cadherins of endothelial adherens junctions (AJ) but also desmosomal contacts in keratinocytes and the cardiomyocyte intercalated discs are central targets in this scenario. The molecular mechanisms involve protein kinase A- and exchange protein directly activated by cAMP-mediated regulation of Rho family GTPases and S665 phosphorylation of the AJ and desmosome adaptor protein plakoglobin. In line with this, phosphodiesterase 4 inhibitors such as apremilast have been proposed as a therapeutic strategy to stabilize cadherin-mediated adhesion in pemphigus and may also be effective to treat other disorders where cadherin-mediated binding is compromised.
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Affiliation(s)
- Franziska Vielmuth
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Mariya Y Radeva
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Sunil Yeruva
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Anna M Sigmund
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Jens Waschke
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, LMU Munich, Munich, Germany
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3
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Fuchs M, Kugelmann D, Schlegel N, Vielmuth F, Waschke J. Desmoglein 2 can undergo Ca2+-dependent interactions with both desmosomal and classical cadherins including E-cadherin and N-cadherin. Biophys J 2022; 121:1322-1335. [PMID: 35183520 PMCID: PMC9034291 DOI: 10.1016/j.bpj.2022.02.023] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 08/23/2021] [Accepted: 02/15/2022] [Indexed: 11/02/2022] Open
Abstract
Desmoglein (Dsg) 2 is a ubiquitously expressed desmosomal cadherin. Particularly, it is present in all cell types forming desmosomes, including epithelial cells and cardiac myocytes and is upregulated in the autoimmune skin disease pemphigus. Thus, we here characterized the binding properties of Dsg2 in more detail using atomic force microscopy (AFM). Dsg2 exhibits homophilic interactions and also heterophilic interactions with the desmosomal cadherin desmocollin (Dsc) 2, and further with the classical cadherins E-cadherin (E-Cad) and N-cadherin (N-Cad), which may be relevant for cross talk between desmosomes and adherens junctions in epithelia and cardiac myocytes. We found that all homo- and heterophilic interactions were Ca2+-dependent. All binding forces observed are in the same force range, i.e., 30 to 40 pN, except for the Dsg2/E-Cad unbinding force, which with 45 pN is significantly higher. To further characterize the nature of the interactions, we used tryptophan, a critical amino acid required for trans-interaction, and a tandem peptide (TP) designed to cross-link Dsg isoforms. TP was sufficient to prevent the tryptophan-induced loss of Dsg2 interaction with the desmosomal cadherins Dsg2 and Dsc2; however, not with the classical cadherins E-Cad and N-Cad, indicating that the interaction modes of Dsg2 with desmosomal and classical cadherins differ. TP rescued the tryptophan-induced loss of Dsg2 binding on living enterocytes, suggesting that interaction with desmosomal cadherins may be more relevant. In summary, the data suggest that the ubiquitous desmosomal cadherin Dsg2 enables the cross talk with adherens junctions by interacting with multiple binding partners with implications for proper adhesive function in healthy and diseased states.
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Markowska A, Markowski AR, Jarocka-Karpowicz I. The Importance of 6-Aminohexanoic Acid as a Hydrophobic, Flexible Structural Element. Int J Mol Sci 2021; 22:12122. [PMID: 34830000 PMCID: PMC8618066 DOI: 10.3390/ijms222212122] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 11/02/2021] [Accepted: 11/05/2021] [Indexed: 11/17/2022] Open
Abstract
6-aminohexanoic acid is an ω-amino acid with a hydrophobic, flexible structure. Although the ω-amino acid in question is mainly used clinically as an antifibrinolytic drug, other applications are also interesting and important. This synthetic lysine derivative, without an α-amino group, plays a significant role in chemical synthesis of modified peptides and in the polyamide synthetic fibers (nylon) industry. It is also often used as a linker in various biologically active structures. This review concentrates on the role of 6-aminohexanoic acid in the structure of various molecules.
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Affiliation(s)
- Agnieszka Markowska
- Department of Analytical Chemistry, Medical University of Bialystok, 15-089 Bialystok, Poland;
| | - Adam Roman Markowski
- Department of Internal Medicine and Gastroenterology, Polish Red Cross Memorial Municipal Hospital, 79 Henryk Sienkiewicz Street, 15-003 Bialystok, Poland;
| | - Iwona Jarocka-Karpowicz
- Department of Analytical Chemistry, Medical University of Bialystok, 15-089 Bialystok, Poland;
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New mechanism-based approaches to treating and evaluating the vasculopathy of scleroderma. Curr Opin Rheumatol 2021; 33:471-479. [PMID: 34402454 DOI: 10.1097/bor.0000000000000830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
PURPOSE OF REVIEW Utilizing recent insight into the vasculopathy of scleroderma (SSc), the review will highlight new opportunities for evaluating and treating the disease by promoting stabilization and protection of the microvasculature. RECENT FINDINGS Endothelial junctional signaling initiated by vascular endothelial-cadherin (VE-cadherin) and Tie2 receptors, which are fundamental to promoting vascular health and stability, are disrupted in SSc. This would be expected to not only diminish their protective activity, but also increase pathological processes that are normally restrained by these signaling mediators, resulting in pathological changes in vascular function and structure. Indeed, key features of SSc vasculopathy, from the earliest signs of edema and puffy fingers to pathological disruption of hemodynamics, nutritional blood flow, capillary structure and angiogenesis are all consistent with this altered endothelial signaling. It also likely contributes to further progression of the disease including tissue fibrosis, and organ and tissue injury. SUMMARY Restoring protective endothelial junctional signaling should combat the vasculopathy of SSc and prevent further deterioration in vascular and organ function. Indeed, this type of targeted approach has achieved remarkable results in preclinical models for other diseases. Furthermore, tracking this endothelial junctional signaling, for example by assessing vascular permeability, should facilitate insight into disease progression and its response to therapy.
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Rastogi M, Singh SK. Zika virus NS1 affects the junctional integrity of human brain microvascular endothelial cells. Biochimie 2020; 176:52-61. [PMID: 32640279 DOI: 10.1016/j.biochi.2020.06.011] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 06/25/2020] [Accepted: 06/29/2020] [Indexed: 12/20/2022]
Abstract
Zika virus (ZIKV) infection leads to microcephaly in newborns. Flaviviruses are known to secrete NS1 protein extracellularly and its concentration in serum directly co-relate to disease severity. The presence of ZIKV-NS1 near the brain microvascular endothelial cells (BMVECs) affects blood-brain-barrier, which is composed of tight junctions (TJs) and adherens junctions (AJs). Viruses utilize different strategies to circumvent this barrier to enter in brain. The present study demonstrated the mechanism of junctional integrity disruption in BMVECs by ZIKV-NS1 protein exposure. The Transendothelial Electrical Resistance and sodium fluorescein migration assays revealed the endothelial barrier disruption in BMVECs exposed to ZIKV-NS1 at different time (12hr and 24hr) and doses (500 ng/mL, 1000 ng/mL and 1500 ng/mL). The exposure of ZIKV-NS1 on BMVECs led to the phosphorylation of AJs and suppression of TJs through secreted ZIKV-NS1 in a bystander fashion. The activation of NADPH dependent reactive oxygen species activity and redox sensitive tyrosine kinase further increased the phosphorylation of AJs. The reduced expression of the phosphatase led to the increased phosphorylation of the AJs. The treatment with Diphenyleneiodonium chloride rescued the phosphatase and TJs expression and suppressed the expression of kinase and AJs in BMVECs exposed to ZIKV-NS1.
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Affiliation(s)
- Meghana Rastogi
- Molecular Biology Unit, Institute of Medical Sciences, Banaras Hindu University, Varanasi, 221005, U.P, India
| | - Sunit K Singh
- Molecular Biology Unit, Institute of Medical Sciences, Banaras Hindu University, Varanasi, 221005, U.P, India.
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Schinner C, Erber BM, Yeruva S, Schlipp A, Rötzer V, Kempf E, Kant S, Leube RE, Mueller TD, Waschke J. Stabilization of desmoglein-2 binding rescues arrhythmia in arrhythmogenic cardiomyopathy. JCI Insight 2020; 5:130141. [PMID: 32376797 DOI: 10.1172/jci.insight.130141] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 04/08/2020] [Indexed: 12/28/2022] Open
Abstract
Arrhythmogenic cardiomyopathy (AC) is a genetic disease causing arrhythmia and sudden cardiac death with only symptomatic therapy available at present. Mutations of desmosomal proteins, including desmoglein-2 (Dsg2) and plakoglobin (Pg), are the major cause of AC and have been shown to lead to impaired gap junction function. Recent data indicated the involvement of anti-Dsg2 autoantibodies in AC pathogenesis. We applied a peptide to stabilize Dsg2 binding similar to a translational approach to pemphigus, which is caused by anti-desmoglein autoantibodies. We provide evidence that stabilization of Dsg2 binding by a linking peptide (Dsg2-LP) is efficient to rescue arrhythmia in an AC mouse model immediately upon perfusion. Dsg2-LP, designed to cross-link Dsg2 molecules in proximity to the known binding pocket, stabilized Dsg2-mediated interactions on the surface of living cardiomyocytes as revealed by atomic force microscopy and induced Dsg2 oligomerization. Moreover, Dsg2-LP rescued disrupted cohesion induced by siRNA-mediated Pg or Dsg2 depletion or l-tryptophan, which was applied to impair overall cadherin binding. Dsg2-LP rescued connexin-43 mislocalization and conduction irregularities in response to impaired cardiomyocyte cohesion. These results demonstrate that stabilization of Dsg2 binding by Dsg2-LP can serve as a novel approach to treat arrhythmia in patients with AC.
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Affiliation(s)
- Camilla Schinner
- Faculty of Medicine, Ludwig-Maximilians-Universität (LMU) Munich, Munich, Germany.,Department of Biomedicine, University of Basel, Basel, Switzerland
| | - Bernd Markus Erber
- Faculty of Medicine, Ludwig-Maximilians-Universität (LMU) Munich, Munich, Germany
| | - Sunil Yeruva
- Faculty of Medicine, Ludwig-Maximilians-Universität (LMU) Munich, Munich, Germany
| | - Angela Schlipp
- Faculty of Medicine, Ludwig-Maximilians-Universität (LMU) Munich, Munich, Germany
| | - Vera Rötzer
- Faculty of Medicine, Ludwig-Maximilians-Universität (LMU) Munich, Munich, Germany
| | - Ellen Kempf
- Faculty of Medicine, Ludwig-Maximilians-Universität (LMU) Munich, Munich, Germany
| | - Sebastian Kant
- Institute of Molecular and Cellular Anatomy, RWTH Aachen University, Aachen, Germany
| | - Rudolf E Leube
- Institute of Molecular and Cellular Anatomy, RWTH Aachen University, Aachen, Germany
| | - Thomas D Mueller
- Department of Molecular Plant Physiology and Biophysics, Julius-von-Sachs Institute for Biosciences, Julius-Maximilians-Universität, Würzburg, Germany
| | - Jens Waschke
- Faculty of Medicine, Ludwig-Maximilians-Universität (LMU) Munich, Munich, Germany
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8
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Juettner VV, Kruse K, Dan A, Vu VH, Khan Y, Le J, Leckband D, Komarova Y, Malik AB. VE-PTP stabilizes VE-cadherin junctions and the endothelial barrier via a phosphatase-independent mechanism. J Cell Biol 2019; 218:1725-1742. [PMID: 30948425 PMCID: PMC6504901 DOI: 10.1083/jcb.201807210] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 12/20/2018] [Accepted: 03/12/2019] [Indexed: 12/16/2022] Open
Abstract
Juettner et al. describe a novel phosphatase-activity–independent mechanism by which the phosphatase VE-PTP restricts endothelial permeability. VE-PTP functions as a scaffold that binds and inhibits the RhoGEF GEF-H1, limiting RhoA-dependent tension across VE-cadherin junctions and decreasing VE-cadherin internalization to stabilize adherens junctions and reduce endothelial permeability. Vascular endothelial (VE) protein tyrosine phosphatase (PTP) is an endothelial-specific phosphatase that stabilizes VE-cadherin junctions. Although studies have focused on the role of VE-PTP in dephosphorylating VE-cadherin in the activated endothelium, little is known of VE-PTP’s role in the quiescent endothelial monolayer. Here, we used the photoconvertible fluorescent protein VE-cadherin-Dendra2 to monitor VE-cadherin dynamics at adherens junctions (AJs) in confluent endothelial monolayers. We discovered that VE-PTP stabilizes VE-cadherin junctions by reducing the rate of VE-cadherin internalization independently of its phosphatase activity. VE-PTP serves as an adaptor protein that through binding and inhibiting the RhoGEF GEF-H1 modulates RhoA activity and tension across VE-cadherin junctions. Overexpression of the VE-PTP cytosolic domain mutant interacting with GEF-H1 in VE-PTP–depleted endothelial cells reduced GEF-H1 activity and restored VE-cadherin dynamics at AJs. Thus, VE-PTP stabilizes VE-cadherin junctions and restricts endothelial permeability by inhibiting GEF-H1, thereby limiting RhoA signaling at AJs and reducing the VE-cadherin internalization rate.
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Affiliation(s)
- Vanessa V Juettner
- Department of Pharmacology and the Center for Lung and Vascular Biology, The University of Illinois College of Medicine, Chicago, IL
| | - Kevin Kruse
- Department of Pharmacology and the Center for Lung and Vascular Biology, The University of Illinois College of Medicine, Chicago, IL
| | - Arkaprava Dan
- Department of Chemical and Biomolecular Engineering, University of Illinois College of Engineering at Urbana-Champaign, Urbana, IL
| | - Vinh H Vu
- Department of Chemical and Biomolecular Engineering, University of Illinois College of Engineering at Urbana-Champaign, Urbana, IL
| | - Yousaf Khan
- Department of Pharmacology and the Center for Lung and Vascular Biology, The University of Illinois College of Medicine, Chicago, IL
| | - Jonathan Le
- Department of Pharmacology and the Center for Lung and Vascular Biology, The University of Illinois College of Medicine, Chicago, IL
| | - Deborah Leckband
- Department of Chemical and Biomolecular Engineering, University of Illinois College of Engineering at Urbana-Champaign, Urbana, IL
| | - Yulia Komarova
- Department of Pharmacology and the Center for Lung and Vascular Biology, The University of Illinois College of Medicine, Chicago, IL
| | - Asrar B Malik
- Department of Pharmacology and the Center for Lung and Vascular Biology, The University of Illinois College of Medicine, Chicago, IL
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Abstract
Under physiological conditions, the arterial endothelium exerts a powerful protective influence to maintain vascular homeostasis. However, during the development of vascular disease, these protective activities are lost, and dysfunctional endothelial cells actually promote disease pathogenesis. Numerous investigations have analyzed the characteristics of dysfunctional endothelium with a view to understanding the processes responsible for the dysfunction and to determining their role in vascular pathology. This review adopts an alternate approach: reviewing the mechanisms that contribute to the initial formation of a healthy protective endothelium and on how those mechanisms may be disrupted, precipitating the appearance of dysfunctional endothelial cells and the progression of vascular disease. This approach, which highlights the role of endothelial adherens junctions and vascular endothelial-cadherin in endothelial maturation and endothelial dysfunction, provides new insight into the remarkable biology of this important cell layer and its role in vascular protection and vascular disease.
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10
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Radeva MY, Waschke J. Mind the gap: mechanisms regulating the endothelial barrier. Acta Physiol (Oxf) 2018; 222. [PMID: 28231640 DOI: 10.1111/apha.12860] [Citation(s) in RCA: 167] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Revised: 11/21/2016] [Accepted: 02/16/2017] [Indexed: 12/11/2022]
Abstract
The endothelial barrier consists of intercellular contacts localized in the cleft between endothelial cells, which is covered by the glycocalyx in a sievelike manner. Both types of barrier-forming junctions, i.e. the adherens junction (AJ) serving mechanical anchorage and mechanotransduction and the tight junction (TJ) sealing the intercellular space to limit paracellular permeability, are tethered to the actin cytoskeleton. Under resting conditions, the endothelium thereby builds a selective layer controlling the exchange of fluid and solutes with the surrounding tissue. However, in the situation of an inflammatory response such as in anaphylaxis or sepsis intercellular contacts disintegrate in post-capillary venules leading to intercellular gap formation. The resulting oedema can cause shock and multi-organ failure. Therefore, maintenance as well as coordinated opening and closure of interendothelial junctions is tightly regulated. The two principle underlying mechanisms comprise spatiotemporal activity control of the small GTPases Rac1 and RhoA and the balance of the phosphorylation state of AJ proteins. In the resting state, junctional Rac1 and RhoA activity is enhanced by junctional components, actin-binding proteins, cAMP signalling and extracellular cues such as sphingosine-1-phosphate (S1P) and angiopoietin-1 (Ang-1). In addition, phosphorylation of AJ components is prevented by junction-associated phosphatases including vascular endothelial protein tyrosine phosphatase (VE-PTP). In contrast, inflammatory mediators inhibiting cAMP/Rac1 signalling cause strong activation of RhoA and induce AJ phosphorylation finally leading to endocytosis and cleavage of VE-cadherin. This results in dissolution of TJs the outcome of which is endothelial barrier breakdown.
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Affiliation(s)
- M. Y. Radeva
- Institute of Anatomy and Cell Biology; Ludwig-Maximilians-Universität München; Munich Germany
| | - J. Waschke
- Institute of Anatomy and Cell Biology; Ludwig-Maximilians-Universität München; Munich Germany
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11
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Komarova YA, Kruse K, Mehta D, Malik AB. Protein Interactions at Endothelial Junctions and Signaling Mechanisms Regulating Endothelial Permeability. Circ Res 2017; 120:179-206. [PMID: 28057793 DOI: 10.1161/circresaha.116.306534] [Citation(s) in RCA: 303] [Impact Index Per Article: 43.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2016] [Revised: 10/04/2016] [Accepted: 10/06/2016] [Indexed: 12/31/2022]
Abstract
The monolayer of endothelial cells lining the vessel wall forms a semipermeable barrier (in all tissue except the relatively impermeable blood-brain and inner retinal barriers) that regulates tissue-fluid homeostasis, transport of nutrients, and migration of blood cells across the barrier. Permeability of the endothelial barrier is primarily regulated by a protein complex called adherens junctions. Adherens junctions are not static structures; they are continuously remodeled in response to mechanical and chemical cues in both physiological and pathological settings. Here, we discuss recent insights into the post-translational modifications of junctional proteins and signaling pathways regulating plasticity of adherens junctions and endothelial permeability. We also discuss in the context of what is already known and newly defined signaling pathways that mediate endothelial barrier leakiness (hyperpermeability) that are important in the pathogenesis of cardiovascular and lung diseases and vascular inflammation.
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Affiliation(s)
- Yulia A Komarova
- From the Department of Pharmacology and the Center for Lung and Vascular Biology, University of Illinois College of Medicine, Chicago
| | - Kevin Kruse
- From the Department of Pharmacology and the Center for Lung and Vascular Biology, University of Illinois College of Medicine, Chicago
| | - Dolly Mehta
- From the Department of Pharmacology and the Center for Lung and Vascular Biology, University of Illinois College of Medicine, Chicago
| | - Asrar B Malik
- From the Department of Pharmacology and the Center for Lung and Vascular Biology, University of Illinois College of Medicine, Chicago.
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12
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Lu H, Mei H, Wang F, Zhao Q, Wang S, Liu L, Cheng L. Decreased phosphorylation of PDGFR-β impairs the angiogenic potential of expanded endothelial progenitor cells via the inhibition of PI3K/Akt signaling. Int J Mol Med 2017; 39:1492-1504. [PMID: 28487975 PMCID: PMC5428960 DOI: 10.3892/ijmm.2017.2976] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Accepted: 04/21/2017] [Indexed: 11/06/2022] Open
Abstract
Human umbilical cord blood-derived endothelial progenitor cells (EPCs) have been proven to contribute to post-natal angiogenesis, and have been applied in various models of ischemia. However, to date, to the best of our knowledge, there is no available data on the angiogenic properties of EPCs during the process of in vitro expansion. In this study, we expanded EPCs to obtain cells at different passages, and analyzed their cellular properties and angiogenic ability. In the process of expansion, no changes were observed in cell cobblestone-like morphology, apoptotic rate and telomere length. However, the cell proliferative ability was significantly decreased. Additionally, the expression of CD144, CD90 and KDR was significantly downregulated in the later-passage cells. Vascular formation assay in vitro revealed that EPCs at passage 4 and 6 formed more integrated and organized capillary-like networks. In a murine model of hind limb ischemia, the transplantation of EPCs at passage 4 and 6 more effectively promoted perfusion recovery in the limbs on days 7 and 14, and promoted limb salvage and histological recovery. Furthermore, the phosphorylation levels of platelet‑derived growth factor receptor-β (PDGFR-β) were found to be significantly decreased with the in vitro expansion process, accompanied by the decreased activation of the PI3K/Akt signaling pathway. When PDGFR inhibitor was used to treat the EPCs, the differences in the angiogenic potential and migratory ability among the EPCs at different passages were no longer observed; no significant differences were also observed in the levels of phosphorylated PI3K/Akt between the EPCs at different passages following treatment with the inhibitor. On the whole, our findings indicate that the levels of phosphorylated PDGFR-β are decreased in EPCs with the in vitro expansion process, which impairs their angiogenic potential by inhibiting PI3K/Akt signaling. Our findings may aid in the more effective selection of EPCs of different passages for the clinical therapy of ischemic disease.
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Affiliation(s)
- Haiyuan Lu
- Institute of Reproduction and Stem Cell Engineering, School of Basic Medical Science, Central South University, Changsha, Hunan 410078, P.R. China
| | - Hua Mei
- National Center of Human Stem Cell Research and Engineering, Changsha, Hunan 410000, P.R. China
| | - Fan Wang
- National Center of Human Stem Cell Research and Engineering, Changsha, Hunan 410000, P.R. China
| | - Qian Zhao
- Institute of Reproduction and Stem Cell Engineering, School of Basic Medical Science, Central South University, Changsha, Hunan 410078, P.R. China
| | - Siqi Wang
- National Center of Human Stem Cell Research and Engineering, Changsha, Hunan 410000, P.R. China
| | - Lvjun Liu
- Institute of Reproduction and Stem Cell Engineering, School of Basic Medical Science, Central South University, Changsha, Hunan 410078, P.R. China
| | - Lamei Cheng
- Institute of Reproduction and Stem Cell Engineering, School of Basic Medical Science, Central South University, Changsha, Hunan 410078, P.R. China
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13
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Weth A, Dippl C, Striedner Y, Tiemann-Boege I, Vereshchaga Y, Golenhofen N, Bartelt-Kirbach B, Baumgartner W. Water transport through the intestinal epithelial barrier under different osmotic conditions is dependent on LI-cadherin trans-interaction. Tissue Barriers 2017; 5:e1285390. [PMID: 28452574 PMCID: PMC5501135 DOI: 10.1080/21688370.2017.1285390] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
In the intestine water has to be reabsorbed from the chymus across the intestinal epithelium. The osmolarity within the lumen is subjected to high variations meaning that water transport often has to take place against osmotic gradients. It has been hypothesized that LI-cadherin is important in this process by keeping the intercellular cleft narrow facilitating the buildup of an osmotic gradient allowing water reabsorption. LI-cadherin is exceptional among the cadherin superfamily with respect to its localization along the lateral plasma membrane of epithelial cells being excluded from adherens junction. Furthermore it has 7 but not 5 extracellular cadherin repeats (EC1-EC7) and a small cytosolic domain. In this study we identified the peptide VAALD as an inhibitor of LI-cadherin trans-interaction by modeling the structure of LI-cadherin and comparison with the known adhesive interfaces of E-cadherin. This inhibitory peptide was used to measure LI-cadherin dependency of water transport through a monolayer of epithelial CACO2 cells under various osmotic conditions. If LI-cadherin trans-interaction was inhibited by use of the peptide, water transport from the luminal to the basolateral side was impaired and even reversed in the case of hypertonic conditions whereas no effect could be observed at isotonic conditions. These data are in line with a recently published model predicting LI-cadherin to keep the width of the lateral intercellular cleft small. In this narrow cleft a high osmolarity can be achieved due to ion pumps yielding a standing osmotic gradient allowing water absorption from the gut even if the faeces is highly hypertonic.
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Affiliation(s)
- Agnes Weth
- a Institute of Biomedical Mechatronics, Johannes Kepler University of Linz , Linz , Austria
| | - Carsten Dippl
- a Institute of Biomedical Mechatronics, Johannes Kepler University of Linz , Linz , Austria
| | - Yasmin Striedner
- b Institute of Biophysics, Johannes Kepler University of Linz , Linz , Austria
| | - Irene Tiemann-Boege
- b Institute of Biophysics, Johannes Kepler University of Linz , Linz , Austria
| | - Yana Vereshchaga
- a Institute of Biomedical Mechatronics, Johannes Kepler University of Linz , Linz , Austria
| | - Nikola Golenhofen
- c Institute of Anatomy and Cell Biology, University of Ulm , Ulm , Germany
| | | | - Werner Baumgartner
- a Institute of Biomedical Mechatronics, Johannes Kepler University of Linz , Linz , Austria
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14
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Feng G, Sullivan DP, Han F, Muller WA. Segregation of VE-cadherin from the LBRC depends on the ectodomain sequence required for homophilic adhesion. J Cell Sci 2016; 128:576-88. [PMID: 25501813 DOI: 10.1242/jcs.159053] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The lateral border recycling compartment (LBRC) is a reticulum ofperijunctional tubulovesicular membrane that is continuous with the plasmalemma of endothelial cells and is essential for efficient transendothelial migration (TEM) of leukocytes. The LBRC contains molecules involved in TEM, such as PECAM, PVR and CD99, but not VE-cadherin. Despite its importance, how membrane proteins are included in or excluded from the LBRC is not known. Immunoelectronmicroscopy and biochemical approaches demonstrate that inclusion into the LBRC is the default pathway for transmembrane molecules present at endothelial cell borders. A chimeric molecule composed of the extracellular domain of VE-cadherin and cytoplasmic tail of PECAM (VE-CAD/PECAM) did not enter the LBRC, suggesting that VE-cadherin was excluded by a mechanism involving its extracellular domain. Deletion of the homophilic interaction domain EC1 or the homophilic interaction motif RVDAE allowed VE-CAD/PECAM and even native VE-cadherin to enter the LBRC. Similarly, treatment with RVDAE peptide to block homophilic VE-cadherin interactions allowed endogenous VE-cadherin to enter the LBRC. This suggests that homophilic interactions of VE-cadherin stabilize it at cell borders and prevent entry into the LBRC.
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Timmerman I, Daniel AE, Kroon J, van Buul JD. Leukocytes Crossing the Endothelium: A Matter of Communication. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2016; 322:281-329. [PMID: 26940521 DOI: 10.1016/bs.ircmb.2015.10.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Leukocytes cross the endothelial vessel wall in a process called transendothelial migration (TEM). The purpose of leukocyte TEM is to clear the causing agents of inflammation in underlying tissues, for example, bacteria and viruses. During TEM, endothelial cells initiate signals that attract and guide leukocytes to sites of tissue damage. Leukocytes react by attaching to these sites and signal their readiness to move back to endothelial cells. Endothelial cells in turn respond by facilitating the passage of leukocytes while retaining overall integrity. In this review, we present recent findings in the field and we have endeavored to synthesize a coherent picture of the intricate interplay between endothelial cells and leukocytes during TEM.
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Affiliation(s)
- Ilse Timmerman
- Department of Molecular Cell Biology, Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, The Netherlands
| | - Anna E Daniel
- Department of Molecular Cell Biology, Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, The Netherlands
| | - Jeffrey Kroon
- Department of Molecular Cell Biology, Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, The Netherlands
| | - Jaap D van Buul
- Department of Molecular Cell Biology, Sanquin Research and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, The Netherlands.
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16
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Flemming S, Burkard N, Renschler M, Vielmuth F, Meir M, Schick MA, Wunder C, Germer CT, Spindler V, Waschke J, Schlegel N. Soluble VE-cadherin is involved in endothelial barrier breakdown in systemic inflammation and sepsis. Cardiovasc Res 2015; 107:32-44. [DOI: 10.1093/cvr/cvv144] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 08/30/2023] Open
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17
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Wawrzyniak M, Pich C, Gross B, Schütz F, Fleury S, Quemener S, Sgandurra M, Bouchaert E, Moret C, Mury L, Rommens C, Mottaz H, Dombrowicz D, Michalik L. Endothelial, but not smooth muscle, peroxisome proliferator-activated receptor β/δ regulates vascular permeability and anaphylaxis. J Allergy Clin Immunol 2015; 135:1625-35.e5. [DOI: 10.1016/j.jaci.2014.11.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Revised: 10/21/2014] [Accepted: 11/04/2014] [Indexed: 01/07/2023]
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18
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Abstract
The endothelium forms a selective semi-permeable barrier controlling bidirectional transfer between blood vessel and irrigated tissues. This crucial function relies on the dynamic architecture of endothelial cell–cell junctions, and in particular, VE -cadherin-mediated contacts. VE -cadherin indeed chiefly organizes the opening and closing of the endothelial barrier, and is central in permeability changes. In this review, the way VE -cadherin-based contacts are formed and maintained is first presented, including molecular traits of its expression, partners, and signaling. In a second part, the mechanisms by which VE -cadherin adhesion can be disrupted, leading to cell–cell junction weakening and endothelial permeability increase, are described. Overall, the molecular basis for VE -cadherin control of the endothelial barrier function is of high interest for biomedical research, as vascular leakage is observed in many pathological conditions and human diseases.
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19
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Vielmuth F, Hartlieb E, Kugelmann D, Waschke J, Spindler V. Atomic force microscopy identifies regions of distinct desmoglein 3 adhesive properties on living keratinocytes. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2014; 11:511-20. [PMID: 25510735 DOI: 10.1016/j.nano.2014.10.006] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Revised: 09/30/2014] [Accepted: 10/19/2014] [Indexed: 11/30/2022]
Abstract
Desmosomes provide strong cell-cell adhesion which is crucial for the integrity of tissues such as the epidermis. However, nothing is known about the distribution and binding properties of desmosomal adhesion molecules on keratinocytes. Here we used atomic force microscopy (AFM) to simultaneously visualize the topography of living human keratinocytes and the distribution and binding properties of the desmosomal adhesion molecule desmoglein 3 (Dsg3). Using recombinant Dsg3 as sensor, binding events were detectable diffusely and in clusters on the cell surface and at areas of cell-cell contact. This was blocked by removing Ca(2+) and by addition of Dsg3-specific antibodies indicating homophilic Dsg3 binding. Binding forces of Dsg3 molecules were lower on the cell surface compared to areas of cell-cell contact. Our data for the first time directly demonstrate the occurrence of Dsg3 molecules outside of desmosomes and show that Dsg3 adhesive properties differ depending on their localization. From the clinical editor: Using atomic force microscopy in the study of keratinocytes, this study directly demonstrates the occurrence of desmoglein 3 molecules outside of desmosomes and reveales that the adhesive properties of these molecules do differ depending on their localization.
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Affiliation(s)
- Franziska Vielmuth
- Institute of Anatomy and Cell Biology, Department I, Ludwig-Maximilians-Universität Munich, Munich, Germany.
| | - Eva Hartlieb
- Institute of Anatomy and Cell Biology, Department I, Ludwig-Maximilians-Universität Munich, Munich, Germany.
| | - Daniela Kugelmann
- Institute of Anatomy and Cell Biology, Department I, Ludwig-Maximilians-Universität Munich, Munich, Germany.
| | - Jens Waschke
- Institute of Anatomy and Cell Biology, Department I, Ludwig-Maximilians-Universität Munich, Munich, Germany.
| | - Volker Spindler
- Institute of Anatomy and Cell Biology, Department I, Ludwig-Maximilians-Universität Munich, Munich, Germany.
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20
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Abstract
The endothelium forms a selective semi-permeable barrier controlling bidirectional transfer between blood vessel and irrigated tissues. This crucial function relies on the dynamic architecture of endothelial cell-cell junctions, and in particular, VE-cadherin-mediated contacts. VE-cadherin indeed chiefly organizes the opening and closing of the endothelial barrier, and is central in permeability changes. In this review, the way VE-cadherin-based contacts are formed and maintained is first presented, including molecular traits of its expression, partners, and signaling. In a second part, the mechanisms by which VE-cadherin adhesion can be disrupted, leading to cell-cell junction weakening and endothelial permeability increase, are described. Overall, the molecular basis for VE-cadherin control of the endothelial barrier function is of high interest for biomedical research, as vascular leakage is observed in many pathological conditions and human diseases.
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Affiliation(s)
- Julie Gavard
- Cnrs; UMR8104; Paris, France; Inserm; U1016; Paris, France; Universite Paris Descartes; Sorbonne Paris Cite; Paris, France
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21
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22
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Komarova YA, Huang F, Geyer M, Daneshjou N, Garcia A, Idalino L, Kreutz B, Mehta D, Malik AB. VE-cadherin signaling induces EB3 phosphorylation to suppress microtubule growth and assemble adherens junctions. Mol Cell 2012; 48:914-25. [PMID: 23159740 DOI: 10.1016/j.molcel.2012.10.011] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2012] [Revised: 07/23/2012] [Accepted: 10/09/2012] [Indexed: 11/28/2022]
Abstract
Vascular endothelial (VE)-cadherin homophilic adhesion controls endothelial barrier permeability through assembly of adherens junctions (AJs). We observed that loss of VE-cadherin-mediated adhesion induced the activation of Src and phospholipase C (PLC)γ2, which mediated Ca(2+) release from endoplasmic reticulum (ER) stores, resulting in activation of calcineurin (CaN), a Ca(2+)-dependent phosphatase. Downregulation of CaN activity induced phosphorylation of serine 162 in end binding (EB) protein 3. This phospho-switch was required to destabilize the EB3 dimer, suppress microtubule (MT) growth, and assemble AJs. The phospho-defective S162A EB3 mutant, in contrast, induced MT growth in confluent endothelial monolayers and disassembled AJs. Thus, VE-cadherin outside-in signaling regulates cytosolic Ca(2+) homeostasis and EB3 phosphorylation, which are required for assembly of AJs. These results identify a pivotal function of VE-cadherin homophilic interaction in modulating endothelial barrier through the tuning of MT dynamics.
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Affiliation(s)
- Yulia A Komarova
- Department of Pharmacology, University of Illinois College of Medicine, Chicago, IL 60612, USA.
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23
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Kan EM, Ling EA, Lu J. Microenvironment changes in mild traumatic brain injury. Brain Res Bull 2012; 87:359-72. [PMID: 22289840 DOI: 10.1016/j.brainresbull.2012.01.007] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2011] [Revised: 01/10/2012] [Accepted: 01/12/2012] [Indexed: 02/08/2023]
Abstract
Traumatic brain injury (TBI) is a major public-health problem for which mild TBI (MTBI) makes up majority of the cases. MTBI is a poorly-understood health problem and can persist for years manifesting into neurological and non-neurological problems that can affect functional outcome. Presently, diagnosis of MTBI is based on symptoms reporting with poor understanding of ongoing pathophysiology, hence precluding prognosis and intervention. Other than rehabilitation, there is still no pharmacological treatment for the treatment of secondary injury and prevention of the development of cognitive and behavioural problems. The lack of external injuries and absence of detectable brain abnormalities lend support to MTBI developing at the cellular and biochemical level. However, the paucity of suitable and validated non-invasive methods for accurate diagnosis of MTBI poses as a substantial challenge. Hence, it is crucial that a clinically useful evaluation and management procedure be instituted for MTBI that encompasses both molecular pathophysiology and functional outcome. The acute microenvironment changes post-MTBI presents an attractive target for modulation of MTBI symptoms and the development of cognitive changes later in life.
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Affiliation(s)
- Enci Mary Kan
- Combat Care Laboratory, Defence Medical and Environmental Research Institute, DSO National Laboratories, 27 Medical Drive, Singapore 117510, Singapore
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24
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Baumer Y, Scholz B, Ivanov S, Schlosshauer B. Telomerase-based immortalization modifies the angiogenic/inflammatory responses of human coronary artery endothelial cells. Exp Biol Med (Maywood) 2011; 236:692-700. [PMID: 21558092 DOI: 10.1258/ebm.2011.010300] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Telomerase reverse transcriptase (TERT) is fundamental in determining the life span by regulating telomere length of chromosomes. To address the question whether the enhancement of the proliferative potential hampers cell differentiation, we generated TERT-over-expressing endothelial cells (ECs) and analyzed in vitro their (1) barrier function; (2) low-density lipoprotein uptake; (3) expression pattern of six selected marker proteins; (4) angiogenic potential in four assays; and (5) inflammatory responses. In contrast to investigations with focus on other cell parameters, we demonstrate that immortalization of ECs by over-expression of TERT resulted in different angiogenic and inflammatory behavior in comparison to cells with low native telomerase levels.
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Affiliation(s)
- Yvonne Baumer
- Natural and Medical Sciences Institute at the University of Tuebingen, Regenerative Medicine I, Markwiesenstrasse 55, Reutlingen, Germany
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25
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Chtcheglova LA, Wildling L, Waschke J, Drenckhahn D, Hinterdorfer P. AFM functional imaging on vascular endothelial cells. J Mol Recognit 2010; 23:589-96. [DOI: 10.1002/jmr.1052] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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26
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Abstract
PURPOSE OF REVIEW Proper control of endothelial cell contacts is the basis for maintenance of the vascular barrier function. Loss of this function leads to leak of fluid and protein from the vasculature and extensive leaks cause shock and death. The endothelial barrier also controls the entry of leukocytes into tissue and it is believed that leukocytes target endothelial cell contacts to reach sites of inflammation. RECENT FINDINGS Within the last 2 years several new molecular players and molecular interactions have been identified that either help in stabilizing the endothelial contacts or mediate their opening if triggered by the appropriate stimuli. Novel signaling mechanisms have been identified that regulate endothelial cell contacts. Whether, how and to what extent the complex of the endothelial specific adhesion molecule vascular endothelial-cadherin and its associated catenins is involved in these processes will be a major focus of this article. SUMMARY Endothelial cell contacts are regulated by a complex interplay between various receptors and signaling mediators that control the plasticity of the cytoskeleton and the function of junctional adhesion molecules. Knowing and understanding the essential players of this network will allow development of agents that could prevent breakdown of the vascular permeability barrier in shock or that could block leukocyte extravasation and thereby antagonize inflammation.
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Price GM, Wong KHK, Truslow JG, Leung AD, Acharya C, Tien J. Effect of mechanical factors on the function of engineered human blood microvessels in microfluidic collagen gels. Biomaterials 2010; 31:6182-9. [PMID: 20537705 DOI: 10.1016/j.biomaterials.2010.04.041] [Citation(s) in RCA: 134] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2010] [Accepted: 04/21/2010] [Indexed: 11/18/2022]
Abstract
This work examines how mechanical signals affect the barrier function and stability of engineered human microvessels in microfluidic type I collagen gels. Constructs that were exposed to chronic low flow displayed high permeabilities to bovine serum albumin and 10 kDa dextran, numerous focal leaks, low size selectivity, and short lifespan of less than one week. Higher flows promoted barrier function and increased longevity; at the highest flows, the barrier function rivaled that observed in vivo, and all vessels survived to day 14. By studying the physiology of microvessels of different geometries, we established that shear stress and transmural pressure were the dominant mechanical signals that regulated barrier function and vascular stability, respectively. In microvessels that were exposed to high flow, elevation of intracellular cyclic AMP further increased the selectivity of the barrier and strongly suppressed cell proliferation. Computational models that incorporated stress dependence successfully predicted vascular phenotype. Our results indicate that the mechanical microenvironment plays a major role in the functionality and stability of engineered human microvessels in microfluidic collagen gels.
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Affiliation(s)
- Gavrielle M Price
- Department of Biomedical Engineering, Boston University, 44 Cummington Street, Boston, MA 02215, USA
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28
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Spindler V, Schlegel N, Waschke J. Role of GTPases in control of microvascular permeability. Cardiovasc Res 2010; 87:243-53. [DOI: 10.1093/cvr/cvq086] [Citation(s) in RCA: 273] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
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29
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Graziani A, Poteser M, Heupel WM, Schleifer H, Krenn M, Drenckhahn D, Romanin C, Baumgartner W, Groschner K. Cell-cell contact formation governs Ca2+ signaling by TRPC4 in the vascular endothelium: evidence for a regulatory TRPC4-beta-catenin interaction. J Biol Chem 2009; 285:4213-4223. [PMID: 19996314 PMCID: PMC2823560 DOI: 10.1074/jbc.m109.060301] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
TRPC4 is well recognized as a prominent cation channel in the vascular endothelium, but its contribution to agonist-induced endothelial Ca2+ entry is still a matter of controversy. Here we report that the cellular targeting and Ca2+ signaling function of TRPC4 is determined by the state of cell-cell adhesions during endothelial phenotype transitions. TRPC4 surface expression in human microvascular endothelial cells (HMEC-1) increased with the formation of cell-cell contacts. Epidermal growth factor recruited TRPC4 into the plasma membrane of proliferating cells but initiated retrieval of TRPC4 from the plasma membrane in quiescent, barrier-forming cells. Epidermal growth factor-induced Ca2+ entry was strongly promoted by the formation of cell-cell contacts, and both siRNA and dominant negative knockdown experiments revealed that TRPC4 mediates stimulated Ca2+ entry exclusively in proliferating clusters that form immature cell-cell contacts. TRPC4 co-precipitated with the junctional proteins β-catenin and VE-cadherin. Analysis of cellular localization of fluorescent fusion proteins provided further evidence for recruitment of TRPC4 into junctional complexes. Analysis of TRPC4 function in the HEK293 expression system identified β-catenin as a signaling molecule that enables cell-cell contact-dependent promotion of TRPC4 function. Our results place TRPC4 as a Ca2+ entry channel that is regulated by cell-cell contact formation and interaction with β-catenin. TRPC4 is suggested to serve stimulated Ca2+ entry in a specific endothelial state during the transition from a proliferating to a quiescent phenotype. Thus, TRPC4 may adopt divergent, as yet unappreciated functions in endothelial Ca2+ homeostasis and emerges as a potential key player in endothelial phenotype switching and tuning of cellular growth factor signaling.
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Affiliation(s)
- Annarita Graziani
- From the Institute of Pharmaceutical Sciences-Pharmacology and Toxicology, University of Graz, Universitätsplatz 2, 8010 Graz, Austria
| | - Michael Poteser
- From the Institute of Pharmaceutical Sciences-Pharmacology and Toxicology, University of Graz, Universitätsplatz 2, 8010 Graz, Austria
| | - Wolfgang-Moritz Heupel
- the Institute of Anatomy and Cell Biology, University of Würzburg, Koellikerstrasse 6, 97070 Würzburg, Germany
| | - Hannes Schleifer
- From the Institute of Pharmaceutical Sciences-Pharmacology and Toxicology, University of Graz, Universitätsplatz 2, 8010 Graz, Austria
| | - Martin Krenn
- From the Institute of Pharmaceutical Sciences-Pharmacology and Toxicology, University of Graz, Universitätsplatz 2, 8010 Graz, Austria
| | - Detlev Drenckhahn
- the Institute of Anatomy and Cell Biology, University of Würzburg, Koellikerstrasse 6, 97070 Würzburg, Germany
| | - Christoph Romanin
- the Institute of Biophysics, University of Linz, A-4040 Linz, Austria, and
| | - Werner Baumgartner
- the Department of Cellular Neurobionics, Institute of Biology II, RWTH-Aachen University, Kopernikusstrasse 16, 52056 Aachen, Germany
| | - Klaus Groschner
- From the Institute of Pharmaceutical Sciences-Pharmacology and Toxicology, University of Graz, Universitätsplatz 2, 8010 Graz, Austria.
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