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Shi X, Seidle KA, Simms KJ, Dong F, Chilian WM, Zhang P. Endothelial progenitor cells in the host defense response. Pharmacol Ther 2023; 241:108315. [PMID: 36436689 PMCID: PMC9944665 DOI: 10.1016/j.pharmthera.2022.108315] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 11/15/2022] [Accepted: 11/21/2022] [Indexed: 11/25/2022]
Abstract
Extensive injury of endothelial cells in blood vasculature, especially in the microcirculatory system, frequently occurs in hosts suffering from sepsis and the accompanied systemic inflammation. Pathological factors, including toxic components derived from invading microbes, oxidative stress associated with tissue ischemia/reperfusion, and vessel active mediators generated during the inflammatory response, are known to play important roles in mediating endothelial injury. Collapse of microcirculation and tissue edema developed from the failure of endothelial barrier function in vital organ systems, including the lung, brain, and kidney, are detrimental, which often predict fatal outcomes. The host body possesses a substantial capacity for maintaining vascular homeostasis and repairing endothelial damage. Bone marrow and vascular wall niches house endothelial progenitor cells (EPCs). In response to septic challenges, EPCs in their niche environment are rapidly activated for proliferation and angiogenic differentiation. In the meantime, release of EPCs from their niches into the blood stream and homing of these vascular precursors to tissue sites of injury are markedly increased. The recruited EPCs actively participate in host defense against endothelial injury and repair of damage in blood vasculature via direct differentiation into endothelial cells for re-endothelialization as well as production of vessel active mediators to exert paracrine and autocrine effects on angiogenesis/vasculogenesis. In recent years, investigations on significance of EPCs in host defense and molecular signaling mechanisms underlying regulation of the EPC response have achieved substantial progress, which promotes exploration of vascular precursor cell-based approaches for effective prevention and treatment of sepsis-induced vascular injury as well as vital organ system failure.
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Affiliation(s)
- Xin Shi
- Department of Integrative Medical Sciences, Northeast Ohio Medical University College of Medicine, Rootstown, OH 44272, United States of America
| | - Kelly A Seidle
- Department of Integrative Medical Sciences, Northeast Ohio Medical University College of Medicine, Rootstown, OH 44272, United States of America
| | - Kevin J Simms
- Department of Integrative Medical Sciences, Northeast Ohio Medical University College of Medicine, Rootstown, OH 44272, United States of America
| | - Feng Dong
- Department of Integrative Medical Sciences, Northeast Ohio Medical University College of Medicine, Rootstown, OH 44272, United States of America
| | - William M Chilian
- Department of Integrative Medical Sciences, Northeast Ohio Medical University College of Medicine, Rootstown, OH 44272, United States of America
| | - Ping Zhang
- Department of Integrative Medical Sciences, Northeast Ohio Medical University College of Medicine, Rootstown, OH 44272, United States of America.
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2
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Pei J, Harakalova M, den Ruijter H, Pasterkamp G, Duncker DJ, Verhaar MC, Asselbergs FW, Cheng C. Cardiorenal disease connection during post-menopause: The protective role of estrogen in uremic toxins induced microvascular dysfunction. Int J Cardiol 2017; 238:22-30. [PMID: 28341374 DOI: 10.1016/j.ijcard.2017.03.050] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Revised: 02/14/2017] [Accepted: 03/12/2017] [Indexed: 01/03/2023]
Abstract
Female gender, post-menopause, chronic kidney disease (CKD) and (CKD linked) microvascular disease are important risk factors for developing heart failure with preserved ejection fraction (HFpEF). Enhancing our understanding of the interrelation between these risk factors could greatly benefit the identification of new drug targets for future therapy. This review discusses the evidence for the protective role of estradiol (E2) in CKD-associated microvascular disease and related HFpEF. Elevated circulating levels of uremic toxins (UTs) during CKD may act in synergy with hormonal changes during post-menopause and could lead to coronary microvascular endothelial dysfunction in HFpEF. To elucidate the molecular mechanism involved, published transcriptome datasets of indoxyl sulfate (IS), high inorganic phosphate (HP) or E2 treated human derived endothelial cells from the NCBI Gene Expression Omnibus database were analyzed. In total, 36 genes overlapped in both IS- and HP-activated gene sets, 188 genes were increased by UTs (HP and/or IS) and decreased by E2, and 572 genes were decreased by UTs and increased by E2. Based on a comprehensive in silico analysis and literature studies of collected gene sets, we conclude that CKD-accumulated UTs could negatively impact renal and cardiac endothelial homeostasis by triggering extensive inflammatory responses and initiating dysregulation of angiogenesis. E2 may protect (myo)endothelium by inhibiting UTs-induced inflammation and ameliorating UTs-related uremic bleeding and thrombotic diathesis via restored coagulation capacity and hemostasis in injured vessels.
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Affiliation(s)
- Jiayi Pei
- Department of Nephrology and Hypertension, Division of Internal Medicine and Dermatology, University Medical Center Utrecht, The Netherlands
| | - Magdalena Harakalova
- Department of Cardiology, University Medical Center Utrecht, The Netherlands; Netherlands Heart Institute, Utrecht, The Netherlands
| | - Hester den Ruijter
- Experimental Cardiology Laboratory, Department of Experimental Cardiology, University Medical Center Utrecht, The Netherlands
| | - Gerard Pasterkamp
- Experimental Cardiology Laboratory, Department of Experimental Cardiology, University Medical Center Utrecht, The Netherlands
| | - Dirk J Duncker
- Experimental Cardiology, Department of Cardiology, Thoraxcenter Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Marianne C Verhaar
- Department of Nephrology and Hypertension, Division of Internal Medicine and Dermatology, University Medical Center Utrecht, The Netherlands
| | - Folkert W Asselbergs
- Department of Cardiology, University Medical Center Utrecht, The Netherlands; Netherlands Heart Institute, Utrecht, The Netherlands; Institute of Cardiovascular Science, University College London, United Kingdom
| | - Caroline Cheng
- Department of Nephrology and Hypertension, Division of Internal Medicine and Dermatology, University Medical Center Utrecht, The Netherlands; Experimental Cardiology, Department of Cardiology, Thoraxcenter Erasmus University Medical Center, Rotterdam, The Netherlands.
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3
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ox-LDL induces endothelial dysfunction by promoting Arp2/3 complex expression. Biochem Biophys Res Commun 2016; 475:182-8. [DOI: 10.1016/j.bbrc.2016.05.068] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Accepted: 05/12/2016] [Indexed: 01/27/2023]
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Zhang J, Yang GM, Zhu Y, Peng XY, Li T, Liu LM. Role of connexin 43 in vascular hyperpermeability and relationship to Rock1-MLC20 pathway in septic rats. Am J Physiol Lung Cell Mol Physiol 2015; 309:L1323-32. [PMID: 26342084 DOI: 10.1152/ajplung.00016.2015] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Accepted: 08/31/2015] [Indexed: 12/27/2022] Open
Abstract
Connexin (Cx)43 has been shown to participate in several cardiovascular diseases. Increased vascular permeability is a common and severe complication in sepsis or septic shock. Whether or not Cx43 takes part in the regulation of vascular permeability in severe sepsis is not known, and the underlying mechanism has not been described. With cecal ligation and puncture-induced sepsis in rats and lipopolysaccharide (LPS)-treated vascular endothelial cells (VECs) from pulmonary veins, the role of Cx43 in increased vascular permeability and its relationship to the RhoA/Rock1 pathway were studied. It was shown that vascular permeability in the lungs, kidneys, and mesentery in sepsis rats and LPS-stimulated monolayer pulmonary vein VECs was significantly increased and positively correlated with the increased expression of Cx43 and Rock1 in these organs and cultured pulmonary vein VECs. The connexin inhibitor carbenoxolone (10 mg/kg iv) and the Rock1 inhibitor Y-27632 (2 mg/kg iv) alleviated the vascular leakage of lung, mesentery, and kidney in sepsis rats. Overexpressed Cx43 increased the phosphorylation of 20-kDa myosin light chain (MLC20) and the expression of Rock1 and increased the vascular permeability and decreased the transendothelial electrical resistance of pulmonary vein VECs. Cx43 RNA interference decreased the phosphorylation of MLC20 and the expression of Rock1 and decreased LPS-stimulated hyperpermeability of cultured pulmonary vein VECs. The Rock1 inhibitor Y-27632 alleviated LPS- and overexpressed Cx43-induced hyperpermeability of monolayer pulmonary vein VECs. This report shows that Cx43 participates in the regulation of vascular permeability in sepsis and that the mechanism is related to the Rock1-MLC20 phosphorylation pathway.
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Affiliation(s)
- Jie Zhang
- State Key Laboratory of Trauma, Burns, and Combined Injury, Second Department of Research Institute of Surgery, Daping Hospital, Third Military Medical University, Chongqing, People's Republic of China
| | - Guang-Ming Yang
- State Key Laboratory of Trauma, Burns, and Combined Injury, Second Department of Research Institute of Surgery, Daping Hospital, Third Military Medical University, Chongqing, People's Republic of China
| | - Yu Zhu
- State Key Laboratory of Trauma, Burns, and Combined Injury, Second Department of Research Institute of Surgery, Daping Hospital, Third Military Medical University, Chongqing, People's Republic of China
| | - Xiao-Yong Peng
- State Key Laboratory of Trauma, Burns, and Combined Injury, Second Department of Research Institute of Surgery, Daping Hospital, Third Military Medical University, Chongqing, People's Republic of China
| | - Tao Li
- State Key Laboratory of Trauma, Burns, and Combined Injury, Second Department of Research Institute of Surgery, Daping Hospital, Third Military Medical University, Chongqing, People's Republic of China
| | - Liang-Ming Liu
- State Key Laboratory of Trauma, Burns, and Combined Injury, Second Department of Research Institute of Surgery, Daping Hospital, Third Military Medical University, Chongqing, People's Republic of China
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5
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Study on the deformation of endothelial cells using a bio-inspired in vitro disease model. Microvasc Res 2015; 98:172-82. [DOI: 10.1016/j.mvr.2014.02.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Revised: 12/12/2013] [Accepted: 02/03/2014] [Indexed: 01/12/2023]
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Seo E, Seo KW, Gil JE, Ha YR, Yeom E, Lee S, Lee SJ. Biophysiochemical properties of endothelial cells cultured on bio-inspired collagen films. BMC Biotechnol 2014; 14:61. [PMID: 24984812 PMCID: PMC4085646 DOI: 10.1186/1472-6750-14-61] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Accepted: 06/26/2014] [Indexed: 11/23/2022] Open
Abstract
Background In this study, we investigated the effect of the extracellular matrix on
endothelial dysfunction by careful observation of human umbilical vein
endothelial cells (HUVECs) cultured on denatured collagen film. Results HUVECs on denatured collagen film showed relatively high surface roughness
compared with normal HUVECs. The expression levels of MMP-1, MMP-2 and CD146
increased in the ECs on denatured collagen film. In addition, we examined
the accumulation of fluorescent beads on HUVEC layers subjected to
circulatory flow. The number of accumulated fluorescent beads increased on
the disorganized HUVEC layers. Conclusions The proposed in vitro study using bio-inspired collagen films could
potentially be used in the size- and ligand-based design of drugs to treat
endothelial dysfunction caused by circulatory vascular diseases.
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Affiliation(s)
| | | | | | | | | | | | - Sang Joon Lee
- Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, San 31, Hyoja-dong, Nam-Gu, Pohang, Gyeongbuk 790-784, Korea.
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7
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Reichenberg Y, Lanir Y. Duration of microbead seeding on endothelial cells significantly affects their response to magnetic excitation. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2012; 85:041915. [PMID: 22680506 DOI: 10.1103/physreve.85.041915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2011] [Revised: 03/10/2012] [Indexed: 06/01/2023]
Abstract
Our investigation of endothelial cell rheology using optical magnetic twisting cytometry revealed that with time following incubation of ferromagnetic beads on the cells, beads were sinking into the cells and an increasing number of beads demonstrated apparent absurd negative rheological properties. In parallel, the beads' average rheological response changed considerably over time, both in magnitude and in distribution. It was hypothesized that the apparent negative rheological response was related to the above sinking process of seeded beads into the cells, resulting in an elevation of the beads' rotation axis, thus causing a reversal of the beads' lateral movement direction in response to twisting external magnetic excitation. The results suggest that microbead-based rheological characterization of cells should be interpreted with caution, while considering the time of data acquisition.
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Affiliation(s)
- Yaniv Reichenberg
- Faculty of Biomedical Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel.
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8
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Pasteurella multocida toxin interaction with host cells: entry and cellular effects. Curr Top Microbiol Immunol 2012; 361:93-111. [PMID: 22552700 PMCID: PMC4408768 DOI: 10.1007/82_2012_219] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The mitogenic dermonecrotic toxin from Pasteurella multocida (PMT) is a 1285-residue multipartite protein that belongs to the A-B family of bacterial protein toxins. Through its G-protein-deamidating activity on the α subunits of heterotrimeric G(q)-, G(i)- and G(12/13)-proteins, PMT potently stimulates downstream mitogenic, calcium, and cytoskeletal signaling pathways. These activities lead to pleiotropic effects in different cell types, which ultimately result in cellular proliferation, while inhibiting cellular differentiation, and account for the myriad of physiological outcomes observed during infection with toxinogenic strains of P. multocida.
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Abstract
The mitogenic toxin from Pasteurella multocida (PMT) is a member of the dermonecrotic toxin family, which includes toxins from Bordetella, Escherichia coli and Yersinia. Members of the dermonecrotic toxin family modulate G-protein targets in host cells through selective deamidation and/or transglutamination of a critical active site Gln residue in the G-protein target, which results in the activation of intrinsic GTPase activity. Structural and biochemical data point to the uniqueness of PMT among these toxins in its structure and action. Whereas the other dermonecrotic toxins act on small Rho GTPases, PMT acts on the α subunits of heterotrimeric G(q) -, G(i) - and G(12/13) -protein families. To date, experimental evidence supports a model in which PMT potently stimulates various mitogenic and survival pathways through the activation of G(q) and G(12/13) signaling, ultimately leading to cellular proliferation, whilst strongly inhibiting pathways involved in cellular differentiation through the activation of G(i) signaling. The resulting cellular outcomes account for the global physiological effects observed during infection with toxinogenic P. multocida, and hint at potential long-term sequelae that may result from PMT exposure.
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Affiliation(s)
- Brenda A Wilson
- Department of Microbiology and Host-Microbe Systems Theme of the Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
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10
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Evidence for involvement of ROCK signaling in bradykinin-induced increase in murine blood–tumor barrier permeability. J Neurooncol 2011; 106:291-301. [DOI: 10.1007/s11060-011-0685-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2010] [Accepted: 08/03/2011] [Indexed: 01/23/2023]
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11
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Wilson BA, Ho M. Recent insights into Pasteurella multocida toxin and other G-protein-modulating bacterial toxins. Future Microbiol 2010; 5:1185-201. [PMID: 20722598 DOI: 10.2217/fmb.10.91] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Over the past few decades, our understanding of the bacterial protein toxins that modulate G proteins has advanced tremendously through extensive biochemical and structural analyses. This article provides an updated survey of the various toxins that target G proteins, ending with a focus on recent mechanistic insights in our understanding of the deamidating toxin family. The dermonecrotic toxin from Pasteurella multocida (PMT) was recently added to the list of toxins that disrupt G-protein signal transduction through selective deamidation of their targets. The C3 deamidase domain of PMT has no sequence similarity to the deamidase domains of the dermonecrotic toxins from Escherichia coli (cytotoxic necrotizing factor [CNF]1-3), Yersinia (CNFY) and Bordetella (dermonecrotic toxin). The structure of PMT-C3 belongs to a family of transglutaminase-like proteins, with active site Cys-His-Asp catalytic triads distinct from E. coli CNF1.
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Affiliation(s)
- Brenda A Wilson
- Department of Microbiology and Institute for Genomic Biology, University of Illinois at Urbana-Champaign, 601 S. Goodwin Ave, B128 CLSL, Urbana, IL 61801, USA.
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Abstract
The pulmonary endothelium is a single-cell layer forming the inner lining of a vast network of arteries, veins, and capillaries in the lung. Its main function is to regulate the contractility of underlying vascular smooth muscle cells (SMCs), which determines vascular tone and allows adaptation of blood flow to oxygenative conditions. Low oxygen tension (hypoxia) causes vasoconstriction of pulmonary vasculature and, depending on the duration of hypoxia, this effect may be reversed by reoxygenation. The key role of the pulmonary endothelium in the regulation of vascular tone has focused considerable attention on the effects of hypoxia/reoxygenation on pulmonary endothelial barrier function. Hypoxia increases endothelial permeability, which is believed to promote vasoconstriction by facilitating the leakage of vasoactive agents from the blood to the underlying SMCs. Data show that Rho GTPases RhoA and Rac1 regulate pulmonary endothelial barrier function in response to changes in oxygen tension. This chapter describes methods to isolate and culture primary pulmonary artery endothelial cells, to measure changes in endothelial barrier function and reactive oxygen species production, and to study the role of Rho GTPases in endothelial responses to hypoxia and reoxygenation.
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Affiliation(s)
- Beata Wojciak-Stothard
- BHF Laboratories, Department of Medicine, University College London, London, United Kingdom
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13
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Hu E, Lee D. Rho kinase as potential therapeutic target for cardiovascular diseases: opportunities and challenges. Expert Opin Ther Targets 2007; 9:715-36. [PMID: 16083339 DOI: 10.1517/14728222.9.4.715] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Rho kinase (ROCK) belongs to a family of Ser/Thr protein kinases that are activated via interaction with the small GTP-binding protein RhoA. Growing evidence suggests that RhoA and ROCK participate in a variety of important physiological functions in vasculature including smooth muscle contraction, cell proliferation, cell adhesion and migration, and many aspects of inflammatory responses. As these processes mediate the onset and progression of cardiovascular disease, modulation of the Rho/ROCK signalling pathway is a potential strategy for targeting an array of cardiovascular indications. Two widely employed ROCK inhibitors, fasudil and Y-27632, have provided preliminary but compelling evidence supporting the potential cardiovascular benefits of ROCK inhibition in preclinical animal disease models and in the clinic. This review summarises the molecular biology of ROCK and its biological functions in smooth muscle, endothelium and other vascular tissues. In addition, there will be a focus on recent progress demonstrating the benefits of ROCK inhibition in several animal models of cardiovascular diseases. Finally, recent progress in the identification of novel ROCK inhibitors and challenges associated with their development for clinical use will be discussed.
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Affiliation(s)
- Erding Hu
- Center of Excellence for Cardiovascular and Urogenital Drug Discovery, Department of Vascular Biology, GlaxoSmithKline Pharmaceuticals, 709 Swedeland Road, King of Prussia, PA 19406, USA.
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14
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Abstract
Rho family GTPases are key signal transducers that regulate cell adhesion and migration and a variety of other cellular responses, including changes in gene expression. In this review, we discuss how Rho GTPases regulate signaling by endothelial cell receptors involved in leukocyte extravasation. First, Rho GTPases affect the expression of some leukocyte adhesion molecules on endothelial cells, such as intracellular adhesion molecule-1 and E-selectin, that can be induced by proinflammatory mediators, hypoxia, or shear stress. Second, Rho GTPases are activated by engagement of several leukocyte adhesion receptors and contribute to both early morphological changes and subsequent alterations in gene expression. Rho GTPases are therefore candidate targets for inhibiting leukocyte transendothelial migration in heart disease and chronic inflammatory disorders.
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Affiliation(s)
- Eva Cernuda-Morollón
- Ludwig Institute for Cancer Research, Royal Free and University College School of Medicine, London, UK
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Feneberg W, Aepfelbacher M, Sackmann E. Microviscoelasticity of the apical cell surface of human umbilical vein endothelial cells (HUVEC) within confluent monolayers. Biophys J 2005; 87:1338-50. [PMID: 15298936 PMCID: PMC1304472 DOI: 10.1529/biophysj.103.037044] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We studied the local viscoelasticity of the apical membrane of human umbilical vein endothelial cells within confluent layers by magnetic tweezers microrheometry. Magnetic beads are coupled to various integrins by coating with fibronectin or invasin. By analyzing the deflection of beads evoked by various force scenarios we demonstrate that the cell envelope behaves as a linear viscoelastic body if forces up to 2 nN are applied for short times (<20 s) but can respond in an adaptive way if stress pulses are applied longer (>30 s). The time-dependent shear relaxation modulus G(t) exhibits three time regimes: a fast response (t < 0.05 s) where the relaxation modulus G(t) obeys a power law G(t) approximately t(-0.82+/-0.02); a plateau-like behavior (at 0.05 s < t < 0.15 s); and a slow flow-like response which is, however, partially reversible. Strain field mapping experiments with colloidal probes show that local forces induce a strain field exhibiting a range of zeta = 10 +/- 1 microm, but which could only be observed if nonmagnetic beads were coupled to the cell surface by invasin. By application of the theory of elasticity of planar bodies we estimated a surface shear modulus of 2.5 x10(-4) N/m. By assuming a thickness of the actin cortex of approximately 0.5 microm we estimate a Young modulus micro approximately 400 Pa for the apical membrane. The value agrees with a plateau modulus of an entangled or weakly cross-linked actin network of an actin concentration of 100 microM (mesh size 0.2 microm). This result together with our observation of a strong reduction of the shear modulus by the actin destabilizing agent latrunculin A suggests that the shear modulus measured by our technique is determined by the actin cortex. The effect of two ligands inducing actin stress fiber formation and centripetal contraction of cells (associated with the formation of gaps in the confluent cell monolayer) on the viscoelastic responses were studied: histamine and lysophosphatidic acid (LPA). Histamine evoked a dramatic increase of the cell stiffness by >1 order of magnitude within <30 s, which is attributed to a transient rise of the intracellular Ca(2+) level, since DMSO exerted a similar effect. The stiffening is accompanied by a concomitant rounding of the cells as observed by microinterferometry and relaxes partially in the timescale of 5 min, whereas gaps between cells close after approximately 30 min. LPA did not exert a remarkable and reproducible effect other than an occasional very weak transient increase of the shear stiffness, which shows that the gap formation activated by LPA is mediated by a different mechanism than that induced by histamine.
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Affiliation(s)
- Wolfgang Feneberg
- Technische Universität München, Lehrstuhl für Biophysik E22, Garching, Germany
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Ivanov AI, Steiner AA, Scheck AC, Romanovsky AA. Expression of Eph receptors and their ligands, ephrins, during lipopolysaccharide fever in rats. Physiol Genomics 2005; 21:152-60. [PMID: 15671251 DOI: 10.1152/physiolgenomics.00043.2004] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Erythropoietin-producing hepatocellular (Eph) receptor tyrosine kinases and their ligands, ephrins, are involved in embryogenesis and oncogenesis by mediating cell adhesion and migration. Although ephrins can be induced by bacterial LPS in vitro, whether they are involved in inflammation in vivo is unknown. Using differential mRNA display, we found that a febrigenic dose of LPS (50 microg/kg iv) induces a strong transcriptional upregulation of ephrin-A1 in rat liver. We confirmed this finding by real-time RT-PCR. We then quantified the mRNA expression of different ephrins and Eph receptors at phases 1-3 of LPS fever in different organs. Febrile phases 2 (90 min post-LPS) and 3 (300 min) were characterized by robust upregulation (up to 16-fold) and downregulation (up to 21-fold) of several ephrins and Eph receptors. With the exception of EphA2, which showed upregulation in the brain at phase 2, expressional changes of Eph receptors and ephrins were limited to the LPS-processing organs: liver and lung. Characteristic, counter-directed changes in expressional regulation of Eph receptors and their corresponding ligands were found: upregulation of EphA2, downregulation of ephrin-A1 in the liver and lung at phase 2; downregulation of EphB3, upregulation of ephrin-B2 in the liver at phase 2; downregulation of EphA1 and EphA3, upregulation of ephrins-A1 and -A3 in liver at phase 3. In the liver, transcriptional changes of EphA2 and EphB3 at phase 2 were confirmed at protein level. These coordinated, phase-specific responses suggest that different sets of ephrins and Eph receptors may be involved in cellular events (such as disruption of tissue barriers and leukocyte transmigration) underlying different stages of systemic inflammatory response to LPS.
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Affiliation(s)
- Andrei I Ivanov
- Systemic Inflammation Laboratory, Trauma Research, St. Joseph's Hospital, Phoenix, Arizona 85013, USA
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Abstract
We tested the hypothesis that the equilibrium between F- and G-actin in endothelial cells modulates the integrity of the actin cytoskeleton and is important for the maintenance of endothelial barrier functions in vivo and in vitro. We used the actin-depolymerizing agent cytochalasin D and jasplakinolide, an actin filament (F-actin) stabilizing and promoting substance, to modulate the actin cytoskeleton. Low doses of jasplakinolide (0.1 microM), which we have previously shown to reduce the permeability-increasing effect of cytochalasin D, had no influence on resting permeability of single-perfused mesenteric microvessels in vivo as well as on monolayer integrity. The F-actin content of cultured endothelial cells remained unchanged. In contrast, higher doses (10 microM) of jasplakinolide increased permeability (hydraulic conductivity) to the same extent as cytochalasin D and induced formation of intercellular gaps in cultured myocardial endothelial (MyEnd) cell monolayers. This was accompanied by a 34% increase of F-actin and pronounced disorganization of the actin cytoskeleton in MyEnd cells. Furthermore, we tested whether an increase of cAMP by forskolin and rolipram would prevent the cytochalasin D-induced barrier breakdown. Conditions that increase intracellular cAMP failed to block the cytochalasin D-induced permeability increase in vivo and the reduction of vascular endothelial cadherin-mediated adhesion in vitro. Taken together, these data support the hypothesis that the state of polymerization of the actin cytoskeleton is critical for maintenance of endothelial barrier functions and that both depolymerization by cytochalasin D and hyperpolymerization of actin by jasplakinolide resulted in an increase of microvessel permeability in vivo. However, cAMP, which is known to support endothelial barrier functions, seems to work by mechanisms other than stabilizing F-actin.
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18
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Waschke J, Drenckhahn D, Adamson RH, Curry FE. Role of adhesion and contraction in Rac 1-regulated endothelial barrier function in vivo and in vitro. Am J Physiol Heart Circ Physiol 2004; 287:H704-11. [PMID: 15044196 DOI: 10.1152/ajpheart.01076.2003] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We demonstrated previously that inhibition of the small GTPase Rac-1 by Clostridium sordellii lethal toxin (LT) increased the hydraulic conductivity (L(p)) of rat venular microvessels and induced gap formation in cultured myocardial endothelial cells (MyEnd). In MyEnd cells, we also demonstrated that both LT and cytochalasin D reduced cellular adhesion of vascular endothelial (VE)-cadherin-coated beads. Here we further evaluate the contribution of actin depolymerization, myosin-based contraction, and VE-cadherin linkage to the actin cytoskeleton to LT-induced permeability. The actin-depolymerizing agent cytochalasin D increased L(p) in single rat mesenteric microvessels to the same extent as LT over 80 min. However, whereas the actin-stabilizing agent jasplakinolide blunted the L(p) increase due to cytochalasin D by 78%, it had no effect on the LT response. This conforms to the hypothesis that the predominant mechanism whereby Rac-1 stabilizes the endothelial barrier in intact microvessels is separate from actin polymerization and likely at the level of the VE-cadherin linkage to the actin cytoskeleton. In intact vessels, neither inhibition of contraction (butanedione monoxime, an inhibitor of myosin ATPase) nor inhibition of Rho kinase (Y-27632) modified the response to LT, even though both inhibitors lowered resting L(p). In contrast butanedione monoxime and inhibition of myosin light chain kinase completely inhibited LT-induced intercellular gap formation and largely reduced the LT-induced permeability increase in MyEnd monolayers. These results support the hypothesis that the contractile mechanisms that contribute to the formation of large gaps between cultured endothelial cells exposed to inflammatory conditions do not significantly contribute to increased permeability in intact microvessels.
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Affiliation(s)
- J Waschke
- Institute of Anatomy and Cell Biology, University of Würzburg, Würzburg, Germany
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Wilson BA, Ho M. Pasteurella multocida toxin as a tool for studying Gq signal transduction. Rev Physiol Biochem Pharmacol 2004; 152:93-109. [PMID: 15455260 PMCID: PMC1761692 DOI: 10.1007/s10254-004-0032-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Pasteurella multocida toxin (PMT) stimulates and subsequently uncouples phospholipase C (PLC) signal transduction through its selective action on the Galphaq subunit. This review summarizes what is currently known about the molecular action of PMT on Gq and the resulting cellular effects. Examples are presented illustrating the use of PMT as a powerful tool for dissecting the molecular mechanisms involving pertussis toxin (PT)-insensitive heterotrimeric G proteins.
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Affiliation(s)
- B A Wilson
- Department of Microbiology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
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20
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Waschke J, Baumgartner W, Adamson RH, Zeng M, Aktories K, Barth H, Wilde C, Curry FE, Drenckhahn D. Requirement of Rac activity for maintenance of capillary endothelial barrier properties. Am J Physiol Heart Circ Physiol 2004; 286:H394-401. [PMID: 14512275 DOI: 10.1152/ajpheart.00221.2003] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Our previous experiments indicated that GTPases, other than RhoA, are important for the maintenance of endothelial barrier integrity in both intact microvessels of rats and mice and cultured mouse myocardial endothelial (MyEnd) cell monolayers ( J Physiol 539: 295–308, 2002). In the present study, we inhibited the endothelial GTPase Rac by Clostridium sordellii lethal toxin (LT) and investigated the relation between the degree of inhibition of Rac by glucosylation and increased endothelial barrier permeability. In rat venular microvessels, LT (200 ng/ml) increased hydraulic conductivity from a control value of 2.5 ± 0.6 to 100.8 ± 18.7 × 10–7cm·s–1·cmH2O–1after 80 min. In cultured MyEnd cells exposed to LT (200 ng/ml), up to 60% of cellular Rac was glucosylated after 90 min, resulting in depolymerization of F-actin and interruptions of junctional distribution of vascular endothelial cadherin (VE-cadherin) and β-catenin as well as the formation of intercellular gaps. To understand the mechanism by which inhibition of Rac caused disassembly of adherens junctions, we used laser tweezers to quantify VE-cadherin-mediated adhesion. LT and cytochalasin D, an actin depolymerizing agent, both reduced adhesion of VE-cadherin-coated microbeads to the endothelial cell surface, whereas the inhibitor of Rho kinase Y-27632 did not. Stabilization of actin filaments by jasplakinolide completely blocked the effect of cytochalasin D but not of LT on bead adhesion. We conclude that Rac regulates endothelial barrier properties in vivo and in vitro by 1) modulation of actin filament polymerization and 2) acting directly on the tether between VE-cadherin and the cytoskeleton.
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Affiliation(s)
- J Waschke
- Institute of Anatomy and Cell Biology, Julius-Maximilians-Univ., Koellikerstrasse 6, D-97070 Würzburg, Germany
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21
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Essler M, Linder S, Schell B, Hüfner K, Wiedemann A, Randhahn K, Staddon JM, Aepfelbacher M. Cytotoxic necrotizing factor 1 of Escherichia coli stimulates Rho/Rho-kinase-dependent myosin light-chain phosphorylation without inactivating myosin light-chain phosphatase in endothelial cells. Infect Immun 2003; 71:5188-93. [PMID: 12933863 PMCID: PMC187342 DOI: 10.1128/iai.71.9.5188-5193.2003] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2003] [Revised: 05/13/2003] [Accepted: 05/28/2003] [Indexed: 11/20/2022] Open
Abstract
Cytotoxic necrotizing factor 1 (CNF-1) is an exotoxin of Escherichia coli that constitutively activates the GTPases Rho, Rac, and CDC42. Stimulation of Rho was shown to enhance myosin light-chain (MLC) phosphorylation via Rho kinase-mediated inhibition of MLC phosphatase in endothelial cells. Here we report that 3 h after CNF stimulation of endothelial cells, RhoA was activated and MLC phosphorylation was increased in a Rho/Rho-kinase-dependent manner, but no decrease in MLC phosphatase activity could be detected. Despite continuous RhoA activation, MLC phosphatase activity was doubled after 24 h of CNF stimulation, and this coincided with decreased MLC phosphorylation and cell spreading. Rac was also activated at 3 to 24 h but did not contribute to MLC phosphorylation, and its amount gradually decreased in the CNF-stimulated cells. CDC42Hs was not activated above control values by CNF. These results suggest that CNF can induce specific decoupling (Rho kinase from MLC phosphatase) and deactivation events in Rho GTPase signaling, potentially reflecting cellular protection mechanisms against permanently active Rho GTPases.
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Affiliation(s)
- Markus Essler
- Institut für Prophylaxe und Epidemiologie der Kreislaufkrankheiten, LMU München, 80336 Munich, Germany
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Holinstat M, Mehta D, Kozasa T, Minshall RD, Malik AB. Protein kinase Calpha-induced p115RhoGEF phosphorylation signals endothelial cytoskeletal rearrangement. J Biol Chem 2003; 278:28793-8. [PMID: 12754211 DOI: 10.1074/jbc.m303900200] [Citation(s) in RCA: 131] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Heterotrimeric G-proteins of the Galpha12/13 family activate Rho GTPase through the guanine nucleotide exchange factor p115RhoGEF. Because Rho activation is also dependent on protein kinase Calpha (PKCalpha), we addressed the possibility that PKCalpha can also induce Rho activation secondary to the phosphorylation of p115RhoGEF. Studies were made using human umbilical vein endothelial cells in which we addressed the mechanisms of PKCalpha-induced Rho activation and its consequences on actin cytoskeletal changes. We observed that PKCalpha associated with p115RhoGEF within 1 min of thrombin stimulation and p115RhoGEF phosphorylation was dependent on PKCalpha. Inhibition of PKCalpha-dependent p115RhoGEF phosphorylation prevented the thrombin-induced Rho activation, indicating that the response occurred downstream of PKCalpha phosphorylation of p115RhoGEF. The regulator of G-protein signaling domain of p115RhoGEF, a GTPase activating protein for G12/13, also prevented thrombin-induced Rho activation, indicating the parallel requirement of G12/13 in signaling Rho activation via p115RhoGEF. These data demonstrate a pathway of Rho activation involving PKCalpha-dependent phosphorylation of p115RhoGEF. Thus, Rho activation in endothelial cells and the subsequent actin cytoskeletal re-arrangement require the cooperative interaction of both G12/13 and PKCalpha pathways that converge at p115RhoGEF.
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Affiliation(s)
- Michael Holinstat
- Department of Pharmacology and Anesthesiology, University of Illinois, College of Medicine, Chicago, Illinois 60612, USA
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Abstract
Endothelial permeability depends on the integrity of intercellular junctions as well as actomyosin-based cell contractility. Rho GTPases have been implicated in signalling by many vasoactive substances including thrombin, tumour necrosis factor alpha (TNF-alpha), bradykinin, histamine, lysophosphatidic acid (LPA), vascular endothelial growth factor (VEGF), and hepatocyte growth factor (HGF). Two Rho family GTPases, Rho and Rac, have emerged as key regulators acting antagonistically to regulate endothelial barrier function: Rho increases actomyosin contractility, which facilitates breakdown of intercellular junctions, whereas Rac stabilizes endothelial junctions and counteracts the effects of Rho. In this review, we present evidence for the opposing effects of these two regulatory proteins and discuss links between them and other key signalling molecules such as cyclic AMP (cAMP), cyclic GMP (cGMP), phosphatidylinositide 3-kinases (PI3Ks), mitogen-activated protein kinases (MAPKs), and protein kinases C (PKCs). We also discuss strategies for targeting Rho GTPase signalling in therapies for diseases involving altered endothelial permeability.
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Affiliation(s)
- Beata Wojciak-Stothard
- Ludwig Institute for Cancer Research, Royal Free and University College School of Medicine Branch, 91 Riding House Street, London W1W 7BS, UK.
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Strey A, Janning A, Barth H, Gerke V. Endothelial Rho signaling is required for monocyte transendothelial migration. FEBS Lett 2002; 517:261-6. [PMID: 12062449 DOI: 10.1016/s0014-5793(02)02643-1] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Bacterial toxins affecting Rho activity in microvascular endothelial cells were employed to elucidate whether endothelial Rho participates in regulating the migration of monocytes across monolayers of cultured endothelial cells. Inactivation of Rho by the Clostridium C3 exoenzyme resulted in an increased adhesion of peripheral blood monocytes to the endothelium and a decreased rate of transendothelial monocyte migration. Cytotoxic necrotizing factor 1-mediated activation of endothelial Rho also reduced the rate of monocyte transmigration, but did not affect monocyte-endothelium adhesion. Thus, efficient leukocyte extravasation requires Rho signaling not only within the migrating leukocytes but also within the endothelial lining of the vessel wall.
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Affiliation(s)
- Anke Strey
- Institute of Medical Biochemistry, ZMBE, University of Münster, Münster, Germany
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