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Lopes V, Moreira G, Bramini M, Capasso A. The potential of graphene coatings as neural interfaces. NANOSCALE HORIZONS 2024; 9:384-406. [PMID: 38231692 DOI: 10.1039/d3nh00461a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2024]
Abstract
Recent advances in nanotechnology design and fabrication have shaped the landscape for the development of ideal cell interfaces based on biomaterials. A holistic evaluation of the requirements for a cell interface is a highly complex task. Biocompatibility is a crucial requirement which is affected by the interface's properties, including elemental composition, morphology, and surface chemistry. This review explores the current state-of-the-art on graphene coatings produced by chemical vapor deposition (CVD) and applied as neural interfaces, detailing the key properties required to design an interface capable of physiologically interacting with neural cells. The interfaces are classified into substrates and scaffolds to differentiate the planar and three-dimensional environments where the cells can adhere and proliferate. The role of specific features such as mechanical properties, porosity and wettability are investigated. We further report on the specific brain-interface applications where CVD graphene paved the way to revolutionary advances in biomedicine. Future studies on the long-term effects of graphene-based materials in vivo will unlock even more potentially disruptive neuro-applications.
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Affiliation(s)
- Vicente Lopes
- International Iberian Nanotechnology Laboratory, 4715-330 Braga, Portugal.
| | - Gabriel Moreira
- International Iberian Nanotechnology Laboratory, 4715-330 Braga, Portugal.
| | - Mattia Bramini
- Department of Cell Biology, Facultad de Ciencias, Universidad de Granada, 18071 Granada, Spain.
| | - Andrea Capasso
- International Iberian Nanotechnology Laboratory, 4715-330 Braga, Portugal.
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2
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Wang X, Shen Y, Shang M, Liu X, Munn LL. Endothelial mechanobiology in atherosclerosis. Cardiovasc Res 2023; 119:1656-1675. [PMID: 37163659 PMCID: PMC10325702 DOI: 10.1093/cvr/cvad076] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Revised: 02/11/2023] [Accepted: 02/21/2023] [Indexed: 05/12/2023] Open
Abstract
Cardiovascular disease (CVD) is a serious health challenge, causing more deaths worldwide than cancer. The vascular endothelium, which forms the inner lining of blood vessels, plays a central role in maintaining vascular integrity and homeostasis and is in direct contact with the blood flow. Research over the past century has shown that mechanical perturbations of the vascular wall contribute to the formation and progression of atherosclerosis. While the straight part of the artery is exposed to sustained laminar flow and physiological high shear stress, flow near branch points or in curved vessels can exhibit 'disturbed' flow. Clinical studies as well as carefully controlled in vitro analyses have confirmed that these regions of disturbed flow, which can include low shear stress, recirculation, oscillation, or lateral flow, are preferential sites of atherosclerotic lesion formation. Because of their critical role in blood flow homeostasis, vascular endothelial cells (ECs) have mechanosensory mechanisms that allow them to react rapidly to changes in mechanical forces, and to execute context-specific adaptive responses to modulate EC functions. This review summarizes the current understanding of endothelial mechanobiology, which can guide the identification of new therapeutic targets to slow or reverse the progression of atherosclerosis.
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Affiliation(s)
- Xiaoli Wang
- Institute of Biomedical Engineering, West China School of Basic Medical Sciences & Forensic Medicine, Sichuan University, Chengdu, Sichuan 610041, China
- Department of Cardiology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310020, China
| | - Yang Shen
- Institute of Biomedical Engineering, West China School of Basic Medical Sciences & Forensic Medicine, Sichuan University, Chengdu, Sichuan 610041, China
| | - Min Shang
- Department of Cardiology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310020, China
| | - Xiaoheng Liu
- Institute of Biomedical Engineering, West China School of Basic Medical Sciences & Forensic Medicine, Sichuan University, Chengdu, Sichuan 610041, China
| | - Lance L Munn
- Steele Laboratories, Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
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3
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Meng F, Cheng H, Qian J, Dai X, Huang Y, Fan Y. In vitro fluidic systems: Applying shear stress on endothelial cells. MEDICINE IN NOVEL TECHNOLOGY AND DEVICES 2022. [DOI: 10.1016/j.medntd.2022.100143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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4
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Tsaryk R, Yucel N, Leonard EV, Diaz N, Bondareva O, Odenthal-Schnittler M, Arany Z, Vaquerizas JM, Schnittler H, Siekmann AF. Shear stress switches the association of endothelial enhancers from ETV/ETS to KLF transcription factor binding sites. Sci Rep 2022; 12:4795. [PMID: 35314737 PMCID: PMC8938417 DOI: 10.1038/s41598-022-08645-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 03/10/2022] [Indexed: 02/06/2023] Open
Abstract
Endothelial cells (ECs) lining blood vessels are exposed to mechanical forces, such as shear stress. These forces control many aspects of EC biology, including vascular tone, cell migration and proliferation. Despite a good understanding of the genes responding to shear stress, our insight into the transcriptional regulation of these genes is much more limited. Here, we set out to study alterations in the chromatin landscape of human umbilical vein endothelial cells (HUVEC) exposed to laminar shear stress. To do so, we performed ChIP-Seq for H3K27 acetylation, indicative of active enhancer elements and ATAC-Seq to mark regions of open chromatin in addition to RNA-Seq on HUVEC exposed to 6 h of laminar shear stress. Our results show a correlation of gained and lost enhancers with up and downregulated genes, respectively. DNA motif analysis revealed an over-representation of KLF transcription factor (TF) binding sites in gained enhancers, while lost enhancers contained more ETV/ETS motifs. We validated a subset of flow responsive enhancers using luciferase-based reporter constructs and CRISPR-Cas9 mediated genome editing. Lastly, we characterized the shear stress response in ECs of zebrafish embryos using RNA-Seq. Our results lay the groundwork for the exploration of shear stress responsive elements in controlling EC biology.
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Affiliation(s)
- Roman Tsaryk
- Max Planck Institute for Molecular Biomedicine, Röntgenstrasse 20, 48149, Münster, Germany
- Cells-in-Motion Cluster of Excellence (EXC 1003 - CiM), University of Münster, Münster, Germany
- Department of Cell and Developmental Biology and Cardiovascular Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Nora Yucel
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, USA
| | - Elvin V Leonard
- Max Planck Institute for Molecular Biomedicine, Röntgenstrasse 20, 48149, Münster, Germany
- Cells-in-Motion Cluster of Excellence (EXC 1003 - CiM), University of Münster, Münster, Germany
- Department of Cell and Developmental Biology and Cardiovascular Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Noelia Diaz
- Max Planck Institute for Molecular Biomedicine, Röntgenstrasse 20, 48149, Münster, Germany
- Cells-in-Motion Cluster of Excellence (EXC 1003 - CiM), University of Münster, Münster, Germany
| | - Olga Bondareva
- Cells-in-Motion Cluster of Excellence (EXC 1003 - CiM), University of Münster, Münster, Germany
- Institute of Anatomy and Vascular Biology, Faculty of Medicine, Westfälische Wilhelms-Universität Münster, Vesaliusweg 2-4, 48149, Münster, Germany
- Helmholtz Institute for Metabolic, Obesity and Vascular Research (HI-MAG) of the Helmholtz Zentrum München at the University of Leipzig and University Hospital Leipzig, Philipp-Rosenthal-Str. 27, 04103, Leipzig, Germany
| | - Maria Odenthal-Schnittler
- Max Planck Institute for Molecular Biomedicine, Röntgenstrasse 20, 48149, Münster, Germany
- Cells-in-Motion Cluster of Excellence (EXC 1003 - CiM), University of Münster, Münster, Germany
- Institute of Anatomy and Vascular Biology, Faculty of Medicine, Westfälische Wilhelms-Universität Münster, Vesaliusweg 2-4, 48149, Münster, Germany
- Institute of Neuropathology, Westfälische Wilhelms-Universität Münster, Pottkamp 2, 48149, Münster, Germany
| | - Zoltan Arany
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, USA
| | - Juan M Vaquerizas
- Max Planck Institute for Molecular Biomedicine, Röntgenstrasse 20, 48149, Münster, Germany
- Cells-in-Motion Cluster of Excellence (EXC 1003 - CiM), University of Münster, Münster, Germany
| | - Hans Schnittler
- Max Planck Institute for Molecular Biomedicine, Röntgenstrasse 20, 48149, Münster, Germany
- Cells-in-Motion Cluster of Excellence (EXC 1003 - CiM), University of Münster, Münster, Germany
- Institute of Anatomy and Vascular Biology, Faculty of Medicine, Westfälische Wilhelms-Universität Münster, Vesaliusweg 2-4, 48149, Münster, Germany
- Institute of Neuropathology, Westfälische Wilhelms-Universität Münster, Pottkamp 2, 48149, Münster, Germany
| | - Arndt F Siekmann
- Max Planck Institute for Molecular Biomedicine, Röntgenstrasse 20, 48149, Münster, Germany.
- Cells-in-Motion Cluster of Excellence (EXC 1003 - CiM), University of Münster, Münster, Germany.
- Department of Cell and Developmental Biology and Cardiovascular Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA.
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5
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Taha M, Aldirawi M, März S, Seebach J, Odenthal-Schnittler M, Bondareva O, Bojovic V, Schmandra T, Wirth B, Mietkowska M, Rottner K, Schnittler H. EPLIN-α and -β Isoforms Modulate Endothelial Cell Dynamics through a Spatiotemporally Differentiated Interaction with Actin. Cell Rep 2020; 29:1010-1026.e6. [PMID: 31644899 DOI: 10.1016/j.celrep.2019.09.043] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 08/08/2019] [Accepted: 09/13/2019] [Indexed: 12/14/2022] Open
Abstract
Actin-binding proteins are essential for linear and branched actin filament dynamics that control shape change, cell migration, and cell junction remodeling in vascular endothelium (endothelial cells [ECs]). The epithelial protein lost in neoplasm (EPLIN) is an actin-binding protein, expressed as EPLIN-α and EPLIN-β by alternative promoters; however, the isoform-specific functions are not yet understood. Aortic compared to cava vein ECs and shear stress-exposed cultured ECs express increased EPLIN-β levels that stabilize stress fibers. In contrast, EPLIN-α expression is increased in growing and migrating ECs, is targeted to membrane protrusions, and terminates their growth via interaction with the Arp2/3 complex. The data indicate that EPLIN-α controls protrusion dynamics while EPLIN-β has an actin filament stabilizing role, which is consistent with FRAP analyses demonstrating a lower EPLIN-β turnover rate compared to EPLIN-α. Together, EPLIN isoforms differentially control actin dynamics in ECs, essential in shear stress responses, cell migration, and barrier function.
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Affiliation(s)
- Muna Taha
- Institute of Anatomy and Vascular Biology, Westfälische Wilhelms University of Münster, 48149 Münster, Germany; Cells-in-Motion Cluster of Excellence (EXC 1003 CiM), Westfälische Wilhelms University of Münster, 48149 Münster, Germany
| | - Mohammed Aldirawi
- Institute of Anatomy and Vascular Biology, Westfälische Wilhelms University of Münster, 48149 Münster, Germany; Cells-in-Motion Cluster of Excellence (EXC 1003 CiM), Westfälische Wilhelms University of Münster, 48149 Münster, Germany
| | - Sigrid März
- Institute of Anatomy and Vascular Biology, Westfälische Wilhelms University of Münster, 48149 Münster, Germany; Cells-in-Motion Cluster of Excellence (EXC 1003 CiM), Westfälische Wilhelms University of Münster, 48149 Münster, Germany
| | - Jochen Seebach
- Institute of Anatomy and Vascular Biology, Westfälische Wilhelms University of Münster, 48149 Münster, Germany; Cells-in-Motion Cluster of Excellence (EXC 1003 CiM), Westfälische Wilhelms University of Münster, 48149 Münster, Germany
| | - Maria Odenthal-Schnittler
- Cells-in-Motion Cluster of Excellence (EXC 1003 CiM), Westfälische Wilhelms University of Münster, 48149 Münster, Germany; Department of Ophthalmology, Westfälische Wilhelms University of Münster, Medical Center, 48149 Münster, Germany
| | - Olga Bondareva
- Institute of Anatomy and Vascular Biology, Westfälische Wilhelms University of Münster, 48149 Münster, Germany; Cells-in-Motion Cluster of Excellence (EXC 1003 CiM), Westfälische Wilhelms University of Münster, 48149 Münster, Germany
| | - Vesna Bojovic
- Institute of Anatomy and Vascular Biology, Westfälische Wilhelms University of Münster, 48149 Münster, Germany
| | - Thomas Schmandra
- Heart and Vascular Clinic Bad Neustadt, Bad Neustadt a.d. Saale, Germany
| | - Benedikt Wirth
- Cells-in-Motion Cluster of Excellence (EXC 1003 CiM), Westfälische Wilhelms University of Münster, 48149 Münster, Germany; Institute for Analysis and Numerics, Westfälische Wilhelms University of Münster, 48149 Münster Germany
| | - Magdalena Mietkowska
- Division of Molecular Cell Biology, Zoological Institute, Technische Universität Braunschweig, Spielmannstrasse 7, 38106 Braunschweig, Germany; Molecular Cell Biology Group, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124 Braunschweig, Germany
| | - Klemens Rottner
- Division of Molecular Cell Biology, Zoological Institute, Technische Universität Braunschweig, Spielmannstrasse 7, 38106 Braunschweig, Germany; Molecular Cell Biology Group, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124 Braunschweig, Germany
| | - Hans Schnittler
- Institute of Anatomy and Vascular Biology, Westfälische Wilhelms University of Münster, 48149 Münster, Germany; Cells-in-Motion Cluster of Excellence (EXC 1003 CiM), Westfälische Wilhelms University of Münster, 48149 Münster, Germany.
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6
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Lee S, Ganesan R, Krüger-Genge A, Kratz K, Franke RP, Lendlein A, Jung F. Substrate-enzyme affinity-based surface modification strategy for endothelial cell-specific binding under shear stress. Clin Hemorheol Microcirc 2019; 75:85-98. [PMID: 31884458 DOI: 10.3233/ch-190736] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Establishing an endothelial cell (EC) monolayer on top of the blood contacting surface of grafts is considered to be a promising approach for creating a hemocompatible surface. Here we utilized the high affinity interactions between the EC plasma membrane expressed enzyme called endothelin converting enzyme-1 (ECE-1) and its corresponding substrate big Endothelin-1 (bigET-1) to engineer an EC-specific binding surface. Since enzymatic cleavage of substrates require physical interaction between the enzyme and its corresponding substrate, it was hypothesized that a surface with chemically immobilized synthetic bigET-1 will preferentially attract ECs over other types of cells found in vascular system such as vascular smooth muscle cells (VSMCs). First, the expression of ECE-1 was significantly higher in ECs, and ECs processed synthetic bigET-1 to produce ET-1 in a cell number-dependent manner. Such interaction between ECs and synthetic bigET-1 was also detectible in blood. Next, vinyl-terminated self-assembled monolayers (SAMs) were established, oxidized and activated on a glass substrate as a model to immobilize synthetic bigET-1 via amide bonds. The ECs cultured on the synthetic bigET-1-immobilized surface processed larger amount of synthetic bigET-1 to produce ET-1 compared to VSMCs (102.9±5.13 vs. 9.75±0.74 pg/ml). The number of ECs bound to the synthetic bigET-1-immobilized surface during 1 h of shearing (5dyne/cm2) was approximately 3-fold higher than that of VSMCs (46.25±12.61 vs. 15.25±3.69 cells/100×HPF). EC-specific binding of synthetic bigET-1-immobilized surface over a surface modified with collagen, a common substance for cell adhesion, was also observed. The present study demonstrated that using the substrate-enzyme affinity (SEA) of cell type-specific enzyme and its corresponding substrate can be an effective method to engineer a surface preferentially binds specific type of cells. This novel strategy might open a new route toward rapid endothelialization under dynamic conditions supporting the long-term patency of cardiovascular implants.
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Affiliation(s)
- Seahyoung Lee
- Institute of Biomaterial Science and Berlin-Brandenburg Center for Regenerative Therapies, Helmholtz-Zentrum Geesthacht, Teltow, Germany
| | - Ramakrishnan Ganesan
- Institute of Biomaterial Science and Berlin-Brandenburg Center for Regenerative Therapies, Helmholtz-Zentrum Geesthacht, Teltow, Germany
| | - Anne Krüger-Genge
- Institute of Biomaterial Science and Berlin-Brandenburg Center for Regenerative Therapies, Helmholtz-Zentrum Geesthacht, Teltow, Germany
| | - Karl Kratz
- Institute of Biomaterial Science and Berlin-Brandenburg Center for Regenerative Therapies, Helmholtz-Zentrum Geesthacht, Teltow, Germany
| | - Ralf-Peter Franke
- Central Institute for Biomedical Engineering, University of Ulm, Ulm, Germany
| | - Andreas Lendlein
- Institute of Biomaterial Science and Berlin-Brandenburg Center for Regenerative Therapies, Helmholtz-Zentrum Geesthacht, Teltow, Germany.,Institute of Chemistry, University of Potsdam, Potsdam, Germany
| | - Friedrich Jung
- Institute of Biomaterial Science and Berlin-Brandenburg Center for Regenerative Therapies, Helmholtz-Zentrum Geesthacht, Teltow, Germany
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7
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A three-step approach identifies novel shear stress-sensitive endothelial microRNAs involved in vasculoprotective effects of high-intensity interval training (HIIT). Oncotarget 2019. [DOI: 10.18632/oncotarget.26944] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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8
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Ghimire K, Zaric J, Alday-Parejo B, Seebach J, Bousquenaud M, Stalin J, Bieler G, Schnittler HJ, Rüegg C. MAGI1 Mediates eNOS Activation and NO Production in Endothelial Cells in Response to Fluid Shear Stress. Cells 2019; 8:cells8050388. [PMID: 31035633 PMCID: PMC6562810 DOI: 10.3390/cells8050388] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 04/24/2019] [Accepted: 04/26/2019] [Indexed: 12/24/2022] Open
Abstract
Fluid shear stress stimulates endothelial nitric oxide synthase (eNOS) activation and nitric oxide (NO) production through multiple kinases, including protein kinase A (PKA), AMP-activated protein kinase (AMPK), AKT and Ca2+/calmodulin-dependent protein kinase II (CaMKII). Membrane-associated guanylate kinase (MAGUK) with inverted domain structure-1 (MAGI1) is an adaptor protein that stabilizes epithelial and endothelial cell-cell contacts. The aim of this study was to assess the unknown role of endothelial cell MAGI1 in response to fluid shear stress. We show constitutive expression and co-localization of MAGI1 with vascular endothelial cadherin (VE-cadherin) in endothelial cells at cellular junctions under static and laminar flow conditions. Fluid shear stress increases MAGI1 expression. MAGI1 silencing perturbed flow-dependent responses, specifically, Krüppel-like factor 4 (KLF4) expression, endothelial cell alignment, eNOS phosphorylation and NO production. MAGI1 overexpression had opposite effects and induced phosphorylation of PKA, AMPK, and CAMKII. Pharmacological inhibition of PKA and AMPK prevented MAGI1-mediated eNOS phosphorylation. Consistently, MAGI1 silencing and PKA inhibition suppressed the flow-induced NO production. Endothelial cell-specific transgenic expression of MAGI1 induced PKA and eNOS phosphorylation in vivo and increased NO production ex vivo in isolated endothelial cells. In conclusion, we have identified endothelial cell MAGI1 as a previously unrecognized mediator of fluid shear stress-induced and PKA/AMPK dependent eNOS activation and NO production.
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Affiliation(s)
- Kedar Ghimire
- Pathology, Department of Oncology, Microbiology and Immunology, Section of Medicine, Faculty of Science and Medicine, University of Fribourg, Chemin du Musée 18, CH-1700 Fribourg, Switzerland.
| | - Jelena Zaric
- Pathology, Department of Oncology, Microbiology and Immunology, Section of Medicine, Faculty of Science and Medicine, University of Fribourg, Chemin du Musée 18, CH-1700 Fribourg, Switzerland.
| | - Begoña Alday-Parejo
- Pathology, Department of Oncology, Microbiology and Immunology, Section of Medicine, Faculty of Science and Medicine, University of Fribourg, Chemin du Musée 18, CH-1700 Fribourg, Switzerland.
| | - Jochen Seebach
- Institute of Anatomy and Vascular Biology, Westfälische, Wilhelms-Universität Münster, Vesaliusweg 2-4, D-48149 Münster, Germany.
- Cells-in-Motion Cluster of Excellence (EXC 1003-CiM), University of Muenster, D-48149 Muenster, Germany.
| | - Mélanie Bousquenaud
- Pathology, Department of Oncology, Microbiology and Immunology, Section of Medicine, Faculty of Science and Medicine, University of Fribourg, Chemin du Musée 18, CH-1700 Fribourg, Switzerland.
| | - Jimmy Stalin
- Pathology, Department of Oncology, Microbiology and Immunology, Section of Medicine, Faculty of Science and Medicine, University of Fribourg, Chemin du Musée 18, CH-1700 Fribourg, Switzerland.
| | - Grégory Bieler
- Pathology, Department of Oncology, Microbiology and Immunology, Section of Medicine, Faculty of Science and Medicine, University of Fribourg, Chemin du Musée 18, CH-1700 Fribourg, Switzerland.
| | - Hans-Joachim Schnittler
- Institute of Anatomy and Vascular Biology, Westfälische, Wilhelms-Universität Münster, Vesaliusweg 2-4, D-48149 Münster, Germany.
- Cells-in-Motion Cluster of Excellence (EXC 1003-CiM), University of Muenster, D-48149 Muenster, Germany.
| | - Curzio Rüegg
- Pathology, Department of Oncology, Microbiology and Immunology, Section of Medicine, Faculty of Science and Medicine, University of Fribourg, Chemin du Musée 18, CH-1700 Fribourg, Switzerland.
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9
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Anderson DEJ, Truong KP, Hagen MW, Yim EKF, Hinds MT. Biomimetic modification of poly(vinyl alcohol): Encouraging endothelialization and preventing thrombosis with antiplatelet monotherapy. Acta Biomater 2019; 86:291-299. [PMID: 30639349 DOI: 10.1016/j.actbio.2019.01.008] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 12/17/2018] [Accepted: 01/09/2019] [Indexed: 01/04/2023]
Abstract
Poly(vinyl alcohol) (PVA) has shown promise as a biomaterial for cardiovascular application. However, its antifouling properties prevent in vivo endothelialization. This work examined the endothelialization and thrombogenicity of modified PVA with different concentrations of proteins and adhesion peptides: collagen, laminin, fibronectin, GFPGER, YIGSR, and cRGD. Material surface properties were quantified, and the endothelialization potential was determined with human endothelial colony forming cells. Additionally, platelet attachment was assessed in vitro with human platelet rich plasma, and promising samples were tested in an ex vivo shunt model. This well-established arteriovenous shunt model was used with and without clinically-relevant antiplatelet therapies, specifically acetylsalicylic acid (ASA) with and without clopidogrel to examine the minimum necessary treatment to prevent thrombosis. Collagen, laminin, and GFPGER biomolecules increased endothelialization, with GFPGER showing the greatest effect at the lowest concentrations. GFPGER-PVA tubes tested under whole blood did exhibit an increase in platelet (but not fibrin) attachment compared to plain PVA and clinical controls. However, application of ASA monotherapy reduced the thrombogenicity of GFPGER-PVA below the clinical control with the ASA. This work is significant in developing cardiovascular biomaterials-increasing endothelialization potential while reducing bleeding side effects by using an antiplatelet monotherapy, typical of clinical patients. STATEMENT OF SIGNIFICANCE: We modified the endothelialization potential of synthetic, hydrogel vascular grafts with proteins and peptides of the vascular tissue matrix. Cell attachment was dramatically increased with the GFPGER peptide, and while some additional platelet attachment was seen under flow with whole blood, this was completely knocked down using clinical antiplatelet monotherapy. This indicates that long-term patency of this biomaterial could be improved without the associated bleeding risk of multiple platelet therapies.
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Affiliation(s)
- Deirdre E J Anderson
- Department of Biomedical Engineering, Oregon Health & Science University, 3303 SW Bond Ave., Portland, OR 97239, USA
| | - Katie P Truong
- Department of Biomedical Engineering, Oregon Health & Science University, 3303 SW Bond Ave., Portland, OR 97239, USA
| | - Matthew W Hagen
- Department of Biomedical Engineering, Oregon Health & Science University, 3303 SW Bond Ave., Portland, OR 97239, USA
| | - Evelyn K F Yim
- Department of Chemical Engineering, University of Waterloo, 200 University Ave. W, Waterloo, ON N2L3G1, Canada
| | - Monica T Hinds
- Department of Biomedical Engineering, Oregon Health & Science University, 3303 SW Bond Ave., Portland, OR 97239, USA.
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10
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Krüger-Genge A, Dietze S, Yan W, Liu Y, Fang L, Kratz K, Lendlein A, Jung F. Endothelial cell migration, adhesion and proliferation on different polymeric substrates. Clin Hemorheol Microcirc 2019; 70:511-529. [DOI: 10.3233/ch-189317] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- Anne Krüger-Genge
- Institute of Biomaterial Science and Berlin-Brandenburg Center for Regenerative Therapies, Helmholtz-Zentrum Geesthacht, Teltow, Germany
| | - Stefanie Dietze
- Institute of Biomaterial Science and Berlin-Brandenburg Center for Regenerative Therapies, Helmholtz-Zentrum Geesthacht, Teltow, Germany
| | - Wan Yan
- Institute of Biomaterial Science and Berlin-Brandenburg Center for Regenerative Therapies, Helmholtz-Zentrum Geesthacht, Teltow, Germany
- Institute of Chemistry, University of Potsdam, Potsdam, Germany
| | - Yue Liu
- Institute of Biomaterial Science and Berlin-Brandenburg Center for Regenerative Therapies, Helmholtz-Zentrum Geesthacht, Teltow, Germany
- Institute of Chemistry, University of Potsdam, Potsdam, Germany
| | - Liang Fang
- Institute of Biomaterial Science and Berlin-Brandenburg Center for Regenerative Therapies, Helmholtz-Zentrum Geesthacht, Teltow, Germany
| | - Karl Kratz
- Institute of Biomaterial Science and Berlin-Brandenburg Center for Regenerative Therapies, Helmholtz-Zentrum Geesthacht, Teltow, Germany
| | - Andreas Lendlein
- Institute of Biomaterial Science and Berlin-Brandenburg Center for Regenerative Therapies, Helmholtz-Zentrum Geesthacht, Teltow, Germany
- Institute of Chemistry, University of Potsdam, Potsdam, Germany
| | - Friedrich Jung
- Institute of Biomaterial Science and Berlin-Brandenburg Center for Regenerative Therapies, Helmholtz-Zentrum Geesthacht, Teltow, Germany
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11
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Rezaei M, Martins Cavaco AC, Seebach J, Niland S, Zimmermann J, Hanschmann EM, Hallmann R, Schillers H, Eble JA. Signals of the Neuropilin-1–MET Axis and Cues of Mechanical Force Exertion Converge to Elicit Inflammatory Activation in Coherent Endothelial Cells. THE JOURNAL OF IMMUNOLOGY 2019; 202:1559-1572. [DOI: 10.4049/jimmunol.1801346] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Accepted: 12/27/2018] [Indexed: 12/31/2022]
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12
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Baark F, Shaughnessy F, Pell VR, Clark JE, Eykyn TR, Blower P, Southworth R. Tissue acidosis does not mediate the hypoxia selectivity of [ 64Cu][Cu(ATSM)] in the isolated perfused rat heart. Sci Rep 2019; 9:499. [PMID: 30679497 PMCID: PMC6346098 DOI: 10.1038/s41598-018-36145-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Accepted: 11/15/2018] [Indexed: 01/16/2023] Open
Abstract
Copper-64-Diacetyl-bis(N4-methylthiosemicarbazone) [64Cu][Cu(ATSM)] is a hypoxia-targeting PET tracer with applications in oncology and cardiology. Upon entering a hypoxic cell, [64Cu][Cu(II)(ATSM)] is reduced to a putative [64Cu][Cu(I)(ATSM)]- species which dissociates to deposit radiocopper, thereby providing hypoxic contrast. This process may be dependent upon protonation arising from intracellular acidosis. Since acidosis is a hallmark of ischemic tissue and tumors, the hypoxia specificity of [64Cu][Cu(ATSM)] may be confounded by changes in intracellular pH. We have therefore determined the influence of intracellular pH on [64Cu][Cu(ATSM)] pharmacokinetics. Using isolated perfused rat hearts, acidosis was induced using an ammonium pre-pulse method, with and without hypoxic buffer perfusion. Cardiac [64Cu][Cu(ATSM)] pharmacokinetics were determined using NaI detectors, with intracellular pH and cardiac energetics monitored in parallel by 31P NMR. To distinguish direct acidotic effects on tracer pharmacokinetics from acidosis-induced hypocontractility, parallel studies used lidocaine perfusion to abolish cardiac contraction. Hypoxic myocardium trapped [64Cu][Cu(ATSM)] despite no evidence of it being acidotic when characterised by 31P NMR. Independent induction of tissue acidosis had no direct effect on [64Cu][Cu(ATSM)] pharmacokinetics in either normoxic or hypoxic hearts, beyond decreasing cardiac oxygen consumption to alleviate hypoxia and decrease tracer retention, leading us to conclude that tissue acidosis does not mediate the hypoxia selectivity of [64Cu][Cu(ATSM)].
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Affiliation(s)
- Friedrich Baark
- School of Biomedical Engineering & Imaging Sciences, King's College London, London, UK
- School of Cardiovascular Medicine and Sciences, BHF Centre, King's College London, London, UK
| | - Fiona Shaughnessy
- School of Biomedical Engineering & Imaging Sciences, King's College London, London, UK
| | - Victoria R Pell
- School of Biomedical Engineering & Imaging Sciences, King's College London, London, UK
- School of Cardiovascular Medicine and Sciences, BHF Centre, King's College London, London, UK
| | - James E Clark
- School of Cardiovascular Medicine and Sciences, BHF Centre, King's College London, London, UK
| | - Thomas R Eykyn
- School of Biomedical Engineering & Imaging Sciences, King's College London, London, UK
| | - Philip Blower
- School of Biomedical Engineering & Imaging Sciences, King's College London, London, UK
| | - Richard Southworth
- School of Biomedical Engineering & Imaging Sciences, King's College London, London, UK.
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13
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Avari H, Rogers KA, Savory E. Quantification of Morphological Modulation, F-Actin Remodeling and PECAM-1 (CD-31) Re-distribution in Endothelial Cells in Response to Fluid-Induced Shear Stress under Various Flow Conditions. J Biomech Eng 2019; 141:2723101. [PMID: 30673068 DOI: 10.1115/1.4042601] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Indexed: 12/19/2022]
Abstract
Cardiovascular diseases (CVDs) are the number one cause of death globally. Arterial endothelial cell (EC) dysfunction plays a key role in many of these CVDs, such as atherosclerosis. Blood flow-induced wall shear stress (WSS), among many other pathophysiological factors, is known to significantly contribute to EC dysfunction. The present study reports an in vitro investigation of the effect of quantified WSS on ECs, analyzing the EC morphometric parameters as well as cytoskeletal remodeling. The effects of four different flow cases (low steady laminar (LSL), medium steady laminar (MSL), non-zero-mean sinusoidal laminar (NZMSL) and laminar carotid (LCRD) waveforms) on EC area, perimeter, shape index (SI), angle of orientation, F-actin bundle remodeling and PECAM-1 localization were studied. For the first time, a flow facility was fully quantified for the uniformity of flow over ECs as well as for WSS determination (as opposed to relying on analytical equations). The SI and angle of orientation were found to be the most flow-sensitive morphometric parameters. A 2D Fast Fourier Transform based image processing technique was applied to analyze the F-actin directionality and an alignment index (AI) was defined accordingly. Also, a significant peripheral loss of PECAM-1 in ECs subjected to atheroprone cases (LSL and NZMSL) with high cell surface/cytoplasm stain of this protein is reported, which may shed light on of the mechanosensory role of PECAM-1 in mechanotransduction.
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Affiliation(s)
- Hamed Avari
- Advanced Fluid Mechanics Research Group, Department of Mechanical and Materials Engineering, University of Western Ontario, London, Ontario, Canada, N6A 3K7
| | - Kem A Rogers
- Department of Anatomy and Cell Biology, University of Western Ontario, London, Ontario, Canada, N6A 3K7
| | - Eric Savory
- Advanced Fluid Mechanics Research Group, Department of Mechanical and Materials Engineering, University of Western Ontario, London, Ontario, Canada, N6A 3K7
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14
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Hofer I, Schimp C, Taha M, Seebach J, Aldirawi M, Cao J, Leidl Q, Ahle A, Schnittler H. Advanced Methods for the Investigation of Cell Contact Dynamics in Endothelial Cells Using Florescence-Based Live Cell Imaging. J Vasc Res 2018; 55:350-364. [DOI: 10.1159/000494933] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Accepted: 10/29/2018] [Indexed: 11/19/2022] Open
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15
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Design of a Versatile Sample Holder for Facile Culture of Cells on Electrospun Membranes or Thin Polymer Films Under Flow Conditions. Methods Mol Biol 2018. [PMID: 30539347 DOI: 10.1007/7651_2018_192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
Endothelial cell culture under flow, to mimic physiological conditions within blood vessels, has gained particular attention for the formation of a homogeneous endothelium in vitro. Here, we report on the design of a setup for simultaneous culture of up to nine electrospun membranes or thin polymer films in custom-made holders under flow on an orbital shaker. The versatile design of the device allows for the use of electrospun membranes/polymer films of choice and subsequent analysis with commonly used methods such as immunofluorescence or scanning electron microscopy.
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16
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Ghim M, Pang KT, Arshad M, Wang X, Weinberg PD. A novel method for segmenting growth of cells in sheared endothelial culture reveals the secretion of an anti-inflammatory mediator. J Biol Eng 2018; 12:15. [PMID: 30127849 PMCID: PMC6092814 DOI: 10.1186/s13036-018-0107-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Accepted: 07/06/2018] [Indexed: 11/25/2022] Open
Abstract
Background Effects of shear stress on endothelium are important for the normal physiology of blood vessels and are implicated in the pathogenesis of atherosclerosis. They have been extensively studied in vitro. In one paradigm, endothelial cells are cultured in devices that produce spatially varying shear stress profiles, and the local profile is compared with the properties of cells at the same position. A flaw in this class of experiments is that cells exposed to a certain shear profile in one location may release mediators into the medium that alter the behaviour of cells at another location, experiencing different shear, thus obscuring or corrupting the true relation between shear and cell properties. Methods Surface coating methods were developed for attaching cells only to some areas of culture-ware and preventing them from spreading into other regions even during prolonged culture. Results Segmenting the growth of cells had no effect on cell shape, alignment and number per unit area compared to culturing cells in the whole well, but there were differences in tumour-necrosis-factor-α (TNF-α)-induced expression of vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1), and monocyte adherence to the monolayer. Conclusions The results are consistent with the release of a mediator from cells exposed to high-magnitude uniaxial shear stress that has anti-inflammatory effects on activated endothelium; the mediator may be of importance in atherogenesis. Hence the new methods revealed an important property that would not have been observed without growth segmentation, suggesting that they could find more widespread application.
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Affiliation(s)
- Mean Ghim
- 1Department of Bioengineering, Imperial College London, London, SW7 2AZ UK
| | - Kuin T Pang
- 1Department of Bioengineering, Imperial College London, London, SW7 2AZ UK.,2Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (ASTAR), 61 Biopolis Drive, Singapore, 138673 Republic of Singapore
| | - Mehwish Arshad
- 1Department of Bioengineering, Imperial College London, London, SW7 2AZ UK
| | - Xiaomeng Wang
- 2Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (ASTAR), 61 Biopolis Drive, Singapore, 138673 Republic of Singapore.,3Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, 59 Nanyang Drive, Singapore, 636921 Republic of Singapore.,4Institute of Ophthalmology, University College London, EC1V 9EL, London, UK.,Singapore Eye Research Institute, The Academia, 20 College Road Discovery Tower Level 6, Singapore, 169856 Republic of Singapore
| | - Peter D Weinberg
- 1Department of Bioengineering, Imperial College London, London, SW7 2AZ UK
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17
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Spanier B, Rohm F. Proton Coupled Oligopeptide Transporter 1 (PepT1) Function, Regulation, and Influence on the Intestinal Homeostasis. Compr Physiol 2018; 8:843-869. [DOI: 10.1002/cphy.c170038] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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18
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Stelzl T, Geillinger-Kästle KE, Stolz J, Daniel H. Glycans in the intestinal peptide transporter PEPT1 contribute to function and protect from proteolysis. Am J Physiol Gastrointest Liver Physiol 2017; 312:G580-G591. [PMID: 28336547 DOI: 10.1152/ajpgi.00343.2016] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Revised: 03/16/2017] [Accepted: 03/17/2017] [Indexed: 01/31/2023]
Abstract
Despite the fact that many membrane proteins carry extracellular glycans, little is known about whether the glycan chains also affect protein function. We recently demonstrated that the proton-coupled oligopeptide transporter 1 (PEPT1) in the intestine is glycosylated at six asparagine residues (N50, N406, N439, N510, N515, and N532). Mutagenesis-induced disruption of the individual N-glycosylation site N50, which is highly conserved among mammals, was detected to significantly enhance the PEPT1-mediated inward transport of peptides. Here, we show that for the murine protein the inhibition of glycosylation at sequon N50 by substituting N50 with glutamine, lysine, or cysteine or by replacing S52 with alanine equally altered PEPT1 transport kinetics in oocytes. Furthermore, we provide evidence that the uptake of [14C]glycyl-sarcosine in immortalized murine small intestinal (MODE-K) or colonic epithelial (PTK-6) cells stably expressing the PEPT1 transporter N50Q is also significantly increased relative to the wild-type protein. By using electrophysiological recordings and tracer flux studies, we further demonstrate that the rise in transport velocity observed for PEPT1 N50Q is bidirectional. In line with these findings, we show that attachment of biotin derivatives, comparable in weight with two to four monosaccharides, to the PEPT1 N50C transporter slows down the transport velocity. In addition, our experiments provide strong evidence that glycosylation of PEPT1 confers resistance against proteolytic cleavage by proteinase K, whereas a remarkable intrinsic stability against trypsin, even in the absence of N-linked glycans, was detected.NEW & NOTEWORTHY This study highlights the role of N50-linked glycans in modulating the bidirectional transport activity of the murine peptide transporter PEPT1. Electrophysiological and tracer flux measurements in Xenopus oocytes have shown that removal of the N50 glycans increases the maximal peptide transport rate in the inward and outward directions. This effect could be largely reversed by replacement of N50 glycans with structurally dissimilar biotin derivatives. In addition, N-glycans were detected to stabilize PEPT1 against proteolytic cleavage.
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Affiliation(s)
- Tamara Stelzl
- Nutritional Physiology, Technische Universität München, Freising, Germany
| | | | - Jürgen Stolz
- Nutritional Physiology, Technische Universität München, Freising, Germany
| | - Hannelore Daniel
- Nutritional Physiology, Technische Universität München, Freising, Germany
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19
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Salt-induced Na+/K+-ATPase-α/β expression involves soluble adenylyl cyclase in endothelial cells. Pflugers Arch 2017; 469:1401-1412. [DOI: 10.1007/s00424-017-1999-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Revised: 04/03/2017] [Accepted: 05/15/2017] [Indexed: 12/28/2022]
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20
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Krüger-Genge A, Fuhrmann R, Jung F, Franke RP. Effects of different components of the extracellular matrix on endothelialization. Clin Hemorheol Microcirc 2016; 64:867-874. [PMID: 27935545 DOI: 10.3233/ch-168051] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The endothelialization of cardiovascular prostheses is known to improve their haemocompatibility. As such body-foreign materials often do not endothelialize spontaneously. A lot of in vitro studies are ongoing how endothelialization of biomaterials can be improved. In this study the influence of different components of a tissue-typical extracellular matrix (ECM) like laminin, fibronectin or gelatin on the formation of an endothelial cell monolayer and on the shear resistance of adherent cells on these substrates was studied.The study revealed that the density of human venous endothelial cells (HUVEC) monolayers differed markedly between cells grown on a natural ECM and cells grown on singularized components of an ECM (p < 0.001). Only HUVEC grown on laminin showed similar densities and a stress fiber pattern comparable to HUVEC grown on the ECM. HUVEC grown on gelatin- or fibronectin-coated coverslips were less firmly attached to the substrate; frequently individual HUVEC and even groups of cells detached.Concluding it seems that coating of implants with laminin supports the formation of shear resistant endothelial cell (EC) monolayer - superior to other ECM components.
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Affiliation(s)
- A Krüger-Genge
- Institute of Biomaterial Science and Berlin-Brandenburg Center for Regenerative Therapies, Helmholtz-Zentrum Geesthacht, Teltow, Germany
| | - R Fuhrmann
- Abteilung Biomaterialien, Zentralinstitut für Biomedizinische Technik, Universität Ulm, Ulm, Germany
| | - F Jung
- Institute of Biomaterial Science and Berlin-Brandenburg Center for Regenerative Therapies, Helmholtz-Zentrum Geesthacht, Teltow, Germany
| | - R P Franke
- Abteilung Biomaterialien, Zentralinstitut für Biomedizinische Technik, Universität Ulm, Ulm, Germany
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21
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Astrocytes in Migration. Neurochem Res 2016; 42:272-282. [PMID: 27837318 DOI: 10.1007/s11064-016-2089-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 10/20/2016] [Accepted: 10/21/2016] [Indexed: 12/30/2022]
Abstract
Cell migration is a fundamental phenomenon that underlies tissue morphogenesis, wound healing, immune response, and cancer metastasis. Great progresses have been made in research methodologies, with cell migration identified as a highly orchestrated process. Brain is considered the most complex organ in the human body, containing many types of neural cells with astrocytes playing crucial roles in monitoring normal functions of the central nervous system. Astrocytes are mostly quiescent under normal physiological conditions in the adult brain but become migratory after injury. Under most known pathological conditions in the brain, spinal cord and retina, astrocytes are activated and become hypertrophic, hyperplastic, and up-regulating GFAP based on the grades of severity. These three observations are the hallmark in glia scar formation-astrogliosis. The reactivation process is initiated with structural changes involving cell process migration and ended with cell migration. Detailed mechanisms in astrocyte migration have not been studied extensively and remain largely unknown. Here, we therefore attempt to review the mechanisms in migration of astrocytes.
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22
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Zhao B, Wang J, Liu L, Li X, Liu S, Xia Q, Shi J. Annexin A1 translocates to nucleus and promotes the expression of pro-inflammatory cytokines in a PKC-dependent manner after OGD/R. Sci Rep 2016; 6:27028. [PMID: 27426034 PMCID: PMC4947919 DOI: 10.1038/srep27028] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Accepted: 05/12/2016] [Indexed: 12/14/2022] Open
Abstract
Annexin A1 (ANXA1) is a protein known to have multiple roles in the regulation of inflammatory responses. In this study, we find that after oxygen glucose deprivation/reoxygenation (ODG/R) injury, activated PKC phosphorylated ANXA1 at the serine 27 residue (p27S-ANXA1), and promoted the translocation of p27S-ANXA1 to the nucleus of BV-2 microglial cells. This in turn induced BV-2 microglial cells to produce large amounts of pro-inflammatory cytokines. The phenomenon could be mimicked by either transfecting a mutant form of ANXA1 with its serine 27 residue converted to aspartic acid, S27D, or by using the PKC agonist, phorbol 12-myristate 13-acetate (PMA) in these microglial cells. In contrast, transfecting cells with an ANXA1 S27A mutant (serine 27 converted to alanine) or treating the cells with the PKC antagonist, GF103209X (GF) reversed this effet. Our study demonstrates that ANXA1 can be phosphorylated by PKC and is subsequently translocated to the nucleus of BV-2 microglial cells after OGD/R, resulting in the induction of pro-inflammatory cytokines.
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Affiliation(s)
- Baoming Zhao
- Department of Neurobiology, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan 430030, P. R. China.,Key Laboratory of Neurological Diseases of Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan 430030, P. R. China.,Institute for Brain Research, Huazhong University of Science and Technology, Wuhan 430030, Hubei Province, P. R. China
| | - Jing Wang
- Department of Neurobiology, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan 430030, P. R. China.,Clinical laboratory, Center hospital of Wuhan, Wuhan 430030, Hubei Province, P. R. China
| | - Lu Liu
- Department of Neurobiology, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan 430030, P. R. China.,Key Laboratory of Neurological Diseases of Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan 430030, P. R. China.,Institute for Brain Research, Huazhong University of Science and Technology, Wuhan 430030, Hubei Province, P. R. China
| | - Xing Li
- Department of Neurobiology, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan 430030, P. R. China.,Key Laboratory of Neurological Diseases of Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan 430030, P. R. China.,Institute for Brain Research, Huazhong University of Science and Technology, Wuhan 430030, Hubei Province, P. R. China
| | - Shuangxi Liu
- Department of Neurobiology, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan 430030, P. R. China.,Key Laboratory of Neurological Diseases of Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan 430030, P. R. China.,Institute for Brain Research, Huazhong University of Science and Technology, Wuhan 430030, Hubei Province, P. R. China
| | - Qian Xia
- Department of Neurobiology, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan 430030, P. R. China.,Key Laboratory of Neurological Diseases of Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan 430030, P. R. China.,Institute for Brain Research, Huazhong University of Science and Technology, Wuhan 430030, Hubei Province, P. R. China
| | - Jing Shi
- Department of Neurobiology, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan 430030, P. R. China.,Key Laboratory of Neurological Diseases of Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, 13 Hangkong Road, Wuhan 430030, P. R. China.,Institute for Brain Research, Huazhong University of Science and Technology, Wuhan 430030, Hubei Province, P. R. China
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Avari H, Savory E, Rogers KA. An In Vitro Hemodynamic Flow System to Study the Effects of Quantified Shear Stresses on Endothelial Cells. Cardiovasc Eng Technol 2015; 7:44-57. [PMID: 26621672 DOI: 10.1007/s13239-015-0250-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Accepted: 11/20/2015] [Indexed: 11/27/2022]
Abstract
Numerous in vitro systems have previously been developed and employed for studying the effects of hemodynamics on endothelial cell (EC) dysfunction. In the majority of that work, accurate flow quantification (e.g., uniformity of the flow over the ECs) remains elusive and wall shear stress (WSS) quantifications are determined using theoretical relationships (without considering the flow channel aspect ratio effects). In addition, those relationships are not applicable to flows other than steady laminar cases. The present work discusses the development of a novel hemodynamic flow system for studying the effects of various well-quantified flow regimes over ECs. The current work presents a novel hemodynamic flow system applying the concept of a parallel plate flow chamber (PPFC) with live microscopy access for studying the effects of quantified WSS on ECs. A range of steady laminar, pulsatile (carotid wave form) and low-Reynolds number turbulent WSSs were quantified through velocity field measurements by a laser Doppler velocimetry (LDV) system, to validate the functionality of the current hemodynamic flow system. Uniformity of the flow across the channel width can be analyzed with the current system (e.g., the flow was uniform across about 65-75% of the channel width for the steady cases). The WSS obtained from the experiments had higher values in almost all of the cases when compared to the most commonly-used theoretical solution (9% < error < 16%), whereas another relationship, which considers the channel dimensions, had better agreement with the experimental results (1% < error < 8%). Additionally, the latter relationship predicted the uniform flow region in the PPFC with an average difference of <5% when compared to the experimental results. The experimental data also showed that the WSS at various locations (D, E and F) at the test section differed by less than 4% for the laminar cases representing a fully developed flow. WSS was also determined for a low-Re (Re = 2750) turbulent flow using (1) the Reynolds shears stress and (2) the time-averaged velocity profile gradient at the wall, with a good agreement (differences <16%) between the two where the first method returned a higher value than the second. Porcine aortic endothelial cell (PAEC) viability in the system and morphological cell response to laminar WSS of about 11 dyne/cm(2), were observed. These results provide performance validation of this novel in vitro system with many improved features compared to previous similar prototypes for investigation of flow effects on ECs. The integration of the LDV technique in the current study and the comparison of the results with those from theory revealed that great care must be taken when using PPFCs since the commonly used theoretical relation for laminar steady flows is unable to predict the flow uniformity (which may introduce significant statistical bias in biological studies) and the predicted WSS was subjected to greater error when compared to a more comprehensive equation presented in the current work. Moreover, application of the LDV technique in the current system is essential for studies of more complex cases, such as disturbed flows, where the WSS cannot be predicted using theoretical or numerical modelling methods.
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Affiliation(s)
- Hamed Avari
- Advanced Fluid Mechanics Research Group, Department of Mechanical and Materials Engineering, University of Western Ontario, London, ON, N6A 5B8, Canada.
| | - Eric Savory
- Advanced Fluid Mechanics Research Group, Department of Mechanical and Materials Engineering, University of Western Ontario, London, ON, N6A 5B8, Canada.
| | - Kem A Rogers
- Department of Anatomy and Cell Biology, University of Western Ontario, London, ON, N6A 5B8, Canada.
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24
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Filipovic N, Ghimire K, Saveljic I, Milosevic Z, Ruegg C. Computational modeling of shear forces and experimental validation of endothelial cell responses in an orbital well shaker system. Comput Methods Biomech Biomed Engin 2015; 19:581-90. [DOI: 10.1080/10255842.2015.1051973] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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25
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Davis CA, Zambrano S, Anumolu P, Allen ACB, Sonoqui L, Moreno MR. Device-Based In Vitro Techniques for Mechanical Stimulation of Vascular Cells: A Review. J Biomech Eng 2015; 137:040801. [DOI: 10.1115/1.4029016] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Accepted: 11/07/2014] [Indexed: 01/19/2023]
Abstract
The most common cause of death in the developed world is cardiovascular disease. For decades, this has provided a powerful motivation to study the effects of mechanical forces on vascular cells in a controlled setting, since these cells have been implicated in the development of disease. Early efforts in the 1970 s included the first use of a parallel-plate flow system to apply shear stress to endothelial cells (ECs) and the development of uniaxial substrate stretching techniques (Krueger et al., 1971, “An in Vitro Study of Flow Response by Cells,” J. Biomech., 4(1), pp. 31–36 and Meikle et al., 1979, “Rabbit Cranial Sutures in Vitro: A New Experimental Model for Studying the Response of Fibrous Joints to Mechanical Stress,” Calcif. Tissue Int., 28(2), pp. 13–144). Since then, a multitude of in vitro devices have been designed and developed for mechanical stimulation of vascular cells and tissues in an effort to better understand their response to in vivo physiologic mechanical conditions. This article reviews the functional attributes of mechanical bioreactors developed in the 21st century, including their major advantages and disadvantages. Each of these systems has been categorized in terms of their primary loading modality: fluid shear stress (FSS), substrate distention, combined distention and fluid shear, or other applied forces. The goal of this article is to provide researchers with a survey of useful methodologies that can be adapted to studies in this area, and to clarify future possibilities for improved research methods.
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Affiliation(s)
- Caleb A. Davis
- Department of Biomedical Engineering, Texas A&M University, College Station, TX 77843-3120 e-mail:
| | - Steve Zambrano
- Department of Biomedical Engineering, Texas A&M University, College Station, TX 77843-3120 e-mail:
| | - Pratima Anumolu
- Department of Biomedical Engineering, Texas A&M University, College Station, TX 77843-3120 e-mail:
| | - Alicia C. B. Allen
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78712-1801 e-mail:
| | - Leonardo Sonoqui
- Department of Biomedical Engineering, Texas A&M University, College Station, TX 77843-3120 e-mail:
| | - Michael R. Moreno
- Department of Mechanical Engineering, Department of Biomedical Engineering, Texas A&M University, College Station, TX 77843-3123 e-mail:
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Transepithelial Transport Characteristics of the Antihypertensive Peptide, Lys-Val-Leu-Pro-Val-Pro, in Human Intestinal Caco-2 Cell Monolayers. Biosci Biotechnol Biochem 2014; 73:293-8. [DOI: 10.1271/bbb.80473] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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27
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Potent stimulation of blood flow in fingers of volunteers after local short-term treatment with low-frequency magnetic fields from a novel device. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2014; 2014:543564. [PMID: 24963323 PMCID: PMC4055403 DOI: 10.1155/2014/543564] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Revised: 02/27/2014] [Accepted: 03/10/2014] [Indexed: 11/17/2022]
Abstract
A novel hand-held low-frequency magnetic stimulator (MagCell-SR) was tested for its ability to stimulate microcirculation in fingers of healthy volunteers. Blood flow during and after 5 minutes exposure was quantified using Laser Doppler Perfusion Imaging Technique. The device was positioned between the wrist and the dorsal part of the backhand. Because the increase in blood flow could be caused by a release of nitric oxide (NO) from the vascular endothelial cells we tested NO production with a fluorescence marker and quantified the measurements in cell cultures of human umbilical endothelial cells (HUVEC). Exposure increased blood flow significantly, persisted several minutes, and then disappeared gradually. In order to assess the effect of a static magnetic field, the measurements were also carried out with the device shutoff. Here, only a small increase in blood flow was noted. The application of the rotating MagCell-SR to the HUVEC cultures leads to a rapid onset and a significant increase of NO release after 15 minutes. Thus, frequencies between 4 and 12 Hz supplied by the device improve microcirculation significantly. Therefore, this device can be used in all clinical situations where an improvement of the microcirculation is useful like in chronic wound healing deficits.
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Experimental tools to monitor the dynamics of endothelial barrier function: a survey of in vitro approaches. Cell Tissue Res 2014; 355:485-514. [DOI: 10.1007/s00441-014-1810-3] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Accepted: 01/13/2014] [Indexed: 02/05/2023]
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29
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Time-dependent adhesive interaction of osteoblastic cells with polished titanium alloyed implant surfaces. J Appl Biomater Funct Mater 2013; 11:e1-8. [PMID: 22798245 DOI: 10.5301/jabfm.2012.9263] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/20/2011] [Indexed: 01/24/2023] Open
Abstract
AIM Design optimization and surface modifications of orthopedic implants are focused on adhesive properties depending on specific applications. To obtain an in-vitro understanding of the adhesion interaction of bone cells on implant surfaces the time-dependent adhesion behavior of osteoblastic cells was studied. MATERIALS AND METHODS MG-63 osteoblastic cells were seeded on discs of polished titanium alloy (Ti6Al4V) and allowed to adhere for various time periods (1 to 48 h). Using a spinning disc device and a confocal laser scanning microscope (LSM) the shear stress required to detach the bone cells from the substrate was determined. An approximation of the adhesion force was calculated from measurements of cell height and contact radius. RESULTS Shear stress ranged from 40.4 N/m2 to 82.4 N/m2 showing an increase in cell adhesion reaching a maximum after 6 h before decreasing significantly. Using the cell height and contact radii, measured for the various time periods, the lowest adhesion force of 232 nN was approximated after 1 h cell adhesion and analogous to the adhesion strength measurements, the highest of 664 nN after 6 h. Generally, cell adhesion decreased at incubation times longer than 6 h before an increase after 48 h was observed once again. CONCLUSIONS Differences in adhesion behavior over time indicate dynamic cell-substrate interactions because of cell migration and proliferation processes. The study stresses the importance of calculating the adhesion force rather than shear stress to gain more expressive data regarding cell adhesion.
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Leong CM, Voorhees A, Nackman GB, Wei T. Flow bioreactor design for quantitative measurements over endothelial cells using micro-particle image velocimetry. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2013; 84:045109. [PMID: 23635234 DOI: 10.1063/1.4802681] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Mechanotransduction in endothelial cells (ECs) is a highly complex process through which cells respond to changes in hemodynamic loading by generating biochemical signals involving gene and protein expression. To study the effects of mechanical loading on ECs in a controlled fashion, different in vitro devices have been designed to simulate or replicate various aspects of these physiological phenomena. This paper describes the design, use, and validation of a flow chamber which allows for spatially and temporally resolved micro-particle image velocimetry measurements of endothelial surface topography and stresses over living ECs immersed in pulsatile flow. This flow chamber also allows the study of co-cultures (i.e., ECs and smooth muscle cells) and the effect of different substrates (i.e., coverslip and∕or polyethylene terepthalate (PET) membrane) on cellular response. In this report, the results of steady and pulsatile flow on fixed endothelial cells seeded on PET membrane and coverslip, respectively, are presented. Surface topography of ECs is computed from multiple two-dimensional flow measurements. The distributions of shear stress and wall pressure on each individual cell are also determined and the importance of both types of stress in cell remodeling is highlighted.
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Affiliation(s)
- Chia Min Leong
- Department of Mechanical, Aerospace and Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180, USA.
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31
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Spruell C, Baker AB. Analysis of a high-throughput cone-and-plate apparatus for the application of defined spatiotemporal flow to cultured cells. Biotechnol Bioeng 2013; 110:1782-93. [PMID: 23280552 DOI: 10.1002/bit.24823] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Revised: 11/28/2012] [Accepted: 12/11/2012] [Indexed: 01/09/2023]
Abstract
The shear stresses derived from blood flow regulate many aspects of vascular and immunobiology. In vitro studies on the shear stress-mediated mechanobiology of endothelial cells have been carried out using systems analogous to the cone-and-plate viscometer in which a rotating, low-angle cone applies fluid shear stress to cells grown on an underlying, flat culture surface. We recently developed a device that could perform high-throughput studies on shear-mediated mechanobiology through the rotation of cone-tipped shafts in a standard 96-well culture plate. Here, we present a model of the three-dimensional flow within the culture wells with a rotating, cone-tipped shaft. Using this model we examined the effects of modifying the design parameters of the system to allow the device to create a variety of flow profiles. We first examined the case of steady-state flow with the shaft rotating at constant angular velocity. By varying the angular velocity and distance of the cone from the underlying plate we were able to create flow profiles with controlled shear stress gradients in the radial direction within the plate. These findings indicate that both linear and non-linear spatial distributions in shear stress can be created across the bottom of the culture plate. In the transition and "parallel shaft" regions of the system, the angular velocities needed to provide high levels of physiological shear stress (5 Pa) created intermediate Reynolds number Taylor-Couette flow. In some cases, this led to the development of a flow regime in which stable helical vortices were created within the well. We also examined the system under oscillatory and pulsatile motion of the shaft and demonstrated minimal time lag between the rotation of the cone and the shear stress on the cell culture surface.
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Affiliation(s)
- Christopher Spruell
- Department of Biomedical Engineering, University of Texas at Austin, 1 University Station, BME 5.202D, C0800, Austin, Texas 78712, USA
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32
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Lu L, Mende M, Yang X, Körber HF, Schnittler HJ, Weinert S, Heubach J, Werner C, Ravens U. Design and validation of a bioreactor for simulating the cardiac niche: a system incorporating cyclic stretch, electrical stimulation, and constant perfusion. Tissue Eng Part A 2012; 19:403-14. [PMID: 22991978 DOI: 10.1089/ten.tea.2012.0135] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
To simulate the cardiac niche, a bioreactor system was designed and constructed to incorporate cyclic stretch, rhythmic electrical stimulation, and constant perfusion. The homogeneity of surface strain distribution across the cell culture substrate was confirmed with ARAMIS deformation analysis. The proliferation marker, Ki-67, detected in human umbilical vein endothelial cells and 3-[4,5-dimethyl-thiazol-2-yl]-2,5-diphenyltetrazolium bromide cytotoxicity assay performed on human atrial fibroblasts confirmed biocompatibility of this novel device. Cyclic stretch treatment for 24 h resulted in the perpendicular alignment of human atrial fibroblasts. An electrical stimulation system containing carbon electrodes was characterized by electrochemical impedance spectroscopy and charge injection/recovery studies, which indicated that increased corrosive reactions were associated with a higher input voltage and prolonged pulse duration. Field stimulation delivered through this system could induce rhythmic contractions in adult rat ventricular myocytes, with contractile characteristics similar to those paced in a standard field stimulation chamber. In conclusion, this bioreactor provides a novel tool to study the interaction between physical stimulation and cardiac cell physiology.
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Affiliation(s)
- Liang Lu
- Department of Pharmacology and Toxicology, Medical Faculty Carl Gustav Carus, Dresden University of Technology, Dresden, Germany
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Abstract
Throughout their lives, all cells constantly experience and respond to various mechanical forces. These frequently originate externally but can also arise internally as a result of the contractile actin cytoskeleton. Mechanical forces trigger multiple signaling pathways. Several converge and result in the activation of the GTPase RhoA. In this review, we focus on the pathways by which mechanical force leads to RhoA regulation, especially when force is transmitted via cell adhesion molecules that mediate either cell-matrix or cell-cell interactions. We discuss both the upstream signaling events that lead to activation of RhoA and the downstream consequences of this pathway. These include not only cytoskeletal reorganization and, in a positive feedback loop, increased myosin-generated contraction but also profound effects on gene expression and differentiation.
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Affiliation(s)
- Elizabeth C Lessey
- Department of Cell Biology and Physiology, University of North Carolina, Chapel Hill, NC 27599, USA
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Teichmann J, Morgenstern A, Seebach J, Schnittler HJ, Werner C, Pompe T. The control of endothelial cell adhesion and migration by shear stress and matrix-substrate anchorage. Biomaterials 2011; 33:1959-69. [PMID: 22154622 DOI: 10.1016/j.biomaterials.2011.11.017] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2011] [Accepted: 11/10/2011] [Indexed: 10/14/2022]
Abstract
Endothelial cells constitute the natural inner lining of blood vessels and possess anti-thrombogenic properties. This characteristic is frequently used by seeding endothelial cells on vascular prostheses. As the type of anchorage of adhesion ligands to materials surfaces is known to determine the mechanical balance of adherent cells, we investigated herein the behaviour of endothelial cells under physiological shear stress conditions. The adhesion ligand fibronectin was anchored to polymer surfaces of four physicochemical characteristics exhibiting covalent and non-covalent attachment as well as high and low hydrophobicity. The in situ analysis combined with cell tracking of shear stress-induced effects on cultured isolated cells and monolayers under venous (0.5 dyn/cm(2)) and arterial (12 dyn/cm(2)) shear stress over a time period of 24 h revealed distinct differences in their morphological and migratory features. Most pronounced, unidirectional and bimodal migration patterns of endothelial cells in or against flow direction were found in dependence on the type of substrate-matrix anchorage. Combined by an immunofluorescent analysis of the actin cytoskeleton, cell-cell junctions, cell-matrix adhesions, and matrix reorganization these results revealed a distinct balance of laminar shear stress, cell-cell contacts and substrate-matrix anchorage in affecting endothelial cell fate under flow conditions. This analysis underlines the importance of materials surface parameters as well as primary and secondary adhesion ligand anchorage in the context of artificial blood vessels for future therapeutic devices.
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Affiliation(s)
- Juliane Teichmann
- Leibniz Institute of Polymer Research Dresden, Max Bergmann Center of Biomaterials Dresden, Hohe Strasse 6, 01069 Dresden, Germany
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Rezvan A, Ni CW, Alberts-Grill N, Jo H. Animal, in vitro, and ex vivo models of flow-dependent atherosclerosis: role of oxidative stress. Antioxid Redox Signal 2011; 15:1433-48. [PMID: 20712399 PMCID: PMC3144429 DOI: 10.1089/ars.2010.3365] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Atherosclerosis is an inflammatory disease preferentially occurring in curved or branched arterial regions, whereas straight parts of the arteries are protected, suggesting a close relationship between flow and atherosclerosis. However, evidence directly linking disturbed flow to atherogenesis is just emerging, thanks to the recent development of suitable animal models. In this article, we review the status of various animal, in vitro, and ex vivo models that have been used to study flow-dependent vascular biology and atherosclerosis. For animal models, naturally flow-disturbed regions such as branched or curved arterial regions as well as surgically created models, including arterio-venous fistulas, vascular grafts, perivascular cuffs, and complete, incomplete, or partial ligation of arteries, are used. Although in vivo models provide the environment needed to mimic the complex pathophysiological processes, in vitro models provide simple conditions that allow the study of isolated factors. Typical in vitro models use cultured endothelial cells exposed to various flow conditions, using devices such as cone-and-plate and parallel-plate chambers. Ex vivo models using isolated vessels have been used to bridge the gap between complex in vivo models and simple in vitro systems. Here, we review these flow models in the context of the role of oxidative stress in flow-dependent inflammation, a critical proatherogenic step, and atherosclerosis.
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Affiliation(s)
- Amir Rezvan
- Division of Cardiology, Department of Medicine, Emory University, Atlanta, Georgia 30322, USA
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36
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Dietrich M, Bartfeld S, Munke R, Lange C, Ogilvie LA, Friedrich A, Meyer TF. Activation of NF-κB by Neisseria gonorrhoeae is associated with microcolony formation and type IV pilus retraction. Cell Microbiol 2011; 13:1168-82. [PMID: 21615661 DOI: 10.1111/j.1462-5822.2011.01607.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The early stage of infection with Neisseria gonorrhoeae (Ngo), the causative agent of gonorrhoea, is marked by type IV pilus (Tfp)-mediated attachment and the formation of bacterial microcolonies on epithelial cells. Retraction of the Ngo Tfp generates substantial force on its substrate which can elicit host cell signalling. Here, we observed that this retraction force could also activate nuclear factor (NF)-κB, the central signalling cascade of innate immunity. Using a p65-GFP-expressing epithelial cell line, we show that piliated Ngo induce asynchronous NF-κB activation in infected cells, which is temporally associated with the formation of gonococcal microcolonies. A mutant lacking PilT, an ATPase necessary for Tfp retraction, induced markedly reduced NF-κB activation. This was accompanied by decreased NF-κB target gene transcription and cytokine release. The impaired ability of the pilT mutant to activate NF-κB was compensated by applying mechanical shear stress to the infected host cells, indicating that the mechanical forces generated by retractile pili are involved in the retraction-dependent activation of NF-κB elicited by gonococcal microcolonies. Thus, our work provides evidence for an intriguing relationship between microcolony growth, pilus retraction and host cell signalling, with likely implications with regard to the course of symptomatic versus asymptomatic gonococcal infections.
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Affiliation(s)
- Manuela Dietrich
- Department of Molecular Biology, Max Planck Institute for Infection Biology, Berlin, Germany
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37
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Chiu JJ, Chien S. Effects of disturbed flow on vascular endothelium: pathophysiological basis and clinical perspectives. Physiol Rev 2011; 91:327-87. [PMID: 21248169 PMCID: PMC3844671 DOI: 10.1152/physrev.00047.2009] [Citation(s) in RCA: 1375] [Impact Index Per Article: 105.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Vascular endothelial cells (ECs) are exposed to hemodynamic forces, which modulate EC functions and vascular biology/pathobiology in health and disease. The flow patterns and hemodynamic forces are not uniform in the vascular system. In straight parts of the arterial tree, blood flow is generally laminar and wall shear stress is high and directed; in branches and curvatures, blood flow is disturbed with nonuniform and irregular distribution of low wall shear stress. Sustained laminar flow with high shear stress upregulates expressions of EC genes and proteins that are protective against atherosclerosis, whereas disturbed flow with associated reciprocating, low shear stress generally upregulates the EC genes and proteins that promote atherogenesis. These findings have led to the concept that the disturbed flow pattern in branch points and curvatures causes the preferential localization of atherosclerotic lesions. Disturbed flow also results in postsurgical neointimal hyperplasia and contributes to pathophysiology of clinical conditions such as in-stent restenosis, vein bypass graft failure, and transplant vasculopathy, as well as aortic valve calcification. In the venous system, disturbed flow resulting from reflux, outflow obstruction, and/or stasis leads to venous inflammation and thrombosis, and hence the development of chronic venous diseases. Understanding of the effects of disturbed flow on ECs can provide mechanistic insights into the role of complex flow patterns in pathogenesis of vascular diseases and can help to elucidate the phenotypic and functional differences between quiescent (nonatherogenic/nonthrombogenic) and activated (atherogenic/thrombogenic) ECs. This review summarizes the current knowledge on the role of disturbed flow in EC physiology and pathophysiology, as well as its clinical implications. Such information can contribute to our understanding of the etiology of lesion development in vascular niches with disturbed flow and help to generate new approaches for therapeutic interventions.
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Affiliation(s)
- Jeng-Jiann Chiu
- Division of Medical Engineering Research, National Health Research Institutes, Taiwan
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38
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Abstract
The endothelial cells lining blood vessels are continuously exposed to fluid shear stress generated by pulsatile flow of blood. In order to minimise forces acting on their surface, endothelial cells adapt to shear stress by alignment and migration within the direction of flow. Failure to adapt to shear stress results in endothelial damage contributing to generation of atherosclerotic plaques or abnormal vessel repair. This chapter describes methods of generating laminar flow in vitro and studying endothelial cell alignment and motility under flow.
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Affiliation(s)
- Beata Wojciak-Stothard
- Department of Experimental Medicine and Toxicology, Imperial College London, London, UK.
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39
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Shimizu K, Sato M, Zhang Y, Kouguchi T, Takahata Y, Morimatsu F, Shimizu M. The bioavailable octapeptide Gly-Ala-Hyp-Gly-Leu-Hyp-Gly-Pro stimulates nitric oxide synthesis in vascular endothelial cells. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2010; 58:6960-6965. [PMID: 20459131 DOI: 10.1021/jf100388w] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Gly-Ala-Hyp-Gly-Leu-Hyp-Gly-Pro (GAXGLXGP, X: Hyp), an octapeptide contained in chicken collagen hydrolysate, inhibits angiotensin I-converting enzyme activity in vitro. Intestinal Caco-2 and bovine aortic endothelial cells (BAECs) were used to investigate whether the transported GAXGLXGP improves vascular function. When GAXGLXGP was added to the apical side of Caco-2 monolayers, the intact form of GAXGLXGP was released to the basolateral side without incorporation into the cells. This transport was energy-independent but was associated with tight junction permeability. GAXGLXGP was then added to BAECs, and endothelial nitric oxide (NO) synthase (eNOS) activation was examined. GAXGLXGP at a concentration of 10 microM stimulated production of NO during a 1 h incubation. This event involved phosphorylation of eNOS at Ser(1179) without a change in the total eNOS protein level. These findings indicate that GAXGLXGP absorbed intact through the intestinal epithelium has direct effects on eNOS activity in vascular endothelial cells, leading to NO synthesis, thereby suggesting the potential for improvement in vascular function.
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Affiliation(s)
- Kazuo Shimizu
- R&D Center, Nippon Meat Packers Inc, Tsukuba, Ibaraki 300-2646, Japan.
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40
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Young EWK, Simmons CA. Macro- and microscale fluid flow systems for endothelial cell biology. LAB ON A CHIP 2010; 10:143-60. [PMID: 20066241 DOI: 10.1039/b913390a] [Citation(s) in RCA: 147] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Recent advances in microfluidics have brought forth new tools for studying flow-induced effects on mammalian cells, with important applications in cardiovascular, bone and cancer biology. The plethora of microscale systems developed to date demonstrate the flexibility of microfluidic designs, and showcase advantages of the microscale that are simply not available at the macroscale. However, the majority of these systems will likely not achieve widespread use in the biological laboratory due to their complexity and lack of user-friendliness. To gain widespread acceptance in the biological research community, microfluidics engineers must understand the needs of cell biologists, while biologists must be made aware of available technology. This review provides a critical evaluation of cell culture flow (CCF) systems used to study the effects of mechanical forces on endothelial cells (ECs) in vitro. To help understand the need for various designs of CCF systems, we first briefly summarize main properties of ECs and their native environments. Basic principles of various macro- and microscale systems are described and evaluated. New opportunities are uncovered for developing technologies that have potential to both improve efficiency of experimentation as well as answer important biological questions that otherwise cannot be tackled with existing systems. Finally, we discuss some of the unresolved issues related to microfluidic cell culture, suggest possible avenues of investigation that could resolve these issues, and provide an outlook for the future of microfluidics in biological research.
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Affiliation(s)
- Edmond W K Young
- Department of Biomedical Engineering, Wisconsin Institutes for Medical Research, University of Wisconsin-Madison, 1111 Highland Avenue, Madison, WI 53705, USA.
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O'Keeffe LM, Muir G, Piterina AV, McGloughlin T. Vascular cell adhesion molecule-1 expression in endothelial cells exposed to physiological coronary wall shear stresses. J Biomech Eng 2009; 131:081003. [PMID: 19604015 DOI: 10.1115/1.3148191] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Atherosclerosis is consistently found in bifurcations and curved segments of the circulatory system, indicating disturbed hemodynamics may participate in disease development. In vivo and in vitro studies have shown that endothelial cells (ECs) alter their gene expression in response to their hemodynamic environment, in a manner that is highly dependent on the exact nature of the applied forces. This research exposes cultured ECs to flow patterns present in the coronary arterial network, in order to determine the role of hemodynamic forces in plaque initiation. Vascular cell adhesion molecule-1 (VCAM-1) was examined as an indicator of plaque growth, as it participates in monocyte adhesion, which is one of the initial steps in the formation of fatty lesions. The hemodynamics of a healthy right and left coronary artery were determined by reconstructing 3D models from cineangiograms and employing computational fluid dynamic models to establish physiological coronary flow patterns. Wall shear stress (WSS) profiles selected from these studies were applied to ECs in a cone and plate bioreactor. The cone and plate system was specifically designed to be capable of reproducing the high frequency harmonics present in physiological waveforms. The shear stresses chosen represent those from regions prone to disease development and healthier arterial segments. The levels of the transcriptional and cell surface anchored VCAM-1 were quantified by flow cytometry and real time RT-PCR over a number of timepoints to obtain a complete picture of the relationship between this adhesion molecule and the applied shear stress. The WSS profiles from regions consistently displaying a higher incidence of plaques in vivo, induced greater levels of VCAM-1, particularly at the earlier timepoints. Conversely, the WSS profile from a straight section of vessel with undisturbed flow indicated no upregulation in VCAM-1 and a significant downregulation after 24 h, when compared with static controls. Low shear stress from the outer wall of a bifurcation induced four times the levels of VCAM-1 messenger ribonucleic acid (mRNA) after four hours when compared with levels of mRNA induced by WSS from a straight arterial section. This shear profile also induced prolonged expression of the surface protein of this molecule. The current study has provided insight into the possible influences of coronary hemodynamics on plaque localization, with VCAM-1 only significantly induced by the WSS from disease prone regions.
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Affiliation(s)
- Lucy M O'Keeffe
- Centre for Applied Biomedical Engineering Research, Materials and Surface Science Institute, University of Limerick, Castletroy, Limerick, Ireland
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Fujimoto H, Higuchi M, Watanabe H, Koh Y, Ghosh AK, Mitsuya H, Tanoue N, Hamada A, Saito H. P-glycoprotein mediates efflux transport of darunavir in human intestinal Caco-2 and ABCB1 gene-transfected renal LLC-PK1 cell lines. Biol Pharm Bull 2009; 32:1588-1593. [PMID: 19721237 PMCID: PMC6526530 DOI: 10.1248/bpb.32.1588] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/29/2023]
Abstract
Darunavir (DRV) is a nonpeptidic protease inhibitor (PI) approved for the treatment of human immunodeficiency virus (HIV) infection. DRV displays potent activity against HIV strains resistant to other available PIs. Coadministration with ritonavir (RTV) improves the oral bioavailability of DRV. Inhibition of cytochrome P450 by RTV has been proposed as a mechanism for enhanced DRV bioavailability. However, interaction of these drugs with intestinal transporters has not been elucidated. This study was performed to explore the involvement of P-glycoprotein in transcellular DRV transport in monolayers of human intestinal Caco-2 and in ABCB1 multidrug resistance 1, (MDR1) gene-transfected renal LLC-PK1 (L-MDR1) cell lines. Transepithelial transport of DRV in Caco-2 cell monolayers was 2-fold greater in the basal-to-apical direction compared to that in the opposite direction. RTV had a significant inhibitory effect on the efflux transport of DRV in Caco-2 cells. The apical-to-basal DRV transport was enhanced by P-glycoprotein inhibitors, cyclosporin A and verapamil, as well as multidrug resistance-related protein (MRP/ABCC) inhibitors, probenecid and MK571. Using the L-MDR1 cell line, basal-to-apical DRV transport was much greater than in the opposite direction. Furthermore, cyclosporin A markedly inhibited the basal-to-apical DRV transport. RTV significantly increased the apical-to-basal transport of DRV in L-MDR1 cells, but reduced transport in the opposite direction. DRV inhibited P-glycoprotein-mediated efflux of calcein-acetoxymethyl ester in L-MDR1 cells with the inhibitory potency of 121 microM. These findings suggest that DRV is a substrate of P-glycoprotein and MRP, most likely MRP2. RTV appeared to inhibit P-glycoprotein, thereby enhancing the absorptive transport of DRV.
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MESH Headings
- ATP Binding Cassette Transporter, Subfamily B
- ATP Binding Cassette Transporter, Subfamily B, Member 1/antagonists & inhibitors
- ATP Binding Cassette Transporter, Subfamily B, Member 1/genetics
- ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism
- ATP Binding Cassette Transporter, Subfamily B, Member 1/physiology
- Animals
- Biological Transport, Active/drug effects
- Biological Transport, Active/physiology
- Caco-2 Cells
- Darunavir
- Down-Regulation/drug effects
- Down-Regulation/physiology
- Humans
- Intestinal Mucosa/cytology
- Intestinal Mucosa/drug effects
- Intestinal Mucosa/metabolism
- Kidney/cytology
- Kidney/drug effects
- Kidney/metabolism
- LLC-PK1 Cells
- Sulfonamides/metabolism
- Swine
- Transfection/methods
- Up-Regulation/drug effects
- Up-Regulation/physiology
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Affiliation(s)
| | - Maiko Higuchi
- Department of Pharmacy, Kumamoto University Hospital
| | | | - Yasuhiro Koh
- Department of Hematology, Kumamoto University Graduate School of Medical and Pharmaceutical Sciences, Kumamoto University; 1–1–1 Honjo, Kumamoto 860–8556, Japan
| | - Arun K. Ghosh
- Departments of Chemistry and Medicinal Chemistry, Purdue University; West Lafayette, Indiana 47907, U.S.A
| | - Hiroaki Mitsuya
- Department of Hematology, Kumamoto University Graduate School of Medical and Pharmaceutical Sciences, Kumamoto University; 1–1–1 Honjo, Kumamoto 860–8556, Japan
| | - Naomi Tanoue
- Department of Pharmacy, Kumamoto University Hospital
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Fliegel L. Regulation of the Na+/H+exchanger in the healthy and diseased myocardium. Expert Opin Ther Targets 2008; 13:55-68. [PMID: 19063706 DOI: 10.1517/14728220802600707] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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44
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Smith PL, Eddy EP, Lee CP, Wilson G. Exploitation of the Intestinal Oligopeptide Transporter to Enhance Drug Absorption. Drug Deliv 2008. [DOI: 10.3109/10717549309022763] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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45
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Smith PL, Eddy EP, Lee CP, Wilson G. Exploitation of the intestinal oligopeptide transporter to enhance drug absorption. Drug Deliv 2008. [DOI: 10.3109/10717549609031181] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Girdhar G, Bluestein D. Biological effects of dynamic shear stress in cardiovascular pathologies and devices. Expert Rev Med Devices 2008; 5:167-81. [PMID: 18331179 PMCID: PMC2865252 DOI: 10.1586/17434440.5.2.167] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Altered and highly dynamic shear stress conditions have been implicated in endothelial dysfunction leading to cardiovascular disease, and in thromboembolic complications in prosthetic cardiovascular devices. In addition to vascular damage, the pathological flow patterns characterizing cardiovascular pathologies and blood flow in prosthetic devices induce shear activation and damage to blood constituents. Investigation of the specific and accentuated effects of such flow-induced perturbations on individual cell-types in vitro is critical for the optimization of device design, whereby specific design modifications can be made to minimize such perturbations. Such effects are also critical in understanding the development of cardiovascular disease. This review addresses limitations to replicate such dynamic flow conditions in vitro and also introduces the idea of modified in vitro devices, one of which is developed in the authors' laboratory, with dynamic capabilities to investigate the aforementioned effects in greater detail.
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Affiliation(s)
- Gaurav Girdhar
- Department of Biomedical Engineering, State University of New York at Stony Brook, Stony Brook, NY 11794-8181, USA.
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Goettsch W, Gryczka C, Korff T, Ernst E, Goettsch C, Seebach J, Schnittler HJ, Augustin HG, Morawietz H. Flow-dependent regulation of angiopoietin-2. J Cell Physiol 2007; 214:491-503. [PMID: 17960565 DOI: 10.1002/jcp.21229] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Endothelial cells are constantly exposed to high or low shear stress in arteries and veins by the flowing blood. Angiopoietin-2 (Ang-2) is acting as a critical regulator of vessel maturation and endothelial cell quiescence. In this study, flow-dependent regulation of Ang-2 was analyzed in vitro and in vivo. Ang-2 mRNA, protein expression and release was upregulated by 24 h of low (1 dyne/cm(2)), but downregulated by high flow (30 dyne/cm(2)) in human endothelial cells. Increased endothelial NO synthase expression and NO formation was not affecting regulation of Ang-2 by low or high flow. Low and high flow increased VEGF-A expression. Inhibition of VEGFR-2 prevented upregulation of Ang-2 by low flow, but not downregulation of Ang-2 by high flow. Furthermore, upregulation of Ang-2 by VEGF was reduced by application of high flow. Forkhead box O (FOXO) transcription factor FOXO1 has been shown to regulate Ang-2 expression in endothelial cells. FOXO1 binding activity was reduced by high flow. Nuclear localization of transcription factor FOXO1 was not changed by low flow, but reduced by high flow. In vivo, Ang-2 was higher expressed in veins compared to arteries. Arterial ligation augmented Ang-2 expression in distal arterial low flow areas. Our results support a VEGF-dependent induction of Ang-2 in low flow areas, and FOXO1-dependent downregulation of Ang-2 in high flow areas. These data suggest a new mechanism of flow-dependent regulation of vessel stability and differentiation.
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Affiliation(s)
- Winfried Goettsch
- Department of Vascular Endothelium and Microcirculation, University of Technology, Dresden, Germany
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Baumer Y, Burger S, Curry FE, Golenhofen N, Drenckhahn D, Waschke J. Differential role of Rho GTPases in endothelial barrier regulation dependent on endothelial cell origin. Histochem Cell Biol 2007; 129:179-91. [DOI: 10.1007/s00418-007-0358-7] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/01/2007] [Indexed: 01/22/2023]
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Wang CX, Shuaib A. Critical role of microvasculature basal lamina in ischemic brain injury. Prog Neurobiol 2007; 83:140-8. [PMID: 17868971 DOI: 10.1016/j.pneurobio.2007.07.006] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2007] [Revised: 06/05/2007] [Accepted: 07/26/2007] [Indexed: 11/19/2022]
Abstract
Cerebral vascular system can be divided into two categories: the macrovessels and microvessels. The microvessels consist of arterioles, capillaries and venules. There are three basic components in the microvasculature: endothelial cells, basal lamina and end-feet of astrocytes. The basal lamina is situated between the endothelial cells and the end-feet of astrocytes, and connects these two layers together. Damage to the basal lamina causes the dismantlement of microvascular wall structures, which in turn results in increase of microvascular permeability, hemorrhagic transformation, brain edema and compromise of the microcirculation. The present article reviews microvascular changes during ischemic brain injury, with emphasis on basal lamina damage.
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Affiliation(s)
- Chen Xu Wang
- Stroke Research Laboratory, University of Alberta, Edmonton, Canada.
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Abstract
Absorption enhancers have been investigated since the 1960s, in order to assist the transfer of drugs across the paracellular space in the intestinal epithelium. However, few absorption enhancers are presently used clinically, due to the difficulty of developing enhancers with high specificity and low toxicity. Using high-throughput genomic techniques, new drug candidates such as, non-Lipinski molecules, peptides, antibodies and nucleic acids, are being discovered, so the need for oral drug delivery strategies using absorption enhancers is gaining importance. The key to addressing this issue is to understand the molecular mechanism of the paracellular route in epithelial cell sheets. Towards this end, basic research in cell biology has revealed the components that regulate the paracellular route, and how the transport of substances is regulated. Based on these findings, novel strategies for enhancing drug absorption have been proposed. In this article, the authors first survey the development of absorption enhancers, then outline recent progress in the cell biology of tight junctions, and finally discuss novel approaches for absorption enhancers based on these advances.
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Affiliation(s)
- Masuo Kondoh
- Osaka University, Department of Bio-Functional Molecular Chemistry, Graduate School of Pharmaceutical Sciences, Suita, Osaka 565-0871, Japan.
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