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Schaffenrath J, Keller A. New Insights in the Complexity and Functionality of the Neurovascular Unit. Handb Exp Pharmacol 2020; 273:33-57. [PMID: 33582883 DOI: 10.1007/164_2020_424] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The neurovascular unit (NVU) encompasses all brain cells and underlines that neurons, glia and brain vasculature are in intimate physical and functional association. Brain function is dependent on blood flow and local increases in blood flow in response to neural activity - functional hyperaemia takes place at the NVU. Although this is a vital function of the NVU, many studies have demonstrated that the NVU also performs other tasks. Blood vessels in the brain, which are composed of multiple cell types, are essential for correct brain development. They constitute the niche for brain stem cells, sense the environment and communicate changes to neural tissue, and control the immune quiescence of the CNS. In this brief chapter we will discuss new insights into the biology of NVU, which have further revealed the heterogeneity and complexity of the vascular tree and its neurovascular associations.
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Affiliation(s)
- Johanna Schaffenrath
- Department of Neurosurgery, Clinical Neuroscience Center, Zurich Neuroscience Center, Zurich University Hospital, Zurich University, Zurich, Switzerland
| | - Annika Keller
- Department of Neurosurgery, Clinical Neuroscience Center, Zurich Neuroscience Center, Zurich University Hospital, Zurich University, Zurich, Switzerland.
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52
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Hesh CA, Qiu Y, Lam WA. Vascularized Microfluidics and the Blood-Endothelium Interface. MICROMACHINES 2019; 11:E18. [PMID: 31878018 PMCID: PMC7019435 DOI: 10.3390/mi11010018] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 12/19/2019] [Accepted: 12/20/2019] [Indexed: 12/13/2022]
Abstract
The microvasculature is the primary conduit through which the human body transmits oxygen, nutrients, and other biological information to its peripheral tissues. It does this through bidirectional communication between the blood, consisting of plasma and non-adherent cells, and the microvascular endothelium. Current understanding of this blood-endothelium interface has been predominantly derived from a combination of reductionist two-dimensional in vitro models and biologically complex in vivo animal models, both of which recapitulate the human microvasculature to varying but limited degrees. In an effort to address these limitations, vascularized microfluidics have become a platform of increasing importance as a consequence of their ability to isolate biologically complex phenomena while also recapitulating biochemical and biophysical behaviors known to be important to the function of the blood-endothelium interface. In this review, we discuss the basic principles of vascularized microfluidic fabrication, the contribution this platform has made to our understanding of the blood-endothelium interface in both homeostasis and disease, the limitations and challenges of these vascularized microfluidics for studying this interface, and how these inform future directions.
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Affiliation(s)
- Christopher A. Hesh
- Department of Radiology & Imaging Sciences, Emory University School of Medicine, Atlanta, GA 30322, USA;
| | - Yongzhi Qiu
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA 30322, USA
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, Aflac Cancer Center and Blood Disorders Service of Children’s Healthcare of Atlanta, Emory University School of Medicine, Atlanta, GA 30322, USA
- Winship Cancer Institute of Emory University, Atlanta, GA 30322, USA
- Parker H. Petit Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA 30322, USA
| | - Wilbur A. Lam
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA 30322, USA
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, Aflac Cancer Center and Blood Disorders Service of Children’s Healthcare of Atlanta, Emory University School of Medicine, Atlanta, GA 30322, USA
- Winship Cancer Institute of Emory University, Atlanta, GA 30322, USA
- Parker H. Petit Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA 30322, USA
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53
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Adhesion G protein-coupled receptors: opportunities for drug discovery. Nat Rev Drug Discov 2019; 18:869-884. [PMID: 31462748 DOI: 10.1038/s41573-019-0039-y] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/18/2019] [Indexed: 12/24/2022]
Abstract
Adhesion G protein-coupled receptors (aGPCRs) - one of the five main families in the GPCR superfamily - have several atypical characteristics, including large, multi-domain N termini and a highly conserved region that can be autoproteolytically cleaved. Although GPCRs overall have well-established pharmacological tractability, currently no therapies that target any of the 33 members of the aGPCR family are either approved or in clinical trials. However, human genetics and preclinical research have strengthened the links between aGPCRs and disease in recent years. This, together with a greater understanding of their functional complexity, has led to growing interest in aGPCRs as drug targets. A framework for prioritizing aGPCR targets and supporting approaches to develop aGPCR modulators could therefore be valuable in harnessing the untapped therapeutic potential of this family. With this in mind, here we discuss the unique opportunities and challenges for drug discovery in modulating aGPCR functions, including target identification, target validation, assay development and safety considerations, using ADGRG1 as an illustrative example.
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54
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Chen DY, Sun NH, Lu YP, Hong LJ, Cui TT, Wang CK, Chen XH, Wang SS, Feng LL, Shi WX, Fukunaga K, Chen Z, Lu YM, Han F. GPR124 facilitates pericyte polarization and migration by regulating the formation of filopodia during ischemic injury. Theranostics 2019; 9:5937-5955. [PMID: 31534530 PMCID: PMC6735362 DOI: 10.7150/thno.34168] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Accepted: 07/28/2019] [Indexed: 12/31/2022] Open
Abstract
Prolonged occlusion of multiple microvessels causes microvascular injury. G protein-coupled receptor 124 (GPR124) has been reported to be required for maintaining central nervous system (CNS) angiogenesis and blood-brain barrier integrity. However, the molecular mechanisms by which GPR124 regulates pericytes during ischemia have remained elusive. Methods: A microsphere embolism-induced ischemia model was used to evaluate the expression of GPR124 following microsphere embolism. Immunocytochemistry and stochastic optical reconstruction microscopy imaging were used to assess the expression and distribution of GPR124 in human brain vascular pericytes (HBVPs) and after the treatment with 3-morpholino-sydnonimine (SIN-1) or oxygen-glucose deprivation (OGD). The effect of GPR124 knockdown or overexpression on HBVP migration was analyzed in vitro using wound healing assays and a microfluidic device. GPR124 loss-of-function studies were performed in HBVPs and HEK293 cells using CRISPR-Cas9-mediated gene deletion. Time-lapse imaging was used to assess dynamic changes in the formation of filopodia in an individual cell. Finally, to explore the functional domains required for GPR124 activity, deletion mutants were constructed for each of the N-terminal domains. Results: GPR124 expression was increased in pericytes following microsphere embolism. Morphological analysis showed localization of GPR124 to focal adhesions where GPR124 bound directly to the actin binding protein vinculin and upregulated Cdc42. SIN-1 or OGD treatment redistributed GPR124 to the leading edges of HBVPs where GPR124 signaling was required for pericyte filopodia formation and directional migration. Partial deletion of GPR124 domains decreased SIN-1-induced filopodia formation and cell migration. Conclusion: Taken together, our results provide the first evidence for a role of GPR124 in pericyte migration under ischemic conditions and suggest that GPR124 was essential for Cdc42 activation and filopodia formation.
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55
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Li H, Miki T, Almeida GMD, Hanashima C, Matsuzaki T, Kuo CJ, Watanabe N, Noda M. RECK in Neural Precursor Cells Plays a Critical Role in Mouse Forebrain Angiogenesis. iScience 2019; 19:559-571. [PMID: 31445376 PMCID: PMC6713797 DOI: 10.1016/j.isci.2019.08.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 05/28/2019] [Accepted: 08/05/2019] [Indexed: 01/10/2023] Open
Abstract
RECK in neural precursor cells (NPCs) was previously found to support Notch-dependent neurogenesis in mice. On the other hand, recent studies implicate RECK in endothelial cells (ECs) in WNT7-triggered canonical WNT signaling essential for brain angiogenesis. Here we report that RECK in NPCs is also critical for brain angiogenesis. When Reck is inactivated in Foxg1-positive NPCs, mice die shortly after birth with hemorrhage in the forebrain, with angiogenic sprouts stalling at the periphery and forming abnormal aggregates reminiscent of those in EC-selective Reck knockout mice and Wnt7a/b-deficient mice. The hemorrhage can be pharmacologically suppressed by lithium chloride. An effect of RECK in WNT7-producing cells to enhance canonical WNT-signaling in reporter cells is detectable in mixed culture but not with conditioned medium. Our findings suggest that NPC-expressed RECK has a non-cell-autonomous function to promote forebrain angiogenesis through contact-dependent enhancement of WNT signaling in ECs, implying possible involvement of RECK in neurovascular coupling. Mice lacking RECK in Foxg1-positive neural precursor cells die shortly after birth These mice show vascular defects similar to those in mice lacking endothelial RECK The vascular phenotype can be suppressed by LiCl, an activator of WNT signaling RECK in WNT7-producing cell enhances contact-dependent WNT signaling in adjacent cells
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Affiliation(s)
- Huiping Li
- Department of Molecular Oncology, Kyoto University Graduate School of Medicine, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan; Laboratory of Single-Molecule Cell Biology, Kyoto University Graduate School of Biostudies, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Takao Miki
- Department of Molecular Oncology, Kyoto University Graduate School of Medicine, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Glícia Maria de Almeida
- Department of Molecular Oncology, Kyoto University Graduate School of Medicine, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Carina Hanashima
- Department of Biology, Faculty of Education and Integrated Arts and Sciences, Waseda University, Shinjuku-ku, Tokyo 162-8480, Japan
| | - Tomoko Matsuzaki
- Department of Molecular Oncology, Kyoto University Graduate School of Medicine, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Calvin J Kuo
- Stanford University School of Medicine, Department of Medicine, Division of Hematology, Lokey Stem Cell Research Building, 265 Campus Drive, Stanford, CA 94305, USA
| | - Naoki Watanabe
- Laboratory of Single-Molecule Cell Biology, Kyoto University Graduate School of Biostudies, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan; Department of Pharmacology, Kyoto University Graduate School of Medicine, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Makoto Noda
- Department of Molecular Oncology, Kyoto University Graduate School of Medicine, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan.
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56
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Zhang C, Lai MB, Pedler MG, Johnson V, Adams RH, Petrash JM, Chen Z, Junge HJ. Endothelial Cell-Specific Inactivation of TSPAN12 (Tetraspanin 12) Reveals Pathological Consequences of Barrier Defects in an Otherwise Intact Vasculature. Arterioscler Thromb Vasc Biol 2019; 38:2691-2705. [PMID: 30354230 PMCID: PMC6221394 DOI: 10.1161/atvbaha.118.311689] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Supplemental Digital Content is available in the text. Objective— Blood-CNS (central nervous system) barrier defects are implicated in retinopathies, neurodegenerative diseases, stroke, and epilepsy, yet, the pathological mechanisms downstream of barrier defects remain incompletely understood. Blood-retina barrier (BRB) formation and retinal angiogenesis require β-catenin signaling induced by the ligand norrin (NDP [Norrie disease protein]), the receptor FZD4 (frizzled 4), coreceptor LRP5 (low-density lipoprotein receptor-like protein 5), and the tetraspanin TSPAN12 (tetraspanin 12). Impaired NDP/FZD4 signaling causes familial exudative vitreoretinopathy, which may lead to blindness. This study seeked to define cell type-specific functions of TSPAN12 in the retina. Approach and Results— A loxP-flanked Tspan12 allele was generated and recombined in endothelial cells using a tamoxifen-inducible Cdh5-CreERT2 driver. Resulting phenotypes were documented using confocal microscopy. RNA-Seq, histopathologic analysis, and electroretinogram were performed on retinas of aged mice. We show that TSPAN12 functions in endothelial cells to promote vascular morphogenesis and BRB formation in developing mice and BRB maintenance in adult mice. Early loss of TSPAN12 in endothelial cells causes lack of intraretinal capillaries and increased VE-cadherin (CDH5 [cadherin5 aka VE-cadherin]) expression, consistent with premature vascular quiescence. Late loss of TSPAN12 strongly impairs BRB maintenance without affecting vascular morphogenesis, pericyte coverage, or perfusion. Long-term BRB defects are associated with immunoglobulin extravasation, complement deposition, cystoid edema, and impaired b-wave in electroretinograms. RNA-sequencing reveals transcriptional responses to the perturbation of the BRB, including genes involved in vascular basement membrane alterations in diabetic retinopathy. Conclusions— This study establishes mice with late endothelial cell–specific loss of Tspan12 as a model to study pathological consequences of BRB impairment in an otherwise intact vasculature.
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Affiliation(s)
- Chi Zhang
- From the Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder (C.Z., M.B.L., V.J., Z.C., H.J.J.)
| | - Maria B Lai
- From the Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder (C.Z., M.B.L., V.J., Z.C., H.J.J.)
| | - Michelle G Pedler
- Department of Ophthalmology, University of Colorado School of Medicine, Aurora (M.G.P., J.M.P.)
| | - Verity Johnson
- From the Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder (C.Z., M.B.L., V.J., Z.C., H.J.J.)
| | - Ralf H Adams
- Department of Tissue Morphogenesis, Max Planck Institute for Molecular Biomedicine, Faculty of Medicine, University of Münster, Germany (R.H.A.)
| | - J Mark Petrash
- Department of Ophthalmology, University of Colorado School of Medicine, Aurora (M.G.P., J.M.P.)
| | - Zhe Chen
- From the Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder (C.Z., M.B.L., V.J., Z.C., H.J.J.)
| | - Harald J Junge
- From the Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder (C.Z., M.B.L., V.J., Z.C., H.J.J.)
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57
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Cherry AE, Vicente JJ, Xu C, Morrison RS, Ong SE, Wordeman L, Stella N. GPR124 regulates microtubule assembly, mitotic progression, and glioblastoma cell proliferation. Glia 2019; 67:1558-1570. [PMID: 31058365 PMCID: PMC6557680 DOI: 10.1002/glia.23628] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Revised: 03/25/2019] [Accepted: 04/05/2019] [Indexed: 01/26/2023]
Abstract
GPR124 is involved in embryonic development and remains expressed by select organs. The importance of GPR124 during development suggests that its aberrant expression might participate in tumor growth. Here we show that both increases and decreases in GPR124 expression in glioblastoma cells reduce cell proliferation by differentially altering the duration mitotic progression. Using mass spectrometry-based proteomics, we discovered that GPR124 interacts with ch-TOG, a known regulator of both microtubule (MT)-plus-end assembly and mitotic progression. Accordingly, changes in GPR124 expression and ch-TOG similarly affect MT assembly measured by real-time microscopy in cells. Our study describes a novel molecular interaction involving GPR124 and ch-TOG at the plasma membrane that controls glioblastoma cell proliferation by modifying MT assembly rates and controlling the progression of distinct phases of mitosis.
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Affiliation(s)
- Allison E. Cherry
- Department of Pharmacology, University of Washington, Seattle, Washington
| | - Juan Jesus Vicente
- Department of Physiology and Biophysics, University of Washington, Seattle, Washington
| | - Cong Xu
- Department of Pharmacology, University of Washington, Seattle, Washington
| | | | - Shao-En Ong
- Department of Pharmacology, University of Washington, Seattle, Washington
| | - Linda Wordeman
- Department of Physiology and Biophysics, University of Washington, Seattle, Washington
| | - Nephi Stella
- Department of Pharmacology, University of Washington, Seattle, Washington
- Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, Washington
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58
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Abstract
The vertebrate vasculature displays high organotypic specialization, with the structure and function of blood vessels catering to the specific needs of each tissue. A unique feature of the central nervous system (CNS) vasculature is the blood-brain barrier (BBB). The BBB regulates substance influx and efflux to maintain a homeostatic environment for proper brain function. Here, we review the development and cell biology of the BBB, focusing on the cellular and molecular regulation of barrier formation and the maintenance of the BBB through adulthood. We summarize unique features of CNS endothelial cells and highlight recent progress in and general principles of barrier regulation. Finally, we illustrate why a mechanistic understanding of the development and maintenance of the BBB could provide novel therapeutic opportunities for CNS drug delivery.
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Affiliation(s)
- Urs H Langen
- Department of Neurobiology, Harvard Medical School, Boston, Massachusetts 02115, USA;
| | - Swathi Ayloo
- Department of Neurobiology, Harvard Medical School, Boston, Massachusetts 02115, USA;
| | - Chenghua Gu
- Department of Neurobiology, Harvard Medical School, Boston, Massachusetts 02115, USA;
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59
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Cho C, Wang Y, Smallwood PM, Williams J, Nathans J. Molecular determinants in Frizzled, Reck, and Wnt7a for ligand-specific signaling in neurovascular development. eLife 2019; 8:47300. [PMID: 31225798 PMCID: PMC6588345 DOI: 10.7554/elife.47300] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 06/07/2019] [Indexed: 12/28/2022] Open
Abstract
The molecular basis of Wnt-Frizzled specificity is a central question in developmental biology. Reck, a multi-domain and multi-functional glycosylphosphatidylinositol-anchored protein, specifically enhances beta-catenin signaling by Wnt7a and Wnt7b in cooperation with the 7-transmembrane protein Gpr124. Among amino acids that distinguish Wnt7a and Wnt7b from other Wnts, two clusters are essential for signaling in a Reck- and Gpr124-dependent manner. Both clusters are far from the site of Frizzled binding: one resides at the amino terminus and the second resides in a protruding loop. Within Reck, the fourth of five tandem repeats of an unusual domain with six-cysteines (the CC domain) is essential for Wnt7a stimulation: substitutions P256A and W261A in CC4 eliminate this activity without changing protein abundance or surface localization. Mouse embryos carrying ReckP256A,W261A have severe defects in forebrain angiogenesis, providing the strongest evidence to date that Reck promotes CNS angiogenesis by specifically stimulating Wnt7a and Wnt7b signaling.
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Affiliation(s)
- Chris Cho
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Yanshu Wang
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, United States.,Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Philip M Smallwood
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, United States.,Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, United States
| | - John Williams
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, United States.,Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Jeremy Nathans
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, United States.,Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, United States.,Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, United States.,Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, United States
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60
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Jensen LD, Hot B, Ramsköld D, Germano RFV, Yokota C, Giatrellis S, Lauschke VM, Hubmacher D, Li MX, Hupe M, Arnold TD, Sandberg R, Frisén J, Trusohamn M, Martowicz A, Wisniewska-Kruk J, Nyqvist D, Adams RH, Apte SS, Vanhollebeke B, Stenman JM, Kele J. Disruption of the Extracellular Matrix Progressively Impairs Central Nervous System Vascular Maturation Downstream of β-Catenin Signaling. Arterioscler Thromb Vasc Biol 2019; 39:1432-1447. [PMID: 31242033 PMCID: PMC6597191 DOI: 10.1161/atvbaha.119.312388] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Supplemental Digital Content is available in the text. Objective— The Wnt/β-catenin pathway orchestrates development of the blood-brain barrier, but the downstream mechanisms involved at different developmental windows and in different central nervous system (CNS) tissues have remained elusive. Approach and Results— Here, we create a new mouse model allowing spatiotemporal investigations of Wnt/β-catenin signaling by induced overexpression of Axin1, an inhibitor of β-catenin signaling, specifically in endothelial cells (Axin1iEC−OE). AOE (Axin1 overexpression) in Axin1iEC−OE mice at stages following the initial vascular invasion of the CNS did not impair angiogenesis but led to premature vascular regression followed by progressive dilation and inhibition of vascular maturation resulting in forebrain-specific hemorrhage 4 days post-AOE. Analysis of the temporal Wnt/β-catenin driven CNS vascular development in zebrafish also suggested that Axin1iEC−OE led to CNS vascular regression and impaired maturation but not inhibition of ongoing angiogenesis within the CNS. Transcriptomic profiling of isolated, β-catenin signaling-deficient endothelial cells during early blood-brain barrier–development (E11.5) revealed ECM (extracellular matrix) proteins as one of the most severely deregulated clusters. Among the 20 genes constituting the forebrain endothelial cell-specific response signature, 8 (Adamtsl2, Apod, Ctsw, Htra3, Pglyrp1, Spock2, Ttyh2, and Wfdc1) encoded bona fide ECM proteins. This specific β-catenin-responsive ECM signature was also repressed in Axin1iEC−OE and endothelial cell-specific β-catenin–knockout mice (Ctnnb1-KOiEC) during initial blood-brain barrier maturation (E14.5), consistent with an important role of Wnt/β-catenin signaling in orchestrating the development of the forebrain vascular ECM. Conclusions— These results suggest a novel mechanism of establishing a CNS endothelium-specific ECM signature downstream of Wnt-β-catenin that impact spatiotemporally on blood-brain barrier differentiation during forebrain vessel development.
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Affiliation(s)
- Lasse D Jensen
- From the Department of Medical and Health Sciences, Linköpings Universitet, Linköping, Sweden (L.D.J.)
| | - Belma Hot
- Department of Physiology and Pharmacology (B.H., V.M.L., J.K.), Karolinska Institutet, Stockholm, Sweden.,Ludwig Institute for Cancer Research Ltd, Stockholm, Sweden (B.H., D.R., C.Y., M.X.L., M.H., R.S., J.M.S., J.K.)
| | - Daniel Ramsköld
- Department of Medicine, Solna (D.R.), Karolinska Institutet, Stockholm, Sweden.,Department of Cell and Molecular Biology (D.R., S.G., R.S., J.F.), Karolinska Institutet, Stockholm, Sweden.,Ludwig Institute for Cancer Research Ltd, Stockholm, Sweden (B.H., D.R., C.Y., M.X.L., M.H., R.S., J.M.S., J.K.)
| | - Raoul F V Germano
- Laboratory of Neurovascular Signaling, Department of Molecular Biology, Université libre de Bruxelles, Belgium (R.F.V.G., B.V.)
| | - Chika Yokota
- Ludwig Institute for Cancer Research Ltd, Stockholm, Sweden (B.H., D.R., C.Y., M.X.L., M.H., R.S., J.M.S., J.K.).,Department of Biochemistry and Biophysics, Stockholm University, Sweden (C.Y.)
| | - Sarantis Giatrellis
- Department of Cell and Molecular Biology (D.R., S.G., R.S., J.F.), Karolinska Institutet, Stockholm, Sweden
| | - Volker M Lauschke
- Department of Physiology and Pharmacology (B.H., V.M.L., J.K.), Karolinska Institutet, Stockholm, Sweden
| | - Dirk Hubmacher
- Orthopaedic Research Laboratories, Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, NY (D.H.)
| | - Minerva X Li
- Ludwig Institute for Cancer Research Ltd, Stockholm, Sweden (B.H., D.R., C.Y., M.X.L., M.H., R.S., J.M.S., J.K.).,Department of Clinical Sciences, Lunds Universitet, Sweden (M.X.L.)
| | - Mike Hupe
- Ludwig Institute for Cancer Research Ltd, Stockholm, Sweden (B.H., D.R., C.Y., M.X.L., M.H., R.S., J.M.S., J.K.).,Developmental Biochemistry, Theodor Boveri Institute (Biocenter), University of Wuerzburg, Germany (M.H.)
| | - Thomas D Arnold
- Department of Pediatrics, University of California, San Francisco (T.D.A.)
| | - Rickard Sandberg
- Department of Cell and Molecular Biology (D.R., S.G., R.S., J.F.), Karolinska Institutet, Stockholm, Sweden.,Ludwig Institute for Cancer Research Ltd, Stockholm, Sweden (B.H., D.R., C.Y., M.X.L., M.H., R.S., J.M.S., J.K.)
| | - Jonas Frisén
- Department of Cell and Molecular Biology (D.R., S.G., R.S., J.F.), Karolinska Institutet, Stockholm, Sweden
| | - Marta Trusohamn
- Department of Medical Biochemistry and Biophysics (M.T., A.M., J.W.-K., D.N.), Karolinska Institutet, Stockholm, Sweden
| | - Agnieszka Martowicz
- Department of Medical Biochemistry and Biophysics (M.T., A.M., J.W.-K., D.N.), Karolinska Institutet, Stockholm, Sweden
| | - Joanna Wisniewska-Kruk
- Department of Medical Biochemistry and Biophysics (M.T., A.M., J.W.-K., D.N.), Karolinska Institutet, Stockholm, Sweden
| | - Daniel Nyqvist
- Department of Medical Biochemistry and Biophysics (M.T., A.M., J.W.-K., D.N.), Karolinska Institutet, Stockholm, Sweden
| | - Ralf H Adams
- Department of Tissue Morphogenesis Max-Planck-Institute for Molecular Biomedicine, University of Münster, Faculty of Medicine, Germany (R.H.A.)
| | - Suneel S Apte
- Department of Biomedical Engineering, Cleveland Clinic Lerner Research Institute, Cleveland Clinic Foundation (S.S.A.)
| | - Benoit Vanhollebeke
- Laboratory of Neurovascular Signaling, Department of Molecular Biology, Université libre de Bruxelles, Belgium (R.F.V.G., B.V.).,Walloon Excellence in Life Sciences and Biotechnology (WELBIO), Belgium (B.V.)
| | - Jan M Stenman
- Ludwig Institute for Cancer Research Ltd, Stockholm, Sweden (B.H., D.R., C.Y., M.X.L., M.H., R.S., J.M.S., J.K.)
| | - Julianna Kele
- Department of Physiology and Pharmacology (B.H., V.M.L., J.K.), Karolinska Institutet, Stockholm, Sweden.,Ludwig Institute for Cancer Research Ltd, Stockholm, Sweden (B.H., D.R., C.Y., M.X.L., M.H., R.S., J.M.S., J.K.)
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61
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Cho C, Wang Y, Smallwood PM, Williams J, Nathans J. Dlg1 activates beta-catenin signaling to regulate retinal angiogenesis and the blood-retina and blood-brain barriers. eLife 2019; 8:45542. [PMID: 31066677 PMCID: PMC6506210 DOI: 10.7554/elife.45542] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 04/14/2019] [Indexed: 12/18/2022] Open
Abstract
Beta-catenin (i.e., canonical Wnt) signaling controls CNS angiogenesis and the blood-brain and blood-retina barriers. To explore the role of the Discs large/membrane-associated guanylate kinase (Dlg/MAGUK) family of scaffolding proteins in beta-catenin signaling, we studied vascular endothelial cell (EC)-specific knockout of Dlg1/SAP97. EC-specific loss of Dlg1 produces a retinal vascular phenotype that closely matches the phenotype associated with reduced beta-catenin signaling, synergizes with genetically-directed reductions in beta-catenin signaling components, and can be rescued by stabilizing beta-catenin in ECs. In reporter cells with CRISPR/Cas9-mediated inactivation of Dlg1, transfection of Dlg1 enhances beta-catenin signaling ~4 fold. Surprisingly, Frizzled4, which contains a C-terminal PDZ-binding motif that can bind to Dlg1 PDZ domains, appears to function independently of Dlg1 in vivo. These data expand the repertoire of Dlg/MAGUK family functions to include a role in beta-catenin signaling, and they suggest that proteins other than Frizzled receptors interact with Dlg1 to enhance beta-catenin signaling.
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Affiliation(s)
- Chris Cho
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Yanshu Wang
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, United States.,Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Philip M Smallwood
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, United States.,Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, United States
| | - John Williams
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, United States.,Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Jeremy Nathans
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, United States.,Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, United States.,Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, United States.,Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, United States
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62
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Benz F, Wichitnaowarat V, Lehmann M, Germano RF, Mihova D, Macas J, Adams RH, Taketo MM, Plate KH, Guérit S, Vanhollebeke B, Liebner S. Low wnt/β-catenin signaling determines leaky vessels in the subfornical organ and affects water homeostasis in mice. eLife 2019; 8:43818. [PMID: 30932814 PMCID: PMC6481993 DOI: 10.7554/elife.43818] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Accepted: 03/28/2019] [Indexed: 12/17/2022] Open
Abstract
The circumventricular organs (CVOs) in the central nervous system (CNS) lack a vascular blood-brain barrier (BBB), creating communication sites for sensory or secretory neurons, involved in body homeostasis. Wnt/β-catenin signaling is essential for BBB development and maintenance in endothelial cells (ECs) in most CNS vessels. Here we show that in mouse development, as well as in adult mouse and zebrafish, CVO ECs rendered Wnt-reporter negative, suggesting low level pathway activity. Characterization of the subfornical organ (SFO) vasculature revealed heterogenous claudin-5 (Cldn5) and Plvap/Meca32 expression indicative for tight and leaky vessels, respectively. Dominant, EC-specific β-catenin transcription in mice, converted phenotypically leaky into BBB-like vessels, by augmenting Cldn5+vessels, stabilizing junctions and by reducing Plvap/Meca32+ and fenestrated vessels, resulting in decreased tracer permeability. Endothelial tightening augmented neuronal activity in the SFO of water restricted mice. Hence, regulating the SFO vessel barrier may influence neuronal function in the context of water homeostasis. Infections and diseases in the brain and spine can be very damaging and debilitating. Indeed, the central nervous system also needs a carefully controlled biochemical environment to survive. As such, all animals with a backbone have barriers and defenses to protect and preserve this key system. One of these is the blood-brain barrier, a physical barrier between the brain and the outside world. Where most blood vessels allow relatively free exchange of chemicals between the blood and surrounding cells, the blood-brain barrier controls what can move between the bloodstream and the brain. Yet, there are gaps in the blood-brain barrier, specifically within structures in the brain called the circumventricular organs. These leaky vessels allow the brain cells in these regions to monitor the blood and respond to changes, for example, by triggering sensations such as hunger, thirst or nausea. It is not clear what stops the blood-brain barrier from forming in these regions and what effect the presence of a barrier would have on the brains activity, or the health and behavior of the animal. Benz et al. have now used mice and zebrafish to examine the development and structure of the blood-brain barrier. The investigation revealed that the signals that induce the blood-brain barrier throughout the brain are absent in the circumventricular organs of both species. Next, by artificially activating a protein involved in cell-cell interactions in mice, Benz et al. created blood-brain barrier-like structures in circumventricular organs by converting the leaky vessels into tight ones. This change meant that the brain cells in these regions did not respond properly to water deprivation, which potentially may have affected the regulation of thirst in these mice. Understanding the blood-brain barrier could have a variety of impacts on how we treat diseases in the central nervous system. This includes stroke, brain tumors and Alzheimers disease. These findings could particularly help scientists to better understand conditions that affect basic needs like thirst and hunger.
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Affiliation(s)
- Fabienne Benz
- Institute of Neurology (Edinger Institute), University Hospital, Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Viraya Wichitnaowarat
- Institute of Neurology (Edinger Institute), University Hospital, Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Martin Lehmann
- Institute of Neurology (Edinger Institute), University Hospital, Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Raoul Fv Germano
- Laboratory of Neurovascular Signaling, Department of Molecular Biology, ULB Neuroscience Institute, Université libre de Bruxelles, Bruxelles, Belgium
| | - Diana Mihova
- Institute of Neurology (Edinger Institute), University Hospital, Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Jadranka Macas
- Institute of Neurology (Edinger Institute), University Hospital, Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Ralf H Adams
- Department of Tissue Morphogenesis, Max-Planck-Institute for Molecular Biomedicine, University of Münster, Faculty of Medicine, Münster, Germany
| | - M Mark Taketo
- Division of Experimental Therapeutics, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Karl-Heinz Plate
- Institute of Neurology (Edinger Institute), University Hospital, Goethe University Frankfurt, Frankfurt am Main, Germany.,Excellence Cluster Cardio-Pulmonary systems (ECCPS), Partner site Frankfurt, Frankfurt, Germany.,German Cancer Consortium (DKTK), Partner Site Frankfurt/Mainz, Frankfurt, Germany.,German Center for Cardiovascular Research (DZHK), Partner site Frankfurt/Mainz, Frankfurt, Germany.,German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Sylvaine Guérit
- Institute of Neurology (Edinger Institute), University Hospital, Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Benoit Vanhollebeke
- Laboratory of Neurovascular Signaling, Department of Molecular Biology, ULB Neuroscience Institute, Université libre de Bruxelles, Bruxelles, Belgium.,Walloon Excellence in Life Sciences and Biotechnology (WELBIO), Wallonia, Belgium
| | - Stefan Liebner
- Institute of Neurology (Edinger Institute), University Hospital, Goethe University Frankfurt, Frankfurt am Main, Germany.,Excellence Cluster Cardio-Pulmonary systems (ECCPS), Partner site Frankfurt, Frankfurt, Germany.,German Cancer Consortium (DKTK), Partner Site Frankfurt/Mainz, Frankfurt, Germany
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63
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Sweeney MD, Zhao Z, Montagne A, Nelson AR, Zlokovic BV. Blood-Brain Barrier: From Physiology to Disease and Back. Physiol Rev 2019; 99:21-78. [PMID: 30280653 PMCID: PMC6335099 DOI: 10.1152/physrev.00050.2017] [Citation(s) in RCA: 1125] [Impact Index Per Article: 225.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 04/17/2018] [Accepted: 04/17/2018] [Indexed: 12/12/2022] Open
Abstract
The blood-brain barrier (BBB) prevents neurotoxic plasma components, blood cells, and pathogens from entering the brain. At the same time, the BBB regulates transport of molecules into and out of the central nervous system (CNS), which maintains tightly controlled chemical composition of the neuronal milieu that is required for proper neuronal functioning. In this review, we first examine molecular and cellular mechanisms underlying the establishment of the BBB. Then, we focus on BBB transport physiology, endothelial and pericyte transporters, and perivascular and paravascular transport. Next, we discuss rare human monogenic neurological disorders with the primary genetic defect in BBB-associated cells demonstrating the link between BBB breakdown and neurodegeneration. Then, we review the effects of genes underlying inheritance and/or increased susceptibility for Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease, and amyotrophic lateral sclerosis (ALS) on BBB in relation to other pathologies and neurological deficits. We next examine how BBB dysfunction relates to neurological deficits and other pathologies in the majority of sporadic AD, PD, and ALS cases, multiple sclerosis, other neurodegenerative disorders, and acute CNS disorders such as stroke, traumatic brain injury, spinal cord injury, and epilepsy. Lastly, we discuss BBB-based therapeutic opportunities. We conclude with lessons learned and future directions, with emphasis on technological advances to investigate the BBB functions in the living human brain, and at the molecular and cellular level, and address key unanswered questions.
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Affiliation(s)
- Melanie D Sweeney
- Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California , Los Angeles, California ; and Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California , Los Angeles, California
| | - Zhen Zhao
- Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California , Los Angeles, California ; and Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California , Los Angeles, California
| | - Axel Montagne
- Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California , Los Angeles, California ; and Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California , Los Angeles, California
| | - Amy R Nelson
- Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California , Los Angeles, California ; and Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California , Los Angeles, California
| | - Berislav V Zlokovic
- Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California , Los Angeles, California ; and Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California , Los Angeles, California
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64
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Saunders NR, Dziegielewska KM, Møllgård K, Habgood MD. Physiology and molecular biology of barrier mechanisms in the fetal and neonatal brain. J Physiol 2018; 596:5723-5756. [PMID: 29774535 PMCID: PMC6265560 DOI: 10.1113/jp275376] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2018] [Accepted: 03/12/2018] [Indexed: 12/11/2022] Open
Abstract
Properties of the local internal environment of the adult brain are tightly controlled providing a stable milieu essential for its normal function. The mechanisms involved in this complex control are structural, molecular and physiological (influx and efflux transporters) frequently referred to as the 'blood-brain barrier'. These mechanisms include regulation of ion levels in brain interstitial fluid essential for normal neuronal function, supply of nutrients, removal of metabolic products, and prevention of entry or elimination of toxic agents. A key feature is cerebrospinal fluid secretion and turnover. This is much less during development, allowing greater accumulation of permeating molecules. The overall effect of these mechanisms is to tightly control the exchange of molecules into and out of the brain. This review presents experimental evidence currently available on the status of these mechanisms in developing brain. It has been frequently stated for over nearly a century that the blood-brain barrier is not present or at least is functionally deficient in the embryo, fetus and newborn. We suggest the alternative hypothesis that the barrier mechanisms in developing brain are likely to be appropriately matched to each stage of its development. The contributions of different barrier mechanisms, such as changes in constituents of cerebrospinal fluid in relation to specific features of brain development, for example neurogenesis, are only beginning to be studied. The evidence on this previously neglected aspect of brain barrier function is outlined. We also suggest future directions this field could follow with special emphasis on potential applications in a clinical setting.
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Affiliation(s)
- Norman R. Saunders
- Department of Pharmacology and TherapeuticsUniversity of MelbourneParkvilleVictoriaAustralia
- Department of Cellular and Molecular Medicine, Faculty of Health and Medical SciencesUniversity of CopenhagenBlegdamsvej 3CopenhagenDenmark
| | - Katarzyna M. Dziegielewska
- Department of Pharmacology and TherapeuticsUniversity of MelbourneParkvilleVictoriaAustralia
- Department of Cellular and Molecular Medicine, Faculty of Health and Medical SciencesUniversity of CopenhagenBlegdamsvej 3CopenhagenDenmark
| | - Kjeld Møllgård
- Department of Pharmacology and TherapeuticsUniversity of MelbourneParkvilleVictoriaAustralia
- Department of Cellular and Molecular Medicine, Faculty of Health and Medical SciencesUniversity of CopenhagenBlegdamsvej 3CopenhagenDenmark
| | - Mark D. Habgood
- Department of Pharmacology and TherapeuticsUniversity of MelbourneParkvilleVictoriaAustralia
- Department of Cellular and Molecular Medicine, Faculty of Health and Medical SciencesUniversity of CopenhagenBlegdamsvej 3CopenhagenDenmark
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65
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Chong ZS, Ohnishi S, Yusa K, Wright GJ. Pooled extracellular receptor-ligand interaction screening using CRISPR activation. Genome Biol 2018; 19:205. [PMID: 30477585 PMCID: PMC6258485 DOI: 10.1186/s13059-018-1581-3] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Accepted: 11/07/2018] [Indexed: 12/30/2022] Open
Abstract
Extracellular interactions between cell surface receptors are necessary for signaling and adhesion but identifying them remains technically challenging. We describe a cell-based genome-wide approach employing CRISPR activation to identify receptors for a defined ligand. We show receptors for high-affinity antibodies and low-affinity ligands can be unambiguously identified when used in pools or as individual binding probes. We apply this technique to identify ligands for the adhesion G-protein-coupled receptors and show that the Nogo myelin-associated inhibitory proteins are ligands for ADGRB1. This method will enable extracellular receptor-ligand identification on a genome-wide scale.
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Affiliation(s)
- Zheng-Shan Chong
- 0000 0004 0606 5382grid.10306.34Cell Surface Signalling Laboratory, Wellcome Sanger Institute, Cambridge, CB10 1SA UK
| | - Shuhei Ohnishi
- 0000 0004 0606 5382grid.10306.34Stem Cell Genetics Laboratory, Wellcome Sanger Institute, Cambridge, CB10 1SA UK
| | - Kosuke Yusa
- 0000 0004 0606 5382grid.10306.34Stem Cell Genetics Laboratory, Wellcome Sanger Institute, Cambridge, CB10 1SA UK
| | - Gavin J. Wright
- 0000 0004 0606 5382grid.10306.34Cell Surface Signalling Laboratory, Wellcome Sanger Institute, Cambridge, CB10 1SA UK
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66
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Interplay of the Norrin and Wnt7a/Wnt7b signaling systems in blood-brain barrier and blood-retina barrier development and maintenance. Proc Natl Acad Sci U S A 2018; 115:E11827-E11836. [PMID: 30478038 DOI: 10.1073/pnas.1813217115] [Citation(s) in RCA: 92] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
β-Catenin signaling controls the development and maintenance of the blood-brain barrier (BBB) and the blood-retina barrier (BRB), but the division of labor and degree of redundancy between the two principal ligand-receptor systems-the Norrin and Wnt7a/Wnt7b systems-are incompletely defined. Here, we present a loss-of-function genetic analysis of postnatal BBB and BRB maintenance in mice that shows striking threshold and partial redundancy effects. In particular, the combined loss of Wnt7a and Norrin or Wnt7a and Frizzled4 (Fz4) leads to anatomically localized BBB defects that are far more severe than observed with loss of Wnt7a, Norrin, or Fz4 alone. In the cerebellum, selective loss of Wnt7a in glia combined with ubiquitous loss of Norrin recapitulates the phenotype observed with ubiquitous loss of both Wnt7a and Norrin, implying that glia are the source of Wnt7a in the cerebellum. Tspan12, a coactivator of Norrin signaling in the retina, is also active in BBB maintenance but is less potent than Norrin, consistent with a model in which Tspan12 enhances the amplitude of the Norrin signal in vascular endothelial cells. Finally, in the context of a partially impaired Norrin system, the retina reveals a small contribution to BRB development from the Wnt7a/Wnt7b system. Taken together, these experiments define the extent of CNS region-specific cooperation for several components of the Norrin and Wnt7a/Wnt7b systems, and they reveal substantial regional heterogeneity in the extent to which partially redundant ligands, receptors, and coactivators maintain the BBB and BRB.
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67
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Sharif Y, Jumah F, Coplan L, Krosser A, Sharif K, Tubbs RS. Blood brain barrier: A review of its anatomy and physiology in health and disease. Clin Anat 2018; 31:812-823. [PMID: 29637627 DOI: 10.1002/ca.23083] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 04/03/2018] [Indexed: 12/14/2022]
Abstract
The blood-brain barrier (BBB) is the principal regulator of transport of molecules and cells into and out of the central nervous system (CNS). It comprises endothelial cells, pericytes, immune cells, astrocytes, and basement membrane, collectively known as the neurovascular unit. The development of the barrier involves many complex pathways from all the progenitors of the neurovascular unit, but the timing of its formation is not entirely known. The coordinated activities of all the components of the neurovascular unit and other tissues ensure that materials required for growth and maintenance are allowed into the CNS while extraneous ones are excluded. This review summarizes current knowledge of the anatomy, development, and physiology of the BBB, and alterations that occur in disease conditions. Clin. Anat. 31:812-823, 2018. © 2018 Wiley Periodicals, Inc.
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Affiliation(s)
- Yousra Sharif
- Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
| | - Fareed Jumah
- Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
| | - Louis Coplan
- Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
| | - Alec Krosser
- Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
| | - Kassem Sharif
- Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
| | - R Shane Tubbs
- Department of Anatomical Sciences, St. George's University, Grenada.,Seattle Science Foundation, Seattle, Washington
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68
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Castro PR, Barbosa AS, Pereira JM, Ranfley H, Felipetto M, Gonçalves CAX, Paiva IR, Berg BB, Barcelos LS. Cellular and Molecular Heterogeneity Associated with Vessel Formation Processes. BIOMED RESEARCH INTERNATIONAL 2018; 2018:6740408. [PMID: 30406137 PMCID: PMC6199857 DOI: 10.1155/2018/6740408] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/01/2018] [Accepted: 09/06/2018] [Indexed: 12/11/2022]
Abstract
The microvasculature heterogeneity is a complex subject in vascular biology. The difficulty of building a dynamic and interactive view among the microenvironments, the cellular and molecular heterogeneities, and the basic aspects of the vessel formation processes make the available knowledge largely fragmented. The neovascularisation processes, termed vasculogenesis, angiogenesis, arteriogenesis, and lymphangiogenesis, are important to the formation and proper functioning of organs and tissues both in the embryo and the postnatal period. These processes are intrinsically related to microvascular cells, such as endothelial and mural cells. These cells are able to adjust their activities in response to the metabolic and physiological requirements of the tissues, by displaying a broad plasticity that results in a significant cellular and molecular heterogeneity. In this review, we intend to approach the microvasculature heterogeneity in an integrated view considering the diversity of neovascularisation processes and the cellular and molecular heterogeneity that contribute to microcirculatory homeostasis. For that, we will cover their interactions in the different blood-organ barriers and discuss how they cooperate in an integrated regulatory network that is controlled by specific molecular signatures.
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Affiliation(s)
- Pollyana Ribeiro Castro
- Department of Physiology and Biophysics, Instituto de Ciências Biológicas (ICB), Universidade Federal de Minas Gerais (UFMG), Brazil
| | - Alan Sales Barbosa
- Department of Physiology and Biophysics, Instituto de Ciências Biológicas (ICB), Universidade Federal de Minas Gerais (UFMG), Brazil
| | - Jousie Michel Pereira
- Department of Physiology and Biophysics, Instituto de Ciências Biológicas (ICB), Universidade Federal de Minas Gerais (UFMG), Brazil
| | - Hedden Ranfley
- Department of Physiology and Biophysics, Instituto de Ciências Biológicas (ICB), Universidade Federal de Minas Gerais (UFMG), Brazil
| | - Mariane Felipetto
- Department of Physiology and Biophysics, Instituto de Ciências Biológicas (ICB), Universidade Federal de Minas Gerais (UFMG), Brazil
| | - Carlos Alberto Xavier Gonçalves
- Department of Biochemistry and Immunology, Instituto de Ciências Biológicas (ICB), Universidade Federal de Minas Gerais (UFMG), Brazil
| | - Isabela Ribeiro Paiva
- Department of Pharmacology, Instituto de Ciências Biológicas (ICB), Universidade Federal de Minas Gerais (UFMG), Brazil
| | - Bárbara Betônico Berg
- Department of Pharmacology, Instituto de Ciências Biológicas (ICB), Universidade Federal de Minas Gerais (UFMG), Brazil
| | - Luciola Silva Barcelos
- Department of Physiology and Biophysics, Instituto de Ciências Biológicas (ICB), Universidade Federal de Minas Gerais (UFMG), Brazil
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69
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Sabbagh MF, Heng JS, Luo C, Castanon RG, Nery JR, Rattner A, Goff LA, Ecker JR, Nathans J. Transcriptional and epigenomic landscapes of CNS and non-CNS vascular endothelial cells. eLife 2018; 7:36187. [PMID: 30188322 PMCID: PMC6126923 DOI: 10.7554/elife.36187] [Citation(s) in RCA: 151] [Impact Index Per Article: 25.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 08/21/2018] [Indexed: 02/06/2023] Open
Abstract
Vascular endothelial cell (EC) function depends on appropriate organ-specific molecular and cellular specializations. To explore genomic mechanisms that control this specialization, we have analyzed and compared the transcriptome, accessible chromatin, and DNA methylome landscapes from mouse brain, liver, lung, and kidney ECs. Analysis of transcription factor (TF) gene expression and TF motifs at candidate cis-regulatory elements reveals both shared and organ-specific EC regulatory networks. In the embryo, only those ECs that are adjacent to or within the central nervous system (CNS) exhibit canonical Wnt signaling, which correlates precisely with blood-brain barrier (BBB) differentiation and Zic3 expression. In the early postnatal brain, single-cell RNA-seq of purified ECs reveals (1) close relationships between veins and mitotic cells and between arteries and tip cells, (2) a division of capillary ECs into vein-like and artery-like classes, and (3) new endothelial subtype markers, including new validated tip cell markers.
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Affiliation(s)
- Mark F Sabbagh
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, United States.,Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Jacob S Heng
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, United States.,Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Chongyuan Luo
- Genomic Analysis Laboratory, The Salk Institute for Biological Studies, La Jolla, United States.,Howard Hughes Medical Institute, The Salk Institute for Biological Studies, La Jolla, United States
| | - Rosa G Castanon
- Genomic Analysis Laboratory, The Salk Institute for Biological Studies, La Jolla, United States
| | - Joseph R Nery
- Genomic Analysis Laboratory, The Salk Institute for Biological Studies, La Jolla, United States
| | - Amir Rattner
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Loyal A Goff
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, United States.,Institute for Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Joseph R Ecker
- Genomic Analysis Laboratory, The Salk Institute for Biological Studies, La Jolla, United States.,Howard Hughes Medical Institute, The Salk Institute for Biological Studies, La Jolla, United States
| | - Jeremy Nathans
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, United States.,Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, United States.,Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, United States.,Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, United States
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70
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Song S, Wang S, Pigott VM, Jiang T, Foley LM, Mishra A, Nayak R, Zhu W, Begum G, Shi Y, Carney KE, Hitchens TK, Shull GE, Sun D. Selective role of Na + /H + exchanger in Cx3cr1 + microglial activation, white matter demyelination, and post-stroke function recovery. Glia 2018; 66:2279-2298. [PMID: 30043461 DOI: 10.1002/glia.23456] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 03/27/2018] [Accepted: 04/24/2018] [Indexed: 12/22/2022]
Abstract
Na+ /H+ exchanger (NHE1) activation is required for multiple microglial functions. We investigated effects of selective deletion of microglial Nhe1 in Cx3cr1-CreER ;Nhe1f/f mice on neuroinflammation and tissue repair after ischemic stroke. Infarct volume was similar in corn oil or tamoxifen (Tam)-treated mice at 48 hr and 14 days post-stroke. However, the Tam-treated mice showed significantly higher survival rate and faster neurological function recovery during day 1-14 post-stroke. Deletion of microglial Nhe1 prevented the elevation of CD11b+ /CD45low-med microglia in the ischemic hemisphere at day 3 post-stroke, but stimulated expression of Ym1, CD68, TGF-β, IL-10, decreased expression of CD86 and IL-1β, and reduced GFAP+ reactive astrocytes. Moreover, at day 14 post-stroke, enhanced white matter myelination was detected in the microglial Nhe1 deleted mice. In comparison, neuronal Nhe1-null mice (the CamKII-Cre+/- ;Nhe1f/f mice) showed a significant reduction in both acute and subacute infarct volume, along with increased survival rate and moderate neurological function recovery. However, these neuronal Nhe1-null mice did not exhibit reduced activation of CD11b+ /CD45low-med microglia or CD11b+ /CD45hi macrophages in the ischemic brains, and they exhibited no reductions in white matter lesions. Taken together, this study demonstrated that deletion of microglial and neuronal Nhe1 had differential effects on ischemic brain damage. Microglial NHE1 is involved in pro-inflammatory responses during post-stroke brain tissue repair. In contrast, neuronal NHE1 activation is directly associated with the acute ischemic neuronal injury but not inflammation. Our study reveals that NHE1 protein is a potential therapeutic target critical for differential regulation of ischemic neuronal injury, demyelination and tissue repair.
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Affiliation(s)
- Shanshan Song
- Department of Neurology, University of Pittsburgh, Pittsburgh, Pennsylvania, 15213.,Pittsburgh Institute for Neurodegenerative Disorders, University of Pittsburgh, Pittsburgh, Pennsylvania, 15213
| | - Shaoxia Wang
- Department of Neurology, University of Pittsburgh, Pittsburgh, Pennsylvania, 15213.,Tianjin State Key Laboratory of Modern Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, 300193, China
| | - Victoria M Pigott
- Department of Neurology, University of Pittsburgh, Pittsburgh, Pennsylvania, 15213.,Pittsburgh Institute for Neurodegenerative Disorders, University of Pittsburgh, Pittsburgh, Pennsylvania, 15213
| | - Tong Jiang
- Department of Neurology, University of Pittsburgh, Pittsburgh, Pennsylvania, 15213.,Pittsburgh Institute for Neurodegenerative Disorders, University of Pittsburgh, Pittsburgh, Pennsylvania, 15213
| | - Lesley M Foley
- Animal Imaging Center, University of Pittsburgh, Pittsburgh, Pennsylvania, 15213
| | - Abhishek Mishra
- Department of Neurology, University of Pittsburgh, Pittsburgh, Pennsylvania, 15213
| | - Rachana Nayak
- Department of Neurology, University of Pittsburgh, Pittsburgh, Pennsylvania, 15213
| | - Wen Zhu
- Department of Neurology, University of Pittsburgh, Pittsburgh, Pennsylvania, 15213
| | - Gulnaz Begum
- Department of Neurology, University of Pittsburgh, Pittsburgh, Pennsylvania, 15213.,Pittsburgh Institute for Neurodegenerative Disorders, University of Pittsburgh, Pittsburgh, Pennsylvania, 15213
| | - Yejie Shi
- Department of Neurology, University of Pittsburgh, Pittsburgh, Pennsylvania, 15213
| | - Karen E Carney
- Department of Neurology, University of Pittsburgh, Pittsburgh, Pennsylvania, 15213
| | - T Kevin Hitchens
- Animal Imaging Center, University of Pittsburgh, Pittsburgh, Pennsylvania, 15213.,Department of Neurobiology, University of Pittsburgh, Pittsburgh, Pennsylvania, 15213
| | - Gary E Shull
- Department of Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati, Cincinnati, Ohio, 45267
| | - Dandan Sun
- Department of Neurology, University of Pittsburgh, Pittsburgh, Pennsylvania, 15213.,Pittsburgh Institute for Neurodegenerative Disorders, University of Pittsburgh, Pittsburgh, Pennsylvania, 15213.,Veterans Affairs Pittsburgh Health Care System, Geriatric Research, Educational and Clinical Center, Pittsburgh, Pennsylvania
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71
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Eubelen M, Bostaille N, Cabochette P, Gauquier A, Tebabi P, Dumitru AC, Koehler M, Gut P, Alsteens D, Stainier DYR, Garcia-Pino A, Vanhollebeke B. A molecular mechanism for Wnt ligand-specific signaling. Science 2018; 361:science.aat1178. [PMID: 30026314 DOI: 10.1126/science.aat1178] [Citation(s) in RCA: 145] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Accepted: 06/26/2018] [Indexed: 12/29/2022]
Abstract
Wnt signaling is key to many developmental, physiological, and disease processes in which cells seem able to discriminate between multiple Wnt ligands. This selective Wnt recognition or "decoding" capacity has remained enigmatic because Wnt/Frizzled interactions are largely incompatible with monospecific recognition. Gpr124 and Reck enable brain endothelial cells to selectively respond to Wnt7. We show that Reck binds with low micromolar affinity to the intrinsically disordered linker region of Wnt7. Availability of Reck-bound Wnt7 for Frizzled signaling relies on the interaction between Gpr124 and Dishevelled. Through polymerization, Dishevelled recruits Gpr124 and the associated Reck-bound Wnt7 into dynamic Wnt/Frizzled/Lrp5/6 signalosomes, resulting in increased local concentrations of Wnt7 available for Frizzled signaling. This work provides mechanistic insights into the Wnt decoding capacities of vertebrate cells and unravels structural determinants of the functional diversification of Wnt family members.
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Affiliation(s)
- Marie Eubelen
- Laboratory of Neurovascular Signaling, Department of Molecular Biology, ULB Neuroscience Institute, Université libre de Bruxelles (ULB), Gosselies B-6041, Belgium
| | - Naguissa Bostaille
- Laboratory of Neurovascular Signaling, Department of Molecular Biology, ULB Neuroscience Institute, Université libre de Bruxelles (ULB), Gosselies B-6041, Belgium
| | - Pauline Cabochette
- Laboratory of Neurovascular Signaling, Department of Molecular Biology, ULB Neuroscience Institute, Université libre de Bruxelles (ULB), Gosselies B-6041, Belgium
| | - Anne Gauquier
- Laboratory of Neurovascular Signaling, Department of Molecular Biology, ULB Neuroscience Institute, Université libre de Bruxelles (ULB), Gosselies B-6041, Belgium
| | - Patricia Tebabi
- Laboratory of Neurovascular Signaling, Department of Molecular Biology, ULB Neuroscience Institute, Université libre de Bruxelles (ULB), Gosselies B-6041, Belgium
| | - Andra C Dumitru
- NanoBiophysics Laboratory, Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, 1348 Louvain-la-Neuve, Belgium
| | - Melanie Koehler
- NanoBiophysics Laboratory, Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, 1348 Louvain-la-Neuve, Belgium
| | - Philipp Gut
- Laboratory of Neurovascular Signaling, Department of Molecular Biology, ULB Neuroscience Institute, Université libre de Bruxelles (ULB), Gosselies B-6041, Belgium
| | - David Alsteens
- NanoBiophysics Laboratory, Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, 1348 Louvain-la-Neuve, Belgium
| | - Didier Y R Stainier
- Department of Developmental Genetics, Max Planck Institute for Heart and Lung Research, 61231 Bad Nauheim, Germany
| | - Abel Garcia-Pino
- Laboratory of Cellular and Molecular Microbiology, Department of Molecular Biology, ULB, Gosselies B-6041, Belgium.,Walloon Excellence in Life Sciences and Biotechnology (WELBIO), Belgium
| | - Benoit Vanhollebeke
- Laboratory of Neurovascular Signaling, Department of Molecular Biology, ULB Neuroscience Institute, Université libre de Bruxelles (ULB), Gosselies B-6041, Belgium. .,Walloon Excellence in Life Sciences and Biotechnology (WELBIO), Belgium.,Center for Microscopy and Molecular Imaging (CMMI), ULB, Gosselies B-6041, Belgium
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72
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Paredes I, Himmels P, Ruiz de Almodóvar C. Neurovascular Communication during CNS Development. Dev Cell 2018; 45:10-32. [PMID: 29634931 DOI: 10.1016/j.devcel.2018.01.023] [Citation(s) in RCA: 140] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 11/22/2017] [Accepted: 01/08/2018] [Indexed: 12/11/2022]
Abstract
A precise communication between the nervous and the vascular systems is crucial for proper formation and function of the central nervous system (CNS). Interestingly, this communication does not only occur by neural cells regulating the growth and properties of the vasculature, but new studies show that blood vessels actively control different neurodevelopmental processes. Here, we review the current knowledge on how neurons in particular influence growing blood vessels during CNS development and on how vessels participate in shaping the neural compartment. We also review the identified molecular mechanisms of this bidirectional communication.
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Affiliation(s)
- Isidora Paredes
- Biochemistry Center, Heidelberg University, 69120 Heidelberg, Germany; Interdisciplinary Center for Neurosciences, Heidelberg University, 69120 Heidelberg, Germany
| | - Patricia Himmels
- Biochemistry Center, Heidelberg University, 69120 Heidelberg, Germany; Interdisciplinary Center for Neurosciences, Heidelberg University, 69120 Heidelberg, Germany
| | - Carmen Ruiz de Almodóvar
- Biochemistry Center, Heidelberg University, 69120 Heidelberg, Germany; Interdisciplinary Center for Neurosciences, Heidelberg University, 69120 Heidelberg, Germany.
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73
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Sonar SA, Lal G. Blood–brain barrier and its function during inflammation and autoimmunity. J Leukoc Biol 2018. [DOI: 10.1002/jlb.1ru1117-428r order by 8029-- #] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
Abstract
The blood–brain barrier (BBB) is an important physiologic barrier that separates CNS from soluble inflammatory mediators and effector immune cells from peripheral circulation. The optimum function of the BBB is necessary for the homeostasis, maintenance, and proper neuronal function. The clinical and experimental findings have shown that BBB dysfunction is an early hallmark of various neurologic disorders ranging from inflammatory autoimmune, neurodegenerative, and traumatic diseases to neuroinvasive infections. Significant progress has been made in the understanding of the regulation of BBB function under homeostatic and neuroinflammatory conditions. Several neurologic disease-modifying drugs have shown to improve the BBB function. However, they have a broad-acting immunomodulatory function and can increase the risk of life-threatening infections. The recent development of in vitro multicomponent 3-dimensional BBB models coupled with fluidics chamber as well as a cell-type specific reporter and knockout mice gave a new boost to our understanding of the dynamics of the BBB. In the review, we discuss the current understanding of BBB composition and recent findings that illustrate the critical regulatory elements of the BBB function under physiologic and inflammatory conditions, and also suggested the strategies to control BBB structure and function.
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74
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Sonar SA, Lal G. Blood–brain barrier and its function during inflammation and autoimmunity. J Leukoc Biol 2018. [DOI: 10.1002/jlb.1ru1117-428r order by 8029-- -] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
Abstract
The blood–brain barrier (BBB) is an important physiologic barrier that separates CNS from soluble inflammatory mediators and effector immune cells from peripheral circulation. The optimum function of the BBB is necessary for the homeostasis, maintenance, and proper neuronal function. The clinical and experimental findings have shown that BBB dysfunction is an early hallmark of various neurologic disorders ranging from inflammatory autoimmune, neurodegenerative, and traumatic diseases to neuroinvasive infections. Significant progress has been made in the understanding of the regulation of BBB function under homeostatic and neuroinflammatory conditions. Several neurologic disease-modifying drugs have shown to improve the BBB function. However, they have a broad-acting immunomodulatory function and can increase the risk of life-threatening infections. The recent development of in vitro multicomponent 3-dimensional BBB models coupled with fluidics chamber as well as a cell-type specific reporter and knockout mice gave a new boost to our understanding of the dynamics of the BBB. In the review, we discuss the current understanding of BBB composition and recent findings that illustrate the critical regulatory elements of the BBB function under physiologic and inflammatory conditions, and also suggested the strategies to control BBB structure and function.
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75
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Sonar SA, Lal G. Blood–brain barrier and its function during inflammation and autoimmunity. J Leukoc Biol 2018. [DOI: 10.1002/jlb.1ru1117-428r order by 1-- gadu] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
Abstract
The blood–brain barrier (BBB) is an important physiologic barrier that separates CNS from soluble inflammatory mediators and effector immune cells from peripheral circulation. The optimum function of the BBB is necessary for the homeostasis, maintenance, and proper neuronal function. The clinical and experimental findings have shown that BBB dysfunction is an early hallmark of various neurologic disorders ranging from inflammatory autoimmune, neurodegenerative, and traumatic diseases to neuroinvasive infections. Significant progress has been made in the understanding of the regulation of BBB function under homeostatic and neuroinflammatory conditions. Several neurologic disease-modifying drugs have shown to improve the BBB function. However, they have a broad-acting immunomodulatory function and can increase the risk of life-threatening infections. The recent development of in vitro multicomponent 3-dimensional BBB models coupled with fluidics chamber as well as a cell-type specific reporter and knockout mice gave a new boost to our understanding of the dynamics of the BBB. In the review, we discuss the current understanding of BBB composition and recent findings that illustrate the critical regulatory elements of the BBB function under physiologic and inflammatory conditions, and also suggested the strategies to control BBB structure and function.
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76
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Sonar SA, Lal G. Blood–brain barrier and its function during inflammation and autoimmunity. J Leukoc Biol 2018. [DOI: 10.1002/jlb.1ru1117-428r and 1880=1880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
Abstract
The blood–brain barrier (BBB) is an important physiologic barrier that separates CNS from soluble inflammatory mediators and effector immune cells from peripheral circulation. The optimum function of the BBB is necessary for the homeostasis, maintenance, and proper neuronal function. The clinical and experimental findings have shown that BBB dysfunction is an early hallmark of various neurologic disorders ranging from inflammatory autoimmune, neurodegenerative, and traumatic diseases to neuroinvasive infections. Significant progress has been made in the understanding of the regulation of BBB function under homeostatic and neuroinflammatory conditions. Several neurologic disease-modifying drugs have shown to improve the BBB function. However, they have a broad-acting immunomodulatory function and can increase the risk of life-threatening infections. The recent development of in vitro multicomponent 3-dimensional BBB models coupled with fluidics chamber as well as a cell-type specific reporter and knockout mice gave a new boost to our understanding of the dynamics of the BBB. In the review, we discuss the current understanding of BBB composition and recent findings that illustrate the critical regulatory elements of the BBB function under physiologic and inflammatory conditions, and also suggested the strategies to control BBB structure and function.
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77
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Sonar SA, Lal G. Blood–brain barrier and its function during inflammation and autoimmunity. J Leukoc Biol 2018. [DOI: 10.1002/jlb.1ru1117-428r order by 1-- -] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
Abstract
The blood–brain barrier (BBB) is an important physiologic barrier that separates CNS from soluble inflammatory mediators and effector immune cells from peripheral circulation. The optimum function of the BBB is necessary for the homeostasis, maintenance, and proper neuronal function. The clinical and experimental findings have shown that BBB dysfunction is an early hallmark of various neurologic disorders ranging from inflammatory autoimmune, neurodegenerative, and traumatic diseases to neuroinvasive infections. Significant progress has been made in the understanding of the regulation of BBB function under homeostatic and neuroinflammatory conditions. Several neurologic disease-modifying drugs have shown to improve the BBB function. However, they have a broad-acting immunomodulatory function and can increase the risk of life-threatening infections. The recent development of in vitro multicomponent 3-dimensional BBB models coupled with fluidics chamber as well as a cell-type specific reporter and knockout mice gave a new boost to our understanding of the dynamics of the BBB. In the review, we discuss the current understanding of BBB composition and recent findings that illustrate the critical regulatory elements of the BBB function under physiologic and inflammatory conditions, and also suggested the strategies to control BBB structure and function.
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78
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Sonar SA, Lal G. Blood–brain barrier and its function during inflammation and autoimmunity. J Leukoc Biol 2018. [DOI: 10.1002/jlb.1ru1117-428r order by 8029-- awyx] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
Abstract
The blood–brain barrier (BBB) is an important physiologic barrier that separates CNS from soluble inflammatory mediators and effector immune cells from peripheral circulation. The optimum function of the BBB is necessary for the homeostasis, maintenance, and proper neuronal function. The clinical and experimental findings have shown that BBB dysfunction is an early hallmark of various neurologic disorders ranging from inflammatory autoimmune, neurodegenerative, and traumatic diseases to neuroinvasive infections. Significant progress has been made in the understanding of the regulation of BBB function under homeostatic and neuroinflammatory conditions. Several neurologic disease-modifying drugs have shown to improve the BBB function. However, they have a broad-acting immunomodulatory function and can increase the risk of life-threatening infections. The recent development of in vitro multicomponent 3-dimensional BBB models coupled with fluidics chamber as well as a cell-type specific reporter and knockout mice gave a new boost to our understanding of the dynamics of the BBB. In the review, we discuss the current understanding of BBB composition and recent findings that illustrate the critical regulatory elements of the BBB function under physiologic and inflammatory conditions, and also suggested the strategies to control BBB structure and function.
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79
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Sonar SA, Lal G. Blood–brain barrier and its function during inflammation and autoimmunity. J Leukoc Biol 2018. [DOI: 10.1002/jlb.1ru1117-428r order by 1-- #] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
Abstract
The blood–brain barrier (BBB) is an important physiologic barrier that separates CNS from soluble inflammatory mediators and effector immune cells from peripheral circulation. The optimum function of the BBB is necessary for the homeostasis, maintenance, and proper neuronal function. The clinical and experimental findings have shown that BBB dysfunction is an early hallmark of various neurologic disorders ranging from inflammatory autoimmune, neurodegenerative, and traumatic diseases to neuroinvasive infections. Significant progress has been made in the understanding of the regulation of BBB function under homeostatic and neuroinflammatory conditions. Several neurologic disease-modifying drugs have shown to improve the BBB function. However, they have a broad-acting immunomodulatory function and can increase the risk of life-threatening infections. The recent development of in vitro multicomponent 3-dimensional BBB models coupled with fluidics chamber as well as a cell-type specific reporter and knockout mice gave a new boost to our understanding of the dynamics of the BBB. In the review, we discuss the current understanding of BBB composition and recent findings that illustrate the critical regulatory elements of the BBB function under physiologic and inflammatory conditions, and also suggested the strategies to control BBB structure and function.
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80
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Miller CA, Dahiya S, Li T, Fulton RS, Smyth MD, Dunn GP, Rubin JB, Mardis ER. Resistance-promoting effects of ependymoma treatment revealed through genomic analysis of multiple recurrences in a single patient. Cold Spring Harb Mol Case Stud 2018; 4:mcs.a002444. [PMID: 29440180 PMCID: PMC5880262 DOI: 10.1101/mcs.a002444] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 12/26/2017] [Indexed: 12/11/2022] Open
Abstract
As in other brain tumors, multiple recurrences after complete resection and irradiation of supratentorial ependymoma are common and frequently result in patient death. This standard-of-care treatment was established in the pregenomic era without the ability to evaluate the effect that mutagenic therapies may exert on tumor evolution and in promoting resistance, recurrence, and death. We seized a rare opportunity to characterize treatment effects and the evolution of a single patient's ependymoma across four recurrences after different therapies. A combination of high-depth whole-genome and exome-based DNA sequencing of germline and tumor specimens, RNA sequencing of tumor specimens, and advanced computational analyses were used. Treatment with radiation and chemotherapies resulted in a substantial increase in mutational burden and diversification of the tumor subclonal architecture without eradication of the founding clone. Notable somatic alterations included a MEN1 driver, several epigenetic modifiers, and therapy-induced mutations that impacted multiple other cancer-relevant pathways and altered the neoantigen landscape. These genomic data provided new mechanistic insights into the genesis of ependymoma and pathways of resistance. They also revealed that radiation and chemotherapy were significant forces in shaping the increased subclonal complexity of each tumor recurrence while also failing to eradicate the founding clone. This raises the question of whether standard-of-care treatments have similar consequences in other patients with ependymoma and other types of brain tumors. If so, the perspective obtained by real-time genomic characterization of a tumor may be essential for making effective patient-specific and adaptive clinical decisions.
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Affiliation(s)
- Christopher A Miller
- Department of Medicine, Division of Oncology, Washington University School of Medicine, St. Louis, Missouri 63110, USA.,McDonnell Genome Institute, Washington University School of Medicine, St. Louis, Missouri 63110, USA
| | - Sonika Dahiya
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri 63110, USA
| | - Tiandao Li
- McDonnell Genome Institute, Washington University School of Medicine, St. Louis, Missouri 63110, USA
| | - Robert S Fulton
- McDonnell Genome Institute, Washington University School of Medicine, St. Louis, Missouri 63110, USA
| | - Matthew D Smyth
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, Missouri 63110, USA
| | - Gavin P Dunn
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, Missouri 63110, USA
| | - Joshua B Rubin
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri 63110, USA
| | - Elaine R Mardis
- Institute for Genomic Medicine, Nationwide Children's Hospital, and The Ohio State University College of Medicine, Columbus, Ohio 43205, USA
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81
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Gastfriend BD, Palecek SP, Shusta EV. Modeling the blood-brain barrier: Beyond the endothelial cells. CURRENT OPINION IN BIOMEDICAL ENGINEERING 2018; 5:6-12. [PMID: 29915815 DOI: 10.1016/j.cobme.2017.11.002] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The blood-brain barrier (BBB) regulates the transport of ions, nutrients, and metabolites to help maintain proper brain function. This restrictive interface formed by brain microvascular endothelial cells excludes the majority of small and large molecule drugs from entering the brain, and blood-brain barrier dysfunction is a signature of many neurological diseases. Thus, in vitro models of the BBB based on brain endothelial cells have been developed to facilitate screening drugs for BBB permeability. However, while brain endothelial cells form the main interface, they work in concert with other brain-resident cells such as neural progenitor cells, pericytes, astrocytes, and neurons to form the neurovascular unit (NVU). Importantly, non-endothelial cells of the NVU play key roles in eliciting BBB phenotypes and in regulating the dynamic responses of the BBB to brain activity and disease. As a result, emerging in vitro BBB models have incorporated these NVU cell types in addition to endothelial cells. These multicellular BBB or NVU models have found increasing application not only in drug screening, but also in studying complex cellular and molecular mechanisms underlying BBB biology and disease.
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Affiliation(s)
- Benjamin D Gastfriend
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, 1415 Engineering Drive, Madison WI, 53706
| | - Sean P Palecek
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, 1415 Engineering Drive, Madison WI, 53706
| | - Eric V Shusta
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, 1415 Engineering Drive, Madison WI, 53706
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82
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Sonar SA, Lal G. Blood-brain barrier and its function during inflammation and autoimmunity. J Leukoc Biol 2018; 103:839-853. [PMID: 29431873 DOI: 10.1002/jlb.1ru1117-428r] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 01/09/2018] [Accepted: 01/09/2018] [Indexed: 12/16/2022] Open
Abstract
The blood-brain barrier (BBB) is an important physiologic barrier that separates CNS from soluble inflammatory mediators and effector immune cells from peripheral circulation. The optimum function of the BBB is necessary for the homeostasis, maintenance, and proper neuronal function. The clinical and experimental findings have shown that BBB dysfunction is an early hallmark of various neurologic disorders ranging from inflammatory autoimmune, neurodegenerative, and traumatic diseases to neuroinvasive infections. Significant progress has been made in the understanding of the regulation of BBB function under homeostatic and neuroinflammatory conditions. Several neurologic disease-modifying drugs have shown to improve the BBB function. However, they have a broad-acting immunomodulatory function and can increase the risk of life-threatening infections. The recent development of in vitro multicomponent 3-dimensional BBB models coupled with fluidics chamber as well as a cell-type specific reporter and knockout mice gave a new boost to our understanding of the dynamics of the BBB. In the review, we discuss the current understanding of BBB composition and recent findings that illustrate the critical regulatory elements of the BBB function under physiologic and inflammatory conditions, and also suggested the strategies to control BBB structure and function.
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83
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Cazorla-Vázquez S, Engel FB. Adhesion GPCRs in Kidney Development and Disease. Front Cell Dev Biol 2018; 6:9. [PMID: 29468160 PMCID: PMC5808184 DOI: 10.3389/fcell.2018.00009] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Accepted: 01/23/2018] [Indexed: 12/25/2022] Open
Abstract
Chronic kidney disease (CKD) represents the fastest growing pathology worldwide with a prevalence of >10% in many countries. In addition, kidney cancer represents 5% of all new diagnosed cancers. As currently no effective therapies exist to restore kidney function after CKD- as well as cancer-induced renal damage, it is important to elucidate new regulators of kidney development and disease as new therapeutic targets. G protein-coupled receptors (GPCRs) represent the most successful class of pharmaceutical targets. In recent years adhesion GPCRs (aGPCRs), the second largest GPCR family, gained significant attention as they are present on almost all mammalian cells, are associated to a plethora of diseases and regulate important cellular processes. aGPCRs regulate for example cell polarity, mitotic spindle orientation, cell migration, and cell aggregation; all processes that play important roles in kidney development and/or disease. Moreover, polycystin-1, a major regulator of kidney development and disease, contains a GAIN domain, which is otherwise only found in aGPCRs. In this review, we assess the potential of aGPCRs as therapeutic targets for kidney disease. For this purpose we have summarized the available literature and analyzed data from the databases The Human Protein Atlas, EURExpress, Nephroseq, FireBrowse, cBioPortal for Cancer Genomics and the National Cancer Institute Genomic Data Commons data portal (NCIGDC). Our data indicate that most aGPCRs are expressed in different spatio-temporal patterns during kidney development and that altered aGPCR expression is associated with a variety of kidney diseases including CKD, diabetic nephropathy, lupus nephritis as well as renal cell carcinoma. We conclude that aGPCRs present a promising new class of therapeutic targets and/or might be useful as diagnostic markers in kidney disease.
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Affiliation(s)
- Salvador Cazorla-Vázquez
- Department of Nephropathology, Experimental Renal and Cardiovascular Research, Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Felix B Engel
- Department of Nephropathology, Experimental Renal and Cardiovascular Research, Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
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84
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Modarres HP, Janmaleki M, Novin M, Saliba J, El-Hajj F, RezayatiCharan M, Seyfoori A, Sadabadi H, Vandal M, Nguyen MD, Hasan A, Sanati-Nezhad A. In vitro models and systems for evaluating the dynamics of drug delivery to the healthy and diseased brain. J Control Release 2018; 273:108-130. [PMID: 29378233 DOI: 10.1016/j.jconrel.2018.01.024] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2017] [Revised: 01/22/2018] [Accepted: 01/23/2018] [Indexed: 12/12/2022]
Abstract
The blood-brain barrier (BBB) plays a crucial role in maintaining brain homeostasis and transport of drugs to the brain. The conventional animal and Transwell BBB models along with emerging microfluidic-based BBB-on-chip systems have provided fundamental functionalities of the BBB and facilitated the testing of drug delivery to the brain tissue. However, developing biomimetic and predictive BBB models capable of reasonably mimicking essential characteristics of the BBB functions is still a challenge. In addition, detailed analysis of the dynamics of drug delivery to the healthy or diseased brain requires not only biomimetic BBB tissue models but also new systems capable of monitoring the BBB microenvironment and dynamics of barrier function and delivery mechanisms. This review provides a comprehensive overview of recent advances in microengineering of BBB models with different functional complexity and mimicking capability of healthy and diseased states. It also discusses new technologies that can make the next generation of biomimetic human BBBs containing integrated biosensors for real-time monitoring the tissue microenvironment and barrier function and correlating it with the dynamics of drug delivery. Such integrated system addresses important brain drug delivery questions related to the treatment of brain diseases. We further discuss how the combination of in vitro BBB systems, computational models and nanotechnology supports for characterization of the dynamics of drug delivery to the brain.
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Affiliation(s)
- Hassan Pezeshgi Modarres
- BioMEMS and Bioinspired Microfluidic Laboratory, Department of Mechanical and Manufacturing Engineering, University of Calgary, Calgary, Canada; Center for BioEngineering Research and Education, University of Calgary, Calgary, Canada
| | - Mohsen Janmaleki
- BioMEMS and Bioinspired Microfluidic Laboratory, Department of Mechanical and Manufacturing Engineering, University of Calgary, Calgary, Canada; Center for BioEngineering Research and Education, University of Calgary, Calgary, Canada
| | - Mana Novin
- BioMEMS and Bioinspired Microfluidic Laboratory, Department of Mechanical and Manufacturing Engineering, University of Calgary, Calgary, Canada; Center for BioEngineering Research and Education, University of Calgary, Calgary, Canada
| | - John Saliba
- Biomedical Engineering, Department of Mechanical Engineering, Faculty of Engineering and Architecture, American University of Beirut, Beirut 1107 2020, Lebanon
| | - Fatima El-Hajj
- Biomedical Engineering, Department of Mechanical Engineering, Faculty of Engineering and Architecture, American University of Beirut, Beirut 1107 2020, Lebanon
| | - Mahdi RezayatiCharan
- Breast Cancer Research Center (BCRC), ACECR, Tehran, Iran; School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran
| | - Amir Seyfoori
- Breast Cancer Research Center (BCRC), ACECR, Tehran, Iran; School of Metallurgy and Materials Engineering, College of Engineering, University of Tehran, Tehran, Iran
| | - Hamid Sadabadi
- BioMEMS and Bioinspired Microfluidic Laboratory, Department of Mechanical and Manufacturing Engineering, University of Calgary, Calgary, Canada; Center for BioEngineering Research and Education, University of Calgary, Calgary, Canada
| | - Milène Vandal
- Departments of Clinical Neurosciences, Cell Biology and Anatomy, Biochemistry and Molecular Biology, University of Calgary, Calgary, Canada
| | - Minh Dang Nguyen
- Departments of Clinical Neurosciences, Cell Biology and Anatomy, Biochemistry and Molecular Biology, University of Calgary, Calgary, Canada
| | - Anwarul Hasan
- Biomedical Engineering, Department of Mechanical Engineering, Faculty of Engineering and Architecture, American University of Beirut, Beirut 1107 2020, Lebanon; Department of Mechanical and Industrial Engineering, College of Engineering, Qatar University, Doha, 2713, Qatar
| | - Amir Sanati-Nezhad
- BioMEMS and Bioinspired Microfluidic Laboratory, Department of Mechanical and Manufacturing Engineering, University of Calgary, Calgary, Canada; Center for BioEngineering Research and Education, University of Calgary, Calgary, Canada.
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85
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Driehuis E, Clevers H. WNT signalling events near the cell membrane and their pharmacological targeting for the treatment of cancer. Br J Pharmacol 2017; 174:4547-4563. [PMID: 28244067 PMCID: PMC5727251 DOI: 10.1111/bph.13758] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 02/16/2017] [Accepted: 02/18/2017] [Indexed: 12/16/2022] Open
Abstract
WNT signalling is an essential signalling pathway for all multicellular animals. Although first described more than 30 years ago, new components and regulators of the pathway are still being discovered. Considering its importance in both embryonic development and adult homeostasis, it is not surprising that this pathway is often deregulated in human diseases such as cancer. Recently, it became clear that in addition to cytoplasmic components such as β-catenin, other, membrane-bound or extracellular, components of the WNT pathway are also altered in cancer. This review gives an overview of the recent discoveries on WNT signalling events near the cell membrane. Furthermore, membrane-associated components of the WNT pathway, which are more accessible for therapeutic intervention, as well therapeutic approaches that already target those components will be discussed. In this way, we hope to stimulate the development of effective anti-cancer therapies that target this fascinating pathway. LINKED ARTICLES This article is part of a themed section on WNT Signalling: Mechanisms and Therapeutic Opportunities. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.24/issuetoc.
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Affiliation(s)
- Else Driehuis
- Hubrecht InstituteRoyal Netherlands Academy of Arts and Sciences (KNAW)UtrechtThe Netherlands
- University medical center (UMC)UtrechtThe Netherlands
| | - Hans Clevers
- Hubrecht InstituteRoyal Netherlands Academy of Arts and Sciences (KNAW)UtrechtThe Netherlands
- University medical center (UMC)UtrechtThe Netherlands
- Princess Maxime Center (PMC)UtrechtThe Netherlands
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86
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Abstract
The adhesion G protein-coupled receptors (aGPCRs) are an evolutionarily ancient family of receptors that play key roles in many different physiological processes. These receptors are notable for their exceptionally long ectodomains, which span several hundred to several thousand amino acids and contain various adhesion-related domains, as well as a GPCR autoproteolysis-inducing (GAIN) domain. The GAIN domain is conserved throughout almost the entire family and undergoes autoproteolysis to cleave the receptors into two noncovalently-associated protomers. Recent studies have revealed that the signaling activity of aGPCRs is largely determined by changes in the interactions among these protomers. We review recent advances in understanding aGPCR activation mechanisms and discuss the physiological roles and pharmacological properties of aGPCRs, with an eye toward the potential utility of these receptors as drug targets.
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Affiliation(s)
- Ryan H Purcell
- Department of Pharmacology, Emory University School of Medicine, Atlanta, Georgia, 30322, USA;
| | - Randy A Hall
- Department of Pharmacology, Emory University School of Medicine, Atlanta, Georgia, 30322, USA;
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87
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Zhang G, Wang R, Cheng K, Li Q, Wang Y, Zhang R, Qin X. Repulsive Guidance Molecule a Inhibits Angiogenesis by Downregulating VEGF and Phosphorylated Focal Adhesion Kinase In Vitro. Front Neurol 2017; 8:504. [PMID: 29018403 PMCID: PMC5623191 DOI: 10.3389/fneur.2017.00504] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Accepted: 09/08/2017] [Indexed: 01/13/2023] Open
Abstract
Repulsive guidance molecule a (RGMa) is a major neuron guidance factor in central nervous systems. We previously found that inhibition of RGMa could greatly enhance neural function rehabilitation in rats after MCAO/reperfusion. Neuron guidance factors are often regulators of angiogenesis. However, the effect of RGMa on angiogenesis and its mechanisms remain to be determined. Here, we investigated the effect of RGMa on endothelial cell (EC) proliferation, migration, tube formation, and cytoskeleton reassembly. The addition of recombinant RGMa significantly decreased the proliferation, migration, and tube formation of ECs. It also decreased the level of phosphorylated focal adhesion kinase (p-FAK Tyr397). Furthermore, the F-actin of the cytoskeleton assembly was obviously suppressed, with decreased filopodia and lamellipodia after the addition of RGMa. Knockout of neogenin or Unc5b significantly diminished RGMa’s inhibition of EC migration, tube formation, and cytoskeleton reassembly. RGMa-induced p-FAK (Tyr397) decrease was also abolished by knockout of neogenin or Unc5b. These results indicate that RGMa may be a negative regulator of angiogenesis through downregulating VEGF and p-FAK (Tyr397) via neogenin and Unc5b in vitro.
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Affiliation(s)
- Gang Zhang
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Rong Wang
- Department of Gastrointestinal Surgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Ke Cheng
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Qi Li
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Yu Wang
- Department of Neurosurgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Rongrong Zhang
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Xinyue Qin
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
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88
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Spadoni I, Fornasa G, Rescigno M. Organ-specific protection mediated by cooperation between vascular and epithelial barriers. Nat Rev Immunol 2017; 17:761-773. [PMID: 28869253 DOI: 10.1038/nri.2017.100] [Citation(s) in RCA: 98] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Immune privilege is a complex process that protects organs from immune-mediated attack and damage. It is accomplished by a series of cellular barriers that both control immune cell entry and promote the development of tolerogenic immune cells. In this Review, we describe the vascular endothelial and epithelial barriers in organs that are commonly considered to be immune privileged, such as the brain and the eye. We compare these classical barriers with barriers in the intestine, which share features with barriers of immune-privileged organs, such as the capacity to induce tolerance and to protect from external insults. We suggest that when intestinal barriers break down, disruption of other barriers at distant sites can ensue, and this may underlie the development of various neurological, metabolic and intestinal disorders.
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Affiliation(s)
- Ilaria Spadoni
- Department of Experimental Oncology, European Institute of Oncology, 20139 Milan, Italy
| | - Giulia Fornasa
- Department of Experimental Oncology, European Institute of Oncology, 20139 Milan, Italy
| | - Maria Rescigno
- Department of Experimental Oncology, European Institute of Oncology, 20139 Milan, Italy.,Dipartimento di Scienze della Salute, Università degli Studi di Milano, 20122 Milan, Italy
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89
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Cho C, Smallwood PM, Nathans J. Reck and Gpr124 Are Essential Receptor Cofactors for Wnt7a/Wnt7b-Specific Signaling in Mammalian CNS Angiogenesis and Blood-Brain Barrier Regulation. Neuron 2017; 95:1056-1073.e5. [PMID: 28803732 PMCID: PMC5586543 DOI: 10.1016/j.neuron.2017.07.031] [Citation(s) in RCA: 107] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 06/14/2017] [Accepted: 07/26/2017] [Indexed: 10/19/2022]
Abstract
Reck, a GPI-anchored membrane protein, and Gpr124, an orphan GPCR, have been implicated in Wnt7a/Wnt7b signaling in the CNS vasculature. We show here that vascular endothelial cell (EC)-specific reduction in Reck impairs CNS angiogenesis and that EC-specific postnatal loss of Reck, combined with loss of Norrin, impairs blood-brain barrier (BBB) maintenance. The most N-terminal domain of Reck binds to the leucine-rich repeat (LRR) and immunoglobulin (Ig) domains of Gpr124, and weakening this interaction by targeted mutagenesis reduces Reck/Gpr124 stimulation of Wnt7a signaling in cell culture and impairs CNS angiogenesis. Finally, a soluble Gpr124(LRR-Ig) probe binds to cells expressing Frizzled, Wnt7a or Wnt7b, and Reck, and a soluble Reck(CC1-5) probe binds to cells expressing Frizzled, Wnt7a or Wnt7b, and Gpr124. These experiments indicate that Reck and Gpr124 are part of the cell surface protein complex that transduces Wnt7a- and Wnt7b-specific signals in mammalian CNS ECs to promote angiogenesis and regulate the BBB.
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Affiliation(s)
- Chris Cho
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Philip M Smallwood
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Jeremy Nathans
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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90
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CD146 coordinates brain endothelial cell-pericyte communication for blood-brain barrier development. Proc Natl Acad Sci U S A 2017; 114:E7622-E7631. [PMID: 28827364 DOI: 10.1073/pnas.1710848114] [Citation(s) in RCA: 110] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The blood-brain barrier (BBB) establishes a protective interface between the central neuronal system and peripheral blood circulation and is crucial for homeostasis of the CNS. BBB formation starts when the endothelial cells (ECs) invade the CNS and pericytes are recruited to the nascent vessels during embryogenesis. Despite the essential function of pericyte-EC interaction during BBB development, the molecular mechanisms coordinating the pericyte-EC behavior and communication remain incompletely understood. Here, we report a single cell receptor, CD146, that presents dynamic expression patterns in the cerebrovasculature at the stages of BBB induction and maturation, coordinates the interplay of ECs and pericytes, and orchestrates BBB development spatiotemporally. In mouse brain, CD146 is first expressed in the cerebrovascular ECs of immature capillaries without pericyte coverage; with increased coverage of pericytes, CD146 could only be detected in pericytes, but not in cerebrovascular ECs. Specific deletion of Cd146 in mice ECs resulted in reduced brain endothelial claudin-5 expression and BBB breakdown. By analyzing mice with specific deletion of Cd146 in pericytes, which have defects in pericyte coverage and BBB integrity, we demonstrate that CD146 functions as a coreceptor of PDGF receptor-β to mediate pericyte recruitment to cerebrovascular ECs. Moreover, we found that the attached pericytes in turn down-regulate endothelial CD146 by secreting TGF-β1 to promote further BBB maturation. These results reveal that the dynamic expression of CD146 controls the behavior of ECs and pericytes, thereby coordinating the formation of a mature and stable BBB.
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91
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Augustin HG, Koh GY. Organotypic vasculature: From descriptive heterogeneity to functional pathophysiology. Science 2017; 357:science.aal2379. [DOI: 10.1126/science.aal2379] [Citation(s) in RCA: 351] [Impact Index Per Article: 50.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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92
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Guerra M, Blázquez JL, Rodríguez EM. Blood-brain barrier and foetal-onset hydrocephalus, with a view on potential novel treatments beyond managing CSF flow. Fluids Barriers CNS 2017; 14:19. [PMID: 28701191 PMCID: PMC5508761 DOI: 10.1186/s12987-017-0067-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Accepted: 06/24/2017] [Indexed: 12/12/2022] Open
Abstract
Despite decades of research, no compelling non-surgical therapies have been developed for foetal hydrocephalus. So far, most efforts have pointed to repairing disturbances in the cerebrospinal fluid (CSF) flow and to avoid further brain damage. There are no reports trying to prevent or diminish abnormalities in brain development which are inseparably associated with hydrocephalus. A key problem in the treatment of hydrocephalus is the blood–brain barrier that restricts the access to the brain for therapeutic compounds or systemically grafted cells. Recent investigations have started to open an avenue for the development of a cell therapy for foetal-onset hydrocephalus. Potential cells to be used for brain grafting include: (1) pluripotential neural stem cells; (2) mesenchymal stem cells; (3) genetically-engineered stem cells; (4) choroid plexus cells and (5) subcommissural organ cells. Expected outcomes are a proper microenvironment for the embryonic neurogenic niche and, consequent normal brain development.
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Affiliation(s)
- M Guerra
- Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile.
| | - J L Blázquez
- Departamento de Anatomía e Histología Humana, Facultad de Medicina, Universidad de Salamanca, Salamanca, Spain
| | - E M Rodríguez
- Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile
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93
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Calderón-Zamora L, Ruiz-Hernandez A, Romero-Nava R, León-Sicairos N, Canizalez-Román A, Hong E, Huang F, Villafaña S. Possible involvement of orphan receptors GPR88 and GPR124 in the development of hypertension in spontaneously hypertensive rat. Clin Exp Hypertens 2017; 39:513-519. [PMID: 28678544 DOI: 10.1080/10641963.2016.1273949] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Hypertension (HBP) is a chronic disease characterized by increased blood pressure, which despite several treatments maintains a high morbi-mortality, which suggests that there are other mechanisms involved in this pathology, within which the orphan receptors could be candidates for the treatment of the HBP; these receptors are called orphan receptors because their ligand is unknown. These receptors have been suggested to participate in some pathologies because they are associated with various systems such as GPR88, which has been linked to the dopaminergic system, and GPR124 with angiogenesis, suggesting that these receptors could take part in HBP. Hence, the aim of this work was to study the expression of orphan receptors GPR88 and GPR124 in various tissues of normotensive and hypertensive rats. We used Wistar Kyoto (WKY) and spontaneously hypertensive rat (SHR) of 6-8 and 10-12 weeks of age and we determined systolic blood pressure (SBP), heart rate, as well as mRNA of GPR88 and GPR124 receptors by reverse transcription polymerase chain reaction (RT-PCR) in the aorta, heart, kidney, and brain. Our results showed that GPR88 and GPR124 were expressed in all analyzed tissues, but their expression is dependent on the age and development of HBP because their expression tends to be modified as HBP is established. Therefore, we conclude that GPR88 and GPR124 receptors may be involved in the development or maintenance of high blood pressure.
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Affiliation(s)
- L Calderón-Zamora
- a Laboratorio de Señalización Intracelular, Sección de Posgrado , Escuela Superior de Medicina del Instituto Politécnico Nacional Ciudad de México , México
| | - A Ruiz-Hernandez
- a Laboratorio de Señalización Intracelular, Sección de Posgrado , Escuela Superior de Medicina del Instituto Politécnico Nacional Ciudad de México , México
| | - R Romero-Nava
- a Laboratorio de Señalización Intracelular, Sección de Posgrado , Escuela Superior de Medicina del Instituto Politécnico Nacional Ciudad de México , México
| | - N León-Sicairos
- b CIASaP, Facultad de Medicina , Universidad Autónoma de Sinaloa Culiacán , Sinaloa , México
| | - A Canizalez-Román
- b CIASaP, Facultad de Medicina , Universidad Autónoma de Sinaloa Culiacán , Sinaloa , México
| | - E Hong
- c Departamento de Farmacobiología , Centro de Investigación y de Estudios Avanzados , Ciudad de México , México
| | - F Huang
- d Departamento de Farmacología y Toxicología , Hospital Infantil de México Federico Gómez (HIMFG) , Ciudad de México , México
| | - S Villafaña
- a Laboratorio de Señalización Intracelular, Sección de Posgrado , Escuela Superior de Medicina del Instituto Politécnico Nacional Ciudad de México , México
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94
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Díaz-Coránguez M, Ramos C, Antonetti DA. The inner blood-retinal barrier: Cellular basis and development. Vision Res 2017; 139:123-137. [PMID: 28619516 DOI: 10.1016/j.visres.2017.05.009] [Citation(s) in RCA: 154] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Revised: 05/26/2017] [Accepted: 05/30/2017] [Indexed: 01/01/2023]
Abstract
The blood-retinal barrier (BRB) regulates transport across retinal capillaries maintaining proper neural homeostasis and protecting the neural tissue from potential blood borne toxicity. Loss of the BRB contributes to the pathophysiology of a number of blinding retinal diseases including diabetic retinopathy. In this review, we address the basis of the BRB, including the molecular mechanisms that regulate flux across the retinal vascular bed. The routes of transcellular and paracellular flux are described as well as alterations in these pathways in response to permeabilizing agents in diabetes. Finally, we provide information on exciting new studies that help to elucidate the process of BRB development or barriergenesis and how understanding this process may lead to new opportunities for barrier restoration in diabetic retinopathy.
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Affiliation(s)
- Mónica Díaz-Coránguez
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan, Ann Arbor, MI, United States
| | - Carla Ramos
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan, Ann Arbor, MI, United States
| | - David A Antonetti
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan, Ann Arbor, MI, United States.
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95
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Hernández-Vásquez MN, Adame-García SR, Hamoud N, Chidiac R, Reyes-Cruz G, Gratton JP, Côté JF, Vázquez-Prado J. Cell adhesion controlled by adhesion G protein-coupled receptor GPR124/ADGRA2 is mediated by a protein complex comprising intersectins and Elmo-Dock. J Biol Chem 2017; 292:12178-12191. [PMID: 28600358 DOI: 10.1074/jbc.m117.780304] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 05/30/2017] [Indexed: 11/06/2022] Open
Abstract
Developmental angiogenesis and the maintenance of the blood-brain barrier involve endothelial cell adhesion, which is linked to cytoskeletal dynamics. GPR124 (also known as TEM5/ADGRA2) is an adhesion G protein-coupled receptor family member that plays a pivotal role in brain angiogenesis and in ensuring a tight blood-brain barrier. However, the signaling properties of GPR124 remain poorly defined. Here, we show that ectopic expression of GPR124 promotes cell adhesion, additive to extracellular matrix-dependent effect, coupled with filopodia and lamellipodia formation and an enrichment of a pool of the G protein-coupled receptor at actin-rich cellular protrusions containing VASP, a filopodial marker. Accordingly, GPR124-expressing cells also displayed increased activation of both Rac and Cdc42 GTPases. Mechanistically, we uncover novel direct interactions between endogenous GPR124 and the Rho guanine nucleotide exchange factors Elmo/Dock and intersectin (ITSN). Small fragments of either Elmo or ITSN1 that bind GPR124 blocked GPR124-induced cell adhesion. In addition, Gβγ interacts with the C-terminal tail of GPR124 and promotes the formation of a GPR124-Elmo complex. Furthermore, GPR124 also promotes the activation of the Elmo-Dock complex, as measured by Elmo phosphorylation on a conserved C-terminal tyrosine residue. Interestingly, Elmo and ITSN1 also interact with each other independently of their GPR124-recognition regions. Moreover, endogenous phospho-Elmo and ITSN1 co-localize with GPR124 at lamellipodia of adhering endothelial cells, where GPR124 expression contributes to polarity acquisition during wound healing. Collectively, our results indicate that GPR124 promotes cell adhesion via Elmo-Dock and ITSN. This constitutes a previously unrecognized complex formed of atypical and conventional Rho guanine nucleotide exchange factors for Rac and Cdc42 that is putatively involved in GPR124-dependent angiogenic responses.
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Affiliation(s)
- Magda Nohemí Hernández-Vásquez
- Department of Pharmacology, Center for Research and Advanced Studies of the National Polytechnic Institute (CINVESTAV-IPN), Mexico City 14740, Mexico
| | - Sendi Rafael Adame-García
- Department of Cell Biology, Center for Research and Advanced Studies of the National Polytechnic Institute (CINVESTAV-IPN), Mexico City 14740, Mexico
| | - Noumeira Hamoud
- Institut de Recherches Cliniques de Montréal, Université de Montréal, Montreal, Quebec H3T 1J4, Canada
| | - Rony Chidiac
- Department of Pharmacology, Faculty of Medicine, Université de Montréal, Montreal, Quebec H3T 1J4, Canada
| | - Guadalupe Reyes-Cruz
- Department of Cell Biology, Center for Research and Advanced Studies of the National Polytechnic Institute (CINVESTAV-IPN), Mexico City 14740, Mexico
| | - Jean Philippe Gratton
- Department of Pharmacology, Faculty of Medicine, Université de Montréal, Montreal, Quebec H3T 1J4, Canada
| | - Jean-François Côté
- Institut de Recherches Cliniques de Montréal, Université de Montréal, Montreal, Quebec H3T 1J4, Canada
| | - José Vázquez-Prado
- Department of Pharmacology, Center for Research and Advanced Studies of the National Polytechnic Institute (CINVESTAV-IPN), Mexico City 14740, Mexico.
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96
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Thomas M, Snead D, Mitchell D. An investigation into the potential role of brain angiogenesis inhibitor protein 3 (BAI3) in the tumorigenesis of small-cell carcinoma: a review of the surrounding literature. J Recept Signal Transduct Res 2017; 37:325-334. [PMID: 28537194 DOI: 10.1080/10799893.2017.1328441] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Brain angiogenesis inhibitor protein 3 (BAI3) is from the adhesion group of seven-transmembrane spanning G protein-coupled receptors (GPCRs) and has been identified via gene expression profiling as being upregulated in small-cell lung cancer (SCLC) tumors. It has subsequently been validated as a sensitive and specific immunohistochemical marker for SCLC, helping to differentiate these tumors from morphologically similar large-cell neuroendocrine (LCNEC) malignancies. It is, however, still unclear as to the role BAI3 proteins might play in SCLC and indeed how they might contribute to tumorigenesis. Interestingly, the pattern of staining observed on immunohistochemistry was in fact nuclear as opposed to the membranous staining pattern expected of transmembrane-bound molecules. This fact has lead the authors to believe that the protein receptor is structurally altered in SCLC and that this modification may confer different behavioral properties that contribute toward tumorigenesis. Nuclear localization is not unique to BAI3 and has been reported in a number of GPCRs and frequently correlates with survival outcomes. BAI3 has the potential to act as target for pharmaceutical intervention inline with developing trends in molecular pathology aiming to provide personalized, treatment regimes based on tumor-specific mutation profiles. The adhesion group of the GPCR superfamily is still poorly understood. We present a review of the existing literature regarding the role they play in both physiological and disease states and the mechanisms by which they influence a range of cellular processes.
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Affiliation(s)
- Michael Thomas
- a Department of Histopathology , University Hospitals Coventry and Warwickshire , Coventry , UK
| | - David Snead
- a Department of Histopathology , University Hospitals Coventry and Warwickshire , Coventry , UK
| | - Daniel Mitchell
- b Department of Translational Medicine , University of Warwick , Coventry , UK
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97
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Haddad-Tóvolli R, Dragano NRV, Ramalho AFS, Velloso LA. Development and Function of the Blood-Brain Barrier in the Context of Metabolic Control. Front Neurosci 2017; 11:224. [PMID: 28484368 PMCID: PMC5399017 DOI: 10.3389/fnins.2017.00224] [Citation(s) in RCA: 128] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Accepted: 04/04/2017] [Indexed: 12/21/2022] Open
Abstract
Under physiological conditions, the brain consumes over 20% of the whole body energy supply. The blood-brain barrier (BBB) allows dynamic interactions between blood capillaries and the neuronal network in order to provide an adequate control of molecules that are transported in and out of the brain. Alterations in the BBB structure and function affecting brain accessibility to nutrients and exit of toxins are found in a number of diseases, which in turn may disturb brain function and nutrient signaling. In this review we explore the major advances obtained in the understanding of the BBB development and how its structure impacts on function. Furthermore, we focus on the particularities of the barrier permeability in the hypothalamus, its role in metabolic control and the potential impact of hypothalamic BBB abnormities in metabolic related diseases.
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Affiliation(s)
- Roberta Haddad-Tóvolli
- Laboratory of Cell Signaling and Obesity and Comorbidities Research Center, Faculty of Medical Sciences, University of CampinasCampinas, Brazil
| | | | | | - Licio A. Velloso
- Laboratory of Cell Signaling and Obesity and Comorbidities Research Center, Faculty of Medical Sciences, University of CampinasCampinas, Brazil
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98
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Umans RA, Henson HE, Mu F, Parupalli C, Ju B, Peters JL, Lanham KA, Plavicki JS, Taylor MR. CNS angiogenesis and barriergenesis occur simultaneously. Dev Biol 2017; 425:101-108. [PMID: 28365243 DOI: 10.1016/j.ydbio.2017.03.017] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Revised: 02/24/2017] [Accepted: 03/18/2017] [Indexed: 01/04/2023]
Abstract
The blood-brain barrier (BBB) plays a vital role in the central nervous system (CNS). A comprehensive understanding of BBB development has been hampered by difficulties in observing the differentiation of brain endothelial cells (BECs) in real-time. Here, we generated two transgenic zebrafish line, Tg(glut1b:mCherry) and Tg(plvap:EGFP), to serve as in vivo reporters of BBB development. We showed that barriergenesis (i.e. the induction of BEC differentiation) occurs immediately as endothelial tips cells migrate into the brain parenchyma. Using the Tg(glut1b:mCherry) transgenic line, we performed a genetic screen and identified a zebrafish mutant with a nonsense mutation in gpr124, a gene known to play a role in CNS angiogenesis and BBB development. We also showed that our transgenic plvap:EGFP line, a reporter of immature brain endothelium, is initially expressed in newly formed brain endothelial cells, but subsides during BBB maturation. Our results demonstrate the ability to visualize the in vivo differentiation of brain endothelial cells into the BBB phenotype and establish that CNS angiogenesis and barriergenesis occur simultaneously.
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Affiliation(s)
- Robyn A Umans
- Department of Chemical Biology & Therapeutics, St. Jude Children's Research Hospital, Memphis, TN, USA; Integrated Program in Biomedical Sciences, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Hannah E Henson
- Department of Chemical Biology & Therapeutics, St. Jude Children's Research Hospital, Memphis, TN, USA; Integrated Program in Biomedical Sciences, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Fangzhou Mu
- Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin, Madison, WI, USA
| | - Chaithanyarani Parupalli
- Department of Chemical Biology & Therapeutics, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Bensheng Ju
- Department of Chemical Biology & Therapeutics, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Jennifer L Peters
- Cell and Tissue Imaging, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Kevin A Lanham
- Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin, Madison, WI, USA
| | - Jessica S Plavicki
- Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin, Madison, WI, USA
| | - Michael R Taylor
- Department of Chemical Biology & Therapeutics, St. Jude Children's Research Hospital, Memphis, TN, USA; Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin, Madison, WI, USA.
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99
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Gpr124 is essential for blood-brain barrier integrity in central nervous system disease. Nat Med 2017; 23:450-460. [PMID: 28288111 DOI: 10.1038/nm.4309] [Citation(s) in RCA: 148] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 02/21/2017] [Indexed: 12/14/2022]
Abstract
Although blood-brain barrier (BBB) compromise is central to the etiology of diverse central nervous system (CNS) disorders, endothelial receptor proteins that control BBB function are poorly defined. The endothelial G-protein-coupled receptor (GPCR) Gpr124 has been reported to be required for normal forebrain angiogenesis and BBB function in mouse embryos, but the role of this receptor in adult animals is unknown. Here Gpr124 conditional knockout (CKO) in the endothelia of adult mice did not affect homeostatic BBB integrity, but resulted in BBB disruption and microvascular hemorrhage in mouse models of both ischemic stroke and glioblastoma, accompanied by reduced cerebrovascular canonical Wnt-β-catenin signaling. Constitutive activation of Wnt-β-catenin signaling fully corrected the BBB disruption and hemorrhage defects of Gpr124-CKO mice, with rescue of the endothelial gene tight junction, pericyte coverage and extracellular-matrix deficits. We thus identify Gpr124 as an endothelial GPCR specifically required for endothelial Wnt signaling and BBB integrity under pathological conditions in adult mice. This finding implicates Gpr124 as a potential therapeutic target for human CNS disorders characterized by BBB disruption.
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100
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Himmels P, Paredes I, Adler H, Karakatsani A, Luck R, Marti HH, Ermakova O, Rempel E, Stoeckli ET, Ruiz de Almodóvar C. Motor neurons control blood vessel patterning in the developing spinal cord. Nat Commun 2017; 8:14583. [PMID: 28262664 PMCID: PMC5343469 DOI: 10.1038/ncomms14583] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Accepted: 01/13/2017] [Indexed: 12/16/2022] Open
Abstract
Formation of a precise vascular network within the central nervous system is of critical importance to assure delivery of oxygen and nutrients and for accurate functionality of neuronal networks. Vascularization of the spinal cord is a highly stereotypical process. However, the guidance cues controlling blood vessel patterning in this organ remain largely unknown. Here we describe a new neuro-vascular communication mechanism that controls vessel guidance in the developing spinal cord. We show that motor neuron columns remain avascular during a developmental time window, despite expressing high levels of the pro-angiogenic vascular endothelial growth factor (VEGF). We describe that motor neurons express the VEGF trapping receptor sFlt1 via a Neuropilin-1-dependent mechanism. Using a VEGF gain-of-function approach in mice and a motor neuron-specific sFlt1 loss-of-function approach in chicken, we show that motor neurons control blood vessel patterning by an autocrine mechanism that titrates motor neuron-derived VEGF via their own expression of sFlt1. The guidance cues regulating blood vessel patterning in the central nervous system remain unclear. Here, the authors show in mice and chicken developing spinal cord that motor neurons control blood vessel patterning by an autocrine mechanism titrating VEGF via the expression of its trapping receptor sFlt1.
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Affiliation(s)
- Patricia Himmels
- Biochemistry Center, Heidelberg University, 69120 Heidelberg, Germany.,Interdisciplinary Center for Neurosciences, Heidelberg University, 69120 Heidelberg, Germany
| | - Isidora Paredes
- Biochemistry Center, Heidelberg University, 69120 Heidelberg, Germany.,Interdisciplinary Center for Neurosciences, Heidelberg University, 69120 Heidelberg, Germany
| | - Heike Adler
- Biochemistry Center, Heidelberg University, 69120 Heidelberg, Germany.,Interdisciplinary Center for Neurosciences, Heidelberg University, 69120 Heidelberg, Germany
| | - Andromachi Karakatsani
- Biochemistry Center, Heidelberg University, 69120 Heidelberg, Germany.,Interdisciplinary Center for Neurosciences, Heidelberg University, 69120 Heidelberg, Germany
| | - Robert Luck
- Biochemistry Center, Heidelberg University, 69120 Heidelberg, Germany.,Interdisciplinary Center for Neurosciences, Heidelberg University, 69120 Heidelberg, Germany
| | - Hugo H Marti
- Institute of Physiology and Pathophysiology, Heidelberg University, 69120 Heidelberg, Germany
| | - Olga Ermakova
- Department of Stem Cell Biology, Centre for Organismal Studies, Heidelberg University, 69120 Heidelberg, Germany
| | - Eugen Rempel
- Department of Stem Cell Biology, Centre for Organismal Studies, Heidelberg University, 69120 Heidelberg, Germany
| | - Esther T Stoeckli
- Institute of Molecular Life Sciences, University of Zurich, 8057 Zurich, Switzerland
| | - Carmen Ruiz de Almodóvar
- Biochemistry Center, Heidelberg University, 69120 Heidelberg, Germany.,Interdisciplinary Center for Neurosciences, Heidelberg University, 69120 Heidelberg, Germany
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