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Chen Y, Huang X, Chen H, Yi C. An easy-to-perform method for microvessel isolation and primary brain endothelial cell culture to study Alzheimer's disease. Heliyon 2024; 10:e33077. [PMID: 38994107 PMCID: PMC11238044 DOI: 10.1016/j.heliyon.2024.e33077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Revised: 06/13/2024] [Accepted: 06/13/2024] [Indexed: 07/13/2024] Open
Abstract
Dysfunction of the blood-brain barrier (BBB) has been increasingly recognised as a critical early event in Alzheimer's disease (AD) pathophysiology. Central to this mechanism is the impaired function of brain endothelial cells (BECs), the primary structural constituents of the BBB, the study of which is imperative for understanding AD pathophysiology. However, the published methods to isolate BECs are time-consuming and have a low success rate. Here, we developed a rapid and streamlined protocol for BEC isolation without using transgenic reporters, flow cytometry, and magnetic beads, which are essential for existing methods. Using this novel protocol, we isolated high-purity BECs from cell clusters of cortical microvessels from wild-type and APPswe/PS1dE9 (APP/PS1, a classical AD model) mice at 2, 4 and 9 months of age. Reduced levels of tight junction proteins Claudin-5 and Zonula Occludens-1, as well as glucose transporter 1, were observed in the isolated cortical microvessels from APP/PS1 mice and amyloid-β (Aβ) oligomer-treated BECs from wild-type mice. Trans-well permeability assay showed increased FITC-dextran leakage in BECs treated with Aβ, suggesting impaired BBB permeability. BECs obtained using our novel protocol can undergo various experimental analyses, including immunofluorescence staining, western blotting, real-time PCR, and trans-well permeability assay. In conclusion, our novel protocol represents a reliable and valuable tool for in vitro modelling BBB to study AD-related mechanisms and develop targeted therapeutic strategies.
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Affiliation(s)
- Yang Chen
- Research Centre, Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen, China
| | - Xiaomin Huang
- Research Centre, Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen, China
| | - Hui Chen
- School of Life Sciences, Faculty of Science, University of Technology Sydney, Ultimo, NSW, 2007, Australia
| | - Chenju Yi
- Research Centre, Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen, China
- Shenzhen Key Laboratory of Chinese Medicine Active Substance Screening and Translational Research, Shenzhen, 518107, China
- Guangdong Provincial Key Laboratory of Brain Function and Disease, Guangzhou, China
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2
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Mi J, Sun A, Härtel L, Dilling C, Meybohm P, Burek M. Isolation of Capillaries from Small Amounts of Mouse Brain Tissue. Methods Mol Biol 2024; 2761:27-38. [PMID: 38427226 DOI: 10.1007/978-1-0716-3662-6_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2024]
Abstract
The integrity of the blood-brain barrier (BBB) is essential for the normal functioning of the central nervous system (CNS). Isolated brain capillaries are essential for analyzing changes in protein and gene expression at the BBB under physiological and pathological conditions. The standard methods for isolating brain capillaries require the use of at least one or more mouse brains in order to obtain sufficient quantity and purity of brain capillaries. Here, we describe an optimized protocol for isolating and purifying capillaries from tiny amounts of mouse cerebral cortex using manual homogenization, density gradient centrifugation, and filtration while preserving the structural integrity and functional activity of microvessel fragments. Western blotting showed that proteins expressed at the BBB were enriched in mouse brain capillaries isolated by the optimized method compared to cerebral cortex protein homogenates. This approach can be used for the analysis of a variety of rare mouse genetic models and can also help the investigators to understand regional differences in susceptibility to pathological phenomena such as ischemia and traumatic brain injury. This will allow the investigators to better understand the physiology and pathology of the BBB.
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Affiliation(s)
- Junqiao Mi
- Department of Anaesthesiology, Intensive Care, Emergency and Pain Medicine, University Hospital Würzburg, Würzburg, Germany
- Graduate School of Life Sciences, Julius-Maximilians-University Würzburg, Würzburg, Germany
| | - Aili Sun
- Department of Anaesthesiology, Intensive Care, Emergency and Pain Medicine, University Hospital Würzburg, Würzburg, Germany
| | - Laura Härtel
- Department of Anaesthesiology, Intensive Care, Emergency and Pain Medicine, University Hospital Würzburg, Würzburg, Germany
| | - Christina Dilling
- Department of Anaesthesiology, Intensive Care, Emergency and Pain Medicine, University Hospital Würzburg, Würzburg, Germany
| | - Patrick Meybohm
- Department of Anaesthesiology, Intensive Care, Emergency and Pain Medicine, University Hospital Würzburg, Würzburg, Germany
| | - Malgorzata Burek
- Department of Anaesthesiology, Intensive Care, Emergency and Pain Medicine, University Hospital Würzburg, Würzburg, Germany.
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3
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Tonami K, Hayashi T, Uchijima Y, Kanai M, Yura F, Mada J, Sugahara K, Kurihara Y, Kominami Y, Ushijima T, Takubo N, Liu X, Tozawa H, Kanai Y, Tokihiro T, Kurihara H. Coordinated linear and rotational movements of endothelial cells compartmentalized by VE-cadherin drive angiogenic sprouting. iScience 2023; 26:107051. [PMID: 37426350 PMCID: PMC10329149 DOI: 10.1016/j.isci.2023.107051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 04/22/2023] [Accepted: 06/01/2023] [Indexed: 07/11/2023] Open
Abstract
Angiogenesis is a sequential process to extend new blood vessels from preexisting ones by sprouting and branching. During angiogenesis, endothelial cells (ECs) exhibit inhomogeneous multicellular behaviors referred to as "cell mixing," in which ECs repetitively exchange their relative positions, but the underlying mechanism remains elusive. Here we identified the coordinated linear and rotational movements potentiated by cell-cell contact as drivers of sprouting angiogenesis using in vitro and in silico approaches. VE-cadherin confers the coordinated linear motility that facilitated forward sprout elongation, although it is dispensable for rotational movement, which was synchronous without VE-cadherin. Mathematical modeling recapitulated the EC motility in the two-cell state and angiogenic morphogenesis with the effects of VE-cadherin-knockout. Finally, we found that VE-cadherin-dependent EC compartmentalization potentiated branch elongations, and confirmed this by mathematical simulation. Collectively, we propose a way to understand angiogenesis, based on unique EC behavioral properties that are partially dependent on VE-cadherin function.
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Affiliation(s)
- Kazuo Tonami
- Department of Physiological Chemistry and Metabolism, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Chiyoda-ku, Tokyo 102-0076, Japan
| | - Tatsuya Hayashi
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Chiyoda-ku, Tokyo 102-0076, Japan
- Graduate School of Mathematical Science, The University of Tokyo, 3-8-1, Komaba, Meguro-ku, Tokyo 153-8914, Japan
- Faculty of Science and Engineering, Chuo University, 1-13-27 Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan
| | - Yasunobu Uchijima
- Department of Physiological Chemistry and Metabolism, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Masahiro Kanai
- Department of Education and Creation Engineering, Kurume Institute of Technology, 2228-66 Kamitsu-machi, Kurume, Fukuoka 830-0052, Japan
| | - Fumitaka Yura
- Department of Complex and Intelligent Systems, School of Systems Information Science, Future University Hakodate, 116-2 Kamedanakano-cho, Hakodate, Hokkaido 041-8655, Japan
| | - Jun Mada
- College of Industrial Technology, Nihon University, 2-11-1 Shin-ei, Narashino, Chiba 275-8576, Japan
| | - Kei Sugahara
- Department of Physiological Chemistry and Metabolism, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Yukiko Kurihara
- Department of Physiological Chemistry and Metabolism, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Yuri Kominami
- Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1, Yayoi, Bunkyo-ku, Tokyo 113-865, Japan
| | - Toshiyuki Ushijima
- Department of Physiological Chemistry and Metabolism, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Naoko Takubo
- Department of Physiological Chemistry and Metabolism, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Chiyoda-ku, Tokyo 102-0076, Japan
- Isotope Science Center, The University of Tokyo, 2-11-16, Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan
| | - Xiaoxiao Liu
- Department of Physiological Chemistry and Metabolism, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Hideto Tozawa
- Department of Chemistry, Graduate School of Science, the University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Yoshimitsu Kanai
- Cell Biology and Anatomy, Graduate School of Medicine, Wakayama Medical University, 811-1 Kimiidera, Wakayama 641-8509, Japan
| | - Tetsuji Tokihiro
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Chiyoda-ku, Tokyo 102-0076, Japan
- Graduate School of Mathematical Science, The University of Tokyo, 3-8-1, Komaba, Meguro-ku, Tokyo 153-8914, Japan
- Department of Mathematical Engineering, Faculty of Engineering, Musashino University, 3-3-3 Ariake, Koto-ku, Tokyo 135-8181, Japan
| | - Hiroki Kurihara
- Department of Physiological Chemistry and Metabolism, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Chiyoda-ku, Tokyo 102-0076, Japan
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4
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Samuels JD, Lotstein ML, Lehmann ML, Elkahloun AG, Banerjee S, Herkenham M. Chronic social defeat alters brain vascular-associated cell gene expression patterns leading to vascular dysfunction and immune system activation. J Neuroinflammation 2023; 20:154. [PMID: 37380974 DOI: 10.1186/s12974-023-02827-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Accepted: 06/06/2023] [Indexed: 06/30/2023] Open
Abstract
Brain vascular integrity is critical for brain health, and its disruption is implicated in many brain pathologies, including psychiatric disorders. Brain-vascular barriers are a complex cellular landscape composed of endothelial, glial, mural, and immune cells. Yet currently, little is known about these brain vascular-associated cells (BVACs) in health and disease. Previously, we demonstrated that 14 days of chronic social defeat (CSD), a mouse paradigm that produces anxiety and depressive-like behaviors, causes cerebrovascular damage in the form of scattered microbleeds. Here, we developed a technique to isolate barrier-related cells from the mouse brain and subjected the isolated cells to single-cell RNA sequencing. Using this isolation technique, we found an enrichment in BVAC populations, including distinct subsets of endothelial and microglial cells. In CSD compared to non-stress, home-cage control, differential gene expression patterns disclosed biological pathways involving vascular dysfunction, vascular healing, and immune system activation. Overall, our work demonstrates a unique technique to study BVAC populations from fresh brain tissue and suggests that neurovascular dysfunction is a key driver of psychosocial stress-induced brain pathology.
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Affiliation(s)
- Joshua D Samuels
- Section on Functional Neuroanatomy, Intramural Research Program, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, 20892, USA.
- Neuroscience Graduate Program, Department of Neuroscience, Center for Brain Immunology and Glia, University of Virginia, 409 Lane Road, MR-4 6154, Charlottesville, VA, 22908, USA.
| | - Madison L Lotstein
- Section on Functional Neuroanatomy, Intramural Research Program, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Michael L Lehmann
- Section on Functional Neuroanatomy, Intramural Research Program, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Abdel G Elkahloun
- Cancer Genetics and Comparative Genomics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Subhadra Banerjee
- Flow Cytometry Core, Laboratory of Genome Integrity, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Miles Herkenham
- Section on Functional Neuroanatomy, Intramural Research Program, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, 20892, USA
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5
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Kisler K, Sagare AP, Lazic D, Bazzi S, Lawson E, Hsu CJ, Wang Y, Ramanathan A, Nelson AR, Zhao Z, Zlokovic BV. Anti-malaria drug artesunate prevents development of amyloid-β pathology in mice by upregulating PICALM at the blood-brain barrier. Mol Neurodegener 2023; 18:7. [PMID: 36707892 PMCID: PMC9883925 DOI: 10.1186/s13024-023-00597-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Accepted: 01/13/2023] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND PICALM is one of the most significant susceptibility factors for Alzheimer's disease (AD). In humans and mice, PICALM is highly expressed in brain endothelium. PICALM endothelial levels are reduced in AD brains. PICALM controls several steps in Aβ transcytosis across the blood-brain barrier (BBB). Its loss from brain endothelium in mice diminishes Aβ clearance at the BBB, which worsens Aβ pathology, but is reversible by endothelial PICALM re-expression. Thus, increasing PICALM at the BBB holds potential to slow down development of Aβ pathology. METHODS To identify a drug that could increase PICALM expression, we screened a library of 2007 FDA-approved drugs in HEK293t cells expressing luciferase driven by a human PICALM promoter, followed by a secondary mRNA screen in human Eahy926 endothelial cell line. In vivo studies with the lead hit were carried out in Picalm-deficient (Picalm+/-) mice, Picalm+/-; 5XFAD mice and Picalmlox/lox; Cdh5-Cre; 5XFAD mice with endothelial-specific Picalm knockout. We studied PICALM expression at the BBB, Aβ pathology and clearance from brain to blood, cerebral blood flow (CBF) responses, BBB integrity and behavior. RESULTS Our screen identified anti-malaria drug artesunate as the lead hit. Artesunate elevated PICALM mRNA and protein levels in Eahy926 endothelial cells and in vivo in brain capillaries of Picalm+/- mice by 2-3-fold. Artesunate treatment (32 mg/kg/day for 2 months) of 3-month old Picalm+/-; 5XFAD mice compared to vehicle increased brain capillary PICALM levels by 2-fold, and reduced Aβ42 and Aβ40 levels and Aβ and thioflavin S-load in the cortex and hippocampus, and vascular Aβ load by 34-51%. Artesunate also increased circulating Aβ42 and Aβ40 levels by 2-fold confirming accelerated Aβ clearance from brain to blood. Consistent with reduced Aβ pathology, treatment of Picalm+/-; 5XFAD mice with artesunate improved CBF responses, BBB integrity and behavior on novel object location and recognition, burrowing and nesting. Endothelial-specific knockout of PICALM abolished all beneficial effects of artesunate in 5XFAD mice indicating that endothelial PICALM is required for its therapeutic effects. CONCLUSIONS Artesunate increases PICALM levels and Aβ clearance at the BBB which prevents development of Aβ pathology and functional deficits in mice and holds potential for translation to human AD.
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Affiliation(s)
- Kassandra Kisler
- Department of Physiology and Neuroscience and the Zilkha Neurogenetic Institute, Keck School of Medicine of the University of Southern California, 1501 San Pablo St, Los Angeles, CA 90089 USA
| | - Abhay P. Sagare
- Department of Physiology and Neuroscience and the Zilkha Neurogenetic Institute, Keck School of Medicine of the University of Southern California, 1501 San Pablo St, Los Angeles, CA 90089 USA
| | - Divna Lazic
- Department of Physiology and Neuroscience and the Zilkha Neurogenetic Institute, Keck School of Medicine of the University of Southern California, 1501 San Pablo St, Los Angeles, CA 90089 USA
| | - Sam Bazzi
- Department of Physiology and Neuroscience and the Zilkha Neurogenetic Institute, Keck School of Medicine of the University of Southern California, 1501 San Pablo St, Los Angeles, CA 90089 USA
| | - Erica Lawson
- Department of Physiology and Neuroscience and the Zilkha Neurogenetic Institute, Keck School of Medicine of the University of Southern California, 1501 San Pablo St, Los Angeles, CA 90089 USA
| | - Ching-Ju Hsu
- Department of Physiology and Neuroscience and the Zilkha Neurogenetic Institute, Keck School of Medicine of the University of Southern California, 1501 San Pablo St, Los Angeles, CA 90089 USA
| | - Yaoming Wang
- Department of Physiology and Neuroscience and the Zilkha Neurogenetic Institute, Keck School of Medicine of the University of Southern California, 1501 San Pablo St, Los Angeles, CA 90089 USA
| | - Anita Ramanathan
- Department of Physiology and Neuroscience and the Zilkha Neurogenetic Institute, Keck School of Medicine of the University of Southern California, 1501 San Pablo St, Los Angeles, CA 90089 USA
| | - Amy R. Nelson
- Department of Physiology and Neuroscience and the Zilkha Neurogenetic Institute, Keck School of Medicine of the University of Southern California, 1501 San Pablo St, Los Angeles, CA 90089 USA
| | - Zhen Zhao
- Department of Physiology and Neuroscience and the Zilkha Neurogenetic Institute, Keck School of Medicine of the University of Southern California, 1501 San Pablo St, Los Angeles, CA 90089 USA
| | - Berislav V. Zlokovic
- Department of Physiology and Neuroscience and the Zilkha Neurogenetic Institute, Keck School of Medicine of the University of Southern California, 1501 San Pablo St, Los Angeles, CA 90089 USA
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6
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Barisano G, Kisler K, Wilkinson B, Nikolakopoulou AM, Sagare AP, Wang Y, Gilliam W, Huuskonen MT, Hung ST, Ichida JK, Gao F, Coba MP, Zlokovic BV. A "multi-omics" analysis of blood-brain barrier and synaptic dysfunction in APOE4 mice. J Exp Med 2022; 219:e20221137. [PMID: 36040482 PMCID: PMC9435921 DOI: 10.1084/jem.20221137] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 08/02/2022] [Accepted: 08/04/2022] [Indexed: 02/02/2023] Open
Abstract
Apolipoprotein E4 (APOE4), the main susceptibility gene for Alzheimer's disease, leads to blood-brain barrier (BBB) breakdown in humans and mice. Remarkably, BBB dysfunction predicts cognitive decline and precedes synaptic deficits in APOE4 human carriers. How APOE4 affects BBB and synaptic function at a molecular level, however, remains elusive. Using single-nucleus RNA-sequencing and phosphoproteome and proteome analysis, we show that APOE4 compared with APOE3 leads to an early disruption of the BBB transcriptome in 2-3-mo-old APOE4 knock-in mice, followed by dysregulation in protein signaling networks controlling cell junctions, cytoskeleton, clathrin-mediated transport, and translation in brain endothelium, as well as transcription and RNA splicing suggestive of DNA damage in pericytes. Changes in BBB signaling mechanisms paralleled an early, progressive BBB breakdown and loss of pericytes, which preceded postsynaptic interactome disruption and behavioral deficits that developed 2-5 mo later. Thus, dysregulated signaling mechanisms in endothelium and pericytes in APOE4 mice reflect a molecular signature of a progressive BBB failure preceding changes in synaptic function and behavior.
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Affiliation(s)
- Giuseppe Barisano
- Department of Physiology and Neuroscience, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA
- Neuroscience Graduate Program, University of Southern California, Los Angeles, CA
| | - Kassandra Kisler
- Department of Physiology and Neuroscience, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA
| | - Brent Wilkinson
- Department of Physiology and Neuroscience, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA
| | - Angeliki Maria Nikolakopoulou
- Department of Physiology and Neuroscience, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA
| | - Abhay P. Sagare
- Department of Physiology and Neuroscience, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA
| | - Yaoming Wang
- Department of Physiology and Neuroscience, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA
| | - William Gilliam
- Department of Physiology and Neuroscience, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA
| | - Mikko T. Huuskonen
- Department of Physiology and Neuroscience, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA
| | - Shu-Ting Hung
- Department of Physiology and Neuroscience, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA
- Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA
- Eli and Edythe Broad CIRM Center for Regenerative Medicine and Stem Cell Research at University of Southern California, Los Angeles, CA
| | - Justin K. Ichida
- Department of Physiology and Neuroscience, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA
- Department of Stem Cell Biology and Regenerative Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA
- Eli and Edythe Broad CIRM Center for Regenerative Medicine and Stem Cell Research at University of Southern California, Los Angeles, CA
| | - Fan Gao
- Caltech Bioinformatics Resource Center, Caltech, Pasadena, CA
| | - Marcelo P. Coba
- Department of Physiology and Neuroscience, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA
| | - Berislav V. Zlokovic
- Department of Physiology and Neuroscience, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA
- Alzheimer’s Disease Research Center, Keck School of Medicine, University of Southern California, Los Angeles, CA
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7
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Li W, Zou J, Shang J, Gao C, Sun R, Liu R, Cao H, Wang Y, Zhang J. Both the Complexity of Tight Junctions and Endothelial Transcytosis Are Increased During BBB Postnatal Development in Rats. Front Neurosci 2022; 16:850857. [PMID: 35573303 PMCID: PMC9095945 DOI: 10.3389/fnins.2022.850857] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2022] [Accepted: 03/14/2022] [Indexed: 12/01/2022] Open
Abstract
The blood-brain barrier (BBB) comprises a single layer of endothelial cells and maintains a safe and homeostatic environment for proper neuronal function and synaptic transmission. BBB is not a discrete physical barrier, but a complex, dynamic, and adaptable interface. BBB continues to mature under the influence of the neural environment within a short period of time after birth. However, the basic mechanism of BBB formation and maintenance remains a mystery. Early studies have identified two structural characteristics of microvascular endothelium: special tight junctions (TJs) and a very low transcellular vesicle transport rate. Previous studies believed that BBB damage was mainly due to the destruction of tight junctions, and the role of vesicle transcytosis was neglected, so there was a lack of research on its impact on blood-brain barrier. It is urgent to get a better clarification of the unique structural and functional characteristics of the BBB endothelium to explain the role of BBB injury in neurological diseases. RNA sequencing was used to study the molecular characterization of cerebral cortex vascular endothelium by isolating them from neonatal, adolescent and adult rats. For investigation the maintenance mechanism of the BBB, we focused on the cellular and molecular regulation of barrier formation and the two characteristics of microvascular endothelial cells. Interestingly, we found that during the development of the blood-brain barrier, although the tight junctions gradually mature, endothelial cell transcytosis is gradually enhanced, resulting in an increase in the permeability of the blood-brain barrier. This study suggested that under physiological conditions, low vesicle transport is playing an important role in maintaining the integrity of the blood-brain barrier. This study not only summarized the unique characteristics of microvascular endothelial cells, but also illustrated a clarified mechanism of the development and maintenance of BBB which can provide new therapeutic opportunities for central nervous system drug delivery. Raw data of RNA sequencing were deposited in NCBI Sequence Read Archive database (PRJNA790676).
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Affiliation(s)
- Wei Li
- Department of Neurology, Zhengzhou University People’s Hospital, Henan Provincial People’s Hospital, Zhengzhou, China
| | - Jinlong Zou
- Department of Neurology, Henan University People’s Hospital, Henan Provincial People’s Hospital, Zhengzhou, China
| | - Junkui Shang
- Department of Neurology, Zhengzhou University People’s Hospital, Henan Provincial People’s Hospital, Zhengzhou, China
| | - Chenhao Gao
- Department of Neurology, Zhengzhou University People’s Hospital, Henan Provincial People’s Hospital, Zhengzhou, China
| | - Ruihua Sun
- Department of Neurology, Zhengzhou University People’s Hospital, Henan Provincial People’s Hospital, Zhengzhou, China
| | - Ruijie Liu
- Department of Neurology, Henan University People’s Hospital, Henan Provincial People’s Hospital, Zhengzhou, China
| | - Huixia Cao
- Department of Nephrology, Henan Provincial Key Laboratory of Kidney Disease and Immunology, Henan Provincial People’s Hospital, Zhengzhou University People’s Hospital, Henan University People’s Hospital, Zhengzhou, China
| | - Yanliang Wang
- Department of Nephrology, Henan Provincial Key Laboratory of Kidney Disease and Immunology, Henan Provincial People’s Hospital, Zhengzhou University People’s Hospital, Henan University People’s Hospital, Zhengzhou, China
| | - Jiewen Zhang
- Department of Neurology, Zhengzhou University People’s Hospital, Henan Provincial People’s Hospital, Zhengzhou, China
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8
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Machado-Pereira M, Saraiva C, Bernardino L, Cristóvão AC, Ferreira R. Argonaute-2 protects the neurovascular unit from damage caused by systemic inflammation. J Neuroinflammation 2022; 19:11. [PMID: 34991639 PMCID: PMC8740421 DOI: 10.1186/s12974-021-02324-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Accepted: 11/12/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The brain vasculature plays a pivotal role in the inflammatory process by modulating the interaction between blood cells and the neurovascular unit. Argonaute-2 (Ago2) has been suggested as essential for endothelial survival but its role in the brain vasculature or in the endothelial-glial crosstalk has not been addressed. Thus, our aim was to clarify the significance of Ago2 in the inflammatory responses elicited by these cell types. METHODS Mouse primary cultures of brain endothelial cells, astrocytes and microglia were used to evaluate cellular responses to the modulation of Ago2. Exposure of microglia to endothelial cell-conditioned media was used to assess the potential for in vivo studies. Adult mice were injected intraperitoneally with lipopolysaccharide (LPS) (2 mg/kg) followed by three daily intraperitoneal injections of Ago2 (0.4 nM) to assess markers of endothelial disruption, glial reactivity and neuronal function. RESULTS Herein, we demonstrated that LPS activation disturbed the integrity of adherens junctions and downregulated Ago2 in primary brain endothelial cells. Exogenous treatment recovered intracellular Ago2 above control levels and recuperated vascular endothelial-cadherin expression, while downregulating LPS-induced nitric oxide release. Primary astrocytes did not show a significant change in Ago2 levels or response to the modulation of the Ago2 system, although endogenous Ago2 was shown to be critical in the maintenance of tumor necrosis factor-α basal levels. LPS-activated primary microglia overexpressed Ago2, and Ago2 silencing contained the inflammatory response to some extent, preventing interleukin-6 and nitric oxide release. Moreover, the secretome of Ago2-modulated brain endothelial cells had a protective effect over microglia. The intraperitoneal injection of LPS impaired blood-brain barrier and neuronal function, while triggering inflammation, and the subsequent systemic administration of Ago2 reduced or normalized endothelial, glial and neuronal markers of LPS damage. This outcome likely resulted from the direct action of Ago2 over the brain endothelium, which reestablished glial and neuronal function. CONCLUSIONS Ago2 could be regarded as a putative therapeutic agent, or target, in the recuperation of the neurovascular unit in inflammatory conditions.
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Affiliation(s)
- Marta Machado-Pereira
- Health Sciences Research Centre (CICS-UBI), University of Beira Interior, Rua Marquês d’Ávila e Bolama, 6201-001 Covilhã, Portugal
| | - Cláudia Saraiva
- Health Sciences Research Centre (CICS-UBI), University of Beira Interior, Rua Marquês d’Ávila e Bolama, 6201-001 Covilhã, Portugal
- Present Address: Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, 7 Avenue des Hauts-Fourneaux, 4362 Esch-sur-Alzette, Luxembourg
| | - Liliana Bernardino
- Health Sciences Research Centre (CICS-UBI), University of Beira Interior, Rua Marquês d’Ávila e Bolama, 6201-001 Covilhã, Portugal
| | - Ana C. Cristóvão
- Health Sciences Research Centre (CICS-UBI), University of Beira Interior, Rua Marquês d’Ávila e Bolama, 6201-001 Covilhã, Portugal
- NeuroSoV, UBImedical, EM506, University of Beira Interior, Covilhã, Portugal
| | - Raquel Ferreira
- Health Sciences Research Centre (CICS-UBI), University of Beira Interior, Rua Marquês d’Ávila e Bolama, 6201-001 Covilhã, Portugal
- CEDOC, NOVA Medical School|Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, Campo dos Mártires da Pátria, 130, 1169-056 Lisboa, Portugal
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9
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mTOR Attenuation with Rapamycin Reverses Neurovascular Uncoupling and Memory Deficits in Mice Modeling Alzheimer's Disease. J Neurosci 2021; 41:4305-4320. [PMID: 33888602 DOI: 10.1523/jneurosci.2144-20.2021] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 02/19/2021] [Accepted: 03/02/2021] [Indexed: 02/07/2023] Open
Abstract
Vascular dysfunction is a universal feature of aging and decreased cerebral blood flow has been identified as an early event in the pathogenesis of Alzheimer's disease (AD). Cerebrovascular dysfunction in AD includes deficits in neurovascular coupling (NVC), a mechanism that ensures rapid delivery of energy substrates to active neurons through the blood supply. The mechanisms underlying NVC impairment in AD, however, are not well understood. We have previously shown that mechanistic/mammalian target of rapamycin (mTOR) drives cerebrovascular dysfunction in models of AD by reducing the activity of endothelial nitric oxide synthase (eNOS), and that attenuation of mTOR activity with rapamycin is sufficient to restore eNOS-dependent cerebrovascular function. Here we show mTOR drives NVC impairments in an AD model through the inhibition of neuronal NOS (nNOS)- and non-NOS-dependent components of NVC, and that mTOR attenuation with rapamycin is sufficient to restore NVC and even enhance it above WT responses. Restoration of NVC and concomitant reduction of cortical amyloid-β levels effectively treated memory deficits in 12-month-old hAPP(J20) mice. These data indicate that mTOR is a critical driver of NVC dysfunction and underlies cognitive impairment in an AD model. Together with our previous findings, the present studies suggest that mTOR promotes cerebrovascular dysfunction in AD, which is associated with early disruption of nNOS activation, through its broad negative impact on nNOS as well as on non-NOS components of NVC. Our studies highlight the potential of mTOR attenuation as an efficacious treatment for AD and potentially other neurologic diseases of aging.SIGNIFICANCE STATEMENT Failure of the blood flow response to neuronal activation [neurovascular coupling (NVC)] in a model of AD precedes the onset of AD-like cognitive symptoms and is driven, to a large extent, by mammalian/mechanistic target of rapamycin (mTOR)-dependent inhibition of nitric oxide synthase activity. Our studies show that mTOR also drives AD-like failure of non-nitric oxide (NO)-mediated components of NVC. Thus, mTOR attenuation may serve to treat AD, where we find that neuronal NO synthase is profoundly reduced early in disease progression, and potentially other neurologic diseases of aging with cerebrovascular dysfunction as part of their etiology.
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10
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Zhang Y, Qin Y, Chopp M, Li C, Kemper A, Liu X, Wang X, Zhang L, Zhang ZG. Ischemic Cerebral Endothelial Cell-Derived Exosomes Promote Axonal Growth. Stroke 2020; 51:3701-3712. [PMID: 33138691 PMCID: PMC7686085 DOI: 10.1161/strokeaha.120.031728] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
BACKGROUND AND PURPOSE Cerebral endothelial cells (CECs) and axons of neurons interact to maintain vascular and neuronal homeostasis and axonal remodeling in normal and ischemic brain, respectively. However, the role of exosomes in the interaction of CECs and axons in brain under normal conditions and after stroke is unknown. METHODS Exosomes were isolated from CECs of nonischemic rats and is chemic rats (nCEC-exos and isCEC-exos), respectively. A multicompartmental cell culture system was used to separate axons from neuronal cell bodies. RESULTS Axonal application of nCEC-exos promotes axonal growth of cortical neurons, whereas isCEC-exos further enhance axonal growth than nCEC-exos. Ultrastructural analysis revealed that CEC-exos applied into distal axons were internalized by axons and reached to their parent somata. Bioinformatic analysis revealed that both nCEC-exos and isCEC-exos contain abundant mature miRNAs; however, isCEC-exos exhibit more robust elevation of select miRNAs than nCEC-exos. Mechanistically, axonal application of nCEC-exos and isCEC-exos significantly elevated miRNAs and reduced proteins in distal axons and their parent somata that are involved in inhibiting axonal outgrowth. Blockage of axonal transport suppressed isCEC-exo-altered miRNAs and proteins in somata but not in distal axons. CONCLUSIONS nCEC-exos and isCEC-exos facilitate axonal growth by altering miRNAs and their target protein profiles in recipient neurons.
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Affiliation(s)
- Yi Zhang
- Department of Neurology, Henry Ford Hospital, Detroit, Michigan, 48202
| | - Yi Qin
- Department of Neurology, Henry Ford Hospital, Detroit, Michigan, 48202
| | - Michael Chopp
- Department of Neurology, Henry Ford Hospital, Detroit, Michigan, 48202
- Department of Physics, Oakland University, Rochester, Michigan, 48309
| | - Chao Li
- Department of Neurology, Henry Ford Hospital, Detroit, Michigan, 48202
| | - Amy Kemper
- Department of Pathology, Henry Ford Hospital, Detroit, Michigan, 48202
| | - Xianshuang Liu
- Department of Neurology, Henry Ford Hospital, Detroit, Michigan, 48202
| | - Xinli Wang
- Department of Neurology, Henry Ford Hospital, Detroit, Michigan, 48202
| | - Li Zhang
- Department of Neurology, Henry Ford Hospital, Detroit, Michigan, 48202
| | - Zheng Gang Zhang
- Department of Neurology, Henry Ford Hospital, Detroit, Michigan, 48202
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11
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Francisco DMF, Marchetti L, Rodríguez-Lorenzo S, Frías-Anaya E, Figueiredo RM, Winter P, Romero IA, de Vries HE, Engelhardt B, Bruggmann R. Advancing brain barriers RNA sequencing: guidelines from experimental design to publication. Fluids Barriers CNS 2020; 17:51. [PMID: 32811511 PMCID: PMC7433166 DOI: 10.1186/s12987-020-00207-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Accepted: 07/06/2020] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND RNA sequencing (RNA-Seq) in its varied forms has become an indispensable tool for analyzing differential gene expression and thus characterization of specific tissues. Aiming to understand the brain barriers genetic signature, RNA seq has also been introduced in brain barriers research. This has led to availability of both, bulk and single-cell RNA-Seq datasets over the last few years. If appropriately performed, the RNA-Seq studies provide powerful datasets that allow for significant deepening of knowledge on the molecular mechanisms that establish the brain barriers. However, RNA-Seq studies comprise complex workflows that require to consider many options and variables before, during and after the proper sequencing process. MAIN BODY In the current manuscript, we build on the interdisciplinary experience of the European PhD Training Network BtRAIN ( https://www.btrain-2020.eu/ ) where bioinformaticians and brain barriers researchers collaborated to analyze and establish RNA-Seq datasets on vertebrate brain barriers. The obstacles BtRAIN has identified in this process have been integrated into the present manuscript. It provides guidelines along the entire workflow of brain barriers RNA-Seq studies starting from the overall experimental design to interpretation of results. Focusing on the vertebrate endothelial blood-brain barrier (BBB) and epithelial blood-cerebrospinal-fluid barrier (BCSFB) of the choroid plexus, we provide a step-by-step description of the workflow, highlighting the decisions to be made at each step of the workflow and explaining the strengths and weaknesses of individual choices made. Finally, we propose recommendations for accurate data interpretation and on the information to be included into a publication to ensure appropriate accessibility of the data and reproducibility of the observations by the scientific community. CONCLUSION Next generation transcriptomic profiling of the brain barriers provides a novel resource for understanding the development, function and pathology of these barrier cells, which is essential for understanding CNS homeostasis and disease. Continuous advancement and sophistication of RNA-Seq will require interdisciplinary approaches between brain barrier researchers and bioinformaticians as successfully performed in BtRAIN. The present guidelines are built on the BtRAIN interdisciplinary experience and aim to facilitate collaboration of brain barriers researchers with bioinformaticians to advance RNA-Seq study design in the brain barriers community.
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Affiliation(s)
- David M F Francisco
- Interfaculty Bioinformatics Unit and Swiss Institute of Bioinformatics, University of Bern, Bern, Switzerland
| | - Luca Marchetti
- Theodor Kocher Institute, University of Bern, Bern, Switzerland
| | - Sabela Rodríguez-Lorenzo
- MS Center Amsterdam, Amsterdam Neuroscience, Department of Molecular Cell Biology and Immunology, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Eduardo Frías-Anaya
- School of Life, Health and Chemical Sciences, The Open University, Milton Keynes, UK
| | - Ricardo M Figueiredo
- GenXPro GmbH, Frankfurt/Main, Germany
- Johann Wolfgang Goethe University, Frankfurt/Main, Germany
| | | | - Ignacio Andres Romero
- School of Life, Health and Chemical Sciences, The Open University, Milton Keynes, UK
| | - Helga E de Vries
- MS Center Amsterdam, Amsterdam Neuroscience, Department of Molecular Cell Biology and Immunology, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | | | - Rémy Bruggmann
- Interfaculty Bioinformatics Unit and Swiss Institute of Bioinformatics, University of Bern, Bern, Switzerland.
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12
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Lee YK, Uchida H, Smith H, Ito A, Sanchez T. The isolation and molecular characterization of cerebral microvessels. Nat Protoc 2019; 14:3059-3081. [PMID: 31586162 DOI: 10.1038/s41596-019-0212-0] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2017] [Accepted: 06/17/2019] [Indexed: 11/09/2022]
Abstract
The study of cerebral microvessels is becoming increasingly important in a wide variety of conditions, such as stroke, sepsis, traumatic brain injury and neurodegenerative diseases. However, the molecular mechanisms underlying cerebral microvascular dysfunction in these conditions are largely unknown. The molecular characterization of cerebral microvessels in experimental disease models has been hindered by the lack of a standardized method to reproducibly isolate intact cerebral microvessels with consistent cellular compositions and without the use of enzymatic digestion, which causes undesirable molecular and metabolic changes. Herein, we describe an optimized protocol for microvessel isolation from mouse brain cortex that yields microvessel fragments with consistent populations of discrete blood-brain barrier (BBB) components (endothelial cells, pericytes and astrocyte end feet) while retaining high RNA integrity and protein post-translational modifications (e.g., phosphorylation). We demonstrate that this protocol allows the quantification of changes in gene expression in a disease model (stroke) and the activation of signaling pathways in mice subjected to drug administration in vivo. We also describe the isolation of genomic DNA (gDNA) and bisulfite treatment for the assessment of DNA methylation, as well as the optimization of chromatin extraction and shearing from cortical microvessels. This optimized protocol and the described applications should improve the understanding of the molecular mechanisms governing cerebral microvascular dysfunction, which may help in the development of novel therapies for stroke and other neurologic conditions.
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Affiliation(s)
- Yun-Kyoung Lee
- Department of Pathology and Laboratory Medicine, Center for Vascular Biology, Weill Cornell Medicine, New York, NY, USA
| | - Hiroki Uchida
- Department of Pathology and Laboratory Medicine, Center for Vascular Biology, Weill Cornell Medicine, New York, NY, USA
| | - Helen Smith
- Department of Pathology and Laboratory Medicine, Center for Vascular Biology, Weill Cornell Medicine, New York, NY, USA
| | - Akira Ito
- Department of Pathology and Laboratory Medicine, Center for Vascular Biology, Weill Cornell Medicine, New York, NY, USA
| | - Teresa Sanchez
- Department of Pathology and Laboratory Medicine, Center for Vascular Biology, Weill Cornell Medicine, New York, NY, USA. .,Department of Neuroscience, Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA.
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13
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Chen Y, Wang L, Zhang Y, Zhou Y, Wei W, Wan Z. The Effect of Therapeutic Mild Hypothermia on Brain Microvascular Endothelial Cells During Ischemia-Reperfusion Injury. Neurocrit Care 2019; 28:379-387. [PMID: 29327153 DOI: 10.1007/s12028-017-0486-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND To determine the cerebral protective effects of mild hypothermia (MH) on cerebral microcirculation. METHODS We established ischemia-reperfusion (I/R) injury and MH treatment models with rat brain microvascular endothelial cells (RBMECs) in vitro and examined the apoptotic changes. The cultured RBMECs were randomly divided into the control group, I/R group, and MH group, which was further divided into two subgroups: intra-ischemia hypothermia (IIH) and post-ischemia hypothermia (PIH). Cell morphological changes were assessed using fluorescence microscopy. Apoptotic rates were obtained by flow cytometry. Expressions of caspase-3, Bax, and Bcl-2 were analyzed by Western blot. RESULTS I/R injury in vitro induced apoptosis of RBMECs. The apoptotic rates in the control group, I/R group, and MH group were 0.13, 19.04, and 13.13%, respectively (P < 0.01). Compared with the I/R group, the MH group showed a significant decrease in the number of apoptotic cells, mainly in stage I apoptotic cells (P < 0.0083). The caspase-3 and Bax expressions were significantly enhanced (P < 0.05) in RBMECs after I/R injury, while substantial decreases in Bcl-2 expression were noted (P < 0.05). Following MH intervention, the increase in caspase-3 and Bax expression was suppressed (P < 0.05), while Bcl-2 expression significantly increased. The apoptotic rates or protein expressions between the two subgroups were not different significantly (P > 0.05). CONCLUSIONS These results indicate that MH could inhibit RBMEC apoptosis by preventing pro-apoptotic cells and early apoptotic cells from progressing to intermediate and advanced stages. This may be due to the effect of MH on I/R-induced apoptotic gene expression changes.
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Affiliation(s)
- Yao Chen
- Department of Emergency Medicine, West China Hospital, Sichuan University, 37 Guoxue Road, Chengdu, 610041, Sichuan, China
| | - Lin Wang
- Department of Cardiology, Chengdu Shangjin Jin Nanfu Hospital, Chengdu, China
| | - Yun Zhang
- Department of Emergency, Wuxi People's Hospital, NanJing Medical University, Wuxi, China
| | - Yaxiong Zhou
- Department of Emergency Medicine, West China Hospital, Sichuan University, 37 Guoxue Road, Chengdu, 610041, Sichuan, China
| | - Wei Wei
- Department of Emergency Medicine, West China Hospital, Sichuan University, 37 Guoxue Road, Chengdu, 610041, Sichuan, China
| | - Zhi Wan
- Department of Emergency Medicine, West China Hospital, Sichuan University, 37 Guoxue Road, Chengdu, 610041, Sichuan, China.
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14
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Cao Y, Li Z, Ma L, Yang N, Guo X. Isoflurane-Induced Postoperative Neurovascular and Cognitive Dysfunction Is Associated with VEGF Overexpression in Aged Rats. J Mol Neurosci 2019; 69:215-223. [PMID: 31250275 DOI: 10.1007/s12031-019-01350-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Accepted: 05/29/2019] [Indexed: 12/18/2022]
Abstract
Postoperative cognitive dysfunction (POCD) is a common complication in older adults; however, its aetiology remains unclear. Although vascular endothelial growth factor (VEGF) is associated with blood-brain barrier (BBB) disorders and neurological disease, its role in POCD is unknown. Here, we investigated the effect of brain VEGF inhibition on isoflurane-induced cognitive impairment in an aged rat model of POCD. VEGF protein expression was increased in the hippocampus after isoflurane exposure, suggesting that inhalation anaesthesia induces hippocampal VEGF protein overexpression in aged rats. Pretreatment with 2 mg/kg RB-222, an anti-VEGF neutralizing antibody, may partially abolish the degradation of occludin protein in cerebral capillaries, thereby maintaining the ultrastructural and functional integrity of the hippocampal BBB. Inhibition of VEGF also significantly attenuated the isoflurane-induced cognitive deficits in the Morris water maze task. Together, our findings show, for the first time, that elevated expression of brain VEGF after isoflurane exposure contributes to POCD in aged rats. Therefore, therapeutic strategies involving VEGF should take into consideration its role in the pathogenesis of POCD.
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Affiliation(s)
- Yiyun Cao
- Department of Anesthesiology, Shanghai Sixth People's Hospital East Affiliated to Shanghai University of Medicine & Health Sciences, Shanghai, 200233, China.,Department of Anesthesiology, Peking University Third Hospital, Beijing, 100191, China
| | - Zhengqian Li
- Department of Anesthesiology, Peking University Third Hospital, Beijing, 100191, China
| | - Lijun Ma
- Department of Medical Imaging, North Minzu University, Yinchuan, 750021, Ningxia, China
| | - Ning Yang
- Department of Anesthesiology, Peking University Third Hospital, Beijing, 100191, China
| | - Xiangyang Guo
- Department of Anesthesiology, Peking University Third Hospital, Beijing, 100191, China.
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15
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Pericyte loss leads to circulatory failure and pleiotrophin depletion causing neuron loss. Nat Neurosci 2019; 22:1089-1098. [PMID: 31235908 PMCID: PMC6668719 DOI: 10.1038/s41593-019-0434-z] [Citation(s) in RCA: 210] [Impact Index Per Article: 42.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 05/22/2019] [Indexed: 12/11/2022]
Abstract
Pericytes are positioned between brain capillary endothelial cells, astrocytes and neurons. They degenerate in multiple neurological disorders. However, their role in the pathogenesis of these disorders remains debatable. Here we generate an inducible pericyte-specific Cre line and cross pericyte-specific Cre mice with iDTR mice carrying Cre-dependent human diphtheria toxin receptor. After pericyte ablation with diphtheria toxin, mice showed acute blood-brain barrier breakdown, severe loss of blood flow, and a rapid neuron loss that was associated with loss of pericyte-derived pleiotrophin (PTN), a neurotrophic growth factor. Intracerebroventricular PTN infusions prevented neuron loss in pericyte-ablated mice despite persistent circulatory changes. Silencing of pericyte-derived Ptn rendered neurons vulnerable to ischemic and excitotoxic injury. Our data demonstrate a rapid neurodegeneration cascade that links pericyte loss to acute circulatory collapse and loss of PTN neurotrophic support. These findings may have implications for the pathogenesis and treatment of neurological disorders that are associated with pericyte loss and/or neurovascular dysfunction.
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16
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Lin Y, Li L, Liu J, Zhao X, Ye J, Reinach PS, Qu J, Yan D. SIRT1 Deletion Impairs Retinal Endothelial Cell Migration Through Downregulation of VEGF-A/VEGFR-2 and MMP14. Invest Ophthalmol Vis Sci 2019; 59:5431-5440. [PMID: 30452596 DOI: 10.1167/iovs.17-23558] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Silent information regulator protein 1 (SIRT1) is a nicotinamide adenine dinucleotide-dependent deacetylase that is abundantly expressed in vascular endothelial cells (VECs), and it has an essential role in angiogenesis. However, its contribution to retinal vascular development remains unclear. Here we characterize its involvement in regulating this process under both physiological and pathologic conditions. Methods Endothelium-specific Sirt1 knockout mice were established using the Cre-lox system. VECs were isolated using magnetic beads and identified by immunostaining. Retinal whole-mount staining analyzed the retinal vascular patterns. SIRT1 was knocked down or overexpressed in human retinal microvascular endothelial cells (HRMECs) using small interfering RNA (siRNA) or lentivirus infection, respectively. Scratch assay, Transwell, and Matrigel angiogenesis assay evaluated cell migration and tube formation, respectively. Quantitative RT-PCR analyzed genes regulating VEC migration. Western blotting determined protein expression. Coimmunoprecipitation detected the interaction of hypoxia-inducible factor 1α (HIF-1α) and SIRT1 as well as acetylation status of HIF-1α. Results Specific deletion of Sirt1 in VECs dramatically delayed retinal vessel expansion and reduced vessel density. In the oxygen-induced retinopathy (OIR) mouse model, Sirt1 ablation markedly suppressed retinal revascularization and consequently increased retinal avascularity. SIRT1 downregulation in HRMECs inhibited cell migration and tube formation, while overexpression of SIRT1 had the opposite effects. Vascular endothelial growth factor-A (VEGF-A)/VEGF receptor-2 (VEGFR-2), and matrix metalloproteinases 14 (MMP14) expression significantly declined in Sirt1-null VECs, as well as SIRT1 siRNA-transfected HRMECs. SIRT1 downregulation upregulated the HIF-1α acetylation status. Conversely, SIRT1 overexpression decreased this response. Conclusions SIRT1 contributes to both physiological and pathologic retinal angiogenesis through promoting retinal VEC migration. Its underlying molecular mechanism involves SIRT1-mediated deacetylation of HIF-1α and subsequent upregulation of VEGF-A/VEGFR-2 and MMP14 expression.
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Affiliation(s)
- Yong Lin
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China.,State Key Laboratory of Ophthalmology, Optometry and Visual Science, Wenzhou, Zhejiang, China
| | - Li Li
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China.,State Key Laboratory of Ophthalmology, Optometry and Visual Science, Wenzhou, Zhejiang, China
| | - Junjie Liu
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China.,State Key Laboratory of Ophthalmology, Optometry and Visual Science, Wenzhou, Zhejiang, China
| | - Xiaoting Zhao
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China.,State Key Laboratory of Ophthalmology, Optometry and Visual Science, Wenzhou, Zhejiang, China
| | - Juxiu Ye
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China.,State Key Laboratory of Ophthalmology, Optometry and Visual Science, Wenzhou, Zhejiang, China
| | - Peter S Reinach
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China.,State Key Laboratory of Ophthalmology, Optometry and Visual Science, Wenzhou, Zhejiang, China
| | - Jia Qu
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China.,State Key Laboratory of Ophthalmology, Optometry and Visual Science, Wenzhou, Zhejiang, China
| | - Dongsheng Yan
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China.,State Key Laboratory of Ophthalmology, Optometry and Visual Science, Wenzhou, Zhejiang, China
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17
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Yu H, Wang L, Zhang H, Wei W, Chen Y, Tang W, Wan Z. Effect of mild hypothermia on cerebral microcirculation in a murine cardiopulmonary resuscitation model. Microcirculation 2019; 26:e12537. [PMID: 30801897 DOI: 10.1111/micc.12537] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2018] [Revised: 02/10/2019] [Accepted: 02/20/2019] [Indexed: 02/05/2023]
Abstract
BACKGROUND We hypothesized that mild hypothermia may improve brain microcirculation by reducing cerebral microvascular endothelial cells apoptosis, and this effect may be maximized by moving up the initiation of mild hypothermia from after return of spontaneous circulation (ROSC) to the start of cardiopulmonary resuscitation (CPR). METHODS A total of 35 rats were randomized into the intra-arrest hypothermia group (IAH), post-resuscitation hypothermia group (PRH), normothermia group (NT), or the sham control group. A craniotomy exposed the parietal cortex for visualization of microcirculation. Ventricular fibrillation was electrically induced and untreated for 8 minutes, followed by 8 minutes of precordial compression and mechanical ventilation. Hypothermia (33 ± 0.5°C) in the IAH and PRH group was induced and maintained for 6 hours at the beginning of CPR or after ROSC, respectively. At baseline, 1, 3, and 6 hours, hemodynamic parameters were measured and the pial microcirculations were visualized with a sidestream dark field imaging video microscope. Microvascular flow index and perfused microvessel density (PMD) were calculated. Rats were euthanized, and brain tissues were removed at 3 and 6 hours separately. Expression of Bax, Bcl-2, and Caspase 3 in brain microvascular endothelial cells was examined by Western blot. RESULTS Microvascular flow index and PMD were significantly reduced after cardiac arrest and resuscitation (all P < 0.05), and the former was largely preserved by hypothermia regardless when the hypothermia treatment was induced (P < 0.05). Bax and Caspase 3 increased and Bcl-2 decreased significantly after resuscitation, and hypothermia treatment reversed the trend partly (all P < 0.05). A moderate correlation was observed between MFI and those proteins (Bcl-2/BAX: 3 hours: r = 0.730, P = 0.002; 6 hours: r = 0.743, P = 0.002). CONCLUSION Mild hypothermia improves cerebral microcirculatory blood supply, partly by inhibiting endothelial cell apoptosis. Mild hypothermia induced simultaneously with CPR has shown no additional benefit in microcirculation or endothelial cell apoptosis.
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Affiliation(s)
- Haifang Yu
- Department of Emergency Medicine, West China Hospital, Sichuan University, Chengdu, China.,Weil Institute of Emergency and Critical Care Medicine, Richmond, Virginia
| | - Lin Wang
- Department of Cardiology, Chengdu ShangjinNanfu Hospital, Chengdu, China
| | - Haihong Zhang
- Department of Emergency Medicine, West China Hospital, Sichuan University, Chengdu, China
| | - Wei Wei
- Department of Emergency Medicine, West China Hospital, Sichuan University, Chengdu, China
| | - Yao Chen
- Department of Emergency Medicine, West China Hospital, Sichuan University, Chengdu, China
| | - Wanchun Tang
- Weil Institute of Emergency and Critical Care Medicine, Richmond, Virginia
| | - Zhi Wan
- Department of Emergency Medicine, West China Hospital, Sichuan University, Chengdu, China
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Endothelial Adora2a Activation Promotes Blood-Brain Barrier Breakdown and Cognitive Impairment in Mice with Diet-Induced Insulin Resistance. J Neurosci 2019; 39:4179-4192. [PMID: 30886019 DOI: 10.1523/jneurosci.2506-18.2019] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 02/18/2019] [Accepted: 03/06/2019] [Indexed: 02/07/2023] Open
Abstract
Obesity and insulin resistance elicit blood-brain barrier (BBB) breakdown in humans and animal models, but the relative contributions of the two pathologies remain poorly understood. These studies initially addressed the temporal progression of cerebrovascular dysfunction relative to dietary obesity or diet-induced insulin resistance in male mice. Obesity increased BBB permeability to the low molecular weight fluorophore sodium fluorescein (NaFl), whereas diet-induced insulin resistance increased permeability to both NaFl and Evans blue, which forms a high molecular weight complex with serum albumin. Serial section transmission electron microscopy analysis of hippocampal capillaries revealed that diabetes promotes involution of tight junctions, fenestration of endothelial cells, and pericyte regression. Chronic activation of adenosine receptor 2a (Adora2a) erodes tight junctions between endothelial cells of the cerebral vasculature in other models of chronic neuropathology, and we observed that acute Adora2a antagonism normalized BBB permeability in wild-type mice with diet-induced insulin resistance. Experiments in mice with inducible deletion of Adora2a in endothelial cells revealed protection against BBB breakdown with diet-induced insulin resistance, despite comparable metabolic dysfunction relative to nontransgenic littermates. Protection against BBB breakdown was associated with decreased vascular inflammation, recovery of hippocampal synaptic plasticity, and restoration of hippocampus-dependent memory. These findings indicate that Adora2a-mediated signaling in vascular endothelial cells disrupts the BBB in dietary obesity, and implicate cerebrovascular dysfunction as the underlying mechanism for deficits in synaptic plasticity and cognition with obesity and insulin resistance.SIGNIFICANCE STATEMENT The blood-brain barrier (BBB) restricts the entry of circulating factors into the brain, but obesity promotes BBB breakdown in humans and animal models. We used transgenic mice with resistance to BBB breakdown to investigate the role of neurovascular dysfunction in high-fat diet (HFD)-induced cognitive impairment. Transgenic mice with inducible ablation of Adora2a in endothelial cells were protected against BBB breakdown on HFD, despite comparable metabolic impairments relative to normal mice. Transgenic mice were also resistant to HFD-induced cognitive dysfunction and were protected against deficits in hippocampal synaptic plasticity. These findings indicate that Adora2a-mediated signaling in endothelial cells mediates obesity-induced BBB breakdown, and implicate cerebrovascular dysfunction as the mechanism for deficits in synaptic plasticity and cognition with obesity and diabetes.
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Ma Q, Zhao Z, Sagare AP, Wu Y, Wang M, Owens NC, Verghese PB, Herz J, Holtzman DM, Zlokovic BV. Blood-brain barrier-associated pericytes internalize and clear aggregated amyloid-β42 by LRP1-dependent apolipoprotein E isoform-specific mechanism. Mol Neurodegener 2018; 13:57. [PMID: 30340601 PMCID: PMC6194676 DOI: 10.1186/s13024-018-0286-0] [Citation(s) in RCA: 165] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Accepted: 10/01/2018] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Clearance at the blood-brain barrier (BBB) plays an important role in removal of Alzheimer's amyloid-β (Aβ) toxin from brain both in humans and animal models. Apolipoprotein E (apoE), the major genetic risk factor for AD, disrupts Aβ clearance at the BBB. The cellular and molecular mechanisms, however, still remain unclear, particularly whether the BBB-associated brain capillary pericytes can contribute to removal of aggregated Aβ from brain capillaries, and whether removal of Aβ aggregates by pericytes requires apoE, and if so, is Aβ clearance on pericytes apoE isoform-specific. METHODS We performed immunostaining for Aβ and pericyte biomarkers on brain capillaries (< 6 μm in diameter) on tissue sections derived from AD patients and age-matched controls, and APPSwe/0 mice and littermate controls. Human Cy3-Aβ42 uptake by pericytes was studied on freshly isolated brain slices from control mice, pericyte LRP1-deficient mice (Lrplox/lox;Cspg4-Cre) and littermate controls. Clearance of aggregated Aβ42 by mouse pericytes was studied on multi-spot glass slides under different experimental conditions including pharmacologic and/or genetic inhibition of the low density lipoprotein receptor related protein 1 (LRP1), an apoE receptor, and/or silencing mouse endogenous Apoe in the presence and absence of human astrocyte-derived lipidated apoE3 or apoE4. Student's t-test and one-way ANOVA followed by Bonferroni's post-hoc test were used for statistical analysis. RESULTS First, we found that 35% and 60% of brain capillary pericytes accumulate Aβ in AD patients and 8.5-month-old APPSw/0 mice, respectively, compared to negligible uptake in controls. Cy3-Aβ42 species were abundantly taken up by pericytes on cultured mouse brain slices via LRP1, as shown by both pharmacologic and genetic inhibition of LRP1 in pericytes. Mouse pericytes vigorously cleared aggregated Cy3-Aβ42 from multi-spot glass slides via LRP1, which was inhibited by pharmacologic and/or genetic knockdown of mouse endogenous apoE. Human astrocyte-derived lipidated apoE3, but not apoE4, normalized Aβ42 clearance by mouse pericytes with silenced mouse apoE. CONCLUSIONS Our data suggest that BBB-associated pericytes clear Aβ aggregates via an LRP1/apoE isoform-specific mechanism. These data support the role of LRP1/apoE interactions on pericytes as a potential therapeutic target for controlling Aβ clearance in AD.
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Affiliation(s)
- Qingyi Ma
- Center for Neurodegeneration and Regeneration, Zilkha Neurogenetic Institute and Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, California 90033 USA
- Lawrence D. Longo, MD Center for Neonatal Biology, Division of Pharmacology, Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, CA 92350 USA
| | - Zhen Zhao
- Center for Neurodegeneration and Regeneration, Zilkha Neurogenetic Institute and Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, California 90033 USA
| | - Abhay P Sagare
- Center for Neurodegeneration and Regeneration, Zilkha Neurogenetic Institute and Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, California 90033 USA
| | - Yingxi Wu
- Center for Neurodegeneration and Regeneration, Zilkha Neurogenetic Institute and Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, California 90033 USA
| | - Min Wang
- Center for Neurodegeneration and Regeneration, Zilkha Neurogenetic Institute and Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, California 90033 USA
| | - Nelly Chuqui Owens
- Center for Neurodegeneration and Regeneration, Zilkha Neurogenetic Institute and Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, California 90033 USA
| | | | - Joachim Herz
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX USA
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX USA
- Department of Neurology and Neurotherapeutics and Center for Translational Neurodegeneration Research, University of Texas Southwestern Medical Center, Dallas, TX USA
| | - David M Holtzman
- Department of Neurology, Hope Center for Neurological Disorders, Knight Alzheimer’s Disease Research Center, Washington University School of Medicine, Saint Louis, MO 63110 USA
| | - Berislav V Zlokovic
- Center for Neurodegeneration and Regeneration, Zilkha Neurogenetic Institute and Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, California 90033 USA
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20
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Van Skike CE, Jahrling JB, Olson AB, Sayre NL, Hussong SA, Ungvari Z, Lechleiter JD, Galvan V. Inhibition of mTOR protects the blood-brain barrier in models of Alzheimer's disease and vascular cognitive impairment. Am J Physiol Heart Circ Physiol 2018; 314:H693-H703. [PMID: 29351469 PMCID: PMC5966773 DOI: 10.1152/ajpheart.00570.2017] [Citation(s) in RCA: 86] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Revised: 11/29/2017] [Accepted: 12/13/2017] [Indexed: 01/05/2023]
Abstract
An intact blood-brain barrier (BBB) limits entry of proinflammatory and neurotoxic blood-derived factors into the brain parenchyma. The BBB is damaged in Alzheimer's disease (AD), which contributes significantly to the progression of AD pathologies and cognitive decline. However, the mechanisms underlying BBB breakdown in AD remain elusive, and no interventions are available for treatment or prevention. We and others recently established that inhibition of the mammalian/mechanistic target of rapamycin (mTOR) pathway with rapamycin yields significant neuroprotective effects, improving cerebrovascular and cognitive function in mouse models of AD. To test whether mTOR inhibition protects the BBB in neurological diseases of aging, we treated hAPP(J20) mice modeling AD and low-density lipoprotein receptor-null (LDLR-/-) mice modeling vascular cognitive impairment with rapamycin. We found that inhibition of mTOR abrogates BBB breakdown in hAPP(J20) and LDLR-/- mice. Experiments using an in vitro BBB model indicated that mTOR attenuation preserves BBB integrity through upregulation of specific tight junction proteins and downregulation of matrix metalloproteinase-9 activity. Together, our data establish mTOR activity as a critical mediator of BBB breakdown in AD and, potentially, vascular cognitive impairment and suggest that rapamycin and/or rapalogs could be used for the restoration of BBB integrity. NEW & NOTEWORTHY This report establishes mammalian/mechanistic target of rapamycin as a critical mediator of blood-brain barrier breakdown in models of Alzheimer's disease and vascular cognitive impairment and suggests that drugs targeting the target of rapamycin pathway could be used for the restoration of blood-brain barrier integrity in disease states.
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MESH Headings
- Alzheimer Disease/drug therapy
- Alzheimer Disease/enzymology
- Alzheimer Disease/pathology
- Alzheimer Disease/psychology
- Animals
- Behavior, Animal
- Blood-Brain Barrier/drug effects
- Blood-Brain Barrier/enzymology
- Blood-Brain Barrier/pathology
- Cell Line
- Cognition
- Dementia, Vascular/drug therapy
- Dementia, Vascular/enzymology
- Dementia, Vascular/pathology
- Dementia, Vascular/psychology
- Disease Models, Animal
- Female
- Male
- Matrix Metalloproteinase 9/metabolism
- Mechanistic Target of Rapamycin Complex 1/metabolism
- Mice, Inbred C57BL
- Mice, Knockout
- Protein Kinase Inhibitors/pharmacology
- Receptors, LDL/deficiency
- Receptors, LDL/genetics
- Sirolimus/pharmacology
- TOR Serine-Threonine Kinases/antagonists & inhibitors
- TOR Serine-Threonine Kinases/metabolism
- Tight Junction Proteins/metabolism
- Tight Junctions/drug effects
- Tight Junctions/enzymology
- Tight Junctions/pathology
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Affiliation(s)
- Candice E Van Skike
- Department of Cellular and Integrative Physiology and Barshop Institute for Longevity and Aging Studies, University of Texas Health San Antonio , San Antonio, Texas
| | - Jordan B Jahrling
- Department of Cellular and Integrative Physiology and Barshop Institute for Longevity and Aging Studies, University of Texas Health San Antonio , San Antonio, Texas
| | - Angela B Olson
- Department of Cellular and Integrative Physiology and Barshop Institute for Longevity and Aging Studies, University of Texas Health San Antonio , San Antonio, Texas
| | - Naomi L Sayre
- Department of Neurosurgery, University of Texas Health San Antonio , San Antonio, Texas
- Department of Veterans Affairs, South Texas Veterans Health Care System, San Antonio, Texas
| | - Stacy A Hussong
- Department of Cellular and Integrative Physiology and Barshop Institute for Longevity and Aging Studies, University of Texas Health San Antonio , San Antonio, Texas
- Department of Veterans Affairs, South Texas Veterans Health Care System, San Antonio, Texas
| | - Zoltan Ungvari
- Department of Geriatric Medicine and Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center , Oklahoma City, Oklahoma
| | - James D Lechleiter
- Department of Cellular and Structural Biology, South Texas Research Facility Neuroscience Center, University of Texas Health San Antonio, San Antonio, Texas
| | - Veronica Galvan
- Department of Cellular and Integrative Physiology and Barshop Institute for Longevity and Aging Studies, University of Texas Health San Antonio , San Antonio, Texas
- Department of Veterans Affairs, South Texas Veterans Health Care System, San Antonio, Texas
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21
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Crouch EE, Doetsch F. FACS isolation of endothelial cells and pericytes from mouse brain microregions. Nat Protoc 2018; 13:738-751. [PMID: 29565899 DOI: 10.1038/nprot.2017.158] [Citation(s) in RCA: 80] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The vasculature is emerging as a key contributor to brain function during neurodevelopment and in mature physiological and pathological states. The brain vasculature itself also exhibits regional heterogeneity, highlighting the need to develop approaches for purifying cells from different microregions. Previous approaches for isolation of endothelial cells and pericytes have predominantly required transgenic mice and large amounts of tissue, and have resulted in impure populations. In addition, the prospective purification of brain pericytes has been complicated by the fact that widely used pericyte markers are also expressed by other cell types in the brain. Here, we describe the detailed procedures for simultaneous isolation of pure populations of endothelial cells and pericytes directly from adult mouse brain microregions using fluorescence-activated cell sorting (FACS) with antibodies against CD31 (endothelial cells) and CD13 (pericytes). This protocol is scalable and takes ∼5 h, including microdissection of the region of interest, enzymatic tissue dissociation, immunostaining, and FACS. This protocol allows the isolation of brain vascular cells from any mouse strain under diverse conditions; these cells can be used for multiple downstream applications, including in vitro and in vivo experiments, and transcriptomic, proteomic, metabolomic, epigenomic, and single-cell analysis.
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Affiliation(s)
- Elizabeth E Crouch
- Department of Pediatrics, University of California, San Francisco, San Francisco, California, USA
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22
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Ma Q, Zhang L. C-type natriuretic peptide functions as an innate neuroprotectant in neonatal hypoxic-ischemic brain injury in mouse via natriuretic peptide receptor 2. Exp Neurol 2018; 304:58-66. [PMID: 29501420 DOI: 10.1016/j.expneurol.2018.02.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2017] [Revised: 02/22/2018] [Accepted: 02/27/2018] [Indexed: 12/22/2022]
Abstract
Neonatal hypoxia-ischemia (HI) is the most common cause of brain injury in neonates, which leads to high neonatal mortality and severe neurological morbidity in later life (Vannucci, 2000; Volpe, 2001). Yet the molecular mechanisms of neuronal death and brain damage induced by neonatal HI remain largely elusive. Herein, using both in vivo and in vitro models, we determine an endogenous neuroprotectant role of c-type natriuretic peptide (CNP) in preserving neuronal survival after HI brain injury in mouse pups. Postnatal day 7 (P7) mouse pups with CNP deficiency (Nppclbab/lbab) exhibit increased brain infarct size and worsened long-term locomotor function after neonatal HI compared with wildtype control (Nppc+/+). In isolated primary cortical neurons, recombinant CNP dose-dependently protects primary neurons from oxygen-glucose deprivation (OGD) insult. This neuroprotective effect appears to be mediated through its cognate natriuretic peptide receptor 2 (NPR2), in that antagonization of NPR2, but not NPR3, exacerbates neuronal death and counteracts the protective effect of CNP on primary neurons exposed to OGD insult. Immunoblot and confocal microscopy demonstrate the abundant expression of NPR2 in neurons of the neonatal brain and in isolated primary cortical neurons as well. Moreover, similar to CNP deficiency, administration of NPR2 antagonist P19 via intracerebroventricular injection prior to HI results in exacerbated neuronal death and brain injury after HI. Altogether, the present study indicates that CNP and its cognate receptor NPR2 mainly expressed in neurons represent an innate neuroprotective mechanism in neonatal HI brain injury.
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Affiliation(s)
- Qingyi Ma
- The Lawrence D. Longo, MD Center for Perinatal Biology, Division of Pharmacology, Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, CA 92350, USA.
| | - Lubo Zhang
- The Lawrence D. Longo, MD Center for Perinatal Biology, Division of Pharmacology, Department of Basic Sciences, Loma Linda University School of Medicine, Loma Linda, CA 92350, USA
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23
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Shin JA, Jeong SI, Kim HW, Jang G, Ryu DR, Ahn YH, Choi JH, Choi YH, Park EM. Repression of adenosine triphosphate-binding cassette transporter ABCG2 by estrogen increases intracellular glutathione in brain endothelial cells following ischemic reperfusion injury. Neurobiol Aging 2018; 66:138-148. [PMID: 29574357 DOI: 10.1016/j.neurobiolaging.2018.02.020] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Revised: 01/31/2018] [Accepted: 02/21/2018] [Indexed: 01/29/2023]
Abstract
The adenosine triphosphate-binding cassette efflux transporter ABCG2, which is located in the blood-brain barrier limits the entry of endogenous compounds and xenobiotics into the brain, and its expression and activity are regulated by estrogen. This study was aimed to define the role of ABCG2 in estrogen-mediated neuroprotection against ischemic injury. ABCG2 protein levels before and after ischemic stroke were increased in the brain of female mice by ovariectomy, which were reversed by estrogen replacement. In brain endothelial cell line bEnd.3, estrogen reduced the basal ABCG2 protein level and efflux activity and protected cells from ischemic injury without inducing ABCG2 expression. When bEnd.3 cells were transfected with ABCG2 small interfering RNA, ischemia-induced cell death was reduced, and the intracellular concentration of glutathione, an antioxidant that is transported by ABCG2, was increased. In addition, after ischemic stroke in ovariectomized mice, estrogen prevented the reduction of intracellular glutathione level in brain microvessels. These data suggested that the suppression of ABCG2 by estrogen is involved in neuroprotection against ischemic injury by increasing intracellular glutathione, and that the modulation of ABCG2 activity offers a therapeutic target for brain diseases in estrogen-deficient aged women.
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Affiliation(s)
- Jin A Shin
- Department of Pharmacology, Tissue Injury Defense Research Center, College of Medicine, Ewha Womans University, Seoul, Republic of Korea
| | - Sae Im Jeong
- Department of Pharmacology, Tissue Injury Defense Research Center, School of Medicine, Ewha Womans University, Seoul, Republic of Korea
| | - Hye Won Kim
- Department of Pharmacology, Tissue Injury Defense Research Center, College of Medicine, Ewha Womans University, Seoul, Republic of Korea
| | - Gyeonghui Jang
- Department of Pharmacology, Tissue Injury Defense Research Center, College of Medicine, Ewha Womans University, Seoul, Republic of Korea
| | - Dong-Ryeol Ryu
- Department of Internal Medicine, Tissue Injury Defense Research Center, College of Medicine, Ewha Womans University, Seoul, Republic of Korea
| | - Young-Ho Ahn
- Department of Molecular Medicine, Tissue Injury Defense Research Center, College of Medicine, Ewha Womans University, Seoul, Republic of Korea
| | - Ji Ha Choi
- Department of Pharmacology, Tissue Injury Defense Research Center, College of Medicine, Ewha Womans University, Seoul, Republic of Korea
| | - Youn-Hee Choi
- Department of Physiology, Tissue Injury Defense Research Center, College of Medicine, Ewha Womans University, Seoul, Republic of Korea
| | - Eun-Mi Park
- Department of Pharmacology, Tissue Injury Defense Research Center, College of Medicine, Ewha Womans University, Seoul, Republic of Korea.
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24
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Dore-Duffy P, Esen N. The Microvascular Pericyte: Approaches to Isolation, Characterization, and Cultivation. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1109:53-65. [PMID: 30523589 DOI: 10.1007/978-3-030-02601-1_5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The microvascular pericyte was identified in 1873 by the French scientist Charles Benjamin Rouget and originally called the Rouget cell (Rouget.Sciences 88:916-8, 1879). However, it was not until the early 1900s that Rouget's work was confirmed, and the Rouget cell renamed the pericyte by virtue of its peri-endothelial location (Dore. Brit J Dermatol 35:398-404, 1923; Zimmermann. Z Anat Entwicklungsgesch 68:3-109, 1923). Over the years a large number of publications have emerged, but the pericyte has remained a truly enigmatic cell. This is due, in part, by the paucity of easy and reliable methods to isolate and characterize the cell as well as its heterogeneity and pluripotent characteristics. However, more recent advances in molecular genetics and development of novel cell isolation and imaging techniques have enable scientists to more readily define pericyte function. This chapter will discuss general approaches to the isolation, characterization, and propagation of primary pericytes in the establishment of cell lines. We will attempt to dispel misinterpretations about the pericyte that cloud the literature.
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Affiliation(s)
- Paula Dore-Duffy
- Department of Neurology, School of Medicine, Wayne State University, Detroit, MI, USA.
| | - Nilufer Esen
- Department of Neurology, School of Medicine, Wayne State University, Detroit, MI, USA
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25
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Kono M, Conlon EG, Lux SY, Yanagida K, Hla T, Proia RL. Bioluminescence imaging of G protein-coupled receptor activation in living mice. Nat Commun 2017; 8:1163. [PMID: 29079828 PMCID: PMC5660082 DOI: 10.1038/s41467-017-01340-7] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 09/06/2017] [Indexed: 01/04/2023] Open
Abstract
G protein-coupled receptors (GPCRs), a superfamily of cell-surface receptors involved in virtually all physiological processes, are the major target class for approved drugs. Imaging GPCR activation in real time in living animals would provide a powerful way to study their role in biology and disease. Here, we describe a mouse model that enables the bioluminescent detection of GPCR activation in real time by utilizing the clinically important GPCR, sphingosine-1-phosphate receptor 1 (S1P1). A synthetic S1P1 signaling pathway, designed to report the interaction between S1P1 and β-arrestin2 via the firefly split luciferase fragment complementation system, is genetically encoded in these mice. Upon receptor activation and subsequent β-arrestin2 recruitment, an active luciferase enzyme complex is produced, which can be detected by in vivo bioluminescence imaging. This imaging strategy reveals the dynamics and spatial specificity of S1P1 activation in normal and pathophysiologic contexts in vivo and can be applied to other GPCRs. G protein-coupled receptors are involved in numerous physiological functions, thus, they represent potential pharmaceutical targets. Here Kono et al. describe a new mouse model to image GPCR activation in real-time by exploiting firefly split luciferase fragment complementation that can be detected by bioluminescence imaging.
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Affiliation(s)
- Mari Kono
- Genetics of Development and Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, MD, 20892, USA
| | - Elizabeth G Conlon
- Genetics of Development and Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, MD, 20892, USA
| | - Samantha Y Lux
- Genetics of Development and Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, MD, 20892, USA
| | - Keisuke Yanagida
- Vascular Biology Program, Boston Children's Hospital, Department of Surgery, Harvard Medical School, Boston, MA, 02115, USA
| | - Timothy Hla
- Vascular Biology Program, Boston Children's Hospital, Department of Surgery, Harvard Medical School, Boston, MA, 02115, USA
| | - Richard L Proia
- Genetics of Development and Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, MD, 20892, USA.
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26
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Khosravi Y, Salimi A, Pourahmad J, Naserzadeh P, Seydi E. Inhalation exposure of nano diamond induced oxidative stress in lung, heart and brain. Xenobiotica 2017; 48:860-866. [DOI: 10.1080/00498254.2017.1367974] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Yahya Khosravi
- Research Center for Health, Safety and Environment (RCHSE), Alborz University of Medical Sciences, Karaj, Iran,
- Department of Occupational Health Engineering, Alborz University of Medical Sciences, Karaj, Iran,
| | - Ahmad Salimi
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Ardabil University of Medical Sciences, Ardabil, Iran,
| | - Jalal Pourahmad
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran, and
| | - Parvaneh Naserzadeh
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran, and
- Students Research Committee, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Enayatollah Seydi
- Research Center for Health, Safety and Environment (RCHSE), Alborz University of Medical Sciences, Karaj, Iran,
- Department of Occupational Health Engineering, Alborz University of Medical Sciences, Karaj, Iran,
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27
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Bo LJ, Miao Z, Wang ZF, Zhang KZ, Gao Z. A study on effect of curcumin on anticerebral aneurysm in the male albino rats. Brain Behav 2017; 7:e00729. [PMID: 28948066 PMCID: PMC5607535 DOI: 10.1002/brb3.729] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2016] [Revised: 04/07/2017] [Accepted: 04/11/2017] [Indexed: 01/27/2023] Open
Abstract
INTRODUCTION This study investigated the curcumin effect on the cerebral aneurysm. Apoptosis is known to play a fundamental role in the pathogenesis of a cerebral aneurysm. Therefore, we investigated the effect of curcumin on apoptosis of smooth muscle cells of a cerebral aneurysm-induced male albino rats. METHODS In this study, the cerebral aneurysm has been induced in the male albino rats by the CaCl2 administration. After cerebral aneurysm induction, smooth muscle cells were isolated. Cells were treated with curcumin (25 & 50 mg/kg bwt) for 48 hr. RESULTS Curcumin reduced altered mitochondrial morphology significantly, evidenced through fluorescence and confocal study. Curcumin treatment reduced the expression of p53, caspase-3, and bax/bxl-2 ratio significantly. Curcumin treatment also reversed the cellular architecture of smooth muscle cell wall significantly. Fluorescence and the confocal study confirmed the reduction in apoptosis in a cerebral aneurysm-induced smooth muscle cells of male albino rats. CONCLUSION Taking all these data together, it may suggest that the curcumin could significantly reduce the CaCl2-induced cerebral aneurysm through the inhibition of cell apoptosis in the cells.
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Affiliation(s)
- Li-Juan Bo
- Department of Infectious Disease China-Japan Union Hospital Ji Lin University Changchun China
| | - Zhuang Miao
- Department I of Neurosurgery China-Japan Union Hospital Ji Lin University Changchun China
| | - Zhan-Feng Wang
- Department I of Neurosurgery China-Japan Union Hospital Ji Lin University Changchun China
| | - Kai-Zhi Zhang
- Department I of Neurosurgery China-Japan Union Hospital Ji Lin University Changchun China
| | - Zheng Gao
- Department of Neurosurgery People's Hospital of Dandong City Dandong China
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28
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Cai G, Lai B, Hong H, Lin P, Chen W, Zhu Z, Chen H. Effects of cryopreservation on excretory function, cellular adhesion molecules and vessel lumen formation in human umbilical vein endothelial cells. Mol Med Rep 2017; 16:547-552. [PMID: 28586042 PMCID: PMC5482135 DOI: 10.3892/mmr.2017.6664] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Accepted: 02/23/2017] [Indexed: 01/12/2023] Open
Abstract
Cryopreservation is widely used in regenerative medicine for tissue preservation. In the present study, the effects of cryopreservation on excretory function, cellular adhesion molecules and vessel lumen formation in human umbilical vein endothelial cells (HUVECs) were investigated. After 0, 4, 8, 12 or 24 weeks of cryopreservation in liquid nitrogen, the HUVECs were thawed. The excretory functions markers (endothelin-1, prostaglandin E1, von Willebrand factor and nitric oxide) of HUVECs were measured by ELISA assay. The expression of intercellular adhesion molecule-1 (ICAM-1) in HUVECs was analyzed using flow cytometry. An angiogenesis assay was used to determine the angiogeneic capabilities of the thawed HUVECs. The results demonstrated that cryopreserved/thawed and recultivated HUVECs were unsuitable for tissue-engineered microvascular construction. Specifically, the excretory function of the cells was significantly decreased in the post-cryopreserved HUVECs at 24 weeks. In addition, the level of ICAM-1 in HUVECs was significantly upregulated from the fourth week of cryopreservation. Furthermore, the tube-like structure-forming potential was weakened with increasing cryopreservation duration, and the numbers of lumen and the length of the pipeline were decreased in the thawed HUVECs, in a time-dependent manner. In conclusion, the results of the present study revealed that prolonged cryopreservation may lead to HUVEC dysfunction and did not create stable cell lines for tissue-engineered microvascular construction.
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Affiliation(s)
- Guoping Cai
- Department of Orthopaedics, Taizhou Hospital of Zhejiang, Wenzhou Medical University, Taizhou, Zhejiang 317000, P.R. China
| | - Binbin Lai
- Department of Infectious Diseases, Taizhou Hospital of Zhejiang, Wenzhou Medical University, Taizhou, Zhejiang 317000, P.R. China
| | - Huaxing Hong
- Department of Orthopaedics, Taizhou Hospital of Zhejiang, Wenzhou Medical University, Taizhou, Zhejiang 317000, P.R. China
| | - Peng Lin
- Department of Orthopaedics, Taizhou Hospital of Zhejiang, Wenzhou Medical University, Taizhou, Zhejiang 317000, P.R. China
| | - Weifu Chen
- Department of Orthopaedics, Taizhou Hospital of Zhejiang, Wenzhou Medical University, Taizhou, Zhejiang 317000, P.R. China
| | - Zhong Zhu
- Department of Orthopaedics, Taizhou Hospital of Zhejiang, Wenzhou Medical University, Taizhou, Zhejiang 317000, P.R. China
| | - Haixiao Chen
- Department of Orthopaedics, Taizhou Hospital of Zhejiang, Wenzhou Medical University, Taizhou, Zhejiang 317000, P.R. China
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29
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Siqueira M, Francis D, Gisbert D, Gomes FCA, Stipursky J. Radial Glia Cells Control Angiogenesis in the Developing Cerebral Cortex Through TGF-β1 Signaling. Mol Neurobiol 2017; 55:3660-3675. [PMID: 28523566 DOI: 10.1007/s12035-017-0557-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Accepted: 04/12/2017] [Indexed: 10/19/2022]
Abstract
Neuroangiogenesis in the developing central nervous system is controlled by interactions between endothelial cells (ECs) and radial glia (RG) neural stem cells, although RG-derived molecules implicated in these events are not fully known. Here, we investigated the role of RG-secreted TGF-β1, in angiogenesis in the developing cerebral cortex. By isolation of murine microcapillary brain endothelial cells (MBECs), we demonstrate that conditioned medium from RG cultures (RG-CM) promoted MBEC migration and formation of vessel-like structures in vitro, in a TGF-β1-dependent manner. These events were followed by endothelial regulation of GPR124 and BAI-1 gene expression by RG-CM. Proteome profile of RG-CM identified angiogenesis-related molecules IGFBP2/3, osteopontin, endostatin, SDF1, fractalkine, TIMP1/4, Ang-1, pentraxin3, and Cyr61, some of them modulated by TGF-β1 induction. In vivo gain and loss of function assays targeting RG cells demonstrates a specific TGF-β1-dependent control of blood vessels branching in the cerebral cortex. Together, our results point to TGF-β1 signaling pathway as a potential mediator of the RG-EC interactions and shed light to the key role of RG in paving the brain vascular network.
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Affiliation(s)
- Michele Siqueira
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Daniel Francis
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Diego Gisbert
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | | | - Joice Stipursky
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil. .,Laboratório de Neurobiologia Celular, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro - Centro de Ciências da Saúde, Bloco F, Sala F15, Ilha do Fundão, Rio de Janeiro, RJ, 21949-902, Brazil.
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Cerebrovascular Angiogenic Reprogramming upon LRP1 Repression: Impact on Sphingosine-1-Phosphate-Mediated Signaling in Brain Endothelial Cell Chemotactism. Mol Neurobiol 2017; 55:3551-3563. [PMID: 28516428 DOI: 10.1007/s12035-017-0614-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 05/11/2017] [Indexed: 12/28/2022]
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31
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Vascular protective effects of KLF2 on Aβ-induced toxicity: Implications for Alzheimer’s disease. Brain Res 2017; 1663:174-183. [DOI: 10.1016/j.brainres.2017.01.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2016] [Revised: 12/29/2016] [Accepted: 01/02/2017] [Indexed: 11/19/2022]
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32
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Chan GNY, Cannon RE. Assessment of Ex Vivo Transport Function in Isolated Rodent Brain Capillaries. ACTA ACUST UNITED AC 2017; 76:7.16.1-7.16.16. [PMID: 28306152 DOI: 10.1002/cpph.21] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The blood-brain barrier plays an important role in neuroprotection; however, it can be a major obstacle for drug delivery to the brain. This barrier primarily resides in the brain capillaries and functions as an interface between the brain and peripheral blood circulation. Several anatomical and biochemical elements of the blood-brain barrier are essential to regulate the permeability of nutrients, ions, hormones, toxic metabolites, and xenobiotics into and out of the brain. In particular, high expression of ATP-driven efflux transporters at the blood-brain barrier is a major obstacle in the delivery of CNS pharmacotherapeutics to the brain. The complete understanding of these elements can offer insights on how to modulate barrier functions for neuroprotection against CNS drug toxicity and to enhance drug delivery to the brain. In the literature, preclinical models of the blood-brain barrier are widely utilized to predict drug pharmacokinetics and pharmacodynamics properties in the brain. In addition, these models are essential tools to investigate cellular mechanisms and novel interventions that alter barrier function and permeability. This unit presents procedures to isolate fresh and viable rodent brain capillaries for the assessment of ex vivo transport activity at the blood-brain barrier. © 2017 by John Wiley & Sons, Inc.
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Affiliation(s)
- Gary N Y Chan
- National Institutes of Health, National Institute of Environmental Health Sciences, Intracellular Regulatory Group, Signal Transduction Laboratory, Research Triangle Park, North Carolina, USA
| | - Ronald E Cannon
- National Institutes of Health, National Institute of Environmental Health Sciences, Intracellular Regulatory Group, Signal Transduction Laboratory, Research Triangle Park, North Carolina, USA
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33
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Quan R, Du W, Zheng X, Xu S, Li Q, Ji X, Wu X, Shao R, Yang D. VEGF165 induces differentiation of hair follicle stem cells into endothelial cells and plays a role in in vivo angiogenesis. J Cell Mol Med 2017; 21:1593-1604. [PMID: 28244687 PMCID: PMC5542910 DOI: 10.1111/jcmm.13089] [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: 07/03/2016] [Accepted: 12/13/2016] [Indexed: 01/20/2023] Open
Abstract
Within the vascular endothelial growth factor (VEGF) family of five subtypes, VEGF165 secreted by endothelial cells has been identified to be the most active and widely distributed factor that plays a vital role in courses of angiogenesis, vascularization and mesenchymal cell differentiation. Hair follicle stem cells (HFSCs) can be harvested from the bulge region of the outer root sheath of the hair follicle and are adult stem cells that have multi-directional differentiation potential. Although the research on differentiation of stem cells (such as fat stem cells and bone marrow mesenchymal stem cells) to the endothelial cells has been extensive, but the various mechanisms and functional forms are unclear. In particular, study on HFSCs' directional differentiation into vascular endothelial cells using VEGF165 has not been reported. In this study, VEGF165 was used as induction factor to induce the differentiation from HFSCs into vascular endothelial cells, and the results showed that Notch signalling pathway might affect the differentiation efficiency of vascular endothelial cells. In addition, the in vivo transplantation experiment provided that HFSCs could promote angiogenesis, and the main function is to accelerate host-derived neovascularization. Therefore, HFSCs could be considered as an ideal cell source for vascular tissue engineering and cell transplantation in the treatment of ischaemic diseases.
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Affiliation(s)
- Renfu Quan
- Research Institute of Orthopedics, The Affiliated JiangNan Hospital of Zhejiang Chinese Medical University, Hangzhou, China
| | - Weibin Du
- Research Institute of Orthopedics, The Affiliated JiangNan Hospital of Zhejiang Chinese Medical University, Hangzhou, China
| | - Xuan Zheng
- Research Institute of Orthopedics, The Affiliated JiangNan Hospital of Zhejiang Chinese Medical University, Hangzhou, China
| | - Shichao Xu
- Research Institute of Orthopedics, The Affiliated JiangNan Hospital of Zhejiang Chinese Medical University, Hangzhou, China
| | - Qiang Li
- Research Institute of Orthopedics, The Affiliated JiangNan Hospital of Zhejiang Chinese Medical University, Hangzhou, China
| | - Xing Ji
- Department of Pharmacology, School of Medical, Zhejiang University, Hangzhou, China
| | - Ximei Wu
- Department of Pharmacology, School of Medical, Zhejiang University, Hangzhou, China
| | - Rongxue Shao
- Research Institute of Orthopedics, Zhejiang Chinese Medical University, Hangzhou, Zhejiang Province, China
| | - Disheng Yang
- Research Institute of Orthopedics, The Second Affiliated Hospital, School of Medical, Zhejiang University, Hangzhou, China
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Rosa AI, Grade S, Santos SD, Bernardino L, Chen TC, Relvas J, Hofman FM, Agasse F. Heterocellular Contacts with Mouse Brain Endothelial Cells Via Laminin and α6β1 Integrin Sustain Subventricular Zone (SVZ) Stem/Progenitor Cells Properties. Front Cell Neurosci 2016; 10:284. [PMID: 28018177 PMCID: PMC5156690 DOI: 10.3389/fncel.2016.00284] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2016] [Accepted: 11/28/2016] [Indexed: 01/08/2023] Open
Abstract
Neurogenesis in the subventricular zone (SVZ) is regulated by diffusible factors and cell–cell contacts. In vivo, SVZ stem cells are associated with the abluminal surface of blood vessels and such interactions are thought to regulate their neurogenic capacity. SVZ neural stem cells (NSCs) have been described to contact endothelial-derived laminin via α6β1 integrin. To elucidate whether heterocellular contacts with brain endothelial cells (BEC) regulate SVZ cells neurogenic capacities, cocultures of SVZ neurospheres and primary BEC, both obtained from C57BL/6 mice, were performed. The involvement of laminin-integrin interactions in SVZ homeostasis was tested in three ways. Firstly, SVZ cells were analyzed following incubation of BEC with the protein synthesis inhibitor cycloheximide (CHX) prior to coculture, a treatment expected to decrease membrane proteins. Secondly, SVZ cells were cocultured with BEC in the presence of an anti-α6 integrin neutralizing antibody. Thirdly, BEC were cultured with β1−/− SVZ cells. We showed that contact with BEC supports, at least in part, proliferation and stemness of SVZ cells, as evaluated by the number of BrdU positive (+) and Sox2+ cells in contact with BEC. These effects are dependent on BEC-derived laminin binding to α6β1 integrin and are decreased in cocultures incubated with anti-α6 integrin neutralizing antibody and in cocultures with SVZ β1−/− cells. Moreover, BEC-derived laminin sustains stemness in SVZ cell cultures via activation of the Notch and mTOR signaling pathways. Our results show that BEC/SVZ interactions involving α6β1 integrin binding to laminin, contribute to SVZ cell proliferation and stemness.
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Affiliation(s)
- Alexandra I Rosa
- Centre for Neuroscience and Cell Biology, University of CoimbraCoimbra, Portugal; Department of Pathology, University of Southern CaliforniaLos Angeles, CA, USA; Department of Neurological Surgery, University of Southern CaliforniaLos Angeles, CA, USA
| | - Sofia Grade
- Centre for Neuroscience and Cell Biology, University of Coimbra Coimbra, Portugal
| | - Sofia D Santos
- Glial Cell Biology Group, Institute for Molecular and Cell Biology - IBMCPorto, Portugal; Instituto de Investigação e Inovação em Saúde, Universidade do PortoPorto, Portugal
| | - Liliana Bernardino
- Centre for Neuroscience and Cell Biology, University of CoimbraCoimbra, Portugal; Health Sciences Research Centre, Faculty of Health Sciences, University of Beira InteriorCovilhã, Portugal
| | - Thomas C Chen
- Department of Neurological Surgery, University of Southern California Los Angeles, CA, USA
| | - João Relvas
- Glial Cell Biology Group, Institute for Molecular and Cell Biology - IBMCPorto, Portugal; Instituto de Investigação e Inovação em Saúde, Universidade do PortoPorto, Portugal
| | - Florence M Hofman
- Department of Pathology, University of Southern California Los Angeles, CA, USA
| | - Fabienne Agasse
- Centre for Neuroscience and Cell Biology, University of CoimbraCoimbra, Portugal; Department of Pathology, University of Southern CaliforniaLos Angeles, CA, USA; Department of Neurological Surgery, University of Southern CaliforniaLos Angeles, CA, USA
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35
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A dynamic in vivo-like organotypic blood-brain barrier model to probe metastatic brain tumors. Sci Rep 2016; 6:36670. [PMID: 27830712 PMCID: PMC5103210 DOI: 10.1038/srep36670] [Citation(s) in RCA: 125] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 10/10/2016] [Indexed: 12/22/2022] Open
Abstract
The blood-brain barrier (BBB) restricts the uptake of many neuro-therapeutic molecules, presenting a formidable hurdle to drug development in brain diseases. We proposed a new and dynamic in vivo-like three-dimensional microfluidic system that replicates the key structural, functional and mechanical properties of the blood-brain barrier in vivo. Multiple factors in this system work synergistically to accentuate BBB-specific attributes-permitting the analysis of complex organ-level responses in both normal and pathological microenvironments in brain tumors. The complex BBB microenvironment is reproduced in this system via physical cell-cell interaction, vascular mechanical cues and cell migration. This model possesses the unique capability to examine brain metastasis of human lung, breast and melanoma cells and their therapeutic responses to chemotherapy. The results suggest that the interactions between cancer cells and astrocytes in BBB microenvironment might affect the ability of malignant brain tumors to traverse between brain and vascular compartments. Furthermore, quantification of spatially resolved barrier functions exists within a single assay, providing a versatile and valuable platform for pharmaceutical development, drug testing and neuroscientific research.
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36
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Xu H, Li Z, Guo Y, Peng X, Qin J. Probing the response of lung tumor cells to inflammatory microvascular endothelial cells on fluidic microdevice. Electrophoresis 2016; 38:311-319. [DOI: 10.1002/elps.201600278] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 08/31/2016] [Accepted: 08/31/2016] [Indexed: 01/14/2023]
Affiliation(s)
- Hui Xu
- State Key Laboratory of Fine Chemicals; Dalian University of Technology; Dalian P. R. China
- Dalian Institute of Chemical Physics; Chinese Academy of Sciences; Dalian P. R. China
| | - Zhongyu Li
- State Key Laboratory of Fine Chemicals; Dalian University of Technology; Dalian P. R. China
- Dalian Institute of Chemical Physics; Chinese Academy of Sciences; Dalian P. R. China
| | - Yaqiong Guo
- Dalian Institute of Chemical Physics; Chinese Academy of Sciences; Dalian P. R. China
| | - Xiaojun Peng
- State Key Laboratory of Fine Chemicals; Dalian University of Technology; Dalian P. R. China
| | - Jianhua Qin
- Dalian Institute of Chemical Physics; Chinese Academy of Sciences; Dalian P. R. China
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37
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Abstract
We have recently demonstrated that brain endothelial cells cross-present parasite antigen during mouse experimental cerebral malaria (ECM). Here we describe a 2-d protocol to detect cross-presentation by isolating the brain microvessels and incubating them with a reporter cell line that expresses lacZ upon detection of the relevant peptide-major histocompatibility complex. After X-gal staining, a typical positive result consists of hundreds of blue spots, compared with fewer than 20 spots from a naive brain. The assay is generalizable to other disease contexts by using reporter cells that express appropriate specific T cell receptors. Also described is the protocol for culturing endothelial cells from brain microvessels isolated from naive mice. After 7-10 d, an in vitro cross-presentation assay can be performed by adding interferon-γ, antigen (e.g., Plasmodium berghei-infected red blood cells) and reporter cells in sequence over 3 d. This is useful for comparing different antigen forms or for probing the effects of various interventions.
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38
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Xu M, Xu H, Qin Z, Zhang J, Yang X, Xu F. Increased expression of angiogenic factors in cultured human brain arteriovenous malformation endothelial cells. Cell Biochem Biophys 2015; 70:443-7. [PMID: 24771337 DOI: 10.1007/s12013-014-9937-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
To compare the mRNA level of angiogenic factor vascular endothelial growth factor (VEGF), matrix metalloproteinases (MMP)-2, and MMP-9 in cultured human brain arteriovenous malformation (AVM) endothelial cells (ECs) and normal brain endothelial cells (BECs). Tissue explants both from deformed vessels of AVM and normal microvessel were put into culture for endothelial cells. After the monolayer adherent ECs reached confluence, they were tested with endothelial specific marker CD34 and von Willebrand factor (vWF) by immunochemical assay. mRNA levels of VEGF-A, MMP-2, and MMP-9 in AVM endothelial cells (AVMECs) and BECs were measured by PCR. Immunostaining confirmed that more than 95 % of the cultured cells were CD34 (Fig. 1b) and/or vWF positive. Expression levels of VEGF-A and MMP-2 mRNAs were significantly higher in AVMECs than in BECs. The MMP-9 level was also increased in AVMECs, but the difference was not statistically significant. Vascular tissue explants adherent method is a better approach for isolation and culture of AVMECs. Cultured AVMECs expressed higher angiogenic factors (VEGF, MMP-2) than the controlled BECs, implicating angiogenesis plays an important role in the pathogenesis of AVM.
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Affiliation(s)
- Ming Xu
- Department of Anesthesiology, Fudan University, Shanghai, China
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39
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Zhao Z, Sagare AP, Ma Q, Halliday MR, Kong P, Kisler K, Winkler EA, Ramanathan A, Kanekiyo T, Bu G, Owens NC, Rege SV, Si G, Ahuja A, Zhu D, Miller CA, Schneider JA, Maeda M, Maeda T, Sugawara T, Ichida JK, Zlokovic BV. Central role for PICALM in amyloid-β blood-brain barrier transcytosis and clearance. Nat Neurosci 2015; 18:978-87. [PMID: 26005850 PMCID: PMC4482781 DOI: 10.1038/nn.4025] [Citation(s) in RCA: 310] [Impact Index Per Article: 34.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 04/21/2015] [Indexed: 12/11/2022]
Abstract
PICALM is a highly validated genetic risk factor for Alzheimer's disease (AD). We found that reduced expression of PICALM in AD and murine brain endothelium correlated with amyloid-β (Aβ) pathology and cognitive impairment. Moreover, Picalm deficiency diminished Aβ clearance across the murine blood-brain barrier (BBB) and accelerated Aβ pathology in a manner that was reversible by endothelial PICALM re-expression. Using human brain endothelial monolayers, we found that PICALM regulated PICALM/clathrin-dependent internalization of Aβ bound to the low density lipoprotein receptor related protein-1, a key Aβ clearance receptor, and guided Aβ trafficking to Rab5 and Rab11, leading to Aβ endothelial transcytosis and clearance. PICALM levels and Aβ clearance were reduced in AD-derived endothelial monolayers, which was reversible by adenoviral-mediated PICALM transfer. Inducible pluripotent stem cell-derived human endothelial cells carrying the rs3851179 protective allele exhibited higher PICALM levels and enhanced Aβ clearance. Thus, PICALM regulates Aβ BBB transcytosis and clearance, which has implications for Aβ brain homeostasis and clearance therapy.
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Affiliation(s)
- Zhen Zhao
- Zilkha Neurogenetic Institute and Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Abhay P. Sagare
- Zilkha Neurogenetic Institute and Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Qingyi Ma
- Zilkha Neurogenetic Institute and Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Matthew R. Halliday
- Zilkha Neurogenetic Institute and Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Pan Kong
- Zilkha Neurogenetic Institute and Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Kassandra Kisler
- Zilkha Neurogenetic Institute and Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Ethan A. Winkler
- Zilkha Neurogenetic Institute and Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
- Department of Neurological Surgery, University of California San Francisco, San Francisco, CA 94143, USA
| | - Anita Ramanathan
- Zilkha Neurogenetic Institute and Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Takahisa Kanekiyo
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Guojun Bu
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Nelly Chuqui Owens
- Zilkha Neurogenetic Institute and Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Sanket V. Rege
- Zilkha Neurogenetic Institute and Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Gabriel Si
- Zilkha Neurogenetic Institute and Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Ashim Ahuja
- Zilkha Neurogenetic Institute and Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Donghui Zhu
- Department of Chemical, Biological and Bio–Engineering, North Carolina Agricultural and Technical State University, Greensboro, NC 27411, USA
| | - Carol A. Miller
- Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Julie A. Schneider
- Alzheimer’s Disease Center, Rush University Medical Center, Chicago, IL 60612, USA
| | - Manami Maeda
- Division of Hematopoietic Stem Cell and Leukemia Research, Beckman Research Institute of the City of Hope, Duarte, CA 91010, USA
- Division of Hematology, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Takahiro Maeda
- Division of Hematopoietic Stem Cell and Leukemia Research, Beckman Research Institute of the City of Hope, Duarte, CA 91010, USA
- Division of Hematology, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Tohru Sugawara
- Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, and Department of Stem Cell Biology and Regenerative Medicine, University of Southern California, 1425 San Pablo Street, BCC 307, Los Angeles, CA 90089, USA
| | - Justin K. Ichida
- Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, and Department of Stem Cell Biology and Regenerative Medicine, University of Southern California, 1425 San Pablo Street, BCC 307, Los Angeles, CA 90089, USA
| | - Berislav V. Zlokovic
- Zilkha Neurogenetic Institute and Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
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40
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Regional and stage-specific effects of prospectively purified vascular cells on the adult V-SVZ neural stem cell lineage. J Neurosci 2015; 35:4528-39. [PMID: 25788671 DOI: 10.1523/jneurosci.1188-14.2015] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Adult neural stem cells reside in specialized niches. In the ventricular-subventricular zone (V-SVZ), quiescent neural stem cells (qNSCs) become activated (aNSCs), and generate transit amplifying cells (TACs), which give rise to neuroblasts that migrate to the olfactory bulb. The vasculature is an important component of the adult neural stem cell niche, but whether vascular cells in neurogenic areas are intrinsically different from those elsewhere in the brain is unknown. Moreover, the contribution of pericytes to the neural stem cell niche has not been defined. Here, we describe a rapid FACS purification strategy to simultaneously isolate primary endothelial cells and pericytes from brain microregions of nontransgenic mice using CD31 and CD13 as surface markers. We compared the effect of purified vascular cells from a neurogenic (V-SVZ) and non-neurogenic brain region (cortex) on the V-SVZ stem cell lineage in vitro. Endothelial and pericyte diffusible signals from both regions differentially promote the proliferation and neuronal differentiation of qNSCs, aNSCs, and TACs. Unexpectedly, diffusible cortical signals had the most potent effects on V-SVZ proliferation and neurogenesis, highlighting the intrinsic capacity of non-neurogenic vasculature to support stem cell behavior. Finally, we identify PlGF-2 as an endothelial-derived mitogen that promotes V-SVZ cell proliferation. This purification strategy provides a platform to define the functional and molecular contribution of vascular cells to stem cell niches and other brain regions under different physiological and pathological states.
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41
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Wang H, Hong LJ, Huang JY, Jiang Q, Tao RR, Tan C, Lu NN, Wang CK, Ahmed MM, Lu YM, Liu ZR, Shi WX, Lai EY, Wilcox CS, Han F. P2RX7 sensitizes Mac-1/ICAM-1-dependent leukocyte-endothelial adhesion and promotes neurovascular injury during septic encephalopathy. Cell Res 2015; 25:674-90. [PMID: 25998681 PMCID: PMC4456628 DOI: 10.1038/cr.2015.61] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2014] [Revised: 02/10/2015] [Accepted: 03/12/2015] [Indexed: 12/15/2022] Open
Abstract
Septic encephalopathy (SE) is a critical factor determining sepsis mortality. Vascular inflammation is known to be involved in SE, but the molecular events that lead to the development of encephalopathy remain unclear. Using time-lapse in vivo two-photon laser scanning microscopy, we provide the first direct evidence that cecal ligation and puncture in septic mice induces microglial trafficking to sites adjacent to leukocyte adhesion on inflamed cerebral microvessels. Our data further demonstrate that septic injury increased the chemokine CXCL1 level in brain endothelial cells by activating endothelial P2RX7 and eventually enhanced the binding of Mac-1 (CD11b/CD18)-expressing leukocytes to endothelial ICAM-1. In turn, leukocyte adhesion upregulated endothelial CX3CL1, thereby triggering microglia trafficking to the injured site. The sepsis-induced increase in endothelial CX3CL1 was abolished in CD18 hypomorphic mutant mice. Inhibition of the P2RX7 pathway not only decreased endothelial ICAM-1 expression and leukocyte adhesion but also prevented microglia overactivation, reduced brain injury, and consequently doubled the early survival of septic mice. These results demonstrate the role of the P2RX7 pathway in linking neurovascular inflammation to brain damage in vivo and provide a rationale for targeting endothelial P2RX7 for neurovascular protection during SE.
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Affiliation(s)
- Huan Wang
- 1] Institute of Pharmacology and Toxicology, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China [2] Key Laboratory of Carbohydrate and Lipid Metabolism Research, College of Life Science and Technology, Dalian University, Dalian, Liaoning 116622, China
| | - Ling-Juan Hong
- Institute of Pharmacology and Toxicology, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Ji-Yun Huang
- Institute of Pharmacology and Toxicology, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Quan Jiang
- Institute of Pharmacology and Toxicology, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Rong-Rong Tao
- Institute of Pharmacology and Toxicology, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Chao Tan
- Institute of Pharmacology and Toxicology, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Nan-Nan Lu
- Institute of Pharmacology and Toxicology, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Cheng-Kun Wang
- Institute of Pharmacology and Toxicology, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Muhammad M Ahmed
- Institute of Pharmacology and Toxicology, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Ying-Mei Lu
- School of Medicine, Zhejiang University City College, Hangzhou, Zhejiang 310015, China
| | - Zhi-Rong Liu
- Department of Neurology, Second Affiliated Hospital of Zhejiang University, School of Medicine, Hangzhou, Zhejiang 310009, China
| | - Wei-Xing Shi
- Department of Basic Sciences, Loma Linda University Health Schools of Medicine, Pharmacy, and Behavioral Health, Loma Linda, CA 92350, USA
| | - En-Yin Lai
- Department of Physiology, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310058, China
| | - Christopher S Wilcox
- Hypertension, Kidney, and Vascular Research Center, Georgetown University Medical Center, Washington DC 20007, USA
| | - Feng Han
- Institute of Pharmacology and Toxicology, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, Zhejiang 310058, China
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Wu F, Zhao Y, Jiao T, Shi D, Zhu X, Zhang M, Shi M, Zhou H. CXCR2 is essential for cerebral endothelial activation and leukocyte recruitment during neuroinflammation. J Neuroinflammation 2015; 12:98. [PMID: 25990934 PMCID: PMC4438521 DOI: 10.1186/s12974-015-0316-6] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Accepted: 04/30/2015] [Indexed: 01/05/2023] Open
Abstract
Background Chemokines and chemokine receptors cooperate to promote immune cell recruitment to the central nervous system (CNS). In this study, we investigated the roles of CXCR2 and CXCL1 in leukocyte recruitment to the CNS using a murine model of neuroinflammation. Methods Wild-type (WT), CXCL1−/−, and CXCR2−/− mice each received an intracerebroventricular (i.c.v.) injection of lipopolysaccharide (LPS). Esterase staining and intravital microscopy were performed to examine neutrophil recruitment to the brain. To assess endothelial activation in these mice, the expression of adhesion molecules was measured via quantitative real-time polymerase chain reaction (PCR) and Western blotting. To identify the cellular source of functional CXCR2, chimeric mice were generated by transferring bone marrow cells between the WT and CXCR2−/− mice. Results Expression levels of the chemokines CXCL1, CXCL2, and CXCL5 were significantly increased in the brain following the i.c.v. injection of LPS. CXCR2 or CXCL1 deficiency blocked neutrophil infiltration and leukocyte recruitment in the cerebral microvessels. In the CXCR2−/− and CXCL1−/− mice, the cerebral endothelial expression of adhesion molecules such as P-selectin and VCAM-1 was dramatically reduced. Furthermore, the bone marrow transfer experiments demonstrated that CXCR2 expression on CNS-residing cells is essential for cerebral endothelial activation and leukocyte recruitment. Compared with microglia, cultured astrocytes secreted a much higher level of CXCL1 in vitro. Astrocyte culture conditioned medium significantly increased the expression of VCAM-1 and ICAM-1 in cerebral endothelial cells in a CXCR2-dependent manner. Additionally, CXCR2 messenger RNA (mRNA) expression in cerebral endothelial cells but not in microglia or astrocytes was increased following tumor necrosis factor-α (TNF-α) stimulation. The intravenous injection of the CXCR2 antagonist SB225002 significantly inhibited endothelial activation and leukocyte recruitment to cerebral microvessels. Conclusions CXCL1 secreted by astrocytes and endothelial CXCR2 play essential roles in cerebral endothelial activation and subsequent leukocyte recruitment during neuroinflammation.
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Affiliation(s)
- Fengjiao Wu
- Department of Immunology, Nanjing Medical University, 140 Hanzhong Road, Nanjing, JS, 210029, China.
| | - Yawei Zhao
- Department of Immunology, Nanjing Medical University, 140 Hanzhong Road, Nanjing, JS, 210029, China.
| | - Tian Jiao
- Department of Immunology, Nanjing Medical University, 140 Hanzhong Road, Nanjing, JS, 210029, China.
| | - Dongyan Shi
- Department of Immunology, Nanjing Medical University, 140 Hanzhong Road, Nanjing, JS, 210029, China.
| | - Xingxing Zhu
- Department of Immunology, Nanjing Medical University, 140 Hanzhong Road, Nanjing, JS, 210029, China.
| | - Mingshun Zhang
- Department of Immunology, Nanjing Medical University, 140 Hanzhong Road, Nanjing, JS, 210029, China.
| | - Meiqing Shi
- Division of Immunology, Virginia-Maryland College of Veterinary Medicine, University of Maryland, College Park, Maryland, MD, 20742, USA.
| | - Hong Zhou
- Department of Immunology, Nanjing Medical University, 140 Hanzhong Road, Nanjing, JS, 210029, China.
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Russell JS, Brown JM. Circulating mouse Flk1+/c-Kit+/CD45- cells function as endothelial progenitors cells (EPCs) and stimulate the growth of human tumor xenografts. Mol Cancer 2014; 13:177. [PMID: 25047738 PMCID: PMC4112847 DOI: 10.1186/1476-4598-13-177] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Accepted: 06/27/2014] [Indexed: 12/14/2022] Open
Abstract
Background Endothelial progenitor cells (EPCs) have been demonstrated to have stem-cell like as well as mature endothelial functions. However, controversy remains as to their origins, immunophenotypic markings, and contribution to the tumor vascular network and tumor survival. Methods Flow cytometric analysis and sorting was used to isolate Flk-1+/c-Kit+/CD45- cells. Matrigel and methycellulose assays, flow cytometry, and gene array analyses were performed to characterize several murine EPC cell populations. Human tumor xenografts were used to evaluate the impact of EPCs on tumor growth and vascular development. Results Flk-1+/c-Kit+/CD45- cells were present at low levels in most murine organs with the highest levels in adipose, aorta/vena cava, and lung tissues. Flk-1+/c-Kit+/CD45- cells demonstrated stem cell qualities through colony forming assays and mature endothelial function by expression of CD31, uptake of acLDL, and vascular structure formation in matrigel. High passage EPCs grown in vitro became more differentiated and lost stem-cell markers. EPCs were found to have hemangioblastic properties as demonstrated by the ability to rescue mice given whole body radiation. Systemic injection of EPCs increased the growth of human xenograft tumors and vessel density. Conclusions Flk-1+/C-Kit+/CD45- cells function as endothelial progenitor cells. EPCs are resident in most murine tissue types and localize to human tumor xenografts. Furthermore, the EPC population demonstrates stem-cell and mature endothelial functions and promoted the growth of tumors through enhanced vascular network formation. Given the involvement of EPCs in tumor development, this unique host-derived population may be an additional target to consider for anti-neoplastic therapy.
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Affiliation(s)
- Jeffery S Russell
- Head and Neck/Endocrine Oncology, Moffitt Cancer Center, 12902 Magnolia Drive, Tampa, FL 33612, USA.
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Yang H, Chen J, Shen ZW, Zhou XJ, Ji GZ. Deaggregators inhibit TNF-α-induced leukocyte adhesion in vitro by breaking up hydrophobic lipophilic interactions. Acta Pharmacol Sin 2014; 35:907-15. [PMID: 24930485 DOI: 10.1038/aps.2014.32] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Accepted: 03/21/2014] [Indexed: 01/13/2023] Open
Abstract
AIM Deaggregators (deAgrs) are nontoxic organic molecules that possess the ability to deaggregate simple aggregates formed by hydrophobic lipophilic interactions (HLI). Since HLI-driven organic molecule aggregates may induce leukocyte adhesion, we investigated the influence of deAgrs on TNF-α-mediated leukocyte adhesion in vitro. METHODS For adhesion studies, vascular endothelial cells or smooth muscle cells monolayers were treated with TNF-α (10 μg/L) and deAgrs for 24 h, followed by addition of monocytes or neutrophils suspension. The non-adherent leukocytes were rinsed, and the number of attached leukocytes was measured using an ELISA plate reader. Simultaneously, fluorescence probes Np-12 and Np-Ch were used to measure the deaggregating efficiencies of these deAgrs. RESULTS Among the nine deAgrs tested,eight significantly reduced the cell adhesion rates with the order of efficiencies: 260 > 160 > 568 > ZPMOP > R68 > 640 > TB6PMOP > CNS, but TBHQ had no effect. The deAgrs for deaggregating an aggregated probe (Np-12 or Np-Ch) exhibited a similar order of efficiencies: 260 > 160 > 568 > ZPMOP > R68 > 640 > TB6PMOP > CNS > 12-AA > 11-AA > TBHQ. Spearman correlation coefficient analyses indicated that the adherent rates of leukocytes to endothelial cells or smooth muscle cells treated with deAgrs had significantly negative correlation to their deaggregating abilities. CONCLUSION DeAgrs effectively inhibit TNF-α-mediated leukocyte adhesion in vitro by breaking up hydrophobic lipophilic interactions, thus may be further tested for blocking atherogenesis.
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Wang Z, Moran E, Ding L, Cheng R, Xu X, Ma JX. PPARα regulates mobilization and homing of endothelial progenitor cells through the HIF-1α/SDF-1 pathway. Invest Ophthalmol Vis Sci 2014; 55:3820-32. [PMID: 24845641 DOI: 10.1167/iovs.13-13396] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
PURPOSE The mechanism for the antiangiogenic activity of peroxisome proliferator-activated receptor alpha (PPARα) remains incompletely understood. Endothelial progenitor cells (EPC) are known to participate in neovascularization (NV). The purpose of this study was to investigate whether PPARα regulates EPC during retinal NV. METHODS Retinal NV was induced by oxygen-induced retinopathy (OIR). Mice with OIR were injected intraperitoneally with the PPARα agonist fenofibric acid (FA) or with adenovirus expressing PPARα (Ad-PPARα). Flow cytometry was used to quantify circulating and retinal EPC. Serum stromal cell-derived factor 1 (SDF-1) levels were measured by ELISA. Hypoxia was induced in primary human retinal capillary endothelial cells (HRCEC) and mouse brain endothelial cells (MBEC) by CoCl2. Levels of SDF-1 and hypoxia-inducible factor 1 alpha (HIF-1α) were measured by Western blotting. RESULTS Fenofibric acid and overexpression of PPARα attenuated the increase of circulating and retinal EPC, correlating with suppressed retinal NV in OIR mice at P17. The PPARα knockout enhanced the OIR-induced increase of circulating and retinal EPC. Fenofibric acid decreased retinal HIF-1α and SDF-1 levels as well as serum SDF-1 levels in the OIR model. In HRCEC, PPARα inhibited HIF-1α nuclear translocation and SDF-1 overexpression induced by hypoxia. Further, MBEC from PPARα(-/-) mice showed more prominent activation of HIF-1α and overexpression of SDF-1 induced by hypoxia, compared with the wild-type (WT) MBEC. PPARα failed to block SDF-1 overexpression induced by a constitutively active mutant of HIF-1α, suggesting that regulation of SDF-1 by PPARα was through blockade of HIF-1α activation. CONCLUSIONS Peroxisome proliferator-activated receptor alpha suppresses ischemia-induced EPC mobilization and homing through inhibition of the HIF-1α/SDF-1 pathway. This represents a novel molecular mechanism for PPARα's antiangiogenic effects.
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Affiliation(s)
- Zhongxiao Wang
- Department of Ophthalmology, Shanghai First People's Hospital Affiliated with Shanghai Jiaotong University, Shanghai, China Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
| | - Elizabeth Moran
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
| | - Lexi Ding
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States Department of Ophthalmology, Xiangya Hospital, Central South University, Changsha, China
| | - Rui Cheng
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
| | - Xun Xu
- Department of Ophthalmology, Shanghai First People's Hospital Affiliated with Shanghai Jiaotong University, Shanghai, China
| | - Jian-xing Ma
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
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Li XQ, Ouyang ZG, Zhang SH, Liu H, Shang Y, Li Y, Zhen YS. Synergistic inhibition of angiogenesis and glioma cell-induced angiogenesis by the combination of temozolomide and enediyne antibiotic lidamycin. Cancer Biol Ther 2014; 15:398-408. [PMID: 24424202 DOI: 10.4161/cbt.27626] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Present work mainly evaluated the inhibitory effects of lidamycin (LDM), an enediyne antibiotic, on angiogenesis or glioma-induced angiogenesis in vitro and in vivo, especially its synergistic anti-angiogenesis with temozolomide (TMZ). LDM alone efficiently inhibited proliferations and induced apoptosis of rat brain microvessel endothelial cells (rBMEC). LDM also interrupted the tube formation of rat brain microvessel endothelial cells (rBMEC) and rat aortic ring spreading. The blockade of rBMEC invasion and C6 cell-induced rBMEC migration by LDM was associated with decrease of VEGF secretion in a co-culture system. TMZ dramatically potentiated the effects of LDM on anti-proliferation, apoptosis induction, and synergistically inhibited angiogenesis events. As determined by western blot and ELISA, the interaction of tumor cells and the rBMEC was markedly interrupted by LDM plus TMZ with synergistic regulations of VEGF induced angiogenesis signal pathway, tumor cell invasion/migration, and apoptosis signal pathway. Immunofluorohistochemistry of CD31 and VEGF showed that LDM plus TMZ resulted in synergistic decrease of microvessel density (MVD) and VEGF expression in human glioma U87 cell subcutaneous xenograft. This study indicates that the high efficacy of LDM and the synergistic effects of LDM plus TMZ against glioma are mediated, at least in part, by the potentiated anti-angiogenesis.
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Affiliation(s)
- Xing-Qi Li
- College of Life Science & Technology; Heilongjiang Bayi Agricultural University; Daqing, PR China; Institute of Medicinal Biotechnology; Chinese Academy of Medical Sciences & Peking Union Medical College; Beijing, PR China
| | - Zhi-Gang Ouyang
- Institute of Medicinal Biotechnology; Chinese Academy of Medical Sciences & Peking Union Medical College; Beijing, PR China
| | - Sheng-Hua Zhang
- Institute of Medicinal Biotechnology; Chinese Academy of Medical Sciences & Peking Union Medical College; Beijing, PR China
| | - Hong Liu
- Institute of Medicinal Biotechnology; Chinese Academy of Medical Sciences & Peking Union Medical College; Beijing, PR China
| | - Yue Shang
- Institute of Medicinal Biotechnology; Chinese Academy of Medical Sciences & Peking Union Medical College; Beijing, PR China
| | - Yi Li
- Institute of Medicinal Biotechnology; Chinese Academy of Medical Sciences & Peking Union Medical College; Beijing, PR China
| | - Yong-Su Zhen
- Institute of Medicinal Biotechnology; Chinese Academy of Medical Sciences & Peking Union Medical College; Beijing, PR China
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Avraham HK, Jiang S, Fu Y, Nakshatri H, Ovadia H, Avraham S. Angiopoietin-2 mediates blood-brain barrier impairment and colonization of triple-negative breast cancer cells in brain. J Pathol 2014; 232:369-81. [DOI: 10.1002/path.4304] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Revised: 11/06/2013] [Accepted: 11/11/2013] [Indexed: 12/19/2022]
Affiliation(s)
- Hava Karsenty Avraham
- Division of Experimental Medicine; Beth Israel Deaconess Medical Center and Harvard Medical School; Boston MA USA
| | - Shuxian Jiang
- Division of Experimental Medicine; Beth Israel Deaconess Medical Center and Harvard Medical School; Boston MA USA
| | - Yigong Fu
- Division of Experimental Medicine; Beth Israel Deaconess Medical Center and Harvard Medical School; Boston MA USA
| | - Harikrishna Nakshatri
- Departments of Surgery, and Biochemistry and Molecular Biology; Indiana University School of Medicine; Indianapolis IN USA
| | - Haim Ovadia
- Department of Neurology; Hadassah University Hospital; Jerusalem Israel
| | - Shalom Avraham
- Division of Experimental Medicine; Beth Israel Deaconess Medical Center and Harvard Medical School; Boston MA USA
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Abdelsaid MA, Matragoon S, El-Remessy AB. Thioredoxin-interacting protein expression is required for VEGF-mediated angiogenic signal in endothelial cells. Antioxid Redox Signal 2013; 19:2199-212. [PMID: 23718729 PMCID: PMC3869450 DOI: 10.1089/ars.2012.4761] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
AIMS Thioredoxin-interacting protein (TXNIP) contributes to cellular redox-state homeostasis via binding and inhibiting thioredoxin (TRX). Increasing evidence suggests that cellular redox homeostasis regulates vascular endothelial growth factor (VEGF)-mediated signaling. This study aims to examine the redox-dependant role of TXNIP in regulating VEGF-mediated S-glutathionylation and angiogenic signaling. TXNIP-knockout mice (TKO) or wild-type (WT) treated with the reduced glutathione (GSH)-precursor, N-acetyl cysteine (WT-NAC, 500 mg/kg) were compared to WT using hypoxia-induced neovascularization model. RESULTS In response to hypoxia, retinas from TKO and WT-NAC mice showed significant decreases in reparative revascularization and pathological neovascularization with similar VEGF expression compared with WT. VEGF failed to stimulate vascular sprouting from aortic rings of TKO compared to WT mice. TKO mice or WT+NAC experienced reductive stress as indicated by twofold increase in TRX reductase activity and fourfold increase in reduced-GSH levels compared with WT. In human microvascular endothelial (HME) cells, VEGF stimulated co-precipitation between vascular endothelial growth factor receptor 2 (VEGFR2) with low molecular weight protein tyrosine phosphatase (LMW-PTP). Silencing TXNIP expression blunted VEGF-induced oxidation of GSH and S-glutathionylation of the LMW-PTP in HME cells. These effects were associated with impaired VEGFR2 phosphorylation that culminated in inhibiting cell migration and tube formation. Overexpression of TXNIP restored VEGFR2 phosphorylation and cell migration in TKO-endothelial cells. INNOVATION TXNIP expression is required for VEGF-mediated VEGFR2 activation and angiogenic response in vivo and in vitro. TXNIP expression regulates VEGFR-2 phosphorylation via S-glutathionylation of LMW-PTP in endothelial cells. CONCLUSION Our results provide novel mechanistic insight into modulating TXNIP expression as a potential therapeutic target in diseases characterized by aberrant angiogenesis.
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Affiliation(s)
- Mohammed A Abdelsaid
- 1 Program in Clinical and Experimental Therapeutics, College of Pharmacy, University of Georgia , Augusta, Georgia
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A simple method for isolating and culturing the rat brain microvascular endothelial cells. Microvasc Res 2013; 90:199-205. [DOI: 10.1016/j.mvr.2013.08.004] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Revised: 06/12/2013] [Accepted: 08/14/2013] [Indexed: 02/05/2023]
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50
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Amyloid β suppresses protein C activation through inhibition of the endothelial protein C receptor (EPCR). J Mol Neurosci 2013; 52:117-23. [PMID: 24072481 DOI: 10.1007/s12031-013-0123-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Accepted: 09/12/2013] [Indexed: 12/26/2022]
Abstract
Alzheimer's disease (AD) is known to be associated with microcirculatory injury, capillary blockage, and disruption of the blood-brain barrier. Endothelial dysfunction has also been reported to be associated with AD, but the underlying mechanisms remain to be elucidated. Endothelial protein C receptor (EPCR) is an N-glycosylated type I membrane protein that enhances the activation of protein C. However, the effects of EPCR and protein C in AD are still unknown. In this study, we found that the expression of EPCR was reduced in the brains of β-amyloid precursor protein overexpressing Tg2576 transgenic mice at both the mRNA level and the protein level. However, levels of thrombomodulin (TM) did not undergo any changes. An in vitro study displayed that β-amyloid (Aβ) treatment led to suppression of EPCR along with reduction of protein C activation in mouse primary endothelial cells. Further study revealed that the induction of the c-Jun N-terminal kinase (JNK)/c-Jun pathway plays a causal role in the inhibitory effects of Aβ1-42 on the expression of EPCR. As a transcriptional factor, c-Jun was able to transinactivate the EPCR promoter. Finally, we found that c-Jun silencing or the use of a JNK inhibitor could attenuate the effects of Aβ1-42 in the activation of protein C.
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