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Jazaeri SZ, Taghizadeh G, Babaei JF, Goudarzi S, Saadatmand P, Joghataei MT, Khanahmadi Z. Aquaporin 4 beyond a water channel; participation in motor, sensory, cognitive and psychological performances, a comprehensive review. Physiol Behav 2023; 271:114353. [PMID: 37714320 DOI: 10.1016/j.physbeh.2023.114353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 08/15/2023] [Accepted: 09/13/2023] [Indexed: 09/17/2023]
Abstract
Aquaporin 4 (AQP4) is a protein highly expressed in the central nervous system (CNS) and peripheral nervous system (PNS) as well as various other organs, whose different sites of action indicate its importance in various functions. AQP4 has a variety of essential roles beyond water homeostasis. In this article, we have for the first time summarized different roles of AQP4 in motor and sensory functions, besides cognitive and psychological performances, and most importantly, possible physiological mechanisms by which AQP4 can exert its effects. Furthermore, we demonstrated that AQP4 participates in pathology of different neurological disorders, various effects depending on the disease type. Since neurological diseases involve a spectrum of dysfunctions and due to the difficulty of obtaining a treatment that can simultaneously affect these deficits, it is therefore suggested that future studies consider the role of this protein in different functional impairments related to neurological disorders simultaneously or separately by targeting AQP4 expression and/or polarity modulation.
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Affiliation(s)
- Seyede Zohreh Jazaeri
- Department of Neuroscience, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran, Iran; Division of Neuroscience, Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Ghorban Taghizadeh
- Department of Occupational Therapy, School of Rehabilitation Sciences, Iran University of Medical Sciences, Tehran, Iran.
| | - Javad Fahanik Babaei
- Electrophysiology Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Sepideh Goudarzi
- Experimental Medicine Research Center, Tehran University of medical Sciences, Tehran, Iran
| | - Pegah Saadatmand
- Department of Medical Physics, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Mohammad Taghi Joghataei
- Department of Neuroscience, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran, Iran; Division of Neuroscience, Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran; Department of Anatomy, School of Medicine, Iran University of Medical Sciences, Tehran, Iran; Department of Innovation in Medical Education, Faculty of Medicine, Ottawa University, Ottawa, Canada.
| | - Zohreh Khanahmadi
- Department of Occupational Therapy, School of Rehabilitation Services, Isfahan University of Medical Sciences, Isfahan, Iran
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Mohamadi Y, Borhani-Haghighi M. TGN020 application against aquaporin 4 improved multiple sclerosis by inhibiting astrocytes, microglia, and NLRP3 inflammasome in a cuprizone mouse model. J Chem Neuroanat 2023; 132:102306. [PMID: 37394105 DOI: 10.1016/j.jchemneu.2023.102306] [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] [Received: 02/24/2023] [Revised: 06/20/2023] [Accepted: 06/30/2023] [Indexed: 07/04/2023]
Abstract
In multiple sclerosis (MS), activation of the astrocytes and microglia induces a cascading inflammatory response. Overexpression of the aquaporin 4 (AQP4) in the glia is a trigger for this reaction. This study aimed to block AQP4 by injecting TGN020 to alleviate the symptoms of MS. Total of 30 male mice were randomly divided into control (intact), cuprizone model of MS (fed with 0.2% cuprizone for 35 days), and TGN020-treated (received daily intraperitoneal injections of 200 mg/kg TGN020 with cuprizone intake) groups. Astrogliosis, M1-M2 microglia polarization, NLRP3 inflammasome activation, and demyelination were investigated in the corpus callosum by immunohistochemistry, real-time PCR, western blot, and luxol fast blue staining. The Rotarod test was performed for a behavior assessment. AQP4 inhibition caused a significant decrease in the expression of the astrocyte-specific marker, GFAP. It also changed the microglia polarization from M1 to M2 indicated by a significant downregulation of iNOS, CD86, MHC-ІІ, and upregulation of arginase1, CD206, and TREM-2. In addition, western blot data showed a significant decrease in the NLRP3, caspase1, and IL-1b proteins in the treatment group, which indicated inflammasome inactivation. The molecular changes following the TGN020 injection resulted in remyelination and motor recovery enhancement in the treatment group. In conclusion, the results draw the attention to the role of AQP4 in the cuprizone model of MS.
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Affiliation(s)
- Yousef Mohamadi
- Department of Anatomy, School of Medicine, Ilam University of Medical Sciences, Ilam, Iran
| | - Maryam Borhani-Haghighi
- Department of Anatomy, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
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Toader C, Tataru CP, Florian IA, Covache-Busuioc RA, Dumitrascu DI, Glavan LA, Costin HP, Bratu BG, Ciurea AV. From Homeostasis to Pathology: Decoding the Multifaceted Impact of Aquaporins in the Central Nervous System. Int J Mol Sci 2023; 24:14340. [PMID: 37762642 PMCID: PMC10531540 DOI: 10.3390/ijms241814340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2023] [Revised: 09/15/2023] [Accepted: 09/18/2023] [Indexed: 09/29/2023] Open
Abstract
Aquaporins (AQPs), integral membrane proteins facilitating selective water and solute transport across cell membranes, have been the focus of extensive research over the past few decades. Particularly noteworthy is their role in maintaining cellular homeostasis and fluid balance in neural compartments, as dysregulated AQP expression is implicated in various degenerative and acute brain pathologies. This article provides an exhaustive review on the evolutionary history, molecular classification, and physiological relevance of aquaporins, emphasizing their significance in the central nervous system (CNS). The paper journeys through the early studies of water transport to the groundbreaking discovery of Aquaporin 1, charting the molecular intricacies that make AQPs unique. It delves into AQP distribution in mammalian systems, detailing their selective permeability through permeability assays. The article provides an in-depth exploration of AQP4 and AQP1 in the brain, examining their contribution to fluid homeostasis. Furthermore, it elucidates the interplay between AQPs and the glymphatic system, a critical framework for waste clearance and fluid balance in the brain. The dysregulation of AQP-mediated processes in this system hints at a strong association with neurodegenerative disorders such as Parkinson's Disease, idiopathic normal pressure hydrocephalus, and Alzheimer's Disease. This relationship is further explored in the context of acute cerebral events such as stroke and autoimmune conditions such as neuromyelitis optica (NMO). Moreover, the article scrutinizes AQPs at the intersection of oncology and neurology, exploring their role in tumorigenesis, cell migration, invasiveness, and angiogenesis. Lastly, the article outlines emerging aquaporin-targeted therapies, offering a glimpse into future directions in combatting CNS malignancies and neurodegenerative diseases.
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Affiliation(s)
- Corneliu Toader
- Department of Neurosurgery, “Carol Davila” University of Medicine and Pharmacy, 020021 Bucharest, Romania; (C.T.); (R.-A.C.-B.); (D.-I.D.); (L.A.G.); (H.P.C.); (B.-G.B.); (A.V.C.)
- Department of Vascular Neurosurgery, National Institute of Neurology and Neurovascular Diseases, 077160 Bucharest, Romania
| | - Calin Petru Tataru
- Department of Opthamology, “Carol Davila” University of Medicine and Pharmacy, 020021 Bucharest, Romania
- Central Military Emergency Hospital “Dr. Carol Davila”, 010825 Bucharest, Romania
| | - Ioan-Alexandru Florian
- Department of Neurosciences, “Iuliu Hatieganu” University of Medicine and Pharmacy, 400012 Cluj-Napoca, Romania
| | - Razvan-Adrian Covache-Busuioc
- Department of Neurosurgery, “Carol Davila” University of Medicine and Pharmacy, 020021 Bucharest, Romania; (C.T.); (R.-A.C.-B.); (D.-I.D.); (L.A.G.); (H.P.C.); (B.-G.B.); (A.V.C.)
| | - David-Ioan Dumitrascu
- Department of Neurosurgery, “Carol Davila” University of Medicine and Pharmacy, 020021 Bucharest, Romania; (C.T.); (R.-A.C.-B.); (D.-I.D.); (L.A.G.); (H.P.C.); (B.-G.B.); (A.V.C.)
| | - Luca Andrei Glavan
- Department of Neurosurgery, “Carol Davila” University of Medicine and Pharmacy, 020021 Bucharest, Romania; (C.T.); (R.-A.C.-B.); (D.-I.D.); (L.A.G.); (H.P.C.); (B.-G.B.); (A.V.C.)
| | - Horia Petre Costin
- Department of Neurosurgery, “Carol Davila” University of Medicine and Pharmacy, 020021 Bucharest, Romania; (C.T.); (R.-A.C.-B.); (D.-I.D.); (L.A.G.); (H.P.C.); (B.-G.B.); (A.V.C.)
| | - Bogdan-Gabriel Bratu
- Department of Neurosurgery, “Carol Davila” University of Medicine and Pharmacy, 020021 Bucharest, Romania; (C.T.); (R.-A.C.-B.); (D.-I.D.); (L.A.G.); (H.P.C.); (B.-G.B.); (A.V.C.)
| | - Alexandru Vlad Ciurea
- Department of Neurosurgery, “Carol Davila” University of Medicine and Pharmacy, 020021 Bucharest, Romania; (C.T.); (R.-A.C.-B.); (D.-I.D.); (L.A.G.); (H.P.C.); (B.-G.B.); (A.V.C.)
- Neurosurgery Department, Sanador Clinical Hospital, 010991 Bucharest, Romania
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Keledjian K, Makar T, Zhang C, Zhang J, Shim B, Davis H, Bryant J, Gerzanich V, Simard JM, Zhao RY. Correlation of HIV-Induced Neuroinflammation and Synaptopathy with Impairment of Learning and Memory in Mice with HAND. J Clin Med 2023; 12:5169. [PMID: 37629211 PMCID: PMC10455390 DOI: 10.3390/jcm12165169] [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: 05/11/2023] [Revised: 08/01/2023] [Accepted: 08/06/2023] [Indexed: 08/27/2023] Open
Abstract
Over 38 million people worldwide are living with HIV/AIDS, and more than half of them are affected by HIV-associated neurocognitive disorders (HAND). Such disorders are characterized by chronic neuroinflammation, neurotoxicity, and central nervous system deterioration, which lead to short- or long-term memory loss, cognitive impairment, and motor skill deficits that may show gender disparities. However, the underlying mechanisms remain unclear. Our previous study suggested that HIV-1 infection and viral protein R (Vpr) upregulate the SUR1-TRPM4 channel associated with neuroinflammation, which may contribute to HAND. The present study aimed to explore this relationship in a mouse model of HAND. This study employed the HIV transgenic Tg26 mouse model, comparing Tg26 mice with wildtype mice in various cognitive behavioral and memory tests, including locomotor activity tests, recognition memory tests, and spatial learning and memory tests. The study found that Tg26 mice exhibited impaired cognitive skills and reduced learning abilities compared to wildtype mice, particularly in spatial memory. Interestingly, male Tg26 mice displayed significant differences in spatial memory losses (p < 0.001), while no significant differences were identified in female mice. Consistent with our early results, SUR1-TRPM4 channels were upregulated in Tg26 mice along with glial fibrillary acidic protein (GFAP) and aquaporin 4 (AQP4), consistent with reactive astrocytosis and neuroinflammation. Corresponding reductions in neurosynaptic responses, as indicated by downregulation of Synapsin-1 (SYN1) and Synaptophysin (SYP), suggested synaptopathy as a possible mechanism underlying cognitive and motor skill deficits. In conclusion, our study suggests a possible relationship between SUR1-TRPM4-mediated neuroinflammation and synaptopathy with impairments of learning and memory in mice with HAND. These findings could help to develop new therapeutic strategies for individuals living with HAND.
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Affiliation(s)
- Kaspar Keledjian
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (K.K.); (T.M.); (B.S.); (V.G.)
| | - Tapas Makar
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (K.K.); (T.M.); (B.S.); (V.G.)
| | - Chenyu Zhang
- Department of Pathology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (C.Z.); (J.Z.)
| | - Jiantao Zhang
- Department of Pathology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (C.Z.); (J.Z.)
| | - Bosung Shim
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (K.K.); (T.M.); (B.S.); (V.G.)
| | - Harry Davis
- Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (H.D.); (J.B.)
| | - Joseph Bryant
- Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (H.D.); (J.B.)
| | - Volodymyr Gerzanich
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (K.K.); (T.M.); (B.S.); (V.G.)
| | - J. Marc Simard
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (K.K.); (T.M.); (B.S.); (V.G.)
- Department of Pathology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (C.Z.); (J.Z.)
- Surgical Care Clinical Center, VA Maryland Health Care System, Baltimore, MD 21201, USA
| | - Richard Y. Zhao
- Department of Pathology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (C.Z.); (J.Z.)
- Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; (H.D.); (J.B.)
- Department of Microbiology-Immunology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
- Institute of Global Health, University of Maryland School of Medicine, Baltimore, MD 21201, USA
- Research & Development Service, VA Maryland Health Care System, Baltimore, MD 21201, USA
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Silverglate B, Gao X, Lee HP, Maliha P, Grossberg GT. The aquaporin-4 water channel and updates on its potential as a drug target for Alzheimer's disease. Expert Opin Ther Targets 2023; 27:523-530. [PMID: 37475487 DOI: 10.1080/14728222.2023.2240017] [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] [Received: 04/24/2023] [Accepted: 07/19/2023] [Indexed: 07/22/2023]
Abstract
INTRODUCTION Although there are several FDA-approved treatments for Alzheimer's disease (AD), only recently have disease-modifying therapies received approval for use in patients. In this narrative review, we examine the history of aquaporin-4 (AQP4) as a therapeutic target for NMOSD (neuromyelitis optica spectrum disorder) and as a potential therapeutic target for AD. AREAS COVERED We review the basic science and discovery of AQP4, a transmembrane water-channel essential to regulating water balance in the central nervous system (CNS). We also review the pathogenesis of NMOSD, an autoimmune disease characterized by the destruction of cells that express AQP4. Then, we review how AQP4 is likely involved in the pathogenesis of Alzheimer's disease (AD). Finally, we discuss future challenges with drug design that would modulate AQP4 to potentially slow AD development. The literature search for this article consisted of searching Google Scholar and PubMed for permutations of the keywords 'Alzheimer's disease,' 'aquaporin-4,' 'neuromyelitis optica,' and their abbreviations. EXPERT OPINION We place research into AQP4 into context with other recent developments in AD research. A major difficulty with drug development for Alzheimer's is the lack of strategies to cleanly target the early pathogenesis of the disease. Targeting AQP4 may provide such a strategy.
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Affiliation(s)
- Bret Silverglate
- Division of Geriatric Psychiatry, St. Louis University School of Medicine, St. Louis, Missouri, USA
| | - Xiaoyi Gao
- Division of Geriatric Psychiatry, St. Louis University School of Medicine, St. Louis, Missouri, USA
| | - Hannah P Lee
- Division of Geriatric Psychiatry, St. Louis University School of Medicine, St. Louis, Missouri, USA
| | - Peter Maliha
- Carolyn Wells-Peterson Geriatric Psychiatry Research Fellow, St. Louis University School of Medicine, St. Louis, Missouri, USA
| | - George T Grossberg
- Division of Geriatric Psychiatry, St. Louis University School of Medicine, St. Louis, Missouri, USA
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Paez-Gonzalez P, Lopez-de-San-Sebastian J, Ceron-Funez R, Jimenez AJ, Rodríguez-Perez LM. Therapeutic strategies to recover ependymal barrier after inflammatory damage: relevance for recovering neurogenesis during development. Front Neurosci 2023; 17:1204197. [PMID: 37397456 PMCID: PMC10308384 DOI: 10.3389/fnins.2023.1204197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Accepted: 05/22/2023] [Indexed: 07/04/2023] Open
Abstract
The epithelium covering the surfaces of the cerebral ventricular system is known as the ependyma, and is essential for maintaining the physical and functional integrity of the central nervous system. Additionally, the ependyma plays an essential role in neurogenesis, neuroinflammatory modulation and neurodegenerative diseases. Ependyma barrier is severely affected by perinatal hemorrhages and infections that cross the blood brain barrier. The recovery and regeneration of ependyma after damage are key to stabilizing neuroinflammatory and neurodegenerative processes that are critical during early postnatal ages. Unfortunately, there are no effective therapies to regenerate this tissue in human patients. Here, the roles of the ependymal barrier in the context of neurogenesis and homeostasis are reviewed, and future research lines for development of actual therapeutic strategies are discussed.
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Affiliation(s)
- Patricia Paez-Gonzalez
- Department of Cell Biology, Genetics and Physiology, University of Malaga, Málaga, Spain
- Instituto de Investigación Biomédica de Málaga y Plataforma en Nanomedicina-IBIMA Plataforma BIONAND, Málaga, Spain
| | | | - Raquel Ceron-Funez
- Department of Cell Biology, Genetics and Physiology, University of Malaga, Málaga, Spain
| | - Antonio J. Jimenez
- Instituto de Investigación Biomédica de Málaga y Plataforma en Nanomedicina-IBIMA Plataforma BIONAND, Málaga, Spain
| | - Luis Manuel Rodríguez-Perez
- Department of Cell Biology, Genetics and Physiology, University of Malaga, Málaga, Spain
- Instituto de Investigación Biomédica de Málaga y Plataforma en Nanomedicina-IBIMA Plataforma BIONAND, Málaga, Spain
- Department of Human Physiology, Human Histology, Pathological Anatomy and Sports, University of Malaga, Málaga, Spain
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Czuba-Pakuła E, Głowiński S, Wójcik S, Lietzau G, Zabielska-Kaczorowska M, Kowiański P. The extent of damage to the blood-brain barrier in the hypercholesterolemic LDLR -/-/Apo E -/- double knockout mice depends on the animal's age, duration of pathology and brain area. Mol Cell Neurosci 2023; 125:103860. [PMID: 37182573 DOI: 10.1016/j.mcn.2023.103860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 04/30/2023] [Accepted: 05/08/2023] [Indexed: 05/16/2023] Open
Abstract
One of the effects of hypercholesterolemia (Hch) exerted on the central nervous system (CNS) is damage to the blood-brain barrier (BBB). Increased permeability of BBB results from structural changes in the vascular wall, loss of the tight junctions and barrier function, as well as alterations in the concentration of proteins located in the layers of the vascular wall. These changes occur in the course of metabolic and neurodegenerative diseases. The important role in the course of these processes is attributed to agrin, matrix metalloproteinase-9, and aquaporin-4. In this study, we aimed to determine: 1) the extent of Hch-induced damage to the BBB during maturation, and 2) the distribution of the above-mentioned markers in the vascular wall. Immunohistochemical staining and confocal microscopy were used for vascular wall protein assessment. The size of BBB damage was studied based on perivascular leakage of fluorescently labeled dextran. Three- and twelve-month-old male LDLR-/-/Apo E-/- double knockout mice (EX) developing Hch were used in the study. Age-matched male wild-type (WT) C57BL/6 mice were used as a control group. Differences in the concentration of studied markers coexisted with BBB disintegration, especially in younger mice. A relationship between the maturation of the vascular system and reduction of the BBB damage was also observed. We conclude that the extent of BBB permeability depends on animal age, duration of Hch, and brain region. These may explain different susceptibility of various brain areas to Hch, and different presentation of this pathology depending on age and its duration.
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Affiliation(s)
- Ewelina Czuba-Pakuła
- Division of Anatomy and Neurobiology, Faculty of Medicine, Medical University of Gdańsk, Dębinki 1, 80-211 Gdańsk, Poland.
| | - Sebastian Głowiński
- Institute of Health Sciences, Pomeranian University in Słupsk, Bohaterów Westerplatte 64, 76-200 Słupsk, Poland.
| | - Sławomir Wójcik
- Division of Anatomy and Neurobiology, Faculty of Medicine, Medical University of Gdańsk, Dębinki 1, 80-211 Gdańsk, Poland.
| | - Grażyna Lietzau
- Division of Anatomy and Neurobiology, Faculty of Medicine, Medical University of Gdańsk, Dębinki 1, 80-211 Gdańsk, Poland.
| | - Magdalena Zabielska-Kaczorowska
- Department of Physiology, Medical University of Gdańsk, 1 Dębinki Str., 80-211 Gdańsk, Poland; Department of Biochemistry, Medical University of Gdańsk, 1 Dębinki Str., 80-211 Gdańsk, Poland.
| | - Przemysław Kowiański
- Division of Anatomy and Neurobiology, Faculty of Medicine, Medical University of Gdańsk, Dębinki 1, 80-211 Gdańsk, Poland; Institute of Health Sciences, Pomeranian University in Słupsk, Bohaterów Westerplatte 64, 76-200 Słupsk, Poland.
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Kawauchi S, Mizoguchi T, Horibe S, Tanaka T, Sasaki N, Ikeda K, Emoto N, Hirata KI, Rikitake Y. Gliovascular interface abnormality in mice with endothelial cell senescence. Glia 2023; 71:467-479. [PMID: 36286494 DOI: 10.1002/glia.24287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Revised: 10/06/2022] [Accepted: 10/10/2022] [Indexed: 12/24/2022]
Abstract
In the brain, neurons, glial cells, vascular endothelial cells (ECs), and mural cells form a functional structure referred to as the neurovascular unit (NVU). The functions of the NVU become impaired with aging. To gain insight into the mechanism underlying the aging-related changes in the NVU, we characterized in the present study the gliovascular interface in transgenic mice expressing a dominant-negative form of the telomeric repeat-binding factor 2 (TERF2) specifically in ECs using the Tie2 promoter. In these transgenic mice, senescence occurred in the cerebral ECs and was accompanied by upregulation of the mRNAs of proinflammatory cell adhesion molecules and cytokines. It is noteworthy that in the deep layers of the cerebral cortex, astrocytes exhibited an increase in the signals for S100β as well as a decrease in the polarization of the water channel aquaporin-4 (AQP4) to the perivascular endfeet of the astrocytes. Mechanistically, the perivascular localization of dystroglycan and its ligand, laminin α2, was decreased, and their localization correlated well with the perivascular localization of AQP4, which supports the notion that their interaction regulates the perivascular localization of AQP4. The diminished perivascular localization of laminin α2 may be attributed to its proteolytic degradation by the matrix metalloproteinase-2 released by senescent ECs. Pericyte coverage was increased and negatively correlated with the decrease in the perivascular localization of AQP4. We propose that aging-related changes in ECs induce a mild morphological alteration of astrocytes and affect the localization of AQP4 at the gliovascular interface.
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Affiliation(s)
- Shoji Kawauchi
- Comprehensive Education and Research Center, Kobe Pharmaceutical University, Kobe, Japan
| | - Taiji Mizoguchi
- Laboratory of Medical Pharmaceutics, Kobe Pharmaceutical University, Kobe, Japan
| | - Sayo Horibe
- Laboratory of Medical Pharmaceutics, Kobe Pharmaceutical University, Kobe, Japan
| | - Toru Tanaka
- Laboratory of Medical Pharmaceutics, Kobe Pharmaceutical University, Kobe, Japan
| | - Naoto Sasaki
- Laboratory of Medical Pharmaceutics, Kobe Pharmaceutical University, Kobe, Japan
| | - Koji Ikeda
- Laboratory of Clinical Pharmaceutical Science, Kobe Pharmaceutical University, Kobe, Japan
| | - Noriaki Emoto
- Laboratory of Clinical Pharmaceutical Science, Kobe Pharmaceutical University, Kobe, Japan
| | - Ken-Ichi Hirata
- Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Yoshiyuki Rikitake
- Laboratory of Medical Pharmaceutics, Kobe Pharmaceutical University, Kobe, Japan
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Archie SR, Al Shoyaib A, Cucullo L. Blood-Brain Barrier Dysfunction in CNS Disorders and Putative Therapeutic Targets: An Overview. Pharmaceutics 2021; 13:pharmaceutics13111779. [PMID: 34834200 PMCID: PMC8622070 DOI: 10.3390/pharmaceutics13111779] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 10/15/2021] [Accepted: 10/20/2021] [Indexed: 01/22/2023] Open
Abstract
The blood-brain barrier (BBB) is a fundamental component of the central nervous system (CNS). Its functional and structural integrity is vital to maintain the homeostasis of the brain microenvironment by controlling the passage of substances and regulating the trafficking of immune cells between the blood and the brain. The BBB is primarily composed of highly specialized microvascular endothelial cells. These cells’ special features and physiological properties are acquired and maintained through the concerted effort of hemodynamic and cellular cues from the surrounding environment. This complex multicellular system, comprising endothelial cells, astrocytes, pericytes, and neurons, is known as the neurovascular unit (NVU). The BBB strictly controls the transport of nutrients and metabolites into brain parenchyma through a tightly regulated transport system while limiting the access of potentially harmful substances via efflux transcytosis and metabolic mechanisms. Not surprisingly, a disruption of the BBB has been associated with the onset and/or progression of major neurological disorders. Although the association between disease and BBB disruption is clear, its nature is not always evident, specifically with regard to whether an impaired BBB function results from the pathological condition or whether the BBB damage is the primary pathogenic factor prodromal to the onset of the disease. In either case, repairing the barrier could be a viable option for treating and/or reducing the effects of CNS disorders. In this review, we describe the fundamental structure and function of the BBB in both healthy and altered/diseased conditions. Additionally, we provide an overview of the potential therapeutic targets that could be leveraged to restore the integrity of the BBB concomitant to the treatment of these brain disorders.
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Affiliation(s)
- Sabrina Rahman Archie
- Department of Pharmaceutical Sciences, Texas Tech University Health Sciences Center, Amarillo, TX 79106, USA; (S.R.A.); (A.A.S.)
| | - Abdullah Al Shoyaib
- Department of Pharmaceutical Sciences, Texas Tech University Health Sciences Center, Amarillo, TX 79106, USA; (S.R.A.); (A.A.S.)
| | - Luca Cucullo
- Department of Foundational Medical Studies, Oakland University William Beaumont School of Medicine, Rochester, MI 48309, USA
- Correspondence: ; Tel.: +1-248-370-3884; Fax: +1-248-370-4060
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Li B, Yuan H, Li H, Luo B, Yu X, Wang Y, Liu W. Mechanism of Aquaporin-4 Up-Regulation After Traumatic Brain Injury and Preventative Action of Astragalus Polysaccharides in Mice. J BIOMATER TISS ENG 2021. [DOI: 10.1166/jbt.2021.2502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Here, we aimed to clarify the anti-inflammatory function of Astragalus Polysaccharides (APS), a chemical compound derived from Astragalus membranaceus, and the action of AQP4 on brain injury. We hypothesized that APS could improve the traumatic brain injury (TBI) outcome via
inhibiting expression of AQP4 in astrocytes. The present study elucidated that AQP4 was up-regulated and was effectively blocked by APS in mice with severe controlled cortical impact (CCI). Pre-treatment with APS effectively inhibited the up-regulation of AQP4 and diminished the neurological
deficits in mice. Additionally, primary astrocytes treated with mechanically-injured astrocyte supernatant, to mimic TBI in vitro, showed a significant up-regulation in swelling. We confirmed various signal molecules (NF-ĸB, MAPKs, and ERK) to have a role in astrocyte
swelling, after activation in trauma, and to be involved in the up-regulation of AQP4. These signal molecules also significantly decreased with APS treatment. In conclusion, our study suggests that APS attenuated neurological deficits and brain edema by decreasing AQP4 up-regulation in astrocytes
following TBI in mice, via reducing NF-ĸB, MAPKs, and the ERK signal molecules.
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Affiliation(s)
- Bin Li
- Department of Neurosurgery, The People’s Hospital of Hanchuan, Xiaogan 431600, Hubei, PR China
| | - Honggang Yuan
- Department of Neurosurgery, The People’s Hospital of Hanchuan, Xiaogan 431600, Hubei, PR China
| | - Huibing Li
- Department of Neurosurgery, The People’s Hospital of Hanchuan, Xiaogan 431600, Hubei, PR China
| | - Baochang Luo
- Department of Neurosurgery, The People’s Hospital of Hanchuan, Xiaogan 431600, Hubei, PR China
| | - Xiaoping Yu
- Department of Neurosurgery, The People’s Hospital of Hanchuan, Xiaogan 431600, Hubei, PR China
| | - Yanhua Wang
- Department of Neurosurgery, The People’s Hospital of Hanchuan, Xiaogan 431600, Hubei, PR China
| | - Wen Liu
- Department of Neurosurgery, The People’s Hospital of Hanchuan, Xiaogan 431600, Hubei, PR China
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11
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Ghalami J, Baluchnejad Mojarad T, Mansouri M, Khamse S, Roghani M. Paeonol Protection Against Intrastriatal 6-Hydroxydopamine Rat Model of Parkinson's Disease. Basic Clin Neurosci 2021; 12:43-56. [PMID: 33995926 PMCID: PMC8114855 DOI: 10.32598/bcn.12.6.88.7] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 07/24/2018] [Accepted: 07/24/2019] [Indexed: 11/20/2022] Open
Abstract
Introduction: Parkinson’s Disease (PD) presentations comprise frequent movement disorders in the elderly with various symptoms consisting of motor and non-motor complications. Paeonol is a phenolic chemical agent that has shown antioxidant and anti-inflammatory effects in different disorders and promising effects on metabotropic glutamate receptors (mGluR)- and GABAA-mediated neurotransmission. In this research, we tried to show the neuroprotective potential of paeonol in rat PD model induced by intrastriatal 6-hydroxydopamine (6-OHDA). Methods: Rats with intrastriatal 6-OHDA lesioning received with paeonol at a dosage of 100 mg/kg/d for one week. In the end, some biomarkers of oxidative stress, apoptosis, and astrogliosis in nigral and striatal tissues were evaluated in addition to behavioral and Tyrosine Hydroxylase (TH) immunohistochemical analysis. Results: The obtained data showed that paeonol alleviates apomorphine-induced rotations and reduces the delay time to initiate and the total time in the narrow beam test. However, its beneficial behavioral effect vanished after intracerebroventricular administration of mGluR III or GABAA receptor antagonists. Moreover, paeonol significantly restored striatal malondialdehyde, tissue levels of reactive oxygen species, the activity of the protective and vital enzymes consisting of superoxide dismutase and catalase, Glial Fibrillary Acidic Protein (GFAP), DNA fragmentation, phosphor apoptosis signal-regulating kinase 1, and nigral aquaporin 4 with no significant and proper change of nitrite, interleukin-1β, inducible nitric oxide synthase, and angiotensin II. Additionally, paeonol prevented injury and reduced tyrosine hydroxylase-containing neurons in the midbrain nigral tissue. Conclusion: These obtained findings evidently designate neuroprotective property of paeonol in 6-OHDA murine model of PD that is exerted via easing of oxidative stress, apoptosis, astrogliosis, and its advantageous effect is to some extent mediated via mGluR III/GABAA pathway.
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Affiliation(s)
- Jamileh Ghalami
- Department of Physiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | | | - Monireh Mansouri
- Department of Physiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Safoura Khamse
- Department of Physiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Mehrdad Roghani
- Neurophysiology Research Center, Shahed University, Tehran, Iran
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12
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Kadry H, Noorani B, Cucullo L. A blood-brain barrier overview on structure, function, impairment, and biomarkers of integrity. Fluids Barriers CNS 2020; 17:69. [PMID: 33208141 PMCID: PMC7672931 DOI: 10.1186/s12987-020-00230-3] [Citation(s) in RCA: 533] [Impact Index Per Article: 133.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 11/07/2020] [Indexed: 02/07/2023] Open
Abstract
The blood–brain barrier is playing a critical role in controlling the influx and efflux of biological substances essential for the brain’s metabolic activity as well as neuronal function. Thus, the functional and structural integrity of the BBB is pivotal to maintain the homeostasis of the brain microenvironment. The different cells and structures contributing to developing this barrier are summarized along with the different functions that BBB plays at the brain–blood interface. We also explained the role of shear stress in maintaining BBB integrity. Furthermore, we elaborated on the clinical aspects that correlate between BBB disruption and different neurological and pathological conditions. Finally, we discussed several biomarkers that can help to assess the BBB permeability and integrity in-vitro or in-vivo and briefly explain their advantages and disadvantages.
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Affiliation(s)
- Hossam Kadry
- Department of Pharmaceutical Sciences, Jerry H. Hodge School of Pharmacy, Texas Tech University Health Sciences Center, 1300 S. Coulter Street, Amarillo, TX, 79106, USA
| | - Behnam Noorani
- Department of Pharmaceutical Sciences, Jerry H. Hodge School of Pharmacy, Texas Tech University Health Sciences Center, 1300 S. Coulter Street, Amarillo, TX, 79106, USA
| | - Luca Cucullo
- Dept. of Foundational Medical Studies, Oakland University William Beaumont School of Medicine, Office 415, Rochester, MI, 48309, USA.
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13
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Aquaporin-4 Expression during Toxic and Autoimmune Demyelination. Cells 2020; 9:cells9102187. [PMID: 32998402 PMCID: PMC7601078 DOI: 10.3390/cells9102187] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 09/18/2020] [Accepted: 09/25/2020] [Indexed: 12/28/2022] Open
Abstract
The water channel protein aquaporin-4 (AQP4) is required for a normal rate of water exchange across the blood–brain interface. Following the discovery that AQP4 is a possible autoantigen in neuromyelitis optica, the function of AQP4 in health and disease has become a research focus. While several studies have addressed the expression and function of AQP4 during inflammatory demyelination, relatively little is known about its expression during non-autoimmune-mediated myelin damage. In this study, we used the toxin-induced demyelination model cuprizone as well as a combination of metabolic and autoimmune myelin injury (i.e., Cup/EAE) to investigate AQP4 pathology. We show that during toxin-induced demyelination, diffuse AQP4 expression increases, while polarized AQP4 expression at the astrocyte endfeet decreases. The diffuse increased expression of AQP4 was verified in chronic-active multiple sclerosis lesions. Around inflammatory brain lesions, AQP4 expression dramatically decreased, especially at sites where peripheral immune cells penetrate the brain parenchyma. Humoral immune responses appear not to be involved in this process since no anti-AQP4 antibodies were detected in the serum of the experimental mice. We provide strong evidence that the diffuse increase in anti-AQP4 staining intensity is due to a metabolic injury to the brain, whereas the focal, perivascular loss of anti-AQP4 immunoreactivity is mediated by peripheral immune cells.
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14
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Kitchen P, Salman MM, Halsey AM, Clarke-Bland C, MacDonald JA, Ishida H, Vogel HJ, Almutiri S, Logan A, Kreida S, Al-Jubair T, Winkel Missel J, Gourdon P, Törnroth-Horsefield S, Conner MT, Ahmed Z, Conner AC, Bill RM. Targeting Aquaporin-4 Subcellular Localization to Treat Central Nervous System Edema. Cell 2020; 181:784-799.e19. [PMID: 32413299 PMCID: PMC7242911 DOI: 10.1016/j.cell.2020.03.037] [Citation(s) in RCA: 241] [Impact Index Per Article: 60.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 01/09/2020] [Accepted: 03/17/2020] [Indexed: 01/07/2023]
Abstract
Swelling of the brain or spinal cord (CNS edema) affects millions of people every year. All potential pharmacological interventions have failed in clinical trials, meaning that symptom management is the only treatment option. The water channel protein aquaporin-4 (AQP4) is expressed in astrocytes and mediates water flux across the blood-brain and blood-spinal cord barriers. Here we show that AQP4 cell-surface abundance increases in response to hypoxia-induced cell swelling in a calmodulin-dependent manner. Calmodulin directly binds the AQP4 carboxyl terminus, causing a specific conformational change and driving AQP4 cell-surface localization. Inhibition of calmodulin in a rat spinal cord injury model with the licensed drug trifluoperazine inhibited AQP4 localization to the blood-spinal cord barrier, ablated CNS edema, and led to accelerated functional recovery compared with untreated animals. We propose that targeting the mechanism of calmodulin-mediated cell-surface localization of AQP4 is a viable strategy for development of CNS edema therapies.
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Affiliation(s)
- Philip Kitchen
- School of Life & Health Sciences, Aston University, Aston Triangle, Birmingham B4 7ET, UK
| | - Mootaz M Salman
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA; Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA; Department of Pharmacology, College of Pharmacy, University of Mosul, Mosul 41002, Iraq
| | - Andrea M Halsey
- Neuroscience and Ophthalmology, Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Charlotte Clarke-Bland
- School of Life & Health Sciences, Aston University, Aston Triangle, Birmingham B4 7ET, UK
| | - Justin A MacDonald
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4Z6, Canada
| | - Hiroaki Ishida
- Department of Biological Sciences, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Hans J Vogel
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4Z6, Canada; Department of Biological Sciences, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Sharif Almutiri
- Neuroscience and Ophthalmology, Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK; Department of Clinical Laboratory Science, College of Applied Medical Science, Shaqra University, Shaqra, Saudi Arabia
| | - Ann Logan
- Neuroscience and Ophthalmology, Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Stefan Kreida
- Department of Biochemistry and Structural Biology, Lund University, PO Box 124, 221 00 Lund, Sweden
| | - Tamim Al-Jubair
- Department of Biochemistry and Structural Biology, Lund University, PO Box 124, 221 00 Lund, Sweden
| | - Julie Winkel Missel
- Department of Biomedical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Pontus Gourdon
- Department of Biomedical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark; Department of Experimental Medical Science, Lund University, PO Box 118, 221 00 Lund, Sweden
| | | | - Matthew T Conner
- School of Sciences, Research Institute in Healthcare Science, University of Wolverhampton, Wolverhampton WV1 1LY, UK
| | - Zubair Ahmed
- Neuroscience and Ophthalmology, Institute of Inflammation and Ageing, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
| | - Alex C Conner
- Institute of Clinical Sciences, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
| | - Roslyn M Bill
- School of Life & Health Sciences, Aston University, Aston Triangle, Birmingham B4 7ET, UK.
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15
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Domowicz MS, Chan WC, Claudio-Vázquez P, Henry JG, Ware CB, Andrade J, Dawson G, Schwartz NB. Global Brain Transcriptome Analysis of a Tpp1 Neuronal Ceroid Lipofuscinoses Mouse Model. ASN Neuro 2020; 11:1759091419843393. [PMID: 31003587 PMCID: PMC6475859 DOI: 10.1177/1759091419843393] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
In humans, homozygous mutations in the TPP1 gene results in loss
of tripeptidyl peptidase 1 (TPP1) enzymatic activity, leading to late infantile
neuronal ceroid lipofuscinoses disease. Using a mouse model that targets the
Tpp1 gene and recapitulates the pathology and clinical
features of the human disease, we analyzed end-stage (4 months) transcriptional
changes associated with lack of TPP1 activity. Using RNA sequencing technology,
Tpp1 expression changes in the forebrain/midbrain and
cerebellum of 4-month-old homozygotes were compared with strain-related
controls. Transcriptional changes were found in 510 and 1,550 gene transcripts
in forebrain/midbrain and cerebellum, respectively, from
Tpp1-deficient brain tissues when compared with age-matched
controls. Analysis of the differentially expressed genes using the Ingenuity™
pathway software, revealed increased neuroinflammation activity in microglia and
astrocytes that could lead to neuronal dysfunction, particularly in the
cerebellum. We also observed upregulation in the production of nitric oxide and
reactive oxygen species; activation of leukocyte extravasation signals and
complement pathways; and downregulation of major transcription factors involved
in control of circadian rhythm. Several of these expression changes were
confirmed by independent quantitative polymerase chain reaction and histological
analysis by mRNA in situ hybridization, which allowed for an
in-depth anatomical analysis of the pathology and provided independent
confirmation of at least two of the major networks affected in this model. The
identification of differentially expressed genes has revealed new lines of
investigation for this complex disorder that may lead to novel therapeutic
targets.
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Affiliation(s)
- Miriam S Domowicz
- 1 Department of Pediatrics, Biological Sciences Division, The University of Chicago, IL, USA
| | - Wen-Ching Chan
- 2 Center for Research Informatics, Biological Sciences Division, The University of Chicago, IL, USA
| | | | - Judith G Henry
- 1 Department of Pediatrics, Biological Sciences Division, The University of Chicago, IL, USA
| | - Christopher B Ware
- 1 Department of Pediatrics, Biological Sciences Division, The University of Chicago, IL, USA
| | - Jorge Andrade
- 2 Center for Research Informatics, Biological Sciences Division, The University of Chicago, IL, USA
| | - Glyn Dawson
- 1 Department of Pediatrics, Biological Sciences Division, The University of Chicago, IL, USA
| | - Nancy B Schwartz
- 1 Department of Pediatrics, Biological Sciences Division, The University of Chicago, IL, USA.,3 Department of Biochemistry and Molecular Biology, Biological Sciences Division, The University of Chicago, IL, USA
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16
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Chmelova M, Sucha P, Bochin M, Vorisek I, Pivonkova H, Hermanova Z, Anderova M, Vargova L. The role of aquaporin-4 and transient receptor potential vaniloid isoform 4 channels in the development of cytotoxic edema and associated extracellular diffusion parameter changes. Eur J Neurosci 2019; 50:1685-1699. [PMID: 30633415 DOI: 10.1111/ejn.14338] [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: 06/21/2018] [Revised: 12/27/2018] [Accepted: 01/04/2019] [Indexed: 11/30/2022]
Abstract
The proper function of the nervous system is dependent on the balance of ions and water between the intracellular and extracellular space (ECS). It has been suggested that the interaction of aquaporin-4 (AQP4) and the transient receptor potential vaniloid isoform 4 (TRPV4) channels play a role in water balance and cell volume regulation, and indirectly, of the ECS volume. Using the real-time iontophoretic method, we studied the changes of the ECS diffusion parameters: ECS volume fraction α (α = ECS volume fraction/total tissue volume) and tortuosity λ (λ2 = free/apparent diffusion coefficient) in mice with a genetic deficiency of AQP4 or TRPV4 channels, and in control animals. The used models of cytotoxic edema included: mild and severe hypotonic stress or oxygen-glucose deprivation (OGD) in situ and terminal ischemia/anoxia in vivo. This study shows that an AQP4 or TRPV4 deficit slows down the ECS volume shrinkage during severe ischemia in vivo. We further demonstrate that a TRPV4 deficit slows down the velocity and attenuates an extent of the ECS volume decrease during OGD treatment in situ. However, in any of the cytotoxic edema models in situ (OGD, mild or severe hypotonic stress), we did not detect any alterations in the cell swelling or volume regulation caused by AQP4 deficiency. Overall, our results indicate that the AQP4 and TRPV4 channels may play a crucial role in severe pathological states associated with their overexpression and enhanced cell swelling. However, detailed interplay between AQP4 and TRPV4 channels requires further studies and additional research.
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Affiliation(s)
- Martina Chmelova
- Department of Neuroscience, 2nd Faculty of Medicine, Charles University, Prague, Czech Republic.,Department of Cellular Neurophysiology, Institute of Experimental Medicine of the CAS, Prague, Czech Republic
| | - Petra Sucha
- Department of Neuroscience, 2nd Faculty of Medicine, Charles University, Prague, Czech Republic.,Department of Cellular Neurophysiology, Institute of Experimental Medicine of the CAS, Prague, Czech Republic
| | - Marcel Bochin
- Department of Neuroscience, 2nd Faculty of Medicine, Charles University, Prague, Czech Republic.,Department of Cellular Neurophysiology, Institute of Experimental Medicine of the CAS, Prague, Czech Republic
| | - Ivan Vorisek
- Department of Cellular Neurophysiology, Institute of Experimental Medicine of the CAS, Prague, Czech Republic
| | - Helena Pivonkova
- Department of Cellular Neurophysiology, Institute of Experimental Medicine of the CAS, Prague, Czech Republic
| | - Zuzana Hermanova
- Department of Cellular Neurophysiology, Institute of Experimental Medicine of the CAS, Prague, Czech Republic
| | - Miroslava Anderova
- Department of Neuroscience, 2nd Faculty of Medicine, Charles University, Prague, Czech Republic.,Department of Cellular Neurophysiology, Institute of Experimental Medicine of the CAS, Prague, Czech Republic
| | - Lydia Vargova
- Department of Neuroscience, 2nd Faculty of Medicine, Charles University, Prague, Czech Republic.,Department of Cellular Neurophysiology, Institute of Experimental Medicine of the CAS, Prague, Czech Republic
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17
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Zhu X, Fréchou M, Schumacher M, Guennoun R. Cerebroprotection by progesterone following ischemic stroke: Multiple effects and role of the neural progesterone receptors. J Steroid Biochem Mol Biol 2019; 185:90-102. [PMID: 30031789 DOI: 10.1016/j.jsbmb.2018.07.014] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Revised: 07/17/2018] [Accepted: 07/19/2018] [Indexed: 12/21/2022]
Abstract
Treatment with progesterone limits brain damage after stroke. However, the cellular bases of the cerebroprotective effects of progesterone are not well documented. The aims of this study were to determine neural cells and functions that are affected by progesterone treatment and the role of neural progesterone receptors (PR) after stroke. Adult male PRNesCre mice, selectively lacking PR in the central nervous system, and their control PRloxP/loxP littermates were subjected to transient ischemia by middle cerebral artery occlusion (MCAO) for 30 min. Mice received either progesterone (8 mg/kg) or vehicle at 1-, 6- and 24- hrs post-MCAO and outcomes were analyzed at 48 h post-MCAO. In PRloxP/loxP mice, progesterone exerted multiple effects on different neural cell types, improved motor functional outcomes and reduced total infarct volumes. In the peri-infarct, progesterone increased the density of neurons (NeuN+ cells), of cells of the oligodendroglial lineage (Olig2+ cells) and of oligodendrocyte progenitors (OP, NG2+ cells). Progesterone decreased the density of activated astrocytes (GFAP+ cells) and reactive microglia (Iba1+ cells) coexpressing the mannose receptor type 1 CD206 marker. Progesterone also reduced the expression of aquaporin 4 (AQP4), the water channel involved in both edema formation and resorption. The beneficial effects of progesterone were not observed in PRNesCre mice. Our findings show that progesterone treatment exerts beneficial effects on neurons, oligodendroglial cells and neuroinflammatory responses via PR. These findings demonstrate that progesterone is a pleiotropic cerebroprotective agent and that neural PR represent a therapeutic target for stroke cerebroprotection.
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Affiliation(s)
- Xiaoyan Zhu
- U1195 Inserm and University Paris-Sud and University Paris-Saclay, 80 rue du Général Leclerc, 94276 Kremlin-Bicêtre, France.
| | - Magalie Fréchou
- U1195 Inserm and University Paris-Sud and University Paris-Saclay, 80 rue du Général Leclerc, 94276 Kremlin-Bicêtre, France.
| | - Michael Schumacher
- U1195 Inserm and University Paris-Sud and University Paris-Saclay, 80 rue du Général Leclerc, 94276 Kremlin-Bicêtre, France.
| | - Rachida Guennoun
- U1195 Inserm and University Paris-Sud and University Paris-Saclay, 80 rue du Général Leclerc, 94276 Kremlin-Bicêtre, France.
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18
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Chen LH, Zhang HT, Xu RX, Li WD, Zhao H, Yang Y, Sun K. Interaction of aquaporin 4 and N-methyl-D-aspartate NMDA receptor 1 in traumatic brain injury of rats. IRANIAN JOURNAL OF BASIC MEDICAL SCIENCES 2018; 21:1148-1154. [PMID: 30483388 PMCID: PMC6251393 DOI: 10.22038/ijbms.2018.29135.7037] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Objective(s): methyl-D-aspartate NMDA receptor (NMDAR) and aquaporin 4 (AQP4) are involved in the molecular cascade of edema after traumatic brain injury (TBI) and are potential targets of studies in pharmacology and medicine. However, their association and interactions are still unknown. Materials and Methods: We established a rat TBI model in this study. The cellular distribution patterns of AQP4 after inhibition of NMDAR were determined by Western blotting and immunoreactive staining. Furthermore, the regulation of NMDA receptor 1 by AQP4 was studied by injection of a viral vector targeting AQP4 by RNAi into the rat brain before TBI. Results: The results suggest that AQP4 protein expression increased significantly (P<0.05) after TBI and was down-regulated by the NMDAR inhibitor MK801. This decrease could be partly reversed using the NMDAR agonist NMDA. This indicated that AQP4 mRNA levels and protein expression are regulated by the NMDA signaling pathway. By injection of AQP4 RNAi viral vector into the brain of TBI rat models, we found that the mRNA and protein levels of NMDAR decreased significantly (P<0.05). This suggested that NMDAR is also regulated by AQP4. Conclusion: These data suggested that the inhibition of AQP4 down-regulates NMDAR expression, which might be one of the mechanisms involved in edema after TBI.
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Affiliation(s)
- Li-Hua Chen
- The Affiliated Bayi Brain Hospital, The PLA Army General Hospital, Beijing 100700, China
| | - Hong-Tian Zhang
- The Affiliated Bayi Brain Hospital, The PLA Army General Hospital, Beijing 100700, China
| | - Ru-Xiang Xu
- The Affiliated Bayi Brain Hospital, The PLA Army General Hospital, Beijing 100700, China
| | - Wen-De Li
- The Affiliated Bayi Brain Hospital, The PLA Army General Hospital, Beijing 100700, China
| | - Hao Zhao
- The Affiliated Bayi Brain Hospital, The PLA Army General Hospital, Beijing 100700, China
| | - Yi Yang
- The Affiliated Bayi Brain Hospital, The PLA Army General Hospital, Beijing 100700, China
| | - Kai Sun
- The Affiliated Bayi Brain Hospital, The PLA Army General Hospital, Beijing 100700, China
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19
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Avola R, Graziano ACE, Pannuzzo G, Albouchi F, Cardile V. New insights on Parkinson's disease from differentiation of SH-SY5Y into dopaminergic neurons: An involvement of aquaporin4 and 9. Mol Cell Neurosci 2018; 88:212-221. [PMID: 29428877 DOI: 10.1016/j.mcn.2018.02.006] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 07/16/2017] [Accepted: 02/07/2018] [Indexed: 12/30/2022] Open
Abstract
The purpose of this research was to explore the behavior of aquaporins (AQPs) in an in vitro model of Parkinson's disease that is a recurrent neurodegenerative disorder caused by the gradual, progressive loss of dopaminergic neurons in the substantia nigra pars compacta. Because of postmortem studies have provided evidences for oxidative damage and alteration of water flow and energy metabolism, we carried out an investigation about AQP4 and 9, demonstrated in the brain to maintain water and energy homeostasis. As an appropriate in vitro cell model, we used SH-SY5Y cultures and induced their differentiation into a mature dopaminergic neuron phenotype with retinoic acid (RA) alone or in association with phorbol-12-myristate-13-acetate (MPA). The association RA plus MPA provided the most complete and mature neuron phenotype, as demonstrated by high levels of β-Tubulin III, MAP-2, and tyrosine hydroxylase. After validation of cell differentiation, the neurotoxin 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) and H2O2 were applied to reproduce a Parkinson's-like stress. The results confirmed RA/MPA differentiated SH-SY5Y as a useful in vitro system for studying neurotoxicity and for using in a MPTP and H2O2-induced Parkinson's disease cell model. Moreover, the data demonstrated that neuronal differentiation, neurotoxicity, neuroinflammation, and oxidative stress are strongly correlated with dynamic changes of AQP4 and 9 transcription and transduction. New in vitro and in vivo experiments are needed to confirm these innovative outcomes.
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Affiliation(s)
- Rosanna Avola
- Department of Biomedical and Biotechnological Science, Section of Physiology, University of Catania, Via Santa Sofia, 97-95123 Catania, Italy.
| | - Adriana Carol Eleonora Graziano
- Department of Biomedical and Biotechnological Science, Section of Physiology, University of Catania, Via Santa Sofia, 97-95123 Catania, Italy.
| | - Giovanna Pannuzzo
- Department of Biomedical and Biotechnological Science, Section of Physiology, University of Catania, Via Santa Sofia, 97-95123 Catania, Italy
| | - Ferdaous Albouchi
- Laboratoire Materiaux Molecules et Applications, Institut Preparatoire au Etude Scientifique et Technique, Faculty of Sciences of Bizerte, University of Carthage, La Marsa, 2070 Tunis, Tunisia
| | - Venera Cardile
- Department of Biomedical and Biotechnological Science, Section of Physiology, University of Catania, Via Santa Sofia, 97-95123 Catania, Italy.
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20
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Watanabe-Matsumoto S, Moriwaki Y, Okuda T, Ohara S, Yamanaka K, Abe Y, Yasui M, Misawa H. Dissociation of blood-brain barrier disruption and disease manifestation in an aquaporin-4-deficient mouse model of amyotrophic lateral sclerosis. Neurosci Res 2017; 133:48-57. [PMID: 29154923 DOI: 10.1016/j.neures.2017.11.001] [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: 09/27/2017] [Revised: 11/06/2017] [Accepted: 11/09/2017] [Indexed: 11/26/2022]
Abstract
Aquaporin-4 (AQP4) is abundantly expressed in the central nervous system and is involved in the water balance in the cellular environment. Previous studies have reported that AQP4 expression is upregulated in rat models of amyotrophic lateral sclerosis (ALS), a fatal disease that affects motor neurons in the brain and spinal cord. In this study, we report that astrocytic AQP4 overexpression is evident during the course of disease in the spinal cord of an ALS mouse model, as well as in tissue from patients with ALS. AQP4 overexpression appears to be specifically associated with ALS because it was not induced by other experimental manipulations that produced acute or chronic gliosis. In order to examine the contribution of AQP4 to ALS disease development, we crossed AQP4 knockout mice with a mouse model of ALS. Significant improvement in blood-brain barrier (BBB) permeability was observed in the AQP4-deficient ALS mouse model. However, the time to disease onset and total lifespan were reduced in the AQP4-deficient ALS mouse model. The contradictory results suggest that changes in AQP4 may be context-dependent and further studies are required to understand the precise contribution of brain water balance in ALS.
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Affiliation(s)
| | - Yasuhiro Moriwaki
- Division of Pharmacology, Faculty of Pharmacy, Keio University, Tokyo, 105-8512, Japan
| | - Takashi Okuda
- Division of Pharmacology, Faculty of Pharmacy, Keio University, Tokyo, 105-8512, Japan
| | - Shinji Ohara
- Department of Neurology, Matsumoto Medical Center, Chushin-Matsumoto Hospital, Matsumoto, 399-0021, Japan
| | - Koji Yamanaka
- Department of Neuroscience and Pathobiology, Research Institute of Environmental Medicine, Nagoya University, Nagoya, 464-8601, Japan
| | - Yoichiro Abe
- Department of Pharmacology, School of Medicine, Keio University, Tokyo, 160-8582, Japan
| | - Masato Yasui
- Department of Pharmacology, School of Medicine, Keio University, Tokyo, 160-8582, Japan
| | - Hidemi Misawa
- Division of Pharmacology, Faculty of Pharmacy, Keio University, Tokyo, 105-8512, Japan.
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Mokhtarudin MJM, Payne SJ. The study of the function of AQP4 in cerebral ischaemia-reperfusion injury using poroelastic theory. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2017; 33:e02784. [PMID: 26991256 DOI: 10.1002/cnm.2784] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Revised: 02/27/2016] [Accepted: 03/06/2016] [Indexed: 06/05/2023]
Abstract
Brain oedema is thought to form and to clear through the use of water-protein channels, aquaporin-4 (AQP4), which are found in the astrocyte endfeet. The model developed here is used to study the function of AQP4 in the formation and elimination of oedema fluid in ischaemia-reperfusion injury. The cerebral space is assumed to be made of four fluid compartments: astrocyte, neuron, ECS and blood microvessels, and a solid matrix for the tissue, and this is modelled using multiple-network poroelastic theory. AQP4 allows the movement of water between astrocyte and the ECS and the microvessels. It is found that the presence of AQP4 may help in reducing vasogenic oedema shown by a decrease in brain tissue extracellular pressure. However, the astrocyte pressure will increase to compensate for this decrease, which may lead to cytotoxic oedema. In addition, the swelling will also depend on the ionic concentrations in the astrocyte and extracellular space, which may change after ischaemic stroke. Understanding the role of AQP4 in oedema may thus help the development of a treatment plan in reducing brain swelling after ischaemia-reperfusion.
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Affiliation(s)
- Mohd Jamil Mohamed Mokhtarudin
- Institute of Biomedical Engineering, Department of Engineering Science, Old Road Campus Research Building, University of Oxford, OX3 7DQ, Headington, Oxford, UK
- Faculty of Mechanical Engineering, University Malaysia Pahang, 26600, Pekan, Pahang, Malaysia
| | - Stephen J Payne
- Institute of Biomedical Engineering, Department of Engineering Science, Old Road Campus Research Building, University of Oxford, OX3 7DQ, Headington, Oxford, UK
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Filippidis AS, Carozza RB, Rekate HL. Aquaporins in Brain Edema and Neuropathological Conditions. Int J Mol Sci 2016; 18:ijms18010055. [PMID: 28036023 PMCID: PMC5297690 DOI: 10.3390/ijms18010055] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Revised: 12/20/2016] [Accepted: 12/20/2016] [Indexed: 01/22/2023] Open
Abstract
The aquaporin (AQP) family of water channels are a group of small, membrane-spanning proteins that are vital for the rapid transport of water across the plasma membrane. These proteins are widely expressed, from tissues such as the renal epithelium and erythrocytes to the various cells of the central nervous system. This review will elucidate the basic structure and distribution of aquaporins and discuss the role of aquaporins in various neuropathologies. AQP1 and AQP4, the two primary aquaporin molecules of the central nervous system, regulate brain water and CSF movement and contribute to cytotoxic and vasogenic edema, where they control the size of the intracellular and extracellular fluid volumes, respectively. AQP4 expression is vital to the cellular migration and angiogenesis at the heart of tumor growth; AQP4 is central to dysfunctions in glutamate metabolism, synaptogenesis, and memory consolidation; and AQP1 and AQP4 adaptations have been seen in obstructive and non-obstructive hydrocephalus and may be therapeutic targets.
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Affiliation(s)
- Aristotelis S Filippidis
- Division of Neurosurgery, Beth Israel Deaconess Medical School, Harvard Medical School, Boston, MA 02115, USA.
- Department of Neurosurgery, Boston Medical Center, Boston University, Boston, MA 02215, USA.
| | | | - Harold L Rekate
- Department of Neurosurgery, The Chiari Institute, Hofstra Northwell School of Medicine, Hempstead, NY 11549, USA.
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Aquaporin-4: A Potential Therapeutic Target for Cerebral Edema. Int J Mol Sci 2016; 17:ijms17101413. [PMID: 27690011 PMCID: PMC5085613 DOI: 10.3390/ijms17101413] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Revised: 08/15/2016] [Accepted: 08/19/2016] [Indexed: 11/17/2022] Open
Abstract
Aquaporin-4 (AQP4) is a family member of water-channel proteins and is dominantly expressed in the foot process of glial cells surrounding capillaries. The predominant expression at the boundaries between cerebral parenchyma and major fluid compartments suggests the function of aquaporin-4 in water transfer into and out of the brain parenchyma. Accumulating evidences have suggested that the dysregulation of aquaporin-4 relates to the brain edema resulting from a variety of neuro-disorders, such as ischemic or hemorrhagic stroke, trauma, etc. During edema formation in the brain, aquaporin-4 has been shown to contribute to the astrocytic swelling, while in the resolution phase, it has been seen to facilitate the reabsorption of extracellular fluid. In addition, aquaporin-4-deficient mice are protected from cytotoxic edema produced by water intoxication and brain ischemia. However, aquaporin-4 deletion exacerbates vasogenic edema in the brain of different pathological disorders. Recently, our published data showed that the upregulation of aquaporin-4 in astrocytes probably contributes to the transition from cytotoxic edema to vasogenic edema. In this review, apart from the traditional knowledge, we also introduce our latest findings about the effects of mesenchymal stem cells (MSCs) and microRNA-29b on aquaporin-4, which could provide powerful intervention tools targeting aquaporin-4.
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Acetazolamide Mitigates Astrocyte Cellular Edema Following Mild Traumatic Brain Injury. Sci Rep 2016; 6:33330. [PMID: 27623738 PMCID: PMC5022024 DOI: 10.1038/srep33330] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Accepted: 08/25/2016] [Indexed: 12/31/2022] Open
Abstract
Non-penetrating or mild traumatic brain injury (mTBI) is commonly experienced in accidents, the battlefield and in full-contact sports. Astrocyte cellular edema is one of the major factors that leads to high morbidity post-mTBI. Various studies have reported an upregulation of aquaporin-4 (AQP4), a water channel protein, following brain injury. AZA is an antiepileptic drug that has been shown to inhibit AQP4 expression and in this study we investigate the drug as a therapeutic to mitigate the extent of mTBI induced cellular edema. We hypothesized that mTBI-mediated astrocyte dysfunction, initiated by increased intracellular volume, could be reduced when treated with AZA. We tested our hypothesis in a three-dimensional in vitro astrocyte model of mTBI. Samples were subject to no stretch (control) or one high-speed stretch (mTBI) injury. AQP4 expression was significantly increased 24 hours after mTBI. mTBI resulted in a significant increase in the cell swelling within 30 min of mTBI, which was significantly reduced in the presence of AZA. Cell death and expression of S100B was significantly reduced when AZA was added shortly before mTBI stretch. Overall, our data point to occurrence of astrocyte swelling immediately following mTBI, and AZA as a promising treatment to mitigate downstream cellular mortality.
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Schmidt MJ, Rummel C, Hauer J, Kolecka M, Ondreka N, McClure V, Roth J. Increased CSF aquaporin-4, and interleukin-6 levels in dogs with idiopathic communicating internal hydrocephalus and a decrease after ventriculo-peritoneal shunting. Fluids Barriers CNS 2016; 13:12. [PMID: 27357498 PMCID: PMC4928270 DOI: 10.1186/s12987-016-0034-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 05/30/2016] [Indexed: 12/03/2022] Open
Abstract
Background Studies in animal models, in which internal hydrocephalus has been induced by obstructing the cerebrospinal fluid pathways, have documented an up-regulation of the concentrations of aquaporin-4 (AQP4) in the brain. In this study, the concentrations of aquaporin-1 (AQP1), AQP1, AQP4 and interleukin-6 (IL-6) were determined in the CSF of dogs with idiopathic communicating hydrocephalus before and after the reduction of intraventricular volume following ventriculo-peritoneal shunt (VP-shunt) treatment. Results The concentrations of AQP4 and IL-6 were increased in the cerebrospinal fluid of dogs with hydrocephalus compared to controls. Both parameters significantly decreased after surgical treatment, accompanied by decrease of ventricular size and the clinical recovery of the dogs. AQP1 was not detectable in CSF. Conclusions Brain AQP4 up-regulation might be a compensatory response in dogs with hydrocephalus. Future determination of AQP4 at the mRNA and protein level in brain tissue is warranted to substantiate this hypothesis.
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Affiliation(s)
- Martin J Schmidt
- Department of Veterinary Clinical Sciences, Small Animal Clinic, Justus-Liebig-University, Frankfurter Strasse 108, 35392, Giessen, Germany.
| | - Christoph Rummel
- Institute for Veterinary Physiology and Biochemistry, Justus-Liebig-University, Frankfurter Strasse 100, 35392, Giessen, Germany
| | - Jessica Hauer
- Department of Veterinary Clinical Sciences, Small Animal Clinic, Justus-Liebig-University, Frankfurter Strasse 108, 35392, Giessen, Germany
| | - Malgorzata Kolecka
- Department of Veterinary Clinical Sciences, Small Animal Clinic, Justus-Liebig-University, Frankfurter Strasse 108, 35392, Giessen, Germany
| | - Nele Ondreka
- Department of Veterinary Clinical Sciences, Small Animal Clinic, Justus-Liebig-University, Frankfurter Strasse 108, 35392, Giessen, Germany
| | - Vanessa McClure
- Department of Companion Animal Clinical Studies, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, Pretoria, 0110, Republic of South Africa
| | - Joachim Roth
- Institute for Veterinary Physiology and Biochemistry, Justus-Liebig-University, Frankfurter Strasse 100, 35392, Giessen, Germany
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Soltani Z, Khaksari M, Shahrokhi N, Mohammadi G, Mofid B, Vaziri A, Amiresmaili S. Effect of estrogen and/or progesterone administration on traumatic brain injury-caused brain edema: the changes of aquaporin-4 and interleukin-6. J Physiol Biochem 2015; 72:33-44. [PMID: 26638215 DOI: 10.1007/s13105-015-0453-5] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Accepted: 11/24/2015] [Indexed: 11/28/2022]
Abstract
The role of aquaporin-4 (AQP4) and interleukin-6 (IL-6) in the development of brain edema post-traumatic brain injury (TBI) has been indicated. The present study was designed to investigate the effect(s) of administration of progesterone (P) and/or estrogen (E) on brain water content, AQP4 expression, and IL-6 levels post-TBI. The ovariectomized rats were divided into 11 groups: sham, one vehicle, two vehicles, E1, E2, P1, P2, E1 + P1, E1 + P2, E2 + P1, and E2 + P2. The brain AQP4 expression, IL-6 levels, and water content were evaluated 24 h after TBI induced by Marmarou's method. The low (E1 and P1) and high (E2 and P2) doses of estrogen and progesterone were administered 30 min post-TBI. The results showed that brain water content and AQP4 expression decreased in the E1, E2, P1, and P2-treated groups. The administration of E1 decreased IL-6 levels. Addition of progesterone decreased the inhibitory effect of E1 and E2 on the accumulation of water in the brain. Administration of E1 + P1 and E1 + P2 decreased the inhibitory effect of E1 on the IL-6 levels and AQP4 protein expression. Our findings suggest that estrogen or progesterone by itself has more effective roles in decrease of brain edema than combination of both. Possible mechanism may be mediated by the alteration of AQP4 and IL-6 expression. However, further studies are required to verify the exact mechanism.
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Affiliation(s)
- Zahra Soltani
- Physiology Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran
| | - Mohammad Khaksari
- Neuroscience Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran.
| | - Nader Shahrokhi
- Physiology Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran
| | - Gholamabbas Mohammadi
- Department of Biochemistry, Medical School of Afzalipour, Kerman University of Medical Sciences, Kerman, Iran
| | - Behshad Mofid
- Department of Neurosurgery, Shahid Bahonar Hospital of Kerman, Kerman, Iran
| | - Ali Vaziri
- Department of Biochemistry, Medical School of Afzalipour, Kerman University of Medical Sciences, Kerman, Iran
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Lopez-Rodriguez AB, Acaz-Fonseca E, Viveros MP, Garcia-Segura LM. Changes in cannabinoid receptors, aquaporin 4 and vimentin expression after traumatic brain injury in adolescent male mice. Association with edema and neurological deficit. PLoS One 2015; 10:e0128782. [PMID: 26039099 PMCID: PMC4454518 DOI: 10.1371/journal.pone.0128782] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Accepted: 04/30/2015] [Indexed: 12/21/2022] Open
Abstract
Traumatic brain injury (TBI) incidence rises during adolescence because during this critical neurodevelopmental period some risky behaviors increase. The purpose of this study was to assess the contribution of cannabinoid receptors (CB1 and CB2), blood brain barrier proteins (AQP4) and astrogliosis markers (vimentin) to neurological deficit and brain edema formation in a TBI weight drop model in adolescent male mice. These molecules were selected since they are known to change shortly after lesion. Here we extended their study in three different timepoints after TBI, including short (24h), early mid-term (72h) and late mid-term (two weeks). Our results showed that TBI induced an increase in brain edema up to 72 h after lesion that was directly associated with neurological deficit. Neurological deficit appeared 24 h after TBI and was completely recovered two weeks after trauma. CB1 receptor expression decreased after TBI and was negatively correlated with edema formation and behavioral impairments. CB2 receptor increased after injury and was associated with high neurological deficit whereas no correlation with edema was found. AQP4 increased after TBI and was positively correlated with edema and neurological impairments as occurred with vimentin expression in the same manner. The results suggest that CB1 and CB2 differ in the mechanisms to resolve TBI and also that some of their neuroprotective effects related to the control of reactive astrogliosis may be due to the regulation of AQP4 expression on the end-feet of astrocytes.
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Affiliation(s)
- Ana Belen Lopez-Rodriguez
- Department of Animal Physiology (II), Biology Faculty, Complutense University of Madrid, Madrid, Spain
- Instituto Cajal, Consejo Superior de Investigaciones Cientificas (CSIC), Madrid, Spain
- * E-mail:
| | - Estefania Acaz-Fonseca
- Department of Animal Physiology (II), Biology Faculty, Complutense University of Madrid, Madrid, Spain
| | - Maria-Paz Viveros
- Instituto Cajal, Consejo Superior de Investigaciones Cientificas (CSIC), Madrid, Spain
| | - Luis M. Garcia-Segura
- Department of Animal Physiology (II), Biology Faculty, Complutense University of Madrid, Madrid, Spain
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Yang C, Liu Z, Li H, Zhai F, Liu J, Bian J. Aquaporin-4 knockdown ameliorates hypoxic-ischemic cerebral edema in newborn piglets. IUBMB Life 2015; 67:182-90. [PMID: 25857369 DOI: 10.1002/iub.1356] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Accepted: 01/20/2015] [Indexed: 11/11/2022]
Abstract
Emerging evidence indicates that the water channel protein aquaporin 4 (AQP4) plays an essential role in water homeostasis and is implicated in the pathogenesis of brain edema. This study aimed to understand the physiological role of AQP4 in hypoxia-ischemia-mediated cytotoxic brain edema. We specifically knocked down AQP4 expression by intracerebral injection of a plasmid containing AQP4 siRNA into a neonatal piglet model. The success of the hypoxia-ischemia-induced piglet model was confirmed by conventional magnetic resonance imaging and diffusion-weighted imaging. AQP4 knockdown led to reduced brain edema accompanied by a higher apparent diffusion coefficient value, compared to the control group injected with a plasmid containing scrambled siRNA. Real-time polymerase chain reaction and immunohistochemical analysis confirmed that AQP4 siRNA significantly reduced AQP4 mRNA and protein expression. Finally, neurological function analysis revealed that AQP4 knockdown significantly improved neurobehavioral manifestation of the piglets after exposure to hypoxia-ischemia. Taken together, these results indicate that AQP4 plays an important role in mediating brain edema in hypoxic-ischemic encephalopathy. Therefore, AQP4 could be a therapeutic target to ameliorate early-stage brain edema.
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Affiliation(s)
- Chao Yang
- Department of Radiology, The Second Affiliated Hospital of Dalian Medical University, Dalian, China
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Nga VDW, Lim J, Choy DKS, Nyein MA, Lu J, Chou N, Yeo TT, Teoh SH. Effects of polycaprolactone-based scaffolds on the blood-brain barrier and cerebral inflammation. Tissue Eng Part A 2015; 21:647-53. [PMID: 25335965 DOI: 10.1089/ten.tea.2013.0779] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Severe pathoanatomical and mechanical injuries compromise patient recovery and survival following penetrating brain injury (PBI). The realization that the blood-brain barrier (BBB) plays a major role in dictating post-PBI events has led to rising interests in possible therapeutic interventions through the BBB. Recently, the choroid plexus has also been suggested as a potential therapeutic target. The use of biocompatible scaffolds for the delivery of therapeutic agents, but little is known about their interaction with cerebral tissue, which has important clinical implications. Therefore, the authors have sought to investigate the effect of polycaprolactone (PCL) and PCL/tricalcium phosphate (PCL/TCP) scaffolds on the maintenance of BBB phenotype posttraumatic brain injury. Cranial defects of 3 mm depth were created in Sprague Dawley rats, and PCL and PCL/TCP scaffolds were subsequently implanted in predetermined locations for a period of 1 week and 1 month. Higher endothelial barrier antigen (EBA) expressions from PCL-based scaffold groups (p>0.05) were found, suggesting slight advantages over the sham group (no scaffold implantation). PCL/TCP scaffold group also expressed EBA to a higher degree (p>0.05) than PCL scaffolds. Importantly, higher capillary count and area as early as 1 week postimplantation suggested lowered ischemia from the PCL/TCP scaffold group as compared with PCL and sham. Evaluation of interlukin-1β expression suggested that the PCL and PCL/TCP scaffolds did not cause prolonged inflammation. BBB transport selectivity was evaluated by the expression of aquaporin-4 (AQP-4). Attenuated expression of AQP-4 in the PCL/TCP group (p<0.05) suggested that PCL/TCP scaffolds altered BBB selectivity to a lower degree as compared with sham and PCL groups, pointing to potential clinical implications in reducing cerebral edema. Taken together, the responses of PCL-based scaffolds with brain tissue suggested safety, and encourages further preclinical evaluation in PBI management with these scaffolds.
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Li Y, Schmidt-Edelkraut U, Poetz F, Oliva I, Mandl C, Hölzl-Wenig G, Schönig K, Bartsch D, Ciccolini F. γ-Aminobutyric A receptor (GABA(A)R) regulates aquaporin 4 expression in the subependymal zone: relevance to neural precursors and water exchange. J Biol Chem 2014; 290:4343-55. [PMID: 25540202 DOI: 10.1074/jbc.m114.618686] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Activation of γ-aminobutyric A receptors (GABA(A)Rs) in the subependymal zone (SEZ) induces hyperpolarization and osmotic swelling in precursors, thereby promoting surface expression of the epidermal growth factor receptor (EGFR) and cell cycle entry. However, the mechanisms underlying the GABAergic modulation of cell swelling are unclear. Here, we show that GABA(A)Rs colocalize with the water channel aquaporin (AQP) 4 in prominin-1 immunopositive (P(+)) precursors in the postnatal SEZ, which include neural stem cells. GABA(A)R signaling promotes AQP4 expression by decreasing serine phosphorylation associated with the water channel. The modulation of AQP4 expression by GABA(A)R signaling is key to its effect on cell swelling and EGFR expression. In addition, GABA(A)R function also affects the ability of neural precursors to swell in response to an osmotic challenge in vitro and in vivo. Thus, the regulation of AQP4 by GABA(A)Rs is involved in controlling activation of neural stem cells and water exchange dynamics in the SEZ.
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Affiliation(s)
- Yuting Li
- From the Department of Neurobiology, Interdisciplinary Center for Neurosciences, University of Heidelberg, Im Neuenheimer Feld 364, 69120 Heidelberg and
| | - Udo Schmidt-Edelkraut
- From the Department of Neurobiology, Interdisciplinary Center for Neurosciences, University of Heidelberg, Im Neuenheimer Feld 364, 69120 Heidelberg and
| | - Fabian Poetz
- From the Department of Neurobiology, Interdisciplinary Center for Neurosciences, University of Heidelberg, Im Neuenheimer Feld 364, 69120 Heidelberg and
| | - Ilaria Oliva
- From the Department of Neurobiology, Interdisciplinary Center for Neurosciences, University of Heidelberg, Im Neuenheimer Feld 364, 69120 Heidelberg and
| | - Claudia Mandl
- From the Department of Neurobiology, Interdisciplinary Center for Neurosciences, University of Heidelberg, Im Neuenheimer Feld 364, 69120 Heidelberg and
| | - Gabriele Hölzl-Wenig
- From the Department of Neurobiology, Interdisciplinary Center for Neurosciences, University of Heidelberg, Im Neuenheimer Feld 364, 69120 Heidelberg and
| | - Kai Schönig
- the Department of Molecular Biology, Central Institute of Mental Health, Medical Faculty Mannheim/Heidelberg University, J5 Mannheim, Germany
| | - Dusan Bartsch
- the Department of Molecular Biology, Central Institute of Mental Health, Medical Faculty Mannheim/Heidelberg University, J5 Mannheim, Germany
| | - Francesca Ciccolini
- From the Department of Neurobiology, Interdisciplinary Center for Neurosciences, University of Heidelberg, Im Neuenheimer Feld 364, 69120 Heidelberg and
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Ikeshima-Kataoka H, Abe Y, Yasui M. Aquaporin 4-dependent expression of glial fibrillary acidic protein and tenascin-C in activated astrocytes in stab wound mouse brain and in primary culture. J Neurosci Res 2014; 93:121-9. [PMID: 25174305 DOI: 10.1002/jnr.23467] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Revised: 05/23/2014] [Accepted: 07/11/2014] [Indexed: 01/14/2023]
Abstract
We previously reported that aquaporin 4 (AQP4) has a neuroimmunological function via astrocytes and microglial cells involving osteopontin. AQP4 is a water channel localized in the endofoot of astrocytes in the brain, and its expression is upregulated after a stab wound to the mouse brain or the injection of methylmercury in common marmosets. In this study, the correlation between the expression of AQP4 and the expression of glial fibrillary acidic protein (GFAP) or tenascin-C (TN-C) in reactive astrocytes was examined in primary cultures and brain tissues of AQP4-deficient mice (AQP4/KO). In the absence of a stab wound to the brain or of any stimulation of the cells, the expressions of both GFAP and TN-C were lower in astrocytes from AQP4/KO mice than in those from wild-type (WT) mice. High levels of GFAP and TN-C expression were observed in activated astrocytes after a stab wound to the brain in WT mice; however, the expressions of GFAP and TN-C were insignificant in AQP4/KO mice. Furthermore, lipopolysaccharide (LPS) stimulation activated primary culture of astrocytes and upregulated GFAP and TN-C expression in cells from WT mice, whereas the expressions of GFAP and TN-C were slightly upregulated in cells from AQP4/KO mice. Moreover, the stimulation of primary culture of astrocytes with LPS also upregulated inflammatory cytokines in cells from WT mice, whereas modest increases were observed in cells from AQP4/KO mice. These results suggest that AQP4 expression accelerates GFAP and TN-C expression in activated astrocytes induced by a stab wound in the mouse brain and LPS-stimulated primary culture of astrocytes.
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Affiliation(s)
- Hiroko Ikeshima-Kataoka
- Department of Pharmacology and Neuroscience, Keio University School of Medicine, Tokyo, Japan; Faculty of Science and Engineering, Waseda University, Tokyo, Japan
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Ceccariglia S, D’altocolle A, Del Fa’ A, Silvestrini A, Barba M, Pizzolante F, Repele A, Michetti F, Gangitano C. Increased expression of Aquaporin 4 in the rat hippocampus and cortex during trimethyltin-induced neurodegeneration. Neuroscience 2014; 274:273-88. [DOI: 10.1016/j.neuroscience.2014.05.047] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Revised: 05/21/2014] [Accepted: 05/21/2014] [Indexed: 12/12/2022]
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Ding Z, Zhang J, Xu J, Sheng G, Huang G. Propofol administration modulates AQP-4 expression and brain edema after traumatic brain injury. Cell Biochem Biophys 2014; 67:615-22. [PMID: 23494261 DOI: 10.1007/s12013-013-9549-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The increased intracranial pressure caused by brain edema following traumatic brain injury (TBI) always leads to poor patient prognosis. Aquaporin-4 (AQP-4) plays an important role in edema formation and resolution, which may provide a novel therapeutic target for edema treatment. In this present study, we found that propofol treatment, within a short time, after TBI significantly reduced brain edema in a controlled cortical injury rat model and suppressed in vivo expression of AQP-4. The ameliorating effect of propofol was associated with attenuated expression of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α). In addition, the regulatory effect of propofol on AQP-4 expression was investigated in cultured astrocytes. Results showed that propofol could block the stimulatory effect of IL-1β and TNF-α on AQP-4 expression in cultured astrocytes. We also found that both NFκB and p38/MAPK pathways were involved in IL-1β and TNF-α-induced AQP-4 expression and that propofol functions as a dual inhibitor of NFκB and p38/MAPK pathways. In conclusion, treatment with propofol, within a short time, after TBI attenuates cerebral edema and reduces the expression of AQP-4. Propofol modulates acute AQP-4 expression by attenuating IL-1β and TNF-α expression and inhibiting IL-1β and TNF-α induced AQP-4 expression.
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Affiliation(s)
- Zhongyang Ding
- Emergency Center, The Affiliated Wuxi People's Hospital, Nanjing Medical University, Wuxi, 214023, China,
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35
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Mobasheri A, Barrett-Jolley R. Aquaporin water channels in the mammary gland: from physiology to pathophysiology and neoplasia. J Mammary Gland Biol Neoplasia 2014; 19:91-102. [PMID: 24338153 PMCID: PMC3947960 DOI: 10.1007/s10911-013-9312-6] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2013] [Accepted: 11/13/2013] [Indexed: 12/21/2022] Open
Abstract
Aquaporins are membrane proteins that play fundamental roles in water and small solute transport across epithelial and endothelial barriers. Recent studies suggest that several aquaporin proteins are present in the mammary gland. Immunohistochemical techniques have confirmed the presence of aquaporin 1 (AQP1) and AQP3 water channels in rat, mouse, bovine and human mammary glands. Studies suggest that in addition to AQP1 and AQP3 AQP4, AQP5 and AQP7 proteins are expressed in different locations in the mammary gland. Aquaporins play key roles in tumor biology and are involved in cell growth, migration and formation of ascites via increased water permeability of micro-vessels. Emerging evidence suggests that expression of these proteins is altered in mammary tumors and in breast cancer cell lines although it is not yet clear whether this is a cause or a consequence of neoplastic development. This review analyzes the expression and potential functional roles of aquaporin water channels in the mammary gland. The physiological mechanisms involved in the transport of water and small solutes across mammary endothelial and epithelial barriers are discussed in the context of milk production and lactation. This paper also reviews papers from the recent cancer literature that implicate aquaporins in mammary neoplasia.
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Affiliation(s)
- Ali Mobasheri
- School of Pharmacy, University of Bradford, Richmond Road, Bradford, BD7 1DP, UK,
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Adenosine and glutamate in neuroglial interaction: implications for circadian disorders and alcoholism. ADVANCES IN NEUROBIOLOGY 2014; 11:103-19. [PMID: 25236726 DOI: 10.1007/978-3-319-08894-5_6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Recent studies have demonstrated that the function of glia is not restricted to the support of neuronal function. In fact, astrocytes are essential for neuronal activity in the brain and play an important role in the regulation of complex behavior. Astrocytes actively participate in synapse formation and brain information processing by releasing and uptaking glutamate, D-serine, adenosine 5'-triphosphate (ATP), and adenosine. In the central nervous system, adenosine-mediated neuronal activity modulates the actions of other neurotransmitter systems. Adenosinergic fine-tuning of the glutamate system in particular has been shown to regulate circadian rhythmicity and sleep, as well as alcohol-related behavior and drinking. Adenosine gates both photic (light-induced) glutamatergic and nonphotic (alerting) input to the circadian clock located in the suprachiasmatic nucleus of the hypothalamus. Astrocytic, SNARE-mediated ATP release provides the extracellular adenosine that drives homeostatic sleep. Acute ethanol increases extracellular adenosine, which mediates the ataxic and hypnotic/sedative effects of alcohol, while chronic ethanol leads to downregulated adenosine signaling that underlies insomnia, a major predictor of relapse. Studies using mice lacking the equilibrative nucleoside transporter 1 have illuminated how adenosine functions through neuroglial interactions involving glutamate uptake transporter GLT-1 [referred to as excitatory amino acid transporter 2 (EAAT2) in human] and possibly water channel aquaporin 4 to regulate ethanol sensitivity, reward-related motivational processes, and alcohol intake.
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Foxo3a transcriptionally upregulates AQP4 and induces cerebral edema following traumatic brain injury. J Neurosci 2013; 33:17398-403. [PMID: 24174672 DOI: 10.1523/jneurosci.2756-13.2013] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Increased cranial pressure due to development of edema contributes significantly to the pathology of traumatic brain injury (TBI). Induction of an astrocytic water channel protein, Aquaporin 4 (AQP4), is known to predominantly contribute to cytotoxic edema following TBI. However, the mechanism for the increase in AQP4 following 24 h of TBI is poorly understood. Here we show that transcriptional activation of a ubiquitously expressed mammalian forkhead transcription factor, Foxo3a, induces cerebral edema by increasing the AQP4 level in the controlled cortical impact model of TBI in mice. TBI stimulates nuclear translocation of Foxo3a in astrocytes and subsequently augments its binding to AQP4 promoter in pericontusional cortex. Nuclear accumulation of Foxo3a is augmented by a decrease in phosphorylation at its Ser256 residue due to inactivation of Akt after TBI. Depletion of Foxo3a in mice rescues cytotoxic edema by preventing induction of AQP4 as well as attenuates memory impairment after TBI in mice.
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Thumburu KK, Dhiman RK, Vasishta RK, Chakraborti A, Butterworth RF, Beauchesne E, Desjardins P, Goyal S, Sharma N, Duseja A, Chawla Y. Expression of astrocytic genes coding for proteins implicated in neural excitation and brain edema is altered after acute liver failure. J Neurochem 2013; 128:617-27. [PMID: 24164438 DOI: 10.1111/jnc.12511] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Revised: 09/14/2013] [Accepted: 10/11/2013] [Indexed: 01/01/2023]
Abstract
In vitro and in vivo studies have suggested that reduced astrocytic uptake of neuronally released glutamate, alterations in expression of glial fibrillary acidic protein (GFAP) and aquaporin-4 (AQP-4) contribute to brain edema in acute liver failure (ALF). However, there is no evidence to date to suggest that these alterations occur in patients with ALF. We analyzed the mRNA expression of excitatory amino acid transporters (EAAT-1, EAAT-2), GFAP, and AQP-4 in the cerebral cortex obtained at autopsy from eight patients with ALF and from seven patients with no evidence of hepatic or neurological disorders by real-time PCR, and protein expression was assessed using immunoblotting and immunohistochemistry. We demonstrated a significant decrease in GFAP mRNA and protein levels in ALF patients compared to controls. While the loss of EAAT-2 protein in ALF samples was post-translational in nature, EAAT-1 protein remained within normal limits. Immunohistochemistry confirmed that, in all cases, the losses of EAAT-2 and GFAP were uniquely astrocytic in their localization. AQP-4 mRNA expression was significantly increased and its immunohistochemistry demonstrated increased AQP-4 immunoreactivity in the glial end-feet process surrounding the microvessels. These findings provide evidence of selective alterations in the expression of genes coding for key astrocytic proteins implicated in central nervous system (CNS) excitability and brain edema in human ALF. We investigated the gene expression of astrocytic proteins involved in astrocyte swelling causing brain edema in autopsied brain tissues of patients with acute liver failure. This study demonstrated loss of GFAP expression and up-regulation of AQP-4 protein expression leading to cerebral edema, and loss of EAAT-2 expression implicated in excitatory neurotransmission. These findings may provide new drug targets against CNS complications of acute liver failure.
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Affiliation(s)
- Kiran K Thumburu
- Department of Hepatology, Postgraduate Institute of Medical Education & Research, Chandigarh, India
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Chiu CD, Chen CCV, Shen CC, Chin LT, Ma HI, Chuang HY, Cho DY, Chu CH, Chang C. Hyperglycemia exacerbates intracerebral hemorrhage via the downregulation of aquaporin-4: temporal assessment with magnetic resonance imaging. Stroke 2013; 44:1682-9. [PMID: 23592763 DOI: 10.1161/strokeaha.113.675983] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND AND PURPOSE Intracerebral hemorrhage (ICH) is associated with high mortality and neurological deficits, and concurrent hyperglycemia usually worsens clinical outcomes. Aquaporin-4 (AQP-4) is important in cerebral water movement. Our aim was to investigate the role of AQP-4 in hyperglycemic ICH. METHODS Hyperglycemia was induced by intraperitoneal injection of streptozotocin (STZ; 60 mg/kg) in adult Sprague-Dawley male rats. ICH was induced by stereotaxic infusion of collagenase/heparin into the right striatum. One set of rats was repeatedly monitored by MRI at 1, 4, and 7 days after ICH induction so as to acquire information on the formation of hematoma and edema. Another set of rats was killed and brains were examined for differences in the degree of hemorrhage and edema, water content, blood-brain barrier destruction, and AQP-4 expression. RESULTS Hyperglycemia ICH rats exhibited increased brain water content, more severe blood-brain barrier destruction, and greater vasogenic edema as seen on diffusion-weighted MRI. Significant downregulation of AQP-4 was observed in STZ-treated rats after ICH as compared with non-STZ-treated rats. Apoptosis was greater on day 1 after ICH in STZ-treated rats. CONCLUSIONS The expression of AQP-4 in the brain is downregulated in hyperglycemic rats as compared with normoglycemic rats after ICH. This change is accompanied by increased vasogenic brain edema and more severe blood-brain barrier destruction.
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Affiliation(s)
- Cheng-Di Chiu
- Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan
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40
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Lee MR, Ruby CL, Hinton DJ, Choi S, Adams CA, Young Kang N, Choi DS. Striatal adenosine signaling regulates EAAT2 and astrocytic AQP4 expression and alcohol drinking in mice. Neuropsychopharmacology 2013; 38:437-45. [PMID: 23032072 PMCID: PMC3547194 DOI: 10.1038/npp.2012.198] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Adenosine signaling is implicated in several neuropsychiatric disorders, including alcoholism. Among its diverse functions in the brain, adenosine regulates glutamate release and has an essential role in ethanol sensitivity and preference. However, the molecular mechanisms underlying adenosine-mediated glutamate signaling in neuroglial interaction remain elusive. We have previously shown that mice lacking the ethanol-sensitive adenosine transporter, type 1 equilibrative nucleoside transporter (ENT1), drink more ethanol compared with wild-type mice and have elevated striatal glutamate levels. In addition, ENT1 inhibition or knockdown reduces glutamate transporter expression in cultured astrocytes. Here, we examined how adenosine signaling in astrocytes contributes to ethanol drinking. Inhibition or deletion of ENT1 reduced the expression of type 2 excitatory amino-acid transporter (EAAT2) and the astrocyte-specific water channel, aquaporin 4 (AQP4). EAAT2 and AQP4 colocalization was also reduced in the striatum of ENT1 null mice. Ceftriaxone, an antibiotic compound known to increase EAAT2 expression and function, elevated not only EAAT2 but also AQP4 expression in the striatum. Furthermore, ceftriaxone reduced ethanol drinking, suggesting that ENT1-mediated downregulation of EAAT2 and AQP4 expression contributes to excessive ethanol consumption in our mouse model. Overall, our findings indicate that adenosine signaling regulates EAAT2 and astrocytic AQP4 expressions, which control ethanol drinking in mice.
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Affiliation(s)
- Moonnoh R Lee
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic College of Medicine, Rochester, MN, USA,Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - Christina L Ruby
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - David J Hinton
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - Sun Choi
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - Chelsea A Adams
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - Na Young Kang
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic College of Medicine, Rochester, MN, USA
| | - Doo-Sup Choi
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic College of Medicine, Rochester, MN, USA,Department of Psychiatry and Psychology, Mayo Clinic College of Medicine, Rochester, MN, USA,Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN 55905, USA. Tel: +1 507 284-5602, Fax: +1 507 266-0824, E-mail:
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Kleindienst A, Dunbar JG, Glisson R, Marmarou A. The role of vasopressin V1A receptors in cytotoxic brain edema formation following brain injury. Acta Neurochir (Wien) 2013. [PMID: 23188468 DOI: 10.1007/s00701-012-1558-z] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND The hormone and neuropeptide arginine-vasopressin is designated to the maintenance of osmotic homoeostasis and blood pressure regulation. While experimental data show vasopressin V(1A) receptors to regulate aquaporin (AQP)4 water channel dependent brain water movement, the specific role in vasogenic and cytotoxic edema formation remains unclear. The present study was designed to quantify the V(1A) receptor mediated regional brain edema formation in two clinically relevant experimental models, brain injury combined with secondary insult and focal ischemia. METHODS Male Sprague-Dawley rats were randomly assigned to a continuous infusion of vehicle (1 % DMSO) or the selective non-peptide V(1A) antagonist SR49059 (83nM = 1 mg/kg) starting before controlled cortical impact (CCI) injury plus hypoxia and hypotension (HH, 30 min), or middle cerebral artery (MCA) occlusion (2 h + 2 h reperfusion). RESULTS A global analysis of brain water content by the wet/dry weight method allowed optimizing the SR49059 dosage, and demonstrated the down-regulation of brain AQP4 expression by immunoblotting. Microgravimetrical quantification in 64 one mm(3) samples per animal (n = 6 per group) from bregma +2.7 to -6.3 mm analysis demonstrated brain edema to be reduced at 4 h by SR49059 treatment in the injured and contralateral cortex following CCI + HH (p = 0.007, p < 0.001) and in the infarct area following MCA occlusion (p = 0.013, p = 0.002, p = 0.004). CONCLUSIONS Our findings demonstrate that an early cytotoxic brain edema component following brain injury plus secondary insult or focal ischemia results from a vasopressin V(1A) receptor mediated response, and occurs most likely through AQP4 up-regulation. The V(1A) antagonist SR49059 offers a new avenue in brain edema treatment and prompts further study into the role of vasopressin following brain injury.
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Affiliation(s)
- Andrea Kleindienst
- Department of Neurosurgery, Virginia Commonwealth University, 1101 E. Marshall St., 23298, Richmond, VA, USA.
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Wang T, Chou DYT, Ding JY, Fredrickson V, Peng C, Schafer S, Guthikonda M, Kreipke C, Rafols JA, Ding Y. Reduction of brain edema and expression of aquaporins with acute ethanol treatment after traumatic brain injury. J Neurosurg 2012. [PMID: 23198799 DOI: 10.3171/2012.8.jns12736] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
OBJECT Previous studies have demonstrated that traumatic brain injury (TBI) causes brain edema by allowing excessive water passage through aquaporin (AQP) proteins. To establish the potential neuroprotective properties of ethanol as a post-TBI therapy, in the present study the authors determined the effect of ethanol on brain edema, AQP expression, and functional outcomes in a post-TBI setting. METHODS Adult male Sprague-Dawley rats weighing between 425 and 475 g received a closed head TBI in which Maramarou's impact-acceleration method was used. Animals were given a subsequent intraperitoneal injection of 0.5 g/kg or 1.5 g/kg ethanol at 60 minutes post-TBI and were killed 24 hours after TBI. Brains were subsequently examined for edema along with AQP mRNA and protein expression. Additional animals treated with either 0.5 g/kg or 1.5 g/kg ethanol at 60 minutes post-TBI were designated for cognitive and motor testing for 3 weeks. RESULTS Ethanol administration post-TBI led to significantly (p < 0.05) lower levels of brain edema as measured by brain water content. This downregulation in brain edema was associated with significantly (p < 0.05) reduced levels of AQP mRNA and protein expression as compared with TBI without treatment. These findings concur with cognitive studies in which ethanol-treated animals exhibited significantly (p < 0.05) faster radial maze completion times. Motor behavioral testing additionally demonstrated significant (p < 0.05) beneficial effects of ethanol, with treated animals displaying improved motor coordination when compared with untreated animals. CONCLUSIONS The present findings suggest that acute ethanol administration after a TBI decreases AQP expression, which may lead to reduced cerebral edema. Ethanol-treated animals additionally showed improved cognitive and motor outcomes compared with untreated animals.
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Affiliation(s)
- Tony Wang
- Department of Neurological Surgery, Wayne State University School of Medicine, Detroit, Michigan 48201, USA
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Lo Pizzo M, Schiera G, Di Liegro I, Di Liegro CM, Pál J, Czeiter E, Sulyok E, Dóczi T. Aquaporin-4 distribution in control and stressed astrocytes in culture and in the cerebrospinal fluid of patients with traumatic brain injuries. Neurol Sci 2012; 34:1309-14. [PMID: 23143012 DOI: 10.1007/s10072-012-1233-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2012] [Accepted: 10/25/2012] [Indexed: 11/28/2022]
Abstract
Distribution of aquaporin-4 (AQP4) was studied by western analysis and immunofluorescence in rat astrocytes exposed to either hypothermic (30 °C) or hyperosmolar (0.45 M sucrose) stress, and in the cerebrospinal fluid (CSF) of patients who suffered traumatic brain injury (TBI). CSF was obtained from 5 healthy subjects and from 20 patients suffering from severe TBI. CSF samples were taken at admission and on days 3 and 5-7. Here we report that, in response to both hypothermia and hyperosmolar stress, AQP4 was markedly reduced in cultured astrocytes. We also found that AQP4 significantly increased in patients with severe brain injury in respect to healthy subjects (P < 0.002). AQP4 in CSF remained unchanged in patients with elevated intracranial pressure (ICP), whereas there was a clear tendency to further increase in those patients whose ICP could be controlled within the normal range. We conclude that AQP4 levels in CSF are elevated after TBI and it might serve as a useful biochemical marker to assess brain water metabolism in clinical settings.
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Affiliation(s)
- Marianna Lo Pizzo
- Department of di Experimental Biomedicine and Clinical Neurosciences (BIONEC), University of Palermo, I-90127, Palermo, Italy
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44
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Brain water channel proteins in health and disease. Mol Aspects Med 2012; 33:562-78. [DOI: 10.1016/j.mam.2012.03.008] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Revised: 03/28/2012] [Accepted: 03/31/2012] [Indexed: 02/07/2023]
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45
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Roales-Buján R, Páez P, Guerra M, Rodríguez S, Vío K, Ho-Plagaro A, García-Bonilla M, Rodríguez-Pérez LM, Domínguez-Pinos MD, Rodríguez EM, Pérez-Fígares JM, Jiménez AJ. Astrocytes acquire morphological and functional characteristics of ependymal cells following disruption of ependyma in hydrocephalus. Acta Neuropathol 2012; 124:531-46. [PMID: 22576081 PMCID: PMC3444707 DOI: 10.1007/s00401-012-0992-6] [Citation(s) in RCA: 77] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2012] [Revised: 04/25/2012] [Accepted: 04/27/2012] [Indexed: 01/10/2023]
Abstract
Hydrocephalic hyh mutant mice undergo a programmed loss of the neuroepithelium/ependyma followed by a reaction of periventricular astrocytes, which form a new cell layer covering the denuded ventricular surface. We present a comparative morphological and functional study of the newly formed layer of astrocytes and the multiciliated ependyma of hyh mice. Transmission electron microscopy, immunocytochemistry for junction proteins (N-cadherin, connexin 43) and proteins involved in permeability (aquaporin 4) and endocytosis (caveolin-1, EEA1) were used. Horseradish peroxidase (HRP) and lanthanum nitrate were used to trace the intracellular and paracellular transport routes. The astrocyte layer shares several cytological features with the normal multiciliated ependyma, such as numerous microvilli projected into the ventricle, extensive cell–cell interdigitations and connexin 43-based gap junctions, suggesting that these astrocytes are coupled to play an unknown function as a cell layer. The ependyma and the astrocyte layers also share transport properties: (1) high expression of aquaporin 4, caveolin-1 and the endosome marker EEA1; (2) internalization into endocytic vesicles and early endosomes of HRP injected into the ventricle; (3) and a similar paracellular route of molecules moving between CSF, the subependymal neuropile and the pericapillary space, as shown by lanthanum nitrate and HRP. A parallel analysis performed in human hydrocephalic foetuses indicated that a similar phenomenon would occur in humans. We suggest that in foetal-onset hydrocephalus, the astrocyte assembly at the denuded ventricular walls functions as a CSF–brain barrier involved in water and solute transport, thus contributing to re-establish lost functions at the brain parenchyma–CSF interphase.
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Affiliation(s)
- Ruth Roales-Buján
- Departamento de Biología Celular, Genética y Fisiología, Universidad de Málaga, Campus Universitario de Teatinos, 29071 Málaga, Spain
| | - Patricia Páez
- Departamento de Biología Celular, Genética y Fisiología, Universidad de Málaga, Campus Universitario de Teatinos, 29071 Málaga, Spain
| | - Montserrat Guerra
- Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile
| | - Sara Rodríguez
- Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile
| | - Karin Vío
- Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile
| | - Ailec Ho-Plagaro
- Departamento de Biología Celular, Genética y Fisiología, Universidad de Málaga, Campus Universitario de Teatinos, 29071 Málaga, Spain
| | - María García-Bonilla
- Departamento de Biología Celular, Genética y Fisiología, Universidad de Málaga, Campus Universitario de Teatinos, 29071 Málaga, Spain
| | - Luis-Manuel Rodríguez-Pérez
- Departamento de Biología Celular, Genética y Fisiología, Universidad de Málaga, Campus Universitario de Teatinos, 29071 Málaga, Spain
| | - María-Dolores Domínguez-Pinos
- Departamento de Biología Celular, Genética y Fisiología, Universidad de Málaga, Campus Universitario de Teatinos, 29071 Málaga, Spain
| | - Esteban-Martín Rodríguez
- Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile
| | - José-Manuel Pérez-Fígares
- Departamento de Biología Celular, Genética y Fisiología, Universidad de Málaga, Campus Universitario de Teatinos, 29071 Málaga, Spain
| | - Antonio-Jesús Jiménez
- Departamento de Biología Celular, Genética y Fisiología, Universidad de Málaga, Campus Universitario de Teatinos, 29071 Málaga, Spain
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Bhattacharya P, Pandey AK, Paul S, Patnaik R. Neuroprotective potential of Piroxicam in cerebral ischemia: An in silico evaluation of the hypothesis to explore its therapeutic efficacy by inhibition of aquaporin-4 and acid sensing ion channel1a. Med Hypotheses 2012; 79:352-7. [DOI: 10.1016/j.mehy.2012.05.033] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Revised: 05/02/2012] [Accepted: 05/21/2012] [Indexed: 11/17/2022]
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Tayebati SK, Tomassoni D, Amenta F. Spontaneously hypertensive rat as a model of vascular brain disorder: microanatomy, neurochemistry and behavior. J Neurol Sci 2012; 322:241-9. [PMID: 22726353 DOI: 10.1016/j.jns.2012.05.047] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2012] [Accepted: 05/23/2012] [Indexed: 11/28/2022]
Abstract
Arterial hypertension is the main risk factor for stroke and plays a role in the development of vascular cognitive impairment (VCI) and vascular dementia (VaD). An association between hypertension and reduced cerebral blood flow and VCI is documented and arterial hypertension in midlife is associated with a higher probability of cognitive impairment. These findings suggest that arterial hypertension is a main cause of vascular brain disorder (VBD). Spontaneously hypertensive rat (SHR) is the rat strain most extensively investigated and used for assessing hypertensive brain damage and treatment of it. They are normotensive at birth and at 6months they have a sustained hypertension. Time-dependent rise of arterial blood pressure, the occurrence of brain atrophy, loss of nerve cells and glial reaction are phenomena shared to some extent with hypertensive brain damage in humans. SHR present changes of some neurotransmitter systems that may have functional and behavioral relevance. An impaired cholinergic neurotransmission characterizes SHR, similarly as reported in patients affected by VaD. SHR are also characterized by a dopaminergic hypofunction and noradrenergic hyperactivity similarly as occurs in attention-deficit with hyperactivity disorder (ADHD). Microanatomical, neurochemical and behavioral data on SHR are in favor of the hypothesis that this strain is a suitable model of VBD. Changes in catecholaminergic transmission put forward SHR as a possible model of ADHD as well. Hence SHR could represent a multi-faced model of two important groups of pathologies, VBD and ADHD. As for most models, researchers should always consider that SHR offer some similarities with corresponding human pathologies, but they do not suffer from the same disease. This paper reviews the main microanatomical, neurochemical and behavioral characteristics of SHR with particular reference as an animal model of brain vascular injury.
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Affiliation(s)
- Seyed Khosrow Tayebati
- School of Medicinal Sciences and Health Products, University of Camerino, Camerino, Italy.
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6-Hydroxydopamine leads to T2 hyperintensity, decreased claudin-3 immunoreactivity and altered aquaporin 4 expression in the striatum. Behav Brain Res 2012; 232:148-58. [DOI: 10.1016/j.bbr.2012.04.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2012] [Revised: 03/30/2012] [Accepted: 04/03/2012] [Indexed: 11/23/2022]
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49
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Binder DK, Nagelhus EA, Ottersen OP. Aquaporin-4 and epilepsy. Glia 2012; 60:1203-14. [DOI: 10.1002/glia.22317] [Citation(s) in RCA: 115] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2011] [Accepted: 02/09/2012] [Indexed: 12/17/2022]
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50
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Zhang Y, Zhang YP, Shields LB, Zheng Y, Xu XM, Whittemore SR, Shields CB. Cervical Central Canal Occlusion Induces Noncommunicating Syringomyelia. Neurosurgery 2012; 71:126-37. [DOI: 10.1227/neu.0b013e31824d18ae] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Abstract
BACKGROUND:
Mechanisms underlying the development of noncommunicating syringomyelia are poorly understood.
OBJECTIVE:
To assess the influence of focal arachnoiditis and central canal (CC) occlusion (CCO) on the formation of noncommunicating syringomyelia in the adult rat cervical spinal cord. Expression of pericanalicular aquaporin-4 is also examined.
METHODS:
Sprague-Dawley rats were subjected to circumferential or dorsal arachnoiditis (n = 34). Rats undergoing CCO (n = 69) were divided into 4 groups: group A, kaolin injection at a single site in the dorsal columns near the CC; group B, kaolin injection at multiple sites in the dorsal columns near the CC; group C, saline injection at multiple sites in the dorsal columns near the CC; or group D, controls. Rats were killed at 1, 4, 8, and 12 weeks. The CC area and aquaporin-4 (AQP4) expression were measured at the level of maximal CC enlargement.
RESULTS:
Circumferential and dorsal arachnoiditis induced a mild increase in the CC area at 12 weeks. Single-site CCO induced slight CC enlargement. In contrast, multiple sites of CCO in proximity frequently induced a major expansion of the CC area (up to 50 times). Increased AQP4 expression was observed in pericanalicular astrocytes proportional to the degree of CC expansion.
CONCLUSION:
Multiple sites of CCO created a model of noncommunicating syringomyelia in adult rats. Increased astrocytic AQP4 expression was proportional to the degree of CC expansion. Modulation of aquaporin expression may be a novel target for therapeutic interventions to prevent syringomyelia.
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Affiliation(s)
- Yongjie Zhang
- Kentucky Spinal Cord Injury Research Center and Department of Neurological Surgery, University of Louisville, Louisville, Kentucky
- Department of Human Anatomy Histology and Embryology, Nanjing Medical University, Jiangsu Province, China
| | | | | | - Yiyan Zheng
- Kentucky Spinal Cord Injury Research Center and Department of Neurological Surgery, University of Louisville, Louisville, Kentucky
| | - Xiao-Ming Xu
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute and Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, Indiana
| | - Scott R. Whittemore
- Kentucky Spinal Cord Injury Research Center and Department of Neurological Surgery, University of Louisville, Louisville, Kentucky
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