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Moëlo C, Quillévéré A, Le Roy L, Timsit S. (S)-roscovitine, a CDK inhibitor, decreases cerebral edema and modulates AQP4 and α1-syntrophin interaction on a pre-clinical model of acute ischemic stroke. Glia 2024; 72:322-337. [PMID: 37828900 DOI: 10.1002/glia.24477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 08/22/2023] [Accepted: 09/07/2023] [Indexed: 10/14/2023]
Abstract
Cerebral edema is one of the deadliest complications of ischemic stroke for which there is currently no pharmaceutical treatment. Aquaporin-4 (AQP4), a water-channel polarized at the astrocyte endfoot, is known to be highly implicated in cerebral edema. We previously showed in randomized studies that (S)-roscovitine, a cyclin-dependent kinase inhibitor, reduced cerebral edema 48 h after induction of focal transient ischemia, but its mechanisms of action were unclear. In our recent blind randomized study, we confirmed that (S)-roscovitine was able to reduce cerebral edema by 65% at 24 h post-stroke (t test, p = .006). Immunofluorescence analysis of AQP4 distribution in astrocytes revealed that (S)-roscovitine decreased the non-perivascular pool of AQP4 by 53% and drastically increased AQP4 clusters in astrocyte perivascular end-feet (671%, t test p = .005) compared to vehicle. Non-perivascular and clustered AQP4 compartments were negatively correlated (R = -0.78; p < .0001), suggesting a communicating vessels effect between the two compartments. α1-syntrophin, AQP4 anchoring protein, was colocalized with AQP4 in astrocyte endfeet, and this colocalization was maintained in ischemic area as observed on confocal microscopy. Moreover, (S)-roscovitine increased AQP4/α1-syntrophin interaction (40%, MW p = .0083) as quantified by proximity ligation assay. The quantified interaction was negatively correlated with brain edema in both treated and placebo groups (R = -.57; p = .0074). We showed for the first time, that a kinase inhibitor modulated AQP4/α1-syntrophin interaction, and was implicated in the reduction of cerebral edema. These findings suggest that (S)-roscovitine may hold promise as a potential treatment for cerebral edema in ischemic stroke and as modulator of AQP4 function in other neurological diseases.
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Affiliation(s)
- Cloé Moëlo
- EFS, Université de Bretagne Occidentale, Inserm UMR 1078, GGB, Brest, France
| | - Alicia Quillévéré
- EFS, Université de Bretagne Occidentale, Inserm UMR 1078, GGB, Brest, France
| | - Lucas Le Roy
- EFS, Université de Bretagne Occidentale, Inserm UMR 1078, GGB, Brest, France
| | - Serge Timsit
- EFS, Université de Bretagne Occidentale, Inserm UMR 1078, GGB, Brest, France
- Neurology and Stroke Unit Department, CHRU de Brest, Inserm1078, Université de Bretagne Occidentale, Brest, France
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Lia A, Di Spiezio A, Vitalini L, Tore M, Puja G, Losi G. Ion Channels and Ionotropic Receptors in Astrocytes: Physiological Functions and Alterations in Alzheimer's Disease and Glioblastoma. Life (Basel) 2023; 13:2038. [PMID: 37895420 PMCID: PMC10608464 DOI: 10.3390/life13102038] [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: 09/04/2023] [Revised: 10/03/2023] [Accepted: 10/07/2023] [Indexed: 10/29/2023] Open
Abstract
The human brain is composed of nearly one hundred billion neurons and an equal number of glial cells, including macroglia, i.e., astrocytes and oligodendrocytes, and microglia, the resident immune cells of the brain. In the last few decades, compelling evidence has revealed that glial cells are far more active and complex than previously thought. In particular, astrocytes, the most abundant glial cell population, not only take part in brain development, metabolism, and defense against pathogens and insults, but they also affect sensory, motor, and cognitive functions by constantly modulating synaptic activity. Not surprisingly, astrocytes are actively involved in neurodegenerative diseases (NDs) and other neurological disorders like brain tumors, in which they rapidly become reactive and mediate neuroinflammation. Reactive astrocytes acquire or lose specific functions that differently modulate disease progression and symptoms, including cognitive impairments. Astrocytes express several types of ion channels, including K+, Na+, and Ca2+ channels, transient receptor potential channels (TRP), aquaporins, mechanoreceptors, and anion channels, whose properties and functions are only partially understood, particularly in small processes that contact synapses. In addition, astrocytes express ionotropic receptors for several neurotransmitters. Here, we provide an extensive and up-to-date review of the roles of ion channels and ionotropic receptors in astrocyte physiology and pathology. As examples of two different brain pathologies, we focus on Alzheimer's disease (AD), one of the most diffuse neurodegenerative disorders, and glioblastoma (GBM), the most common brain tumor. Understanding how ion channels and ionotropic receptors in astrocytes participate in NDs and tumors is necessary for developing new therapeutic tools for these increasingly common neurological conditions.
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Affiliation(s)
- Annamaria Lia
- Department Biomedical Science, University of Padova, 35131 Padova, Italy; (A.L.); (A.D.S.)
| | - Alessandro Di Spiezio
- Department Biomedical Science, University of Padova, 35131 Padova, Italy; (A.L.); (A.D.S.)
- Neuroscience Institute (CNR-IN), Padova Section, 35131 Padova, Italy
| | - Lorenzo Vitalini
- Department Life Science, University of Modena and Reggio Emilia, 41125 Modena, Italy; (L.V.); (G.P.)
| | - Manuela Tore
- Institute of Nanoscience (CNR-NANO), Modena Section, 41125 Modena, Italy;
- Department Biomedical Science, Metabolic and Neuroscience, University of Modena and Reggio Emilia, 41125 Modena, Italy
| | - Giulia Puja
- Department Life Science, University of Modena and Reggio Emilia, 41125 Modena, Italy; (L.V.); (G.P.)
| | - Gabriele Losi
- Institute of Nanoscience (CNR-NANO), Modena Section, 41125 Modena, Italy;
- Department Biomedical Science, Metabolic and Neuroscience, University of Modena and Reggio Emilia, 41125 Modena, Italy
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3
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Mader S, Brimberg L, Vo A, Strohl JJ, Crawford JM, Bonnin A, Carrión J, Campbell D, Huerta TS, La Bella A, Berlin R, Dewey SL, Hellman M, Eidelberg D, Dujmovic I, Drulovic J, Bennett JL, Volpe BT, Huerta PT, Diamond B. In utero exposure to maternal anti-aquaporin-4 antibodies alters brain vasculature and neural dynamics in male mouse offspring. Sci Transl Med 2022; 14:eabe9726. [PMID: 35442708 PMCID: PMC9973562 DOI: 10.1126/scitranslmed.abe9726] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The fetal brain is constantly exposed to maternal IgG before the formation of an effective blood-brain barrier (BBB). Here, we studied the consequences of fetal brain exposure to an antibody to the astrocytic protein aquaporin-4 (AQP4-IgG) in mice. AQP4-IgG was cloned from a patient with neuromyelitis optica spectrum disorder (NMOSD), an autoimmune disease that can affect women of childbearing age. We found that embryonic radial glia cells in neocortex express AQP4. These cells are critical for blood vessel and BBB formation through modulation of the WNT signaling pathway. Male fetuses exposed to AQP4-IgG had abnormal cortical vasculature and lower expression of WNT signaling molecules Wnt5a and Wnt7a. Positron emission tomography of adult male mice exposed in utero to AQP4-IgG revealed increased blood flow and BBB leakiness in the entorhinal cortex. Adult male mice exposed in utero to AQP4-IgG had abnormal cortical vessels, fewer dendritic spines in pyramidal and stellate neurons, and more S100β+ astrocytes in the entorhinal cortex. Behaviorally, they showed impairments in the object-place memory task. Neural recordings indicated that their grid cell system, within the medial entorhinal cortex, did not map the local environment appropriately. Collectively, these data implicate in utero binding of AQP4-IgG to radial glia cells as a mechanism for alterations of the developing male brain and adds NMOSD to the conditions in which maternal IgG may cause persistent brain dysfunction in offspring.
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Affiliation(s)
- Simone Mader
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset NY 11030, USA.,Institute of Clinical Neuroimmunology, Biomedical Center of the Ludwig Maximilian University of Munich, Munich 82152, Germany.,Corresponding author
| | - Lior Brimberg
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset NY 11030, USA
| | - An Vo
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset NY 11030, USA
| | - Joshua J. Strohl
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset NY 11030, USA.,Department of Molecular Medicine, Zucker School of Medicine at Hofstra/Northwell, Manhasset, NY 11030, USA
| | - James M. Crawford
- Department of Pathology and Laboratory Medicine, Northwell Health, Manhasset, NY 11030, USA
| | - Alexandre Bonnin
- Department of Physiology and Neurosciences, Zilkha Neurogenetic Institute, University of Southern California, Keck School of Medicine, Los Angeles, CA 90033, USA
| | - Joseph Carrión
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset NY 11030, USA
| | - Delcora Campbell
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset NY 11030, USA
| | - Tomás S. Huerta
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset NY 11030, USA.,Department of Molecular Medicine, Zucker School of Medicine at Hofstra/Northwell, Manhasset, NY 11030, USA
| | - Andrea La Bella
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset NY 11030, USA
| | - Roseann Berlin
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset NY 11030, USA
| | - Stephen L. Dewey
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset NY 11030, USA
| | - Matthew Hellman
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset NY 11030, USA
| | - David Eidelberg
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset NY 11030, USA
| | - Irena Dujmovic
- Clinical Center of Serbia University School of Medicine, Belgrade, 11000, Serbia.,Department of Neurology, University of North Carolina, School of Medicine, Chapel Hill, NC 27517, USA
| | - Jelena Drulovic
- Clinical Center of Serbia University School of Medicine, Belgrade, 11000, Serbia
| | - Jeffrey L. Bennett
- Department of Neurology and Ophthalmology, Programs in Neuroscience and Immunology, University of Colorado Denver, School of Medicine, Denver, CO 80045, USA
| | - Bruce T. Volpe
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset NY 11030, USA
| | - Patricio T. Huerta
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset NY 11030, USA.,Department of Molecular Medicine, Zucker School of Medicine at Hofstra/Northwell, Manhasset, NY 11030, USA
| | - Betty Diamond
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset NY 11030, USA
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Lu H, Zhan Y, Ai L, Chen H, Chen J. AQP4-siRNA alleviates traumatic brain edema by altering post-traumatic AQP4 polarity reversal in TBI rats. J Clin Neurosci 2020; 81:113-119. [PMID: 33222898 DOI: 10.1016/j.jocn.2020.09.015] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 07/13/2020] [Accepted: 09/06/2020] [Indexed: 11/18/2022]
Abstract
The spatial and temporal distribution of aquaporin-4 (AQP4) expression in rat brain following brain trauma and AQP4-siRNA treatment, as well as corresponding pathological changes, were studied to explore the mechanism underlying the effect of AQP4-siRNA treatment on traumatic brain injury (TBI). The rats in the sham operation group had normal structure, with AQP4 located in the perivascular end-foot membranes and astrocytic membranes in a polarized pattern. The accelerated polarity reversal was observed in the TBI group in 1-12 h after TBI. During this period, AQP4 abundance on the astrocytic membrane is gradually increased, while AQP4 abundance on the perivascular end-foot membrane declined rapidly. Twelve hours after TBI, AQP4 expression was depolarized, showing a shift from the perivascular end-foot membrane to the astrocytic membrane. Pathological observation showed that vasogenic edema occurred immediately after TBI, at which time the extracellular space was expanded, leading to severe intracellular edema. AQP4-siRNA reduced the polarity reversal index at the early stage of TBI recovery and reduced edema, demonstrating the potential benefit of reduced AQP4 expression during recovery from TBI.
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Affiliation(s)
- Hong Lu
- Department of Radiology, Chongqing The Seventh Peoplés Hospital, Chongqing, China
| | - Yuefu Zhan
- Department of Radiology, Hainan Women and Children's Medical Center, No. 15, Long Kun Nan road, Haikou, Hainan 572500, China.
| | - Li Ai
- Department of Radiology, Chongqing The Seventh Peoplés Hospital, Chongqing, China
| | - Haixia Chen
- Department of Radiology, Chongqing The Seventh Peoplés Hospital, Chongqing, China
| | - Jianqiang Chen
- Department of Radiology, Xiangya School of Medicine Affiliated Haikou Hospital, Central South University, Haikou, Hainan 570208, China.
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Hackett TA. Adenosine A 1 Receptor mRNA Expression by Neurons and Glia in the Auditory Forebrain. Anat Rec (Hoboken) 2018; 301:1882-1905. [PMID: 30315630 PMCID: PMC6282551 DOI: 10.1002/ar.23907] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 12/05/2017] [Accepted: 01/10/2018] [Indexed: 12/30/2022]
Abstract
In the brain, purines such as ATP and adenosine can function as neurotransmitters and co‐transmitters, or serve as signals in neuron–glial interactions. In thalamocortical (TC) projections to sensory cortex, adenosine functions as a negative regulator of glutamate release via activation of the presynaptic adenosine A1 receptor (A1R). In the auditory forebrain, restriction of A1R‐adenosine signaling in medial geniculate (MG) neurons is sufficient to extend LTP, LTD, and tonotopic map plasticity in adult mice for months beyond the critical period. Interfering with adenosine signaling in primary auditory cortex (A1) does not contribute to these forms of plasticity, suggesting regional differences in the roles of A1R‐mediated adenosine signaling in the forebrain. To advance understanding of the circuitry, in situ hybridization was used to localize neuronal and glial cell types in the auditory forebrain that express A1R transcripts (Adora1), based on co‐expression with cell‐specific markers for neuronal and glial subtypes. In A1, Adora1 transcripts were concentrated in L3/4 and L6 of glutamatergic neurons. Subpopulations of GABAergic neurons, astrocytes, oligodendrocytes, and microglia expressed lower levels of Adora1. In MG, Adora1 was expressed by glutamatergic neurons in all divisions, and subpopulations of all glial classes. The collective findings imply that A1R‐mediated signaling broadly extends to all subdivisions of auditory cortex and MG. Selective expression by neuronal and glial subpopulations suggests that experimental manipulations of A1R‐adenosine signaling could impact several cell types, depending on their location. Strategies to target Adora1 in specific cell types can be developed from the data generated here. Anat Rec, 301:1882–1905, 2018. © 2018 The Authors. The Anatomical Record published by Wiley Periodicals, Inc. on behalf of American Association of Anatomists.
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Affiliation(s)
- Troy A Hackett
- Department of Hearing and Speech Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, USA.,Department of Psychology, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt Brain Institute, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt Kennedy Center for Research on Human Development, Vanderbilt University, Nashville, Tennessee, USA
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6
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Wang H, Wang S, Zhang K, Wang H, Lan L, Ma X, Liu X, Zhang S, Zheng J, Wei X, Yan H. Aquaporin 4 Forms a Macromolecular Complex with Glutamate Transporter 1 and Mu Opioid Receptor in Astrocytes and Participates in Morphine Dependence. J Mol Neurosci 2017; 62:17-27. [PMID: 28341892 DOI: 10.1007/s12031-017-0905-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2017] [Accepted: 02/24/2017] [Indexed: 10/19/2022]
Abstract
The water channel aquaporin 4 (AQP4) is abundantly expressed in astrocytes and provides a mechanism by which water permeability of the plasma membrane can be regulated. Evidence suggests that AQP4 is associated with glutamate transporter-1 (GLT-1) for glutamate clearance and contributes to morphine dependence. Previous studies show that AQP4 deficiency changed the mu opioid receptor expression and opioid receptors' characteristics as well. In this study, we focused on whether AQP4 could form macromolecular complex with GLT-1 and mu opioid receptor (MOR) and participates in morphine dependence. By using immunofluorescence staining, fluorescence resonance energy transfer, and co-immunoprecipitation, we demonstrated that AQP4 forms protein complexes with GLT-1 and MOR in both brain tissue and primary cultured astrocytes. We then showed that the C-terminus of AQP4 containing the amino acid residues 252 to 323 is the site of interaction with GLT-1. Protein kinase C, activated by morphine, played an important role in regulating the expression of these proteins. These findings may help to reveal the mechanism that AQP4, GLT-1, and MOR form protein complex and participate in morphine dependence, and deeply understand the reason that AQP4 deficiency maintains extracellular glutamate homeostasis and attenuates morphine dependence, moreover emphasizes the function of astrocyte in morphine dependence.
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Affiliation(s)
- Hui Wang
- State Key Laboratory of Toxicology and Medical Countermeasures, Department of Biochemical Pharmacology, Beijing Institute of Pharmacology and Toxicology, 27th Taiping Road, Beijing, 100850, China
| | - Shiqi Wang
- State Key Laboratory of Toxicology and Medical Countermeasures, Department of Biochemical Pharmacology, Beijing Institute of Pharmacology and Toxicology, 27th Taiping Road, Beijing, 100850, China
| | - Kang Zhang
- State Key Laboratory of Toxicology and Medical Countermeasures, Department of Biochemical Pharmacology, Beijing Institute of Pharmacology and Toxicology, 27th Taiping Road, Beijing, 100850, China
| | - Hua Wang
- State Key Laboratory of Toxicology and Medical Countermeasures, Department of Biochemical Pharmacology, Beijing Institute of Pharmacology and Toxicology, 27th Taiping Road, Beijing, 100850, China
| | - Liting Lan
- State Key Laboratory of Toxicology and Medical Countermeasures, Department of Biochemical Pharmacology, Beijing Institute of Pharmacology and Toxicology, 27th Taiping Road, Beijing, 100850, China
| | - Xiaoyun Ma
- State Key Laboratory of Toxicology and Medical Countermeasures, Department of Biochemical Pharmacology, Beijing Institute of Pharmacology and Toxicology, 27th Taiping Road, Beijing, 100850, China
| | - Xiaoyan Liu
- State Key Laboratory of Toxicology and Medical Countermeasures, Department of Biochemical Pharmacology, Beijing Institute of Pharmacology and Toxicology, 27th Taiping Road, Beijing, 100850, China
| | - Shuzhuo Zhang
- State Key Laboratory of Toxicology and Medical Countermeasures, Department of Biochemical Pharmacology, Beijing Institute of Pharmacology and Toxicology, 27th Taiping Road, Beijing, 100850, China
| | - Jianquan Zheng
- State Key Laboratory of Toxicology and Medical Countermeasures, Department of Biochemical Pharmacology, Beijing Institute of Pharmacology and Toxicology, 27th Taiping Road, Beijing, 100850, China
| | - Xiaoli Wei
- State Key Laboratory of Toxicology and Medical Countermeasures, Department of Biochemical Pharmacology, Beijing Institute of Pharmacology and Toxicology, 27th Taiping Road, Beijing, 100850, China.
| | - Haitao Yan
- State Key Laboratory of Toxicology and Medical Countermeasures, Department of Biochemical Pharmacology, Beijing Institute of Pharmacology and Toxicology, 27th Taiping Road, Beijing, 100850, China.
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Stokum JA, Mehta RI, Ivanova S, Yu E, Gerzanich V, Simard JM. Heterogeneity of aquaporin-4 localization and expression after focal cerebral ischemia underlies differences in white versus grey matter swelling. Acta Neuropathol Commun 2015; 3:61. [PMID: 26419740 PMCID: PMC4588314 DOI: 10.1186/s40478-015-0239-6] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2015] [Accepted: 09/17/2015] [Indexed: 12/21/2022] Open
Abstract
INTRODUCTION Ischemic stroke, a major cause of mortality, is frequently accompanied by life-threatening cerebral edema. Aquaporin-4 (Aqp4), an astrocytic transmembrane water channel, is an important molecular contributor to cerebral edema formation. Past studies of Aqp4 expression and localization after ischemia examined grey matter exclusively. However, as white matter astrocytes differ developmentally, physiologically, and molecularly from grey matter astrocytes, we hypothesized that functionally important regional heterogeneity exists in Aqp4 expression and subcellular localization following cerebral ischemia. RESULTS Subcellular localization of Aqp4 was compared between cortical and white matter astrocytes in postmortem specimens of patients with focal ischemic stroke versus controls. Subcellular localization and expression of Aqp4 was examined in rats subjected to experimental stroke. Volumetric analysis was performed on the cortex and white matter of rats subjected to experimental stroke. Following cerebral ischemia, cortical astrocytes exhibited reduced perivascular Aqp4 and unchanged Aqp4 protein abundance. In contrast, white matter astrocytes exhibited increased perivascular and plasmalemmal Aqp4 and a 2.2- to 6.2-fold increase in Aqp4 isoform abundance. Ischemic white matter swelled by approximately 40 %, while cortex swelled by approximately 9 %. CONCLUSIONS The findings reported here raise the possibility that cerebral white matter may play a heretofore underappreciated role in the formation of cerebral edema following ischemia.
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Juenemann M, Braun T, Doenges S, Nedelmann M, Mueller C, Bachmann G, Singh P, Blaes F, Gerriets T, Tschernatsch M. Aquaporin-4 autoantibodies increase vasogenic edema formation and infarct size in a rat stroke model. BMC Immunol 2015; 16:30. [PMID: 25986484 PMCID: PMC4437448 DOI: 10.1186/s12865-015-0087-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Accepted: 03/25/2015] [Indexed: 01/01/2023] Open
Abstract
Background Neuromyelitis optica (NMO) is an autoimmune disorder of the central nervous system, which is characterized by autoantibodies directed against the water channel aquaporin-4 (AQP4). As one of the main water regulators in the central nervous system, APQ4 is supposed to be involved in the dynamics of brain edema. Cerebral edema seriously affects clinical outcome after ischemic stroke; we therefore aimed to investigate whether NMO-antibodies may exert the same functional effects as an AQP4-inhibitor in-vivo in acute ischemic stroke. Methods Sixteen male Wistar rats were randomized into two groups twice receiving either purified NMO-IgG or immune globulin from healthy controls, 24 hours and 30 minutes before middle cerebral artery occlusion (MCAO) was performed. T2-weighted MRI was carried out 24 hours after MCAO. Results MRI-examination showed a significant increase of infarct size in relation to the cerebral hemisphere volume with NMO-IgG treated animals (27.1% ± 11.1% vs. 14.3% ± 7.2%; p < 0.05) when corrected for the space-occupying effect of vasogenic edema formation and similar results without edema correction (34.4% ± 16.4% vs. 17.5% ± 9.3%; p < 0.05). Furthermore, T2-RT revealed a significant increase in cortical brain water content of the treatment group (19.5 ms ± 9.7 ms vs. 9.2 ms ± 5.2 ms; p < 0.05). Conclusions These results support the functional impact of NMO-antibodies and also offer an in-vivo-applicable animal model to investigate the properties of AQP4 in ischemic stroke.
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Affiliation(s)
- Martin Juenemann
- Heart & Brain Research Group, Justus-Liebig-University Giessen and Kerckhoff Clinic, Benekestrasse 2-8, 61231, Bad Nauheim, Germany. .,Department of Neurology, Justus-Liebig-University Giessen, Klinikstrasse 33, 35392, Giessen, Germany.
| | - Tobias Braun
- Department of Neurology, Justus-Liebig-University Giessen, Klinikstrasse 33, 35392, Giessen, Germany.
| | - Simone Doenges
- Heart & Brain Research Group, Justus-Liebig-University Giessen and Kerckhoff Clinic, Benekestrasse 2-8, 61231, Bad Nauheim, Germany.
| | - Max Nedelmann
- Heart & Brain Research Group, Justus-Liebig-University Giessen and Kerckhoff Clinic, Benekestrasse 2-8, 61231, Bad Nauheim, Germany. .,Department of Neurology, Justus-Liebig-University Giessen, Klinikstrasse 33, 35392, Giessen, Germany.
| | - Clemens Mueller
- Department of Radiology, Kerckhoff Clinic, Benekestrasse 2-8, 61231, Bad Nauheim, Germany.
| | - Georg Bachmann
- Department of Radiology, Kerckhoff Clinic, Benekestrasse 2-8, 61231, Bad Nauheim, Germany.
| | - Pratibha Singh
- Department of Pharmacology, Max-Planck-Institute for Heart and Lung Research, Ludwigstraße 43, 61231, Bad Nauheim, Germany.
| | - Franz Blaes
- Department of Neurology, Justus-Liebig-University Giessen, Klinikstrasse 33, 35392, Giessen, Germany. .,Department of Neurology, Kreiskrankenhaus Gummersbach, Wilhelm-Breckow-Allee 20, 51643, Gummersbach, Germany.
| | - Tibo Gerriets
- Heart & Brain Research Group, Justus-Liebig-University Giessen and Kerckhoff Clinic, Benekestrasse 2-8, 61231, Bad Nauheim, Germany. .,Department of Neurology, Justus-Liebig-University Giessen, Klinikstrasse 33, 35392, Giessen, Germany. .,Department of Neurology, Buergerhospital Friedberg, Ockstaedter Strasse 3-5, 61169, Friedberg, Germany.
| | - Marlene Tschernatsch
- Department of Neurology, Justus-Liebig-University Giessen, Klinikstrasse 33, 35392, Giessen, Germany.
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Intracellular redistribution of acetyl-CoA, the pivotal point in differential susceptibility of cholinergic neurons and glial cells to neurodegenerative signals. Biochem Soc Trans 2015; 42:1101-6. [PMID: 25110009 DOI: 10.1042/bst20140078] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Intramitochondrial decarboxylation of glucose-derived pyruvate by PDHC (pyruvate dehydrogenase complex) is a principal source of acetyl-CoA, for mitochondrial energy production and cytoplasmic synthetic pathways in all types of brain cells. The inhibition of PDHC, ACO (aconitase) and KDHC (ketoglutarate dehydrogenase complex) activities by neurodegenerative signals such as aluminium, zinc, amyloid β-peptide, excess nitric oxide (NO) or thiamine pyrophosphate deficits resulted in much deeper losses of viability, acetyl-CoA and ATP in differentiated cholinergic neuronal cells than in non-differentiated cholinergic, and cultured microglial or astroglial cell lines. In addition, in cholinergic cells, such conditions caused inhibition of ACh (acetylcholine) synthesis and its quantal release. Furthermore, cholinergic neuronal cells appeared to be resistant to high concentrations of LPS (lipopolysaccharide). In contrast, in microglial cells, low levels of LPS caused severalfold activation of NO, IL-6 (interleukin 6) and TNFα (tumour necrosis factor α) synthesis/release, accompanied by inhibition of PDHC, KDHC and ACO activities, and suppression of acetyl-CoA, but relatively small losses in their ATP contents and viability parameters. Compounds that protected these enzymes against inhibitory effects of neurotoxins alleviated acetyl-CoA and ATP deficits, thereby maintaining neuronal cell viability. These data indicate that preferential susceptibility of cholinergic neurons to neurodegenerative insults may result from competition for acetyl-CoA between mitochondrial energy-producing and cytoplasmic ACh-synthesizing pathways. Such a hypothesis is supported by the existence of highly significant correlations between mitochondrial/cytoplasmic acetyl-CoA levels and cell viability/transmitter functions respectively.
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10
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Brockett AT, LaMarca EA, Gould E. Physical exercise enhances cognitive flexibility as well as astrocytic and synaptic markers in the medial prefrontal cortex. PLoS One 2015; 10:e0124859. [PMID: 25938418 PMCID: PMC4418599 DOI: 10.1371/journal.pone.0124859] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2015] [Accepted: 03/09/2015] [Indexed: 11/23/2022] Open
Abstract
Physical exercise enhances a wide range of cognitive functions in humans. Running-induced cognitive enhancement has also been demonstrated in rodents but with a strong emphasis on tasks that require the hippocampus. Additionally, studies designed to identify mechanisms that underlie cognitive enhancement with physical exercise have focused on running-induced changes in neurons with little attention paid to such changes in astrocytes. To further our understanding of how the brain changes with physical exercise, we investigated whether running alters performance on cognitive tasks that require the prefrontal cortex and whether any such changes are associated with astrocytic, as well as neuronal, plasticity. We found that running enhances performance on cognitive tasks known to rely on the prefrontal cortex. By contrast, we found no such improvement on a cognitive task known to rely on the perirhinal cortex. Moreover, we found that running enhances synaptic, dendritic and astrocytic measures in several brain regions involved in cognition but that changes in the latter measures were more specific to brain regions associated with cognitive improvements. These findings suggest that physical exercise induces widespread plasticity in both neuronal and nonneuronal elements and that both types of changes may be involved in running-induced cognitive enhancement.
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Affiliation(s)
- Adam T. Brockett
- Department of Psychology and Princeton Neuroscience Institute, Princeton University, Princeton, NJ, United States of America
| | - Elizabeth A. LaMarca
- Department of Psychology and Princeton Neuroscience Institute, Princeton University, Princeton, NJ, United States of America
| | - Elizabeth Gould
- Department of Psychology and Princeton Neuroscience Institute, Princeton University, Princeton, NJ, United States of America
- * E-mail:
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Jukkola P, Gu C. Regulation of neurovascular coupling in autoimmunity to water and ion channels. Autoimmun Rev 2015; 14:258-67. [PMID: 25462580 PMCID: PMC4303502 DOI: 10.1016/j.autrev.2014.11.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Accepted: 11/15/2014] [Indexed: 12/27/2022]
Abstract
Much progress has been made in understanding autoimmune channelopathies, but the underlying pathogenic mechanisms are not always clear due to broad expression of some channel proteins. Recent studies show that autoimmune conditions that interfere with neurovascular coupling in the central nervous system (CNS) can lead to neurodegeneration. Cerebral blood flow that meets neuronal activity and metabolic demand is tightly regulated by local neural activity. This process of reciprocal regulation involves coordinated actions of a number of cell types, including neurons, glia, and vascular cells. In particular, astrocytic endfeet cover more than 90% of brain capillaries to assist blood-brain barrier (BBB) function, and wrap around synapses and nodes of Ranvier to communicate with neuronal activity. In this review, we highlight four types of channel proteins that are expressed in astrocytes, regarding their structures, biophysical properties, expression and distribution patterns, and related diseases including autoimmune disorders. Water channel aquaporin 4 (AQP4) and inwardly rectifying potassium (Kir4.1) channels are concentrated in astrocytic endfeet, whereas some voltage-gated Ca(2+) and two-pore domain K(+) channels are expressed throughout the cell body of reactive astrocytes. More channel proteins are found in astrocytes under normal and abnormal conditions. This research field will contribute to a better understanding of pathogenic mechanisms underlying autoimmune disorders.
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Affiliation(s)
- Peter Jukkola
- Biomedical Sciences Graduate Program, The Ohio State University, Columbus, OH 43210, USA
| | - Chen Gu
- Biomedical Sciences Graduate Program, The Ohio State University, Columbus, OH 43210, USA; Department of Neuroscience, The Ohio State University, Columbus, OH 43210, USA.
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Guo W, Feng G, Miao Y, Liu G, Xu C. Rapamycin alleviates brain edema after focal cerebral ischemia reperfusion in rats. Immunopharmacol Immunotoxicol 2014; 36:211-23. [PMID: 24773551 DOI: 10.3109/08923973.2014.913616] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Brain edema is a major consequence of cerebral ischemia reperfusion. However, few effective therapeutic options are available for retarding the brain edema progression after cerebral ischemia. Recently, rapamycin has been shown to produce neuroprotective effects in rats after cerebral ischemia reperfusion. Whether rapamycin could alleviate this brain edema injury is still unclear. In this study, the rat stroke model was induced by a 1-h left transient middle cerebral artery occlusion using an intraluminal filament, followed by 48 h of reperfusion. The effects of rapamycin (250 μg/kg body weight, intraperitoneal; i.p.) on brain edema progression were evaluated. The results showed that rapamycin treatment significantly reduced the infarct volume, the water content of the brain tissue and the Evans blue extravasation through the blood-brain barrier (BBB). Rapamycin treatment could improve histological appearance of the brain tissue, increased the capillary lumen space and maintain the integrity of BBB. Rapamycin also inhibited matrix metalloproteinase 9 (MMP9) and aquaporin 4 (AQP4) expression. These data imply that rapamycin could improve brain edema progression after reperfusion injury through maintaining BBB integrity and inhibiting MMP9 and AQP4 expression. The data of this study provide a new possible approach for improving brain edema after cerebral ischemia reperfusion by administration of rapamycin.
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Affiliation(s)
- Wei Guo
- Department of Neurology, Binzhou Medical College Affiliated Hospital , Binzhou, Shandong Province , China and
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Unique neuromyelitis optica pathology produced in naïve rats by intracerebral administration of NMO-IgG. Acta Neuropathol 2014; 127:539-51. [PMID: 24190619 DOI: 10.1007/s00401-013-1204-8] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Revised: 10/26/2013] [Accepted: 10/27/2013] [Indexed: 10/26/2022]
Abstract
Animal models of neuromyelitis optica (NMO) are needed for elucidation of disease mechanisms and for testing new therapeutics. Prior animal models of NMO involved administration of human anti-aquaporin-4 immunoglobulin G antibody (NMO-IgG) to rats with pre-existing neuroinflammation, or to naïve mice supplemented with human complement. We report here the development of NMO pathology following passive transfer of NMO-IgG to naïve rats. A single intracerebral infusion of NMO-IgG to adult Lewis rats produced robust lesions around the needle track in 100 % of rats; at 5 days there was marked loss of aquaporin-4 (AQP4), glial fibrillary acidic protein (GFAP) and myelin, granulocyte and macrophage infiltration, vasculocentric complement deposition, blood-brain barrier disruption, microglial activation and neuron death. Remarkably, a distinct 'penumbra' was seen around lesions, with loss of AQP4 but not of GFAP or myelin. No lesions or penumbra were seen in rats receiving control IgG. The size of the main lesion with loss of myelin was greatly reduced in rats made complement-deficient by cobra venom factor or administered NMO-IgG lacking complement-dependent cytotoxicity (CDC) effector function. However, the penumbra was seen under these conditions, suggesting a complement-independent pathogenesis mechanism. The penumbra was absent with NMO-IgG lacking both CDC and antibody-dependent cellular cytotoxicity (ADCC) effector functions. Finally, lesion size was significantly reduced after macrophage depletion with clodronate liposomes. These results: (i) establish a robust, passive-transfer model of NMO in rats that does not require pre-existing neuroinflammation or complement administration; (ii) implicate ADCC as responsible for a unique type of pathology also seen in human NMO; and (iii) support a pathogenic role of macrophages in NMO.
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Diclofenac Enhances Proinflammatory Cytokine-Induced Aquaporin-4 Expression in Cultured Astrocyte. Cell Mol Neurobiol 2013; 33:393-400. [DOI: 10.1007/s10571-013-9905-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2012] [Accepted: 01/02/2013] [Indexed: 10/27/2022]
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