151
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Edler MK, Sherwood CC, Meindl RS, Munger E, Hopkins WD, Ely JJ, Erwin JM, Perl DP, Mufson EJ, Hof PR, Raghanti MA. Microglia changes associated to Alzheimer's disease pathology in aged chimpanzees. J Comp Neurol 2018; 526:2921-2936. [PMID: 30069930 PMCID: PMC6283685 DOI: 10.1002/cne.24484] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 05/11/2018] [Accepted: 05/16/2018] [Indexed: 01/01/2023]
Abstract
In Alzheimer's disease (AD), the brain's primary immune cells, microglia, become activated and are found in close apposition to amyloid beta (Aβ) protein plaques and neurofibrillary tangles (NFT). The present study evaluated microglia density and morphology in a large group of aged chimpanzees (n = 20, ages 37-62 years) with varying degrees of AD-like pathology. Using immunohistochemical and stereological techniques, we quantified the density of activated microglia and morphological variants (ramified, intermediate, and amoeboid) in postmortem chimpanzee brain samples from prefrontal cortex, middle temporal gyrus, and hippocampus, areas that show a high degree of AD pathology in humans. Microglia measurements were compared to pathological markers of AD in these cases. Activated microglia were consistently present across brain areas. In the hippocampus, CA3 displayed a higher density than CA1. Aβ42 plaque volume was positively correlated with higher microglial activation and with an intermediate morphology in the hippocampus. Aβ42-positive vessel volume was associated with increased hippocampal microglial activation. Activated microglia density and morphology were not associated with age, sex, pretangle density, NFT density, or tau neuritic cluster density. Aged chimpanzees displayed comparable patterns of activated microglia phenotypes as well as an association of increased microglial activation and morphological changes with Aβ deposition similar to AD patients. In contrast to human AD brains, activated microglia density was not significantly correlated with tau lesions. This evidence suggests that the chimpanzee brain may be relatively preserved during normal aging processes but not entirely protected from neurodegeneration as previously assumed.
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Affiliation(s)
- Melissa K. Edler
- School of Biomedical Sciences, Kent State University, Kent, OH 44242
- Department of Pharmaceutical Sciences, Northeast Ohio Medical University, Rootstown, OH 44272
| | - Chet C. Sherwood
- Department of Anthropology and Center for the Advanced Study of Human Paleobiology, The George Washington University, Washington, DC 20052
| | | | - Emily Munger
- School of Biomedical Sciences, Kent State University, Kent, OH 44242
| | - William D. Hopkins
- Division of Developmental and Cognitive Neuroscience, Yerkes National Primate Research Center, Atlanta, GA 30322
- Neuroscience Institute, Georgia State University, Atlanta, GA 30302
| | | | - Joseph M. Erwin
- Department of Anthropology and Center for the Advanced Study of Human Paleobiology, The George Washington University, Washington, DC 20052
| | - Daniel P. Perl
- Department of Pathology, Uniformed Services University of the Health Sciences, Bethesda, MD 20814
| | - Elliott J. Mufson
- Departments of Neurobiology and Neurology, Barrow Neurological Institute, Phoenix, AZ 85013
| | - Patrick R. Hof
- Fishberg Department of Neuroscience, Ronald M. Loeb Center for Alzheimer’s Disease, and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029
- New York Consortium for Evolutionary Primatology, New York, NY 10468
| | - Mary Ann Raghanti
- School of Biomedical Sciences, Kent State University, Kent, OH 44242
- Department of Anthropology, Kent State University, Kent, OH 44242
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152
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3DMorph Automatic Analysis of Microglial Morphology in Three Dimensions from Ex Vivo and In Vivo Imaging. eNeuro 2018; 5:eN-MNT-0266-18. [PMID: 30627639 PMCID: PMC6325541 DOI: 10.1523/eneuro.0266-18.2018] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 10/18/2018] [Accepted: 10/28/2018] [Indexed: 11/21/2022] Open
Abstract
Microglia are dynamic immune cells of the central nervous system, and their morphology is commonly used as a readout of cellular function. However, current morphological analysis techniques rely on either tracing of cells or two-dimensional projection analysis, which are time-consuming, subject to bias, and may ignore important three-dimensional (3D) information. Therefore, we have created 3DMorph, a MATLAB-based script that analyzes microglial morphology from 3D data. The program initially requires input of threshold levels, cell size expectations, and preferred methods of skeletonization. This makes 3DMorph easily scalable and adaptable to different imaging parameters or cell types. After these settings are defined, the program is completely automatic and can batch process files without user input. Output data includes cell volume, territorial volume, branch length, number of endpoints and branch points, and average distance between cells. We show that 3DMorph is accurate compared to manual tracing, with significantly decreased user input time. Importantly, 3DMorph is capable of processing in vivo microglial morphology, as well as other 3D branching cell types, from mouse cranial windows or acute hippocampal slices. Therefore, we present a novel, user-friendly, scalable, and semiautomatic method of analyzing cell morphology in 3 dimensions. This method should improve the accuracy of cell measurements, remove user bias between conditions, increase reproducibility between experimenters and labs, and reduce user input time. We provide this open source code on GitHub so that it is free and accessible to all investigators.
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153
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Bishop JH, Shpaner M, Kubicki A, Clements S, Watts R, Naylor MR. Structural network differences in chronic muskuloskeletal pain: Beyond fractional anisotropy. Neuroimage 2018; 182:441-455. [DOI: 10.1016/j.neuroimage.2017.12.021] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 11/29/2017] [Accepted: 12/10/2017] [Indexed: 12/13/2022] Open
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154
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Abdel-Haq R, Schlachetzki JCM, Glass CK, Mazmanian SK. Microbiome-microglia connections via the gut-brain axis. J Exp Med 2018; 216:41-59. [PMID: 30385457 PMCID: PMC6314531 DOI: 10.1084/jem.20180794] [Citation(s) in RCA: 257] [Impact Index Per Article: 42.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2018] [Revised: 07/08/2018] [Accepted: 10/03/2018] [Indexed: 12/12/2022] Open
Abstract
A role for the gut microbiome in facilitating microglial maturation and shaping microglial physiology has emerged in recent years. This review highlights evidence demonstrating the various mechanisms by which the gut microbiota can influence microglia in both homeostatic and disease conditions. Microglia, the resident immune cells in the brain, are essential for modulating neurogenesis, influencing synaptic remodeling, and regulating neuroinflammation by surveying the brain microenvironment. Microglial dysfunction has been implicated in the onset and progression of several neurodevelopmental and neurodegenerative diseases; however, the multitude of factors and signals influencing microglial activity have not been fully elucidated. Microglia not only respond to local signals within the brain but also receive input from the periphery, including the gastrointestinal (GI) tract. Recent preclinical findings suggest that the gut microbiome plays a pivotal role in regulating microglial maturation and function, and altered microbial community composition has been reported in neurological disorders with known microglial involvement in humans. Collectively, these findings suggest that bidirectional crosstalk between the gut and the brain may influence disease pathogenesis. Herein, we discuss recent studies showing a role for the gut microbiome in modulating microglial development and function in homeostatic and disease conditions and highlight possible future research to develop novel microbial treatments for disorders of the brain.
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Affiliation(s)
- Reem Abdel-Haq
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA
| | | | - Christopher K Glass
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA
| | - Sarkis K Mazmanian
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA
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155
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Pandey GN, Rizavi HS, Zhang H, Bhaumik R, Ren X. Abnormal protein and mRNA expression of inflammatory cytokines in the prefrontal cortex of depressed individuals who died by suicide. J Psychiatry Neurosci 2018; 43:376-385. [PMID: 30371993 PMCID: PMC6203549 DOI: 10.1503/jpn.170192] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Depression and stress are major risk factors for suicidal behaviour, and some studies show abnormalities of proinflammatory cytokines in the serum and cerebrospinal fluid (CSF) of depressed and suicidal patients. However, it is not clear if similar abnormalities of cytokines are present in the brain of suicidal and depressed patients. METHODS We therefore determined the mRNA (using realtime polymerase chain reaction) and protein (using enzyme-linked immunosorbent assay and Western Blot) expression levels of interleukin (IL)-1β, IL-6, tumour necrosis factor (TNF)-α, lymphotoxin A, lymphotoxin B, IL-8, IL-10 and IL-13 in the prefrontal cortex (PFC) obtained from 24 depressed individuals who died by suicide and 24 nonpsychiatric controls. RESULTS We observed that the mRNA and protein levels of IL-1β, IL-6, TNF-α, and lymphotoxin A were significantly increased, and levels of anti-inflammatory cytokine IL-10, and of IL-1 receptor antagonist (IL-1RA) were significantly decreased in the PFC of depressed individuals who died by suicide compared with controls. There were no significant differences in the protein and mRNA levels of IL-8 and IL-13 in the PFC. LIMITATIONS The main limitation of this study is that some of the suicide group had been taking antidepressant medication at the time of death. CONCLUSION Our results suggest that alterations of cytokines may be associated with the pathophysiology of depressed suicide and there may be an imbalance between pro- and anti-inflammatory cytokines in people who die by suicide. The causes of these increases in the brain of people who die by suicide, therefore, need to be investigated further.
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Affiliation(s)
- Ghanshyam N. Pandey
- From the Department of Psychiatry, University of Illinois at Chicago, Chicago, Ill., USA
| | - Hooriyah S. Rizavi
- From the Department of Psychiatry, University of Illinois at Chicago, Chicago, Ill., USA
| | - Hui Zhang
- From the Department of Psychiatry, University of Illinois at Chicago, Chicago, Ill., USA
| | - Runa Bhaumik
- From the Department of Psychiatry, University of Illinois at Chicago, Chicago, Ill., USA
| | - Xinguo Ren
- From the Department of Psychiatry, University of Illinois at Chicago, Chicago, Ill., USA
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156
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Effects of craniopharyngioma cyst fluid on neurons and glial cells cultured from rat brain hypothalamus. J Chem Neuroanat 2018; 94:93-101. [PMID: 30339791 DOI: 10.1016/j.jchemneu.2018.10.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Revised: 10/14/2018] [Accepted: 10/15/2018] [Indexed: 11/20/2022]
Abstract
Craniopharyngiomas (CPs) are rare, epithelial tumors of the central nervous system (CNS) that could lead to manifestation of multiple post-operative symptoms, ranging from hormonal imbalance to obesity, diabetes, visual, neurological and neurocognitive impairments. CP is more frequent in children, and has been reported in middle aged adults as well. In fact, arterial laceration and/or brain stroke which may occur following the removal of some CPs is mainly due to calcification of that CPs along with strong attachments to the blood vessels. The dense oily fluid content of CPs is reported to cause brain tissue damage, demyelination and axonal loss in the hypothalamus; however, its exact effect on different cell types of CNS is still unexplored. In this study, we have collected CP cyst fluid (CCF) from mostly young patients during surgical removal and exposed it 9-10 days in vitro to the primary cultures derived from rat brain hypothalamus for 48 h. A gradual decline in cell viability was noted with increasing concentration of CCF. Moreover, a distinct degenerative morphological transformation was observed in neurons and glial cells, including appearance of blebbing and overall reduction of the cell volume. Further, enhanced expression of Caspase-3 in neurons and glial cells exposed to CCF by immunofluorescence imaging, supported by Western blot experiment suggest CCF induced apoptosis of hypothalamic cells in culture. In this study, we have demonstrated the deleterious effects of the cyst fluid on various cell types within the tumors originating region of the brain and its surroundings for the first time. Taken together, this finding could be beneficial towards identifying the region specific toxic effects of the cyst fluid and its underlying mechanism.
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157
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Polis B, Srikanth KD, Elliott E, Gil-Henn H, Samson AO. L-Norvaline Reverses Cognitive Decline and Synaptic Loss in a Murine Model of Alzheimer's Disease. Neurotherapeutics 2018; 15:1036-1054. [PMID: 30288668 PMCID: PMC6277292 DOI: 10.1007/s13311-018-0669-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The urea cycle is strongly implicated in the pathogenesis of Alzheimer's disease (AD). Arginase-I (ARGI) accumulation at sites of amyloid-beta (Aβ) deposition is associated with L-arginine deprivation and neurodegeneration. An interaction between the arginase II (ARGII) and mTOR-ribosomal protein S6 kinase β-1 (S6K1) pathways promotes inflammation and oxidative stress. In this study, we treated triple-transgenic (3×Tg) mice exhibiting increased S6K1 activity and wild-type (WT) mice with L-norvaline, which inhibits both arginase and S6K1. The acquisition of spatial memory was significantly improved in the treated 3×Tg mice, and the improvement was associated with a substantial reduction in microgliosis. In these mice, increases in the density of dendritic spines and expression levels of neuroplasticity-related proteins were followed by a decline in the levels of Aβ toxic oligomeric and fibrillar species in the hippocampus. The findings point to an association of local Aβ-driven and immune-mediated responses with altered L-arginine metabolism, and they suggest that arginase and S6K1 inhibition by L-norvaline may delay the progression of AD.
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Affiliation(s)
- Baruh Polis
- Drug Discovery Laboratory, The Azrieli Faculty of Medicine, Bar-Ilan University, 1311502, Safed, Israel.
- Laboratory of Cell Migration and Invasion, The Azrieli Faculty of Medicine, Bar-Ilan University, 1311502, Safed, Israel.
| | - Kolluru D Srikanth
- Laboratory of Cell Migration and Invasion, The Azrieli Faculty of Medicine, Bar-Ilan University, 1311502, Safed, Israel
- Laboratory of Molecular and Behavioral Neuroscience, The Azrieli Faculty of Medicine, Bar-Ilan University, 8th Henrietta Szold Street, P.O. Box 1589, 1311502, Safed, Israel
| | - Evan Elliott
- Laboratory of Molecular and Behavioral Neuroscience, The Azrieli Faculty of Medicine, Bar-Ilan University, 8th Henrietta Szold Street, P.O. Box 1589, 1311502, Safed, Israel
| | - Hava Gil-Henn
- Laboratory of Cell Migration and Invasion, The Azrieli Faculty of Medicine, Bar-Ilan University, 1311502, Safed, Israel
| | - Abraham O Samson
- Drug Discovery Laboratory, The Azrieli Faculty of Medicine, Bar-Ilan University, 1311502, Safed, Israel
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158
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Oleoylethanolamide treatment reduces neurobehavioral deficits and brain pathology in a mouse model of Gulf War Illness. Sci Rep 2018; 8:12921. [PMID: 30150699 PMCID: PMC6110778 DOI: 10.1038/s41598-018-31242-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Accepted: 08/15/2018] [Indexed: 12/12/2022] Open
Abstract
There are nearly 250,000 Gulf War (GW) veterans who suffer from Gulf War Illness (GWI), a multi-symptom condition that remains untreatable. The main objective was to determine if targeting peroxisomal function could be of therapeutic value in GWI. We performed a pilot study that showed accumulation of very long chain fatty acids (VLCFA), which are metabolized in peroxisomes, in plasma from veterans with GWI. We then examined if targeting peroxisomal β-oxidation with oleoylethanolamide (OEA) restores these lipids to the normal levels and mitigates neuroinflammation and neurobehavioral deficits in a well-established mouse model of GWI. In GWI mice, treatment with OEA corresponded with cognitive benefits and reduced fatigue and disinhibition-like behavior in GWI mice. Biochemical and molecular analysis of the brain tissue showed reduced astroglia and microglia staining, decreased levels of chemokines and cytokines, and decreased NFκB phosphorylation. Treatment with OEA reduced accumulation of peroxisome specific VLCFA in the brains of GWI mice. These studies further support the translational value of targeting peroxisomes. We expect that OEA may be a potential therapy for treating neurobehavioral symptoms and the underlying lipid dysfunction and neuroinflammation associated with GWI. Oleoylethanolamide is available as a dietary supplement, making it appealing for human translational studies.
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159
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Postnatal Development of Microglia-Like Cells in Mouse Cochlea. Neural Plast 2018; 2018:1970150. [PMID: 30154835 PMCID: PMC6091412 DOI: 10.1155/2018/1970150] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Revised: 05/09/2018] [Accepted: 07/09/2018] [Indexed: 12/20/2022] Open
Abstract
Microglial cells are involved in surveillance and cleaning of the central nervous system. Recently, microglial-like cells (MLC) have been found in an adult cochlea and investigated for their role in cochlear inflammation. The presence and potential roles of MLCs during the development of the cochlea, however, remain unclear. In this study, immunostaining was performed using the MLC-specific marker IBA1 to characterize the presence, distribution, and morphology of MLCs in the developing cochlea. From P0 to P14, MLCs were present in a variety of cochlear regions including the modiolus, spiral lamina, spiral ganglion, spiral ligament, and the organ of Corti. Interestingly, the overall number of MLCs in a mouse cochlea steadily increased since P0, peaks at P5, then gradually decreased from P5 to P14. In the spiral ligament, the distribution of the MLCs trends to shift from the type I/II fibrocyte-rich regions to the type III/IV fibrocyte-rich regions during the course of cochlear development, accompanied by the morphological changes of MLCs from the amoeboid, activated form to the ramified, quiescent form. Our results suggested that MLCs experience drastic morphological and distributional changes during postnatal cochlear development, which may play a role in the maturing and remodeling of the cochlea.
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160
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Lee SW, Gajavelli S, Spurlock MS, Andreoni C, de Rivero Vaccari JP, Bullock MR, Keane RW, Dietrich WD. Microglial Inflammasome Activation in Penetrating Ballistic-Like Brain Injury. J Neurotrauma 2018; 35:1681-1693. [PMID: 29439605 PMCID: PMC6016174 DOI: 10.1089/neu.2017.5530] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Penetrating traumatic brain injury (PTBI) is a significant cause of death and disability in the United States. Inflammasomes are one of the key regulators of the interleukin (IL)-1β mediated inflammatory responses after traumatic brain injury. However, the contribution of inflammasome signaling after PTBI has not been determined. In this study, adult male Sprague-Dawley rats were subjected to sham procedures or penetrating ballistic-like brain injury (PBBI) and sacrificed at various time-points. Tissues were assessed by immunoblot analysis for expression of IL-1β, IL-18, and components of the inflammasome: apoptosis-associated speck-like protein containing a caspase-activation and recruitment domain (ASC), caspase-1, X-linked inhibitor of apoptosis protein (XIAP), nucleotide-binding oligomerization domain (NOD)-like receptor protein 3 (NLRP3), and gasdermin-D (GSDMD). Specific cell types expressing inflammasome proteins also were evaluated immunohistochemically and assessed quantitatively. After PBBI, expression of IL-1β, IL-18, caspase-1, ASC, XIAP, and NLRP3 peaked around 48 h. Brain protein lysates from PTBI animals showed pyroptosome formation evidenced by ASC laddering, and also contained increased expression of GSDMD at 48 h after injury. ASC-positive immunoreactive neurons within the perilesional cortex were observed at 24 h. At 48 h, ASC expression was concentrated in morphologically activated cortical microglia. This expression of ASC in activated microglia persisted until 12 weeks following PBBI. This is the first report of inflammasome activation after PBBI. Our results demonstrate cell-specific patterns of inflammasome activation and pyroptosis predominantly in microglia, suggesting a sustained pro-inflammatory state following PBBI, thus offering a therapeutic target for this type of brain injury.
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Affiliation(s)
- Stephanie W. Lee
- Department of Neurological Surgery, the Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, Florida
| | - Shyam Gajavelli
- Department of Neurological Surgery, the Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, Florida
| | - Markus S. Spurlock
- Department of Neurological Surgery, the Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, Florida
| | - Cody Andreoni
- Department of Neurological Surgery, the Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, Florida
| | - Juan Pablo de Rivero Vaccari
- Department of Neurological Surgery, the Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, Florida
| | - M. Ross Bullock
- Department of Neurological Surgery, the Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, Florida
| | - Robert W. Keane
- Department of Neurological Surgery, the Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, Florida
- Department of Physiology and Biophysics, University of Miami Miller School of Medicine, Miami, Florida
| | - W. Dalton Dietrich
- Department of Neurological Surgery, the Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, Florida
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161
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Vallejo-Giraldo C, Krukiewicz K, Calaresu I, Zhu J, Palma M, Fernandez-Yague M, McDowell B, Peixoto N, Farid N, O'Connor G, Ballerini L, Pandit A, Biggs MJP. Attenuated Glial Reactivity on Topographically Functionalized Poly(3,4-Ethylenedioxythiophene):P-Toluene Sulfonate (PEDOT:PTS) Neuroelectrodes Fabricated by Microimprint Lithography. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2018; 14:e1800863. [PMID: 29862640 DOI: 10.1002/smll.201800863] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2018] [Revised: 04/17/2018] [Indexed: 06/08/2023]
Abstract
Following implantation, neuroelectrode functionality is susceptible to deterioration via reactive host cell response and glial scar-induced encapsulation. Within the neuroengineering community, there is a consensus that the induction of selective adhesion and regulated cellular interaction at the tissue-electrode interface can significantly enhance device interfacing and functionality in vivo. In particular, topographical modification holds promise for the development of functionalized neural interfaces to mediate initial cell adhesion and the subsequent evolution of gliosis, minimizing the onset of a proinflammatory glial phenotype, to provide long-term stability. Herein, a low-temperature microimprint-lithography technique for the development of micro-topographically functionalized neuroelectrode interfaces in electrodeposited poly(3,4-ethylenedioxythiophene):p-toluene sulfonate (PEDOT:PTS) is described and assessed in vitro. Platinum (Pt) microelectrodes are subjected to electrodeposition of a PEDOT:PTS microcoating, which is subsequently topographically functionalized with an ordered array of micropits, inducing a significant reduction in electrode electrical impedance and an increase in charge storage capacity. Furthermore, topographically functionalized electrodes reduce the adhesion of reactive astrocytes in vitro, evident from morphological changes in cell area, focal adhesion formation, and the synthesis of proinflammatory cytokines and chemokine factors. This study contributes to the understanding of gliosis in complex primary mixed cell cultures, and describes the role of micro-topographically modified neural interfaces in the development of stable microelectrode interfaces.
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Affiliation(s)
- Catalina Vallejo-Giraldo
- CÚRAM-Centre for Research in Medical Devices-Galway, Biosciences Research Building, 118 Corrib Village, Newcastle, Galway, H91 D577, Ireland
| | - Katarzyna Krukiewicz
- CÚRAM-Centre for Research in Medical Devices-Galway, Biosciences Research Building, 118 Corrib Village, Newcastle, Galway, H91 D577, Ireland
- Department of Physical Chemistry and Technology of Polymers, Silesian University of Technology, Gliwice, 44-100, Poland
| | - Ivo Calaresu
- Scuola Internazionale Superiore di Studi Avanzati (SISSA), Via Bonomea, 265, 34136, Trieste, Italy
| | - Jingyuan Zhu
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London, E14NS, UK
| | - Matteo Palma
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London, E14NS, UK
| | - Marc Fernandez-Yague
- CÚRAM-Centre for Research in Medical Devices-Galway, Biosciences Research Building, 118 Corrib Village, Newcastle, Galway, H91 D577, Ireland
| | - BenjaminW McDowell
- Department of Electrical and Computer Engineering, George Mason University, 4400 University Drive, MS-1G5 Fairfax, VA, 22030, USA
| | - Nathalia Peixoto
- Department of Electrical and Computer Engineering, George Mason University, 4400 University Drive, MS-1G5 Fairfax, VA, 22030, USA
| | - Nazar Farid
- School of Physics, National University of Ireland, Galway, University Road, Galway, H91 CF50, Ireland
| | - Gerard O'Connor
- School of Physics, National University of Ireland, Galway, University Road, Galway, H91 CF50, Ireland
| | - Laura Ballerini
- Scuola Internazionale Superiore di Studi Avanzati (SISSA), Via Bonomea, 265, 34136, Trieste, Italy
| | - Abhay Pandit
- CÚRAM-Centre for Research in Medical Devices-Galway, Biosciences Research Building, 118 Corrib Village, Newcastle, Galway, H91 D577, Ireland
| | - Manus Jonathan Paul Biggs
- CÚRAM-Centre for Research in Medical Devices-Galway, Biosciences Research Building, 118 Corrib Village, Newcastle, Galway, H91 D577, Ireland
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162
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Granado N, Ares-Santos S, Tizabi Y, Moratalla R. Striatal Reinnervation Process after Acute Methamphetamine-Induced Dopaminergic Degeneration in Mice. Neurotox Res 2018; 34:627-639. [PMID: 29934756 DOI: 10.1007/s12640-018-9925-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 05/28/2018] [Accepted: 06/07/2018] [Indexed: 01/03/2023]
Abstract
Methamphetamine (METH), an amphetamine derivate, may increase the risk of developing Parkinson's disease (PD). Human and animal studies have shown that METH produces persistent dopaminergic neurotoxicity in the nigrostriatal pathway, despite initial partial recovery. To determine the processes leading to early compensation, we studied the detailed morphology and distribution of tyrosine hydroxylase immunoreactive fibers (TH-ir) classified by their thickness (types I-IV) before and after METH. Applying three established neurotoxic regimens of METH: single high dose (1 × 30 mg/kg), multiple lower doses (3 × 5 mg/kg) or (3 × 10 mg/kg), we show that METH primarily damages type I fibers (the thinner ones), and to a much lesser extend types II-IV fibers including sterile axons. The striatal TH terminal partial recovery process, consisting of a progressive regrowth increases in types II, III, and IV fibers, demonstrated by co-localization of GAP-43, a sprouting marker, was observed 3 days post-METH treatment. In addition, we demonstrate the presence of growth-cone-like TH-ir structures, indicative of new terminal generation as well as improvement in motor functions after 3 days. A temporal relationship was observed between decreases in TH-expression and increases in silver staining, a marker of degeneration. Striatal regeneration was associated with an increase in astroglia and decrease in microglia expression, suggesting a possible role for the neuroimmune system in regenerative processes. Identification of regenerative compensatory mechanisms in response to neurotoxic agents could point to novel mechanisms in countering the neurotoxicity and/or enhancing the regenerative processes.
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Affiliation(s)
- Noelia Granado
- Instituto Cajal, Consejo Superior de Investigaciones Científicas, CSIC, Avda Dr Arce 37, 28002, Madrid, Spain.,CIBERNED, ISCIII, Madrid, Spain
| | - Sara Ares-Santos
- Instituto Cajal, Consejo Superior de Investigaciones Científicas, CSIC, Avda Dr Arce 37, 28002, Madrid, Spain.,CIBERNED, ISCIII, Madrid, Spain
| | - Yousef Tizabi
- Department of Pharmacology, Howard University College of Medicine, Washington DC, USA
| | - Rosario Moratalla
- Instituto Cajal, Consejo Superior de Investigaciones Científicas, CSIC, Avda Dr Arce 37, 28002, Madrid, Spain. .,CIBERNED, ISCIII, Madrid, Spain.
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163
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Sun J, Pan X, Christiansen LI, Yuan XL, Skovgaard K, Chatterton DEW, Kaalund SS, Gao F, Sangild PT, Pankratova S. Necrotizing enterocolitis is associated with acute brain responses in preterm pigs. J Neuroinflammation 2018; 15:180. [PMID: 29885660 PMCID: PMC5994241 DOI: 10.1186/s12974-018-1201-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 05/14/2018] [Indexed: 12/24/2022] Open
Abstract
Background Necrotizing enterocolitis (NEC) is an acute gut inflammatory disorder that occurs in preterm infants in the first weeks after birth. Infants surviving NEC often show impaired neurodevelopment. The mechanisms linking NEC lesions with later neurodevelopment are poorly understood but may include proinflammatory signaling in the immature brain. Using preterm pigs as a model for preterm infants, we hypothesized that severe intestinal NEC lesions are associated with acute effects on the developing hippocampus. Methods Cesarean-delivered preterm pigs (n = 117) were reared for 8 days and spontaneously developed variable severity of NEC lesions. Neonatal arousal, physical activity, and in vitro neuritogenic effects of cerebrospinal fluid (CSF) were investigated in pigs showing NEC lesions in the colon (Co-NEC) or in the small intestine (Si-NEC). Hippocampal transcriptome analysis and qPCR were used to assess gene expressions and their relation to biological processes, including neuroinflammation, and neural plasticity. Microglia activation was quantified by stereology. The neuritogenic response to selected proteins was investigated in primary cultures of hippocampal neurons. Results NEC development rapidly reduced the physical activity of pigs, especially when lesions occurred in the small intestine. Si-NEC and Co-NEC were associated with 27 and 12 hippocampal differentially expressed genes (DEGs), respectively. These included genes related to neuroinflammation (i.e., S100A8, S100A9, IL8, IL6, MMP8, SAA, TAGLN2) and hypoxia (i.e., PDK4, IER3, TXNIP, AGER), and they were all upregulated in Si-NEC pigs. Genes related to protection against oxidative stress (HBB, ALAS2) and oligodendrocytes (OPALIN) were downregulated in Si-NEC pigs. CSF collected from NEC pigs promoted neurite outgrowth in vitro, and the S100A9 and S100A8/S100A9 proteins may mediate the neuritogenic effects of NEC-related CSF on hippocampal neurons. NEC lesions did not affect total microglial cell number but markedly increased the proportion of Iba1-positive amoeboid microglial cells. Conclusions NEC lesions, especially when present in the small intestine, are associated with changes to hippocampal gene expression that potentially mediate neuroinflammation and disturbed neural circuit formation via enhanced neuronal differentiation. Early brain-protective interventions may be critical for preterm infants affected by intestinal NEC lesions to reduce their later neurological dysfunctions. Electronic supplementary material The online version of this article (10.1186/s12974-018-1201-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jing Sun
- Comparative Pediatrics and Nutrition, Department of Veterinary and Animal Sciences, University of Copenhagen, DK-1870, Frederiksberg C, Denmark
| | - Xiaoyu Pan
- Comparative Pediatrics and Nutrition, Department of Veterinary and Animal Sciences, University of Copenhagen, DK-1870, Frederiksberg C, Denmark
| | - Line I Christiansen
- Comparative Pediatrics and Nutrition, Department of Veterinary and Animal Sciences, University of Copenhagen, DK-1870, Frederiksberg C, Denmark
| | - Xiao-Long Yuan
- Comparative Pediatrics and Nutrition, Department of Veterinary and Animal Sciences, University of Copenhagen, DK-1870, Frederiksberg C, Denmark
| | - Kerstin Skovgaard
- Department of Biotechnology and Biomedicine, Technical University of Denmark, DK-2800, Kgs. Lyngby, Denmark
| | - Dereck E W Chatterton
- Comparative Pediatrics and Nutrition, Department of Veterinary and Animal Sciences, University of Copenhagen, DK-1870, Frederiksberg C, Denmark.,Department of Food Science, University of Copenhagen, DK-1958, Frederiksberg C, Denmark
| | - Sanne S Kaalund
- Research Laboratory for Stereology and Neuroscience, Bispebjerg-Frederiksberg Hospitals, DK-2400, Copenhagen, Denmark
| | - Fei Gao
- Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, 518000, Shenzhen, China
| | - Per T Sangild
- Comparative Pediatrics and Nutrition, Department of Veterinary and Animal Sciences, University of Copenhagen, DK-1870, Frederiksberg C, Denmark. .,Department of Pediatrics and Adolescent Medicine, Rigshospitalet, Blegdamsvej 9, DK-2100, Copenhagen, Denmark.
| | - Stanislava Pankratova
- Department of Pediatrics and Adolescent Medicine, Rigshospitalet, Blegdamsvej 9, DK-2100, Copenhagen, Denmark. .,Laboratory of Neural Plasticity, Department of Neuroscience, University of Copenhagen, DK-2200, Copenhagen, Denmark.
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164
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Wang J, Xing H, Wan L, Jiang X, Wang C, Wu Y. Treatment targets for M2 microglia polarization in ischemic stroke. Biomed Pharmacother 2018; 105:518-525. [PMID: 29883947 DOI: 10.1016/j.biopha.2018.05.143] [Citation(s) in RCA: 89] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2018] [Revised: 05/25/2018] [Accepted: 05/28/2018] [Indexed: 02/06/2023] Open
Abstract
As the first line of defense in the nervous system, resident microglia are the predominant immune cells in the brain. In diseases of the central nervous system such as stroke, Alzheimer's disease, and Parkinson's disease, they often cause inflammation or phagocytosis; however, some studies have found that despite the current controversy over M1, M2 polarization could be beneficial. Ischemic stroke is the third most common cause of death in humans. Patients who survive an ischemic stroke might experience a clear decline in their quality of life, owing to conditions such as hemiplegic paralysis and aphasia. After stroke, the activated microglia become a double-edged sword, with distinct phenotypic changes to the deleterious M1 and neuroprotective M2 types. Therefore, methods for promoting the differentiation of microglia into the M2 polarized form to alleviate harmful reactions after stroke have become a topic of interest in recent years. Subsequently, the discovery of new drugs related to M2 polarization has enabled the realization of targeted therapies. In the present review, we discussed the neuroprotective effects of microglia M2 polarization and the potential mechanisms and drugs by which microglia can be transformed into the M2 polarized type after stroke.
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Affiliation(s)
- Ji Wang
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Hongyi Xing
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Lin Wan
- The Children's Hospital of Soochow, Jiangsu, Hematology and Oncology, China
| | - Xingjun Jiang
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Chen Wang
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Yan Wu
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China.
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165
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Zhang C, Brandon NR, Koper K, Tang P, Xu Y, Dou H. Invasion of Peripheral Immune Cells into Brain Parenchyma after Cardiac Arrest and Resuscitation. Aging Dis 2018; 9:412-425. [PMID: 29896429 PMCID: PMC5988596 DOI: 10.14336/ad.2017.0926] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Accepted: 09/26/2017] [Indexed: 12/12/2022] Open
Abstract
Although a direct link has long been suspected between systemic immune responses and neuronal injuries after stroke, it is unclear which immune cells play an important role. A question remains as to whether the blood brain barrier (BBB) is transiently disrupted after circulatory arrest to allow peripheral immune cells to enter brain parenchyma. Here, we developed a clinically relevant cardiac arrest and resuscitation model in mice to investigate the BBB integrity using noninvasive magnetic resonance imaging. Changes in immune signals in the brain and periphery were assayed by immunohistochemistry and flow cytometry. Quantitative variance maps from T1-weighted difference images before and after blood-pool contrast clearance revealed BBB disruptions immediately after resuscitation and one day after reperfusion. Time profiles of hippocampal CA1 neuronal injuries correlated with the morphological changes of microglia activation. Cytotoxic T cells, CD11b+CD11c+ dendritic cells, and CD11b+CD45+hi monocytes and macrophages were significantly increased in the brain three days after cardiac arrest and resuscitation, suggesting direct infiltration of these cells following the BBB disruption. Importantly, these immune cell changes were coupled with a parallel increase in the same subset of immune cell populations in the bone marrow and blood. We conclude that neurovascular breakdown during the initial reperfusion phase contributes to the systemic immune cell invasion and subsequent neuropathogenesis affecting the long-term outcome after cardiac arrest and resuscitation.
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Affiliation(s)
| | | | | | - Pei Tang
- 1Departments of Anesthesiology.,2Pharmacology and Chemical Biology.,3Computational and Systems Biology
| | - Yan Xu
- 1Departments of Anesthesiology.,2Pharmacology and Chemical Biology.,4Physics and Astronomy, and.,5Structural Biology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Huanyu Dou
- 6Department of Biomedical Sciences, Paul L. Foster School of Medicine, and.,7Graduate School of Biomedical Sciences, Texas Tech University Health Sciences Center, El Paso, TX 79905, USA
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166
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Rusconi R, Ulusoy A, Aboutalebi H, Di Monte DA. Long-lasting pathological consequences of overexpression-induced α-synuclein spreading in the rat brain. Aging Cell 2018; 17. [PMID: 29383832 PMCID: PMC5847868 DOI: 10.1111/acel.12727] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/28/2017] [Indexed: 01/21/2023] Open
Abstract
Increased expression of α‐synuclein can initiate its long‐distance brain transfer, representing a potential mechanism for pathology spreading in age‐related synucleinopathies, such as Parkinson's disease. In this study, the effects of overexpression‐induced α‐synuclein transfer were assessed over a 1‐year period after injection of viral vectors carrying human α‐synuclein DNA into the rat vagus nerve. This treatment causes targeted overexpression within neurons in the dorsal medulla oblongata and subsequent diffusion of the exogenous protein toward more rostral brain regions. Protein advancement and accumulation in pontine, midbrain, and forebrain areas were contingent upon continuous overexpression, because death of transduced medullary neurons resulted in cessation of spreading. Lack of sustained spreading did not prevent the development of long‐lasting pathological changes. Particularly remarkable were findings in the locus coeruleus, a pontine nucleus with direct connections to the dorsal medulla oblongata and greatly affected by overexpression‐induced transfer in this model. Data revealed progressive degeneration of catecholaminergic neurons that proceeded long beyond the time of spreading cessation. Neuronal pathology in the locus coeruleus was accompanied by pronounced microglial activation and, at later times, astrocytosis. Interestingly, microglial activation was also featured in another region reached by α‐synuclein transfer, the central amygdala, even in the absence of frank neurodegeneration. Thus, overexpression‐induced spreading, even if temporary, causes long‐lasting pathological consequences in brain regions distant from the site of overexpression but anatomically connected to it. Neurodegeneration may be a consequence of severe protein burden, whereas even a milder α‐synuclein accumulation in tissues affected by protein transfer could induce sustained microglial activation.
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Affiliation(s)
| | - Ayse Ulusoy
- German Center for Neurodegenerative Diseases (DZNE); Bonn Germany
| | - Helia Aboutalebi
- German Center for Neurodegenerative Diseases (DZNE); Bonn Germany
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167
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Coburn JL, Cole TB, Dao KT, Costa LG. Acute exposure to diesel exhaust impairs adult neurogenesis in mice: prominence in males and protective effect of pioglitazone. Arch Toxicol 2018. [PMID: 29523932 DOI: 10.1007/s00204-018-2180-5] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Adult neurogenesis is the process by which neural stem cells give rise to new functional neurons in specific regions of the adult brain, a process that occurs throughout life. Significantly, neurodegenerative and psychiatric disorders present suppressed neurogenesis, activated microglia, and neuroinflammation. Traffic-related air pollution has been shown to adversely affect the central nervous system. As the cardinal effects of air pollution exposure are microglial activation, and ensuing oxidative stress and neuroinflammation, we investigated whether acute exposures to diesel exhaust (DE) would inhibit adult neurogenesis in mice. Mice were exposed for 6 h to DE at a PM2.5 concentration of 250-300 μg/m3, followed by assessment of adult neurogenesis in the hippocampal subgranular zone (SGZ), the subventricular zone (SVZ), and olfactory bulb (OB). DE impaired cellular proliferation in the SGZ and SVZ in males, but not females. DE reduced adult neurogenesis, with male mice showing fewer new neurons in the SGZ, SVZ, and OB, and females showing fewer new neurons only in the OB. To assess whether blocking microglial activation protected against DE-induced suppression of adult hippocampal neurogenesis, male mice were pre-treated with pioglitazone (PGZ) prior to DE exposure. The effects of DE exposure on microglia, as well as neuroinflammation and oxidative stress, were reduced by PGZ. PGZ also antagonized DE-induced suppression of neurogenesis in the SGZ. These results suggest that DE exposure impairs adult neurogenesis in a sex-dependent manner, by a mechanism likely to involve microglia activation and neuroinflammation.
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Affiliation(s)
- Jacki L Coburn
- Department of Environmental and Occupational Health Sciences, University of Washington, 4225 Roosevelt, Suite No. 100, Seattle, WA, 98105, USA
| | - Toby B Cole
- Department of Environmental and Occupational Health Sciences, University of Washington, 4225 Roosevelt, Suite No. 100, Seattle, WA, 98105, USA.
- Center on Human Development and Disability, University of Washington, Seattle, WA, USA.
| | - Khoi T Dao
- Department of Environmental and Occupational Health Sciences, University of Washington, 4225 Roosevelt, Suite No. 100, Seattle, WA, 98105, USA
| | - Lucio G Costa
- Department of Environmental and Occupational Health Sciences, University of Washington, 4225 Roosevelt, Suite No. 100, Seattle, WA, 98105, USA.
- Department of Medicine and Surgery, University of Parma, Parma, Italy.
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168
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Liu W, Molnar M, Garnham C, Benav H, Rask-Andersen H. Macrophages in the Human Cochlea: Saviors or Predators-A Study Using Super-Resolution Immunohistochemistry. Front Immunol 2018; 9:223. [PMID: 29487598 PMCID: PMC5816790 DOI: 10.3389/fimmu.2018.00223] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Accepted: 01/26/2018] [Indexed: 12/20/2022] Open
Abstract
The human inner ear, which is segregated by a blood/labyrinth barrier, contains resident macrophages [CD163, ionized calcium-binding adaptor molecule 1 (IBA1)-, and CD68-positive cells] within the connective tissue, neurons, and supporting cells. In the lateral wall of the cochlea, these cells frequently lie close to blood vessels as perivascular macrophages. Macrophages are also shown to be recruited from blood-borne monocytes to damaged and dying hair cells induced by noise, ototoxic drugs, aging, and diphtheria toxin-induced hair cell degeneration. Precise monitoring may be crucial to avoid self-targeting. Macrophage biology has recently shown that populations of resident tissue macrophages may be fundamentally different from circulating macrophages. We removed uniquely preserved human cochleae during surgery for treating petroclival meningioma compressing the brain stem, after ethical consent. Molecular and cellular characterization using immunofluorescence with antibodies against IBA1, TUJ1, CX3CL1, and type IV collagen, and super-resolution structured illumination microscopy (SR-SIM) were made together with transmission electron microscopy. The super-resolution microscopy disclosed remarkable phenotypic variants of IBA1 cells closely associated with the spiral ganglion cells. Monitoring cells adhered to neurons with “synapse-like” specializations and protrusions. Active macrophages migrated occasionally nearby damaged hair cells. Results suggest that the human auditory nerve is under the surveillance and possible neurotrophic stimulation of a well-developed resident macrophage system. It may be alleviated by the non-myelinated nerve soma partly explaining why, in contrary to most mammals, the human’s auditory nerve is conserved following deafferentiation. It makes cochlear implantation possible, for the advantage of the profoundly deaf. The IBA1 cells may serve additional purposes such as immune modulation, waste disposal, and nerve regeneration. Their role in future stem cell-based therapy needs further exploration.
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Affiliation(s)
- Wei Liu
- Section of Otolaryngology, Department of Surgical Sciences, Uppsala University Hospital, Uppsala, Sweden
| | - Matyas Molnar
- Immunology, Genetics and Pathology - Biovis Platform, Uppsala University, Uppsala, Sweden
| | | | | | - Helge Rask-Andersen
- Head and Neck Surgery, Section of Otolaryngology, Department of Surgical Sciences, Uppsala University Hospital, Uppsala, Sweden
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169
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Truettner JS, Bramlett HM, Dietrich WD. Hyperthermia and Mild Traumatic Brain Injury: Effects on Inflammation and the Cerebral Vasculature. J Neurotrauma 2018; 35:940-952. [PMID: 29108477 DOI: 10.1089/neu.2017.5303] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Mild traumatic brain injury (mTBI) or concussion represents the majority of brain trauma in the United States. The pathophysiology of mTBI is complex and may include both focal and diffuse injury patterns. In addition to altered circuit dysfunction and traumatic axonal injury (TAI), chronic neuroinflammation has also been implicated in the pathophysiology of mTBI. Recently, our laboratory has reported the detrimental effects of mild hyperthermic mTBI in terms of worsening histopathological and behavioral outcomes. To clarify the role of temperature-sensitive neuroinflammatory processes on these consequences, we evaluated the effects of elevated brain temperature (39°C) on altered microglia/macrophage phenotype patterns after mTBI, changes in leukocyte recruitment, and TAI. Sprague-Dawley male rats underwent mild parasagittal fluid-percussion injury under normothermic (37°C) or hyperthermic (39°C) conditions. Cortical and hippocampal regions were analyzed using several cellular and molecular outcome measures. At 24 h, the ratio of iNOS-positive (M1 type phenotype) to arginase-positive (M2 type phenotype) cells after hyperthermic mTBI showed an increase compared with normothermia by flow cytometry. Inflammatory response gene arrays also demonstrated a significant increase in several classes of pro-inflammatory genes with hyperthermia treatment over normothermia. The injury-induced expression of chemokine ligand 2 (Ccl2) and alpha-2-macroglobulin were also increased with hyperthermic mTBI. With western blot analysis, an increase in CD18 and intercellular cell adhesion molecule-1 (ICAM-1) with hyperthermia and a significant increase in Iba1 reactive microglia are reported in the cerebral cortex. Together, these results demonstrate significant differences in the cellular and molecular consequences of raised brain temperature at the time of mTBI. The observed polarization toward a M1-phenotype with mild hyperthermia would be expected to augment chronic inflammatory cascades, sustained functional deficits, and increased vulnerability to secondary insults. Mild elevations in brain temperature may contribute to the more severe and longer lasting consequences of mTBI or concussion reported in some patients.
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Affiliation(s)
- Jessie S Truettner
- Department of Neurological Surgery, The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, Florida
| | - Helen M Bramlett
- Department of Neurological Surgery, The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, Florida
| | - W Dalton Dietrich
- Department of Neurological Surgery, The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, Florida
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170
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Sharma S, Carlson S, Puttachary S, Sarkar S, Showman L, Putra M, Kanthasamy AG, Thippeswamy T. Role of the Fyn-PKCδ signaling in SE-induced neuroinflammation and epileptogenesis in experimental models of temporal lobe epilepsy. Neurobiol Dis 2018; 110:102-121. [PMID: 29197620 PMCID: PMC5753797 DOI: 10.1016/j.nbd.2017.11.008] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2017] [Revised: 11/08/2017] [Accepted: 11/27/2017] [Indexed: 02/07/2023] Open
Abstract
Status epilepticus (SE) induces neuroinflammation and epileptogenesis, but the mechanisms are not yet fully delineated. The Fyn, a non-receptor Src family tyrosine kinase (SFK), and its immediate downstream target, PKCδ are emerging as potential mediators of neuroinflammation. In order to first determine the role of Fyn kinase signaling in SE, we tested the efficacy of a SFK inhibitor, saracatinib (25mg/kg, oral) in C57BL/6J mouse kainate model of acute seizures. Saracatinib pretreatment dampened SE severity and completely prevented mortality. We further utilized fyn-/- and fyn+/+ mice (wildtype control for the fyn-/- mice on same genetic background), and the rat kainate model, treated with saracatinib post-SE, to validate the role of Fyn/SFK in SE and epileptogenesis. We observed significant reduction in SE severity, epileptiform spikes, and electrographic non-convulsive seizures in fyn-/- mice when compared to fyn+/+ mice. Interestingly, significant reductions in phosphorylated pSrc-416 and PKCδ (pPKCδ-507) and naive PKCδ were observed in fyn-/- mice as compared to fyn+/+ mice suggesting that PKCδ signaling is a downstream mediator of Fyn in SE and epileptogenesis. Notably, fyn-/- mice also showed a reduction in key proinflammatory mediators TNF-α, IL-1β, and iNOS mRNA expression; serum IL-6 and IL-12 levels; and nitro-oxidative stress markers such as 4-HNE, gp91phox, and 3-NT in the hippocampus. Immunohistochemistry revealed a significant increase in reactive microgliosis and neurodegeneration in the hippocampus and hilus of dentate gyrus in fyn+/+ mice in contrast to fyn-/- mice. Interestingly, we did not observe upregulation of Fyn in pyramidal neurons of the hippocampus during post-SE in fyn+/+ mice, but it was upregulated in hilar neurons of the dentate gyrus when compared to naïve control. In reactive microglia, both Fyn and PKCδ were persistently upregulated during post-SE suggesting that Fyn-PKCδ may drive neuroinflammation during epileptogenesis. Since disabling the Fyn kinase prior to SE, either by treating with saracatinib or fyn gene knockout, suppressed seizures and the subsequent epileptogenic events, we further tested whether Fyn/SFK inhibition during post-SE modifies epileptogenesis. Telemetry-implanted, SE-induced, rats were treated with saracatinib and continuously monitored for a month. At 2h post-diazepam, the saracatinib (25mg/kg) or the vehicle was administered orally and repeated twice daily for first three days followed by a single dose/day for the next four days. The saracatinib post-treatment prevented epileptogenesis in >50% of the rats and significantly reduced spontaneous seizures and epileptiform spikes in the rest (one animal did not respond) when compared to the vehicle treated group, which had >24 seizures in a month. Collectively, the findings suggest that Fyn/SFK is a potential mediator of epileptogenesis and a therapeutic target to prevent/treat seizures and epileptogenesis.
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Affiliation(s)
- Shaunik Sharma
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames 50011, USA
| | - Steven Carlson
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames 50011, USA
| | - Sreekanth Puttachary
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames 50011, USA
| | - Souvarish Sarkar
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames 50011, USA
| | - Lucas Showman
- W.M. Keck Metabolomics Research Laboratory, Iowa State University, Ames 50011, USA
| | - Marson Putra
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames 50011, USA
| | - Anumantha G Kanthasamy
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames 50011, USA
| | - Thimmasettappa Thippeswamy
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames 50011, USA.
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171
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Lynch CE, Crynen G, Ferguson S, Mouzon B, Paris D, Ojo J, Leary P, Crawford F, Bachmeier C. Chronic cerebrovascular abnormalities in a mouse model of repetitive mild traumatic brain injury. Brain Inj 2018; 30:1414-1427. [PMID: 27834539 DOI: 10.1080/02699052.2016.1219060] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
PRIMARY OBJECTIVE To investigate the status of the cerebrovasculature following repetitive mild traumatic brain injury (r-mTBI). RESEARCH DESIGN TBI is a risk factor for development of various neurodegenerative disorders. A common feature of neurodegenerative disease is cerebrovascular dysfunction which includes alterations in cerebral blood flow (CBF). TBI can result in transient reductions in CBF, with severe injuries often accompanied by varying degrees of vascular pathology post-mortem. However, at this stage, few studies have investigated the cerebrovasculature at chronic time points following repetitive mild brain trauma. METHODS AND PROCEDURES r-mTBI was delivered to wild-type mice (12 months old) twice per week for 3 months and tested for spatial memory deficits (Barnes Maze task) at 1 and 6 months post-injury. At 7 months post-injury CBF was assessed via Laser Doppler Imaging and, following euthanasia, the brain was probed for markers of cerebrovascular dysfunction and inflammation. MAIN OUTCOMES AND RESULTS Memory impairment was identified at 1 month post-injury and persisted as late as 6 months post-injury. Furthermore, significant immunopathological insult, reductions in global CBF and down-regulation of cerebrovascular-associated markers were observed. CONCLUSIONS These results demonstrate impaired cognitive behaviour alongside chronic cerebrovascular dysfunction in a mouse model of repetitive mild brain trauma.
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Affiliation(s)
- Cillian E Lynch
- a The Roskamp Institute , Sarasota , FL , USA.,b The Open University , Department of Life Sciences , Milton Keynes , UK.,c James A. Haley Veteran's Administration Center , Tampa , FL , USA
| | - Gogce Crynen
- a The Roskamp Institute , Sarasota , FL , USA.,b The Open University , Department of Life Sciences , Milton Keynes , UK.,c James A. Haley Veteran's Administration Center , Tampa , FL , USA
| | - Scott Ferguson
- a The Roskamp Institute , Sarasota , FL , USA.,b The Open University , Department of Life Sciences , Milton Keynes , UK.,c James A. Haley Veteran's Administration Center , Tampa , FL , USA
| | - Benoit Mouzon
- a The Roskamp Institute , Sarasota , FL , USA.,b The Open University , Department of Life Sciences , Milton Keynes , UK.,c James A. Haley Veteran's Administration Center , Tampa , FL , USA
| | - Daniel Paris
- a The Roskamp Institute , Sarasota , FL , USA.,b The Open University , Department of Life Sciences , Milton Keynes , UK.,c James A. Haley Veteran's Administration Center , Tampa , FL , USA
| | - Joseph Ojo
- a The Roskamp Institute , Sarasota , FL , USA.,b The Open University , Department of Life Sciences , Milton Keynes , UK.,c James A. Haley Veteran's Administration Center , Tampa , FL , USA
| | - Paige Leary
- a The Roskamp Institute , Sarasota , FL , USA
| | - Fiona Crawford
- a The Roskamp Institute , Sarasota , FL , USA.,b The Open University , Department of Life Sciences , Milton Keynes , UK.,c James A. Haley Veteran's Administration Center , Tampa , FL , USA
| | - Corbin Bachmeier
- a The Roskamp Institute , Sarasota , FL , USA.,b The Open University , Department of Life Sciences , Milton Keynes , UK.,c James A. Haley Veteran's Administration Center , Tampa , FL , USA
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172
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Plastira I, Bernhart E, Goeritzer M, DeVaney T, Reicher H, Hammer A, Lohberger B, Wintersperger A, Zucol B, Graier WF, Kratky D, Malle E, Sattler W. Lysophosphatidic acid via LPA-receptor 5/protein kinase D-dependent pathways induces a motile and pro-inflammatory microglial phenotype. J Neuroinflammation 2017; 14:253. [PMID: 29258556 PMCID: PMC5735906 DOI: 10.1186/s12974-017-1024-1] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Accepted: 12/06/2017] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Extracellular lysophosphatidic acid (LPA) species transmit signals via six different G protein-coupled receptors (LPAR1-6) and are indispensible for brain development and function of the nervous system. However, under neuroinflammatory conditions or brain damage, LPA levels increase, thereby inducing signaling cascades that counteract brain function. We describe a critical role for 1-oleyl-2-hydroxy-sn-glycero-3-phosphate (termed "LPA" throughout our study) in mediating a motile and pro-inflammatory microglial phenotype via LPAR5 that couples to protein kinase D (PKD)-mediated pathways. METHODS Using the xCELLigence system and time-lapse microscopy, we investigated the migrational response of microglial cells. Different M1 and M2 markers were analyzed by confocal microscopy, flow cytometry, and immunoblotting. Using qPCR and ELISA, we studied the expression of migratory genes and quantitated the secretion of pro-inflammatory cytokines and chemokines, respectively. Different transcription factors that promote the regulation of pro-inflammatory genes were analyzed by western blot. Reactive oxygen species (ROS) and nitric oxide (NO) production, phagocytosis, and microglial cytotoxicity were determined using commercially available assay kits. RESULTS LPA induces MAPK family and AKT activation and pro-inflammatory transcription factors' phosphorylation (NF-κB, c-Jun, STAT1, and STAT3) that were inhibited by both LPAR5 and PKD family antagonists. LPA increases migratory capacity, induces secretion of pro-inflammatory cytokines and chemokines and expression of M1 markers, enhances production of ROS and NO by microglia, and augments cytotoxicity of microglial cell-conditioned medium towards neurons. The PKD family inhibitor blunted all of these effects. We propose that interference with this signaling axis could aid in the development of new therapeutic approaches to control neuroinflammation under conditions of overshooting LPA production. CONCLUSIONS In the present study, we show that inflammatory LPA levels increased the migratory response of microglia and promoted a pro-inflammatory phenotype via the LPAR5/PKD axis. Interference with this signaling axis reduced microglial migration, blunted microglial cytotoxicity, and abrogated the expression and secretion of pro-inflammatory mediators.
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Affiliation(s)
- I. Plastira
- 0000 0000 8988 2476grid.11598.34Institute of Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6/6, 8010 Graz, Austria
| | - E. Bernhart
- 0000 0000 8988 2476grid.11598.34Institute of Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6/6, 8010 Graz, Austria
| | - M. Goeritzer
- 0000 0000 8988 2476grid.11598.34Institute of Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6/6, 8010 Graz, Austria ,grid.452216.6BioTechMed-Graz, Graz, Austria
| | - T. DeVaney
- 0000 0000 8988 2476grid.11598.34Institute of Biophysics, Medical University of Graz, Graz, Austria
| | - H. Reicher
- 0000 0000 8988 2476grid.11598.34Institute of Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6/6, 8010 Graz, Austria
| | - A. Hammer
- 0000 0000 8988 2476grid.11598.34Institute of Cell Biology, Histology and Embryology, Medical University of Graz, Graz, Austria
| | - B. Lohberger
- 0000 0000 8988 2476grid.11598.34Department of Orthopedic Surgery, Medical University of Graz, Graz, Austria
| | - A. Wintersperger
- 0000 0000 8988 2476grid.11598.34Institute of Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6/6, 8010 Graz, Austria
| | - B. Zucol
- 0000 0000 8988 2476grid.11598.34Institute of Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6/6, 8010 Graz, Austria
| | - W. F. Graier
- 0000 0000 8988 2476grid.11598.34Institute of Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6/6, 8010 Graz, Austria ,grid.452216.6BioTechMed-Graz, Graz, Austria
| | - D. Kratky
- 0000 0000 8988 2476grid.11598.34Institute of Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6/6, 8010 Graz, Austria ,grid.452216.6BioTechMed-Graz, Graz, Austria
| | - E. Malle
- 0000 0000 8988 2476grid.11598.34Institute of Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6/6, 8010 Graz, Austria
| | - W. Sattler
- 0000 0000 8988 2476grid.11598.34Institute of Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6/6, 8010 Graz, Austria ,grid.452216.6BioTechMed-Graz, Graz, Austria
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173
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Wyatt-Johnson SK, Herr SA, Brewster AL. Status Epilepticus Triggers Time-Dependent Alterations in Microglia Abundance and Morphological Phenotypes in the Hippocampus. Front Neurol 2017; 8:700. [PMID: 29326654 PMCID: PMC5741821 DOI: 10.3389/fneur.2017.00700] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Accepted: 12/06/2017] [Indexed: 12/30/2022] Open
Abstract
Status epilepticus (SE) is defined by the occurrence of prolonged “non-stop” seizures that last for at least 5 min. SE provokes inflammatory responses including the activation of microglial cells, the brain’s resident immune cells, which are thought to contribute to the neuropathology and pathophysiology of epilepsy. Microglia are professional phagocytes that resemble peripheral macrophages. Upon sensing immune disturbances, including SE, microglia become reactive, produce inflammatory cytokines, and alter their actin cytoskeleton to transform from ramified to amoeboid shapes. It is widely known that SE triggers time-dependent microglial expression of pro-inflammatory cytokines that include TNFα and IL-1β. However, less is known in regards to the spatiotemporal progression of the morphological changes, which may help define the extent of microglia reactivity after SE and potential function (surveillance, inflammatory, phagocytic). Therefore, in this study, we used the microglia/macrophage IBA1 marker to identify and count these cells in hippocampi from control rats and at 4 h, 3 days, and 2 weeks after a single episode of pilocarpine-induced SE. We identified, categorized, and counted the IBA1-positive cells with the different morphologies observed after SE in the hippocampal areas CA1, CA3, and dentate gyrus. These included ramified, hypertrophic, bushy, amoeboid, and rod. We found that the ramified phenotype was the most abundant in control hippocampi. In contrast, SE provoked time-dependent changes in the microglial morphology that was characterized by significant increases in the abundance of bushy-shaped cells at 4 h and amoeboid-shaped cells at 3 days and 2 weeks. Interestingly, a significant increase in the number of rod-shaped cells was only evident in the CA1 region at 2 weeks after SE. Taken together, these data suggest that SE triggers time-dependent alterations in the morphology of microglial cells. This detailed description of the spatiotemporal profile of SE-induced microglial morphological changes may help provide insight into their contribution to epileptogenesis.
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Affiliation(s)
- Season K Wyatt-Johnson
- Department of Psychological Sciences, College of Health and Human Sciences, Purdue University, West Lafayette, IN, United States
| | - Seth A Herr
- Department of Psychological Sciences, College of Health and Human Sciences, Purdue University, West Lafayette, IN, United States
| | - Amy L Brewster
- Department of Psychological Sciences, College of Health and Human Sciences, Purdue University, West Lafayette, IN, United States.,Weldon School of Biomedical Engineering, West Lafayette, IN, United States
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174
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Eggen BJL, Boddeke EWGM, Kooistra SM. Regulation of Microglia Identity from an Epigenetic and Transcriptomic Point of View. Neuroscience 2017; 405:3-13. [PMID: 29247774 DOI: 10.1016/j.neuroscience.2017.12.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Revised: 12/05/2017] [Accepted: 12/06/2017] [Indexed: 12/11/2022]
Abstract
Microglia have long been recognized as the endogenous innate immune elements in the central nervous system (CNS) parenchyma. Besides fulfilling local immune-related functions, they provide cross-talk between the CNS and the immune system at large. In the adult CNS, microglia are involved in maintaining brain homeostasis, modulating synaptic transmission and clearance of apoptotic cells. During embryonic development, microglia are responsible for the removal of supernumerary synapses and neurons, and neuronal network formation. The full scale of their potential abilities has been highlighted by improvements in microglia isolation methods, the development of genetically tagged mouse models, advanced imaging technologies and the application of next-generation sequencing in recent years. Genome-wide expression analysis of relatively pure microglia populations from both mouse and human CNS tissues has thereby greatly contributed to our knowledge of their biology; what defines them under homeostatic conditions and how microglia respond to processes like aging and CNS disease? How and to what degree beneficial functions of microglia can be restored in the aged or diseased brain will be the key issue to be addressed in future research.
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Affiliation(s)
- Bart J L Eggen
- Department of Neuroscience, Section Medical Physiology, University of Groningen, University Medical Center Groningen, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
| | - Erik W G M Boddeke
- Department of Neuroscience, Section Medical Physiology, University of Groningen, University Medical Center Groningen, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands
| | - Susanne M Kooistra
- Department of Neuroscience, Section Medical Physiology, University of Groningen, University Medical Center Groningen, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands.
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175
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Maurya SK, Mishra R. Co-Localization and Interaction of Pax5 with Iba1 in Brain of Mice. Cell Mol Neurobiol 2017; 38:919-927. [DOI: 10.1007/s10571-017-0566-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 11/08/2017] [Indexed: 01/05/2023]
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176
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Gama Sosa MA, De Gasperi R, Perez Garcia GS, Sosa H, Searcy C, Vargas D, Janssen PL, Perez GM, Tschiffely AE, Janssen WG, McCarron RM, Hof PR, Haghighi FG, Ahlers ST, Elder GA. Lack of chronic neuroinflammation in the absence of focal hemorrhage in a rat model of low-energy blast-induced TBI. Acta Neuropathol Commun 2017; 5:80. [PMID: 29126430 PMCID: PMC6389215 DOI: 10.1186/s40478-017-0483-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 10/17/2017] [Indexed: 11/10/2022] Open
Abstract
Blast-related traumatic brain injury (TBI) has been a common cause of injury in the recent conflicts in Iraq and Afghanistan. Blast waves can damage blood vessels, neurons, and glial cells within the brain. Acutely, depending on the blast energy, blast wave duration, and number of exposures, blast waves disrupt the blood-brain barrier, triggering microglial activation and neuroinflammation. Recently, there has been much interest in the role that ongoing neuroinflammation may play in the chronic effects of TBI. Here, we investigated whether chronic neuroinflammation is present in a rat model of repetitive low-energy blast exposure. Six weeks after three 74.5-kPa blast exposures, and in the absence of hemorrhage, no significant alteration in the level of microglia activation was found. At 6 weeks after blast exposure, plasma levels of fractalkine, interleukin-1β, lipopolysaccharide-inducible CXC chemokine, macrophage inflammatory protein 1α, and vascular endothelial growth factor were decreased. However, no differences in cytokine levels were detected between blast-exposed and control rats at 40 weeks. In brain, isolated changes were seen in levels of selected cytokines at 6 weeks following blast exposure, but none of these changes was found in both hemispheres or at 40 weeks after blast exposure. Notably, one animal with a focal hemorrhagic tear showed chronic microglial activation around the lesion 16 weeks post-blast exposure. These findings suggest that focal hemorrhage can trigger chronic focal neuroinflammation following blast-induced TBI, but that in the absence of hemorrhage, chronic neuroinflammation is not a general feature of low-level blast injury.
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Affiliation(s)
- Miguel A Gama Sosa
- General Medical Research Service, James J. Peters Department of Veterans Affairs Medical Center, 130 West Kingsbridge Road, Bronx, New York, 10468, USA.
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
| | - Rita De Gasperi
- Research and Development Service, James J. Peters Department of Veterans Affairs Medical Center, Bronx, New York, USA
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Georgina S Perez Garcia
- Research and Development Service, James J. Peters Department of Veterans Affairs Medical Center, Bronx, New York, USA
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Heidi Sosa
- Research and Development Service, James J. Peters Department of Veterans Affairs Medical Center, Bronx, New York, USA
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Courtney Searcy
- Research and Development Service, James J. Peters Department of Veterans Affairs Medical Center, Bronx, New York, USA
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Danielle Vargas
- Research and Development Service, James J. Peters Department of Veterans Affairs Medical Center, Bronx, New York, USA
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Pierce L Janssen
- Research and Development Service, James J. Peters Department of Veterans Affairs Medical Center, Bronx, New York, USA
- Fishberg Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Gissel M Perez
- Research and Development Service, James J. Peters Department of Veterans Affairs Medical Center, Bronx, New York, USA
| | - Anna E Tschiffely
- Operational and Undersea Medicine Directorate, Naval Medical Research Center, Silver Spring, MD, USA
| | - William G Janssen
- Fishberg Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Richard M McCarron
- Operational and Undersea Medicine Directorate, Naval Medical Research Center, Silver Spring, MD, USA
- Department of Surgery, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
| | - Patrick R Hof
- Fishberg Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Geriatrics and Palliative Care, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Fatemeh G Haghighi
- Research and Development Service, James J. Peters Department of Veterans Affairs Medical Center, Bronx, New York, USA
- Fishberg Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Stephen T Ahlers
- Operational and Undersea Medicine Directorate, Naval Medical Research Center, Silver Spring, MD, USA
| | - Gregory A Elder
- Neurology Service, James J. Peters Department of Veterans Affairs Medical Center, Bronx, New York, USA
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
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177
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Tvrdik P, Kalani MYS. In Vivo Imaging of Microglial Calcium Signaling in Brain Inflammation and Injury. Int J Mol Sci 2017; 18:ijms18112366. [PMID: 29117112 PMCID: PMC5713335 DOI: 10.3390/ijms18112366] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2017] [Revised: 11/01/2017] [Accepted: 11/04/2017] [Indexed: 12/20/2022] Open
Abstract
Microglia, the innate immune sentinels of the central nervous system, are the most dynamic cells in the brain parenchyma. They are the first responders to insult and mediate neuroinflammation. Following cellular damage, microglia extend their processes towards the lesion, modify their morphology, release cytokines and other mediators, and eventually migrate towards the damaged area and remove cellular debris by phagocytosis. Intracellular Ca2+ signaling plays important roles in many of these functions. However, Ca2+ in microglia has not been systematically studied in vivo. Here we review recent findings using genetically encoded Ca2+ indicators and two-photon imaging, which have enabled new insights into Ca2+ dynamics and signaling pathways in large populations of microglia in vivo. These new approaches will help to evaluate pre-clinical interventions and immunomodulation for pathological brain conditions such as stroke and neurodegenerative diseases.
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Affiliation(s)
- Petr Tvrdik
- Department of Neurosurgery, University of Utah School of Medicine, Salt Lake City, UT 84132, USA.
| | - M Yashar S Kalani
- Department of Neurosurgery, University of Virginia School of Medicine, Charlottesville, VA 22908, USA.
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178
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García-Cabezas MÁ, Joyce MKP, John YJ, Zikopoulos B, Barbas H. Mirror trends of plasticity and stability indicators in primate prefrontal cortex. Eur J Neurosci 2017; 46:2392-2405. [PMID: 28921934 DOI: 10.1111/ejn.13706] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Revised: 08/22/2017] [Accepted: 08/24/2017] [Indexed: 12/21/2022]
Abstract
Research on plasticity markers in the cerebral cortex has largely focused on their timing of expression and role in shaping circuits during critical and normal periods. By contrast, little attention has been focused on the spatial dimension of plasticity-stability across cortical areas. The rationale for this analysis is based on the systematic variation in cortical structure that parallels functional specialization and raises the possibility of varying levels of plasticity. Here, we investigated in adult rhesus monkeys the expression of markers related to synaptic plasticity or stability in prefrontal limbic and eulaminate areas that vary in laminar structure. Our findings revealed that limbic areas are impoverished in three markers of stability: intracortical myelin, the lectin Wisteria floribunda agglutinin, which labels perineuronal nets, and parvalbumin, which is expressed in a class of strong inhibitory neurons. By contrast, prefrontal limbic areas were enriched in the enzyme calcium/calmodulin-dependent protein kinase II (CaMKII), known to enhance plasticity. Eulaminate areas have more elaborate laminar architecture than limbic areas and showed the opposite trend: they were enriched in markers of stability and had lower expression of the plasticity-related marker CaMKII. The expression of glial fibrillary acidic protein (GFAP), a marker of activated astrocytes, was also higher in limbic areas, suggesting that cellular stress correlates with the rate of circuit reshaping. Elevated markers of plasticity may endow limbic areas with flexibility necessary for learning and memory within an affective context, but may also render them vulnerable to abnormal structural changes, as seen in neurologic and psychiatric diseases.
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Affiliation(s)
- Miguel Á García-Cabezas
- Neural Systems Laboratory, Department of Health Sciences, Boston University, 635 Commonwealth Ave, Boston, MA, 02215, USA
| | - Mary Kate P Joyce
- Neural Systems Laboratory, Department of Health Sciences, Boston University, 635 Commonwealth Ave, Boston, MA, 02215, USA
| | - Yohan J John
- Neural Systems Laboratory, Department of Health Sciences, Boston University, 635 Commonwealth Ave, Boston, MA, 02215, USA
| | - Basilis Zikopoulos
- Human Systems Neuroscience Laboratory, Boston University, Boston, MA, USA
| | - Helen Barbas
- Neural Systems Laboratory, Department of Health Sciences, Boston University, 635 Commonwealth Ave, Boston, MA, 02215, USA
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179
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Sridar S, Churchward MA, Mushahwar VK, Todd KG, Elias AL. Peptide modification of polyimide-insulated microwires: Towards improved biocompatibility through reduced glial scarring. Acta Biomater 2017; 60:154-166. [PMID: 28735029 DOI: 10.1016/j.actbio.2017.07.026] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Revised: 07/01/2017] [Accepted: 07/18/2017] [Indexed: 01/12/2023]
Abstract
The goal of this study is to improve the integration of implanted microdevices with tissue in the central nervous system (CNS). The long-term utility of neuroprosthetic devices implanted in the CNS is affected by the formation of a scar by resident glial cells (astrocytes and microglia), limiting the viability and functional stability of the devices. Reduction in the proliferation of glial cells is expected to enhance the biocompatibility of devices. We demonstrate the modification of polyimide-insulated microelectrodes with a bioactive peptide KHIFSDDSSE. Microelectrode wires were functionalized with (3-aminopropyl) triethoxy silane (APTES); the peptide was then covalently bonded to the APTES. The soluble peptide was tested in 2D mixed cultures of astrocytes and microglia, and reduced the proliferation of both cell types. The interactions of glial cells with the peptide-modified wires was then examined in 3D cell-laden hydrogels by immunofluorescence microscopy. As expected for uncoated wires, the microglia were first attracted to the wire (7days) followed by astrocyte recruitment and hypertrophy (14days). For the peptide-treated wires, astrocytes coated the wires directly (24h), and formed a thin, stable coating without evidence of hypertrophy, and the attraction of microglia to the wire was significantly reduced. The results suggest a mechanism to improve tissue integration by promoting uniform coating of astrocytes on a foreign body while lessening the reactive response of microglia. We conclude that the bioactive peptide KHIFSDDSSE may be effective in improving the biocompatibility of neural interfaces by both reducing acute glial reactivity and generating stable integration with tissue. STATEMENT OF SIGNIFICANCE The peptide KHIFSDDSSE has previously been shown in vitro to both reduce the proliferation of astrocytes, and to increase the adhesion of astrocyte to glass substrates. Here, we demonstrate a method to apply uniform coatings of peptides to microwires, which could readily be generalized to other peptides and surfaces. We then show that when peptide-modified wires are inserted into 3D cell-laden hydrogels, the normal cellular reaction (microglial activation followed by astrocyte recruitment and hypertrophy) does not occur, rather astrocytes are attracted directly to the surface of the wire, forming a relatively thin and uniform coating. This suggests a method to improve tissue integration of implanted devices to reduce glial scarring and ultimately reduce failure of neural interfaces.
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Affiliation(s)
- Sangita Sridar
- Chemical and Materials Engineering, University of Alberta, Edmonton, AB T6G 1H9, Canada; Alberta Innovates-Health Solutions Interdisciplinary Team in Smart Neural Prostheses (Project SMART), University of Alberta, AB, Canada
| | - Matthew A Churchward
- Neurochemical Research Unit, Department of Psychiatry, University of Alberta, Edmonton, AB T6G 2G3, Canada; Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB T6G 2E1, Canada; Alberta Innovates-Health Solutions Interdisciplinary Team in Smart Neural Prostheses (Project SMART), University of Alberta, AB, Canada
| | - Vivian K Mushahwar
- Division of Physical Medicine and Rehabilitation, University of Alberta, Edmonton, AB T6G 2E1, Canada; Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB T6G 2E1, Canada; Alberta Innovates-Health Solutions Interdisciplinary Team in Smart Neural Prostheses (Project SMART), University of Alberta, AB, Canada
| | - Kathryn G Todd
- Neurochemical Research Unit, Department of Psychiatry, University of Alberta, Edmonton, AB T6G 2G3, Canada; Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB T6G 2E1, Canada; Alberta Innovates-Health Solutions Interdisciplinary Team in Smart Neural Prostheses (Project SMART), University of Alberta, AB, Canada
| | - Anastasia L Elias
- Chemical and Materials Engineering, University of Alberta, Edmonton, AB T6G 1H9, Canada; Alberta Innovates-Health Solutions Interdisciplinary Team in Smart Neural Prostheses (Project SMART), University of Alberta, AB, Canada.
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180
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Caldeira C, Cunha C, Vaz AR, Falcão AS, Barateiro A, Seixas E, Fernandes A, Brites D. Key Aging-Associated Alterations in Primary Microglia Response to Beta-Amyloid Stimulation. Front Aging Neurosci 2017; 9:277. [PMID: 28912710 PMCID: PMC5583148 DOI: 10.3389/fnagi.2017.00277] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Accepted: 08/03/2017] [Indexed: 12/14/2022] Open
Abstract
Alzheimer's disease (AD) is characterized by a progressive cognitive decline and believed to be driven by the self-aggregation of amyloid-β (Aβ) peptide into oligomers and fibrils that accumulate as senile plaques. It is widely accepted that microglia-mediated inflammation is a significant contributor to disease pathogenesis; however, different microglia phenotypes were identified along AD progression and excessive Aβ production was shown to dysregulate cell function. As so, the contribution of microglia to AD pathogenesis remains to be elucidated. In this study, we wondered if isolated microglia cultured for 16 days in vitro (DIV) would react differentially from the 2 DIV cells upon treatment with 1000 nM Aβ1-42 for 24 h. No changes in cell viability were observed and morphometric alterations associated to microglia activation, such as volume increase and process shortening, were obvious in 2 DIV microglia, but less evident in 16 DIV cells. These cells showed lower phagocytic, migration and autophagic properties after Aβ treatment than the 2 DIV cultured microglia. Reduced phagocytosis may derive from increased CD33 expression, reduced triggering receptor expressed on myeloid cells 2 (TREM2) and milk fat globule-EGF factor 8 protein (MFG-E8) levels, which were mainly observed in 16 DIV cells. Activation of inflammatory mediators, such as high mobility group box 1 (HMGB1) and pro-inflammatory cytokines, as well as increased expression of Toll-like receptor 2 (TLR2), TLR4 and fractalkine/CX3C chemokine receptor 1 (CX3CR1) cell surface receptors were prominent in 2 DIV microglia, while elevation of matrix metalloproteinase 9 (MMP9) was marked in 16 DIV cells. Increased senescence-associated β-galactosidase (SA-β-gal) and upregulated miR-146a expression that were observed in 16 DIV cells showed to increase by Aβ in 2 DIV microglia. Additionally, Aβ downregulated miR-155 and miR-124, and reduced the CD11b+ subpopulation in 2 DIV microglia, while increased the number of CD86+ cells in 16 DIV microglia. Simultaneous M1 and M2 markers were found after Aβ treatment, but at lower expression in the in vitro aged microglia. Data show key-aging associated responses by microglia when incubated with Aβ, with a loss of reactivity from the 2 DIV to the 16 DIV cells, which course with a reduced phagocytosis, migration and lower expression of inflammatory miRNAs. These findings help to improve our understanding on the heterogeneous responses that microglia can have along the progression of AD disease and imply that therapeutic approaches may differ from early to late stages.
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Affiliation(s)
- Cláudia Caldeira
- Neuron Glia Biology in Health and Disease, Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de LisboaLisbon, Portugal
| | - Carolina Cunha
- Neuron Glia Biology in Health and Disease, Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de LisboaLisbon, Portugal
| | - Ana R Vaz
- Neuron Glia Biology in Health and Disease, Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de LisboaLisbon, Portugal.,Department of Biochemistry and Human Biology, Faculty of Pharmacy, Universidade de LisboaLisbon, Portugal
| | - Ana S Falcão
- Department of Biochemistry and Human Biology, Faculty of Pharmacy, Universidade de LisboaLisbon, Portugal
| | - Andreia Barateiro
- Neuron Glia Biology in Health and Disease, Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de LisboaLisbon, Portugal
| | - Elsa Seixas
- Obesity Laboratory, Instituto Gulbenkian de CiênciaOeiras, Portugal
| | - Adelaide Fernandes
- Neuron Glia Biology in Health and Disease, Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de LisboaLisbon, Portugal.,Department of Biochemistry and Human Biology, Faculty of Pharmacy, Universidade de LisboaLisbon, Portugal
| | - Dora Brites
- Neuron Glia Biology in Health and Disease, Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de LisboaLisbon, Portugal.,Department of Biochemistry and Human Biology, Faculty of Pharmacy, Universidade de LisboaLisbon, Portugal
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181
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Kolos EA, Korzhevskii DE. Activation of Microglyocytes in the Anterior Horns of Rat Spinal Cord after Administration of Bacterial Lipopolysaccharide. Bull Exp Biol Med 2017; 163:515-518. [PMID: 28853070 DOI: 10.1007/s10517-017-3841-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Indexed: 10/19/2022]
Abstract
We studied the reaction of the microglia of the anterior horns of the rat spinal cord to intraperitoneal administration of bacterial LPS. Immunohistochemical analysis showed that acute systemic inflammation leads to activation of more than half of microglial cells as soon as in 24 h after LPS injection, while the total number of microglial cells does not change significantly. It was hypothesized that activated microglial cells are involved in the reorganization of synaptic connections, but do not have a neurotoxic effect.
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Affiliation(s)
- E A Kolos
- Institute of Experimental Medicine, St. Petersburg, Russia.
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182
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Fernández-Arjona MDM, Grondona JM, Granados-Durán P, Fernández-Llebrez P, López-Ávalos MD. Microglia Morphological Categorization in a Rat Model of Neuroinflammation by Hierarchical Cluster and Principal Components Analysis. Front Cell Neurosci 2017; 11:235. [PMID: 28848398 PMCID: PMC5550745 DOI: 10.3389/fncel.2017.00235] [Citation(s) in RCA: 236] [Impact Index Per Article: 33.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Accepted: 07/25/2017] [Indexed: 12/24/2022] Open
Abstract
It is known that microglia morphology and function are closely related, but only few studies have objectively described different morphological subtypes. To address this issue, morphological parameters of microglial cells were analyzed in a rat model of aseptic neuroinflammation. After the injection of a single dose of the enzyme neuraminidase (NA) within the lateral ventricle (LV) an acute inflammatory process occurs. Sections from NA-injected animals and sham controls were immunolabeled with the microglial marker IBA1, which highlights ramifications and features of the cell shape. Using images obtained by section scanning, individual microglial cells were sampled from various regions (septofimbrial nucleus, hippocampus and hypothalamus) at different times post-injection (2, 4 and 12 h). Each cell yielded a set of 15 morphological parameters by means of image analysis software. Five initial parameters (including fractal measures) were statistically different in cells from NA-injected rats (most of them IL-1β positive, i.e., M1-state) compared to those from control animals (none of them IL-1β positive, i.e., surveillant state). However, additional multimodal parameters were revealed more suitable for hierarchical cluster analysis (HCA). This method pointed out the classification of microglia population in four clusters. Furthermore, a linear discriminant analysis (LDA) suggested three specific parameters to objectively classify any microglia by a decision tree. In addition, a principal components analysis (PCA) revealed two extra valuable variables that allowed to further classifying microglia in a total of eight sub-clusters or types. The spatio-temporal distribution of these different morphotypes in our rat inflammation model allowed to relate specific morphotypes with microglial activation status and brain location. An objective method for microglia classification based on morphological parameters is proposed. Main pointsMicroglia undergo a quantifiable morphological change upon neuraminidase induced inflammation. Hierarchical cluster and principal components analysis allow morphological classification of microglia. Brain location of microglia is a relevant factor.
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Affiliation(s)
- María Del Mar Fernández-Arjona
- Departamento de Biología Celular, Facultad de Ciencias, Genética y Fisiología, Instituto de Investigación Biomédica de Málaga (IBIMA), Universidad de MálagaMálaga, Spain
| | - Jesús M Grondona
- Departamento de Biología Celular, Facultad de Ciencias, Genética y Fisiología, Instituto de Investigación Biomédica de Málaga (IBIMA), Universidad de MálagaMálaga, Spain
| | - Pablo Granados-Durán
- Departamento de Biología Celular, Facultad de Ciencias, Genética y Fisiología, Instituto de Investigación Biomédica de Málaga (IBIMA), Universidad de MálagaMálaga, Spain
| | - Pedro Fernández-Llebrez
- Departamento de Biología Celular, Facultad de Ciencias, Genética y Fisiología, Instituto de Investigación Biomédica de Málaga (IBIMA), Universidad de MálagaMálaga, Spain
| | - María D López-Ávalos
- Departamento de Biología Celular, Facultad de Ciencias, Genética y Fisiología, Instituto de Investigación Biomédica de Málaga (IBIMA), Universidad de MálagaMálaga, Spain
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183
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Allelic difference in Mhc2ta confers altered microglial activation and susceptibility to α-synuclein-induced dopaminergic neurodegeneration. Neurobiol Dis 2017; 106:279-290. [PMID: 28736195 DOI: 10.1016/j.nbd.2017.07.016] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 06/20/2017] [Accepted: 07/19/2017] [Indexed: 11/22/2022] Open
Abstract
Parkinson's Disease (PD) is a complex and heterogeneous neurodegenerative disease characterized by a progressive loss of dopaminergic neurons in the substantia nigra pars compacta and pathological intracellular accumulation of alpha-synuclein (α-syn). In the vast majority of PD patients, the disease has a complex etiology, defined by multiple genetic and environmental risk factors. Common genetic variants in the human leukocyte-antigen (HLA) region have been associated to PD risk and the carriage of these can double the risk to develop PD. Among these common genetic variants are the ones that modulate the expression of MHCII genes. MHCII molecules encoded in the HLA-region are responsible for antigen presentation to the adaptive immune system and have a key role in inflammatory processes. In addition to cis‑variants affecting MHCII expression, a transactivator encoded by the Mhc2ta gene is the major regulator of MHCII expression. We have previously identified variations in the promoter region of Mhc2ta, encoded in the VRA4 region, to regulate MHCII expression in rats. The expression of MHCII is known to be required in the response to α-syn. However, how the expression of MHCII affects the activation of microglial or the impact of physiological, differential Mhc2ta expression on degeneration of dopaminergic neurons has not previously been addressed. Here we addressed the implications of common genetic allelic variants of the major regulator of MHCII expression on α-syn-induced microglia activation and the severity of the dopaminergic neurodegeneration. We used a viral vector technology to overexpress α-syn in two rat strains; Dark agouti (DA) wild type and DA.VRA4-congenic rats. The congenic strain carries PVG alleles in the VRA4 locus and therefore displays lower Mhc2ta expression levels compared to DA rats. We analyzed the impact of this physiological differential Mhc2ta expression on gliosis, inflammation, degeneration of the nigro-striatal dopamine system and behavioral deficits after α-syn overexpression. We report that allelic variants of Mhc2ta differently modified the microglial activation in response to overexpression of human α-syn in rats. Overexpression of α-syn led to a larger denervation of the nigro-striatal system and significant behavioral deficits in DA.VRA4 congenic rats with lower Mhc2ta expression compared to DA rats. These results indicate that Mhc2ta is a key upstream regulator of the inflammatory response in PD pathology.
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184
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Obst J, Simon E, Mancuso R, Gomez-Nicola D. The Role of Microglia in Prion Diseases: A Paradigm of Functional Diversity. Front Aging Neurosci 2017; 9:207. [PMID: 28690540 PMCID: PMC5481309 DOI: 10.3389/fnagi.2017.00207] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Accepted: 06/09/2017] [Indexed: 12/26/2022] Open
Abstract
Inflammation is a major component of neurodegenerative diseases. Microglia are the innate immune cells in the central nervous system (CNS). In the healthy brain, microglia contribute to tissue homeostasis and regulation of synaptic plasticity. Under disease conditions, they play a key role in the development and maintenance of the neuroinflammatory response, by showing enhanced proliferation and activation. Prion diseases are progressive chronic neurodegenerative disorders associated with the accumulation of the scrapie prion protein PrPSc, a misfolded conformer of the cellular prion protein PrPC. This review article provides the current knowledge on the role of microglia in the pathogenesis of prion disease. A large body of evidence shows that microglia can trigger neurotoxic pathways contributing to progressive degeneration. Yet, microglia are also crucial for controlling inflammatory, repair and regenerative processes. This dual role of microglia is regulated by multiple pathways and evidences the ability of these cells to polarize into distinct phenotypes with characteristic functions. The awareness that the neuroinflammatory response is inextricably involved in producing tissue damage as well as repair in neurodegenerative disorders, opens new perspectives for the modulation of the immune system. A better understanding of this complex process will be essential for developing effective therapies for neurodegenerative diseases, in order to improve the quality of life of patients and mitigating the personal, economic and social consequences derived from these diseases.
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Affiliation(s)
- Juliane Obst
- Biological Sciences, University of Southampton, Southampton General HospitalSouthampton, United Kingdom
| | - Emilie Simon
- Biological Sciences, University of Southampton, Southampton General HospitalSouthampton, United Kingdom
| | - Renzo Mancuso
- Biological Sciences, University of Southampton, Southampton General HospitalSouthampton, United Kingdom
| | - Diego Gomez-Nicola
- Biological Sciences, University of Southampton, Southampton General HospitalSouthampton, United Kingdom
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185
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Wang C, Yeo S, Haas MA, Guan JL. Autophagy gene FIP200 in neural progenitors non-cell autonomously controls differentiation by regulating microglia. J Cell Biol 2017. [PMID: 28634261 PMCID: PMC5551701 DOI: 10.1083/jcb.201609093] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Recent studies have shown important roles for autophagy genes in the regulation of different tissue stem cells, including neural stem/progenitor cells (NSCs). However, little is known about whether autophagy can regulate NSCs through cell-extrinsic mechanisms. Here, we show that deletion of an essential autophagy gene, FIP200, in NSCs increased expression of Ccl5 and Cxcl10 in a p53-independent manner, mediating increased infiltration of microglia into the subventricular zone of both FIP200hGFAP conditional knockout (cKO) and FIP200;p53hGFAP 2cKO mice. The microglia exhibited an activated M1 phenotype consistent with their potential to inhibit differentiation of FIP200-null NSCs. Blocking either microglia infiltration or activation rescued the deficient differentiation of FIP200-null NSCs from FIP200;p53hGFAP 2cKO mice. Lastly, we showed that increased chemokine expression in FIP200-null NSCs was induced by abnormal p62 aggregate formation and activation of NF-κB signaling. Our results suggest that autophagy plays a crucial role in regulating neurogenesis and restricting local immune response in postnatal NSCs through non-cell autonomous mechanisms.
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Affiliation(s)
- Chenran Wang
- Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, OH
| | - Syn Yeo
- Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, OH
| | - Michael A Haas
- Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, OH
| | - Jun-Lin Guan
- Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, OH
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186
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Kabba JA, Xu Y, Christian H, Ruan W, Chenai K, Xiang Y, Zhang L, Saavedra JM, Pang T. Microglia: Housekeeper of the Central Nervous System. Cell Mol Neurobiol 2017; 38:53-71. [PMID: 28534246 DOI: 10.1007/s10571-017-0504-2] [Citation(s) in RCA: 152] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 05/16/2017] [Indexed: 12/17/2022]
Abstract
Microglia, of myeloid origin, play fundamental roles in the control of immune responses and the maintenance of central nervous system homeostasis. These cells, just like peripheral macrophages, may be activated into M1 pro-inflammatory or M2 anti-inflammatory phenotypes by appropriate stimuli. Microglia do not respond in isolation, but form part of complex networks of cells influencing each other. This review addresses the complex interaction of microglia with each cell type in the brain: neurons, astrocytes, cerebrovascular endothelial cells, and oligodendrocytes. We also highlight the participation of microglia in the maintenance of homeostasis in the brain, and their roles in the development and progression of age-related neurodegenerative disorders.
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Affiliation(s)
- John Alimamy Kabba
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Drug Screening, Jiangsu Key Laboratory of Drug Discovery for Metabolic Diseases, Jiangsu Key Laboratory of Druggability of Biopharmaceuticals, China Pharmaceutical University, #24 Tong Jia Xiang Street, Nanjing, 210009, People's Republic of China
| | - Yazhou Xu
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Drug Screening, Jiangsu Key Laboratory of Drug Discovery for Metabolic Diseases, Jiangsu Key Laboratory of Druggability of Biopharmaceuticals, China Pharmaceutical University, #24 Tong Jia Xiang Street, Nanjing, 210009, People's Republic of China
| | - Handson Christian
- Department of Pharmacology, School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, People's Republic of China
| | - Wenchen Ruan
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Drug Screening, Jiangsu Key Laboratory of Drug Discovery for Metabolic Diseases, Jiangsu Key Laboratory of Druggability of Biopharmaceuticals, China Pharmaceutical University, #24 Tong Jia Xiang Street, Nanjing, 210009, People's Republic of China
| | - Kitchen Chenai
- School of Pharmacy, China Pharmaceutical University, Nanjing, 210009, People's Republic of China
| | - Yun Xiang
- Department of Laboratory Medicine, Wuhan Children's Hospital, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, 430016, People's Republic of China
| | - Luyong Zhang
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Drug Screening, Jiangsu Key Laboratory of Drug Discovery for Metabolic Diseases, Jiangsu Key Laboratory of Druggability of Biopharmaceuticals, China Pharmaceutical University, #24 Tong Jia Xiang Street, Nanjing, 210009, People's Republic of China
| | - Juan M Saavedra
- Department of Pharmacology and Physiology, Georgetown University Medical Center, Washington DC, 20057, USA
| | - Tao Pang
- State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Drug Screening, Jiangsu Key Laboratory of Drug Discovery for Metabolic Diseases, Jiangsu Key Laboratory of Druggability of Biopharmaceuticals, China Pharmaceutical University, #24 Tong Jia Xiang Street, Nanjing, 210009, People's Republic of China. .,Department of Pharmacology and Physiology, Georgetown University Medical Center, Washington DC, 20057, USA.
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187
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Franco Bocanegra DK, Nicoll JAR, Boche D. Innate immunity in Alzheimer's disease: the relevance of animal models? J Neural Transm (Vienna) 2017; 125:827-846. [PMID: 28516241 PMCID: PMC5911273 DOI: 10.1007/s00702-017-1729-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 04/27/2017] [Indexed: 12/12/2022]
Abstract
The mouse is one of the organisms most widely used as an animal model in biomedical research, due to the particular ease with which it can be handled and reproduced in laboratory. As a member of the mammalian class, mice share with humans many features regarding metabolic pathways, cell morphology and anatomy. However, important biological differences between mice and humans exist and must be taken into consideration when interpreting research results, to properly translate evidence from experimental studies into information that can be useful for human disease prevention and/or treatment. With respect to Alzheimer’s disease (AD), much of the experimental information currently known about this disease has been gathered from studies using mainly mice as models. Therefore, it is notably important to fully characterise the differences between mice and humans regarding important aspects of the disease. It is now widely known that inflammation plays an important role in the development of AD, a role that is not only a response to the surrounding pathological environment, but rather seems to be strongly implicated in the aetiology of the disease as indicated by the genetic studies. This review highlights relevant differences in inflammation and in microglia, the innate immune cell of the brain, between mice and humans regarding genetics and morphology in normal ageing, and the relationship of microglia with AD-like pathology, the inflammatory profile, and cognition. We conclude that some noteworthy differences exist between mice and humans regarding microglial characteristics, in distribution, gene expression, and states of activation. This may have repercussions in the way that transgenic mice respond to, and influence, the AD-like pathology. However, despite these differences, human and mouse microglia also show similarities in morphology and behaviour, such that the mouse is a suitable model for studying the role of microglia, as long as these differences are taken into consideration when delineating new strategies to approach the study of neurodegenerative diseases.
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Affiliation(s)
- Diana K Franco Bocanegra
- Clinical Neurosciences, Clinical and Experimental Sciences Academic Unit, Faculty of Medicine, University of Southampton, Southampton General Hospital, Mailpoint 806, Southampton, SO16 6YD, UK
| | - James A R Nicoll
- Clinical Neurosciences, Clinical and Experimental Sciences Academic Unit, Faculty of Medicine, University of Southampton, Southampton General Hospital, Mailpoint 806, Southampton, SO16 6YD, UK.,Department of Cellular Pathology, University Hospital Southampton NHS Foundation Trust, Southampton, Southampton, SO16 6YD, UK
| | - Delphine Boche
- Clinical Neurosciences, Clinical and Experimental Sciences Academic Unit, Faculty of Medicine, University of Southampton, Southampton General Hospital, Mailpoint 806, Southampton, SO16 6YD, UK.
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188
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Lee AS, Azmitia EC, Whitaker-Azmitia PM. Developmental microglial priming in postmortem autism spectrum disorder temporal cortex. Brain Behav Immun 2017; 62:193-202. [PMID: 28159644 DOI: 10.1016/j.bbi.2017.01.019] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Revised: 01/13/2017] [Accepted: 01/26/2017] [Indexed: 10/20/2022] Open
Abstract
Microglia can shift into different complex morphologies depending on the microenvironment of the central nervous system (CNS). The distinct morphologies correlate with specific functions and can indicate the pathophysiological state of the CNS. Previous postmortem studies of autism spectrum disorder (ASD) showed neuroinflammation in ASD indicated by increased microglial density. These changes in the microglia density can be accompanied by changes in microglia phenotype but the individual contribution of different microglia phenotypes to the pathophysiology of ASD remains unclear. Here, we used an unbiased stereological approach to quantify six structurally and functionally distinct microglia phenotypes in postmortem human temporal cortex, which were immuno-stained with Iba1. The total density of all microglia phenotypes did not differ between ASD donors and typically developing individual donors. However, there was a significant decrease in ramified microglia in both gray matter and white matter of ASD, and a significant increase in primed microglia in gray matter of ASD compared to typically developing individuals. This increase in primed microglia showed a positive correlation with donor age in both gray matter and white of ASD, but not in typically developing individuals. Our results provide evidence of a shift in microglial phenotype that may indicate impaired synaptic plasticity and a chronic vulnerability to exaggerated immune responses.
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Affiliation(s)
- Andrew S Lee
- Department of Psychology, Stony Brook University, Stony Brook, NY 11794, USA; Department of Biology, New York University, New York, NY 10003, USA; Max Planck Institute for Biological Cybernetics, 72076 Tuebingen, Germany.
| | - Efrain C Azmitia
- Department of Biology, New York University, New York, NY 10003, USA
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189
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Distinct Pattern of Microgliosis in the Olfactory Bulb of Neurodegenerative Proteinopathies. Neural Plast 2017; 2017:3851262. [PMID: 28409032 PMCID: PMC5376461 DOI: 10.1155/2017/3851262] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 11/24/2016] [Accepted: 12/28/2016] [Indexed: 12/25/2022] Open
Abstract
The olfactory bulb (OB) shows early neuropathological hallmarks in numerous neurodegenerative diseases, for example, in Alzheimer's disease (AD) and Parkinson's disease (PD). The glomerular and granular cell layer of the OB is characterized by preserved cellular plasticity in the adult brain. In turn, alterations of this cellular plasticity are related to neuroinflammation such as microglia activation, implicated in the pathogenesis of AD and PD, as well as frontotemporal lobe degeneration (FTLD). To determine microglia proliferation and activation we analyzed ionized calcium binding adaptor molecule 1 (Iba1) expressing microglia in the glomerular and granular cell layer, and the olfactory tract of the OB from patients with AD, PD dementia/dementia with Lewy bodies (PDD/DLB), and FTLD compared to age-matched controls. The number of Iba1 and CD68 positive microglia associated with enlarged amoeboid microglia was increased particularly in AD, to a lesser extent in FTLD and PDD/DLB as well, while the proportion of proliferating microglia was not altered. In addition, cells expressing the immature neuronal marker polysialylated neural cell adhesion molecule (PSA-NCAM) were increased in the glomerular layer of PDD/DLB and FTLD cases only. These findings provide novel and detailed insights into differential levels of microglia activation in the OB of neurodegenerative diseases.
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190
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Chronic methamphetamine exposure significantly decreases microglia activation in the arcuate nucleus. J Chem Neuroanat 2017; 82:5-11. [PMID: 28323108 DOI: 10.1016/j.jchemneu.2017.03.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 12/04/2016] [Accepted: 03/14/2017] [Indexed: 12/30/2022]
Abstract
Methamphetamine is a powerful psychostimulant drug and its use and abuse necessitates a better understanding of its neurobiobehavioral effects. The acute effects of binge dosing of methamphetamine on the neurons in the CNS are well studied. However, the long-term effects of chronic, low-dose methamphetamine are less well characterized, especially in other cell types and areas outside of the major dopamine pathways. Mice were administered 5mg/kg/day methamphetamine for ten days and brain tissue was analyzed using histochemistry and image analysis. Increased microglia activity in the striatum confirmed toxic effects of methamphetamine in this brain region using this dosing paradigm. A significant decrease in microglia activity in the arcuate nucleus of the hypothalamus was observed with no effect noted on dopamine neurons in the arcuate nucleus. Given the importance of this area in homeostatic and neuroendocrine regulation, the current study highlights the need to more fully understand the systemic effects of chronic, low-dose methamphetamine use. The novel finding of microglia downregulation after chronic methamphetamine could lead to advances in understanding neuroinflammatory responses towards addiction treatment and protection from psychostimulant-induced neurotoxicity.
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191
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Jure I, Pietranera L, De Nicola AF, Labombarda F. Spinal Cord Injury Impairs Neurogenesis and Induces Glial Reactivity in the Hippocampus. Neurochem Res 2017; 42:2178-2190. [DOI: 10.1007/s11064-017-2225-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 03/02/2017] [Accepted: 03/06/2017] [Indexed: 11/29/2022]
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192
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Kure C, Timmer J, Stough C. The Immunomodulatory Effects of Plant Extracts and Plant Secondary Metabolites on Chronic Neuroinflammation and Cognitive Aging: A Mechanistic and Empirical Review. Front Pharmacol 2017; 8:117. [PMID: 28344556 PMCID: PMC5344987 DOI: 10.3389/fphar.2017.00117] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Accepted: 02/24/2017] [Indexed: 01/25/2023] Open
Abstract
Advances in healthcare have considerably improved the life expectancy of the human population over the last century and this has brought about new challenges. As we live longer the capacity for cognitive aging increases. Consequently, it has been noted that decline in cognitive performance in the elderly in domains of reasoning, problem solving skills, attention, processing speed, working memory and episodic memory is a significant societal problem. Despite the enormity of this issue there are relatively few interventions for cognitive aging. This may be due to our current state of knowledge on biological factors that underpin cognitive aging. One of the biological contributors to cognitive aging is chronic neuroinflammation. This review will provide an overview of the peripheral and central mechanisms involved in chronic neuroinflammation and how neuroinflammation may be related to age-associated cognitive decline. Plant based extracts including herbal and nutritional supplements with anti-inflammatory properties will be examined in relation to their utility in treating age-related cognitive decline. Plant based extracts in particular offer interesting pharmacological properties that may be quickly utilized to prevent cognitive aging.
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Affiliation(s)
| | | | - Con Stough
- Swinburne Centre for Human Psychopharmacology, Swinburne UniversityHawthorn, VIC, Australia
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193
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Wang ZJ, Martin JA, Gancarz AM, Adank DN, Sim FJ, Dietz DM. Activin A is increased in the nucleus accumbens following a cocaine binge. Sci Rep 2017; 7:43658. [PMID: 28272550 PMCID: PMC5341561 DOI: 10.1038/srep43658] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 01/26/2017] [Indexed: 11/24/2022] Open
Abstract
Drug addiction is a long-lasting disease characterized by compulsive drug intake mediated in part by neuronal and biological adaptations in key brain areas, such as the nucleus accumbens (NAc). While we previously demonstrated involvement of the activin 2a receptor in drug taking, the role of its ligand, activin A, in cocaine relapse is unknown. Activin A levels in the NAc were assessed via ELISA and immunohistochemistry (in neurons, astrocytes, and microglia) following a cocaine binge paradigm. Cocaine exposure significantly increased the levels of activin A in the NAc of animals that had self-administered cocaine prior to the 14-day withdrawal compared with levels in saline controls. This was accompanied by an increase in the proportion of IBA1+ microglia in the NAc that were immunopositive for activin A. In contrast, the proportions of NeuN+ neurons and GFAP+ astrocytes that were immunopositive for activin A remained unaltered. In conclusion, these data suggest that increased secretion of activin A, particularly from microglia, in the NAc represents a novel potential target for the treatment of cocaine relapse.
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Affiliation(s)
- Zi-Jun Wang
- Department of Pharmacology and Toxicology, Research Institute on Addictions, Program in Neuroscience, State University of New York at Buffalo, Buffalo, NY, USA
- Department of Psychology, State University of New York at Buffalo, Buffalo, NY, USA
| | - Jennifer A. Martin
- Department of Pharmacology and Toxicology, Research Institute on Addictions, Program in Neuroscience, State University of New York at Buffalo, Buffalo, NY, USA
- Department of Psychology, State University of New York at Buffalo, Buffalo, NY, USA
| | - Amy M. Gancarz
- Department of Pharmacology and Toxicology, Research Institute on Addictions, Program in Neuroscience, State University of New York at Buffalo, Buffalo, NY, USA
- Department of Psychology, State University of New York at Buffalo, Buffalo, NY, USA
- Department of Psychology, California State University Bakersfield, Bakersfield, CA, USA
| | - Danielle N. Adank
- Department of Pharmacology and Toxicology, Research Institute on Addictions, Program in Neuroscience, State University of New York at Buffalo, Buffalo, NY, USA
| | - Fraser J. Sim
- Department of Pharmacology and Toxicology, Research Institute on Addictions, Program in Neuroscience, State University of New York at Buffalo, Buffalo, NY, USA
| | - David M. Dietz
- Department of Pharmacology and Toxicology, Research Institute on Addictions, Program in Neuroscience, State University of New York at Buffalo, Buffalo, NY, USA
- Department of Psychology, State University of New York at Buffalo, Buffalo, NY, USA
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194
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Tamura T, Aoyama M, Ukai S, Kakita H, Sobue K, Asai K. Neuroprotective erythropoietin attenuates microglial activation, including morphological changes, phagocytosis, and cytokine production. Brain Res 2017; 1662:65-74. [PMID: 28257780 DOI: 10.1016/j.brainres.2017.02.023] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Revised: 01/27/2017] [Accepted: 02/21/2017] [Indexed: 12/12/2022]
Abstract
Erythropoietin (EPO), a hematopoietic hormonal cytokine induced in response to hypoxia, has neuroprotective effects. EPO receptor (EPOR) is expressed in microglia, resident immune cells in the brain. However, the effect of EPO on microglial activation is not clear. In the present study, we demonstrated that the EPOR is highly expressed in microglia, rather than in neurons or astrocytes, in in vitro experiments. Therefore, we investigated whether EPO could attenuate lipopolysaccharide (LPS)-mediated activation of microglia in vitro. The BV-2 microglial cell line was treated with LPS in the absence or presence of EPO. In the presence of EPO, microglial expression of LPS-induced inflammatory cytokine genes was significantly decreased. In addition, EPO suppressed the LPS-induced phagocytic activity of BV-2 cells towards fluorescent beads, as well as induction of inducible nitric oxide synthase. In in vivo experiments, EPO significantly decreased the LPS-induced expression of inflammatory cytokine genes in mouse brains. Furthermore, morphological analysis of cortical microglia in the brains of mice stimulated with LPS revealed that combined treatment with EPO alleviated LPS-induced morphological changes in the microglia. These data indicate that EPO attenuates microglial activation, including morphological changes in vivo, phagocytosis in vitro, and the production of inflammatory cytokines in vivo and in vitro. Further investigation of EPO modulation of LPS-induced microglial activation may contribute to the development of novel neuroprotective therapies.
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Affiliation(s)
- Tetsuya Tamura
- Department of Molecular Neurobiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan; Department of Anesthesiology and Intensive Care Medicine, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.
| | - Mineyoshi Aoyama
- Department of Molecular Neurobiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan; Department of Pathobiology, Nagoya City University Graduate School of Pharmaceutical Sciences, Nagoya, Japan.
| | - Seiko Ukai
- Department of Molecular Neurobiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.
| | - Hiroki Kakita
- Department of Molecular Neurobiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan; Department of Perinatal and Neonatal Medicine, Aichi Medical University, Nagakute, Japan.
| | - Kazuya Sobue
- Department of Anesthesiology and Intensive Care Medicine, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.
| | - Kiyofumi Asai
- Department of Molecular Neurobiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.
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195
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Surowka AD, Pilling M, Henderson A, Boutin H, Christie L, Szczerbowska-Boruchowska M, Gardner P. FTIR imaging of the molecular burden around Aβ deposits in an early-stage 3-Tg-APP-PSP1-TAU mouse model of Alzheimer's disease. Analyst 2017; 142:156-168. [DOI: 10.1039/c6an01797e] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
High spatial resolution FTIR imaging of early-stage 3-Tg-APP-PSP1-TAU mouse brain identifies molecular burden around Aβ deposits.
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Affiliation(s)
- Artur Dawid Surowka
- AGH University of Science and Technology
- Faculty of Physics and Applied Computer Science
- Krakow
- Poland
| | - Michael Pilling
- Manchester Institute of Biotechnology
- University of Manchester
- Manchester
- UK
- School of Chemical Engineering and Analytical Science
| | - Alex Henderson
- Manchester Institute of Biotechnology
- University of Manchester
- Manchester
- UK
- School of Chemical Engineering and Analytical Science
| | - Herve Boutin
- Wolfson Molecular Imaging Centre
- University of Manchester
- Manchester
- UK
| | - Lidan Christie
- Wolfson Molecular Imaging Centre
- University of Manchester
- Manchester
- UK
| | | | - Peter Gardner
- Manchester Institute of Biotechnology
- University of Manchester
- Manchester
- UK
- School of Chemical Engineering and Analytical Science
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196
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Haroon E, Miller AH, Sanacora G. Inflammation, Glutamate, and Glia: A Trio of Trouble in Mood Disorders. Neuropsychopharmacology 2017; 42:193-215. [PMID: 27629368 PMCID: PMC5143501 DOI: 10.1038/npp.2016.199] [Citation(s) in RCA: 317] [Impact Index Per Article: 45.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 09/05/2016] [Accepted: 09/08/2016] [Indexed: 02/07/2023]
Abstract
Increasing data indicate that inflammation and alterations in glutamate neurotransmission are two novel pathways to pathophysiology in mood disorders. The primary goal of this review is to illustrate how these two pathways may converge at the level of the glia to contribute to neuropsychiatric disease. We propose that a combination of failed clearance and exaggerated release of glutamate by glial cells during immune activation leads to glutamate increases and promotes aberrant extrasynaptic signaling through ionotropic and metabotropic glutamate receptors, ultimately resulting in synaptic dysfunction and loss. Furthermore, glutamate diffusion outside the synapse can lead to the loss of synaptic fidelity and specificity of neurotransmission, contributing to circuit dysfunction and behavioral pathology. This review examines the fundamental role of glia in the regulation of glutamate, followed by a description of the impact of inflammation on glial glutamate regulation at the cellular, molecular, and metabolic level. In addition, the role of these effects of inflammation on glia and glutamate in mood disorders will be discussed along with their translational implications.
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Affiliation(s)
- Ebrahim Haroon
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA
| | - Andrew H Miller
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA
| | - Gerard Sanacora
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
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197
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Reemst K, Noctor SC, Lucassen PJ, Hol EM. The Indispensable Roles of Microglia and Astrocytes during Brain Development. Front Hum Neurosci 2016; 10:566. [PMID: 27877121 PMCID: PMC5099170 DOI: 10.3389/fnhum.2016.00566] [Citation(s) in RCA: 336] [Impact Index Per Article: 42.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Accepted: 10/25/2016] [Indexed: 01/17/2023] Open
Abstract
Glia are essential for brain functioning during development and in the adult brain. Here, we discuss the various roles of both microglia and astrocytes, and their interactions during brain development. Although both cells are fundamentally different in origin and function, they often affect the same developmental processes such as neuro-/gliogenesis, angiogenesis, axonal outgrowth, synaptogenesis and synaptic pruning. Due to their important instructive roles in these processes, dysfunction of microglia or astrocytes during brain development could contribute to neurodevelopmental disorders and potentially even late-onset neuropathology. A better understanding of the origin, differentiation process and developmental functions of microglia and astrocytes will help to fully appreciate their role both in the developing as well as in the adult brain, in health and disease.
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Affiliation(s)
- Kitty Reemst
- Swammerdam Institute for Life Sciences, University of AmsterdamAmsterdam, Netherlands
| | - Stephen C. Noctor
- Department of Psychiatry and Behavioral Sciences, UC Davis MIND InstituteSacramento, CA, USA
| | - Paul J. Lucassen
- Swammerdam Institute for Life Sciences, University of AmsterdamAmsterdam, Netherlands
| | - Elly M. Hol
- Swammerdam Institute for Life Sciences, University of AmsterdamAmsterdam, Netherlands
- Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center UtrechtUtrecht, Netherlands
- Netherlands Institute for NeuroscienceAmsterdam, Netherlands
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198
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García-Cabezas MÁ, John YJ, Barbas H, Zikopoulos B. Distinction of Neurons, Glia and Endothelial Cells in the Cerebral Cortex: An Algorithm Based on Cytological Features. Front Neuroanat 2016; 10:107. [PMID: 27847469 PMCID: PMC5088408 DOI: 10.3389/fnana.2016.00107] [Citation(s) in RCA: 137] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 10/20/2016] [Indexed: 11/13/2022] Open
Abstract
The estimation of the number or density of neurons and types of glial cells and their relative proportions in different brain areas are at the core of rigorous quantitative neuroanatomical studies. Unfortunately, the lack of detailed, updated, systematic and well-illustrated descriptions of the cytology of neurons and glial cell types, especially in the primate brain, makes such studies especially demanding, often limiting their scope and broad use. Here, following an extensive analysis of histological materials and the review of current and classical literature, we compile a list of precise morphological criteria that can facilitate and standardize identification of cells in stained sections examined under the microscope. We describe systematically and in detail the cytological features of neurons and glial cell types in the cerebral cortex of the macaque monkey and the human using semithin and thick sections stained for Nissl. We used this classical staining technique because it labels all cells in the brain in distinct ways. In addition, we corroborate key distinguishing characteristics of different cell types in sections immunolabeled for specific markers counterstained for Nissl and in ultrathin sections processed for electron microscopy. Finally, we summarize the core features that distinguish each cell type in easy-to-use tables and sketches, and structure these key features in an algorithm that can be used to systematically distinguish cellular types in the cerebral cortex. Moreover, we report high inter-observer algorithm reliability, which is a crucial test for obtaining consistent and reproducible cell counts in unbiased stereological studies. This protocol establishes a consistent framework that can be used to reliably identify and quantify cells in the cerebral cortex of primates as well as other mammalian species in health and disease.
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Affiliation(s)
| | - Yohan J John
- Neural Systems Laboratory, Department of Health Sciences, Boston University Boston, MA, USA
| | - Helen Barbas
- Neural Systems Laboratory, Department of Health Sciences, Boston University Boston, MA, USA
| | - Basilis Zikopoulos
- Human Systems Neuroscience Laboratory, Department of Health Sciences, Boston University Boston, MA, USA
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199
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Neuropathology of mood disorders: do we see the stigmata of inflammation? Transl Psychiatry 2016; 6:e946. [PMID: 27824355 PMCID: PMC5314124 DOI: 10.1038/tp.2016.212] [Citation(s) in RCA: 118] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Revised: 07/08/2016] [Accepted: 08/30/2016] [Indexed: 12/15/2022] Open
Abstract
A proportion of cases with mood disorders have elevated inflammatory markers in the blood that conceivably may result from stress, infection and/or autoimmunity. However, it is not yet clear whether depression is a neuroinflammatory disease. Multiple histopathological and molecular abnormalities have been found postmortem but the etiology of these abnormalities is unknown. Here, we take an immunological perspective of this literature. Increases in activated microglia or perivascular macrophages in suicide victims have been reported in the parenchyma. In contrast, astrocytic markers generally are downregulated in mood disorders. Impairment of astrocytic function likely compromises the reuptake of glutamate potentially leading to excitotoxicity. Inflammatory cytokines and microglia/macrophage-derived quinolinic acid (QA) downregulate the excitatory amino acid transporters responsible for this reuptake, while QA has the additional effect of inhibiting astroglial glutamine synthetase, which converts glutamate to glutamine. Given that oligodendroglia are particularly vulnerable to inflammation, it is noteworthy that reductions in numbers or density of oligodendrocyte cells are one of the most prominent findings in depression. Structural and/or functional changes to GABAergic interneurons also are salient in postmortem brain samples, and may conceivably be related to early inflammatory insults. Although the postmortem data are consistent with a neuroimmune etiology in a subgroup of depressed individuals, we do not argue that all depression-associated abnormalities are reflective of a neuroinflammatory process or even that all immunological activity in the brain is deleterious. Rather, we highlight the pervasive role of immune signaling pathways in brain function and provide an alternative perspective on the current postmortem literature.
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200
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Autophagic flux regulates microglial phenotype according to the time of oxygen-glucose deprivation/reperfusion. Int Immunopharmacol 2016; 39:140-148. [DOI: 10.1016/j.intimp.2016.06.030] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2015] [Revised: 06/11/2016] [Accepted: 06/27/2016] [Indexed: 12/29/2022]
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