201
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Wang XL, Li L. Microglia Regulate Neuronal Circuits in Homeostatic and High-Fat Diet-Induced Inflammatory Conditions. Front Cell Neurosci 2021; 15:722028. [PMID: 34720877 PMCID: PMC8549960 DOI: 10.3389/fncel.2021.722028] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 09/27/2021] [Indexed: 12/12/2022] Open
Abstract
Microglia are brain resident macrophages, which actively survey the surrounding microenvironment and promote tissue homeostasis under physiological conditions. During this process, microglia participate in synaptic remodeling, neurogenesis, elimination of unwanted neurons and cellular debris. The complex interplay between microglia and neurons drives the formation of functional neuronal connections and maintains an optimal neural network. However, activation of microglia induced by chronic inflammation increases synaptic phagocytosis and leads to neuronal impairment or death. Microglial dysfunction is implicated in almost all brain diseases and leads to long-lasting functional deficiency, such as hippocampus-related cognitive decline and hypothalamus-associated energy imbalance (i.e., obesity). High-fat diet (HFD) consumption triggers mediobasal hypothalamic microglial activation and inflammation. Moreover, HFD-induced inflammation results in cognitive deficits by triggering hippocampal microglial activation. Here, we have summarized the current knowledge of microglial characteristics and biological functions and also reviewed the molecular mechanism of microglia in shaping neural circuitries mainly related to cognition and energy balance in homeostatic and diet-induced inflammatory conditions.
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Affiliation(s)
- Xiao-Lan Wang
- Department of Nephrology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Lianjian Li
- Department of Surgery, Hubei Provincial Hospital of Traditional Chinese Medicine, Wuhan, China.,Hubei Province Academy of Traditional Chinese Medicine, Wuhan, China
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202
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Prineas JW, Parratt JDE. Multiple Sclerosis: Microglia, Monocytes, and Macrophage-Mediated Demyelination. J Neuropathol Exp Neurol 2021; 80:975-996. [PMID: 34553215 PMCID: PMC8557350 DOI: 10.1093/jnen/nlab083] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
This study examined the roles of microglia and monocytes in myelin destruction in patients with early multiple sclerosis (MS). Twenty-two cases were studied; the clinical duration was <9 weeks in 10 cases. Twenty myeloid cell subtypes or categories were identified including 2 cell types not known previously to occur in demyelinating diseases. Commencing myelin breakdown in plaques and in perivascular and subpial tissues occurred in the immediate presence of infiltrating monocytes and was effected by a homogeneous population of IgG-positive Fc receptor-bearing early phagocytes interacting with abnormal myelin. Oligodendrocyte apoptosis was observed in intact myelinated tissue bordering areas of active demyelination. Capillaries in the cerebral cortex plugged by large numbers of monocytes were common in acute cases of MS and in a patient with a neuromyelitis optica variant and extreme systemic recruitment of monocytes. In an MS patient with progressive disease, microglial nodules centered on MHC-II-positive capillaries plugged by monocytes were present in the cerebral cortex. This constitutes a new gray matter lesion in MS.
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Affiliation(s)
- John W Prineas
- From the Department of Medicine, University of Sydney, Camperdown, NSW, Australia
| | - John D E Parratt
- Department of Neurology, Royal North Shore Hospital, St. Leonards, NSW, Australia
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203
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Traumatic Brain Injury: An Age-Dependent View of Post-Traumatic Neuroinflammation and Its Treatment. Pharmaceutics 2021; 13:pharmaceutics13101624. [PMID: 34683918 PMCID: PMC8537402 DOI: 10.3390/pharmaceutics13101624] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 09/24/2021] [Accepted: 09/26/2021] [Indexed: 12/14/2022] Open
Abstract
Traumatic brain injury (TBI) is a leading cause of death and disability all over the world. TBI leads to (1) an inflammatory response, (2) white matter injuries and (3) neurodegenerative pathologies in the long term. In humans, TBI occurs most often in children and adolescents or in the elderly, and it is well known that immune responses and the neuroregenerative capacities of the brain, among other factors, vary over a lifetime. Thus, age-at-injury can influence the consequences of TBI. Furthermore, age-at-injury also influences the pharmacological effects of drugs. However, the post-TBI inflammatory, neuronal and functional consequences have been mostly studied in experimental young adult animal models. The specificity and the mechanisms underlying the consequences of TBI and pharmacological responses are poorly understood in extreme ages. In this review, we detail the variations of these age-dependent inflammatory responses and consequences after TBI, from an experimental point of view. We investigate the evolution of microglial, astrocyte and other immune cells responses, and the consequences in terms of neuronal death and functional deficits in neonates, juvenile, adolescent and aged male animals, following a single TBI. We also describe the pharmacological responses to anti-inflammatory or neuroprotective agents, highlighting the need for an age-specific approach to the development of therapies of TBI.
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204
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Fernández de Cossío L, Lacabanne C, Bordeleau M, Castino G, Kyriakakis P, Tremblay MÈ. Lipopolysaccharide-induced maternal immune activation modulates microglial CX3CR1 protein expression and morphological phenotype in the hippocampus and dentate gyrus, resulting in cognitive inflexibility during late adolescence. Brain Behav Immun 2021; 97:440-454. [PMID: 34343619 DOI: 10.1016/j.bbi.2021.07.025] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Revised: 07/25/2021] [Accepted: 07/28/2021] [Indexed: 12/26/2022] Open
Abstract
Inflammation during pregnancy can disturb brain development and lead to disorders in the progeny, including autism spectrum disorder and schizophrenia. However, the mechanism by which a prenatal, short-lived increase of cytokines results in adverse neurodevelopmental outcomes remains largely unknown. Microglia-the brain's resident immune-cells-stand as fundamental cellular mediators, being highly sensitive and responsive to immune signals, which also play key roles during normal development. The fractalkine signaling axis is a neuron-microglia communication mechanism used to regulate neurogenesis and network formation. Previously, we showed hippocampal reduction of fractalkine receptor (Cx3cr1) mRNA at postnatal day (P) 15 in male offspring exposed to maternal immune activation induced with lipopolysaccharide (LPS) during late gestation, which was concomitant to an increased dendritic spine density in the dentate gyrus, a neurogenic niche. The current study sought to evaluate the origin and impact of this reduced hippocampal Cx3cr1 mRNA expression on microglia and cognition. We found that microglial total cell number and density are not affected in the dorsal hippocampus and dentate gyrus, respectively, but that the microglial CX3CR1 protein is decreased in the hippocampus of LPS-male offspring at P15. Further characterization of microglial morphology in the dentate gyrus identified a more ameboid phenotype in LPS-exposed offspring, predominantly in males, at P15. We thus explored maternal plasma and fetal brain cytokines to understand the mechanism behind microglial priming, showing a robust immune activation in the mother at 2 and 4 hrs after LPS administration, while only IL-10 tended towards upregulation at 2 hrs after LPS in fetal brains. To evaluate the functional long-term consequences, we assessed learning and cognitive flexibility behavior during late adolescence, finding that LPS affects only the latter with a male predominance on perseveration. A CX3CR1 gene variant in humans that results in disrupted fractalkine signaling has been recently associated with an increased risk for neurodevelopmental disorders. We show that an acute immune insult during late gestation can alter fractalkine signaling by reducing the microglial CX3CR1 protein expression, highlighting neuron-microglial fractalkine signaling as a relevant target underlying the outcomes of environmental risk factors on neurodevelopmental disorders.
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Affiliation(s)
- Lourdes Fernández de Cossío
- Department of Neurosciences, University of California, La Jolla, CA, USA; Integrated Program in Neuroscience, McGill University, Montreal, QC, Canada.
| | - Chloé Lacabanne
- Integrated Program in Neuroscience, McGill University, Montreal, QC, Canada
| | - Maude Bordeleau
- Integrated Program in Neuroscience, McGill University, Montreal, QC, Canada; Axe Neurosciences, Centre de Recherche du CHU de Québec - Université Laval, Québec, QC, Canada
| | - Garance Castino
- Department of Biology, École Normale Supérieure de Lyon, Université de Lyon, Lyon, France
| | | | - Marie-Ève Tremblay
- Axe Neurosciences, Centre de Recherche du CHU de Québec - Université Laval, Québec, QC, Canada; Département de médecine moléculaire, Université Laval, Québec, QC, Canada; Department of Neurology and Neurosurgery, McGill University, Montréal, QC, Canada; Division of Medical Sciences, University of Victoria, Victoria, BC, Canada; Biochemistry and Molecular Biology, Faculty of Medicine, The University of British Colombia, Vancouver, BC, Canada.
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205
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Tremblay MÈ. Microglial functional alteration and increased diversity in the challenged brain: Insights into novel targets for intervention. Brain Behav Immun Health 2021; 16:100301. [PMID: 34589793 PMCID: PMC8474548 DOI: 10.1016/j.bbih.2021.100301] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 07/12/2021] [Accepted: 07/13/2021] [Indexed: 02/07/2023] Open
Abstract
Microglia are the resident immune cells of the central nervous system (CNS) parenchyma, which perform beneficial physiological roles across life. These immune cells actively maintain CNS health by clearing toxic debris and removing dysfunctional or degenerating cells. They also modify the wiring of neuronal circuits, by acting on the formation, modification, and elimination of synapses-the connections between neurons. Microglia furthermore recently emerged as highly diverse cells comprising several structural and functional states, indicating a far more critical involvement in orchestrating brain development, plasticity, behaviour, and cognition. Various environmental factors, together with the individual genetic predispositions, confer an increased risk for neurodevelopmental and neuropsychiatric disorders, as well as neurodegenerative diseases that include autism spectrum disorders, schizophrenia, major depressive disorder, and Alzheimer's disease, across life. Microglia are highly sensitive to chronic psychological stress, inadequate diet, viral/bacterial infection, pollution, and insufficient or altered sleep, especially during critical developmental periods, but also throughout life. These environmental challenges can compromise microglial physiological functions, resulting notably in defective neuronal circuit wiring, altered brain functional connectivity, and the onset of behavioral deficits into adolescence, adulthood, and aging. This short review provides a historical and technical perspective, notably focused on my contribution to the field, on how environmental challenges affect microglia, particularly their physiological functions, and increase their diversity, which provides novel targets for intervention.
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Affiliation(s)
- Marie-Ève Tremblay
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, QC, Canada
- Molecular Medicine Department, Université Laval, Québec City, QC, Canada
- Department of Neurology and Neurosurgery, McGill University, Montréal, QC, Canada
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
- The Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, BC, Canada
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206
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Ishikawa Y, Furuyashiki T. The impact of stress on immune systems and its relevance to mental illness. Neurosci Res 2021; 175:16-24. [PMID: 34606943 DOI: 10.1016/j.neures.2021.09.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 09/26/2021] [Accepted: 09/26/2021] [Indexed: 12/23/2022]
Abstract
Stress due to adverse and demanding conditions alters immune functions. How innate and adaptive immune systems respond to stress and affect neural processes remains unclear. Rodent studies have demonstrated crucial roles of stress-induced immune responses for depressive- and anxiety-like behaviors. In the periphery, stress evokes the mobilization of neutrophils and monocytes to the circulation via sympathetic nerves and glucocorticoids. These myeloid cells are thought to promote depressive- and anxiety-like behaviors by infiltrating the brain's perivascular space, releasing cytokines, and affecting vascular endothelial functions. In the brain, stress activates microglia via innate immune receptors TLR2/4. The activated microglia in the medial prefrontal cortex secrete cytokines and alter neuronal morphology and activity in their vicinity. In subcortical brain areas, prostaglandin (PG) E2 released from the activated microglia attenuates the dopaminergic projection to the medial prefrontal cortex via PGE receptor EP1. These multiple actions of microglia promote depressive-like behavior in concert. These rodent findings may be translatable to depression that clinical studies have associated with brain and peripheral inflammations. Understanding causal relationships between immune and neural alterations under stress might be exploitable to develop inflammation-targeting therapeutics for mental illness.
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Affiliation(s)
- Yuka Ishikawa
- Division of Pharmacology, Graduate School of Medicine, Kobe University, Kobe, Japan; Sumitomo Dainippon Pharma Co., Ltd., Osaka, Japan
| | - Tomoyuki Furuyashiki
- Division of Pharmacology, Graduate School of Medicine, Kobe University, Kobe, Japan; Japan Agency for Medical Research and Development, Tokyo, Japan.
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207
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Augusto-Oliveira M, Arrifano GP, Delage CI, Tremblay MÈ, Crespo-Lopez ME, Verkhratsky A. Plasticity of microglia. Biol Rev Camb Philos Soc 2021; 97:217-250. [PMID: 34549510 DOI: 10.1111/brv.12797] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 09/02/2021] [Accepted: 09/06/2021] [Indexed: 02/06/2023]
Abstract
Microglial cells are the scions of foetal macrophages which invade the neural tube early during embryogenesis. The nervous tissue environment instigates the phenotypic metamorphosis of foetal macrophages into idiosyncratic surveilling microglia, which are generally characterised by a small cell body and highly ramified motile processes that constantly scan the nervous tissue for signs of changes in homeostasis and allow microglia to perform crucial homeostatic functions. The surveilling microglial phenotype is evolutionarily conserved from early invertebrates to humans. Despite this evolutionary conservation, microglia show substantial heterogeneity in their gene and protein expression, as well as morphological appearance. These differences are age, region and context specific and reflect a high degree of plasticity underlying the life-long adaptation of microglia, supporting the exceptional adaptive capacity of the central nervous system. Microgliocytes are essential elements of cellular network formation and refinement in the developing nervous tissue. Several distinct patrolling modes of microglial processes contribute to the formation, modification, and pruning of synapses; to the support and protection of neurones through microglial-somatic junctions; and to the control of neuronal and axonal excitability by specific microglia-axonal contacts. In pathology, microglia undergo proliferation and reactive remodelling known as microgliosis, which is context dependent, yet represents an evolutionarily conserved defence response. Microgliosis results in the emergence of multiple disease and context-specific reactive states; in addition, neuropathology is associated with the appearance of specific protective or recovery microglial forms. In summary, the plasticity of microglia supports the development and functional activity of healthy nervous tissue and provides highly sophisticated defences against disease.
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Affiliation(s)
- Marcus Augusto-Oliveira
- Laboratório de Farmacologia Molecular, Instituto de Ciências Biológicas, Universidade Federal do Pará, 66075-110, Belém, Brazil
| | - Gabriela P Arrifano
- Laboratório de Farmacologia Molecular, Instituto de Ciências Biológicas, Universidade Federal do Pará, 66075-110, Belém, Brazil
| | - Charlotte Isabelle Delage
- Division of Medical Sciences, Medical Sciences Building, University of Victoria, Victoria, BC, V8P 5C2, Canada
| | - Marie-Ève Tremblay
- Division of Medical Sciences, Medical Sciences Building, University of Victoria, Victoria, BC, V8P 5C2, Canada.,Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, 2705 Boulevard Laurier, Québec City, QC, G1V 4G2, Canada.,Neurology and Neurosurgery Department, McGill University, 3801 University Street, Montreal, QC, H3A 2B4, Canada.,Department of Molecular Medicine, Université Laval, Pavillon Ferdinand-Vandry, Bureau 4835, 1050 Avenue de la Médecine, Québec City, QC, G1V 0A6, Canada.,Department of Biochemistry and Molecular Biology, The University of British Columbia, Life Sciences Center, 2350 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada
| | - Maria Elena Crespo-Lopez
- Laboratório de Farmacologia Molecular, Instituto de Ciências Biológicas, Universidade Federal do Pará, 66075-110, Belém, Brazil
| | - Alexei Verkhratsky
- Faculty of Life Sciences, The University of Manchester, Oxford Road, Manchester, M13 9PT, U.K.,Achucarro Center for Neuroscience, IKERBASQUE, 48011, Bilbao, Spain.,Department of Stem Cell Biology, State Research Institute Centre for Innovative Medicine, LT-01102, Vilnius, Lithuania
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208
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St-Pierre MK, Šimončičová E, Bögi E, Tremblay MÈ. Shedding Light on the Dark Side of the Microglia. ASN Neuro 2021; 12:1759091420925335. [PMID: 32443939 PMCID: PMC7249604 DOI: 10.1177/1759091420925335] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Microglia, the resident immune cells of the central nervous system, are not a
homogeneous population; their morphology, molecular profile, and even their
ultrastructure greatly vary from one cell to another. Recent advances in the
field of neuroimmunology have helped to demystify the enigma that currently
surrounds microglial heterogeneity. Indeed, numerous microglial subtypes have
been discovered such as the disease-associated microglia, neurodegenerative
phenotype, and Cd11c-positive developmental population. Another subtype is the
dark microglia (DM), a population defined by its ultrastructural changes
associated with cellular stress. Since their first characterization using
transmission electron microscopy, they have been identified in numerous disease
conditions, from mouse models of Alzheimer’s disease, schizophrenia, fractalkine
signaling deficiency to chronic stress, just to name a few. A recent study also
identified the presence of cells with a similar ultrastructure to the DM in
postmortem brain samples from schizophrenic patients,
underlining the importance of understanding the function of these cells. In this
minireview, we aim to summarize the current knowledge on the DM, from their
initial ultrastructural characterization to their documentation in various
pathological contexts across multiple species. We will also highlight the
current limitations surrounding the study of these cells and the future that
awaits the DM.
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Affiliation(s)
| | - Eva Šimončičová
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval.,Department of Pharmacology, Jessenius Faculty of Medicine, Comenius University, Martin, Slovak Republic.,Institute of Experimental Pharmacology and Toxicology, Centre of Experimental Medicine, Slovak Academy of Sciences, Bratislava, Slovak Republic
| | - Eszter Bögi
- Department of Pharmacology, Jessenius Faculty of Medicine, Comenius University, Martin, Slovak Republic
| | - Marie-Ève Tremblay
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval
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209
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Rayasam A, Fukuzaki Y, Vexler ZS. Microglia-leucocyte axis in cerebral ischaemia and inflammation in the developing brain. Acta Physiol (Oxf) 2021; 233:e13674. [PMID: 33991400 DOI: 10.1111/apha.13674] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 05/06/2021] [Accepted: 05/08/2021] [Indexed: 12/13/2022]
Abstract
Development of the Central Nervous System (CNS) is reliant on the proper function of numerous intricately orchestrated mechanisms that mature independently, including constant communication between the CNS and the peripheral immune system. This review summarizes experimental knowledge of how cerebral ischaemia in infants and children alters physiological communication between leucocytes, brain immune cells, microglia and the neurovascular unit (NVU)-the "microglia-leucocyte axis"-and contributes to acute and long-term brain injury. We outline physiological development of CNS barriers in relation to microglial and leucocyte maturation and the plethora of mechanisms by which microglia and peripheral leucocytes communicate during postnatal period, including receptor-mediated and intracellular inflammatory signalling, lipids, soluble factors and extracellular vesicles. We focus on the "microglia-leucocyte axis" in rodent models of most common ischaemic brain diseases in the at-term infants, hypoxic-ischaemic encephalopathy (HIE) and focal arterial stroke and discuss commonalities and distinctions of immune-neurovascular mechanisms in neonatal and childhood stroke compared to stroke in adults. Given that hypoxic and ischaemic brain damage involve Toll-like receptor (TLR) activation, we discuss the modulatory role of viral and bacterial TLR2/3/4-mediated infection in HIE, perinatal and childhood stroke. Furthermore, we provide perspective of the dynamics and contribution of the axis in cerebral ischaemia depending on the CNS maturational stage at the time of insult, and modulation independently and in consort by individual axis components and in a sex dependent ways. Improved understanding on how to modify crosstalk between microglia and leucocytes will aid in developing age-appropriate therapies for infants and children who suffered cerebral ischaemia.
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Affiliation(s)
- Aditya Rayasam
- Department of Neurology University of California San Francisco San Francisco CA USA
| | - Yumi Fukuzaki
- Department of Neurology University of California San Francisco San Francisco CA USA
| | - Zinaida S. Vexler
- Department of Neurology University of California San Francisco San Francisco CA USA
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210
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Jackson-Cowan L, Cole EF, Arbiser JL, Silverberg JI, Lawley LP. TH2 sensitization in the skin-gut-brain axis: How early-life Th2-mediated inflammation may negatively perpetuate developmental and psychologic abnormalities. Pediatr Dermatol 2021; 38:1032-1039. [PMID: 34338364 DOI: 10.1111/pde.14657] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
We recently reported children with comorbid atopic dermatitis (AD), asthma, allergic rhinitis, and food allergies displaying a 2.7-fold increase in developmental delays.2 To this end, we hypothesize unregulated increases in T helper-2 (Th2)-driven inflammation, such as those seen in atopic diseases, can exert deleterious effects on the developing brain. Recognizing that available information is incomplete and that many potential associations are not firmly established, we speculate these effects underlie the association between Th2 sensitization and cognitive dysfunction in children. In this review, we explore the role of Th2 sensitization in the skin-gut-brain axis and explain how it can lead to reduced connectivity and transmission in the developing brain. With a focus on AD, we explore the association between Th2 sensitization and developmental abnormalities such as developmental delays, memory impairment, autism spectrum disorder (ASD), and epilepsy/seizures. As such, we review the available literature to examine the impact of increased IL-4 exposure in early life on the brain. We explore the possible association between Th2 sensitization and psychologic dysfunction such as attention-deficit/hyperactivity disorder (ADHD), depression, anxiety, and suicidal ideation. We also examine the impact that increased exposure to glucocorticoids and neurotrophins in early life exerts on the developing brain. Last, we discuss future directions for the advancement of our knowledge as a scientific community including possible interventions to reduce developmental and psychologic aberrations in children.
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Affiliation(s)
- LaDonya Jackson-Cowan
- AU/UGA Medical Partnership, The Medical College of Georgia at Augusta University, University of Georgia College of Pharmacy, Athens, GA, USA
| | - Emily F Cole
- Department of Dermatology, Emory University School of Medicine, Atlanta, GA, USA
| | - Jack L Arbiser
- Department of Dermatology, Emory University School of Medicine, Atlanta, GA, USA
| | - Jonathan I Silverberg
- Department of Dermatology, George Washington University School of Medicine and Health Sciences, Washington, DC, USA
| | - Leslie P Lawley
- Department of Dermatology, Emory University School of Medicine, Atlanta, GA, USA
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211
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Ashwal S, Siebold L, Krueger AC, Wilson CG. Post-traumatic Neuroinflammation: Relevance to Pediatrics. Pediatr Neurol 2021; 122:50-58. [PMID: 34304972 DOI: 10.1016/j.pediatrneurol.2021.04.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 04/19/2021] [Accepted: 04/20/2021] [Indexed: 10/21/2022]
Abstract
Both detrimental and beneficial effects of post-traumatic neuroinflammation have become a major research focus as they offer the potential for immediate as well as delayed targeted reparative therapies. Understanding the complex interactions of central and peripheral immunocompetent cells as well as their mediators on brain injury and recovery is complicated by the temporal, regional, and developmental differences in their response to injuries. Microglia, the brain-resident macrophages, have become central in these investigations as they serve a major surveillance function, have the ability to react swiftly to injury, recruit various cellular and chemical mediators, and monitor the reparative/degenerative processes. In this review we describe selected aspects of this burgeoning literature, describing the critical role of cytokines and chemokines, microglia, advances in neuroimaging, genetics and fractal morphology analysis, our research efforts in this area, and selected aspects of pediatric post-traumatic neuroinflammation.
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Affiliation(s)
- Stephen Ashwal
- Department of Pediatrics, Loma Linda University, School of Medicine, Loma Linda, California.
| | - Lorraine Siebold
- Department of Pediatrics, Loma Linda University, School of Medicine, Loma Linda, California
| | - A Camille Krueger
- Department of Pediatrics, Loma Linda University, School of Medicine, Loma Linda, California
| | - Christopher G Wilson
- Department of Pediatrics, Loma Linda University, School of Medicine, Loma Linda, California
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212
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IGF1 Gene Therapy Reversed Cognitive Deficits and Restored Hippocampal Alterations After Chronic Spinal Cord Injury. Mol Neurobiol 2021; 58:6186-6202. [PMID: 34463925 DOI: 10.1007/s12035-021-02545-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Accepted: 08/22/2021] [Indexed: 10/20/2022]
Abstract
The hippocampus is implicated in the generation of memory and learning, processes which involve extensive neuroplasticity. The generation of hippocampal adult-born neurons is particularly regulated by glial cells of the neurogenic niche and the surrounding microenvironment. Interestingly, recent evidence has shown that spinal cord injury (SCI) in rodents leads to hippocampal neuroinflammation, neurogenesis reduction, and cognitive impairments. In this scenario, the aim of this work was to evaluate whether an adenoviral vector expressing IGF1 could reverse hippocampal alterations and cognitive deficits after chronic SCI. SCI caused neurogenesis reduction and impairments of both recognition and working memories. We also found that SCI increased the number of hypertrophic arginase-1 negative microglia concomitant with the decrease of the number of ramified surveillance microglia in the hilus, molecular layer, and subgranular zone of the dentate gyrus. RAd-IGF1 treatment restored neurogenesis and improved recognition and working memory impairments. In addition, RAd-IGF1 gene therapy modulated differentially hippocampal regions. In the hilus and molecular layer, IGF1 gene therapy recovered the number of surveillance microglia coincident with a reduction of hypertrophic microglia cell number. However, in the neurogenic niche, IGF1 reduced the number of ramified microglia and increased the number of hypertrophic microglia, which as a whole expressed arginase-1. In summary, RAd-IGF1 gene therapy might surge as a new therapeutic strategy for patients with hippocampal microglial alterations and cognitive deficits such as those with spinal cord injury and other neurodegenerative diseases.
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213
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Hohsfield LA, Najafi AR, Ghorbanian Y, Soni N, Crapser J, Figueroa Velez DX, Jiang S, Royer SE, Kim SJ, Henningfield CM, Anderson A, Gandhi SP, Mortazavi A, Inlay MA, Green KN. Subventricular zone/white matter microglia reconstitute the empty adult microglial niche in a dynamic wave. eLife 2021; 10:66738. [PMID: 34423781 PMCID: PMC8425950 DOI: 10.7554/elife.66738] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 08/22/2021] [Indexed: 02/06/2023] Open
Abstract
Microglia, the brain’s resident myeloid cells, play central roles in brain defense, homeostasis, and disease. Using a prolonged colony-stimulating factor 1 receptor inhibitor (CSF1Ri) approach, we report an unprecedented level of microglial depletion and establish a model system that achieves an empty microglial niche in the adult brain. We identify a myeloid cell that migrates from the subventricular zone and associated white matter areas. Following CSF1Ri, these amoeboid cells migrate radially and tangentially in a dynamic wave filling the brain in a distinct pattern, to replace the microglial-depleted brain. These repopulating cells are enriched in disease-associated microglia genes and exhibit similar phenotypic and transcriptional profiles to white-matter-associated microglia. Our findings shed light on the overlapping and distinct functional complexity and diversity of myeloid cells of the CNS and provide new insight into repopulating microglia function and dynamics in the mouse brain.
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Affiliation(s)
- Lindsay A Hohsfield
- Department of Neurobiology and Behavior, Irvine, United States.,Institute for Memory Impairments and Neurological Disorders, Irvine, United States
| | - Allison R Najafi
- Department of Neurobiology and Behavior, Irvine, United States.,Institute for Memory Impairments and Neurological Disorders, Irvine, United States
| | - Yasamine Ghorbanian
- Sue and Bill Gross Stem Cell Research Center, Irvine, United States.,Department of Molecular Biology and Biochemistry, Irvine, United States
| | - Neelakshi Soni
- Department of Neurobiology and Behavior, Irvine, United States.,Institute for Memory Impairments and Neurological Disorders, Irvine, United States
| | - Joshua Crapser
- Department of Neurobiology and Behavior, Irvine, United States.,Institute for Memory Impairments and Neurological Disorders, Irvine, United States
| | | | - Shan Jiang
- Department of Developmental and Cell Biology, Irvine, United States
| | - Sarah E Royer
- Department of Neurobiology and Behavior, Irvine, United States.,Sue and Bill Gross Stem Cell Research Center, Irvine, United States.,Department of Anatomy and Neurobiology, Irvine, United States
| | - Sung Jin Kim
- Department of Neurobiology and Behavior, Irvine, United States.,Institute for Memory Impairments and Neurological Disorders, Irvine, United States
| | - Caden M Henningfield
- Department of Neurobiology and Behavior, Irvine, United States.,Institute for Memory Impairments and Neurological Disorders, Irvine, United States
| | - Aileen Anderson
- Department of Neurobiology and Behavior, Irvine, United States.,Institute for Memory Impairments and Neurological Disorders, Irvine, United States.,Sue and Bill Gross Stem Cell Research Center, Irvine, United States.,Department of Anatomy and Neurobiology, Irvine, United States.,Department of Physical Medicine & Rehabilitation, University of California, Irvine, Irvine, United States
| | - Sunil P Gandhi
- Department of Neurobiology and Behavior, Irvine, United States
| | - Ali Mortazavi
- Department of Developmental and Cell Biology, Irvine, United States
| | - Matthew A Inlay
- Department of Neurobiology and Behavior, Irvine, United States.,Sue and Bill Gross Stem Cell Research Center, Irvine, United States.,Department of Molecular Biology and Biochemistry, Irvine, United States
| | - Kim N Green
- Department of Neurobiology and Behavior, Irvine, United States.,Institute for Memory Impairments and Neurological Disorders, Irvine, United States
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214
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Augusto-Oliveira M, Verkhratsky A. Lifestyle-dependent microglial plasticity: training the brain guardians. Biol Direct 2021; 16:12. [PMID: 34353376 PMCID: PMC8340437 DOI: 10.1186/s13062-021-00297-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Accepted: 07/29/2021] [Indexed: 02/07/2023] Open
Abstract
Lifestyle is one of the most powerful instruments shaping mankind; the lifestyle includes many aspects of interactions with the environment, from nourishment and education to physical activity and quality of sleep. All these factors taken in complex affect neuroplasticity and define brain performance and cognitive longevity. In particular, physical exercise, exposure to enriched environment and dieting act through complex modifications of microglial cells, which change their phenotype and modulate their functional activity thus translating lifestyle events into remodelling of brain homoeostasis and reshaping neural networks ultimately enhancing neuroprotection and cognitive longevity.
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Affiliation(s)
- Marcus Augusto-Oliveira
- Laboratório de Farmacologia Molecular, Instituto de Ciências Biológicas, Universidade Federal Do Pará, Belém, 66075-110, Brazil.
| | - Alexei Verkhratsky
- Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, M13 9PT, UK. .,Department of Stem Cell Biology, State Research Institute Centre for Innovative Medicine, 01102, Vilnius, Lithuania. .,Achucarro Center for Neuroscience, IKERBASQUE, Basque Foundation for Science, 48011, Bilbao, Spain. .,Department of Neurosciences, University of the Basque Country UPV/EHU and CIBERNED, Leioa, Spain.
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215
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Neurotoxic Effects of Neonicotinoids on Mammals: What Is There beyond the Activation of Nicotinic Acetylcholine Receptors?-A Systematic Review. Int J Mol Sci 2021; 22:ijms22168413. [PMID: 34445117 PMCID: PMC8395098 DOI: 10.3390/ijms22168413] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 07/29/2021] [Accepted: 08/02/2021] [Indexed: 02/07/2023] Open
Abstract
Neonicotinoids are a class of insecticides that exert their effect through a specific action on neuronal nicotinic acetylcholine receptors (nAChRs). The success of these insecticides is due to this mechanism of action, since they act as potent agonists of insect nAChRs, presenting low affinity for vertebrate nAChRs, which reduces potential toxic risk and increases safety for non-target species. However, although neonicotinoids are considered safe, their presence in the environment could increase the risk of exposure and toxicity. On the other hand, although neonicotinoids have low affinity for mammalian nAChRs, the large quantity, variety, and ubiquity of these receptors, combined with its diversity of functions, raises the question of what effects these insecticides can produce in non-target species. In the present systematic review, we investigate the available evidence on the biochemical and behavioral effects of neonicotinoids on the mammalian nervous system. In general, exposure to neonicotinoids at an early age alters the correct neuronal development, with decreases in neurogenesis and alterations in migration, and induces neuroinflammation. In adulthood, neonicotinoids induce neurobehavioral toxicity, these effects being associated with their modulating action on nAChRs, with consequent neurochemical alterations. These alterations include decreased expression of nAChRs, modifications in acetylcholinesterase activity, and significant changes in the function of the nigrostriatal dopaminergic system. All these effects can lead to the activation of a series of intracellular signaling pathways that generate oxidative stress, neuroinflammation and, finally, neuronal death. Neonicotinoid-induced changes in nAChR function could be responsible for most of the effects observed in the different studies.
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216
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Abdul Y, Li W, Ward R, Abdelsaid M, Hafez S, Dong G, Jamil S, Wolf V, Johnson MH, Fagan SC, Ergul A. Deferoxamine Treatment Prevents Post-Stroke Vasoregression and Neurovascular Unit Remodeling Leading to Improved Functional Outcomes in Type 2 Male Diabetic Rats: Role of Endothelial Ferroptosis. Transl Stroke Res 2021; 12:615-630. [PMID: 32875455 PMCID: PMC7917163 DOI: 10.1007/s12975-020-00844-7] [Citation(s) in RCA: 63] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 08/13/2020] [Accepted: 08/19/2020] [Indexed: 12/28/2022]
Abstract
It is a clinically well-established fact that patients with diabetes have very poor stroke outcomes. Yet, the underlying mechanisms remain largely unknown. Our previous studies showed that male diabetic animals show greater hemorrhagic transformation (HT), profound loss of cerebral vasculature in the recovery period, and poor sensorimotor and cognitive outcomes after ischemic stroke. This study aimed to determine the impact of iron chelation with deferoxamine (DFX) on (1) cerebral vascularization patterns and (2) functional outcomes after stroke in control and diabetic rats. After 8 weeks of type 2 diabetes induced by a combination of high-fat diet and low-dose streptozotocin, male control and diabetic animals were subjected to thromboembolic middle cerebral artery occlusion (MCAO) and randomized to vehicle, DFX, or tPA/DFX and followed for 14 days with behavioral tests. Vascular indices (vascular volume and surface area), neurovascular remodeling (AQP4 polarity), and microglia activation were measured. Brain microvascular endothelial cells (BMVEC) from control and diabetic animals were evaluated for the impact of DFX on ferroptotic cell death. DFX treatment prevented vasoregression and microglia activation while improving AQP4 polarity as well as blood-brain barrier permeability by day 14 in diabetic rats. These pathological changes were associated with improvement of functional outcomes. In control rats, DFX did not have an effect. Iron increased markers of ferroptosis and lipid reactive oxygen species (ROS) to a greater extent in BMVECs from diabetic animals, and this was prevented by DFX. These results strongly suggest that (1) HT impacts post-stroke vascularization patterns and recovery responses in diabetes, (2) treatment of bleeding with iron chelation has differential effects on outcomes in comorbid disease conditions, and (3) iron chelation and possibly inhibition of ferroptosis may provide a novel disease-modifying therapeutic strategy in the prevention of post-stroke cognitive impairment in diabetes.
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Affiliation(s)
- Yasir Abdul
- Ralph H. Johnson VA Medical Center, Charleston, SC, USA
- Department of Pathology and Laboratory Sciences, Medical University of South Carolina, 171 Ashley Ave. MSC 908, Charleston, SC, 29425, USA
| | - Weiguo Li
- Ralph H. Johnson VA Medical Center, Charleston, SC, USA
- Department of Pathology and Laboratory Sciences, Medical University of South Carolina, 171 Ashley Ave. MSC 908, Charleston, SC, 29425, USA
| | - Rebecca Ward
- Department of Medicine, Massachusetts General Hospital, Boston, MA, USA
| | | | - Sherif Hafez
- Department of Pharmaceutical Sciences, College of Pharmacy, Larkin University, Miami, FL, USA
| | - Guangkuo Dong
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta, GA, USA
| | - Sarah Jamil
- Ralph H. Johnson VA Medical Center, Charleston, SC, USA
- Department of Pathology and Laboratory Sciences, Medical University of South Carolina, 171 Ashley Ave. MSC 908, Charleston, SC, 29425, USA
| | - Victoria Wolf
- Ralph H. Johnson VA Medical Center, Charleston, SC, USA
- Department of Pathology and Laboratory Sciences, Medical University of South Carolina, 171 Ashley Ave. MSC 908, Charleston, SC, 29425, USA
| | - Maribeth H Johnson
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta, GA, USA
| | - Susan C Fagan
- Program in Clinical and Experimental Therapeutics, University of Georgia College of Pharmacy, Augusta, GA, USA
- Charlie Norwood Veterans Affairs Medical Center, Augusta, GA, USA
| | - Adviye Ergul
- Ralph H. Johnson VA Medical Center, Charleston, SC, USA.
- Department of Pathology and Laboratory Sciences, Medical University of South Carolina, 171 Ashley Ave. MSC 908, Charleston, SC, 29425, USA.
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217
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Liang X, Wu H, Colt M, Guo X, Pluimer B, Zeng J, Dong S, Zhao Z. Microglia and its Genetics in Alzheimer's Disease. Curr Alzheimer Res 2021; 18:676-688. [PMID: 34749609 DOI: 10.2174/1567205018666211105140732] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Revised: 06/30/2021] [Accepted: 07/03/2021] [Indexed: 12/27/2022]
Abstract
Alzheimer's Disease (AD) is the most prevalent form of dementia across the world. While its discovery and pathological manifestations are centered on protein aggregations of amyloid- beta (Aβ) and hyperphosphorylated tau protein, neuroinflammation has emerged in the last decade as a main component of the disease in terms of both pathogenesis and progression. As the main innate immune cell type in the central nervous system (CNS), microglia play a very important role in regulating neuroinflammation, which occurs commonly in neurodegenerative conditions, including AD. Under inflammatory response, microglia undergo morphological changes and status transition from homeostatic to activated forms. Different microglia subtypes displaying distinct genetic profiles have been identified in AD, and these signatures often link to AD risk genes identified from the genome-wide association studies (GWAS), such as APOE and TREM2. Furthermore, many AD risk genes are highly enriched in microglia and specifically influence the functions of microglia in pathogenesis, e.g. releasing inflammatory cytokines and clearing Aβ. Therefore, building up a landscape of these risk genes in microglia, based on current preclinical studies and in the context of their pathogenic or protective effects, would largely help us to understand the complex etiology of AD and provide new insight into the unmet need for effective treatment.
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Affiliation(s)
- Xinyan Liang
- Center for Neurodegeneration and Regeneration, Zilkha Neurogenetic Institute and Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, California, 90033,United States
| | - Haijian Wu
- Center for Neurodegeneration and Regeneration, Zilkha Neurogenetic Institute and Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, California, 90033,United States
| | - Mark Colt
- Center for Neurodegeneration and Regeneration, Zilkha Neurogenetic Institute and Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, California, 90033,United States
| | - Xinying Guo
- Center for Neurodegeneration and Regeneration, Zilkha Neurogenetic Institute and Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, California, 90033,United States
| | - Brock Pluimer
- Center for Neurodegeneration and Regeneration, Zilkha Neurogenetic Institute and Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, California, 90033,United States
| | - Jianxiong Zeng
- Center for Neurodegeneration and Regeneration, Zilkha Neurogenetic Institute and Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, California, 90033,United States
| | - Shupeng Dong
- Center for Neurodegeneration and Regeneration, Zilkha Neurogenetic Institute and Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, California, 90033,United States
| | - Zhen Zhao
- Center for Neurodegeneration and Regeneration, Zilkha Neurogenetic Institute and Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, California, 90033,United States
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218
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Acharjee S, Gordon PMK, Lee BH, Read J, Workentine ML, Sharkey KA, Pittman QJ. Characterization of microglial transcriptomes in the brain and spinal cord of mice in early and late experimental autoimmune encephalomyelitis using a RiboTag strategy. Sci Rep 2021; 11:14319. [PMID: 34253764 PMCID: PMC8275680 DOI: 10.1038/s41598-021-93590-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Accepted: 06/25/2021] [Indexed: 12/29/2022] Open
Abstract
Microglia play an important role in the pathogenesis of multiple sclerosis and the mouse model of MS, experimental autoimmune encephalomyelitis (EAE). To more fully understand the role of microglia in EAE we characterized microglial transcriptomes before the onset of motor symptoms (pre-onset) and during symptomatic EAE. We compared the transcriptome in brain, where behavioral changes are initiated, and spinal cord, where damage is revealed as motor and sensory deficits. We used a RiboTag strategy to characterize ribosome-bound mRNA only in microglia without incurring possible transcriptional changes after cell isolation. Brain and spinal cord samples clustered separately at both stages of EAE, indicating regional heterogeneity. Differences in gene expression were observed in the brain and spinal cord of pre-onset and symptomatic animals with most profound effects in the spinal cord of symptomatic animals. Canonical pathway analysis revealed changes in neuroinflammatory pathways, immune functions and enhanced cell division in both pre-onset and symptomatic brain and spinal cord. We also observed a continuum of many pathways at pre-onset stage that continue into the symptomatic stage of EAE. Our results provide additional evidence of regional and temporal heterogeneity in microglial gene expression patterns that may help in understanding mechanisms underlying various symptomology in MS.
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Affiliation(s)
- Shaona Acharjee
- Hotchkiss Brain Institute, Snyder Institute for Chronic Diseases, Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary, AB, T2N 4N1, Canada
| | - Paul M K Gordon
- Centre for Health Genomics and Informatics, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Benjamin H Lee
- Hotchkiss Brain Institute, Snyder Institute for Chronic Diseases, Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary, AB, T2N 4N1, Canada
| | - Justin Read
- Hotchkiss Brain Institute, Snyder Institute for Chronic Diseases, Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary, AB, T2N 4N1, Canada
| | - Matthew L Workentine
- Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Keith A Sharkey
- Hotchkiss Brain Institute, Snyder Institute for Chronic Diseases, Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary, AB, T2N 4N1, Canada
| | - Quentin J Pittman
- Hotchkiss Brain Institute, Snyder Institute for Chronic Diseases, Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary, AB, T2N 4N1, Canada.
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219
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Carvalho-Paulo D, Bento Torres Neto J, Filho CS, de Oliveira TCG, de Sousa AA, dos Reis RR, dos Santos ZA, de Lima CM, de Oliveira MA, Said NM, Freitas SF, Sosthenes MCK, Gomes GF, Henrique EP, Pereira PDC, de Siqueira LS, de Melo MAD, Guerreiro Diniz C, Magalhães NGDM, Diniz JAP, Vasconcelos PFDC, Diniz DG, Anthony DC, Sherry DF, Brites D, Picanço Diniz CW. Microglial Morphology Across Distantly Related Species: Phylogenetic, Environmental and Age Influences on Microglia Reactivity and Surveillance States. Front Immunol 2021; 12:683026. [PMID: 34220831 PMCID: PMC8250867 DOI: 10.3389/fimmu.2021.683026] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Accepted: 05/31/2021] [Indexed: 12/16/2022] Open
Abstract
Microglial immunosurveillance of the brain parenchyma to detect local perturbations in homeostasis, in all species, results in the adoption of a spectrum of morphological changes that reflect functional adaptations. Here, we review the contribution of these changes in microglia morphology in distantly related species, in homeostatic and non-homeostatic conditions, with three principal goals (1): to review the phylogenetic influences on the morphological diversity of microglia during homeostasis (2); to explore the impact of homeostatic perturbations (Dengue virus challenge) in distantly related species (Mus musculus and Callithrix penicillata) as a proxy for the differential immune response in small and large brains; and (3) to examine the influences of environmental enrichment and aging on the plasticity of the microglial morphological response following an immunological challenge (neurotropic arbovirus infection). Our findings reveal that the differences in microglia morphology across distantly related species under homeostatic condition cannot be attributed to the phylogenetic origin of the species. However, large and small brains, under similar non-homeostatic conditions, display differential microglial morphological responses, and we argue that age and environment interact to affect the microglia morphology after an immunological challenge; in particular, mice living in an enriched environment exhibit a more efficient immune response to the virus resulting in earlier removal of the virus and earlier return to the homeostatic morphological phenotype of microglia than it is observed in sedentary mice.
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Affiliation(s)
- Dario Carvalho-Paulo
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém, Brazil
| | - João Bento Torres Neto
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém, Brazil
- Faculdade de Fisioterapia e Terapia Ocupacional, Universidade Federal do Pará, Belém, Brazil
| | - Carlos Santos Filho
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém, Brazil
| | - Thais Cristina Galdino de Oliveira
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém, Brazil
| | - Aline Andrade de Sousa
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém, Brazil
| | - Renata Rodrigues dos Reis
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém, Brazil
| | - Zaire Alves dos Santos
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém, Brazil
| | - Camila Mendes de Lima
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém, Brazil
| | - Marcus Augusto de Oliveira
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém, Brazil
| | - Nivin Mazen Said
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém, Brazil
| | - Sinara Franco Freitas
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém, Brazil
| | - Marcia Consentino Kronka Sosthenes
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém, Brazil
| | - Giovanni Freitas Gomes
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém, Brazil
| | - Ediely Pereira Henrique
- Laboratório de Biologia Molecular e Neuroecologia, Instituto Federal de Educação Ciência e Tecnologia do Pará, Bragança, Brazil
| | - Patrick Douglas Côrrea Pereira
- Laboratório de Biologia Molecular e Neuroecologia, Instituto Federal de Educação Ciência e Tecnologia do Pará, Bragança, Brazil
| | - Lucas Silva de Siqueira
- Laboratório de Biologia Molecular e Neuroecologia, Instituto Federal de Educação Ciência e Tecnologia do Pará, Bragança, Brazil
| | - Mauro André Damasceno de Melo
- Laboratório de Biologia Molecular e Neuroecologia, Instituto Federal de Educação Ciência e Tecnologia do Pará, Bragança, Brazil
| | - Cristovam Guerreiro Diniz
- Laboratório de Biologia Molecular e Neuroecologia, Instituto Federal de Educação Ciência e Tecnologia do Pará, Bragança, Brazil
| | - Nara Gyzely de Morais Magalhães
- Laboratório de Biologia Molecular e Neuroecologia, Instituto Federal de Educação Ciência e Tecnologia do Pará, Bragança, Brazil
| | | | - Pedro Fernando da Costa Vasconcelos
- Dep. de Arbovirologia e Febres Hemorrágicas, Instituto Evandro Chagas, Belém, Brazil
- Departamento de Patologia, Universidade do Estado do Pará, Belém, Brazil
| | - Daniel Guerreiro Diniz
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém, Brazil
- Laboratório de Microscopia Eletrônica, Instituto Evandro Chagas, Belém, Brazil
| | | | - David Francis Sherry
- Department of Psychology, Advanced Facility for Avian Research, University of Western Ontario, London, ON, Canada
| | - Dora Brites
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Lisbon, Portugal
- Department of Pharmaceutical Sciences and Medicines, Faculty of Pharmacy, Universidade de Lisboa, Lisbon, Portugal
| | - Cristovam Wanderley Picanço Diniz
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém, Brazil
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220
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Awogbindin IO, Ben-Azu B, Olusola BA, Akinluyi ET, Adeniyi PA, Di Paolo T, Tremblay MÈ. Microglial Implications in SARS-CoV-2 Infection and COVID-19: Lessons From Viral RNA Neurotropism and Possible Relevance to Parkinson's Disease. Front Cell Neurosci 2021; 15:670298. [PMID: 34211370 PMCID: PMC8240959 DOI: 10.3389/fncel.2021.670298] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Accepted: 05/05/2021] [Indexed: 12/24/2022] Open
Abstract
Since December 2019, humankind has been experiencing a ravaging severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak, the second coronavirus pandemic in a decade after the Middle East respiratory syndrome coronavirus (MERS-CoV) disease in 2012. Infection with SARS-CoV-2 results in Coronavirus disease 2019 (COVID-19), which is responsible for over 3.1 million deaths worldwide. With the emergence of a second and a third wave of infection across the globe, and the rising record of multiple reinfections and relapses, SARS-CoV-2 infection shows no sign of abating. In addition, it is now evident that SARS-CoV-2 infection presents with neurological symptoms that include early hyposmia, ischemic stroke, meningitis, delirium and falls, even after viral clearance. This may suggest chronic or permanent changes to the neurons, glial cells, and/or brain vasculature in response to SARS-CoV-2 infection or COVID-19. Within the central nervous system (CNS), microglia act as the central housekeepers against altered homeostatic states, including during viral neurotropic infections. In this review, we highlight microglial responses to viral neuroinfections, especially those with a similar genetic composition and route of entry as SARS-CoV-2. As the primary sensor of viral infection in the CNS, we describe the pathogenic and neuroinvasive mechanisms of RNA viruses and SARS-CoV-2 vis-à-vis the microglial means of viral recognition. Responses of microglia which may culminate in viral clearance or immunopathology are also covered. Lastly, we further discuss the implication of SARS-CoV-2 CNS invasion on microglial plasticity and associated long-term neurodegeneration. As such, this review provides insight into some of the mechanisms by which microglia could contribute to the pathophysiology of post-COVID-19 neurological sequelae and disorders, including Parkinson's disease, which could be pervasive in the coming years given the growing numbers of infected and re-infected individuals globally.
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Affiliation(s)
- Ifeoluwa O. Awogbindin
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
- Neuroimmunology Group, Molecular Drug Metabolism and Toxicology Laboratory, Department of Biochemistry, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Benneth Ben-Azu
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
- Neuropharmacology Unit, Department of Pharmacology and Therapeutics, Faculty of Basic Medical Sciences, College of Health Sciences, Delta State University, Abraka, Nigeria
| | - Babatunde A. Olusola
- Department of Virology, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Elizabeth T. Akinluyi
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
- Department of Pharmacology and Therapeutics, College of Medicine and Health Sciences, Afe Babalola University, Ado-Ekiti, Nigeria
| | - Philip A. Adeniyi
- Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA, United States
| | - Therese Di Paolo
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, QC, Canada
- Faculté de Pharmacie, Université Laval, Québec, QC, Canada
| | - Marie-Ève Tremblay
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, QC, Canada
- Neurology and Neurosurgery Department, McGill University, Montréal, QC, Canada
- Department of Molecular Medicine, Université Laval, Québec, QC, Canada
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC, Canada
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221
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Ohgomori T, Iinuma K, Yamada J, Jinno S. A unique subtype of ramified microglia associated with synapses in the rat hippocampus. Eur J Neurosci 2021; 54:4740-4754. [PMID: 34110047 DOI: 10.1111/ejn.15330] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 05/20/2021] [Accepted: 05/24/2021] [Indexed: 12/13/2022]
Abstract
To date, a number of studies have reported the heterogeneity of activated microglia. However, there is increasing evidence suggests that ramified, so-called resting, microglia may also be heterogeneous, and they may play diverse roles in normal brain homeostasis. Here, we found that both 5D4 keratan sulfate epitope-positive (5D4+ ) and 5D4-negative (5D4- ) microglia coexisted in the hippocampus of normal rats, while all microglia were negative for the 5D4 epitope in the hippocampus of normal mice. We thus aimed to determine the potential heterogeneity of microglia related to the 5D4 epitope in the normal rat hippocampus. The optical disector analysis showed that the densities of 5D4+ microglia were higher in the stratum oriens of the CA3 region than in other layers and regions. Although both 5D4+ and 5D4- microglia exhibited a ramified morphology, the three-dimensional reconstruction analysis showed that the node numbers, end numbers, and complexity of processes were higher in 5D4+ than in 5D4- microglia. The linear discriminant analysis showed that 5D4+ and 5D4- microglia can be classified into distinct morphometric subtypes. The ratios of contact between synaptic boutons and microglial processes were higher in 5D4+ than in 5D4- microglia. The gene expressions of pro-inflammatory cytokine interleukin-1β and purinergic receptor P2Y12 (P2Y12 R) were higher in 5D4+ than in 5D4- microglia. Together, these results indicate that at least two different subtypes of ramified microglia coexist in the normal rat hippocampus and also suggest that 5D4+ microglia may represent a unique subtype associated with synapses.
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Affiliation(s)
- Tomohiro Ohgomori
- Department of Anatomy and Neuroscience, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.,Department of Rehabilitation, Osaka Kawasaki Rehabilitation University, Kaizuka, Japan
| | - Kyoko Iinuma
- Department of Anatomy and Neuroscience, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Jun Yamada
- Department of Anatomy and Neuroscience, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Shozo Jinno
- Department of Anatomy and Neuroscience, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
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222
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Zhang S, Lachance BB, Mattson MP, Jia X. Glucose metabolic crosstalk and regulation in brain function and diseases. Prog Neurobiol 2021; 204:102089. [PMID: 34118354 DOI: 10.1016/j.pneurobio.2021.102089] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 04/08/2021] [Accepted: 06/01/2021] [Indexed: 01/11/2023]
Abstract
Brain glucose metabolism, including glycolysis, the pentose phosphate pathway, and glycogen turnover, produces ATP for energetic support and provides the precursors for the synthesis of biological macromolecules. Although glucose metabolism in neurons and astrocytes has been extensively studied, the glucose metabolism of microglia and oligodendrocytes, and their interactions with neurons and astrocytes, remain critical to understand brain function. Brain regions with heterogeneous cell composition and cell-type-specific profiles of glucose metabolism suggest that metabolic networks within the brain are complex. Signal transduction proteins including those in the Wnt, GSK-3β, PI3K-AKT, and AMPK pathways are involved in regulating these networks. Additionally, glycolytic enzymes and metabolites, such as hexokinase 2, acetyl-CoA, and enolase 2, are implicated in the modulation of cellular function, microglial activation, glycation, and acetylation of biomolecules. Given these extensive networks, glucose metabolism dysfunction in the whole brain or specific cell types is strongly associated with neurologic pathology including ischemic brain injury and neurodegenerative disorders. This review characterizes the glucose metabolism networks of the brain based on molecular signaling and cellular and regional interactions, and elucidates glucose metabolism-based mechanisms of neurological diseases and therapeutic approaches that may ameliorate metabolic abnormalities in those diseases.
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Affiliation(s)
- Shuai Zhang
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, MD, 21201, United States
| | - Brittany Bolduc Lachance
- Program in Trauma, Department of Neurology, University of Maryland School of Medicine, Baltimore, MD, 21201, United States
| | - Mark P Mattson
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, United States
| | - Xiaofeng Jia
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, MD, 21201, United States; Department of Orthopedics, University of Maryland School of Medicine, Baltimore, MD, 21201, United States; Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, 21201, United States; Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, United States; Department of Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, United States.
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223
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Zheng T, Zhang Z. Activated microglia facilitate the transmission of α-synuclein in Parkinson's disease. Neurochem Int 2021; 148:105094. [PMID: 34097990 DOI: 10.1016/j.neuint.2021.105094] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 05/23/2021] [Accepted: 05/31/2021] [Indexed: 01/31/2023]
Abstract
Parkinson's disease (PD) is characterized by the loss of dopaminergic neurons in the substantia nigra pars compacta and abnormal aggregates of α-synuclein protein called Lewy bodies. To date, there is no drug that can definitely slow down or stop the progression of this disease. The discovery of the cell-to-cell transmission of pathologic α-synuclein seeds offers the possibility to explore novel treatment strategies to prevent the spread of α-synuclein, with the purpose of slowing down the progression of PD in its tracks. Although recent studies have made tremendous progress in understanding how α-synuclein spreads throughout the brain, neuroinflammation seems to play a crucial role in the development of α-synuclein pathology in PD. The activation of microglia, one of the hallmarks of the neuroinflammatory process, is suggested to influence the neuron-to-neuron transmission of α-synuclein. This review summarizes how activated microglia facilitate this process, and focuses on the following mechanisms including the activation of microglia in PD, the reduced ability of activated microglia to clear α-synuclein and increased migratory capacity of microglia in PD, as well as the cooperation between microglia and exosomes in mediating α-synuclein release and propagation. In conclusion, this article help collate information on microglia in-relation to PD.
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Affiliation(s)
- Tingting Zheng
- Department of Neurology, The First Affiliated Hospital of Zhejiang Chinese Medical University (Zhejiang Provincial Hospital of Traditional Chinese Medicine), 54 Youdian Road, Hangzhou 310006, China
| | - Zhengxiang Zhang
- Department of Neurology, The First Affiliated Hospital of Zhejiang Chinese Medical University (Zhejiang Provincial Hospital of Traditional Chinese Medicine), 54 Youdian Road, Hangzhou 310006, China.
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Campos RM, Barbosa-Silva MC, Ribeiro-Resende VT. Comparison of effect of crush or transection peripheral nerve lesion on lumbar spinal cord synaptic plasticity and microglial dynamics. IBRO Neurosci Rep 2021; 10:225-235. [PMID: 34179871 PMCID: PMC8211924 DOI: 10.1016/j.ibneur.2021.05.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 05/10/2021] [Accepted: 05/12/2021] [Indexed: 11/22/2022] Open
Abstract
In an injury to the peripheral nervous system, the spinal cord and brain structure reorganize connections to optimize the function of the remaining parts. Many cell events are triggered in the spinal cord to support changes in the synaptic connections around motoneurons, where old connections are removed, and new ones created. Microglial cells are primitive macrophages that invade the central nervous system in early stages of neurodevelopment and have several functions, such as eliminating synapses. We investigated the synaptic plasticity after different types of peripheral (sciatic) nerve injury (crush or total transection), as well as the behavior of microglial cells for 2 weeks after a peripheral lesion. As expected, sciatic-nerve injury reduced motor performance in mice, but crushed animals regained partial motor control. Because of sciatic-nerve injury, pre-synaptic inputs decreased around the motoneurons in the ventro-lateral horn, while microglial cells increased around these cells. Microglial cells also exhibited altered morphology in both types of peripheral lesion, indicating a similar underlying mechanism of plasticity. To investigate the involvement of microglia in this scenario, microglial activation was modulated by daily administration of minocycline. The minocycline treatment directly affected the microglial response and impacted the synapse rearrangement in the spinal cord. Together, these results demonstrate that microglia cells are involved in synaptic plasticity in the lumbar spinal cord in both nerve-injury scenarios. SUMMARY OF STATEMENT Here, we demonstrated that acute plasticity in the lumbar spinal cord (LSC) did not differ between crush and transection of peripheral nerve, and that microglial reactivity in the LSC was important after both injury types.
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Affiliation(s)
- Raquel M.P. Campos
- Instituto de Biofísica Carlos Chagas Filho, Laboratório de Neuroquímica, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil
| | - Maria Carolina Barbosa-Silva
- Instituto de Biofísica Carlos Chagas Filho, Laboratório de Neuroquímica, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil
| | - Victor T. Ribeiro-Resende
- Instituto de Biofísica Carlos Chagas Filho, Laboratório de Neuroquímica, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil
- Núcleo Multidisciplinar de Pesquisa em Biologia (Numpex-Bio), Campus de Duque de Caxias Geraldo Guerra Cidade, Universidade Federal do Rio de Janeiro, Duque de Caxias, RJ 25255-030, Brazil
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225
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McGregor BA, Schommer J, Guo K, Raihan MO, Ghribi O, Hur J, Porter JE. Alpha-Synuclein-induced DNA Methylation and Gene Expression in Microglia. Neuroscience 2021; 468:186-198. [PMID: 34082066 DOI: 10.1016/j.neuroscience.2021.05.027] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 05/21/2021] [Accepted: 05/24/2021] [Indexed: 12/18/2022]
Abstract
Synucleinopathy disorders are characterized by aggregates of α-synuclein (α-syn), which engage microglia to elicit a neuroinflammatory response. Here, we determined the gene expression and DNA methylation changes in microglia induced by aggregate α-syn. Transgenic murine Thy-1 promoter (mThy1)-Asyn mice overexpressing human α-syn are a model of synucleinopathy. Microglia from 3 and 13-month-old mice were used to isolate nucleic acids for methylated DNA and RNA-sequencing. α-Syn-regulated changes in gene expression and genomic methylation were determined and examined for functional enrichment followed by network analysis to further elucidate possible connections within the data. Microglial DNA isolated from our 3-month cohort had 5315 differentially methylated gene (DMG) changes, while RNA levels demonstrated a change in 119 differentially expressed genes (DEGs) between mThy1-Asyn mice and wild-type littermate controls. The 3-month DEGs and DMGs were highly associated with adhesion and migration signaling, suggesting a phenotypic transition from resting to active microglia. We observed 3742 DMGs and 3766 DEGs in 13-month mThy1-Asyn mice. These genes were often related to adhesion, migration, cell cycle, cellular metabolism, and immune response. Network analysis also showed increased cell mobility and inflammatory functions at 3 months, shifting to cell cycle, immune response, and metabolism changes at 13 months. We observed significant α-syn-induced methylation and gene expression changes in microglia. Our data suggest that α-syn overexpression initiates microglial activation leading to neuroinflammation and cellular metabolic stresses, which is associated with disease progression.
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Affiliation(s)
- Brett A McGregor
- Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks, ND 58202, USA
| | - Jared Schommer
- Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks, ND 58202, USA
| | - Kai Guo
- Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks, ND 58202, USA
| | - Md Obayed Raihan
- Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks, ND 58202, USA
| | - Othman Ghribi
- Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks, ND 58202, USA
| | - Junguk Hur
- Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks, ND 58202, USA.
| | - James E Porter
- Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, Grand Forks, ND 58202, USA.
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226
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Lee E, Eo JC, Lee C, Yu JW. Distinct Features of Brain-Resident Macrophages: Microglia and Non-Parenchymal Brain Macrophages. Mol Cells 2021; 44:281-291. [PMID: 33972475 PMCID: PMC8175151 DOI: 10.14348/molcells.2021.0060] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 04/12/2021] [Accepted: 04/12/2021] [Indexed: 12/11/2022] Open
Abstract
Tissue-resident macrophages play an important role in maintaining tissue homeostasis and innate immune defense against invading microbial pathogens. Brain-resident macrophages can be classified into microglia in the brain parenchyma and non-parenchymal brain macrophages, also known as central nervous system-associated or border-associated macrophages, in the brain-circulation interface. Microglia and non-parenchymal brain macrophages, including meningeal, perivascular, and choroid plexus macrophages, are mostly produced during embryonic development, and maintained their population by self-renewal. Microglia have gained much attention for their dual roles in the maintenance of brain homeostasis and the induction of neuroinflammation. In particular, diverse phenotypes of microglia have been increasingly identified under pathological conditions. Single-cell phenotypic analysis revealed that microglia are highly heterogenous and plastic, thus it is difficult to define the status of microglia as M1/M2 or resting/activated state due to complex nature of microglia. Meanwhile, physiological function of non-parenchymal brain macrophages remain to be fully demonstrated. In this review, we have summarized the origin and signatures of brain-resident macrophages and discussed the unique features of microglia, particularly, their phenotypic polarization, diversity of subtypes, and inflammasome responses related to neurodegenerative diseases.
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Affiliation(s)
- Eunju Lee
- Department of Microbiology and Immunology, Institute for Immunology and Immunological Diseases, Brain Korea 21 Project for Medical Science, Yonsei University College of Medicine, Seoul 03722, Korea
| | - Jun-Cheol Eo
- Department of Microbiology and Immunology, Institute for Immunology and Immunological Diseases, Brain Korea 21 Project for Medical Science, Yonsei University College of Medicine, Seoul 03722, Korea
| | - Changjun Lee
- Department of Microbiology and Immunology, Institute for Immunology and Immunological Diseases, Brain Korea 21 Project for Medical Science, Yonsei University College of Medicine, Seoul 03722, Korea
| | - Je-Wook Yu
- Department of Microbiology and Immunology, Institute for Immunology and Immunological Diseases, Brain Korea 21 Project for Medical Science, Yonsei University College of Medicine, Seoul 03722, Korea
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227
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Guo M, Hao Y, Feng Y, Li H, Mao Y, Dong Q, Cui M. Microglial Exosomes in Neurodegenerative Disease. Front Mol Neurosci 2021; 14:630808. [PMID: 34045943 PMCID: PMC8148341 DOI: 10.3389/fnmol.2021.630808] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 04/09/2021] [Indexed: 12/20/2022] Open
Abstract
Microglia play an important role in neurodegenerative disease [i.e., Parkinson's disease (PD), Alzheimer's disease (AD), and amyotrophic lateral sclerosis (ALS)]. These diseases share some similar pathological changes and several microglia-associated processes, including immune response, neuroinflammation, phagocytosis, elimination of synapses et al. Microglia in the central nervous system (CNS) has been described as having both destructive and protective effects in neurological disorders. Besides, considerable evidence also indicates that microglia play a significant role in neurogenesis, neuronal cell death, and synaptic interactions. The communication between microglia and neurons is of vital role in regulating complex functions which are key to appropriate the activity of the brain. Accumulating studies have also demonstrated that exosomes with sizes ranging from 40-100 nm, released by microglia, could serve as key mediators in intercellular signaling. These exosomes, identified in terms of cellular origin in many kinds of biological fluids, exert their effects by delivering specific cargos such as proteins, microRNAs (miRNAs), and mRNAs. It was shown that microglial exosomes could transport to and be uptake by neurons, which may either be beneficial or instead, detrimental to CNS diseases. The focus of this review is to summarize the involvement of microglial exosomes in critical pathologies associated with neurodegenerative disease and how they contribute to these disorders, including PD, AD, and ALS. We also review the application of microglia exosomes as potential biomarkers in monitoring disease progression, as well as focusing on their roles as drug delivery vehicles in treating neurodegenerative disorders.
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Affiliation(s)
- Min Guo
- Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China
| | - Yining Hao
- Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China
| | - Yiwei Feng
- Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China
| | - Haiqing Li
- Department of Radiology, Huashan Hospital, Fudan University, Shanghai, China
| | - Yiting Mao
- Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China
| | - Qiang Dong
- Department of Neurology, Huashan Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Fudan University, Shanghai, China
| | - Mei Cui
- Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China
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228
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Candlish M, Hefendehl JK. Microglia Phenotypes Converge in Aging and Neurodegenerative Disease. Front Neurol 2021; 12:660720. [PMID: 34025562 PMCID: PMC8133315 DOI: 10.3389/fneur.2021.660720] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 03/19/2021] [Indexed: 01/22/2023] Open
Abstract
Microglia, the primary immune cells of the central nervous system, hold a multitude of tasks in order to ensure brain homeostasis and are one of the best predictors of biological age on a cellular level. We and others have shown that these long-lived cells undergo an aging process that impedes their ability to perform some of the most vital homeostatic functions such as immune surveillance, acute injury response, and clearance of debris. Microglia have been described as gradually transitioning from a homeostatic state to an activated state in response to various insults, as well as aging. However, microglia show diverse responses to presented stimuli in the form of acute injury or chronic disease. This complexity is potentially further compounded by the distinct alterations that globally occur in the aging process. In this review, we discuss factors that may contribute to microglial aging, as well as transcriptional microglia alterations that occur in old age. We then compare these distinct phenotypic changes with microglial phenotype in neurodegenerative disease.
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Affiliation(s)
- Michael Candlish
- Institute of Cell Biology and Neuroscience, Buchmann Institute for Molecular Life Sciences, Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Jasmin K Hefendehl
- Institute of Cell Biology and Neuroscience, Buchmann Institute for Molecular Life Sciences, Goethe University Frankfurt, Frankfurt am Main, Germany
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229
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Aichholzer F, Klafki HW, Ogorek I, Vogelgsang J, Wiltfang J, Scherbaum N, Weggen S, Wirths O. Evaluation of cerebrospinal fluid glycoprotein NMB (GPNMB) as a potential biomarker for Alzheimer's disease. ALZHEIMERS RESEARCH & THERAPY 2021; 13:94. [PMID: 33947460 PMCID: PMC8097817 DOI: 10.1186/s13195-021-00828-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Accepted: 04/12/2021] [Indexed: 01/01/2023]
Abstract
Background Alzheimer’s disease (AD) is a neurodegenerative disorder associated with extracellular amyloid-β peptide deposition and progressive neuron loss. Strong evidence supports that neuroinflammatory changes such as the activation of astrocytes and microglia cells are important in the disease process. Glycoprotein nonmetastatic melanoma protein B (GPNMB) is a transmembrane glycoprotein that has recently been associated with an emerging role in neuroinflammation, which has been reported to be increased in post-mortem brain samples from AD and Parkinson’s disease patients. Methods The present study describes the partial “fit for purpose” validation of a commercially available immunoassay for the determination of GPNMB levels in the cerebrospinal fluid (CSF). We further assessed the applicability of GPNMB as a potential biomarker for AD in two different cohorts that were defined by biomarker-supported clinical diagnosis or by neuroimaging with amyloid positron emission tomography, respectively. Results The results indicated that CSF GPNMB levels could not distinguish between AD or controls with other neurological diseases but correlated with other parameters such as aging and CSF pTau levels. Conclusions The findings of this study do not support GPNMB in CSF as a valuable neurochemical diagnostic biomarker of AD but warrant further studies employing healthy control individuals. Supplementary Information The online version contains supplementary material available at 10.1186/s13195-021-00828-1.
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Affiliation(s)
- Freyja Aichholzer
- Department of Psychiatry and Psychotherapy, University Medical Center (UMG), Georg-August-University, Von-Siebold-Str. 5, 37075, Göttingen, Germany
| | - Hans-Wolfgang Klafki
- Department of Psychiatry and Psychotherapy, University Medical Center (UMG), Georg-August-University, Von-Siebold-Str. 5, 37075, Göttingen, Germany
| | - Isabella Ogorek
- Department of Neuropathology, Heinrich-Heine-University, Düsseldorf, Germany
| | - Jonathan Vogelgsang
- Department of Psychiatry and Psychotherapy, University Medical Center (UMG), Georg-August-University, Von-Siebold-Str. 5, 37075, Göttingen, Germany
| | - Jens Wiltfang
- Department of Psychiatry and Psychotherapy, University Medical Center (UMG), Georg-August-University, Von-Siebold-Str. 5, 37075, Göttingen, Germany.,Neurosciences and Signaling Group, Department of Medical Sciences, Institute of Biomedicine (ibiMED), University of Aveiro, Aveiro, Portugal.,German Center for Neurodegenerative Diseases (DZNE), Göttingen, Germany
| | - Norbert Scherbaum
- LVR-Hospital Essen, Department of Psychiatry and Psychotherapy, Medical Faculty, University of Duisburg-Essen, Essen, Germany
| | - Sascha Weggen
- Department of Neuropathology, Heinrich-Heine-University, Düsseldorf, Germany
| | - Oliver Wirths
- Department of Psychiatry and Psychotherapy, University Medical Center (UMG), Georg-August-University, Von-Siebold-Str. 5, 37075, Göttingen, Germany.
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230
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Sun N, Meng X, Liu Y, Song D, Jiang C, Cai J. Applications of brain organoids in neurodevelopment and neurological diseases. J Biomed Sci 2021; 28:30. [PMID: 33888112 PMCID: PMC8063318 DOI: 10.1186/s12929-021-00728-4] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Accepted: 04/18/2021] [Indexed: 12/20/2022] Open
Abstract
A brain organoid is a self-organizing three-dimensional tissue derived from human embryonic stem cells or pluripotent stem cells and is able to simulate the architecture and functionality of the human brain. Brain organoid generation methods are abundant and continue to improve, and now, an in vivo vascularized brain organoid has been encouragingly reported. The combination of brain organoids with immune-staining and single-cell sequencing technology facilitates our understanding of brain organoids, including the structural organization and the diversity of cell types. Recent publications have reported that brain organoids can mimic the dynamic spatiotemporal process of early brain development, model various human brain disorders, and serve as an effective preclinical platform to test and guide personalized treatment. In this review, we introduce the current state of brain organoid differentiation strategies, summarize current progress and applications in the medical domain, and discuss the challenges and prospects of this promising technology.
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Affiliation(s)
- Nan Sun
- Department of Neurosurgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, 150086, China
| | - Xiangqi Meng
- Department of Neurosurgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, 150086, China
| | - Yuxiang Liu
- Department of Neurosurgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, 150086, China
| | - Dan Song
- Department of Neurosurgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, 150086, China
| | - Chuanlu Jiang
- Department of Neurosurgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, 150086, China.
| | - Jinquan Cai
- Department of Neurosurgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, 150086, China.
- Department of Microbiology, Tumor and Cell Biology (MTC), Biomedicum, Karolinska Institutet, 171 65, Stockholm, Sweden.
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231
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Microglial heterogeneity in aging and Alzheimer's disease: Is sex relevant? J Pharmacol Sci 2021; 146:169-181. [PMID: 34030799 DOI: 10.1016/j.jphs.2021.03.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 02/24/2021] [Accepted: 03/22/2021] [Indexed: 02/08/2023] Open
Abstract
Neurodegenerative diseases and their associated cognitive decline are known to be more prevalent during aging. Recent evidence has uncovered the role of microglia, the immunocompetent cells of the brain, in dysfunctions linked to neurodegenerative diseases such as is Alzheimer's disease (AD). Similar to other pathologies, AD is shown to be sex-biased, with females being more at risk compared to males. While the mechanisms driving this prevalence are still unclear, emerging data suggest the sex differences present in microglia throughout life might lead to different responses of these cells in both health and disease. Furthermore, microglial cells have recently been recognized as a deeply heterogeneous population, with multiple subsets and/or phenotypes stemming from diverse parameters such as age, sex or state of health. Therefore, this review discusses microglial heterogeneity during aging in both basal conditions and AD with a focus on existing sex differences in this process.
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232
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Bouadi O, Tay TL. More Than Cell Markers: Understanding Heterogeneous Glial Responses to Implantable Neural Devices. Front Cell Neurosci 2021; 15:658992. [PMID: 33912015 PMCID: PMC8071943 DOI: 10.3389/fncel.2021.658992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 03/17/2021] [Indexed: 11/30/2022] Open
Affiliation(s)
- Ouzéna Bouadi
- Faculty of Biology, University of Freiburg, Freiburg, Germany.,Faculty of Life Sciences, University of Strasbourg, Strasbourg, France
| | - Tuan Leng Tay
- Faculty of Biology, University of Freiburg, Freiburg, Germany.,BrainLinks-BrainTools Centre, University of Freiburg, Freiburg, Germany.,Freiburg Institute of Advanced Studies, University of Freiburg, Freiburg, Germany
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233
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Lim D, Semyanov A, Genazzani A, Verkhratsky A. Calcium signaling in neuroglia. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2021; 362:1-53. [PMID: 34253292 DOI: 10.1016/bs.ircmb.2021.01.003] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Glial cells exploit calcium (Ca2+) signals to perceive the information about the activity of the nervous tissue and the tissue environment to translate this information into an array of homeostatic, signaling and defensive reactions. Astrocytes, the best studied glial cells, use several Ca2+ signaling generation pathways that include Ca2+ entry through plasma membrane, release from endoplasmic reticulum (ER) and from mitochondria. Activation of metabotropic receptors on the plasma membrane of glial cells is coupled to an enzymatic cascade in which a second messenger, InsP3 is generated thus activating intracellular Ca2+ release channels in the ER endomembrane. Astrocytes also possess store-operated Ca2+ entry and express several ligand-gated Ca2+ channels. In vivo astrocytes generate heterogeneous Ca2+ signals, which are short and frequent in distal processes, but large and relatively rare in soma. In response to neuronal activity intracellular and inter-cellular astrocytic Ca2+ waves can be produced. Astrocytic Ca2+ signals are involved in secretion, they regulate ion transport across cell membranes, and are contributing to cell morphological plasticity. Therefore, astrocytic Ca2+ signals are linked to fundamental functions of the central nervous system ranging from synaptic transmission to behavior. In oligodendrocytes, Ca2+ signals are generated by plasmalemmal Ca2+ influx, or by release from intracellular stores, or by combination of both. Microglial cells exploit Ca2+ permeable ionotropic purinergic receptors and transient receptor potential channels as well as ER Ca2+ release. In this contribution, basic morphology of glial cells, glial Ca2+ signaling toolkit, intracellular Ca2+ signals and Ca2+-regulated functions are discussed with focus on astrocytes.
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Affiliation(s)
- Dmitry Lim
- Department of Pharmaceutical Sciences, Università del Piemonte Orientale, Novara, Italy.
| | - Alexey Semyanov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia; Faculty of Biology, Moscow State University, Moscow, Russia; Sechenov First Moscow State Medical University, Moscow, Russia
| | - Armando Genazzani
- Department of Pharmaceutical Sciences, Università del Piemonte Orientale, Novara, Italy
| | - Alexei Verkhratsky
- Sechenov First Moscow State Medical University, Moscow, Russia; Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, United Kingdom; Achucarro Centre for Neuroscience, IKERBASQUE, Basque Foundation for Science, Bilbao, Spain.
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234
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Keane L, Cheray M, Blomgren K, Joseph B. Multifaceted microglia - key players in primary brain tumour heterogeneity. Nat Rev Neurol 2021; 17:243-259. [PMID: 33692572 DOI: 10.1038/s41582-021-00463-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/20/2021] [Indexed: 01/31/2023]
Abstract
Microglia are the resident innate immune cells of the immune-privileged CNS and, as such, represent the first line of defence against tissue injury and infection. Given their location, microglia are undoubtedly the first immune cells to encounter a developing primary brain tumour. Our knowledge of these cells is therefore important to consider in the context of such neoplasms. As the heterogeneous nature of the most aggressive primary brain tumours is thought to underlie their poor prognosis, this Review places a special emphasis on the heterogeneity of the tumour-associated microglia and macrophage populations present in primary brain tumours. Where available, specific information on microglial heterogeneity in various types and subtypes of brain tumour is included. Emerging evidence that highlights the importance of considering the heterogeneity of both the tumour and of microglial populations in providing improved treatment outcomes for patients is also discussed.
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Affiliation(s)
- Lily Keane
- Institute of Environmental Medicine, Toxicology Unit, Karolinska Institutet, Stockholm, Sweden
| | - Mathilde Cheray
- Institute of Environmental Medicine, Toxicology Unit, Karolinska Institutet, Stockholm, Sweden
| | - Klas Blomgren
- Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden.,Department of Paediatric Oncology, Karolinska University Hospital, Stockholm, Sweden
| | - Bertrand Joseph
- Institute of Environmental Medicine, Toxicology Unit, Karolinska Institutet, Stockholm, Sweden.
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235
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Uriarte Huarte O, Richart L, Mittelbronn M, Michelucci A. Microglia in Health and Disease: The Strength to Be Diverse and Reactive. Front Cell Neurosci 2021; 15:660523. [PMID: 33867943 PMCID: PMC8044310 DOI: 10.3389/fncel.2021.660523] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 03/15/2021] [Indexed: 12/11/2022] Open
Abstract
Microglia are the resident immune effector cells of the central nervous system (CNS) rapidly reacting to any perturbation in order to maintain CNS homeostasis. Although their outstanding reactive properties have been elucidated over the last decades, their heterogeneity in healthy tissue, such as across brain regions, as well as their diversity in the development and progression of brain diseases, are currently opening new avenues to understand the cellular and functional states of microglia subsets in a context-dependent manner. Here, we review the main breakthrough studies that helped in elucidating microglia heterogeneity in the healthy and diseased brain and might pave the way to critical functional screenings of the inferred cellular diversity. We suggest that unraveling the cellular and molecular mechanisms underlying specific functionalities of microglial subpopulations, which may ultimately support or harm the neuronal network in neurodegenerative diseases, or may acquire pro- or anti-tumorigenic phenotypes in brain tumors, will possibly uncover new therapeutic avenues for to date non-curable neurological disorders.
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Affiliation(s)
- Oihane Uriarte Huarte
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Esch-sur-Alzette, Luxembourg.,Luxembourg Center of Neuropathology, Luxembourg, Luxembourg
| | - Lorraine Richart
- Luxembourg Center of Neuropathology, Luxembourg, Luxembourg.,Department of Oncology (DONC), Luxembourg Institute of Health (LIH), Luxembourg, Luxembourg.,Faculty of Science, Technology and Medicine, University of Luxembourg, Belvaux, Luxembourg
| | - Michel Mittelbronn
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Esch-sur-Alzette, Luxembourg.,Luxembourg Center of Neuropathology, Luxembourg, Luxembourg.,Department of Oncology (DONC), Luxembourg Institute of Health (LIH), Luxembourg, Luxembourg.,National Center of Pathology (NCP), Laboratoire National de Santé (LNS), Dudelange, Luxembourg
| | - Alessandro Michelucci
- Neuro-Immunology Group, Department of Oncology (DONC), Luxembourg Institute of Health (LIH), Luxembourg, Luxembourg
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236
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Uriarte Huarte O, Kyriakis D, Heurtaux T, Pires-Afonso Y, Grzyb K, Halder R, Buttini M, Skupin A, Mittelbronn M, Michelucci A. Single-Cell Transcriptomics and In Situ Morphological Analyses Reveal Microglia Heterogeneity Across the Nigrostriatal Pathway. Front Immunol 2021; 12:639613. [PMID: 33854507 PMCID: PMC8039119 DOI: 10.3389/fimmu.2021.639613] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 03/11/2021] [Indexed: 12/14/2022] Open
Abstract
Microglia are the resident immune effector cells of the central nervous system (CNS) rapidly reacting to various pathological stimuli to maintain CNS homeostasis. However, microglial reactions in the CNS may also worsen neurological disorders. Hence, the phenotypic analysis of microglia in healthy tissue may identify specific poised subsets ultimately supporting or harming the neuronal network. This is all the more important for the understanding of CNS disorders exhibiting regional-specific and cellular pathological hallmarks, such as many neurodegenerative disorders, including Parkinson's disease (PD). In this context, we aimed to address the heterogeneity of microglial cells in susceptible brain regions for PD, such as the nigrostriatal pathway. Here, we combined single-cell RNA-sequencing with immunofluorescence analyses of the murine nigrostriatal pathway, the most affected brain region in PD. We uncovered a microglia subset, mainly present in the midbrain, displaying an intrinsic transcriptional immune alerted signature sharing features of inflammation-induced microglia. Further, an in situ morphological screening of inferred cellular diversity showed a decreased microglia complexity in the midbrain when compared to striatum. Our study provides a resource for the identification of specific microglia phenotypes within the nigrostriatal pathway, which may be relevant in PD.
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Affiliation(s)
- Oihane Uriarte Huarte
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Esch-sur-Alzette, Luxembourg.,Luxembourg Center of Neuropathology (LCNP), Luxembourg, Luxembourg
| | - Dimitrios Kyriakis
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Tony Heurtaux
- Luxembourg Center of Neuropathology (LCNP), Luxembourg, Luxembourg.,Department of Life Sciences and Medicine (DLSM), University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Yolanda Pires-Afonso
- Neuro-Immunology Group, Department of Oncology (DONC), Luxembourg Institute of Health (LIH), Luxembourg, Luxembourg.,Faculty of Science, Technology and Medicine, University of Luxembourg, Belvaux, Luxembourg
| | - Kamil Grzyb
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Rashi Halder
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Manuel Buttini
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Esch-sur-Alzette, Luxembourg.,Luxembourg Center of Neuropathology (LCNP), Luxembourg, Luxembourg
| | - Alexander Skupin
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Esch-sur-Alzette, Luxembourg.,National Center for Microscopy and Imaging Research, University of California San Diego, La Jolla, CA, United States
| | - Michel Mittelbronn
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Esch-sur-Alzette, Luxembourg.,Luxembourg Center of Neuropathology (LCNP), Luxembourg, Luxembourg.,Department of Oncology (DONC), Luxembourg Institute of Health (LIH), Luxembourg, Luxembourg.,National Center of Pathology (NCP), Laboratoire National de Santé (LNS), Dudelange, Luxembourg
| | - Alessandro Michelucci
- Luxembourg Centre for Systems Biomedicine (LCSB), University of Luxembourg, Esch-sur-Alzette, Luxembourg.,Neuro-Immunology Group, Department of Oncology (DONC), Luxembourg Institute of Health (LIH), Luxembourg, Luxembourg
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237
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Afridi R, Seol S, Kang HJ, Suk K. Brain-immune interactions in neuropsychiatric disorders: Lessons from transcriptome studies for molecular targeting. Biochem Pharmacol 2021; 188:114532. [PMID: 33773976 DOI: 10.1016/j.bcp.2021.114532] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 03/18/2021] [Accepted: 03/18/2021] [Indexed: 12/12/2022]
Abstract
Understanding the pathophysiological mechanisms of neuropsychiatric disorders has been a challenging quest for neurobiologists. Recent years have witnessed enormous technological advances in the field of neuroimmunology, blurring boundaries between the central nervous system and the periphery. Consequently, the discipline has expanded to cover interactions between the nervous and immune systems in health and diseases. The complex interplay between the peripheral and central immune pathways in neuropsychiatric disorders has recently been documented in various studies, but the genetic determinants remain elusive. Recent transcriptome studies have identified dysregulated genes involved in peripheral immune cell activation, blood-brain barrier integrity, glial cell activation, and synaptic plasticity in major depressive disorder, bipolar disorder, autism spectrum disorder, and schizophrenia. Herein, the key transcriptomic techniques applied in investigating differentially expressed genes and pathways responsible for altered brain-immune interactions in neuropsychiatric disorders are discussed. The application of transcriptomics that can aid in identifying molecular targets in various neuropsychiatric disorders is highlighted.
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Affiliation(s)
- Ruqayya Afridi
- Department of Pharmacology, Brain Science & Engineering Institute, BK21 Plus KNU Biomedical Convergence Program, School of Medicine, Kyungpook National University, Daegu, Republic of Korea
| | - Sihwan Seol
- Department of Life Science, Chung-Ang University, Seoul, Republic of Korea
| | - Hyo Jung Kang
- Department of Life Science, Chung-Ang University, Seoul, Republic of Korea.
| | - Kyoungho Suk
- Department of Pharmacology, Brain Science & Engineering Institute, BK21 Plus KNU Biomedical Convergence Program, School of Medicine, Kyungpook National University, Daegu, Republic of Korea.
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238
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Chowen JA, Garcia-Segura LM. Role of glial cells in the generation of sex differences in neurodegenerative diseases and brain aging. Mech Ageing Dev 2021; 196:111473. [PMID: 33766745 DOI: 10.1016/j.mad.2021.111473] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 03/14/2021] [Accepted: 03/16/2021] [Indexed: 12/11/2022]
Abstract
Diseases and aging-associated alterations of the nervous system often show sex-specific characteristics. Glial cells play a major role in the endogenous homeostatic response of neural tissue, and sex differences in the glial transcriptome and function have been described. Therefore, the possible role of these cells in the generation of sex differences in pathological alterations of the nervous system is reviewed here. Studies have shown that glia react to pathological insults with sex-specific neuroprotective and regenerative effects. At least three factors determine this sex-specific response of glia: sex chromosome genes, gonadal hormones and neuroactive steroid hormone metabolites. The sex chromosome complement determines differences in the transcriptional responses in glia after brain injury, while gonadal hormones and their metabolites activate sex-specific neuroprotective mechanisms in these cells. Since the sex-specific neuroprotective and regenerative activity of glial cells causes sex differences in the pathological alterations of the nervous system, glia may represent a relevant target for sex-specific therapeutic interventions.
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Affiliation(s)
- Julie A Chowen
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación la Princesa, Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y Nutriciόn (CIBEROBN), Instituto de Salud Carlos III, and IMDEA Food Institute, CEIUAM+CSIC, Madrid, Spain.
| | - Luis M Garcia-Segura
- Instituto Cajal, Consejo Superior de Investigaciones Científicas (CSIC) and Centro de Investigación Biomédica en Red de Fragilidad y Envejecimiento Saludable (CIBERFES), Instituto de Salud Carlos III, Madrid, Spain.
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239
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Microglial Heterogeneity and Its Potential Role in Driving Phenotypic Diversity of Alzheimer's Disease. Int J Mol Sci 2021; 22:ijms22052780. [PMID: 33803478 PMCID: PMC7967159 DOI: 10.3390/ijms22052780] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 03/04/2021] [Accepted: 03/05/2021] [Indexed: 01/03/2023] Open
Abstract
Alzheimer’s disease (AD) is increasingly recognized as a highly heterogeneous disorder occurring under distinct clinical and neuropathological phenotypes. Despite the molecular determinants of such variability not being well defined yet, microglial cells may play a key role in this process by releasing distinct pro- and/or anti-inflammatory cytokines, potentially affecting the expression of the disease. We carried out a neuropathological and biochemical analysis on a series of AD brain samples, gathering evidence about the heterogeneous involvement of microglia in AD. The neuropathological studies showed differences concerning morphology, density and distribution of microglial cells among AD brains. Biochemical investigations showed increased brain levels of IL-4, IL-6, IL-13, CCL17, MMP-7 and CXCL13 in AD in comparison with control subjects. The molecular profiling achieved by measuring the brain levels of 25 inflammatory factors known to be involved in neuroinflammation allowed a stratification of the AD patients in three distinct “neuroinflammatory clusters”. These findings strengthen the relevance of neuroinflammation in AD pathogenesis suggesting, in particular, that the differential involvement of neuroinflammatory molecules released by microglial cells during the development of the disease may contribute to modulate the characteristics and the severity of the neuropathological changes, driving—at least in part—the AD phenotypic diversity.
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240
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Lyu J, Xie D, Bhatia TN, Leak RK, Hu X, Jiang X. Microglial/Macrophage polarization and function in brain injury and repair after stroke. CNS Neurosci Ther 2021; 27:515-527. [PMID: 33650313 PMCID: PMC8025652 DOI: 10.1111/cns.13620] [Citation(s) in RCA: 85] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 01/17/2021] [Accepted: 01/18/2021] [Indexed: 12/12/2022] Open
Abstract
Stroke is a leading cause of disability and mortality, with limited treatment options. After stroke injury, microglia and CNS‐resident macrophages are rapidly activated and regulate neuropathological processes to steer the course of functional recovery. To accelerate this recovery, microglia can engulf dying cells and clear irreparably‐damaged tissues, thereby creating a microenvironment that is more suitable for the formation of new neural circuitry. In addition, monocyte‐derived macrophages cross the compromised blood‐brain barrier to infiltrate the injured brain. The specific functions of myeloid lineage cells in brain injury and repair are diverse and dependent on phenotypic polarization statuses. However, it remains to be determined to what degree the CNS‐invading macrophages occupy different functional niches from CNS‐resident microglia. In this review, we describe the physiological characteristics and functions of microglia in the developing and adult brain. We also review (a) the activation and phenotypic polarization of microglia and macrophages after stroke, (b) molecular mechanisms that control polarization status, and (c) the contribution of microglia to brain pathology versus repair. Finally, we summarize current breakthroughs in therapeutic strategies that calibrate microglia/macrophage responses after stroke. The present review summarizes recent advances in microglial research in relation to stroke with emphases on microglial/macrophage phenotypic polarization and function in brain injury and repair. It also reviews the physiological characteristics and functions of microglia in the developing and adult brain, and describes current breakthroughs in therapeutic strategies that calibrate microglia/macrophage responses after stroke.
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Affiliation(s)
- Junxuan Lyu
- Department of Neurology, Pittsburgh Institute of Brain Disorders & Recovery, University of Pittsburgh, Pittsburgh, PA, USA
| | - Di Xie
- Department of Neurology, Pittsburgh Institute of Brain Disorders & Recovery, University of Pittsburgh, Pittsburgh, PA, USA
| | - Tarun N Bhatia
- Graduate School of Pharmaceutical Sciences, School of Pharmacy, Duquesne University, Pittsburgh, PA, USA
| | - Rehana K Leak
- Graduate School of Pharmaceutical Sciences, School of Pharmacy, Duquesne University, Pittsburgh, PA, USA
| | - Xiaoming Hu
- Department of Neurology, Pittsburgh Institute of Brain Disorders & Recovery, University of Pittsburgh, Pittsburgh, PA, USA.,Geriatric Research, Education and Clinical Center, Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA, USA
| | - Xiaoyan Jiang
- Department of Neurology, Pittsburgh Institute of Brain Disorders & Recovery, University of Pittsburgh, Pittsburgh, PA, USA.,Geriatric Research, Education and Clinical Center, Veterans Affairs Pittsburgh Health Care System, Pittsburgh, PA, USA
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241
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Hypothalamic Microglial Heterogeneity and Signature under High Fat Diet-Induced Inflammation. Int J Mol Sci 2021; 22:ijms22052256. [PMID: 33668314 PMCID: PMC7956484 DOI: 10.3390/ijms22052256] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 02/18/2021] [Accepted: 02/19/2021] [Indexed: 12/17/2022] Open
Abstract
Under high-fat feeding, the hypothalamus atypically undergoes pro-inflammatory signaling activation. Recent data from transcriptomic analysis of microglia from rodents and humans has allowed the identification of several microglial subpopulations throughout the brain. Numerous studies have clarified the roles of these cells in hypothalamic inflammation, but how each microglial subset plays its functions upon inflammatory stimuli remains unexplored. Fortunately, these data unveiling microglial heterogeneity have triggered the development of novel experimental models for studying the roles and characteristics of each microglial subtype. In this review, we explore microglial heterogeneity in the hypothalamus and their crosstalk with astrocytes under high fat diet-induced inflammation. We present novel currently available ex vivo and in vivo experimental models that can be useful when designing a new research project in this field of study. Last, we examine the transcriptomic data already published to identify how the hypothalamic microglial signature changes upon short-term and prolonged high-fat feeding.
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242
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Matos MC, Pinheiro A, Melo-Ferreira J, Davis RS, Esteves PJ. Evolution of Fc Receptor-Like Scavenger in Mammals. Front Immunol 2021; 11:590280. [PMID: 33708190 PMCID: PMC7940838 DOI: 10.3389/fimmu.2020.590280] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 12/31/2020] [Indexed: 11/13/2022] Open
Abstract
Fc receptor-like (FCRL) molecules comprise a large family of receptors, homologous to the receptors for the Fc portion of immunoglobulins (FCR). Within this family, an unusual gene known to exist in mice, rats and dogs, termed FCRLS, encodes a chimeric protein with both Ig-like FCRL and type B scavenger-receptor cysteine-rich (SRCR)-like domains. In mice, FCRLS is located next to the CD5L and KIRREL1 genes. Here, we show that the curious FCRLS gene is actually present across major mammalian groups, but its annotation is generally incorrect or absent. Anchored on mouse FCRLS and FCRL2 genomic sequence alignments, phylogenetic analyses demonstrated that many mammalian sequences currently annotated as FCRL2 cluster with FCRLS, supported by a conserved genetic synteny among organisms. This analysis shows that FCRLS is present in Rodentia, some Carnivora (Canidae and Ursidae), Chiroptera, Arctiodactyla, Proboscidae, and some Primata. Thus, the FCRLS most likely originated in a eutherian mammal ancestor since it is not present in Monotremata or Marsupialia. FCRLS has a peculiar distribution pattern across mammalian lineages, being present in some species, but absent in others from the same family, as in carnivores for example. The most parsimonious hypothesis to explain this FCRLS evolution is that it was convergently lost in several independent mammalian lineages. Analyses of branch-specific nucleotide evolutionary rates, show that FCRL2 and FCRLS have similar ranges of rates across mammals, suggesting that both genes have crucial, but separate functions in the immune system. Bayesian estimates of evolutionary rates for FCRLS in mammalian lineages revealed that carnivores display the highest mutation rate after rodents. Additionally, positive diversifying selection was detected for both FCRL2 and FCRLS. Our results show that the presence of the FCRLS gene is older and more widespread across mammals than previously thought and appears to be functional, being under positive selection. Its precise physiologic role should thus be investigated.
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Affiliation(s)
- Maria Carolina Matos
- Centro de Investigação em Biodiversidade e Recursos Genéticos (CIBIO-UP), Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO, Laboratório Associado, Universidade do Porto, Vairão, Portugal.,Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, Porto, Portugal
| | - Ana Pinheiro
- Centro de Investigação em Biodiversidade e Recursos Genéticos (CIBIO-UP), Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO, Laboratório Associado, Universidade do Porto, Vairão, Portugal
| | - José Melo-Ferreira
- Centro de Investigação em Biodiversidade e Recursos Genéticos (CIBIO-UP), Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO, Laboratório Associado, Universidade do Porto, Vairão, Portugal.,Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, Porto, Portugal
| | - Randall S Davis
- Departments of Medicine, Microbiology, and Biochemistry & Molecular Genetics and the Comprehensive Cancer Center, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Pedro José Esteves
- Centro de Investigação em Biodiversidade e Recursos Genéticos (CIBIO-UP), Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO, Laboratório Associado, Universidade do Porto, Vairão, Portugal.,Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, Porto, Portugal.,CITS - Centro de Investigação em Tecnologias de Saúde, Cooperativa de Ensino Superior Politécnico e Universitário, CRL (CESPU), Gandra, Portugal
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243
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Gonçalves de Andrade E, Šimončičová E, Carrier M, Vecchiarelli HA, Robert MÈ, Tremblay MÈ. Microglia Fighting for Neurological and Mental Health: On the Central Nervous System Frontline of COVID-19 Pandemic. Front Cell Neurosci 2021; 15:647378. [PMID: 33737867 PMCID: PMC7961561 DOI: 10.3389/fncel.2021.647378] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Accepted: 01/15/2021] [Indexed: 12/15/2022] Open
Abstract
Coronavirus disease 2019 (COVID-19) is marked by cardio-respiratory alterations, with increasing reports also indicating neurological and psychiatric symptoms in infected individuals. During COVID-19 pathology, the central nervous system (CNS) is possibly affected by direct severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) invasion, exaggerated systemic inflammatory responses, or hypoxia. Psychosocial stress imposed by the pandemic further affects the CNS of COVID-19 patients, but also the non-infected population, potentially contributing to the emergence or exacerbation of various neurological or mental health disorders. Microglia are central players of the CNS homeostasis maintenance and inflammatory response that exert their crucial functions in coordination with other CNS cells. During homeostatic challenges to the brain parenchyma, microglia modify their density, morphology, and molecular signature, resulting in the adjustment of their functions. In this review, we discuss how microglia may be involved in the neuroprotective and neurotoxic responses against CNS insults deriving from COVID-19. We examine how these responses may explain, at least partially, the neurological and psychiatric manifestations reported in COVID-19 patients and the general population. Furthermore, we consider how microglia might contribute to increased CNS vulnerability in certain groups, such as aged individuals and people with pre-existing conditions.
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Affiliation(s)
| | - Eva Šimončičová
- Division of Medical Science, University of Victoria, Victoria, BC, Canada
| | - Micaël Carrier
- Division of Medical Science, University of Victoria, Victoria, BC, Canada.,Axe Neurosciences, Centre de Recherche du CHU de Québec, Université de Laval, Québec City, QC, Canada
| | | | - Marie-Ève Robert
- Axe Neurosciences, Centre de Recherche du CHU de Québec, Université de Laval, Québec City, QC, Canada
| | - Marie-Ève Tremblay
- Division of Medical Science, University of Victoria, Victoria, BC, Canada.,Axe Neurosciences, Centre de Recherche du CHU de Québec, Université de Laval, Québec City, QC, Canada.,Neurology and Neurosurgery Department, McGill University, Montréal, QC, Canada.,Department of Molecular Medicine, Université de Laval, Québec City, QC, Canada.,Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC, Canada
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244
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Nahirney PC, Tremblay ME. Brain Ultrastructure: Putting the Pieces Together. Front Cell Dev Biol 2021; 9:629503. [PMID: 33681208 PMCID: PMC7930431 DOI: 10.3389/fcell.2021.629503] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2020] [Accepted: 01/20/2021] [Indexed: 12/11/2022] Open
Abstract
Unraveling the fine structure of the brain is important to provide a better understanding of its normal and abnormal functioning. Application of high-resolution electron microscopic techniques gives us an unprecedented opportunity to discern details of the brain parenchyma at nanoscale resolution, although identifying different cell types and their unique features in two-dimensional, or three-dimensional images, remains a challenge even to experts in the field. This article provides insights into how to identify the different cell types in the central nervous system, based on nuclear and cytoplasmic features, amongst other unique characteristics. From the basic distinction between neurons and their supporting cells, the glia, to differences in their subcellular compartments, organelles and their interactions, ultrastructural analyses can provide unique insights into the changes in brain function during aging and disease conditions, such as stroke, neurodegeneration, infection and trauma. Brain parenchyma is composed of a dense mixture of neuronal and glial cell bodies, together with their intertwined processes. Intracellular components that vary between cells, and can become altered with aging or disease, relate to the cytoplasmic and nucleoplasmic density, nuclear heterochromatin pattern, mitochondria, endoplasmic reticulum and Golgi complex, lysosomes, neurosecretory vesicles, and cytoskeletal elements (actin, intermediate filaments, and microtubules). Applying immunolabeling techniques to visualize membrane-bound or intracellular proteins in neurons and glial cells gives an even better appreciation of the subtle differences unique to these cells across contexts of health and disease. Together, our observations reveal how simple ultrastructural features can be used to identify specific changes in cell types, their health status, and functional relationships in the brain.
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Cellular Mechanisms Participating in Brain Repair of Adult Zebrafish and Mammals after Injury. Cells 2021; 10:cells10020391. [PMID: 33672842 PMCID: PMC7917790 DOI: 10.3390/cells10020391] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 01/28/2021] [Accepted: 02/05/2021] [Indexed: 12/12/2022] Open
Abstract
Adult neurogenesis is an evolutionary conserved process occurring in all vertebrates. However, striking differences are observed between the taxa, considering the number of neurogenic niches, the neural stem cell (NSC) identity, and brain plasticity under constitutive and injury-induced conditions. Zebrafish has become a popular model for the investigation of the molecular and cellular mechanisms involved in adult neurogenesis. Compared to mammals, the adult zebrafish displays a high number of neurogenic niches distributed throughout the brain. Furthermore, it exhibits a strong regenerative capacity without scar formation or any obvious disabilities. In this review, we will first discuss the similarities and differences regarding (i) the distribution of neurogenic niches in the brain of adult zebrafish and mammals (mainly mouse) and (ii) the nature of the neural stem cells within the main telencephalic niches. In the second part, we will describe the cascade of cellular events occurring after telencephalic injury in zebrafish and mouse. Our study clearly shows that most early events happening right after the brain injury are shared between zebrafish and mouse including cell death, microglia, and oligodendrocyte recruitment, as well as injury-induced neurogenesis. In mammals, one of the consequences following an injury is the formation of a glial scar that is persistent. This is not the case in zebrafish, which may be one of the main reasons that zebrafish display a higher regenerative capacity.
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Shah TA, Pallera HK, Kaszowski CL, Bass WT, Lattanzio FA. Therapeutic Hypothermia Inhibits the Classical Complement Pathway in a Rat Model of Neonatal Hypoxic-Ischemic Encephalopathy. Front Neurosci 2021; 15:616734. [PMID: 33642979 PMCID: PMC7907466 DOI: 10.3389/fnins.2021.616734] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 01/25/2021] [Indexed: 01/17/2023] Open
Abstract
OBJECTIVE Complement activation is instrumental in the pathogenesis of Hypoxic-ischemic encephalopathy (HIE), a significant cause of neonatal mortality and disability worldwide. Therapeutic hypothermia (HT), the only available treatment for HIE, only modestly improves outcomes. Complement modulation as a therapeutic adjunct to HT has been considered, but is challenging due to the wide-ranging role of the complement system in neuroinflammation, homeostasis and neurogenesis in the developing brain. We sought to identify potential therapeutic targets by measuring the impact of treatment with HT on complement effector expression in neurons and glia in neonatal HIE, with particular emphasis on the interactions between microglia and C1q. METHODS The Vannucci model was used to induce HIE in term-equivalent rat pups. At P10-12, pups were randomly assigned to three different treatment groups: Sham (control), normothermia (NT), and hypothermia (HT) treatment. Local and systemic complement expression and neuronal apoptosis were measured by ELISA, TUNEL and immunofluorescence labeling, and differences compared between groups. RESULTS Treatment with HT is associated with decreased systemic and microglial expression of C1q, decreased systemic C5a levels, and decreased microglial and neuronal deposition of C3 and C9. The effect of HT on cytokines was variable with decreased expression of pro and anti-inflammatory effectors. HT treatment was associated with decreased C1q binding on cells undergoing apoptosis. CONCLUSION Our data demonstrate the extreme complexity of the immune response in neonatal HIE. We propose modulation of downstream effectors C3a and C5a as a therapeutic adjunct to HT to enhance neuroprotection in the developing brain.
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Affiliation(s)
- Tushar A. Shah
- Department of Pediatrics, Eastern Virginia Medical School, Norfolk, VA, United States
- Department of Microbiology and Molecular Cell Biology, Eastern Virginia Medical School, Norfolk, VA, United States
- Children’s Specialty Group, Norfolk, VA, United States
- Children’s Hospital of The King’s Daughters, Norfolk, VA, United States
| | - Haree K. Pallera
- Department of Pediatrics, Eastern Virginia Medical School, Norfolk, VA, United States
| | | | - William Thomas Bass
- Department of Pediatrics, Eastern Virginia Medical School, Norfolk, VA, United States
- Children’s Specialty Group, Norfolk, VA, United States
- Children’s Hospital of The King’s Daughters, Norfolk, VA, United States
| | - Frank A. Lattanzio
- Department of Physiological Sciences, Eastern Virginia Medical School, Norfolk, VA, United States
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247
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Microglia and Neuroinflammation: What Place for P2RY12? Int J Mol Sci 2021; 22:ijms22041636. [PMID: 33561958 PMCID: PMC7915979 DOI: 10.3390/ijms22041636] [Citation(s) in RCA: 67] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 02/01/2021] [Accepted: 02/03/2021] [Indexed: 12/18/2022] Open
Abstract
Microglia are immune brain cells involved in neuroinflammation. They express a lot of proteins on their surface such as receptors that can be activated by mediators released in the microglial environment. Among these receptors, purinergic receptor expression could be modified depending on the activation status of microglia. In this review, we focus on P2Y receptors and more specifically on P2RY12 that is involved in microglial motility and migration, the first step of neuroinflammation process. We describe the purinergic receptor families, P2RY12 structure, expression and physiological functions. The pharmacological and genetic tools for studying this receptor are detailed thereafter. Last but not least, we report the contribution of microglial P2RY12 to neuroinflammation in acute and chronic brain pathologies in order to better understand P2RY12 microglial role.
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248
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Alboni S, Benatti C, Colliva C, Radighieri G, Blom JMC, Brunello N, Tascedda F. Vortioxetine Prevents Lipopolysaccharide-Induced Memory Impairment Without Inhibiting the Initial Inflammatory Cascade. Front Pharmacol 2021; 11:603979. [PMID: 33613281 PMCID: PMC7890663 DOI: 10.3389/fphar.2020.603979] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 12/16/2020] [Indexed: 01/10/2023] Open
Abstract
Vortioxetine is a novel multimodal antidepressant that modulates a wide range of neurotransmitters throughout the brain. Preclinical and clinical studies have shown that vortioxetine exerts positive effects on different cognitive domains and neuroprotective effects. Considering the key role of microglial cells in brain plasticity and cognition, we aimed at investigating the effects of pretreatment with vortioxetine in modulating behavioral and molecular effects induced by an immune challenge: peripheral injection of lipopolysaccharide (LPS). To this purpose, C57BL/6J male mice were first exposed to a 28-day standard diet or vortioxetine-enriched diet, which was followed by an acute immune challenge with LPS. Sickness symptoms and depressive-like behaviors (anhedonia and memory impairment) were tested 6 and 24 h after exposure to LPS, respectively. Moreover, the expressions of markers of immune activation and M1/M2 markers of microglia polarization were measured in the dorsal and ventral parts of the hippocampus. The pretreatment with vortioxetine did not affect both LPS-induced sickness behavior and anhedonia but prevented the deficit in the recognition memory induced by the immune challenge. At the transcriptional level, chronic exposure to vortioxetine did not prevent LPS-induced upregulation of proinflammatory cytokines 6 h after the immune challenge but rather seemed to potentiate the immune response to the challenge also by affecting the levels of expression of markers of microglia M1 phenotype, like cluster of differentiation (CD)14 and CD86, in an area-dependent manner. However, at the same time point, LPS injection significantly increased the expression of the M2 polarization inducer, interleukin 4, only in the hippocampus of animals chronically exposed to vortioxetine. These results demonstrate that a chronic administration of vortioxetine specifically prevents LPS-induced memory impairment, without affecting acute sickness behavior and anhedonia, and suggest that hippocampal microglia may represent a cellular target of this novel antidepressant medication. Moreover, we provide a useful model to further explore the molecular mechanisms specifically underlying cognitive impairments following an immune challenge.
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Affiliation(s)
- S. Alboni
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
- Centre of Neuroscience and Neurotechnology, University of Modena and Reggio Emilia, Modena, Italy
| | - C. Benatti
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
- Centre of Neuroscience and Neurotechnology, University of Modena and Reggio Emilia, Modena, Italy
| | - C. Colliva
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - G. Radighieri
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - J. M. C. Blom
- Dept. of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy
- Centre of Neuroscience and Neurotechnology, University of Modena and Reggio Emilia, Modena, Italy
| | - N. Brunello
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
- Centre of Neuroscience and Neurotechnology, University of Modena and Reggio Emilia, Modena, Italy
| | - F. Tascedda
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
- Centre of Neuroscience and Neurotechnology, University of Modena and Reggio Emilia, Modena, Italy
- CIB, Consorzio Interuniversitario Biotecnologie, Trieste, Italy
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249
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Comparative Analysis Identifies Similarities between the Human and Murine Microglial Sensomes. Int J Mol Sci 2021; 22:ijms22031495. [PMID: 33540859 PMCID: PMC7867338 DOI: 10.3390/ijms22031495] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 01/26/2021] [Accepted: 01/28/2021] [Indexed: 12/31/2022] Open
Abstract
One of the essential functions of microglia is to continuously sense changes in their environment and adapt to those changes. For this purpose, they use a set of genes termed the sensome. This sensome is comprised of the most abundantly expressed receptors on the surface of microglia. In this study, we updated previously identified mouse microglial sensome by incorporating an additional published RNAseq dataset into the data-analysis pipeline. We also identified members of the human microglial sensome using two independent human microglia RNAseq data sources. Using both the mouse and human microglia sensomes, we identified a key set of genes conserved between the mouse and human microglial sensomes as well as some differences between the species. We found a key set of 57 genes to be conserved in both mouse and human microglial sensomes. We define these genes as the “microglia core sensome”. We then analyzed expression of genes in this core sensome in five different datasets from two neurodegenerative disease models at various stages of the diseases and found that, overall, changes in the level of expression of microglial sensome genes are specific to the disease or condition studied. Our results highlight the relevance of data generated in mice for understanding the biology of human microglia, but also stress the importance of species-specific gene sets for the investigation of diseases involving microglia. Defining this microglial specific core sensome may help identify pathological changes in microglia in humans and mouse models of human disease.
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Grabowski GA, Antommaria AHM, Kolodny EH, Mistry PK. Gaucher disease: Basic and translational science needs for more complete therapy and management. Mol Genet Metab 2021; 132:59-75. [PMID: 33419694 PMCID: PMC8809485 DOI: 10.1016/j.ymgme.2020.12.291] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 11/15/2020] [Accepted: 12/18/2020] [Indexed: 12/12/2022]
Affiliation(s)
- Gregory A Grabowski
- Department of Pediatrics, University of Cincinnati College of Medicine, United States of America; Department of Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati College of Medicine, United States of America; Division of Human Genetics, Cincinnati Children's Research Foundation, Cincinnati, OH, United States of America.
| | - Armand H M Antommaria
- Department of Pediatrics, University of Cincinnati College of Medicine, United States of America; Lee Ault Carter Chair of Pediatric Ethics, Cincinnati Children's Research Foundation, Cincinnati, OH, United States of America.
| | - Edwin H Kolodny
- Department of Neurology, New York University Grossman School of Medicine, New York, NY, United States of America.
| | - Pramod K Mistry
- Departments of Medicine and Pediatrics, Yale School of Medicine, New Haven, CT, United States of America.
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