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Fritze J, Muralidharan C, Stamp E, Ahlenius H. Microglia undergo disease-associated transcriptional activation and CX3C motif chemokine receptor 1 expression regulates neurogenesis in the aged brain. Dev Neurobiol 2024; 84:128-141. [PMID: 38616340 DOI: 10.1002/dneu.22939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 01/31/2024] [Accepted: 03/16/2024] [Indexed: 04/16/2024]
Abstract
Adult neurogenesis continues throughout life but declines dramatically with age and in neurodegenerative disorders such as Alzheimer's disease. In parallel, microglia become activated resulting in chronic inflammation in the aged brain. A unique type of microglia, suggested to support neurogenesis, exists in the subventricular zone (SVZ), but little is known how they are affected by aging. We analyzed the transcriptome of aging microglia and identified a unique neuroprotective activation profile in aged SVZ microglia, which is partly shared with disease-associated microglia (DAM). CX3C motif chemokine receptor 1 (CX3CR1) is characteristically expressed by brain microglia where it directs migration to targets for phagocytosis. We show that Cx3cr1 expression, as in DAM, is downregulated in old SVZ microglia and that heterozygous Cx3cr1 mice have increased proliferation and neuroblast number in the aged SVZ but not in the dentate gyrus, identifying CX3CR1 signaling as a novel age and brain region-specific regulator of neurogenesis.
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Affiliation(s)
- Jonas Fritze
- Department of Experimental Medical Sciences, Faculty of Medicine, Stem Cells, Aging and Neurodegeneration Group, Lund University, Lund, Sweden
- Lund Stem Cell Center, Lund, Sweden
| | - Chandramouli Muralidharan
- Department of Experimental Medical Sciences, Faculty of Medicine, Stem Cells, Aging and Neurodegeneration Group, Lund University, Lund, Sweden
- Lund Stem Cell Center, Lund, Sweden
- Department of Experimental Medical Science, Faculty of Medicine, Molecular Neurogenetics Group, Lund University, Lund, Sweden
| | - Eleanor Stamp
- Department of Experimental Medical Sciences, Faculty of Medicine, Stem Cells, Aging and Neurodegeneration Group, Lund University, Lund, Sweden
- Lund Stem Cell Center, Lund, Sweden
| | - Henrik Ahlenius
- Department of Experimental Medical Sciences, Faculty of Medicine, Stem Cells, Aging and Neurodegeneration Group, Lund University, Lund, Sweden
- Lund Stem Cell Center, Lund, Sweden
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Huuha AM, Norevik CS, Coombes JS, Røsbjørgen RN, Miguel-dos-Santos R, Moreira JBN, Kobro-Flatmoen A, Scrimgeour N, Tari AR. Effects of Intravenously Administered Plasma from Exercise-Trained Donors on Microglia and Cytokines in a Transgenic Rat Model of Alzheimer's Disease. Brain Plast 2024; 9:21-41. [PMID: 38993579 PMCID: PMC11234670 DOI: 10.3233/bpl-230154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/26/2024] [Indexed: 07/13/2024] Open
Abstract
Background Microglia and inflammation play a significant role in Alzheimer's disease (AD). Physical exercise and peripheral signals can influence microglial activity in the brain. Modulating the inflammatory response in the brain may provide therapeutic approaches for AD. Objective To assess the effects of intravenously administered blood plasma from exercise-trained donor rats on cognitive function, microglia, and cytokine levels in an AD rat model at two different pathological stages; an early pre-plaque stage and a later stage closer to the emergence of extracellular plaques. Methods Male transgenic McGill-R-Thy1-APP rats aged 2 and 5 months received 14 injections over 6 weeks: 1) plasma from exercise-trained rats (ExPlas), 2) plasma from sedentary rats (SedPlas), or 3) saline. Cognitive function was evaluated in a novel object recognition task. Microglia count and morphology were analyzed in cornu ammonis, dentate gyrus, entorhinal cortex, and subiculum. Amyloid plaque number and size were assessed in the rats with the later treatment start. A multiplex assay was used to measure 23 cytokines in cornu ammonis. Results In rats treated from 2 months of age, ExPlas and SedPlas increased number and length of microglial branches in cornu ammonis and dentate gyrus compared to saline. Only ExPlas-treated rats exhibited similar changes in subiculum, while entorhinal cortex showed no differences across treatments. Microglia count remained unaffected. In rats treated from 5 months of age, there were no significant differences in microglia count or morphology or the number or size of amyloid plaques in any brain region. Compared to both other treatments in early pre-plaque stage rats, SedPlas increased TNF-α levels. ExPlas upregulated GM-CSF, IL-18, and VEGF, while SedPlas increased IL-10 compared to saline. In later-stage rats, ExPlas upregulated IL-17, and SedPlas upregulated TNF-α compared to saline. There were no effects of treatments on recognition memory. Conclusions Intravenous injections of blood plasma from exercise-trained and sedentary donors differentially modulated microglial morphology and cytokine levels in the AD rat model at an early pre-plaque stage of pathology. Exercised plasma may reduce proinflammatory TNF-α signaling and promote microglial responses to early Aβ accumulation but the lack of treatment effects in the later-stage rats emphasizes the potential importance of treatment timing.
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Affiliation(s)
- Aleksi M. Huuha
- Department of Circulation and Medical Imaging, Cardiac Exercise Research Group (CERG), Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
- Department of Neurology and Clinical Neurophysiology, St. Olavs Hospital, Trondheim University Hospital, Trondheim, Norway
| | - Cecilie Skarstad Norevik
- Department of Circulation and Medical Imaging, Cardiac Exercise Research Group (CERG), Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
- Department of Neurology and Clinical Neurophysiology, St. Olavs Hospital, Trondheim University Hospital, Trondheim, Norway
| | - Jeff S. Coombes
- Centre for Research on Exercise, Physical Activity and Health, School of Human Movement and Nutrition Sciences, The University of Queensland, Brisbane, Australia
| | - Ragnhild N. Røsbjørgen
- Department of Circulation and Medical Imaging, Cardiac Exercise Research Group (CERG), Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
| | - Rodrigo Miguel-dos-Santos
- Department of Circulation and Medical Imaging, Cardiac Exercise Research Group (CERG), Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
- Department of Physiology, Federal University of Sergipe, Sergipe, Brazil
| | - José Bianco N. Moreira
- Department of Circulation and Medical Imaging, Cardiac Exercise Research Group (CERG), Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
| | - Asgeir Kobro-Flatmoen
- Kavli Institute for Systems Neuroscience, Centre for Neural Computation, and Egil and Pauline Braathen and Fred Kavli Centre for Cortical Microcircuits, Norwegian University of Science and Technology, Trondheim, Norway
- K.G. Jebsen Centre for Alzheimer’s Disease, Norwegian University of Science and Technology, Trondheim, Norway
| | - Nathan Scrimgeour
- Department of Circulation and Medical Imaging, Cardiac Exercise Research Group (CERG), Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
| | - Atefe R. Tari
- Department of Circulation and Medical Imaging, Cardiac Exercise Research Group (CERG), Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
- Department of Neurology and Clinical Neurophysiology, St. Olavs Hospital, Trondheim University Hospital, Trondheim, Norway
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3
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Coleman LG. From the dust: extracellular vesicles as regulators of development and neuroregeneration. Neural Regen Res 2024; 19:933-934. [PMID: 37862175 PMCID: PMC10749604 DOI: 10.4103/1673-5374.382243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 05/27/2023] [Accepted: 07/11/2023] [Indexed: 10/22/2023] Open
Affiliation(s)
- Leon G. Coleman
- The University of North Carolina at Chapel Hill, School of Medicine, Department of Pharmacology, Bowles Center for Alcohol Studies, Chapel Hill, NC, USA
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4
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Chintamen S, Gaur P, Vo N, Bradshaw EM, Menon V, Kernie SG. Distinct microglial transcriptomic signatures within the hippocampus. PLoS One 2024; 19:e0296280. [PMID: 38180982 PMCID: PMC10775894 DOI: 10.1371/journal.pone.0296280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2023] [Accepted: 12/08/2023] [Indexed: 01/07/2024] Open
Abstract
Microglia, the resident immune cells of the brain, are crucial in the development of the nervous system. Recent evidence demonstrates that microglia modulate adult hippocampal neurogenesis by inhibiting cell proliferation of neural precursors and survival both in vitro and in vivo, thus maintaining a balance between cell division and cell death in the neural stem cell pool. There are increasing reports suggesting these microglia found in neurogenic niches differ from their counterparts in non-neurogenic areas. Here, we present evidence that hippocampal microglia exhibit transcriptomic heterogeneity, with some cells expressing genes associated with neurogenesis. By comprehensively profiling myeloid lineage cells in the hippocampus using single cell RNA-sequencing, we have uncovered a small, yet distinct population of microglia which exhibit depletion in genes associated with homeostatic microglia and enrichment of genes associated with phagocytosis. Intriguingly, this population also expresses a gene signature with substantial overlap with previously characterized phenotypes, including disease associated microglia (DAM), a particularly unique and compelling microglial state.
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Affiliation(s)
- Sana Chintamen
- Department of Pediatrics, Columbia University College of Physicians and
Surgeons, New York, New York, United States of America
| | - Pallavi Gaur
- Department of Neurology, Columbia University College of Physicians and
Surgeons, New York, New York, United States of America
| | - Nicole Vo
- Department of Neurology, Columbia University College of Physicians and
Surgeons, New York, New York, United States of America
| | - Elizabeth M. Bradshaw
- Department of Neurology, Columbia University College of Physicians and
Surgeons, New York, New York, United States of America
| | - Vilas Menon
- Department of Neurology, Columbia University College of Physicians and
Surgeons, New York, New York, United States of America
| | - Steven G. Kernie
- Department of Pediatrics, Columbia University College of Physicians and
Surgeons, New York, New York, United States of America
- Department of Neurology, Columbia University College of Physicians and
Surgeons, New York, New York, United States of America
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5
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Dutton M, Boyes A, Can AT, Mohamed AZ, Hajishafiee M, Shan ZY, Lagopoulos J, Hermens DF. Hippocampal subfield volumes predict treatment response to oral ketamine in people with suicidality. J Psychiatr Res 2024; 169:192-200. [PMID: 38042058 DOI: 10.1016/j.jpsychires.2023.11.040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 10/31/2023] [Accepted: 11/22/2023] [Indexed: 12/04/2023]
Abstract
Ongoing stress results in hippocampal neuro-structural alterations which produce pathological consequences, including depression and suicidality. Ketamine may ameliorate stress related illnesses, including suicidality, via neuroplasticity processes. This novel study sought to determine whether oral ketamine treatment specifically affects hippocampal (whole and subfield) volumes in patients with chronic suicidality and MDD. It was hypothesised that oral ketamine treatment would differentially alter hippocampal volumes in trial participants categorised as ketamine responders, versus those who were non-responders. Twenty-eight participants received 6 single, weekly doses of oral ketamine (0.5-3 mg/kg) and underwent MRI scans at pre-ketamine (week 0), post-ketamine (week 6), and follow up (week 10). Hippocampal subfield volumes were extracted using the longitudinal pipeline in FreeSurfer. Participants were grouped according to ketamine response status and then compared in terms of grey matter volume (GMV) changes, among 10 hippocampal regions, over 6 and 10 weeks. Mixed ANOVAs were used to analyse interactions between time and group. Post treatment analysis revealed a significant main effect of group for three left hippocampal GMVs as well in the left and right whole hippocampus. Ketamine acute responders (Week 6) showed increased GMVs in both left and right whole hippocampus and in three subfields compared to acute non-responders, across all three timepoints, suggesting that pre-treatment increased hippocampal GMVs (particularly left hemisphere) may be predictive biomarkers of acute treatment response. Future studies should further investigate the potential of hippocampal volumes as a biomarker of ketamine treatment response.
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Affiliation(s)
- Megan Dutton
- Thompson Institute, University of the Sunshine Coast, Queensland, Australia.
| | - Amanda Boyes
- Thompson Institute, University of the Sunshine Coast, Queensland, Australia
| | - Adem T Can
- Thompson Institute, University of the Sunshine Coast, Queensland, Australia
| | - Abdalla Z Mohamed
- Thompson Institute, University of the Sunshine Coast, Queensland, Australia
| | - Maryam Hajishafiee
- Thompson Institute, University of the Sunshine Coast, Queensland, Australia
| | - Zack Y Shan
- Thompson Institute, University of the Sunshine Coast, Queensland, Australia
| | - Jim Lagopoulos
- Thompson Institute, University of the Sunshine Coast, Queensland, Australia
| | - Daniel F Hermens
- Thompson Institute, University of the Sunshine Coast, Queensland, Australia
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Morrison V, Houpert M, Trapani J, Brockman A, Kingsley P, Katdare K, Layden H, Nguena-Jones G, Trevisan A, Maguire-Zeiss K, Marnett L, Bix G, Ihrie R, Carter B. Jedi-1/MEGF12-mediated phagocytosis controls the pro-neurogenic properties of microglia in the ventricular-subventricular zone. Cell Rep 2023; 42:113423. [PMID: 37952151 PMCID: PMC10842823 DOI: 10.1016/j.celrep.2023.113423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 10/03/2023] [Accepted: 10/25/2023] [Indexed: 11/14/2023] Open
Abstract
Microglia are the primary phagocytes in the central nervous system and clear dead cells generated during development or disease. The phagocytic process shapes the microglia phenotype, which affects the local environment. A unique population of microglia resides in the ventricular-subventricular zone (V-SVZ) of neonatal mice, but how they influence the neurogenic niche is not well understood. Here, we demonstrate that phagocytosis contributes to a pro-neurogenic microglial phenotype in the V-SVZ and that these microglia phagocytose apoptotic cells via the engulfment receptor Jedi-1. Deletion of Jedi-1 decreases apoptotic cell clearance, triggering a neuroinflammatory microglia phenotype that resembles dysfunctional microglia in neurodegeneration and aging and that reduces neural precursor proliferation via elevated interleukin-1β signaling; interleukin-1 receptor inhibition rescues precursor proliferation in vivo. Together, these results reveal a critical role for Jedi-1 in connecting microglial phagocytic activity to the maintenance of a pro-neurogenic phenotype in the developing V-SVZ.
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Affiliation(s)
- Vivianne Morrison
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37232, USA; Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN 37235, USA; Department of Cell and Molecular Biology, Tulane University, New Orleans, LA 70118, USA
| | - Matthew Houpert
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37232, USA; Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN 37235, USA
| | - Jonathan Trapani
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37232, USA; Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN 37235, USA
| | - Asa Brockman
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN 37235, USA; Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN 37235, USA
| | - Philip Kingsley
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37232, USA
| | - Ketaki Katdare
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN 37235, USA
| | - Hillary Layden
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37232, USA
| | - Gabriela Nguena-Jones
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37232, USA; Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN 37235, USA
| | - Alexandra Trevisan
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37232, USA; Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | | | - Lawrence Marnett
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37232, USA; Department of Chemistry, Vanderbilt University, Nashville, TN 37235, USA; Department of Pharmacology, Vanderbilt University, Nashville, TN 37235, USA; A.B. Hancock Jr. Memorial Laboratory for Cancer Research, Vanderbilt-Ingram Cancer Center, Nashville, TN 37232, USA
| | - Gregory Bix
- Center for Clinical Neuroscience Research, Tulane University, New Orleans, LA 70118, USA
| | - Rebecca Ihrie
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN 37235, USA; Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN 37235, USA
| | - Bruce Carter
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37232, USA; Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN 37235, USA.
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Li X, Liu H, Han C, Luo J, Guan X, Wang L, Li Y, Wang J, Piao H, Zou W, Liu J. A Human Brain Model Mimicking Umbilical Cord Mesenchymal Stem Cells for the Treatment of Hypoxic-Ischemic Brain Injury. Int J Mol Sci 2023; 24:14208. [PMID: 37762511 PMCID: PMC10532043 DOI: 10.3390/ijms241814208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 09/09/2023] [Accepted: 09/12/2023] [Indexed: 09/29/2023] Open
Abstract
We used an in vitro model of the human brain immune microenvironment to simulate hypoxic-ischemic brain injury (HIBI) and treatment with human umbilical cord mesenchymal stem cells (hUMSCs) to address the transformation barriers of gene differences between animals and humans in preclinical research. A co-culture system, termed hNAME, consisted of human hippocampal neurons (N), astrocytes (A), microglia (M), and brain microvascular endothelial cells (E). Flow cytometry measured the apoptosis rates of neurons and endothelial cells. hNAME-neurons and endothelial cells experienced more severe damage than monolayer cells, particularly after 48 h and 24 h of reoxygenation (OGD48/R24). Western blotting identified neuroinflammatory response markers, including HIF-1α, C1q, C3, TNF-α, and iNOS. Inflammatory factors originated from the glial chamber rather than the neurons and vascular endothelial chambers. A gradual increase in the release of inflammatory factors was observed as the OGD and reoxygenation times increased, peaking at OGD48/R24. The hNAME value was confirmed in human umbilical cord mesenchymal stem cells (hUMSCs). Treatment with hUMSCs resulted in a notable decrease in the severity of neuronal and endothelial cell damage in hNAME. The hNAME is an ideal in vitro model for simulating the immune microenvironment of the human brain because of the interactions between neurons, vessels, astrocytes, and microglia.
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Affiliation(s)
- Xidan Li
- Stem Cell Clinical Research Center, The First Affiliated Hospital of Dalian Medical University, Dalian 116011, China; (X.L.); (H.L.); (C.H.); (J.L.); (X.G.); (L.W.); (Y.L.); (J.W.)
- Liaoning Key Laboratory of Frontier Technology of Stem Cell and Precision Medicine, Dalian Engineering Research Center for Genetic Variation Detection of Infectious Pathogenic Microorganisms, Dalian Innovation Institute of Stem Cell and Precision Medicine, Dalian 116085, China; (H.P.); (W.Z.)
| | - Haijing Liu
- Stem Cell Clinical Research Center, The First Affiliated Hospital of Dalian Medical University, Dalian 116011, China; (X.L.); (H.L.); (C.H.); (J.L.); (X.G.); (L.W.); (Y.L.); (J.W.)
- Liaoning Key Laboratory of Frontier Technology of Stem Cell and Precision Medicine, Dalian Engineering Research Center for Genetic Variation Detection of Infectious Pathogenic Microorganisms, Dalian Innovation Institute of Stem Cell and Precision Medicine, Dalian 116085, China; (H.P.); (W.Z.)
| | - Chao Han
- Stem Cell Clinical Research Center, The First Affiliated Hospital of Dalian Medical University, Dalian 116011, China; (X.L.); (H.L.); (C.H.); (J.L.); (X.G.); (L.W.); (Y.L.); (J.W.)
- Liaoning Key Laboratory of Frontier Technology of Stem Cell and Precision Medicine, Dalian Engineering Research Center for Genetic Variation Detection of Infectious Pathogenic Microorganisms, Dalian Innovation Institute of Stem Cell and Precision Medicine, Dalian 116085, China; (H.P.); (W.Z.)
| | - Jianglin Luo
- Stem Cell Clinical Research Center, The First Affiliated Hospital of Dalian Medical University, Dalian 116011, China; (X.L.); (H.L.); (C.H.); (J.L.); (X.G.); (L.W.); (Y.L.); (J.W.)
- Liaoning Key Laboratory of Frontier Technology of Stem Cell and Precision Medicine, Dalian Engineering Research Center for Genetic Variation Detection of Infectious Pathogenic Microorganisms, Dalian Innovation Institute of Stem Cell and Precision Medicine, Dalian 116085, China; (H.P.); (W.Z.)
| | - Xin Guan
- Stem Cell Clinical Research Center, The First Affiliated Hospital of Dalian Medical University, Dalian 116011, China; (X.L.); (H.L.); (C.H.); (J.L.); (X.G.); (L.W.); (Y.L.); (J.W.)
- Liaoning Key Laboratory of Frontier Technology of Stem Cell and Precision Medicine, Dalian Engineering Research Center for Genetic Variation Detection of Infectious Pathogenic Microorganisms, Dalian Innovation Institute of Stem Cell and Precision Medicine, Dalian 116085, China; (H.P.); (W.Z.)
| | - Liang Wang
- Stem Cell Clinical Research Center, The First Affiliated Hospital of Dalian Medical University, Dalian 116011, China; (X.L.); (H.L.); (C.H.); (J.L.); (X.G.); (L.W.); (Y.L.); (J.W.)
- Liaoning Key Laboratory of Frontier Technology of Stem Cell and Precision Medicine, Dalian Engineering Research Center for Genetic Variation Detection of Infectious Pathogenic Microorganisms, Dalian Innovation Institute of Stem Cell and Precision Medicine, Dalian 116085, China; (H.P.); (W.Z.)
| | - Ying Li
- Stem Cell Clinical Research Center, The First Affiliated Hospital of Dalian Medical University, Dalian 116011, China; (X.L.); (H.L.); (C.H.); (J.L.); (X.G.); (L.W.); (Y.L.); (J.W.)
- Liaoning Key Laboratory of Frontier Technology of Stem Cell and Precision Medicine, Dalian Engineering Research Center for Genetic Variation Detection of Infectious Pathogenic Microorganisms, Dalian Innovation Institute of Stem Cell and Precision Medicine, Dalian 116085, China; (H.P.); (W.Z.)
| | - Jiayi Wang
- Stem Cell Clinical Research Center, The First Affiliated Hospital of Dalian Medical University, Dalian 116011, China; (X.L.); (H.L.); (C.H.); (J.L.); (X.G.); (L.W.); (Y.L.); (J.W.)
- Liaoning Key Laboratory of Frontier Technology of Stem Cell and Precision Medicine, Dalian Engineering Research Center for Genetic Variation Detection of Infectious Pathogenic Microorganisms, Dalian Innovation Institute of Stem Cell and Precision Medicine, Dalian 116085, China; (H.P.); (W.Z.)
| | - Hua Piao
- Liaoning Key Laboratory of Frontier Technology of Stem Cell and Precision Medicine, Dalian Engineering Research Center for Genetic Variation Detection of Infectious Pathogenic Microorganisms, Dalian Innovation Institute of Stem Cell and Precision Medicine, Dalian 116085, China; (H.P.); (W.Z.)
- College of Basic Medical Science, Dalian Medical University, Dalian 116027, China
| | - Wei Zou
- Liaoning Key Laboratory of Frontier Technology of Stem Cell and Precision Medicine, Dalian Engineering Research Center for Genetic Variation Detection of Infectious Pathogenic Microorganisms, Dalian Innovation Institute of Stem Cell and Precision Medicine, Dalian 116085, China; (H.P.); (W.Z.)
| | - Jing Liu
- Stem Cell Clinical Research Center, The First Affiliated Hospital of Dalian Medical University, Dalian 116011, China; (X.L.); (H.L.); (C.H.); (J.L.); (X.G.); (L.W.); (Y.L.); (J.W.)
- Liaoning Key Laboratory of Frontier Technology of Stem Cell and Precision Medicine, Dalian Engineering Research Center for Genetic Variation Detection of Infectious Pathogenic Microorganisms, Dalian Innovation Institute of Stem Cell and Precision Medicine, Dalian 116085, China; (H.P.); (W.Z.)
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8
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Mihailova V, Stoyanova II, Tonchev AB. Glial Populations in the Human Brain Following Ischemic Injury. Biomedicines 2023; 11:2332. [PMID: 37760773 PMCID: PMC10525766 DOI: 10.3390/biomedicines11092332] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 08/14/2023] [Accepted: 08/19/2023] [Indexed: 09/29/2023] Open
Abstract
There is a growing interest in glial cells in the central nervous system due to their important role in maintaining brain homeostasis under physiological conditions and after injury. A significant amount of evidence has been accumulated regarding their capacity to exert either pro-inflammatory or anti-inflammatory effects under different pathological conditions. In combination with their proliferative potential, they contribute not only to the limitation of brain damage and tissue remodeling but also to neuronal repair and synaptic recovery. Moreover, reactive glial cells can modulate the processes of neurogenesis, neuronal differentiation, and migration of neurons in the existing neural circuits in the adult brain. By discovering precise signals within specific niches, the regulation of sequential processes in adult neurogenesis holds the potential to unlock strategies that can stimulate the generation of functional neurons, whether in response to injury or as a means of addressing degenerative neurological conditions. Cerebral ischemic stroke, a condition falling within the realm of acute vascular disorders affecting the circulation in the brain, stands as a prominent global cause of disability and mortality. Extensive investigations into glial plasticity and their intricate interactions with other cells in the central nervous system have predominantly relied on studies conducted on experimental animals, including rodents and primates. However, valuable insights have also been gleaned from in vivo studies involving poststroke patients, utilizing highly specialized imaging techniques. Following the attempts to map brain cells, the role of various transcription factors in modulating gene expression in response to cerebral ischemia is gaining increasing popularity. Although the results obtained thus far remain incomplete and occasionally ambiguous, they serve as a solid foundation for the development of strategies aimed at influencing the recovery process after ischemic brain injury.
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Affiliation(s)
- Victoria Mihailova
- Department of Anatomy and Cell Biology, Faculty of Medicine, Medical University Varna, 9000 Varna, Bulgaria; (I.I.S.); (A.B.T.)
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9
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Alonso Bellido IM, Posada-Pérez M, Hernández-Rasco F, Vázquez-Reyes S, Cabanillas M, Herrera AJ, Bachiller S, Soldán-Hidalgo J, Espinosa-Oliva AM, Joseph B, de Pablos RM, Venero JL, Ruiz R. Microglial Caspase-3 is essential for modulating hippocampal neurogenesis. Brain Behav Immun 2023:S0889-1591(23)00157-5. [PMID: 37327833 DOI: 10.1016/j.bbi.2023.06.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 06/07/2023] [Accepted: 06/10/2023] [Indexed: 06/18/2023] Open
Abstract
Adult hippocampal neurogenesis (AHN) is a process involved in numerous neurodegenerative diseases. Many researchers have described microglia as a key component in regulating the formation and migration of new neurons along the rostral migratory stream. Caspase-3 is a cysteine-aspartate-protease classically considered as one of the main effector caspases in the cell death program process. In addition to this classical function, we have identified the role of this protein as a modulator of microglial function; however, its action on neurogenic processes is unknown. The aim of the present study is to identify the role of Caspase-3 in neurogenesis-related microglial functions. To address this study, Caspase-3 conditional knockout mice in the microglia cell line were used. Using this tool, we wanted to elucidate the role of this protein in microglial function in the hippocampus, the main region in which adult neurogenesis takes place. After the reduction of Caspase-3 in microglia, mutant mice showed a reduction of microglia in the hippocampus, especially in the dentate gyrus region, a region inherently associated to neurogenesis. In addition, we found a reduction in doublecortin-positive neurons in conditional Caspase-3 knockout mice, which corresponds to a reduction in neurogenic neurons. Furthermore, using high-resolution image analysis, we also observed a reduction in the phagocytic capacity of microglia lacking Caspase-3. Behavioral analysis using object recognition and Y-maze tests showed altered memory and learning in the absence of Caspase-3. Finally, we identified specific microglia located specifically in neurogenic niche positive for Galectin 3 which colocalized with Cleaved-Caspase-3 in control mice. Taken together, these results showed the essential role of Caspase-3 in microglial function and highlight the relevant role of this specific microglial phenotype in the maintenance of AHN in the hippocampus.
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Affiliation(s)
- Isabel M Alonso Bellido
- Instituto de Biomedicina de Sevilla, IBiS/Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla, Spain; Departamento de Bioquímica y Biología Molecular, Facultad de Farmacia, Universidad de Sevilla, Spain
| | - Mercedes Posada-Pérez
- Instituto de Biomedicina de Sevilla, IBiS/Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla, Spain; Institute of Environmental Medicine, Toxicology Unit, Karolinska Institutet, Stockholm, Sweden
| | - Francisco Hernández-Rasco
- Instituto de Biomedicina de Sevilla, IBiS/Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla, Spain; Departamento de Bioquímica y Biología Molecular, Facultad de Farmacia, Universidad de Sevilla, Spain
| | - Sandra Vázquez-Reyes
- Instituto de Biomedicina de Sevilla, IBiS/Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla, Spain; Departamento de Bioquímica y Biología Molecular, Facultad de Farmacia, Universidad de Sevilla, Spain
| | - María Cabanillas
- Instituto de Biomedicina de Sevilla, IBiS/Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla, Spain; Departamento de Bioquímica y Biología Molecular, Facultad de Farmacia, Universidad de Sevilla, Spain
| | - Antonio J Herrera
- Instituto de Biomedicina de Sevilla, IBiS/Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla, Spain; Departamento de Bioquímica y Biología Molecular, Facultad de Farmacia, Universidad de Sevilla, Spain
| | - Sara Bachiller
- Instituto de Biomedicina de Sevilla, IBiS/Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla, Spain; Clinical Unit of Infectious Diseases, Microbiology and Parasitology, Laboratory of Immunovirology, Virgen del Rocío University Hospital, Seville, Spain; Department of Medical Biochemistry, Molecular Biology and Immunology, School of Medicine, University of Seville, Seville, Spain
| | - Jesús Soldán-Hidalgo
- Instituto de Biomedicina de Sevilla, IBiS/Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla, Spain; Departamento de Bioquímica y Biología Molecular, Facultad de Farmacia, Universidad de Sevilla, Spain
| | - Ana M Espinosa-Oliva
- Instituto de Biomedicina de Sevilla, IBiS/Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla, Spain; Departamento de Bioquímica y Biología Molecular, Facultad de Farmacia, Universidad de Sevilla, Spain
| | - Bertrand Joseph
- Institute of Environmental Medicine, Toxicology Unit, Karolinska Institutet, Stockholm, Sweden
| | - Rocío M de Pablos
- Instituto de Biomedicina de Sevilla, IBiS/Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla, Spain; Departamento de Bioquímica y Biología Molecular, Facultad de Farmacia, Universidad de Sevilla, Spain
| | - José L Venero
- Instituto de Biomedicina de Sevilla, IBiS/Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla, Spain; Departamento de Bioquímica y Biología Molecular, Facultad de Farmacia, Universidad de Sevilla, Spain
| | - Rocío Ruiz
- Instituto de Biomedicina de Sevilla, IBiS/Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla, Spain; Departamento de Bioquímica y Biología Molecular, Facultad de Farmacia, Universidad de Sevilla, Spain.
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10
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Morrison VE, Houpert MG, Trapani JB, Brockman AA, Kingsley PJ, Katdare KA, Layden HM, Nguena-Jones G, Trevisan AJ, Maguire-Zeiss KA, Marnett LJ, Bix GJ, Ihrie RA, Carter BD. Jedi-1/MEGF12-mediated phagocytosis controls the pro-neurogenic properties of microglia in the ventricular-subventricular zone. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.03.531012. [PMID: 36945622 PMCID: PMC10028845 DOI: 10.1101/2023.03.03.531012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/09/2023]
Abstract
Microglia are the primary phagocytes in the central nervous system and are responsible for clearing dead cells generated during development or disease. The phagocytic process shapes the phenotype of the microglia, which affects the local environment. A unique population of microglia reside in the ventricular-subventricular zone (V-SVZ) of neonatal mice, but how they influence this neurogenic niche is not well-understood. Here, we demonstrate that phagocytosis creates a pro-neurogenic microglial phenotype in the V-SVZ and that these microglia phagocytose apoptotic cells via the engulfment receptor Jedi-1. Deletion of Jedi-1 decreases apoptotic cell clearance, triggering the development of a neuroinflammatory phenotype, reminiscent of neurodegenerative and-age-associated microglia, that reduces neural precursor proliferation via elevated interleukin (IL)-1β signaling; inhibition of IL-1 receptor rescues precursor proliferation in vivo. Together, these results reveal a critical role for Jedi-1 in connecting microglial phagocytic activity to a phenotype that promotes neurogenesis in the developing V-SVZ.
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Affiliation(s)
- Vivianne E Morrison
- Vanderbilt University Department of Biochemistry
- Vanderbilt Brain Institute
- Tulane University Center for Clinical Neuroscience Research
| | - Matthew G Houpert
- Vanderbilt University Department of Biochemistry
- Vanderbilt Brain Institute
| | - Jonathan B Trapani
- Vanderbilt University Department of Biochemistry
- Vanderbilt Brain Institute
| | - Asa A Brockman
- Vanderbilt University Department of Cell and Developmental Biology
- Vanderbilt Brain Institute
| | | | | | | | | | - Alexandra J Trevisan
- Vanderbilt University Department of Biochemistry
- St. Jude Children's Research Hospital
| | | | - Lawrence J Marnett
- Vanderbilt University Department of Biochemistry
- Vanderbilt University Department of Chemistry
- Vanderbilt University Department of Pharmacology
- A.B. Hancock Jr. Memorial Laboratory for Cancer Research
| | - Gregory J Bix
- Tulane University Center for Clinical Neuroscience Research
| | - Rebecca A Ihrie
- Vanderbilt University Department of Cell and Developmental Biology
- Vanderbilt Brain Institute
| | - Bruce D Carter
- Vanderbilt University Department of Biochemistry
- Vanderbilt Brain Institute
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11
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Salta E, Lazarov O, Fitzsimons CP, Tanzi R, Lucassen PJ, Choi SH. Adult hippocampal neurogenesis in Alzheimer's disease: A roadmap to clinical relevance. Cell Stem Cell 2023; 30:120-136. [PMID: 36736288 PMCID: PMC10082636 DOI: 10.1016/j.stem.2023.01.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2022] [Revised: 01/09/2023] [Accepted: 01/10/2023] [Indexed: 02/05/2023]
Abstract
Adult hippocampal neurogenesis (AHN) drops sharply during early stages of Alzheimer's disease (AD), via unknown mechanisms, and correlates with cognitive status in AD patients. Understanding AHN regulation in AD could provide a framework for innovative pharmacological interventions. We here combine molecular, behavioral, and clinical data and critically discuss the multicellular complexity of the AHN niche in relation to AD pathophysiology. We further present a roadmap toward a better understanding of the role of AHN in AD by probing the promises and caveats of the latest technological advancements in the field and addressing the conceptual and methodological challenges ahead.
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Affiliation(s)
- Evgenia Salta
- Laboratory of Neurogenesis and Neurodegeneration, Netherlands Institute for Neuroscience, Meibergdreef 47, 1105 BA, Amsterdam, The Netherlands
| | - Orly Lazarov
- Department of Anatomy and Cell Biology, College of Medicine, The University of Illinois at Chicago, 808 S Wood St., Chicago, IL 60612, USA
| | - Carlos P Fitzsimons
- Brain Plasticity group, Swammerdam Institute for Life Sciences, Faculty of Science, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, The Netherlands
| | - Rudolph Tanzi
- Genetics and Aging Research Unit, MassGeneral Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, McCance Center for Brain Health, 114 16th Street, Boston, MA 02129, USA.
| | - Paul J Lucassen
- Brain Plasticity group, Swammerdam Institute for Life Sciences, Faculty of Science, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, The Netherlands; Center for Urban Mental Health, University of Amsterdam, Kruislaan 404, 1098 SM, Amsterdam, The Netherlands.
| | - Se Hoon Choi
- Genetics and Aging Research Unit, MassGeneral Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, McCance Center for Brain Health, 114 16th Street, Boston, MA 02129, USA.
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12
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Andoh M, Koyama R. Microglia and GABA: Diverse functions of microglia beyond GABA-receiving cells. Neurosci Res 2023; 187:52-57. [PMID: 36152917 DOI: 10.1016/j.neures.2022.09.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Accepted: 09/19/2022] [Indexed: 11/18/2022]
Abstract
Neurotransmitters modulate intracellular signaling not only in neurons but also in glial cells such as astrocytes, which form tripartite synapses, and oligodendrocytes, which produce the myelin sheath on axons. Another major glial cell type, microglia, which are often referred to as brain-resident immune cells, also express receptors for neurotransmitters. Recent studies have mainly focused on excitatory neurotransmitters such as glutamate, and few have examined microglial responses to the inhibitory neurotransmitter GABA. Microglia can also structurally and functionally modulate inhibitory neuronal circuits, but the underlying molecular mechanisms remain largely unknown. Since the well-regulated balance of excitatory/inhibitory (E/I) neurotransmission is believed to be the basis of proper brain function, understanding how microglia regulate and respond to inhibitory neurotransmission will help us deepen our knowledge of neuron-glia interactions. In this review, we discuss the mechanisms by which GABA alters microglial behavior and the possibility that microglia are more than just GABA-receiving cells.
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Affiliation(s)
- Megumi Andoh
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan
| | - Ryuta Koyama
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-0033, Japan; Institute for AI and Beyond, The University of Tokyo, Tokyo 113-0033, Japan.
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13
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Tassinari M, Mottolese N, Galvani G, Ferrara D, Gennaccaro L, Loi M, Medici G, Candini G, Rimondini R, Ciani E, Trazzi S. Luteolin Treatment Ameliorates Brain Development and Behavioral Performance in a Mouse Model of CDKL5 Deficiency Disorder. Int J Mol Sci 2022; 23:ijms23158719. [PMID: 35955854 PMCID: PMC9369425 DOI: 10.3390/ijms23158719] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 07/28/2022] [Accepted: 08/03/2022] [Indexed: 12/16/2022] Open
Abstract
CDKL5 deficiency disorder (CDD), a rare and severe neurodevelopmental disease caused by mutations in the X-linked CDKL5 gene, is characterized by early-onset epilepsy, intellectual disability, and autistic features. Although pharmacotherapy has shown promise in the CDD mouse model, safe and effective clinical treatments are still far off. Recently, we found increased microglial activation in the brain of a mouse model of CDD, the Cdkl5 KO mouse, suggesting that a neuroinflammatory state, known to be involved in brain maturation and neuronal dysfunctions, may contribute to the pathophysiology of CDD. The present study aims to evaluate the possible beneficial effect of treatment with luteolin, a natural flavonoid known to have anti-inflammatory and neuroprotective activities, on brain development and behavior in a heterozygous Cdkl5 (+/−) female mouse, the mouse model of CDD that best resembles the genetic clinical condition. We found that inhibition of neuroinflammation by chronic luteolin treatment ameliorates motor stereotypies, hyperactive profile and memory ability in Cdkl5 +/− mice. Luteolin treatment also increases hippocampal neurogenesis and improves dendritic spine maturation and dendritic arborization of hippocampal and cortical neurons. These findings show that microglia overactivation exerts a harmful action in the Cdkl5 +/− brain, suggesting that treatments aimed at counteracting the neuroinflammatory process should be considered as a promising adjuvant therapy for CDD.
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Affiliation(s)
- Marianna Tassinari
- Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy
| | - Nicola Mottolese
- Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy
| | - Giuseppe Galvani
- Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy
| | - Domenico Ferrara
- Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy
| | - Laura Gennaccaro
- Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy
| | - Manuela Loi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy
| | - Giorgio Medici
- Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy
| | - Giulia Candini
- Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy
| | - Roberto Rimondini
- Department of Medical and Surgical Sciences, University of Bologna, 40126 Bologna, Italy
| | - Elisabetta Ciani
- Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy
| | - Stefania Trazzi
- Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy
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14
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Liu Q, Huang Y, Duan M, Yang Q, Ren B, Tang F. Microglia as Therapeutic Target for Radiation-Induced Brain Injury. Int J Mol Sci 2022; 23:ijms23158286. [PMID: 35955439 PMCID: PMC9368164 DOI: 10.3390/ijms23158286] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 07/22/2022] [Accepted: 07/25/2022] [Indexed: 12/10/2022] Open
Abstract
Radiation-induced brain injury (RIBI) after radiotherapy has become an increasingly important factor affecting the prognosis of patients with head and neck tumor. With the delivery of high doses of radiation to brain tissue, microglia rapidly transit to a pro-inflammatory phenotype, upregulate phagocytic machinery, and reduce the release of neurotrophic factors. Persistently activated microglia mediate the progression of chronic neuroinflammation, which may inhibit brain neurogenesis leading to the occurrence of neurocognitive disorders at the advanced stage of RIBI. Fully understanding the microglial pathophysiology and cellular and molecular mechanisms after irradiation may facilitate the development of novel therapy by targeting microglia to prevent RIBI and subsequent neurological and neuropsychiatric disorders.
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Affiliation(s)
- Qun Liu
- The School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou 434023, China; (Q.L.); (Y.H.)
| | - Yan Huang
- The School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou 434023, China; (Q.L.); (Y.H.)
| | - Mengyun Duan
- Department of Pharmacology, School of Medicine, Yangtze University, Jingzhou 434023, China; (M.D.); (Q.Y.)
| | - Qun Yang
- Department of Pharmacology, School of Medicine, Yangtze University, Jingzhou 434023, China; (M.D.); (Q.Y.)
| | - Boxu Ren
- The School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou 434023, China; (Q.L.); (Y.H.)
- Correspondence: (B.R.); (F.T.)
| | - Fengru Tang
- Radiation Physiology Laboratory, Singapore Nuclear Research and Safety Initiative, National University of Singapore, Singapore 138602, Singapore
- Correspondence: (B.R.); (F.T.)
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15
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Cao H, Zuo C, Gu Z, Huang Y, Yang Y, Zhu L, Jiang Y, Wang F. High frequency repetitive transcranial magnetic stimulation alleviates cognitive deficits in 3xTg-AD mice by modulating the PI3K/Akt/GLT-1 Axis. Redox Biol 2022; 54:102354. [PMID: 35660628 PMCID: PMC9168605 DOI: 10.1016/j.redox.2022.102354] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 05/20/2022] [Accepted: 05/24/2022] [Indexed: 12/12/2022] Open
Abstract
Objective Glutamate mediated excitotoxicity, such as oxidative stress, neuroinflammation, synaptic loss and neuronal death, is ubiquitous in Alzheimer's disease (AD). Our previous study found that 15 Hz repetitive transcranial magnetic stimulation (rTMS) could reduce cortical excitability. The purpose of this study was to explore the therapeutic effect of higher frequency rTMS on 3xTg-AD model mice and further explore the mechanisms of rTMS. Methods First, WT and 3xTg-AD model mice received 25 Hz rTMS treatment for 21 days. The Morris water maze test was used to evaluate the cognitive function. The levels of Aβ and neuroinflammation were assessed by ELISA and immunofluorescence. Oxidative stress was quantified by biochemical assay kits. Brain glucose metabolism was assessed by 18F-FDG PET. Apoptosis was assessed by western blot and TUNEL staining. Synaptic plasticity and PI3K/Akt/GLT-1 pathway related protein expression were assessed by western blot. Next, to explore the activity of PI3K/Akt in the therapeutic effect of rTMS, 3xTg-AD model mice were given LY294002 intervention and rTMS treatment for 21 days, the experimental method was the same as before. Results We found that 25 Hz rTMS could improve cognitive function of 3xTg-AD model mice, reduce hippocampal Aβ1-42 levels, ameliorate oxidative stress and improve glucose metabolism. rTMS alleviated neuroinflammatory response, enhanced synaptic plasticity and reduced neuronal loss and cell apoptosis, accompanied by activation of PI3K/Akt/GLT-1 pathway. After administration of PI3K/Akt inhibitor LY294002, 25 Hz rTMS could not improve the cognitive function and reduce neuron damage of 3xTg-AD model mice, nor could it upregulate the expression of GLT-1, indicating that its therapeutic and protective effects required the involvement of PI3K/Akt/GLT-1 pathway. Conclusion rTMS exerts protective role for AD through regulating multiple pathological processes. Meanwhile, this study revealed the key role of PI3K/Akt/GLT-1 pathway in the treatment of AD by rTMS, which might be a new target.
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Affiliation(s)
- Huan Cao
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No.1095 Jiefang Road, Wuhan, 430030, Hubei, China
| | - Chengchao Zuo
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No.1095 Jiefang Road, Wuhan, 430030, Hubei, China
| | - Zhongya Gu
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No.1095 Jiefang Road, Wuhan, 430030, Hubei, China
| | - Yaqi Huang
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No.1095 Jiefang Road, Wuhan, 430030, Hubei, China
| | - Yuyan Yang
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No.1095 Jiefang Road, Wuhan, 430030, Hubei, China
| | - Liudi Zhu
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No.1095 Jiefang Road, Wuhan, 430030, Hubei, China
| | - Yongsheng Jiang
- Cancer Center of Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No.1095 Jiefang Road, Wuhan, 430030, China
| | - Furong Wang
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, No.1095 Jiefang Road, Wuhan, 430030, Hubei, China.
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16
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Starovoytova IA, Dominova IN. An in vitro Study of the Effect of Bacterial Lipopolysaccharide on Transcription Levels of SLC Family Transporter Genes in Microglia. J EVOL BIOCHEM PHYS+ 2022. [DOI: 10.1134/s0022093022020193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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17
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Zou J, Walter TJ, Barnett A, Rohlman A, Crews FT, Coleman LG. Ethanol Induces Secretion of Proinflammatory Extracellular Vesicles That Inhibit Adult Hippocampal Neurogenesis Through G9a/GLP-Epigenetic Signaling. Front Immunol 2022; 13:866073. [PMID: 35634322 PMCID: PMC9136051 DOI: 10.3389/fimmu.2022.866073] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Accepted: 04/07/2022] [Indexed: 12/15/2022] Open
Abstract
Adult hippocampal neurogenesis (AHN) is involved in learning and memory as well as regulation of mood. Binge ethanol reduces AHN, though the mechanism is unknown. Microglia in the neurogenic niche are important regulators of AHN, and ethanol promotes proinflammatory microglia activation. We recently reported that extracellular vesicles (EVs) mediate ethanol-induced inflammatory signaling in microglia. Therefore, we investigated the role of EVs in ethanol-induced loss of adult hippocampal neurogenesis. At rest, microglia promoted neurogenesis through the secretion of pro-neurogenic extracellular vesicles (pn-EVs). Depletion of microglia using colony-stimulating factor 1 receptor (CSFR1) inhibition in vivo or using ex vivo organotypic brain slice cultures (OBSCs) caused a 30% and 56% loss of neurogenesis in the dentate, respectively, as measured by immunohistochemistry for doublecortin (DCX). Likewise, chemogenetic inhibition of microglia using a CD68.hM4di construct caused a 77% loss in OBSC, indicating a pro-neurogenic resting microglial phenotype. EVs from control OBSC were pro-neurogenic (pn-EVs), enhancing neurogenesis when transferred to other naive OBSC and restoring neurogenesis in microglia-depleted cultures. Ethanol inhibited neurogenesis and caused secretion of proinflammatory EVs (EtOH-EVs). EtOH-EVs reduced hippocampal neurogenesis in naïve OBSC by levels similar to ethanol. Neurogenesis involves complex regulation of chromatin structure that could involve EV signaling. Accordingly, EtOH-EVs were found to be enriched with mRNA for the euchromatin histone lysine methyltransferase (Ehm2t/G9a), an enzyme that reduces chromatin accessibility through histone-3 lysine-9 di-methylation (H3K9me2). EtOH-EVs induced G9a and H3K9me2 by 2-fold relative to pn-EVs in naïve OBSCs. Pharmacological inhibition of G9a with either BIX-01294 or UNC0642 prevented loss of neurogenesis caused by both EtOH and EtOH-EVs. Thus, this work finds that proinflammatory EtOH-EVs promote the loss of adult hippocampal neurogenesis through G9a-mediated epigenetic modification of chromatin structure.
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Affiliation(s)
- Jian Zou
- Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, United States
| | - T. Jordan Walter
- Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, United States
| | - Alexandra Barnett
- Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, United States
| | - Aaron Rohlman
- Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, United States
| | - Fulton T. Crews
- Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, United States
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, United States
- Department of Psychiatry, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, United States
| | - Leon G. Coleman
- Bowles Center for Alcohol Studies, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, United States
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, United States
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18
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Arredondo SB, Valenzuela-Bezanilla D, Santibanez SH, Varela-Nallar L. Wnt signaling in the adult hippocampal neurogenic niche. Stem Cells 2022; 40:630-640. [PMID: 35446432 DOI: 10.1093/stmcls/sxac027] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 03/29/2022] [Indexed: 11/14/2022]
Abstract
The subgranular zone (SGZ) of the hippocampal dentate gyrus (DG) is a neurogenic niche of the adult brain that contains neural stem cells (NSCs) able to generate excitatory glutamatergic granule neurons, which integrate into the DG circuit and contribute to hippocampal plasticity, learning, and memory. Thus, endogenous NSCs could be harnessed for therapeutic purposes. In this context, it is critical to characterize the molecular mechanisms controlling the generation and functional integration of adult-born neurons. Adult hippocampal neurogenesis is tightly controlled by both cell-autonomous mechanisms and the interaction with the complex niche microenvironment, which harbors the NSCs and provides the signals to support their maintenance, activation, and differentiation. Among niche-derived factors, Wnt ligands play diverse roles. Wnts are secreted glycoproteins that bind to Frizzled receptors and co-receptors to trigger the Wnt signaling pathway. Here, we summarize the current knowledge about the roles of Wnts in the regulation of adult hippocampal neurogenesis. We discuss the possible contribution of the different niche cells to the regulation of local Wnt signaling activity, and how Wnts derived from different cell types could induce differential effects. Finally, we discuss how the effects of Wnt signaling on hippocampal network activity might contribute to neurogenesis regulation. Although the evidence supports relevant roles for Wnt signaling in adult hippocampal neurogenesis, defining the cellular source and the mechanisms controlling secretion and diffusion of Wnts will be crucial to further understand Wnt signaling regulation of adult NSCs, and eventually, to propose this pathway as a therapeutic target to promote neurogenesis.
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Affiliation(s)
- Sebastian B Arredondo
- Institute of Biomedical Sciences, Faculty of Medicine and Faculty of Life Sciences, Universidad Andres Bello, Echaurren 183, 8370071, Santiago, Chile
| | - Daniela Valenzuela-Bezanilla
- Institute of Biomedical Sciences, Faculty of Medicine and Faculty of Life Sciences, Universidad Andres Bello, Echaurren 183, 8370071, Santiago, Chile
| | - Sebastian H Santibanez
- Institute of Biomedical Sciences, Faculty of Medicine and Faculty of Life Sciences, Universidad Andres Bello, Echaurren 183, 8370071, Santiago, Chile
| | - Lorena Varela-Nallar
- Institute of Biomedical Sciences, Faculty of Medicine and Faculty of Life Sciences, Universidad Andres Bello, Echaurren 183, 8370071, Santiago, Chile
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19
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Rimmerman N, Verdiger H, Goldenberg H, Naggan L, Robinson E, Kozela E, Gelb S, Reshef R, Ryan KM, Ayoun L, Refaeli R, Ashkenazi E, Schottlender N, Ben Hemo-Cohen L, Pienica C, Aharonian M, Dinur E, Lazar K, McLoughlin DM, Zvi AB, Yirmiya R. Microglia and their LAG3 checkpoint underlie the antidepressant and neurogenesis-enhancing effects of electroconvulsive stimulation. Mol Psychiatry 2022; 27:1120-1135. [PMID: 34650207 DOI: 10.1038/s41380-021-01338-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 09/16/2021] [Accepted: 10/01/2021] [Indexed: 12/21/2022]
Abstract
Despite evidence implicating microglia in the etiology and pathophysiology of major depression, there is paucity of information regarding the contribution of microglia-dependent molecular pathways to antidepressant procedures. In this study, we investigated the role of microglia in a mouse model of depression (chronic unpredictable stress-CUS) and its reversal by electroconvulsive stimulation (ECS), by examining the effects of microglia depletion with the colony stimulating factor-1 antagonist PLX5622. Microglia depletion did not change basal behavioral measures or the responsiveness to CUS, but it completely abrogated the therapeutic effects of ECS on depressive-like behavior and neurogenesis impairment. Treatment with the microglia inhibitor minocycline concurrently with ECS also diminished the antidepressant and pro-neurogenesis effects of ECS. Hippocampal RNA-Seq analysis revealed that ECS significantly increased the expression of genes related to neurogenesis and dopamine signaling, while reducing the expression of several immune checkpoint genes, particularly lymphocyte-activating gene-3 (Lag3), which was the only microglial transcript significantly altered by ECS. None of these molecular changes occurred in microglia-depleted mice. Immunohistochemical analyses showed that ECS reversed the CUS-induced changes in microglial morphology and elevation in microglial LAG3 receptor expression. Consistently, either acute or chronic systemic administration of a LAG3 monoclonal antibody, which readily penetrated into the brain parenchyma and was found to serve as a direct checkpoint blocker in BV2 microglia cultures, rapidly rescued the CUS-induced microglial alterations, depressive-like symptoms, and neurogenesis impairment. These findings suggest that brain microglial LAG3 represents a promising target for novel antidepressant therapeutics.
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Affiliation(s)
- Neta Rimmerman
- Department of Psychology, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Hodaya Verdiger
- Department of Psychology, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Hagar Goldenberg
- Department of Psychology, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Lior Naggan
- Department of Psychology, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Elad Robinson
- Department of Psychology, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Ewa Kozela
- Department of Psychology, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Sivan Gelb
- Department of Developmental Biology and Cancer Research, The Institute for Medical Research Israel-Canada, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Ronen Reshef
- Department of Psychology, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Karen M Ryan
- Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin, Ireland.,Department of Psychiatry, Trinity College Dublin, St. Patrick's University Hospital, James Street, Dublin, Ireland
| | - Lily Ayoun
- Department of Psychology, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Ron Refaeli
- Edmond & Lily Safra Center for Brain Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Einat Ashkenazi
- Department of Psychology, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Nofar Schottlender
- Department of Psychology, The Hebrew University of Jerusalem, Jerusalem, Israel
| | | | - Claudia Pienica
- Department of Psychology, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Maayan Aharonian
- Department of Psychology, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Eyal Dinur
- Department of Psychology, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Koby Lazar
- Department of Psychology, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Declan M McLoughlin
- Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin, Ireland.,Department of Psychiatry, Trinity College Dublin, St. Patrick's University Hospital, James Street, Dublin, Ireland
| | - Ayal Ben Zvi
- Department of Developmental Biology and Cancer Research, The Institute for Medical Research Israel-Canada, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Raz Yirmiya
- Department of Psychology, The Hebrew University of Jerusalem, Jerusalem, Israel.
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20
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Craig CF, Filippone RT, Stavely R, Bornstein JC, Apostolopoulos V, Nurgali K. Neuroinflammation as an etiological trigger for depression comorbid with inflammatory bowel disease. J Neuroinflammation 2022; 19:4. [PMID: 34983592 PMCID: PMC8729103 DOI: 10.1186/s12974-021-02354-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 12/14/2021] [Indexed: 02/06/2023] Open
Abstract
Patients with inflammatory bowel disease (IBD) suffer from depression at higher rates than the general population. An etiological trigger of depressive symptoms is theorised to be inflammation within the central nervous system. It is believed that heightened intestinal inflammation and dysfunction of the enteric nervous system (ENS) contribute to impaired intestinal permeability, which facilitates the translocation of intestinal enterotoxins into the blood circulation. Consequently, these may compromise the immunological and physiological functioning of distant non-intestinal tissues such as the brain. In vivo models of colitis provide evidence of increased blood–brain barrier permeability and enhanced central nervous system (CNS) immune activity triggered by intestinal enterotoxins and blood-borne inflammatory mediators. Understanding the immunological, physiological, and structural changes associated with IBD and neuroinflammation may aid in the development of more tailored and suitable pharmaceutical treatment for IBD-associated depression.
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Affiliation(s)
- Colin F Craig
- Institute for Heath and Sport, Victoria University, Western Centre for Health, Research and Education, Sunshine Hospital, Melbourne, VIC, Australia
| | - Rhiannon T Filippone
- Institute for Heath and Sport, Victoria University, Western Centre for Health, Research and Education, Sunshine Hospital, Melbourne, VIC, Australia
| | - Rhian Stavely
- Institute for Heath and Sport, Victoria University, Western Centre for Health, Research and Education, Sunshine Hospital, Melbourne, VIC, Australia.,Department of Pediatric Surgery, Pediatric Surgery Research Laboratories, Massachusetts General Hospital, Harvard Medical School, Boston, MA, 02114, USA
| | - Joel C Bornstein
- Department of Anatomy and Physiology, The University of Melbourne, Melbourne, Australia
| | - Vasso Apostolopoulos
- Institute for Heath and Sport, Victoria University, Western Centre for Health, Research and Education, Sunshine Hospital, Melbourne, VIC, Australia.,Immunology Program, Australian Institute of Musculoskeletal Science (AIMSS), Melbourne, VIC, Australia
| | - Kulmira Nurgali
- Institute for Heath and Sport, Victoria University, Western Centre for Health, Research and Education, Sunshine Hospital, Melbourne, VIC, Australia. .,Department of Medicine Western Health, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Melbourne, VIC, Australia. .,Regenerative Medicine and Stem Cells Program, Australian Institute of Musculoskeletal Science (AIMSS), Melbourne, VIC, Australia. .,Institute for Health and Sport, Victoria University, Level 4 Research Labs, Western Centre for Health Research and Education, Sunshine Hospital, 176 Furlong Road, St Albans, VIC, 3021, Australia.
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21
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Penning A, Tosoni G, Abiega O, Bielefeld P, Gasperini C, De Pietri Tonelli D, Fitzsimons CP, Salta E. Adult Neural Stem Cell Regulation by Small Non-coding RNAs: Physiological Significance and Pathological Implications. Front Cell Neurosci 2022; 15:781434. [PMID: 35058752 PMCID: PMC8764185 DOI: 10.3389/fncel.2021.781434] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 12/09/2021] [Indexed: 01/11/2023] Open
Abstract
The adult neurogenic niches are complex multicellular systems, receiving regulatory input from a multitude of intracellular, juxtacrine, and paracrine signals and biological pathways. Within the niches, adult neural stem cells (aNSCs) generate astrocytic and neuronal progeny, with the latter predominating in physiological conditions. The new neurons generated from this neurogenic process are functionally linked to memory, cognition, and mood regulation, while much less is known about the functional contribution of aNSC-derived newborn astrocytes and adult-born oligodendrocytes. Accumulating evidence suggests that the deregulation of aNSCs and their progeny can impact, or can be impacted by, aging and several brain pathologies, including neurodevelopmental and mood disorders, neurodegenerative diseases, and also by insults, such as epileptic seizures, stroke, or traumatic brain injury. Hence, understanding the regulatory underpinnings of aNSC activation, differentiation, and fate commitment could help identify novel therapeutic avenues for a series of pathological conditions. Over the last two decades, small non-coding RNAs (sncRNAs) have emerged as key regulators of NSC fate determination in the adult neurogenic niches. In this review, we synthesize prior knowledge on how sncRNAs, such as microRNAs (miRNAs) and piwi-interacting RNAs (piRNAs), may impact NSC fate determination in the adult brain and we critically assess the functional significance of these events. We discuss the concepts that emerge from these examples and how they could be used to provide a framework for considering aNSC (de)regulation in the pathogenesis and treatment of neurological diseases.
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Affiliation(s)
- Amber Penning
- Laboratory of Neurogenesis and Neurodegeneration, Netherlands Institute for Neuroscience, Amsterdam, Netherlands
| | - Giorgia Tosoni
- Laboratory of Neurogenesis and Neurodegeneration, Netherlands Institute for Neuroscience, Amsterdam, Netherlands
| | - Oihane Abiega
- Swammerdam Institute for Life Sciences, Faculty of Science, University of Amsterdam, Amsterdam, Netherlands
| | - Pascal Bielefeld
- Swammerdam Institute for Life Sciences, Faculty of Science, University of Amsterdam, Amsterdam, Netherlands
| | - Caterina Gasperini
- Neurobiology of miRNAs Lab, Istituto Italiano di Tecnologia, Genova, Italy
| | | | - Carlos P. Fitzsimons
- Swammerdam Institute for Life Sciences, Faculty of Science, University of Amsterdam, Amsterdam, Netherlands
- *Correspondence: Carlos Fitzsimons Evgenia Salta
| | - Evgenia Salta
- Laboratory of Neurogenesis and Neurodegeneration, Netherlands Institute for Neuroscience, Amsterdam, Netherlands
- *Correspondence: Carlos Fitzsimons Evgenia Salta
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22
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Fauser M, Loewenbrück KF, Rangnick J, Brandt MD, Hermann A, Storch A. Adult Neural Stem Cells from Midbrain Periventricular Regions Show Limited Neurogenic Potential after Transplantation into the Hippocampal Neurogenic Niche. Cells 2021; 10:3021. [PMID: 34831242 PMCID: PMC8616334 DOI: 10.3390/cells10113021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Accepted: 10/29/2021] [Indexed: 11/20/2022] Open
Abstract
The regulation of adult neural stem or progenitor cell (aNSC) proliferation and differentiation as an interplay of cell-intrinsic and local environmental cues remains in part unclear, impeding their role in putative regenerative therapies. aNSCs with all major properties of NSCs in vitro have been identified in a variety of brain regions beyond the classic neurogenic niches, including the caudal periventricular regions (PVRs) of the midbrain, though active neurogenesis is either limited or merely absent in these regions. To elucidate cell-intrinsic properties of aNSCs from various PVRs, we here examined the proliferation and early differentiation capacity of murine aNSCs from non-neurogenic midbrain PVRs (PVRMB) compared to aNSCs from the neurogenic ventricular-subventricular zone (PVRV-SVZ) 7 days after transplantation into the permissive pro-neurogenic niche of the dentate gyrus (DG) of the hippocampus in mice. An initial in vitro characterization of the transplants displayed very similar characteristics of both aNSC grafts after in vitro expansion with equal capacities of terminal differentiation into astrocytes and Tuj1+ neurons. Upon the allogenic transplantation of the respective aNSCs into the DG, PVRMB grafts showed a significantly lower graft survival and proliferative capacity compared to PVRV-SVZ transplants, whereby the latter are exclusively capable of generating new neurons. Although these differences might be-in part-related to the transplantation procedure and the short-term study design, our data strongly imply important cell-intrinsic differences between aNSCs from neurogenic compared to non-neurogenic PVRs with respect to their neurogenic potential and/or their sensitivity to neurogenic cues.
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Affiliation(s)
- Mareike Fauser
- Department of Neurology, University of Rostock, Gehlsheimer Straße 20, 18147 Rostock, Germany;
- Division of Neurodegenerative Diseases, Department of Neurology, Technische Universität Dresden, Fetscherstraße 74, 01307 Dresden, Germany; (K.F.L.); (J.R.); (M.D.B.); (A.H.)
| | - Kai F Loewenbrück
- Division of Neurodegenerative Diseases, Department of Neurology, Technische Universität Dresden, Fetscherstraße 74, 01307 Dresden, Germany; (K.F.L.); (J.R.); (M.D.B.); (A.H.)
- German Center for Neurodegenerative Diseases (DZNE), Tatzberg 41, 01307 Dresden, Germany
| | - Johannes Rangnick
- Division of Neurodegenerative Diseases, Department of Neurology, Technische Universität Dresden, Fetscherstraße 74, 01307 Dresden, Germany; (K.F.L.); (J.R.); (M.D.B.); (A.H.)
| | - Moritz D Brandt
- Division of Neurodegenerative Diseases, Department of Neurology, Technische Universität Dresden, Fetscherstraße 74, 01307 Dresden, Germany; (K.F.L.); (J.R.); (M.D.B.); (A.H.)
- German Center for Neurodegenerative Diseases (DZNE), Tatzberg 41, 01307 Dresden, Germany
| | - Andreas Hermann
- Division of Neurodegenerative Diseases, Department of Neurology, Technische Universität Dresden, Fetscherstraße 74, 01307 Dresden, Germany; (K.F.L.); (J.R.); (M.D.B.); (A.H.)
- Translational Neurodegeneration Section, “Albrecht-Kossel”, Department of Neurology, University of Rostock, Gehlsheimer Straße 20, 18147 Rostock, Germany
- German Centre for Neurodegenerative Diseases (DZNE) Rostock-Greifswald, Gehlsheimer Straße 20, 18147 Rostock, Germany
| | - Alexander Storch
- Department of Neurology, University of Rostock, Gehlsheimer Straße 20, 18147 Rostock, Germany;
- German Centre for Neurodegenerative Diseases (DZNE) Rostock-Greifswald, Gehlsheimer Straße 20, 18147 Rostock, Germany
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23
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Melbourne JK, Chandler CM, Van Doorn CE, Bardo MT, Pauly JR, Peng H, Nixon K. Primed for addiction: A critical review of the role of microglia in the neurodevelopmental consequences of adolescent alcohol drinking. Alcohol Clin Exp Res 2021; 45:1908-1926. [PMID: 34486128 PMCID: PMC8793635 DOI: 10.1111/acer.14694] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 07/22/2021] [Accepted: 08/03/2021] [Indexed: 12/15/2022]
Abstract
Alcohol is one of the most widely used recreational substances worldwide, with drinking frequently initiated during adolescence. The developmental state of the adolescent brain makes it vulnerable to initiating alcohol use, often in high doses, and particularly susceptible to alcohol-induced brain changes. Microglia, the brain parenchymal macrophages, have been implicated in mediating some of these effects, though the role that these cells play in the progression from alcohol drinking to dependence remains unclear. Microglia are uniquely positioned to sense and respond to central nervous system insult, and are now understood to exhibit innate immune memory, or "priming," altering their future functional responses based on prior exposures. In alcohol use disorders (AUDs), the role of microglia is debated. Whereas microglial activation can be pathogenic, contributing to neuroinflammation, tissue damage, and behavioral changes, or protective, it can also engage protective functions, providing support and mediating the resolution of damage. Understanding the role of microglia in adolescent AUDs is complicated by the fact that microglia are thought to be involved in developmental processes such as synaptic refinement and myelination, which underlie the functional maturation of multiple brain systems in adolescence. Thus, the role microglia play in the impact of alcohol use in adolescence is likely multifaceted. Long-term sequelae may be due to a failure to recover from EtOH-induced tissue damage, altered neurodevelopmental trajectories, and/or persistent changes to microglial responsivity and function. Here, we review critically the literature surrounding the effects of alcohol on microglia in models of adolescent alcohol misuse. We attempt to disentangle what is known about microglia from other neuroimmune effectors, to which we apply recent discoveries on the role of microglia in development and plasticity. Considered altogether, these studies challenge assumptions that proinflammatory microglia drive addiction. Alcohol priming microglia and thereby perturbing their homeostatic roles in neurodevelopment, especially during critical periods of plasticity such as adolescence, may have more serious implications for the neuropathogenesis of AUDs in adolescents.
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Affiliation(s)
- Jennifer K. Melbourne
- Division of Pharmacology and Toxicology, College of Pharmacy, The University of Texas at Austin, Austin, Texas, USA
| | - Cassie M. Chandler
- Department of Psychology, University of Kentucky, Lexington, Kentucky, USA
| | | | - Michael T. Bardo
- Department of Psychology, University of Kentucky, Lexington, Kentucky, USA
| | - James R. Pauly
- Department of Pharmaceutical Sciences, University of Kentucky, Lexington, Kentucky, USA
| | - Hui Peng
- Department of Pharmaceutical Sciences, University of Kentucky, Lexington, Kentucky, USA
| | - Kimberly Nixon
- Division of Pharmacology and Toxicology, College of Pharmacy, The University of Texas at Austin, Austin, Texas, USA
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24
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Petrella C, Strimpakos G, Torcinaro A, Middei S, Ricci V, Gargari G, Mora D, De Santa F, Farioli-Vecchioli S. Proneurogenic and neuroprotective effect of a multi strain probiotic mixture in a mouse model of acute inflammation: Involvement of the gut-brain axis. Pharmacol Res 2021; 172:105795. [PMID: 34339837 DOI: 10.1016/j.phrs.2021.105795] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 07/20/2021] [Accepted: 07/27/2021] [Indexed: 12/31/2022]
Abstract
Neuroinflammation can severely affect brain homeostasis and adult hippocampal neurogenesis with detrimental effects on cognitive processes. Brain and gut are intimately connected via the "gut-brain axis", a bidirectional communication system, and the administration of live bacteria (probiotics) has been shown to represent an intriguing approach for the prevention or even the cure of several diseases. In the present study we evaluated the putative neuroprotective effect of 15-days consumption of a multi-strain probiotic formulation based on food-associated strains and human gut bacteria at the dose of 109 CFU/mouse/day in a mouse model of acute inflammation, induced by an intraperitoneal single injection of LPS (0.1 mg/kg) at the end of probiotic administration. The results indicate that the prolonged administration of the multi-strain probiotic formulation not only prevents the LPS-dependent increase of pro-inflammatory cytokines in specific regions of the brain (hippocampus and cortex) and in the gastrointestinal district but also triggers a potent proneurogenic response capable of enhancing hippocampal neurogenesis. This effect is accompanied by a potentiation of intestinal barrier, as documented by the increased epithelial junction expression in the colon. Our hypothesis is that pre-treatment with the multi-strain probiotic formulation helps to create a systemic protection able to counteract or alleviate the effects of LPS-dependent acute pro-inflammatory responses.
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Affiliation(s)
- Carla Petrella
- Institute of Biochemistry and Cell Biology, IBBC, CNR, Policlinico Umberto I, Rome, Italy
| | - Georgios Strimpakos
- Institute of Biochemistry and Cell Biology, IBBC, CNR, Monterotondo, Rome, Italy
| | - Alessio Torcinaro
- Institute of Biochemistry and Cell Biology, IBBC, CNR, Monterotondo, Rome, Italy
| | - Silvia Middei
- Institute of Biochemistry and Cell Biology, IBBC, CNR, Monterotondo, Rome, Italy; European Brain Research Institute (EBRI), Rome, Italy
| | - Valentina Ricci
- Institute of Biochemistry and Cell Biology, IBBC, CNR, Monterotondo, Rome, Italy
| | - Giorgio Gargari
- Department of Food Environmental and Nutritional Sciences (DeFENS), University of Milan, Milan, Italy
| | - Diego Mora
- Department of Food Environmental and Nutritional Sciences (DeFENS), University of Milan, Milan, Italy
| | - Francesca De Santa
- Institute of Biochemistry and Cell Biology, IBBC, CNR, Monterotondo, Rome, Italy
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25
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Rahimian R, Wakid M, O'Leary LA, Mechawar N. The emerging tale of microglia in psychiatric disorders. Neurosci Biobehav Rev 2021; 131:1-29. [PMID: 34536460 DOI: 10.1016/j.neubiorev.2021.09.023] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 08/18/2021] [Accepted: 09/08/2021] [Indexed: 12/24/2022]
Abstract
As the professional phagocytes of the brain, microglia orchestrate the immunological response and play an increasingly important role in maintaining homeostatic brain functions. Microglia are activated by pathological events or slight alterations in brain homeostasis. This activation is dependent on the context and type of stressor or pathology. Through secretion of cytokines, chemokines and growth factors, microglia can strongly influence the response to a stressor and can, therefore, determine the pathological outcome. Psychopathologies have repeatedly been associated with long-lasting priming and sensitization of cerebral microglia. This review focuses on the diversity of microglial phenotype and function in health and psychiatric disease. We first discuss the diverse homeostatic functions performed by microglia and then elaborate on context-specific spatial and temporal microglial heterogeneity. Subsequently, we summarize microglia involvement in psychopathologies, namely major depressive disorder, schizophrenia and bipolar disorder, with a particular focus on post-mortem studies. Finally, we postulate microglia as a promising novel therapeutic target in psychiatry through antidepressant and antipsychotic treatment.
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Affiliation(s)
- Reza Rahimian
- McGill Group for Suicide Studies, Douglas Mental Health University Institute, Verdun, QC, Canada
| | - Marina Wakid
- McGill Group for Suicide Studies, Douglas Mental Health University Institute, Verdun, QC, Canada; Integrated Program in Neuroscience, McGill University, Montreal, QC, Canada
| | - Liam Anuj O'Leary
- McGill Group for Suicide Studies, Douglas Mental Health University Institute, Verdun, QC, Canada; Integrated Program in Neuroscience, McGill University, Montreal, QC, Canada
| | - Naguib Mechawar
- McGill Group for Suicide Studies, Douglas Mental Health University Institute, Verdun, QC, Canada; Integrated Program in Neuroscience, McGill University, Montreal, QC, Canada; Department of Psychiatry, McGill University, Montreal, QC, Canada.
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26
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Leschik J, Lutz B, Gentile A. Stress-Related Dysfunction of Adult Hippocampal Neurogenesis-An Attempt for Understanding Resilience? Int J Mol Sci 2021; 22:7339. [PMID: 34298958 PMCID: PMC8305135 DOI: 10.3390/ijms22147339] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 07/02/2021] [Accepted: 07/05/2021] [Indexed: 12/16/2022] Open
Abstract
Newborn neurons in the adult hippocampus are regulated by many intrinsic and extrinsic cues. It is well accepted that elevated glucocorticoid levels lead to downregulation of adult neurogenesis, which this review discusses as one reason why psychiatric diseases, such as major depression, develop after long-term stress exposure. In reverse, adult neurogenesis has been suggested to protect against stress-induced major depression, and hence, could serve as a resilience mechanism. In this review, we will summarize current knowledge about the functional relation of adult neurogenesis and stress in health and disease. A special focus will lie on the mechanisms underlying the cascades of events from prolonged high glucocorticoid concentrations to reduced numbers of newborn neurons. In addition to neurotransmitter and neurotrophic factor dysregulation, these mechanisms include immunomodulatory pathways, as well as microbiota changes influencing the gut-brain axis. Finally, we discuss recent findings delineating the role of adult neurogenesis in stress resilience.
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Affiliation(s)
- Julia Leschik
- Institute of Physiological Chemistry, University Medical Center of the Johannes Gutenberg University Mainz, 55128 Mainz, Germany;
| | - Beat Lutz
- Institute of Physiological Chemistry, University Medical Center of the Johannes Gutenberg University Mainz, 55128 Mainz, Germany;
- Leibniz Institute for Resilience Research (LIR), 55122 Mainz, Germany
| | - Antonietta Gentile
- Synaptic Immunopathology Lab, IRCCS San Raffaele Pisana, 00166 Rome, Italy;
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27
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Beecher K, Wang J, Jacques A, Chaaya N, Chehrehasa F, Belmer A, Bartlett SE. Sucrose Consumption Alters Serotonin/Glutamate Co-localisation Within the Prefrontal Cortex and Hippocampus of Mice. Front Mol Neurosci 2021; 14:678267. [PMID: 34262435 PMCID: PMC8273284 DOI: 10.3389/fnmol.2021.678267] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 06/08/2021] [Indexed: 01/23/2023] Open
Abstract
The overconsumption of sugar-sweetened food and beverages underpins the current rise in obesity rates. Sugar overconsumption induces maladaptive neuroplasticity to decrease dietary control. Although serotonin and glutamate co-localisation has been implicated in reward processing, it is still unknown how chronic sucrose consumption changes this transmission in regions associated with executive control over feeding—such as the prefrontal cortex (PFC) and dentate gyrus (DG) of the hippocampus. To address this, a total of 16 C57Bl6 mice received either 5% w/v sucrose or water as a control for 12 weeks using the Drinking-In-The-Dark paradigm (n = 8 mice per group). We then examined the effects of chronic sucrose consumption on the immunological distribution of serotonin (5-HT), vesicular glutamate transporter 3 (VGLUT3) and 5-HT+/VGLUT3+ co-localised axonal varicosities. Sucrose consumption over 12 weeks decreased the number of 5-HT–/VGLUT3+ and 5-HT+/VGLUT3+ varicosities within the PFC and DG. The number of 5-HT+/VGLUT3– varicosities remained unchanged within the PFC but decreased in the DG following sucrose consumption. Given that serotonin mediates DG neurogenesis through microglial migration, the number of microglia within the DG was also assessed in both experimental groups. Sucrose consumption decreased the number of DG microglia. Although the DG and PFC are associated with executive control over rewarding activities and emotional memory formation, we did not detect a subsequent change in DG neurogenesis or anxiety-like behaviour or depressive-like behaviour. Overall, these findings suggest that the chronic consumption of sugar alters serotonergic neuroplasticity within neural circuits responsible for feeding control. Although these alterations alone were not sufficient to induce changes in neurogenesis or behaviour, it is proposed that the sucrose consumption may predispose individuals to these cognitive deficits which ultimately promote further sugar intake.
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Affiliation(s)
- Kate Beecher
- Addiction Neuroscience and Obesity Laboratory, Faculty of Health, School of Clinical Sciences, Translational Research Institute, Queensland University of Technology, Brisbane, QLD, Australia
| | - Joshua Wang
- Addiction Neuroscience and Obesity Laboratory, Faculty of Health, School of Clinical Sciences, Translational Research Institute, Queensland University of Technology, Brisbane, QLD, Australia
| | - Angela Jacques
- Addiction Neuroscience and Obesity Laboratory, Faculty of Health, School of Clinical Sciences, Translational Research Institute, Queensland University of Technology, Brisbane, QLD, Australia
| | - Nicholas Chaaya
- Addiction Neuroscience and Obesity Laboratory, Faculty of Health, School of Clinical Sciences, Translational Research Institute, Queensland University of Technology, Brisbane, QLD, Australia
| | - Fatemeh Chehrehasa
- Addiction Neuroscience and Obesity Laboratory, Faculty of Health, School of Biomedical Sciences, Translational Research Institute, Queensland University of Technology, Brisbane, QLD, Australia
| | - Arnauld Belmer
- Addiction Neuroscience and Obesity Laboratory, Faculty of Health, School of Clinical Sciences, Translational Research Institute, Queensland University of Technology, Brisbane, QLD, Australia
| | - Selena E Bartlett
- Addiction Neuroscience and Obesity Laboratory, Faculty of Health, School of Clinical Sciences, Translational Research Institute, Queensland University of Technology, Brisbane, QLD, Australia
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28
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The interplay of neurovasculature and adult hippocampal neurogenesis. Neurosci Lett 2021; 760:136071. [PMID: 34147540 DOI: 10.1016/j.neulet.2021.136071] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 05/06/2021] [Accepted: 06/15/2021] [Indexed: 01/14/2023]
Abstract
The subgranular zone of the dentate gyrus provides a local microenvironment (niche) for neural stem cells. In the adult brain, it has been established that the vascular compartment of such niches has a significant role in regulating adult hippocampal neurogenesis. More recently, evidence showed that neurovascular coupling, the relationship between blood flow and neuronal activity, also regulates hippocampal neurogenesis. Here, we review the most recent articles on addressing the intricate relationship between neurovasculature and adult hippocampal neurogenesis and a novel pathway where functional hyperemia enhances hippocampal neurogenesis. In the end, we have further reviewed recent research showing that impaired neurovascular coupling may cause declined neurogenesis and contribute to brain damage in neurodegenerative diseases.
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29
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The Participation of Microglia in Neurogenesis: A Review. Brain Sci 2021; 11:brainsci11050658. [PMID: 34070012 PMCID: PMC8157831 DOI: 10.3390/brainsci11050658] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Revised: 05/12/2021] [Accepted: 05/15/2021] [Indexed: 01/17/2023] Open
Abstract
Adult neurogenesis was one of the most important discoveries of the last century, helping us to better understand brain function. Researchers recently discovered that microglia play an important role in this process. However, various questions remain concerning where, at what stage, and what types of microglia participate. In this review, we demonstrate that certain pools of microglia are determinant cells in different phases of the generation of new neurons. This sheds light on how cells cooperate in order to fine tune brain organization. It also provides us with a better understanding of distinct neuronal pathologies.
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30
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Dixon MA, Greferath U, Fletcher EL, Jobling AI. The Contribution of Microglia to the Development and Maturation of the Visual System. Front Cell Neurosci 2021; 15:659843. [PMID: 33967697 PMCID: PMC8102829 DOI: 10.3389/fncel.2021.659843] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 03/29/2021] [Indexed: 12/20/2022] Open
Abstract
Microglia, the resident immune cells of the central nervous system (CNS), were once considered quiescent cells that sat in readiness for reacting to disease and injury. Over the last decade, however, it has become clear that microglia play essential roles in maintaining the normal nervous system. The retina is an easily accessible part of the central nervous system and therefore much has been learned about the function of microglia from studies in the retina and visual system. Anatomically, microglia have processes that contact all synapses within the retina, as well as blood vessels in the major vascular plexuses. Microglia contribute to development of the visual system by contributing to neurogenesis, maturation of cone photoreceptors, as well as refining synaptic contacts. They can respond to neural signals and in turn release a range of cytokines and neurotrophic factors that have downstream consequences on neural function. Moreover, in light of their extensive contact with blood vessels, they are also essential for regulation of vascular development and integrity. This review article summarizes what we have learned about the role of microglia in maintaining the normal visual system and how this has helped in understanding their role in the central nervous system more broadly.
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Affiliation(s)
- Michael A Dixon
- Department of Anatomy and Physiology, The University of Melbourne, Melbourne, VIC, Australia
| | - Ursula Greferath
- Department of Anatomy and Physiology, The University of Melbourne, Melbourne, VIC, Australia
| | - Erica L Fletcher
- Department of Anatomy and Physiology, The University of Melbourne, Melbourne, VIC, Australia
| | - Andrew I Jobling
- Department of Anatomy and Physiology, The University of Melbourne, Melbourne, VIC, Australia
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31
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Gampierakis IA, Koutmani Y, Semitekolou M, Morianos I, Polissidis A, Katsouda A, Charalampopoulos I, Xanthou G, Gravanis A, Karalis KP. Hippocampal neural stem cells and microglia response to experimental inflammatory bowel disease (IBD). Mol Psychiatry 2021; 26:1248-1263. [PMID: 31969694 DOI: 10.1038/s41380-020-0651-6] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 11/26/2019] [Accepted: 11/26/2019] [Indexed: 12/20/2022]
Abstract
Inflammatory bowel disease (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), is a disease associated with dysbiosis, resulting in compromised intestinal epithelial barrier and chronic mucosal inflammation. Patients with IBD present with increased incidence of psychiatric disorders and cognitive impairment. Hippocampus is a brain region where adult neurogenesis occurs with functional implications in mood control and cognition. Using a well-established model of experimental colitis based on the administration of dextran sodium sulfate (DSS) in the drinking water, we sought to characterize the short and long-term effects of colitis on neurogenesis and glia responses in the hippocampus. We show that acute DSS colitis enhanced neurogenesis but with deficits in cell cycle kinetics of proliferating progenitors in the hippocampus. Chronic DSS colitis was characterized by normal levels of neurogenesis but with deficits in the migration and integration of newborn neurons in the functional circuitry of the DG. Notably, we found that acute DSS colitis-induced enhanced infiltration of the hippocampus with macrophages and inflammatory myeloid cells from the periphery, along with elevated frequencies of inflammatory M1-like microglia and increased release of pro-inflammatory cytokines. In contrast, increased percentages of tissue-repairing M2-like microglia, along with elevated levels of the anti-inflammatory cytokine, IL-10 were observed in the hippocampus during chronic DSS colitis. These findings uncover key effects of acute and chronic experimental colitis on adult hippocampal neurogenesis and innate immune cell responses, highlighting the potential mechanisms underlying cognitive and mood dysfunction in patients with IBD.
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Affiliation(s)
- Ioannis-Alexandros Gampierakis
- Center for Experimental Surgery, Clinical and Translational Research, Biomedical Research Foundation of the Academy of Athens, Athens, Greece
- Department of Pharmacology, School of Medicine, University of Crete, Heraklion, Greece
| | - Yassemi Koutmani
- Center for Experimental Surgery, Clinical and Translational Research, Biomedical Research Foundation of the Academy of Athens, Athens, Greece
| | - Maria Semitekolou
- Cellular Immunology Laboratory, Center for Basic Research, Biomedical Research Foundation of the Academy of Athens, Athens, Greece
| | - Ioannis Morianos
- Cellular Immunology Laboratory, Center for Basic Research, Biomedical Research Foundation of the Academy of Athens, Athens, Greece
| | - Alexia Polissidis
- Center for Experimental Surgery, Clinical and Translational Research, Biomedical Research Foundation of the Academy of Athens, Athens, Greece
| | - Antonia Katsouda
- Center for Experimental Surgery, Clinical and Translational Research, Biomedical Research Foundation of the Academy of Athens, Athens, Greece
- School of Pharmacy, University of Athens, Athens, Greece
| | - Ioannis Charalampopoulos
- Department of Pharmacology, School of Medicine, University of Crete, Heraklion, Greece
- Institute of Molecular Biology & Biotechnology (IMBB), Foundation of Research & Technology Hellas (FORTH), Heraklion, Greece
| | - Georgina Xanthou
- Cellular Immunology Laboratory, Center for Basic Research, Biomedical Research Foundation of the Academy of Athens, Athens, Greece
| | - Achille Gravanis
- Department of Pharmacology, School of Medicine, University of Crete, Heraklion, Greece
- Institute of Molecular Biology & Biotechnology (IMBB), Foundation of Research & Technology Hellas (FORTH), Heraklion, Greece
| | - Katia P Karalis
- Center for Experimental Surgery, Clinical and Translational Research, Biomedical Research Foundation of the Academy of Athens, Athens, Greece.
- Emulate, Inc., 27 Drydock Avenue, Boston, MA, 02210, USA.
- Endocrine Division, Children's Hospital, Harvard Medical School, Boston, MA, USA.
- Institute for Fundamental Biomedical Research, Biomedical Science Research Centre "Alexander Fleming", Athens, Greece.
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32
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Han J, Fan Y, Zhou K, Blomgren K, Harris RA. Uncovering sex differences of rodent microglia. J Neuroinflammation 2021; 18:74. [PMID: 33731174 PMCID: PMC7972194 DOI: 10.1186/s12974-021-02124-z] [Citation(s) in RCA: 72] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Accepted: 03/05/2021] [Indexed: 12/11/2022] Open
Abstract
There are inherent structural and functional differences in the central nervous systems (CNS) of females and males. It has been gradually established that these sex-specific differences are due to a spectrum of genetic, epigenetic, and hormonal factors which actively contribute to the differential incidences, disease courses, and even outcomes of CNS diseases between sexes. Microglia, as principle resident macrophages in the CNS, play a crucial role in both CNS physiology and pathology. However, sex differences of microglia have been relatively unexplored until recently. Emerging data has convincingly demonstrated the existence of sex-dependent structural and functional differences of rodent microglia, consequently changing our current understanding of these versatile cells. In this review, we attempt to comprehensively outline the current advances revealing microglial sex differences in rodent and their potential implications for specific CNS diseases with a stark sex difference. A detailed understanding of molecular processes underlying microglial sex differences is of major importance in design of translational sex- and microglia-specific therapeutic approaches.
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Affiliation(s)
- Jinming Han
- Applied Immunology and Immunotherapy, Department of Clinical Neuroscience, Karolinska Institutet, Center for Molecular Medicine, Karolinska University Hospital, CMM L8:04, Karolinska Sjukhuset, S-171 76, Stockholm, Sweden.
| | - Yueshan Fan
- Applied Immunology and Immunotherapy, Department of Clinical Neuroscience, Karolinska Institutet, Center for Molecular Medicine, Karolinska University Hospital, CMM L8:04, Karolinska Sjukhuset, S-171 76, Stockholm, Sweden.,Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, China.,Key Laboratory of Injuries, Variations and Regeneration of Nervous System, Tianjin Neurological Institute, Tianjin, China.,Tianjin Medical University, Tianjin, China
| | - Kai Zhou
- Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden.,Department of Pediatrics, Children's Hospital of Zhengzhou, Zhengzhou, China
| | - Klas Blomgren
- Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden.,Pediatric Oncology, Karolinska University Hospital, Stockholm, Sweden
| | - Robert A Harris
- Applied Immunology and Immunotherapy, Department of Clinical Neuroscience, Karolinska Institutet, Center for Molecular Medicine, Karolinska University Hospital, CMM L8:04, Karolinska Sjukhuset, S-171 76, Stockholm, Sweden.
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Chintamen S, Imessadouene F, Kernie SG. Immune Regulation of Adult Neurogenic Niches in Health and Disease. Front Cell Neurosci 2021; 14:571071. [PMID: 33551746 PMCID: PMC7855589 DOI: 10.3389/fncel.2020.571071] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 12/23/2020] [Indexed: 12/18/2022] Open
Abstract
Microglia regulate neuronal development during embryogenesis, postnatal development, and in specialized microenvironments of the adult brain. Recent evidence demonstrates that in adulthood, microglia secrete factors which modulate adult hippocampal neurogenesis by inhibiting cell proliferation and survival both in vitro and in vivo, maintaining a balance between cell division and cell death in neurogenic niches. These resident immune cells also shape the nervous system by actively pruning synapses during critical periods of learning and engulfing excess neurons. In neurodegenerative diseases, aberrant microglial activity can impede the proper formation and prevent the development of appropriate functional properties of adult born granule cells. Ablating microglia has been presented as a promising therapeutic approach to alleviate the brain of maladaptive immune response. Here, we review key mechanisms through which the immune system actively shapes neurogenic niches throughout the lifespan of the mammalian brain in both health and disease. We discuss how interactions between immune cells and developing neurons may be leveraged for pharmacological intervention and as a means to preserve adult neurogenesis.
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Affiliation(s)
- Sana Chintamen
- Neurobiology and Behavior, Columbia University Irving Medical Center, New York, NY, United States.,Department of Pediatrics, Columbia University Irving Fefere Medical Center, New York, NY, United States
| | - Fatima Imessadouene
- Department of Pediatrics, Columbia University Irving Fefere Medical Center, New York, NY, United States
| | - Steven G Kernie
- Department of Pediatrics, Columbia University Irving Fefere Medical Center, New York, NY, United States
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Du Preez A, Onorato D, Eiben I, Musaelyan K, Egeland M, Zunszain PA, Fernandes C, Thuret S, Pariante CM. Chronic stress followed by social isolation promotes depressive-like behaviour, alters microglial and astrocyte biology and reduces hippocampal neurogenesis in male mice. Brain Behav Immun 2021; 91:24-47. [PMID: 32755644 DOI: 10.1016/j.bbi.2020.07.015] [Citation(s) in RCA: 110] [Impact Index Per Article: 36.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 06/29/2020] [Accepted: 07/11/2020] [Indexed: 12/11/2022] Open
Abstract
Unpredictable chronic mild stress (UCMS) is one of the most commonly used, robust and translatable models for studying the neurobiological basis of major depression. Although the model currently has multiple advantages, it does not entirely follow the trajectory of the disorder, whereby depressive symptomology can often present months after exposure to stress. Furthermore, patients with depression are more likely to withdraw in response to their stressful experience, or as a symptom of their depression, and, in turn, this withdrawal/isolation can further exacerbate the stressful experience and the depressive symptomology. Therefore, we investigated the effect(s) of 6 weeks of UCMS followed by another 6 weeks of social isolation (referred to as UCMSI), on behaviour, corticosterone stress responsivity, immune system functioning, and hippocampal neurogenesis, in young adult male mice. We found that UCMSI induced several behavioural changes resembling depression but did not induce peripheral inflammation. However, UCMSI animals showed increased microglial activation in the ventral dentate gyrus (DG) of the hippocampus and astrocyte activation in both the dorsal and ventral DG, with increased GFAP-positive cell immunoreactivity, GFAP-positive cell hypertrophy and process extension, and increased s100β-positive cell density. Moreover, UCMSI animals had significantly reduced neurogenesis in the DG and reduced levels of peripheral vascular endothelial growth factor (VEGF) - a trophic factor produced by astrocytes and that stimulates neurogenesis. Finally, UCMSI mice also had normal baseline corticosterone levels but a smaller increase in corticosterone following acute stress, that is, the Porsolt Swim Test. Our work gives clinically relevant insights into the role that microglial and astrocyte functioning, and hippocampal neurogenesis may play in the context of stress, social isolation and depression, offering a potentially new avenue for therapeutic target.
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Affiliation(s)
- Andrea Du Preez
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology & Neuroscience, King's College London, UK.
| | - Diletta Onorato
- Department of Psychological Medicine, Institute of Psychiatry, Psychology & Neuroscience, King's College London, UK
| | - Inez Eiben
- Department of Psychological Medicine, Institute of Psychiatry, Psychology & Neuroscience, King's College London, UK
| | - Ksenia Musaelyan
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology & Neuroscience, King's College London, UK
| | - Martin Egeland
- Department of Psychological Medicine, Institute of Psychiatry, Psychology & Neuroscience, King's College London, UK
| | - Patricia A Zunszain
- Department of Psychological Medicine, Institute of Psychiatry, Psychology & Neuroscience, King's College London, UK
| | - Cathy Fernandes
- Social, Genetic & Developmental Psychiatry Centre, Institute of Psychiatry, Psychology & Neuroscience, King's College London, UK; MRC Centre for Neurodevelopmental Disorders, Institute of Psychiatry, Psychology & Neuroscience, King's College London, UK
| | - Sandrine Thuret
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology & Neuroscience, King's College London, UK
| | - Carmine M Pariante
- Department of Psychological Medicine, Institute of Psychiatry, Psychology & Neuroscience, King's College London, UK
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Du Preez A, Law T, Onorato D, Lim YM, Eiben P, Musaelyan K, Egeland M, Hye A, Zunszain PA, Thuret S, Pariante CM, Fernandes C. The type of stress matters: repeated injection and permanent social isolation stress in male mice have a differential effect on anxiety- and depressive-like behaviours, and associated biological alterations. Transl Psychiatry 2020; 10:325. [PMID: 32958745 PMCID: PMC7505042 DOI: 10.1038/s41398-020-01000-3] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 08/12/2020] [Accepted: 09/03/2020] [Indexed: 01/02/2023] Open
Abstract
Chronic stress can alter the immune system, adult hippocampal neurogenesis and induce anxiety- and depressive-like behaviour in rodents. However, previous studies have not discriminated between the effect(s) of different types of stress on these behavioural and biological outcomes. We investigated the effect(s) of repeated injection vs. permanent social isolation on behaviour, stress responsivity, immune system functioning and hippocampal neurogenesis, in young adult male mice, and found that the type of stress exposure does indeed matter. Exposure to 6 weeks of repeated injection resulted in an anxiety-like phenotype, decreased systemic inflammation (i.e., reduced plasma levels of TNFα and IL4), increased corticosterone reactivity, increased microglial activation and decreased neuronal differentiation in the dentate gyrus (DG). In contrast, exposure to 6 weeks of permanent social isolation resulted in a depressive-like phenotype, increased plasma levels of TNFα, decreased plasma levels of IL10 and VEGF, decreased corticosterone reactivity, decreased microglial cell density and increased cell density for radial glia, s100β-positive cells and mature neuroblasts-all in the DG. Interestingly, combining the two distinct stress paradigms did not have an additive effect on behavioural and biological outcomes, but resulted in yet a different phenotype, characterized by increased anxiety-like behaviour, decreased plasma levels of IL1β, IL4 and VEGF, and decreased hippocampal neuronal differentiation, without altered neuroinflammation or corticosterone reactivity. These findings demonstrate that different forms of chronic stress can differentially alter both behavioural and biological outcomes in young adult male mice, and that combining multiple stressors may not necessarily cause more severe pathological outcomes.
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Affiliation(s)
- Andrea Du Preez
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Thomas Law
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Diletta Onorato
- Department of Psychological Medicine, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Yau M Lim
- Department of Old Age Psychiatry, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Paola Eiben
- Department of Psychological Medicine, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Ksenia Musaelyan
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Martin Egeland
- Department of Psychological Medicine, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Abdul Hye
- Department of Old Age Psychiatry, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Patricia A Zunszain
- Department of Psychological Medicine, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Sandrine Thuret
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Carmine M Pariante
- Department of Psychological Medicine, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK
| | - Cathy Fernandes
- Social, Genetic & Developmental Psychiatry Centre, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK.
- MRC Centre for Neurodevelopmental Disorders, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK.
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36
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Araki T, Ikegaya Y, Koyama R. The effects of microglia‐ and astrocyte‐derived factors on neurogenesis in health and disease. Eur J Neurosci 2020; 54:5880-5901. [PMID: 32920880 PMCID: PMC8451940 DOI: 10.1111/ejn.14969] [Citation(s) in RCA: 82] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 09/01/2020] [Accepted: 09/02/2020] [Indexed: 12/20/2022]
Abstract
Hippocampal neurogenesis continues throughout life and has been suggested to play an essential role in maintaining spatial cognitive function under physiological conditions. An increasing amount of evidence has indicated that adult neurogenesis is tightly controlled by environmental conditions in the neurogenic niche, which consists of multiple types of cells including microglia and astrocytes. Microglia maintain the environment of neurogenic niche through their phagocytic capacity and interaction with neurons via fractalkine‐CX3CR1 signaling. In addition, microglia release growth factors such as brain‐derived neurotrophic factor (BDNF) and cytokines such as tumor necrosis factor (TNF)‐α to support the development of adult born neurons. Astrocytes also manipulate neurogenesis by releasing various soluble factors including adenosine triphosphate and lactate. Whereas, under pathological conditions such as Alzheimer's disease, depression, and epilepsy, microglia and astrocytes play a leading role in inflammation and are involved in attenuating the normal process of neurogenesis. The modulation of glial functions on neurogenesis in these brain diseases are attracting attention as a new therapeutic target. This review describes how these glial cells play a role in adult hippocampal neurogenesis in both health and disease, especially focusing glia‐derived factors.
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Affiliation(s)
- Tasuku Araki
- Laboratory of Chemical Pharmacology Graduate School of Pharmaceutical Sciences The University of Tokyo Tokyo Japan
| | - Yuji Ikegaya
- Laboratory of Chemical Pharmacology Graduate School of Pharmaceutical Sciences The University of Tokyo Tokyo Japan
- Center for Information and Neural Networks Suita City Osaka Japan
| | - Ryuta Koyama
- Laboratory of Chemical Pharmacology Graduate School of Pharmaceutical Sciences The University of Tokyo Tokyo Japan
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Kol A, Adamsky A, Groysman M, Kreisel T, London M, Goshen I. Astrocytes contribute to remote memory formation by modulating hippocampal-cortical communication during learning. Nat Neurosci 2020; 23:1229-1239. [PMID: 32747787 PMCID: PMC7611962 DOI: 10.1038/s41593-020-0679-6] [Citation(s) in RCA: 147] [Impact Index Per Article: 36.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2019] [Accepted: 06/26/2020] [Indexed: 12/15/2022]
Abstract
Remote memories depend on coordinated activity in the hippocampus and frontal cortices, but the timeline of these interactions is debated. Astrocytes sense and modify neuronal activity, but their role in remote memory was scarcely explored. We expressed the Gi-coupled receptor hM4Di in CA1 astrocytes, and discovered that astrocytic manipulation during learning specifically impaired remote, but not recent, memory recall, and decreased activity in the anterior cingulate cortex (ACC) during retrieval. We revealed massive recruitment of ACC-projecting CA1 neurons during memory acquisition, accompanied by activation of ACC neurons. Astrocytic Gi activation disrupted CA3 to CA1 communication in-vivo, and reduced the downstream response in ACC. In behaving mice, it induced a projection-specific inhibition of CA1-to-ACC neurons during learning, consequently preventing ACC recruitment. Finally, direct inhibition of CA1-to-ACC projecting neurons spared recent and impaired remote memory. Our findings suggest that remote memory acquisition involves projection-specific functions of astrocytes in regulating CA1-to-ACC neuronal communication.
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Affiliation(s)
- Adi Kol
- Edmond and Lily Safra Center for Brain Sciences (ELSC), The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Adar Adamsky
- Edmond and Lily Safra Center for Brain Sciences (ELSC), The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Maya Groysman
- ELSC Vector Core Facility, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Tirzah Kreisel
- Edmond and Lily Safra Center for Brain Sciences (ELSC), The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Michael London
- Edmond and Lily Safra Center for Brain Sciences (ELSC), The Hebrew University of Jerusalem, Jerusalem, Israel.,Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Inbal Goshen
- Edmond and Lily Safra Center for Brain Sciences (ELSC), The Hebrew University of Jerusalem, Jerusalem, Israel.
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38
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Victor TR, Tsirka SE. Microglial contributions to aberrant neurogenesis and pathophysiology of epilepsy. NEUROIMMUNOLOGY AND NEUROINFLAMMATION 2020; 7:234-247. [PMID: 33154976 PMCID: PMC7641338 DOI: 10.20517/2347-8659.2020.02] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Microglia are dynamic cells that constitute the brain's innate immune system. Recently, research has demonstrated microglial roles beyond immunity, which include homeostatic roles in the central nervous system. The function of microglia is an active area of study, with insights into changes in neurogenesis and synaptic pruning being discovered in both health and disease. In epilepsy, activated microglia contribute to several changes that occur during epileptogenesis. In this review, we focus on the effects of microglia on neurogenesis and synaptic pruning, and discuss the current state of anti-seizure drugs and how they affect microglia during these processes. Our understanding of the role of microglia post-seizure is still limited and may be pivotal in recognizing new therapeutic targets for seizure intervention.
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Affiliation(s)
- Tanya R Victor
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, NY 11794, USA
| | - Stella E Tsirka
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, NY 11794, USA
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Bonafina A, Paratcha G, Ledda F. Deciphering New Players in the Neurogenic Adult Hippocampal Niche. Front Cell Dev Biol 2020; 8:548. [PMID: 32714932 PMCID: PMC7346873 DOI: 10.3389/fcell.2020.00548] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 06/10/2020] [Indexed: 12/23/2022] Open
Abstract
In the mammalian adult hippocampus, new neurons are continuously generated throughout life in the subgranular zone of the dentate gyrus. Increasing evidence point out the contribution of adult-born hippocampal granule cells (GCs) to cognitive processes such as learning and memory, indicating the relevance of understanding the molecular mechanisms that control the development of these new neurons in the preexisting hippocampal circuits. Cell proliferation and functional integration of adult-born GCs is a process highly regulated by different intrinsic and extrinsic factors. In this review, we discuss recent advances related with cellular components and extrinsic signals of the hippocampal neurogenic niche that support and modulate neurogenesis under physiological conditions.
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Affiliation(s)
- Antonela Bonafina
- División de Neurociencia Molecular y Celular, Instituto de Biología Celular y Neurociencias, Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| | - Gustavo Paratcha
- División de Neurociencia Molecular y Celular, Instituto de Biología Celular y Neurociencias, Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| | - Fernanda Ledda
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
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40
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Marsters CM, Nesan D, Far R, Klenin N, Pittman QJ, Kurrasch DM. Embryonic microglia influence developing hypothalamic glial populations. J Neuroinflammation 2020; 17:146. [PMID: 32375817 PMCID: PMC7201702 DOI: 10.1186/s12974-020-01811-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 04/13/2020] [Indexed: 11/15/2022] Open
Abstract
Background Although historically microglia were thought to be immature in the fetal brain, evidence of purposeful interactions between these immune cells and nearby neural progenitors is becoming established. Here, we examined the influence of embryonic microglia on gliogenesis within the developing tuberal hypothalamus, a region later important for energy balance, reproduction, and thermoregulation. Methods We used immunohistochemistry to quantify the location and numbers of glial cells in the embryonic brain (E13.5–E17.5), as well as a pharmacological approach (i.e., PLX5622) to knock down fetal microglia. We also conducted cytokine and chemokine analyses on embryonic brains in the presence or absence of microglia, and a neurosphere assay to test the effects of the altered cytokines on hypothalamic progenitor behaviors. Results We identified a subpopulation of activated microglia that congregated adjacent to the third ventricle alongside embryonic Olig2+ neural progenitor cells (NPCs) that are destined to give rise to oligodendrocyte and astrocyte populations. In the absence of microglia, we observed an increase in Olig2+ glial progenitor cells that remained at the ventricle by E17.5 and a concomitant decrease of these Olig2+ cells in the mantle zone, indicative of a delay in migration of these precursor cells. A further examination of maturing oligodendrocytes in the hypothalamic grey and white matter area in the absence of microglia revealed migrating oligodendrocyte progenitor cells (OPCs) within the grey matter at E17.5, a time point when OPCs begin to slow their migration. Finally, quantification of cytokine and chemokine signaling in ex vivo E15.5 hypothalamic cultures +/− microglia revealed decreases in the protein levels of several cytokines in the absence of microglia. We assayed the influence of two downregulated cytokines (CCL2 and CXCL10) on neurosphere-forming capacity and lineage commitment of hypothalamic NPCs in culture and showed an increase in NPC proliferation as well as neuronal and oligodendrocyte differentiation. Conclusion These data demonstrate that microglia influence gliogenesis in the developing tuberal hypothalamus.
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Affiliation(s)
- Candace M Marsters
- Department of Medical Genetics, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Physiology & Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
| | - Dinushan Nesan
- Department of Medical Genetics, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
| | - Rena Far
- Department of Medical Genetics, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
| | - Natalia Klenin
- Department of Medical Genetics, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
| | - Quentin J Pittman
- Department of Physiology & Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
| | - Deborah M Kurrasch
- Department of Medical Genetics, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada. .,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada. .,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada.
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41
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Communication, Cross Talk, and Signal Integration in the Adult Hippocampal Neurogenic Niche. Neuron 2020; 105:220-235. [PMID: 31972145 DOI: 10.1016/j.neuron.2019.11.029] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 11/21/2019] [Accepted: 11/25/2019] [Indexed: 12/14/2022]
Abstract
Radial glia-like neural stem cells (RGLs) in the dentate gyrus subregion of the hippocampus give rise to dentate granule cells (DGCs) and astrocytes throughout life, a process referred to as adult hippocampal neurogenesis. Adult hippocampal neurogenesis is sensitive to experiences, suggesting that it may represent an adaptive mechanism by which hippocampal circuitry is modified in response to environmental demands. Experiential information is conveyed to RGLs, progenitors, and adult-born DGCs via the neurogenic niche that is composed of diverse cell types, extracellular matrix, and afferents. Understanding how the niche performs its functions may guide strategies to maintain its health span and provide a permissive milieu for neurogenesis. Here, we first discuss representative contributions of niche cell types to regulation of neural stem cell (NSC) homeostasis and maturation of adult-born DGCs. We then consider mechanisms by which the activity of multiple niche cell types may be coordinated to communicate signals to NSCs. Finally, we speculate how NSCs integrate niche-derived signals to govern their regulation.
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Age-Dependent Remarkable Regenerative Potential of the Dentate Gyrus Provided by Intrinsic Stem Cells. J Neurosci 2020; 40:974-995. [PMID: 31959697 DOI: 10.1523/jneurosci.1010-19.2019] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2019] [Revised: 12/11/2019] [Accepted: 12/12/2019] [Indexed: 12/12/2022] Open
Abstract
Multiple insults to the brain lead to neuronal cell death, thus raising the question to what extent can lost neurons be replenished by adult neurogenesis. Here we focused on the hippocampus and especially the dentate gyrus (DG), a vulnerable brain region and one of the two sites where adult neuronal stem cells (NSCs) reside. While adult hippocampal neurogenesis was extensively studied with regard to its contribution to cognitive enhancement, we focused on their underestimated capability to repair a massively injured, nonfunctional DG. To address this issue, we inflicted substantial DG-specific damage in mice of either sex either by diphtheria toxin-based ablation of >50% of mature DG granule cells (GCs) or by prolonged brain-specific VEGF overexpression culminating in extensive, highly selective loss of DG GCs (thereby also reinforcing the notion of selective DG vulnerability). The neurogenic system promoted effective regeneration by increasing NSCs proliferation/survival rates, restoring a nearly original DG mass, promoting proper rewiring of regenerated neurons to their afferent and efferent partners, and regaining of lost spatial memory. Notably, concomitantly with the natural age-related decline in the levels of neurogenesis, the regenerative capacity of the hippocampus also subsided with age. The study thus revealed an unappreciated regenerative potential of the young DG and suggests hippocampal NSCs as a critical reservoir enabling recovery from catastrophic DG damage.SIGNIFICANCE STATEMENT Adult hippocampal neurogenesis has been extensively studied in the context of its role in cognitive enhancement, but whether, and to what extent can dentate gyrus (DG)-resident neural stem cells drive regeneration of an injured DG has remained unclear. Here we show that DG neurogenesis acts to replace lost neurons and restore lost functions even following massive (>50%) neuronal loss. Age-related decline of neurogenesis is paralleled by a progressive decline of regenerative capacity. Considering also the exceptional vulnerability of the DG to insults, these findings provide a further rationale for maintaining DG neurogenesis in adult life.
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High-Fat Diet-Induced Obesity Causes Sex-Specific Deficits in Adult Hippocampal Neurogenesis in Mice. eNeuro 2020; 7:ENEURO.0391-19.2019. [PMID: 31871124 PMCID: PMC6946541 DOI: 10.1523/eneuro.0391-19.2019] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 11/26/2019] [Accepted: 12/01/2019] [Indexed: 12/13/2022] Open
Abstract
Adult hippocampal neurogenesis (AHN) is suppressed by high-fat (HF) diet and metabolic disease, including obesity and type 2 diabetes. Deficits in AHN may contribute to cognitive decline and increased risk of dementia and mood disorders, which have higher prevalence in women. However, sex differences in the effects of HF diet/metabolic disease on AHN have yet to be thoroughly investigated. Herein, male and female C57BL/6J mice were fed an HF or control (CON) diet from ∼2 to 6 months of age. After 3 months on the diet, mice were injected with 5-ethynyl-2′-deoxyuridine (EdU) then killed 4 weeks later. Cell proliferation, differentiation/maturation, and survival of new neurons in the dentate gyrus were assessed with immunofluorescence for EdU, Ki67, doublecortin (DCX), and NeuN. CON females had more proliferating cells (Ki67+) and neuroblasts/immature neurons (DCX+) compared with CON males; however, HF diet reduced these cells in females to the levels of males. Diet did not affect neurogenesis in males. Further, the numbers of proliferating cells and immature neurons were inversely correlated with both weight gain and glucose intolerance in females only. These effects were robust in the dorsal hippocampus, which supports cognitive processes. Assessment of microglia in the dentate gyrus using immunofluorescence for Iba1 and CD68 uncovered sex-specific effects of diet, which may contribute to observed differences in neurogenesis. These findings demonstrate sex-specific effects of HF diet/metabolic disease on AHN, and highlight the potential for targeting neurogenic deficits to treat cognitive decline and reduce the risk of dementia associated with these conditions, particularly in females.
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Microglia Actively Remodel Adult Hippocampal Neurogenesis through the Phagocytosis Secretome. J Neurosci 2020; 40:1453-1482. [PMID: 31896673 PMCID: PMC7044727 DOI: 10.1523/jneurosci.0993-19.2019] [Citation(s) in RCA: 188] [Impact Index Per Article: 47.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 12/12/2019] [Accepted: 12/13/2019] [Indexed: 12/15/2022] Open
Abstract
During adult hippocampal neurogenesis, most newborn cells undergo apoptosis and are rapidly phagocytosed by resident microglia to prevent the spillover of intracellular contents. Here, we propose that phagocytosis is not merely passive corpse removal but has an active role in maintaining neurogenesis. First, we found that neurogenesis was disrupted in male and female mice chronically deficient for two phagocytosis pathways: the purinergic receptor P2Y12, and the tyrosine kinases of the TAM family Mer tyrosine kinase (MerTK)/Axl. In contrast, neurogenesis was transiently increased in mice in which MerTK expression was conditionally downregulated. Next, we performed a transcriptomic analysis of the changes induced by phagocytosis in microglia in vitro and identified genes involved in metabolism, chromatin remodeling, and neurogenesis-related functions. Finally, we discovered that the secretome of phagocytic microglia limits the production of new neurons both in vivo and in vitro Our data suggest that microglia act as a sensor of local cell death, modulating the balance between proliferation and survival in the neurogenic niche through the phagocytosis secretome, thereby supporting the long-term maintenance of adult hippocampal neurogenesis.SIGNIFICANCE STATEMENT Microglia are the brain professional phagocytes and, in the adult hippocampal neurogenic niche, they remove newborn cells naturally undergoing apoptosis. Here we show that phagocytosis of apoptotic cells triggers a coordinated transcriptional program that alters their secretome, limiting neurogenesis both in vivo and in vitro In addition, chronic phagocytosis disruption in mice deficient for receptors P2Y12 and MerTK/Axl reduces adult hippocampal neurogenesis. In contrast, inducible MerTK downregulation transiently increases neurogenesis, suggesting that microglial phagocytosis provides a negative feedback loop that is necessary for the long-term maintenance of adult hippocampal neurogenesis. Therefore, we speculate that the effects of promoting engulfment/degradation of cell debris may go beyond merely removing corpses to actively promoting regeneration in development, aging, and neurodegenerative diseases.
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Nakafuku M, Del Águila Á. Developmental dynamics of neurogenesis and gliogenesis in the postnatal mammalian brain in health and disease: Historical and future perspectives. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2019; 9:e369. [PMID: 31825170 DOI: 10.1002/wdev.369] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 09/16/2019] [Accepted: 10/22/2019] [Indexed: 12/21/2022]
Abstract
The mature mammalian brain has long been thought to be a structurally rigid, static organ since the era of Ramón y Cajal in the early 20th century. Evidence accumulated over the past three decades, however, has completely overturned this long-held view. We now know that new neurons and glia are continuously added to the brain at postnatal stages, even in mature adults of various mammalian species, including humans. Moreover, these newly added cells contribute to structural plasticity and play important roles in higher order brain function, as well as repair after damage. A major source of these new neurons and glia is neural stem cells (NSCs) that persist in specialized niches in the brain throughout life. With this new view, our understanding of normal brain physiology and interventional approaches to various brain disorders has changed markedly in recent years. This article provides a brief overview on the historical changes in our understanding of the developmental dynamics of neurogenesis and gliogenesis in the postnatal and adult mammalian brain and discusses the roles of NSCs and other progenitor populations in such cellular dynamics in health and disease of the postnatal mammalian brain. This article is categorized under: Adult Stem Cells, Tissue Renewal, and Regeneration > Stem Cell Differentiation and Reversion Adult Stem Cells, Tissue Renewal, and Regeneration > Tissue Stem Cells and Niches Adult Stem Cells, Tissue Renewal, and Regeneration > Regeneration Adult Stem Cells, Tissue Renewal, and Regeneration > Stem Cells and Disease.
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Affiliation(s)
- Masato Nakafuku
- Divisions of Developmental Biology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, Ohio.,Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Ángela Del Águila
- Divisions of Developmental Biology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, Ohio.,Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio
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What Do Microglia Really Do in Healthy Adult Brain? Cells 2019; 8:cells8101293. [PMID: 31652490 PMCID: PMC6829860 DOI: 10.3390/cells8101293] [Citation(s) in RCA: 83] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 10/17/2019] [Accepted: 10/18/2019] [Indexed: 12/27/2022] Open
Abstract
Microglia originate from yolk sac-primitive macrophages and auto-proliferate into adulthood without replacement by bone marrow-derived circulating cells. In inflammation, stroke, aging, or infection, microglia have been shown to contribute to brain pathology in both deleterious and beneficial ways, which have been studied extensively. However, less is known about their role in the healthy adult brain. Astrocytes and oligodendrocytes are widely accepted to strongly contribute to the maintenance of brain homeostasis and to modulate neuronal function. On the other hand, contribution of microglia to cognition and behavior is only beginning to be understood. The ability to probe their function has become possible using microglial depletion assays and conditional mutants. Studies have shown that the absence of microglia results in cognitive and learning deficits in rodents during development, but this effect is less pronounced in adults. However, evidence suggests that microglia play a role in cognition and learning in adulthood and, at a cellular level, may modulate adult neurogenesis. This review presents the case for repositioning microglia as key contributors to the maintenance of homeostasis and cognitive processes in the healthy adult brain, in addition to their classical role as sentinels coordinating the neuroinflammatory response to tissue damage and disease.
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Microglial P2Y12 Receptor Regulates Seizure-Induced Neurogenesis and Immature Neuronal Projections. J Neurosci 2019; 39:9453-9464. [PMID: 31597724 DOI: 10.1523/jneurosci.0487-19.2019] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2019] [Revised: 10/01/2019] [Accepted: 10/02/2019] [Indexed: 11/21/2022] Open
Abstract
Seizures are common in humans with various etiologies ranging from congenital aberrations to acute injuries that alter the normal balance of brain excitation and inhibition. A notable consequence of seizures is the induction of aberrant neurogenesis and increased immature neuronal projections. However, regulatory mechanisms governing these features during epilepsy development are not fully understood. Recent studies show that microglia, the brain's resident immune cell, contribute to normal neurogenesis and regulate seizure phenotypes. However, the role of microglia in aberrant neurogenic seizure contexts has not been adequately investigated. To address this question, we coupled the intracerebroventricular kainic acid model with current pharmacogenetic approaches to eliminate microglia in male mice. We show that microglia promote seizure-induced neurogenesis and subsequent seizure-induced immature neuronal projections above and below the pyramidal neurons between the DG and the CA3 regions. Furthermore, we identify microglial P2Y12 receptors (P2Y12R) as a participant in this neurogenic process. Together, our results implicate microglial P2Y12R signaling in epileptogenesis and provide further evidence for targeting microglia in general and microglial P2Y12R in specific to ameliorate proepileptogenic processes.SIGNIFICANCE STATEMENT Epileptogenesis is a process by which the brain develops epilepsy. Several processes have been identified that confer the brain with such epileptic characteristics, including aberrant neurogenesis and increased immature neuronal projections. Understanding the mechanisms that promote such changes is critical in developing therapies to adequately restrain epileptogenesis. We investigated the role of purinergic P2Y12 receptors selectively expressed by microglia, the resident brain immune cells. We report, for the first time, that microglia in general and microglial P2Y12 receptors in specific promote both aberrant neurogenesis and increased immature neuronal projections. These results indicate that microglia enhance epileptogenesis by promoting these processes and suggest that targeting this immune axis could be a novel therapeutic strategy in the clinic.
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Bobbo VCD, Jara CP, Mendes NF, Morari J, Velloso LA, Araújo EP. Interleukin-6 Expression by Hypothalamic Microglia in Multiple Inflammatory Contexts: A Systematic Review. BIOMED RESEARCH INTERNATIONAL 2019; 2019:1365210. [PMID: 31534953 PMCID: PMC6724433 DOI: 10.1155/2019/1365210] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Accepted: 07/25/2019] [Indexed: 12/14/2022]
Abstract
Interleukin-6 (IL-6) is a unique cytokine that can play both pro- and anti-inflammatory roles depending on the anatomical site and conditions under which it has been induced. Specific neurons of the hypothalamus provide important signals to control food intake and energy expenditure. In individuals with obesity, a microglia-dependent inflammatory response damages the neural circuits responsible for maintaining whole-body energy homeostasis, resulting in a positive energy balance. However, little is known about the role of IL-6 in the regulation of hypothalamic microglia. In this systematic review, we asked what types of conditions and stimuli could modulate microglial IL-6 expression in murine model. We searched the PubMed and Web of Science databases and analyzed 13 articles that evaluated diverse contexts and study models focused on IL-6 expression and microglia activation, including the effects of stress, hypoxia, infection, neonatal overfeeding and nicotine exposure, lipopolysaccharide stimulus, hormones, exercise protocols, and aging. The results presented in this review emphasized the role of "injury-like" stimuli, under which IL-6 acts as a proinflammatory cytokine, concomitant with marked microglial activation, which drive hypothalamic neuroinflammation. Emerging evidence indicates an important correlation of basal IL-6 levels and microglial function with the maintenance of hypothalamic homeostasis. Advances in our understanding of these different contexts will lead to the development of more specific pharmacological approaches for the management of acute and chronic conditions, like obesity and metabolic diseases, without disturbing the homeostatic functions of IL-6 and microglia in the hypothalamus.
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Affiliation(s)
- Vanessa C. D. Bobbo
- Faculty of Nursing, University of Campinas, SP 13083-887, Brazil
- Laboratory of Cell Signaling, Obesity and Comorbidities Research Center, University of Campinas, SP 13083-864, Brazil
| | - Carlos P. Jara
- Faculty of Nursing, University of Campinas, SP 13083-887, Brazil
- Laboratory of Cell Signaling, Obesity and Comorbidities Research Center, University of Campinas, SP 13083-864, Brazil
| | - Natália F. Mendes
- Faculty of Nursing, University of Campinas, SP 13083-887, Brazil
- Laboratory of Cell Signaling, Obesity and Comorbidities Research Center, University of Campinas, SP 13083-864, Brazil
| | - Joseane Morari
- Laboratory of Cell Signaling, Obesity and Comorbidities Research Center, University of Campinas, SP 13083-864, Brazil
| | - Lício A. Velloso
- Laboratory of Cell Signaling, Obesity and Comorbidities Research Center, University of Campinas, SP 13083-864, Brazil
| | - Eliana P. Araújo
- Faculty of Nursing, University of Campinas, SP 13083-887, Brazil
- Laboratory of Cell Signaling, Obesity and Comorbidities Research Center, University of Campinas, SP 13083-864, Brazil
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Barros W, David M, Souza A, Silva M, Matos R. Can the effects of environmental enrichment modulate BDNF expression in hippocampal plasticity? A systematic review of animal studies. Synapse 2019; 73:e22103. [PMID: 31056812 DOI: 10.1002/syn.22103] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 04/28/2019] [Accepted: 04/29/2019] [Indexed: 12/11/2022]
Abstract
BACKGROUND AND AIM Environmental enrichment (EE) can be related to changes in the expression of brain-derived neurotrophic factor (BDNF) in the hippocampus of adult rodents. Exposure to EE may also induce neurogenesis in the dentate gyrus (DG). The aim of this systematic review was to analyze the current literature on the correlation between neurogenesis and BDNF expression in the hippocampal DG region resulting from exposure to EE, which is associated with changes in memory, in rodents. METHODS Bibliographic searches of the Medline/PubMed and ScienceDirect databases were carried out, and 334 studies were found. A predefined protocol was used and registered on PROSPERO, and 32 studies were included for qualitative synthesis. The PRISMA was used to report this systematic review. RESULTS Most of the included studies showed that there is little evidence in the literature demonstrating that memory changes resulting from EE are dependent on BDNF expression and that there is an induction of neurogenesis in the hippocampal DG. However, the observed increase in molecular expression levels and cell proliferation is dependent on the age, the timing and duration of exposure to EE. Regarding the methodological quality of the studies, the majority presented a risk of bias due to the high variability in the age of the animals. CONCLUSION There are few studies in the literature that correlate the molecular and cellular mechanisms involved in neurogenesis in the hippocampal DG with BDNF expression in this region in rodents exposed to EE; however, there are other factors that can modulate this neurogenesis.
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Affiliation(s)
- Waleska Barros
- Programa de Pós-Graduação em Neuropsiquiatria e Ciências do Comportamento, Universidade Federal de Pernambuco (UFPE), Recife, Brazil.,CITENC (Centro integrado de tecnologia em neurociência), Centro Integrado de Tecnologia e Pesquisa (CINTEP) - Centro Universitário Osman Lins (FACOL), Vitória de Santo Antão, Brazil
| | - Mirian David
- Programa de Pós-Graduação em Neuropsiquiatria e Ciências do Comportamento, Universidade Federal de Pernambuco (UFPE), Recife, Brazil
| | - Ana Souza
- Fisioterapia, Centro Universitário Osman Lins (FACOL), Vitória de Santo Antão, Brazil
| | - Mariluce Silva
- Fisioterapia, Centro Universitário Osman Lins (FACOL), Vitória de Santo Antão, Brazil
| | - Rhowena Matos
- Programa de Pós-Graduação em Neuropsiquiatria e Ciências do Comportamento, Universidade Federal de Pernambuco (UFPE), Recife, Brazil.,Núcleo de Educação Física e Ciências do Esporte, Universidade Federal de Pernambuco Centro Acadêmico de Vitória (CAV), Vitória de Santo Antão, Brazil
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