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Anwar MM, Pérez-Martínez L, Pedraza-Alva G. Exploring the Significance of Microglial Phenotypes and Morphological Diversity in Neuroinflammation and Neurodegenerative Diseases: From Mechanisms to Potential Therapeutic Targets. Immunol Invest 2024:1-56. [PMID: 38836373 DOI: 10.1080/08820139.2024.2358446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2024]
Abstract
Studying various microglial phenotypes and their functions in neurodegenerative diseases is crucial due to the intricate nature of their phenomics and their vital immunological role. Microglia undergo substantial phenomic changes, encompassing morphological, transcriptional, and functional aspects, resulting in distinct cell types with diverse structures, functions, properties, and implications. The traditional classification of microglia as ramified, M1 (proinflammatory), or M2 (anti-inflammatory) phenotypes is overly simplistic, failing to capture the wide range of recently identified microglial phenotypes in various brain regions affected by neurodegenerative diseases. Altered and activated microglial phenotypes deviating from the typical ramified structure are significant features of many neurodegenerative conditions. Understanding the precise role of each microglial phenotype is intricate and sometimes contradictory. This review specifically focuses on elucidating recent modifications in microglial phenotypes within neurodegenerative diseases. Recognizing the heterogeneity of microglial phenotypes in diseased states can unveil novel therapeutic strategies for targeting microglia in neurodegenerative diseases. Moreover, the exploration of the use of healthy isolated microglia to mitigate disease progression has provided an innovative perspective. In conclusion, this review discusses the dynamic landscape of mysterious microglial phenotypes, emphasizing the need for a nuanced understanding to pave the way for innovative therapeutic strategies for neurodegenerative diseases.
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Affiliation(s)
- Mai M Anwar
- Department of Biochemistry, National Organization for Drug Control and Research (NODCAR)/Egyptian Drug Authority (EDA), Cairo, Egypt
| | - Leonor Pérez-Martínez
- Neuroimmunobiology Laboratory, Department of Molecular Medicine and Bioprocesses, Institute of Biotechnology, National Autonomous University of Mexico, Cuernavaca, Morelos, Mexico
| | - Gustavo Pedraza-Alva
- Neuroimmunobiology Laboratory, Department of Molecular Medicine and Bioprocesses, Institute of Biotechnology, National Autonomous University of Mexico, Cuernavaca, Morelos, Mexico
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2
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Field SE, Curle AJ, Barker RA. Inflammation and Huntington's disease - a neglected therapeutic target? Expert Opin Investig Drugs 2024; 33:451-467. [PMID: 38758356 DOI: 10.1080/13543784.2024.2348738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Accepted: 04/24/2024] [Indexed: 05/18/2024]
Abstract
INTRODUCTION Huntington's Disease (HD) is a genetic neurodegenerative disease for which there is currently no disease-modifying treatment. One of several underlying mechanisms proposed to be involved in HD pathogenesis is inflammation; there is now accumulating evidence that the immune system may play an integral role in disease pathology and progression. As such, modulation of the immune system could be a potential therapeutic target for HD. AREAS COVERED To date, the number of trials targeting immune aspects of HD has been limited. However, targeting it, may have great advantages over other therapeutic areas, given that many drugs already exist that have actions in this system coupled to the fact that inflammation can be measured both peripherally and, to some extent, centrally using CSF and PET imaging. In this review, we look at evidence that the immune system and the newly emerging area of the microbiome are altered in HD patients, and then present and discuss clinical trials that have targeted different parts of the immune system. EXPERT OPINION We then conclude by discussing how this field might develop going forward, focusing on the role of imaging and other biomarkers to monitor central immune activation and response to novel treatments in HD.
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Affiliation(s)
- Sophie E Field
- Department of Clinical Neurosciences, John van Geest Centre for Brain Repair, and MRC-WT Cambridge Stem Cell Institute, University of Cambridge, Cambridge, UK
| | - Annabel J Curle
- Department of Clinical Neurosciences, John van Geest Centre for Brain Repair, and MRC-WT Cambridge Stem Cell Institute, University of Cambridge, Cambridge, UK
| | - Roger A Barker
- Department of Clinical Neurosciences, John van Geest Centre for Brain Repair, and MRC-WT Cambridge Stem Cell Institute, University of Cambridge, Cambridge, UK
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Strohm AO, Johnston C, Hernady E, Marples B, O'Banion MK, Majewska AK. Cranial irradiation disrupts homeostatic microglial dynamic behavior. J Neuroinflammation 2024; 21:82. [PMID: 38570852 PMCID: PMC10993621 DOI: 10.1186/s12974-024-03073-z] [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: 12/18/2023] [Accepted: 03/22/2024] [Indexed: 04/05/2024] Open
Abstract
Cranial irradiation causes cognitive deficits that are in part mediated by microglia, the resident immune cells of the brain. Microglia are highly reactive, exhibiting changes in shape and morphology depending on the function they are performing. Additionally, microglia processes make dynamic, physical contacts with different components of their environment to monitor the functional state of the brain and promote plasticity. Though evidence suggests radiation perturbs homeostatic microglia functions, it is unknown how cranial irradiation impacts the dynamic behavior of microglia over time. Here, we paired in vivo two-photon microscopy with a transgenic mouse model that labels cortical microglia to follow these cells and determine how they change over time in cranial irradiated mice and their control littermates. We show that a single dose of 10 Gy cranial irradiation disrupts homeostatic cortical microglia dynamics during a 1-month time course. We found a lasting loss of microglial cells following cranial irradiation, coupled with a modest dysregulation of microglial soma displacement at earlier timepoints. The homogeneous distribution of microglia was maintained, suggesting microglia rearrange themselves to account for cell loss and maintain territorial organization following cranial irradiation. Furthermore, we found cranial irradiation reduced microglia coverage of the parenchyma and their surveillance capacity, without overtly changing morphology. Our results demonstrate that a single dose of radiation can induce changes in microglial behavior and function that could influence neurological health. These results set the foundation for future work examining how cranial irradiation impacts complex cellular dynamics in the brain which could contribute to the manifestation of cognitive deficits.
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Affiliation(s)
- Alexandra O Strohm
- Department of Environmental Medicine, University of Rochester Medical Center, Rochester, NY, 14642, USA
| | - Carl Johnston
- Department of Pediatrics, University of Rochester Medical Center, Rochester, NY, 14642, USA
| | - Eric Hernady
- Department of Radiation Oncology, University of Rochester Medical Center, Rochester, NY, 14642, USA
| | - Brian Marples
- Department of Radiation Oncology, University of Rochester Medical Center, Rochester, NY, 14642, USA
| | - M Kerry O'Banion
- Department of Neuroscience, University of Rochester Medical Center, Rochester, NY, 14642, USA
- Del Monte Institute for Neuroscience, University of Rochester Medical Center, Rochester, NY, 14642, USA
| | - Ania K Majewska
- Department of Neuroscience, University of Rochester Medical Center, Rochester, NY, 14642, USA.
- Del Monte Institute for Neuroscience, University of Rochester Medical Center, Rochester, NY, 14642, USA.
- Center for Visual Science, University of Rochester Medical Center, Rochester, NY, 14642, USA.
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Creus-Muncunill J, Haure-Mirande JV, Mattei D, Bons J, Ramirez AV, Hamilton BW, Corwin C, Chowdhury S, Schilling B, Ellerby LM, Ehrlich ME. TYROBP/DAP12 knockout in Huntington's disease Q175 mice cell-autonomously decreases microglial expression of disease-associated genes and non-cell-autonomously mitigates astrogliosis and motor deterioration. J Neuroinflammation 2024; 21:66. [PMID: 38459557 PMCID: PMC10924371 DOI: 10.1186/s12974-024-03052-4] [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: 10/15/2023] [Accepted: 02/19/2024] [Indexed: 03/10/2024] Open
Abstract
INTRODUCTION Huntington's disease (HD) is a fatal neurodegenerative disorder caused by an expansion of the CAG trinucleotide repeat in the Huntingtin gene (HTT). Immune activation is abundant in the striatum of HD patients. Detection of active microglia at presymptomatic stages suggests that microgliosis is a key early driver of neuronal dysfunction and degeneration. Recent studies showed that deletion of Tyrobp, a microglial protein, ameliorates neuronal dysfunction in Alzheimer's disease amyloidopathy and tauopathy mouse models while decreasing components of the complement subnetwork. OBJECTIVE While TYROBP/DAP12-mediated microglial activation is detrimental for some diseases such as peripheral nerve injury, it is beneficial for other diseases. We sought to determine whether the TYROBP network is implicated in HD and whether Tyrobp deletion impacts HD striatal function and transcriptomics. METHODS To test the hypothesis that Tyrobp deficiency would be beneficial in an HD model, we placed the Q175 HD mouse model on a Tyrobp-null background. We characterized these mice with a combination of behavioral testing, immunohistochemistry, transcriptomic and proteomic profiling. Further, we evaluated the gene signature in isolated Q175 striatal microglia, with and without Tyrobp. RESULTS Comprehensive analysis of publicly available human HD transcriptomic data revealed that the TYROBP network is overactivated in the HD putamen. The Q175 mice showed morphologic microglial activation, reduced levels of post-synaptic density-95 protein and motor deficits at 6 and 9 months of age, all of which were ameliorated on the Tyrobp-null background. Gene expression analysis revealed that lack of Tyrobp in the Q175 model does not prevent the decrease in the expression of striatal neuronal genes but reduces pro-inflammatory pathways that are specifically active in HD human brain, including genes identified as detrimental in neurodegenerative diseases, e.g. C1q and members of the Ccr5 signaling pathway. Integration of transcriptomic and proteomic data revealed that astrogliosis and complement system pathway were reduced after Tyrobp deletion, which was further validated by immunofluorescence analysis. CONCLUSIONS Our data provide molecular and functional support demonstrating that Tyrobp deletion prevents many of the abnormalities in the HD Q175 mouse model, suggesting that the Tyrobp pathway is a potential therapeutic candidate for Huntington's disease.
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Affiliation(s)
| | | | - Daniele Mattei
- Nash Family Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, USA
| | - Joanna Bons
- Buck Institute for Research on Aging, Novato, CA, USA
| | - Angie V Ramirez
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, USA
| | - B Wade Hamilton
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, USA
| | - Chuhyon Corwin
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, USA
| | - Sarah Chowdhury
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, USA
| | | | | | - Michelle E Ehrlich
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, USA.
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Fan H, Zhang M, Wen J, Wang S, Yuan M, Sun H, Shu L, Yang X, Pu Y, Cai Z. Microglia in brain aging: An overview of recent basic science and clinical research developments. J Biomed Res 2024; 38:122-136. [PMID: 38403286 PMCID: PMC11001587 DOI: 10.7555/jbr.37.20220220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 12/25/2022] [Accepted: 01/12/2023] [Indexed: 02/27/2024] Open
Abstract
Aging is characterized by progressive degeneration of tissues and organs, and it is positively associated with an increased mortality rate. The brain, as one of the most significantly affected organs, experiences age-related changes, including abnormal neuronal activity, dysfunctional calcium homeostasis, dysregulated mitochondrial function, and increased levels of reactive oxygen species. These changes collectively contribute to cognitive deterioration. Aging is also a key risk factor for neurodegenerative diseases, such as Alzheimer's disease and Parkinson's disease. For many years, neurodegenerative disease investigations have primarily focused on neurons, with less attention given to microglial cells. However, recently, microglial homeostasis has emerged as an important mediator in neurological disease pathogenesis. Here, we provide an overview of brain aging from the perspective of the microglia. In doing so, we present the current knowledge on the correlation between brain aging and the microglia, summarize recent progress of investigations about the microglia in normal aging, Alzheimer's disease, Parkinson's disease, Huntington's disease, and amyotrophic lateral sclerosis, and then discuss the correlation between the senescent microglia and the brain, which will culminate with a presentation of the molecular complexity involved in the microglia in brain aging with suggestions for healthy aging.
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Affiliation(s)
- Haixia Fan
- Chongqing Medical University, Chongqing 400042, China
- Department of Neurology, Chongqing General Hospital, Chongqing 400013, China
- Chongqing Key Laboratory of Neurodegenerative Diseases, Chongqing 400013, China
- Department of Neurology, the First Hospital of Shanxi Medical University, Taiyuan, Shanxi 030001, China
| | - Minheng Zhang
- Department of Gerontology, the First People's Hospital of Jinzhong, Jinzhong, Shanxi 030009, China
| | - Jie Wen
- Chongqing Medical University, Chongqing 400042, China
- Department of Neurology, Chongqing General Hospital, Chongqing 400013, China
- Chongqing Key Laboratory of Neurodegenerative Diseases, Chongqing 400013, China
| | - Shengyuan Wang
- Chongqing Medical University, Chongqing 400042, China
- Department of Neurology, Chongqing General Hospital, Chongqing 400013, China
- Chongqing Key Laboratory of Neurodegenerative Diseases, Chongqing 400013, China
| | - Minghao Yuan
- Chongqing Medical University, Chongqing 400042, China
- Department of Neurology, Chongqing General Hospital, Chongqing 400013, China
- Chongqing Key Laboratory of Neurodegenerative Diseases, Chongqing 400013, China
| | - Houchao Sun
- Department of Neurology, Chongqing General Hospital, Chongqing 400013, China
- Chongqing Key Laboratory of Neurodegenerative Diseases, Chongqing 400013, China
| | - Liu Shu
- Chongqing Medical University, Chongqing 400042, China
- Department of Neurology, Chongqing General Hospital, Chongqing 400013, China
- Chongqing Key Laboratory of Neurodegenerative Diseases, Chongqing 400013, China
| | - Xu Yang
- Chongqing Medical University, Chongqing 400042, China
- Department of Neurology, Chongqing General Hospital, Chongqing 400013, China
- Chongqing Key Laboratory of Neurodegenerative Diseases, Chongqing 400013, China
| | - Yinshuang Pu
- Department of Neurology, Chongqing General Hospital, Chongqing 400013, China
- Chongqing Key Laboratory of Neurodegenerative Diseases, Chongqing 400013, China
| | - Zhiyou Cai
- Chongqing Medical University, Chongqing 400042, China
- Department of Neurology, Chongqing General Hospital, Chongqing 400013, China
- Chongqing Key Laboratory of Neurodegenerative Diseases, Chongqing 400013, China
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Bobotis BC, Halvorson T, Carrier M, Tremblay MÈ. Established and emerging techniques for the study of microglia: visualization, depletion, and fate mapping. Front Cell Neurosci 2024; 18:1317125. [PMID: 38425429 PMCID: PMC10902073 DOI: 10.3389/fncel.2024.1317125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Accepted: 01/15/2024] [Indexed: 03/02/2024] Open
Abstract
The central nervous system (CNS) is an essential hub for neuronal communication. As a major component of the CNS, glial cells are vital in the maintenance and regulation of neuronal network dynamics. Research on microglia, the resident innate immune cells of the CNS, has advanced considerably in recent years, and our understanding of their diverse functions continues to grow. Microglia play critical roles in the formation and regulation of neuronal synapses, myelination, responses to injury, neurogenesis, inflammation, and many other physiological processes. In parallel with advances in microglial biology, cutting-edge techniques for the characterization of microglial properties have emerged with increasing depth and precision. Labeling tools and reporter models are important for the study of microglial morphology, ultrastructure, and dynamics, but also for microglial isolation, which is required to glean key phenotypic information through single-cell transcriptomics and other emerging approaches. Strategies for selective microglial depletion and modulation can provide novel insights into microglia-targeted treatment strategies in models of neuropsychiatric and neurodegenerative conditions, cancer, and autoimmunity. Finally, fate mapping has emerged as an important tool to answer fundamental questions about microglial biology, including their origin, migration, and proliferation throughout the lifetime of an organism. This review aims to provide a comprehensive discussion of these established and emerging techniques, with applications to the study of microglia in development, homeostasis, and CNS pathologies.
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Affiliation(s)
- Bianca Caroline Bobotis
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
- Centre for Advanced Materials and Related Technology, Victoria, BC, Canada
| | - Torin Halvorson
- Department of Medicine, University of British Columbia, Vancouver, BC, Canada
- Department of Surgery, University of British Columbia, Vancouver, BC, Canada
- British Columbia Children’s Hospital Research Institute, Vancouver, BC, Canada
| | - Micaël Carrier
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
- Département de Psychiatrie et de Neurosciences, Faculté de Médecine, Université Laval, Québec City, QC, Canada
- Axe neurosciences, Centre de Recherche du CHU de Québec, Université Laval, Québec City, QC, Canada
| | - Marie-Ève Tremblay
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
- Centre for Advanced Materials and Related Technology, Victoria, BC, Canada
- Axe neurosciences, Centre de Recherche du CHU de Québec, Université Laval, Québec City, QC, Canada
- Department of Molecular Medicine, Université Laval, Québec City, QC, Canada
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7
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Carrier M, Hui CW, Watters V, Šimončičová E, Picard K, González Ibáñez F, Vernoux N, Droit A, Desjardins M, Tremblay MÈ. Behavioral as well as hippocampal transcriptomic and microglial responses differ across sexes in adult mouse offspring exposed to a dual genetic and environmental challenge. Brain Behav Immun 2024; 116:126-139. [PMID: 38016491 DOI: 10.1016/j.bbi.2023.11.025] [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: 02/27/2023] [Revised: 10/15/2023] [Accepted: 11/23/2023] [Indexed: 11/30/2023] Open
Abstract
INTRODUCTION A wide range of positive, negative, and cognitive symptoms compose the clinical presentation of schizophrenia. Schizophrenia is a multifactorial disorder in which genetic and environmental risk factors interact for a full emergence of the disorder. Infectious challenges during pregnancy are a well-known environmental risk factor for schizophrenia. Also, genetic variants affecting the function of fractalkine signaling between neurons and microglia were linked to schizophrenia. Translational animal models recapitulating these complex gene-environment associations have a great potential to untangle schizophrenia neurobiology and propose new therapeutic strategies. METHODS Given that genetic variants affecting the function of fractalkine signaling between neurons and microglia were linked to schizophrenia, we compared the outcomes of a well-characterized model of maternal immune activation induced using the viral mimetic polyinosinic:polycytidylic acid (Poly I:C) in wild-type versus fractalkine receptor knockout mice. Possible behavioral and immune alterations were assessed in male and female offspring during adulthood. Considering the role of the hippocampus in schizophrenia, microglial analyses and bulk RNA sequencing were performed within this region to assess the neuroimmune dynamics at play. Males and females were examined separately. RESULTS Offspring exposed to the dual challenge paradigm exhibited symptoms relevant to schizophrenia and unpredictably to mood disorders. Males displayed social and cognitive deficits related to schizophrenia, while females mainly presented anxiety-like behaviors related to mood disorders. Hippocampal microglia in females exposed to the dual challenge were hypertrophic, indicative of an increased surveillance, whereas those in males showed on the other end of the spectrum blunted morphologies with a reduced phagocytosis. Hippocampal bulk-RNA sequencing further revealed a downregulation in females of genes related to GABAergic transmission, which represents one of the main proposed causes of mood disorders. CONCLUSIONS Building on previous results, we identified in the current study distinctive behavioral phenotypes in female mice exposed to a dual genetic and environmental challenge, thus proposing a new model of neurodevelopmentally-associated mood and affective symptoms. This paves the way to future sex-specific investigations into the susceptibility to developmental challenges using animal models based on genetic and immune vulnerability as presented here.
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Affiliation(s)
- Micaël Carrier
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada; Department of Psychiatry and Neuroscience, Faculty of Medicine, Université Laval, Québec City, QC, Canada; Centre de recherche du CHU de Québec-Université Laval, Québec City, QC, Canada
| | - Chin W Hui
- Centre de recherche du CHU de Québec-Université Laval, Québec City, QC, Canada
| | - Valérie Watters
- Centre de recherche du CHU de Québec-Université Laval, Québec City, QC, Canada
| | - Eva Šimončičová
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
| | - Katherine Picard
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada; Centre de recherche du CHU de Québec-Université Laval, Québec City, QC, Canada; Département de médecine moléculaire, Faculté de médecine, Université Laval, Québec City, QC, Canada
| | - Fernando González Ibáñez
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada; Centre de recherche du CHU de Québec-Université Laval, Québec City, QC, Canada; Département de médecine moléculaire, Faculté de médecine, Université Laval, Québec City, QC, Canada
| | - Nathalie Vernoux
- Centre de recherche du CHU de Québec-Université Laval, Québec City, QC, Canada
| | - Arnaud Droit
- Centre de recherche du CHU de Québec-Université Laval, Québec City, QC, Canada; Département de médecine moléculaire, Faculté de médecine, Université Laval, Québec City, QC, Canada
| | - Michèle Desjardins
- Department of Physics, Physical Engineering and Optics, Université Laval, Québec City, QC, Canada; Oncology Axis, Centre de Recherche du CHU de Québec, Université Laval, Québec City, QC, Canada
| | - Marie-Ève Tremblay
- Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, BC, Canada; Department of Neurology and Neurosurgery, McGill University, Montréal, QC, Canada; Centre for Advanced Materials and Related Technology (CAMTEC), University of Victoria, Victoria, BC, Canada.
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Steinberg N, Galleguillos D, Zaidi A, Horkey M, Sipione S. Naïve Huntington's disease microglia mount a normal response to inflammatory stimuli but display a partially impaired development of innate immune tolerance that can be counteracted by ganglioside GM1. J Neuroinflammation 2023; 20:276. [PMID: 37996924 PMCID: PMC10668379 DOI: 10.1186/s12974-023-02963-y] [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: 03/07/2023] [Accepted: 11/18/2023] [Indexed: 11/25/2023] Open
Abstract
Chronic activation and dysfunction of microglia have been implicated in the pathogenesis and progression of many neurodegenerative disorders, including Huntington's disease (HD). HD is a genetic condition caused by a mutation that affects the folding and function of huntingtin (HTT). Signs of microglia activation have been observed in HD patients even before the onset of symptoms. It is unclear, however, whether pro-inflammatory microglia activation in HD results from cell-autonomous expression of mutant HTT, is the response of microglia to a diseased brain environment, or both. In this study, we used primary microglia isolated from HD knock-in (Q140) and wild-type (Q7) mice to investigate their response to inflammatory conditions in vitro in the absence of confounding effects arising from brain pathology. We show that naïve Q140 microglia do not undergo spontaneous pro-inflammatory activation and respond to inflammatory triggers, including stimulation of TLR4 and TLR2 and exposure to necrotic cells, with similar kinetics of pro-inflammatory gene expression as wild-type microglia. Upon termination of the inflammatory insult, the transcription of pro-inflammatory cytokines is tapered off in Q140 and wild-type microglia with similar kinetics. However, the ability of Q140 microglia to develop tolerance in response to repeated inflammatory stimulations is partially impaired in vitro and in vivo, potentially contributing to the establishment of chronic neuroinflammation in HD. We further show that ganglioside GM1, a glycosphingolipid with anti-inflammatory effects on wild-type microglia, not only decreases the production of pro-inflammatory cytokines and nitric oxide in activated Q140 microglia, but also dramatically dampen microglia response to re-stimulation with LPS in an experimental model of tolerance. These effects are independent from the expression of interleukin 1 receptor associated kinase 3 (Irak-3), a strong modulator of LPS signaling involved in the development of innate immune tolerance and previously shown to be upregulated by immune cell treatment with gangliosides. Altogether, our data suggest that external triggers are required for HD microglia activation, but a cell-autonomous dysfunction that affects the ability of HD microglia to acquire tolerance might contribute to the establishment of neuroinflammation in HD. Administration of GM1 might be beneficial to attenuate chronic microglia activation and neuroinflammation.
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Affiliation(s)
- Noam Steinberg
- Department of Pharmacology, Neuroscience and Mental Health Institute and Glycomics Institute of Alberta, University of Alberta, Edmonton, AB, Canada
| | - Danny Galleguillos
- Department of Pharmacology, Neuroscience and Mental Health Institute and Glycomics Institute of Alberta, University of Alberta, Edmonton, AB, Canada
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Asifa Zaidi
- Department of Pharmacology, Neuroscience and Mental Health Institute and Glycomics Institute of Alberta, University of Alberta, Edmonton, AB, Canada
| | | | - Simonetta Sipione
- Department of Pharmacology, Neuroscience and Mental Health Institute and Glycomics Institute of Alberta, University of Alberta, Edmonton, AB, Canada.
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Wilton DK, Mastro K, Heller MD, Gergits FW, Willing CR, Fahey JB, Frouin A, Daggett A, Gu X, Kim YA, Faull RLM, Jayadev S, Yednock T, Yang XW, Stevens B. Microglia and complement mediate early corticostriatal synapse loss and cognitive dysfunction in Huntington's disease. Nat Med 2023; 29:2866-2884. [PMID: 37814059 PMCID: PMC10667107 DOI: 10.1038/s41591-023-02566-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Accepted: 08/24/2023] [Indexed: 10/11/2023]
Abstract
Huntington's disease (HD) is a devastating monogenic neurodegenerative disease characterized by early, selective pathology in the basal ganglia despite the ubiquitous expression of mutant huntingtin. The molecular mechanisms underlying this region-specific neuronal degeneration and how these relate to the development of early cognitive phenotypes are poorly understood. Here we show that there is selective loss of synaptic connections between the cortex and striatum in postmortem tissue from patients with HD that is associated with the increased activation and localization of complement proteins, innate immune molecules, to these synaptic elements. We also found that levels of these secreted innate immune molecules are elevated in the cerebrospinal fluid of premanifest HD patients and correlate with established measures of disease burden.In preclinical genetic models of HD, we show that complement proteins mediate the selective elimination of corticostriatal synapses at an early stage in disease pathogenesis, marking them for removal by microglia, the brain's resident macrophage population. This process requires mutant huntingtin to be expressed in both cortical and striatal neurons. Inhibition of this complement-dependent elimination mechanism through administration of a therapeutically relevant C1q function-blocking antibody or genetic ablation of a complement receptor on microglia prevented synapse loss, increased excitatory input to the striatum and rescued the early development of visual discrimination learning and cognitive flexibility deficits in these models. Together, our findings implicate microglia and the complement cascade in the selective, early degeneration of corticostriatal synapses and the development of cognitive deficits in presymptomatic HD; they also provide new preclinical data to support complement as a therapeutic target for early intervention.
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Affiliation(s)
- Daniel K Wilton
- F. M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, US.
| | - Kevin Mastro
- F. M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, US
| | - Molly D Heller
- F. M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, US
| | - Frederick W Gergits
- F. M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, US
| | - Carly Rose Willing
- F. M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, US
| | - Jaclyn B Fahey
- F. M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, US
| | - Arnaud Frouin
- F. M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, US
| | - Anthony Daggett
- Center for Neurobehavioral Genetics, Jane and Terry Semel Institute for Neuroscience and Human Behavior, Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine at University of California, Los Angeles, CA, USA
| | - Xiaofeng Gu
- Center for Neurobehavioral Genetics, Jane and Terry Semel Institute for Neuroscience and Human Behavior, Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine at University of California, Los Angeles, CA, USA
| | - Yejin A Kim
- F. M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, US
| | - Richard L M Faull
- Department of Anatomy with Radiology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Suman Jayadev
- Department of Neurology, University of Washington, Seattle, WA, USA
- Division of Medical Genetics, Department of Medicine, University of Washington, Seattle, WA, USA
| | - Ted Yednock
- Annexon Biosciences, South San Francisco, CA, USA
| | - X William Yang
- Center for Neurobehavioral Genetics, Jane and Terry Semel Institute for Neuroscience and Human Behavior, Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine at University of California, Los Angeles, CA, USA
| | - Beth Stevens
- F. M. Kirby Neurobiology Center, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, US.
- Stanley Center, Broad Institute, Cambridge, MA, USA.
- Howard Hughes Medical Institute, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA.
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10
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González Ibáñez F, Halvorson T, Sharma K, McKee CG, Carrier M, Picard K, Vernoux N, Bisht K, Deslauriers J, Lalowski M, Tremblay MÈ. Ketogenic diet changes microglial morphology and the hippocampal lipidomic profile differently in stress susceptible versus resistant male mice upon repeated social defeat. Brain Behav Immun 2023; 114:383-406. [PMID: 37689276 DOI: 10.1016/j.bbi.2023.09.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 08/30/2023] [Accepted: 09/06/2023] [Indexed: 09/11/2023] Open
Abstract
Psychological stress confers an increased risk for several diseases including psychiatric conditions. The susceptibility to psychological stress is modulated by various factors, many of them being modifiable lifestyle choices. The ketogenic diet (KD) has emerged as a dietary regime that offers positive outcomes on mood and health status. Psychological stress and elevated inflammation are common features of neuropsychiatric disorders such as certain types of major depressive disorder. KD has been attributed anti-inflammatory properties that could underlie its beneficial consequences on the brain and behavior. Microglia are the main drivers of inflammation in the central nervous system. They are known to respond to both dietary changes and psychological stress, notably by modifying their production of cytokines and relationships among the brain parenchyma. To assess the interactions between KD and the stress response, including effects on microglia, we examined adult male mice on control diet (CD) versus KD that underwent 10 days of repeated social defeat (RSD) or remained non-stressed (controls; CTRLs). Through a social interaction test, stressed mice were classified as susceptible (SUS) or resistant (RES) to RSD. The mouse population fed a KD tended to have a higher proportion of individuals classified as RES following RSD. Microglial morphology and ultrastructure were then analyzed in the ventral hippocampus CA1, a brain region known to present structural alterations as a response to psychological stress. Distinct changes in microglial soma and arborization linked to the KD, SUS and RES phenotypes were revealed. Ultrastructural analysis by electron microscopy showed a clear reduction of cellular stress markers in microglia from KD fed animals. Furthermore, ultrastructural analysis showed that microglial contacts with synaptic elements were reduced in the SUS compared to the RES and CTRL groups. Hippocampal lipidomic analyses lastly identified a distinct lipid profile in SUS animals compared to CTRLs. These key differences, combined with the distinct microglial responses to diet and stress, indicate that unique metabolic changes may underlie the stress susceptibility phenotypes. Altogether, our results reveal novel mechanisms by which a KD might improve the resistance to psychological stress.
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Affiliation(s)
- Fernando González Ibáñez
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, Quebec, Canada; Département de Médecine Moléculaire, Université Laval, Québec, Quebec, Canada; Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada
| | - Torin Halvorson
- Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada; Department of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Kaushik Sharma
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, Quebec, Canada; Département de Médecine Moléculaire, Université Laval, Québec, Quebec, Canada; Department of Chemistry, Purdue University, West Lafayette, Indiana, United States
| | - Chloe Grace McKee
- Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada
| | - Micaël Carrier
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, Quebec, Canada; Département de Médecine Moléculaire, Université Laval, Québec, Quebec, Canada; Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada
| | - Katherine Picard
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, Quebec, Canada; Département de Médecine Moléculaire, Université Laval, Québec, Quebec, Canada; Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada
| | - Nathalie Vernoux
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, Quebec, Canada
| | - Kanchan Bisht
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, Quebec, Canada; Département de Médecine Moléculaire, Université Laval, Québec, Quebec, Canada; Department of Chemistry, Purdue University, West Lafayette, Indiana, United States
| | | | - Maciej Lalowski
- Department of Gene Expression, Institute of Molecular Biology and Biotechnology, Faculty of Biology, Adam Mickiewicz University, Poznań, Poland; Biochemistry/Developmental Biology and HiLIFE, Meilahti Clinical Proteomics Core Facility, University of Helsinki, Finland
| | - Marie-Ève Tremblay
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, Quebec, Canada; Département de Médecine Moléculaire, Université Laval, Québec, Quebec, Canada; Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada; Neurology and Neurosurgery Department, McGill University, Montréal, Quebec, Canada; Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, British Columbia, Canada; Centre for Advanced Materials and Related Technology (CAMTEC), University of Victoria, British Columbia, Canada.
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11
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Zhuang H, Li Q, Sun C, Xu D, Gan G, Zhang C, Chen C, Yuan Y, Liu L, Xiao Y, Yao X, Wang C, Kang X, Yang C, Zhao J, Chen W, Wang J, Li J, Luo C, Wang J, Jia X, Yu Z, Liu L. Voluntary wheel exercise ameliorates cognitive impairment, hippocampal neurodegeneration and microglial abnormalities preceded by demyelination in a male mouse model of noise-induced hearing loss. Brain Behav Immun 2023; 114:325-348. [PMID: 37683962 DOI: 10.1016/j.bbi.2023.09.002] [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: 05/26/2023] [Revised: 08/23/2023] [Accepted: 09/05/2023] [Indexed: 09/10/2023] Open
Abstract
Acquired peripheral hearing loss (APHL) in midlife has been identified as the greatest modifiable risk factor for dementia; however, the pathophysiological neural mechanisms linking APHL with an increased risk of dementia remain to be elucidated. Here, in an adult male mouse model of noise-induced hearing loss (NIHL), one of the most common forms of APHL, we demonstrated accelerated age-related cognitive decline and hippocampal neurodegeneration during a 6-month follow-up period, accompanied by progressive hippocampal microglial aberrations preceded by immediate-onset transient elevation in serum glucocorticoids and delayed-onset sustained myelin disruption in the hippocampus. Pretreatment with the glucocorticoid receptor antagonist RU486 before stressful noise exposure partially mitigated the early activation of hippocampal microglia, which were present at 7 days post noise exposure (7DPN), but had no impact on later microglial aberrations, hippocampal neurodegeneration, or cognitive decline exhibited at 1 month post noise exposure (1MPN). One month of voluntary wheel exercise following noise exposure barely affected either the hearing threshold shift or hippocampal myelin changes but effectively countered cognitive impairment and the decline in hippocampal neurogenesis in NIHL mice at 1MPN, paralleled by the normalization of microglial morphology, which coincided with a reduction in microglial myelin inclusions and a restoration of microglial hypoxia-inducible factor-1α (HIF1α) expression. Our results indicated that accelerated cognitive deterioration and hippocampal neuroplastic decline following NIHL are most likely driven by the maladaptive response of hippocampal microglia to myelin damage secondary to hearing loss, and we also demonstrated the potential of voluntary physical exercise as a promising and cost-effective strategy to alleviate the detrimental impact of APHL on cognitive function and thus curtail the high and continuously increasing global burden of dementia. Furthermore, the findings of the present study highlight the contribution of myelin debris overload to microglial malfunction and identify the microglial HIF1α-related pathway as an attractive candidate for future comprehensive investigation to obtain a more definitive picture of the underlying mechanisms linking APHL and dementia.
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Affiliation(s)
- Hong Zhuang
- Department of Physiology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Qian Li
- Department of Physiology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Congli Sun
- Department of Physiology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Dan Xu
- School of Public Health, Southeast University, Nanjing 210009, China
| | - Guangming Gan
- School of Medicine, Southeast University, Nanjing 210009, China
| | - Chenchen Zhang
- School of Medicine, Southeast University, Nanjing 210009, China
| | - Chen Chen
- School of Medicine, Southeast University, Nanjing 210009, China
| | - Yang Yuan
- Department of Endocrinology, Zhongda Hospital, Medical School, Southeast University, Nanjing 210009, China
| | - Linchen Liu
- Department of Rheumatology, Zhongda Hospital, School of Medicine, Southeast University, Nanjing 210009, China
| | - Yu Xiao
- Department of Physiology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Xiuting Yao
- Department of Physiology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Conghui Wang
- Department of Physiology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Xiaoming Kang
- School of Life Science and Technology, Southeast University, Nanjing 210009, China
| | - Chenxi Yang
- Department of Physiology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Jingyi Zhao
- School of Life Science and Technology, Southeast University, Nanjing 210009, China
| | - Wenhao Chen
- School of Medicine, Southeast University, Nanjing 210009, China
| | - Jiatang Wang
- School of Medicine, Southeast University, Nanjing 210009, China
| | - Jinyu Li
- School of Medicine, Southeast University, Nanjing 210009, China
| | - Caichen Luo
- School of Medicine, Southeast University, Nanjing 210009, China
| | - Jie Wang
- School of Medicine, Southeast University, Nanjing 210009, China
| | - Xirui Jia
- School of Life Science and Technology, Southeast University, Nanjing 210009, China
| | - Zhehao Yu
- Department of Physiology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Lijie Liu
- Jiangsu Provincial Key Laboratory of Critical Care Medicine, Department of Physiology, School of Medicine, Southeast University, Nanjing 210009, China.
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12
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Mesías RE, Zaki Y, Guevara CA, Friedman LG, Hussein A, Therrien K, Magee AR, Tzavaras N, Del Valle P, Baxter MG, Huntley GW, Benson DL. Development and cadherin-mediated control of prefrontal corticostriatal projections in mice. iScience 2023; 26:108002. [PMID: 37854688 PMCID: PMC10579443 DOI: 10.1016/j.isci.2023.108002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 08/07/2023] [Accepted: 09/18/2023] [Indexed: 10/20/2023] Open
Abstract
Action-outcome associations depend on prefrontal cortex (PFC) projections to the dorsal striatum. To assess how these projections form, we measured PFC axon patterning, synapse formation, and functional maturation in the postnatally developing mouse striatum. Using Hotspot analysis, we show that PFC axons form an adult-like pattern of clustered terminations in the first postnatal week that remains largely stable thereafter. PFC-striatal synaptic strength is adult-like by P21, while excitatory synapse density increases until adulthood. We then tested how the targeted deletion of a candidate adhesion/guidance protein, Cadherin-8 (Cdh8), from corticostriatal neurons regulates pathway development. Mutant mice showed diminished PFC axon targeting and reduced spontaneous glutamatergic synaptic activity in the dorsal striatum. They also exhibited impaired behavioral performance in action-outcome learning. The data show that PFC-striatal axons form striatal territories through an early, directed growth model and they highlight essential contributions of Cdh8 to the anatomical and functional features critical for the formation of action-outcome associations.
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Affiliation(s)
- Roxana E. Mesías
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Yosif Zaki
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Christopher A. Guevara
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Lauren G. Friedman
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Ayan Hussein
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Karen Therrien
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Alexandra R. Magee
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Nikolaos Tzavaras
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Pamela Del Valle
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Mark G. Baxter
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Section on Comparative Medicine, Department of Pathology, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
| | - George W. Huntley
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Deanna L. Benson
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
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13
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Shing K, Sapp E, Boudi A, Liu S, Seeley C, Marchionini D, DiFiglia M, Kegel-Gleason KB. Early whole-body mutant huntingtin lowering averts changes in proteins and lipids important for synapse function and white matter maintenance in the LacQ140 mouse model. Neurobiol Dis 2023; 187:106313. [PMID: 37777020 PMCID: PMC10731584 DOI: 10.1016/j.nbd.2023.106313] [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: 08/22/2023] [Revised: 09/25/2023] [Accepted: 09/27/2023] [Indexed: 10/02/2023] Open
Abstract
Expansion of a triplet repeat tract in exon 1 of the HTT gene causes Huntington's disease (HD). The mutant HTT protein (mHTT) has numerous aberrant interactions with diverse, pleiomorphic effects. Lowering mHTT is a promising approach to treat HD, but it is unclear when lowering should be initiated, how much is necessary, and what duration should occur to achieve benefits. Furthermore, the effects of mHTT lowering on brain lipids have not been assessed. Using a mHtt-inducible mouse model, we analyzed mHtt lowering initiated at different ages and sustained for different time-periods. mHTT protein in cytoplasmic and synaptic compartments of the striatum was reduced 38-52%; however, there was minimal lowering of mHTT in nuclear and perinuclear regions where aggregates formed at 12 months of age. Total striatal lipids were reduced in 9-month-old LacQ140 mice and preserved by mHtt lowering. Subclasses important for white matter structure and function including ceramide (Cer), sphingomyelin (SM), and monogalactosyldiacylglycerol (MGDG), contributed to the reduction in total lipids. Phosphatidylinositol (PI), phosphatidylserine (PS), and bismethyl phosphatidic acid (BisMePA) were also changed in LacQ140 mice. Levels of all subclasses except ceramide were preserved by mHtt lowering. mRNA expression profiling indicated that a transcriptional mechanism contributes to changes in myelin lipids, and some but not all changes can be prevented by mHtt lowering. Our findings suggest that early and sustained reduction in mHtt can prevent changes in levels of select striatal proteins and most lipids, but a misfolded, degradation-resistant form of mHTT hampers some benefits in the long term.
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Affiliation(s)
- Kai Shing
- Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129, USA
| | - Ellen Sapp
- Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129, USA
| | - Adel Boudi
- Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129, USA
| | - Sophia Liu
- Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129, USA
| | - Connor Seeley
- Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129, USA
| | | | - Marian DiFiglia
- Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129, USA
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14
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Seo JS, Lee SH, Won HS, Yang M, Nahm SS, Nam SM. Effects of Gestational and Lactational Lead Exposure and High Fat Diet Feeding on Cerebellar Development of Postnatal Rat Offspring. Nutrients 2023; 15:4325. [PMID: 37892401 PMCID: PMC10609260 DOI: 10.3390/nu15204325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 10/03/2023] [Accepted: 10/09/2023] [Indexed: 10/29/2023] Open
Abstract
Obesity and heavy metals, such as lead (Pb), are detrimental to the adult brain because they impair cognitive function and structural plasticity. However, the effects of co-administration of Pb and a high-fat diet (HFD) on the developing cerebellum is not clearly elucidated. We investigated the effects of Pb exposure (0.3% lead acetate) on developing cerebellum in the pups of an HFD-fed obese rat model. One week before mating, we fed a chow diet (CD) or HFD to the rats for one week and additionally administered Pb to HFD-fed female SD rats. Thereafter, treatment with Pb and a HFD was continued during the gestational and lactational periods. On postnatal day 21, the pups were euthanized to sample the brain tissue and blood for further analysis. Blood Pb levels were significantly higher in HFD-fed rats than in CD-fed rats. Histologically, the prominent degeneration of Purkinje cells was induced by the co-administration of Pb and HFD. The calbindin-28Kd-, GAD67-, NMDAR1-, and PSD95-immunopositive Purkinje cells and inhibitory synapse-forming pinceau structures were significantly decreased following Pb and HFD co-administration. MBP-immunoreactive myelinated axonal fibers were also impaired by HFD but were significantly damaged by the co-administration of HFD and Pb. Oxidative stress-related Nrf2-HO1 signaling was activated by HFD feeding, and Pb exposure further aggravated oxidative stress, as demonstrated by the consumption of endogenous anti-oxidant in HFD-Pb rats. The pro-inflammatory response was also increased by the co-administration of HFD and Pb in the cerebellum of the rat offspring. The present results suggest that HFD and Pb treatment during the gestational and lactational periods are harmful to cerebellar development.
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Affiliation(s)
- Jin Seok Seo
- Department of Anatomy, College of Veterinary Medicine, Konkuk University, Seoul 05029, Republic of Korea; (J.S.S.); (S.-S.N.)
| | - Shin Hyo Lee
- Department of Anatomy, School of Medicine and Jesaeng-Euise Clinical Anatomy Center, Wonkwang University, Iksan 54538, Republic of Korea; (S.H.L.); (H.-S.W.); (M.Y.)
| | - Hyung-Sun Won
- Department of Anatomy, School of Medicine and Jesaeng-Euise Clinical Anatomy Center, Wonkwang University, Iksan 54538, Republic of Korea; (S.H.L.); (H.-S.W.); (M.Y.)
| | - Miyoung Yang
- Department of Anatomy, School of Medicine and Jesaeng-Euise Clinical Anatomy Center, Wonkwang University, Iksan 54538, Republic of Korea; (S.H.L.); (H.-S.W.); (M.Y.)
| | - Sang-Seop Nahm
- Department of Anatomy, College of Veterinary Medicine, Konkuk University, Seoul 05029, Republic of Korea; (J.S.S.); (S.-S.N.)
| | - Sung Min Nam
- Department of Anatomy, School of Medicine and Jesaeng-Euise Clinical Anatomy Center, Wonkwang University, Iksan 54538, Republic of Korea; (S.H.L.); (H.-S.W.); (M.Y.)
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15
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González Ibáñez F, Halvorson T, Sharma K, McKee C, Carrier M, Picard K, Vernoux N, Bisht K, Deslauriers J, Lalowski M, Tremblay MÈ. Ketogenic diet alters microglial morphology and changes the hippocampal lipidomic profile distinctively in stress susceptible versus resistant male mice upon repeated social defeat. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.28.555135. [PMID: 37693370 PMCID: PMC10491121 DOI: 10.1101/2023.08.28.555135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
Psychological stress confers an increased risk for several diseases including psychiatric conditions. The susceptibility to psychological stress is modulated by various factors, many of them being modifiable lifestyle choices. The ketogenic diet (KD) has emerged as a dietary regime that offers positive outcomes on mood and health status. Psychological stress and elevated inflammation are common features of neuropsychiatric disorders such as certain types of major depressive disorder. KD has been attributed anti-inflammatory properties that could underlie its beneficial consequences on the brain and behavior. Microglia are the main drivers of inflammation in the central nervous system. They are known to respond to both dietary changes and psychological stress, notably by modifying their production of cytokines and relationships among the brain parenchyma. To assess the interactions between KD and the stress response, including effects on microglia, we examined adult male mice on control diet (CD) versus KD that underwent 10 days of repeated social defeat (RSD) or remained non-stressed (controls; CTRLs). Through a social interaction test, stressed mice were classified as susceptible (SUS) or resistant (RES) to RSD. The mouse population fed a KD tended to have a higher proportion of individuals classified as RES following RSD. Microglial morphology and ultrastructure were then analyzed in the ventral hippocampus CA1, a brain region known to present structural alterations as a response to psychological stress. Distinct changes in microglial soma and arborization linked to the KD, SUS and RES phenotypes were revealed. Ultrastructural analysis by electron microscopy showed a clear reduction of cellular stress markers in microglia from KD fed animals. Furthermore, ultrastructural analysis showed that microglial contacts with synaptic elements were reduced in the SUS compared to the RES and CTRL groups. Hippocampal lipidomic analyses lastly identified a distinct lipid profile in SUS animals compared to CTRLs. These key differences, combined with the distinct microglial responses to diet and stress, indicate that unique metabolic changes may underlie the stress susceptibility phenotypes. Altogether, our results reveal novel mechanisms by which a KD might improve the resistance to psychological stress.
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Affiliation(s)
- Fernando González Ibáñez
- Axe neurosciences, Centre de recherche du CHU de Québec-Université Laval, Québec, QC, Canada
- Département de médecine moléculaire, Université Laval, Québec City, QC, Canada
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
| | - Torin Halvorson
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
- Department of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Kaushik Sharma
- Axe neurosciences, Centre de recherche du CHU de Québec-Université Laval, Québec, QC, Canada
- Département de médecine moléculaire, Université Laval, Québec City, QC, Canada
- Department of Chemistry, Purdue University, West Lafayette, IN, United States of America
| | - Chloe McKee
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
| | - Micaël Carrier
- Axe neurosciences, Centre de recherche du CHU de Québec-Université Laval, Québec, QC, Canada
- Département de médecine moléculaire, Université Laval, Québec City, QC, Canada
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
| | - Katherine Picard
- Axe neurosciences, Centre de recherche du CHU de Québec-Université Laval, Québec, QC, Canada
- Département de médecine moléculaire, Université Laval, Québec City, QC, Canada
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
| | - Nathalie Vernoux
- Axe neurosciences, Centre de recherche du CHU de Québec-Université Laval, Québec, QC, Canada
| | - Kanchan Bisht
- Axe neurosciences, Centre de recherche du CHU de Québec-Université Laval, Québec, QC, Canada
- Département de médecine moléculaire, Université Laval, Québec City, QC, Canada
- Department of Chemistry, Purdue University, West Lafayette, IN, United States of America
| | | | - Maciej Lalowski
- Department of Gene Expression, Institute of Molecular Biology and Biotechnology, Faculty of Biology, Adam Mickiewicz University, Poznań, Poland
- Biochemistry/Developmental Biology, Meilahti Clinical Proteomics Core Facility, University of Helsinki, Finland
| | - Marie-Ève Tremblay
- Axe neurosciences, Centre de recherche du CHU de Québec-Université Laval, Québec, QC, Canada
- Département de médecine moléculaire, Université Laval, Québec City, QC, Canada
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
- Neurology and Neurosurgery Department, McGill University, Montréal, QC, Canada
- Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, BC, Canada
- Centre for Advanced Materials and Related Technology (CAMTEC), University of Victoria, BC, Canada
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16
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Shing K, Sapp E, Boudi A, Liu S, Seeley C, Marchionini D, DiFiglia M, Kegel-Gleason KB. Early whole-body mutant huntingtin lowering averts changes in proteins and lipids important for synapse function and white matter maintenance in the LacQ140 mouse model. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.26.525697. [PMID: 36747614 PMCID: PMC9900921 DOI: 10.1101/2023.01.26.525697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Expansion of a triplet repeat tract in exon1 of the HTT gene causes Huntington's disease (HD). The mutant HTT protein (mHTT) has numerous aberrant interactions with diverse, pleiomorphic effects. No disease modifying treatments exist but lowering mutant huntingtin (mHTT) by gene therapy is a promising approach to treat Huntington's disease (HD). It is not clear when lowering should be initiated, how much lowering is necessary and for what duration lowering should occur to achieve benefits. Furthermore, the effects of mHTT lowering on brain lipids have not been assessed. Using a mHtt-inducible mouse model we analyzed whole body mHtt lowering initiated at different ages and sustained for different time-periods. Subcellular fractionation (density gradient ultracentrifugation), protein chemistry (gel filtration, western blot, and capillary electrophoresis immunoassay), liquid chromatography and mass spectrometry of lipids, and bioinformatic approaches were used to test effects of mHTT transcriptional lowering. mHTT protein in cytoplasmic and synaptic compartments of the caudate putamen, which is most affected in HD, was reduced 38-52%. Little or no lowering of mHTT occurred in nuclear and perinuclear regions where aggregates formed at 12 months of age. mHtt transcript repression partially or fully preserved select striatal proteins (SCN4B, PDE10A). Total lipids in striatum were reduced in LacQ140 mice at 9 months and preserved by early partial mHtt lowering. The reduction in total lipids was due in part to reductions in subclasses of ceramide (Cer), sphingomyelin (SM), and monogalactosyldiacylglycerol (MGDG), which are known to be important for white matter structure and function. Lipid subclasses phosphatidylinositol (PI), phosphatidylserine (PS), and bismethyl phosphatidic acid (BisMePA) were also changed in LacQ140 mice. Levels of all subclasses other than ceramide were preserved by early mHtt lowering. Pathway enrichment analysis of RNAseq data imply a transcriptional mechanism is responsible in part for changes in myelin lipids, and some but not all changes can be rescued by mHTT lowering. Our findings suggest that early and sustained reduction in mHtt can prevent changes in levels of select striatal proteins and most lipids but a misfolded, degradation-resistant form of mHTT hampers some benefits in the long term.
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Affiliation(s)
- Kai Shing
- Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129
| | - Ellen Sapp
- Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129
| | - Adel Boudi
- Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129
| | - Sophia Liu
- Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129
| | - Connor Seeley
- Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129
| | | | - Marian DiFiglia
- Department of Neurology, Massachusetts General Hospital, Charlestown, MA 02129
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17
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Smriti, Singla M, Gupta S, Porwal O, Nasser Binjawhar D, Sayed AA, Mittal P, El-Demerdash FM, Algahtani M, Singh SK, Dua K, Gupta G, Bawa P, Altyar AE, Abdel-Daim MM. Theoretical design for covering Engeletin with functionalized nanostructure-lipid carriers as neuroprotective agents against Huntington's disease via the nasal-brain route. Front Pharmacol 2023; 14:1218625. [PMID: 37492081 PMCID: PMC10364480 DOI: 10.3389/fphar.2023.1218625] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Accepted: 06/26/2023] [Indexed: 07/27/2023] Open
Abstract
Objective: To propose a theoretical formulation of engeletin-nanostructured lipid nanocarriers for improved delivery and increased bioavailability in treating Huntington's disease (HD). Methods: We conducted a literature review of the pathophysiology of HD and the limitations of currently available medications. We also reviewed the potential therapeutic benefits of engeletin, a flavanol glycoside, in treating HD through the Keap1/nrf2 pathway. We then proposed a theoretical formulation of engeletin-nanostructured lipid nanocarriers for improved delivery across the blood-brain barrier (BBB) and increased bioavailability. Results: HD is an autosomal dominant neurological illness caused by a repetition of the cytosine-adenine-guanine trinucleotide, producing a mutant protein called Huntingtin, which degenerates the brain's motor and cognitive functions. Excitotoxicity, mitochondrial dysfunction, oxidative stress, elevated concentration of ROS and RNS, neuroinflammation, and protein aggregation significantly impact HD development. Current therapeutic medications can postpone HD symptoms but have long-term adverse effects when used regularly. Herbal medications such as engeletin have drawn attention due to their minimal side effects. Engeletin has been shown to reduce mitochondrial dysfunction and suppress inflammation through the Keap1/NRF2 pathway. However, its limited solubility and permeability hinder it from reaching the target site. A theoretical formulation of engeletin-nanostructured lipid nanocarriers may allow for free transit over the BBB due to offering a similar composition to the natural lipids present in the body a lipid solubility and increase bioavailability, potentially leading to a cure or prevention of HD. Conclusion: The theoretical formulation of engeletin-nanostructured lipid nanocarriers has the potential to improve delivery and increase the bioavailability of engeletin in the treatment of HD, which may lead to a cure or prevention of this fatal illness.
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Affiliation(s)
- Smriti
- Chitkara College of Pharmacy, Chitkara University, Rajpura, Punjab, India
| | - Madhav Singla
- Chitkara College of Pharmacy, Chitkara University, Rajpura, Punjab, India
| | - Saurabh Gupta
- Chameli Devi Institute of Pharmacy, Department of Pharmacology, Indore, Madhya Pradesh
| | - Omji Porwal
- Department of Pharmacognosy, Faculty of Pharmacy, Tishk International University, Erbil, Iraq
| | - Dalal Nasser Binjawhar
- Department of Chemistry, College of Science, Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabia
| | - Amany A. Sayed
- Zoology Department, Faculty of Science, Cairo University, Giza, Egypt
| | - Pooja Mittal
- Chitkara College of Pharmacy, Chitkara University, Rajpura, Punjab, India
| | - Fatma M. El-Demerdash
- Department of Environmental Studies, Institute of Graduate Studies and Research, Alexandria University, Alexandria, Egypt
| | - Mohammad Algahtani
- Department of Laboratory & Blood Bank, Security Forces Hospital, Mecca, Saudi Arabia
| | - Sachin Kumar Singh
- School of Pharmaceutical Sciences, Lovely Professional University, Phagwara, Punjab, India
- Australian Research Consortium in Complementary and Integrative Medicine, Faculty of Health, University of Technology Sydney, Ultimo, NSW, Australia
| | - Kamal Dua
- Australian Research Consortium in Complementary and Integrative Medicine, Faculty of Health, University of Technology Sydney, Ultimo, NSW, Australia
- Discipline of Pharmacy, Graduate School of Health, University of Technology Sydney, Ultimo, NSW, Australia
- Uttaranchal Institute of Pharmaceutical Sciences, Uttaranchal University, Dehradun, India
| | - Gaurav Gupta
- School of Pharmacy, Suresh Gyan Vihar University, Jaipur, India
- Center for Transdisciplinary Research, Saveetha Dental College, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, India
| | - Puneet Bawa
- Center of Excellence for Speech and Multimodel Laboratory, Institute of Engineering and Technology, Chitkara University, Rajpura, Punjab, India
| | - Ahmed E. Altyar
- Department of Pharmacy Practice, Faculty of Pharmacy, King Abdulaziz University, Jeddah, Saudi Arabia
- Pharmacy Program, Batterjee Medical College, Jeddah, Saudi Arabia
| | - Mohamed M. Abdel-Daim
- Department of Pharmaceutical Sciences, Pharmacy Program, Batterjee Medical College, Jeddah, Saudi Arabia
- Pharmacology Department, Faculty of Veterinary Medicine, Suez Canal University, Ismailia, Egypt
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18
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Zhang Z, Wiencke JK, Kelsey KT, Koestler DC, Molinaro AM, Pike SC, Karra P, Christensen BC, Salas LA. Hierarchical deconvolution for extensive cell type resolution in the human brain using DNA methylation. Front Neurosci 2023; 17:1198243. [PMID: 37404460 PMCID: PMC10315586 DOI: 10.3389/fnins.2023.1198243] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 05/30/2023] [Indexed: 07/06/2023] Open
Abstract
Introduction The human brain comprises heterogeneous cell types whose composition can be altered with physiological and pathological conditions. New approaches to discern the diversity and distribution of brain cells associated with neurological conditions would significantly advance the study of brain-related pathophysiology and neuroscience. Unlike single-nuclei approaches, DNA methylation-based deconvolution does not require special sample handling or processing, is cost-effective, and easily scales to large study designs. Existing DNA methylation-based methods for brain cell deconvolution are limited in the number of cell types deconvolved. Methods Using DNA methylation profiles of the top cell-type-specific differentially methylated CpGs, we employed a hierarchical modeling approach to deconvolve GABAergic neurons, glutamatergic neurons, astrocytes, microglial cells, oligodendrocytes, endothelial cells, and stromal cells. Results We demonstrate the utility of our method by applying it to data on normal tissues from various brain regions and in aging and diseased tissues, including Alzheimer's disease, autism, Huntington's disease, epilepsy, and schizophrenia. Discussion We expect that the ability to determine the cellular composition in the brain using only DNA from bulk samples will accelerate understanding brain cell type composition and cell-type-specific epigenetic states in normal and diseased brain tissues.
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Affiliation(s)
- Ze Zhang
- Department of Epidemiology, Geisel School of Medicine, Dartmouth College, Lebanon, NH, United States
| | - John K. Wiencke
- Department of Neurological Surgery, Institute for Human Genetics, University of California, San Francisco, San Francisco, CA, United States
| | - Karl T. Kelsey
- Department of Epidemiology, Department of Pathology and Laboratory Medicine, Brown University School of Public Health, Providence, RI, United States
| | - Devin C. Koestler
- Department of Biostatistics and Data Science, University of Kansas Medical Center, Kansas City, KS, United States
| | - Annette M. Molinaro
- Department of Neurological Surgery, Institute for Human Genetics, University of California, San Francisco, San Francisco, CA, United States
| | - Steven C. Pike
- Department of Epidemiology, Geisel School of Medicine, Dartmouth College, Lebanon, NH, United States
- Department of Neurology, Geisel School of Medicine, Dartmouth College, Lebanon, NH, United States
| | - Prasoona Karra
- Department of Epidemiology, Geisel School of Medicine, Dartmouth College, Lebanon, NH, United States
| | - Brock C. Christensen
- Department of Epidemiology, Geisel School of Medicine, Dartmouth College, Lebanon, NH, United States
- Department of Molecular and Systems Biology, Geisel School of Medicine, Dartmouth College, Lebanon, NH, United States
| | - Lucas A. Salas
- Department of Epidemiology, Geisel School of Medicine, Dartmouth College, Lebanon, NH, United States
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19
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Mesías RE, Zaki Y, Guevara CA, Friedman LG, Hussein A, Therrien K, Magee AR, Tzavaras N, Valle PD, Baxter MG, Huntley GW, Benson DL. Development of prefrontal corticostriatal connectivity in mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.14.532475. [PMID: 36993639 PMCID: PMC10054964 DOI: 10.1101/2023.03.14.532475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Rational decision making is grounded in learning to associate actions with outcomes, a process that depends on projections from prefrontal cortex to dorsomedial striatum. Symptoms associated with a variety of human pathological conditions ranging from schizophrenia and autism to Huntington's and Parkinson's disease point toward functional deficits in this projection, but its development is not well understood, making it difficult to investigate how perturbations in development of this circuitry could contribute to pathophysiology. We applied a novel strategy based on Hotspot Analysis to assess the developmental progression of anatomical positioning of prefrontal cortex to striatal projections. Corticostriatal axonal territories established at P7 expand in concert with striatal growth but remain largely unchanged in positioning through adulthood, indicating they are generated by directed, targeted growth and not modified extensively by postnatal experience. Consistent with these findings, corticostriatal synaptogenesis increased steadily from P7 to P56, with no evidence for widescale pruning. As corticostriatal synapse density increased over late postnatal ages, the strength of evoked PFC input onto dorsomedial striatal projection neurons also increased, but spontaneous glutamatergic synaptic activity was stable. Based on its pattern of expression, we asked whether the adhesion protein, Cdh8, influenced this progression. In mice lacking Cdh8 in PFC corticostriatal projection neurons, axon terminal fields in dorsal striatum shifted ventrally. Corticostriatal synaptogenesis was unimpeded, but spontaneous EPSC frequency declined and mice failed to learn to associate an action with an outcome. Collectively these findings show that corticostriatal axons grow to their target zone and are restrained from an early age, do not undergo postnatal synapse pruning as the most dominant models predict, and that a relatively modest shift in terminal arbor positioning and synapse function has an outsized, negative impact on corticostriatal-dependent behavior.
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20
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St-Pierre MK, Carrier M, González Ibáñez F, Khakpour M, Wallman MJ, Parent M, Tremblay MÈ. Astrocytes display ultrastructural alterations and heterogeneity in the hippocampus of aged APP-PS1 mice and human post-mortem brain samples. J Neuroinflammation 2023; 20:73. [PMID: 36918925 PMCID: PMC10015698 DOI: 10.1186/s12974-023-02752-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 02/24/2023] [Indexed: 03/16/2023] Open
Abstract
The past decade has witnessed increasing evidence for a crucial role played by glial cells, notably astrocytes, in Alzheimer's disease (AD). To provide novel insights into the roles of astrocytes in the pathophysiology of AD, we performed a quantitative ultrastructural characterization of their intracellular contents and parenchymal interactions in an aged mouse model of AD pathology, as aging is considered the main risk factor for developing AD. We compared 20-month-old APP-PS1 and age-matched C57BL/6J male mice, among the ventral hippocampus CA1 strata lacunosum-moleculare and radiatum, two hippocampal layers severely affected by AD pathology. Astrocytes in both layers interacted more with synaptic elements and displayed more ultrastructural markers of increased phagolysosomal activity in APP-PS1 versus C57BL6/J mice. In addition, we investigated the ultrastructural heterogeneity of astrocytes, describing in the two examined layers a dark astrocytic state that we characterized in terms of distribution, interactions with AD hallmarks, and intracellular contents. This electron-dense astrocytic state, termed dark astrocytes, was observed throughout the hippocampal parenchyma, closely associated with the vasculature, and possessed several ultrastructural markers of cellular stress. A case study exploring the hippocampal head of an aged human post-mortem brain sample also revealed the presence of a similar electron-dense, dark astrocytic state. Overall, our study provides the first ultrastructural quantitative analysis of astrocytes among the hippocampus in aged AD pathology, as well as a thorough characterization of a dark astrocytic state conserved from mouse to human.
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Affiliation(s)
- Marie-Kim St-Pierre
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, QC, Canada.,Départment de Médecine Moléculaire, Faculté de Médecine, Université Laval, Québec, QC, Canada.,Division of Medical Sciences, Medical Sciences Building, University of Victoria, Victoria, BC, Canada
| | - Micaël Carrier
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, QC, Canada.,Division of Medical Sciences, Medical Sciences Building, University of Victoria, Victoria, BC, Canada
| | - Fernando González Ibáñez
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, QC, Canada.,Départment de Médecine Moléculaire, Faculté de Médecine, Université Laval, Québec, QC, Canada.,Division of Medical Sciences, Medical Sciences Building, University of Victoria, Victoria, BC, Canada
| | - Mohammadparsa Khakpour
- Division of Medical Sciences, Medical Sciences Building, University of Victoria, Victoria, BC, Canada
| | - Marie-Josée Wallman
- Département de Psychiatrie et de Neurosciences, Faculté de Médecine, Université Laval, Québec, QC, Canada.,CERVO Brain Research Center, Quebec City, QC, Canada
| | - Martin Parent
- Département de Psychiatrie et de Neurosciences, Faculté de Médecine, Université Laval, Québec, QC, Canada.,CERVO Brain Research Center, Quebec City, QC, Canada
| | - Marie-Ève Tremblay
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, QC, Canada. .,Départment de Médecine Moléculaire, Faculté de Médecine, Université Laval, Québec, QC, Canada. .,Division of Medical Sciences, Medical Sciences Building, University of Victoria, Victoria, BC, Canada. .,Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC, Canada. .,Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada. .,Centre for Advanced Materials and Related Technology (CAMTEC), University of Victoria, Victoria, BC, Canada. .,Institute on Aging and Lifelong Health, University of Victoria, Victoria, BC, Canada.
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21
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Niraula A, Fasnacht RD, Ness KM, Frey JM, Cuschieri SA, Dorfman MD, Thaler JP. Prostaglandin PGE2 Receptor EP4 Regulates Microglial Phagocytosis and Increases Susceptibility to Diet-Induced Obesity. Diabetes 2023; 72:233-244. [PMID: 36318114 PMCID: PMC10090268 DOI: 10.2337/db21-1072] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 10/23/2022] [Indexed: 11/06/2022]
Abstract
In rodents, susceptibility to diet-induced obesity requires microglial activation, but the molecular components of this pathway remain incompletely defined. Prostaglandin PGE2 levels increase in the mediobasal hypothalamus during high-fat-diet (HFD) feeding, and the PGE2 receptor EP4 regulates microglial activation state and phagocytic activity, suggesting a potential role for microglial EP4 signaling in obesity pathogenesis. To test the role of microglial EP4 in energy balance regulation, we analyzed the metabolic phenotype in a microglia-specific EP4 knockout (MG-EP4 KO) mouse model. Microglial EP4 deletion markedly reduced weight gain and food intake in response to HFD feeding. Corresponding with this lean phenotype, insulin sensitivity was also improved in HFD-fed MG-EP4 KO mice, though glucose tolerance remained surprisingly unaffected. Mechanistically, EP4-deficient microglia showed an attenuated phagocytic state marked by reduced CD68 expression and fewer contacts with pro-opiomelanocortin (POMC) neuron processes. These cellular changes observed in the MG-EP4 KO mice corresponded with an increased density of POMC neurites extending into the paraventricular nucleus (PVN). These findings reveal that microglial EP4 signaling promotes body weight gain and insulin resistance during HFD feeding. Furthermore, the data suggest that curbing microglial phagocytic function may preserve POMC cytoarchitecture and PVN input to limit overconsumption during diet-induced obesity.
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Affiliation(s)
- Anzela Niraula
- UW Medicine Diabetes Institute, University of Washington, Seattle, WA
- Department of Medicine, University of Washington, Seattle, WA
| | - Rachael D. Fasnacht
- UW Medicine Diabetes Institute, University of Washington, Seattle, WA
- Department of Medicine, University of Washington, Seattle, WA
| | - Kelly M. Ness
- UW Medicine Diabetes Institute, University of Washington, Seattle, WA
- Department of Medicine, University of Washington, Seattle, WA
| | - Jeremy M. Frey
- UW Medicine Diabetes Institute, University of Washington, Seattle, WA
- Department of Medicine, University of Washington, Seattle, WA
| | - Sophia A. Cuschieri
- UW Medicine Diabetes Institute, University of Washington, Seattle, WA
- Department of Medicine, University of Washington, Seattle, WA
| | - Mauricio D. Dorfman
- UW Medicine Diabetes Institute, University of Washington, Seattle, WA
- Department of Medicine, University of Washington, Seattle, WA
| | - Joshua P. Thaler
- UW Medicine Diabetes Institute, University of Washington, Seattle, WA
- Department of Medicine, University of Washington, Seattle, WA
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22
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St-Pierre MK, Šimončičová E, Carrier M, Tremblay MÈ. Microglia in Human Postmortem Brain Samples: Quantitative Ultrastructural Analysis of Scanning Electron Microscopy Images. Methods Mol Biol 2023; 2561:63-85. [PMID: 36399265 DOI: 10.1007/978-1-0716-2655-9_4] [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] [Indexed: 06/16/2023]
Abstract
In this protocol, we describe the specific steps required to prepare human postmortem brain samples for ultrastructural microglial analysis. A detailed procedure is provided to improve the ultrastructural quality of the samples, using aldehyde fixatives followed by immunoperoxidase staining of allograft inflammatory factor 1 (AIF1, also known as IBA1), a marker of myeloid cells, and cluster of differentiation 68 (CD68), a marker of phagolysosomal activity. Additionally, we describe an osmium-thiocarbohydrazide-osmium (OTO) post-fixation method that preserves and increases the contrast of cellular membranes in human postmortem brain samples, as well as the steps necessary to acquire scanning electron microscopy (SEM) images of microglial cell bodies. In the last section, we cover the quantitative analysis of various microglial cytoplasmic organelles and their interactions with other parenchymal elements.
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Affiliation(s)
- Marie-Kim St-Pierre
- Axe neurosciences, Centre de recherche du CHU de Québec-Université Laval, Québec, QC, Canada
- Département de médecine moléculaire, Faculté de médecine, Université Laval, Québec, QC, Canada
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
| | - Eva Šimončičová
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
- Neuroscience Graduate Program, University of Victoria, Victoria, Canada
| | - Micaël Carrier
- Axe neurosciences, Centre de recherche du CHU de Québec-Université Laval, Québec, QC, Canada
- Département de médecine moléculaire, Faculté de médecine, Université Laval, Québec, QC, Canada
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
| | - Marie-Ève Tremblay
- Axe neurosciences, Centre de recherche du CHU de Québec-Université Laval, Québec, QC, Canada.
- Département de médecine moléculaire, Faculté de médecine, Université Laval, Québec, QC, Canada.
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada.
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC, Canada.
- Department of Neurology and Neurosurgery, McGill University, Montréal, QC, Canada.
- Centre for Advanced Materials and Related Technology (CAMTEC), University of Victoria, Victoria, Canada.
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23
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Elbandy M. Anti-Inflammatory Effects of Marine Bioactive Compounds and Their Potential as Functional Food Ingredients in the Prevention and Treatment of Neuroinflammatory Disorders. MOLECULES (BASEL, SWITZERLAND) 2022; 28:molecules28010002. [PMID: 36615197 PMCID: PMC9822486 DOI: 10.3390/molecules28010002] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 12/13/2022] [Accepted: 12/15/2022] [Indexed: 12/24/2022]
Abstract
Functional foods include enhanced, enriched, fortified, or whole foods that impart health benefits beyond their nutritional value, particularly when consumed as part of a varied diet on a regular basis at effective levels. Marine sources can serve as the sources of various healthy foods and numerous functional food ingredients with biological effects can be derived from these sources. Microalgae, macroalgae, crustaceans, fungi, bacteria fish, and fish by-products are the most common marine sources that can provide many potential functional food ingredients including phenolic compounds, proteins and peptides, and polysaccharides. Neuroinflammation is closely linked with the initiation and progression of various neurodegenerative diseases, including Alzheimer's disease, Huntington's disease, and Parkinson's disease. Activation of astrocytes and microglia is a defense mechanism of the brain to counter damaged tissues and detrimental pathogens, wherein their chronic activation triggers neuroinflammation that can further exacerbate or induce neurodegeneration. Currently, available therapeutic agents only provide symptomatic relief from these disorders and no therapies are available to stop or slow down the advancement of neurodegeneration. Thereffore, natural compounds that can exert a protective effect against these disorders have therapeutic potential. Numerous chemical compounds, including bioactive peptides, fatty acids, pigments, alkaloids, and polysaccharides, have already been isolated from marine sources that show anti-inflammatory properties, which can be effective in the treatment and prevention of neuroinflammatory disorders. The anti-inflammatory potential of marine-derived compounds as functional food ingredients in the prevention and treatment of neurological disorders is covered in this review.
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Affiliation(s)
- Mohamed Elbandy
- Department of Clinical Nutrition, College of Applied Medical Science, Jazan University, Jazan 45142, Saudi Arabia
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24
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Cohen LD, Ziv T, Ziv NE. Synapse integrity and function: Dependence on protein synthesis and identification of potential failure points. Front Mol Neurosci 2022; 15:1038614. [PMID: 36583084 PMCID: PMC9792512 DOI: 10.3389/fnmol.2022.1038614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 11/07/2022] [Indexed: 12/14/2022] Open
Abstract
Synaptic integrity and function depend on myriad proteins - labile molecules with finite lifetimes that need to be continually replaced with freshly synthesized copies. Here we describe experiments designed to expose synaptic (and neuronal) properties and functions that are particularly sensitive to disruptions in protein supply, identify proteins lost early upon such disruptions, and uncover potential, yet currently underappreciated failure points. We report here that acute suppressions of protein synthesis are followed within hours by reductions in spontaneous network activity levels, impaired oxidative phosphorylation and mitochondrial function, and, importantly, destabilization and loss of both excitatory and inhibitory postsynaptic specializations. Conversely, gross impairments in presynaptic vesicle recycling occur over longer time scales (days), as does overt cell death. Proteomic analysis identified groups of potentially essential 'early-lost' proteins including regulators of synapse stability, proteins related to bioenergetics, fatty acid and lipid metabolism, and, unexpectedly, numerous proteins involved in Alzheimer's disease pathology and amyloid beta processing. Collectively, these findings point to neuronal excitability, energy supply and synaptic stability as early-occurring failure points under conditions of compromised supply of newly synthesized protein copies.
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Affiliation(s)
- Laurie D. Cohen
- Technion Faculty of Medicine, Rappaport Institute and Network Biology Research Laboratories, Haifa, Israel
| | - Tamar Ziv
- Smoler Proteomics Center, Lokey Interdisciplinary Center for Life Sciences & Engineering, Technion, Haifa, Israel
| | - Noam E. Ziv
- Technion Faculty of Medicine, Rappaport Institute and Network Biology Research Laboratories, Haifa, Israel,*Correspondence: Noam E. Ziv,
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25
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Wu J, Möhle L, Brüning T, Eiriz I, Rafehi M, Stefan K, Stefan SM, Pahnke J. A Novel Huntington's Disease Assessment Platform to Support Future Drug Discovery and Development. Int J Mol Sci 2022; 23:ijms232314763. [PMID: 36499090 PMCID: PMC9740291 DOI: 10.3390/ijms232314763] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 11/21/2022] [Accepted: 11/22/2022] [Indexed: 11/29/2022] Open
Abstract
Huntington's disease (HD) is a lethal neurodegenerative disorder without efficient therapeutic options. The inefficient translation from preclinical and clinical research into clinical use is mainly attributed to the lack of (i) understanding of disease initiation, progression, and involved molecular mechanisms; (ii) knowledge of the possible HD target space and general data awareness; (iii) detailed characterizations of available disease models; (iv) better suitable models; and (v) reliable and sensitive biomarkers. To generate robust HD-like symptoms in a mouse model, the neomycin resistance cassette was excised from zQ175 mice, generating a new line: zQ175Δneo. We entirely describe the dynamics of behavioral, neuropathological, and immunohistological changes from 15-57 weeks of age. Specifically, zQ175Δneo mice showed early astrogliosis from 15 weeks; growth retardation, body weight loss, and anxiety-like behaviors from 29 weeks; motor deficits and reduced muscular strength from 36 weeks; and finally slight microgliosis at 57 weeks of age. Additionally, we collected the entire bioactivity network of small-molecule HD modulators in a multitarget dataset (HD_MDS). Hereby, we uncovered 358 unique compounds addressing over 80 different pharmacological targets and pathways. Our data will support future drug discovery approaches and may serve as useful assessment platform for drug discovery and development against HD.
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Affiliation(s)
- Jingyun Wu
- Department of Pathology, Section of Neuropathology, Translational Neurodegeneration Research and Neuropathology Lab, University of Oslo and Oslo University Hospital, Sognsvannsveien 20, 0372 Oslo, Norway; www.pahnkelab.eu
| | - Luisa Möhle
- Department of Pathology, Section of Neuropathology, Translational Neurodegeneration Research and Neuropathology Lab, University of Oslo and Oslo University Hospital, Sognsvannsveien 20, 0372 Oslo, Norway; www.pahnkelab.eu
| | - Thomas Brüning
- Department of Pathology, Section of Neuropathology, Translational Neurodegeneration Research and Neuropathology Lab, University of Oslo and Oslo University Hospital, Sognsvannsveien 20, 0372 Oslo, Norway; www.pahnkelab.eu
| | - Iván Eiriz
- Department of Pathology, Section of Neuropathology, Translational Neurodegeneration Research and Neuropathology Lab, University of Oslo and Oslo University Hospital, Sognsvannsveien 20, 0372 Oslo, Norway; www.pahnkelab.eu
| | - Muhammad Rafehi
- Institute of Clinical Pharmacology, University Medical Center Göttingen, Robert-Koch-Str. 40, 37075 Göttingen, Germany
| | - Katja Stefan
- Department of Pathology, Section of Neuropathology, Translational Neurodegeneration Research and Neuropathology Lab, University of Oslo and Oslo University Hospital, Sognsvannsveien 20, 0372 Oslo, Norway; www.pahnkelab.eu
| | - Sven Marcel Stefan
- Department of Pathology, Section of Neuropathology, Translational Neurodegeneration Research and Neuropathology Lab, University of Oslo and Oslo University Hospital, Sognsvannsveien 20, 0372 Oslo, Norway; www.pahnkelab.eu
- Pahnke Lab (Drug Development and Chemical Biology), Lübeck Institute of Experimental Dermatology (LIED), University of Lübeck and University Medical Center Schleswig-Holstein, Ratzeburger Allee 160, 23538 Lübeck, Germany
- Correspondence: (J.P.); (S.M.S.); Tel.: +47-23-071-466 (J.P.)
| | - Jens Pahnke
- Department of Pathology, Section of Neuropathology, Translational Neurodegeneration Research and Neuropathology Lab, University of Oslo and Oslo University Hospital, Sognsvannsveien 20, 0372 Oslo, Norway; www.pahnkelab.eu
- Pahnke Lab (Drug Development and Chemical Biology), Lübeck Institute of Experimental Dermatology (LIED), University of Lübeck and University Medical Center Schleswig-Holstein, Ratzeburger Allee 160, 23538 Lübeck, Germany
- Department of Pharmacology, Faculty of Medicine, University of Latvia, Jelgavas iela 4, 1004 Rīga, Latvia
- Department of Neurobiology, The Georg S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 6997801, Israel
- Correspondence: (J.P.); (S.M.S.); Tel.: +47-23-071-466 (J.P.)
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26
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Garofalo S, Cocozza G, Bernardini G, Savage J, Raspa M, Aronica E, Tremblay ME, Ransohoff RM, Santoni A, Limatola C. Blocking immune cell infiltration of the central nervous system to tame Neuroinflammation in Amyotrophic lateral sclerosis. Brain Behav Immun 2022; 105:1-14. [PMID: 35688338 DOI: 10.1016/j.bbi.2022.06.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 04/29/2022] [Accepted: 06/05/2022] [Indexed: 12/14/2022] Open
Abstract
Neuroinflammation is one of the main hallmarks of amyotrophic lateral sclerosis (ALS). Recently, peripheral immune cells were discovered as pivotal players that promptly participate in this process, speeding up neurodegeneration during progression of the disease. In particular, infiltrating T cells and natural killer cells release inflammatory cytokines that switch glial cells toward a pro-inflammatory/detrimental phenotype, and directly attack motor neurons with specific ligand-receptor signals. Here, we assessed the presence of lymphocytes in the spinal cord of sporadic ALS patients. Furthermore, we demonstrate that blocking the extravasation of immune cells in the central nervous system using Natalizumab (NAT), an antibody for the α4 integrin, reduces the level of interferon-γ in the spinal cord of ALS mouse models, such as the hSOD1G93A and TDP43A315T mice, modifying microglia and astrocytes phenotype, increasing motor neuron number and prolonging the survival time. Taken together, our results establish a central role for the immune cells as drivers of inflammation in ALS.
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Affiliation(s)
- Stefano Garofalo
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy.
| | | | - Giovanni Bernardini
- Department of Molecular Medicine, Laboratory Affiliated to Istituto Pasteur Italia, Sapienza University of Rome, Rome, Italy
| | - Julie Savage
- Division of Medical Sciences, University of Victoria Victoria, Canada
| | | | - Eleonora Aronica
- Amsterdam UMC Location University of Amsterdam, Department of (Neuro)Pathology Amsterdam Neuroscience, Meibergdreef 9, Amsterdam, the Netherlands
| | | | | | | | - Cristina Limatola
- IRCCS Neuromed Pozzilli, Italy; Department of Physiology and Pharmacology, Sapienza University, Laboratory affiliated to Istituto Pasteur, Italia.
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27
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St-Pierre MK, Carrier M, González Ibáñez F, Šimončičová E, Wallman MJ, Vallières L, Parent M, Tremblay MÈ. Ultrastructural characterization of dark microglia during aging in a mouse model of Alzheimer's disease pathology and in human post-mortem brain samples. J Neuroinflammation 2022; 19:235. [PMID: 36167544 PMCID: PMC9513936 DOI: 10.1186/s12974-022-02595-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2022] [Accepted: 09/12/2022] [Indexed: 11/10/2022] Open
Abstract
A diverse heterogeneity of microglial cells was previously described in Alzheimer's disease (AD) pathology, including dark microglia, a state characterized by ultrastructural markers of cellular stress. To provide novel insights into the roles of dark microglia during aging in the context of AD pathology, we performed a quantitative density and ultrastructural analysis of these cells using high-throughput scanning electron microscopy in the ventral hippocampus CA1 stratum lacunosum-moleculare of 20-month-old APP-PS1 vs C57BL/6J male mice. The density of dark microglia was significantly higher in APP-PS1 vs C57BL/6J mice, with these cells accounting for nearly half of all microglia observed near amyloid-beta (Aβ) plaques. This dark microglial state interacted more with dystrophic neurites compared to other APP-PS1 microglia and possessed glycogen granules, associated with a metabolic shift toward glycolysis, which provides the first ultrastructural evidence of their presence in microglia. Dark microglia were further observed in aging human post-mortem brain samples showing similar ultrastructural features as in mouse. Overall, our results provide a quantitative ultrastructural characterization of a microglial state associated with cellular stress (i.e., dark microglia) that is primarily restricted near Aβ plaques and dystrophic neurites. The presence of this microglial state in the aging human post-mortem brain is further revealed.
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Affiliation(s)
- Marie-Kim St-Pierre
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, QC, Canada.,Department of Molecular Medicine, Université Laval, Québec City, QC, Canada.,Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
| | - Micaël Carrier
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, QC, Canada.,Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
| | - Fernando González Ibáñez
- Department of Molecular Medicine, Université Laval, Québec City, QC, Canada.,Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
| | - Eva Šimončičová
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada.,Neuroscience Graduate Program, University of Victoria, Victoria, BC, Canada
| | - Marie-Josée Wallman
- Département de Psychiatrie et de Neurosciences, Faculté de Médecine, Université Laval, Quebec, QC, Canada.,CERVO Brain Research Center, Quebec, QC, Canada
| | - Luc Vallières
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, QC, Canada.,Department of Molecular Medicine, Université Laval, Québec City, QC, Canada
| | - Martin Parent
- Département de Psychiatrie et de Neurosciences, Faculté de Médecine, Université Laval, Quebec, QC, Canada.,CERVO Brain Research Center, Quebec, QC, Canada
| | - Marie-Ève Tremblay
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, QC, Canada. .,Department of Molecular Medicine, Université Laval, Québec City, QC, Canada. .,Division of Medical Sciences, University of Victoria, Victoria, BC, Canada. .,Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, BC, Canada. .,Department of Neurology and Neurosurgery, McGill University, Montréal, QC, Canada. .,Centre for Advanced Materials and Related Technology (CAMTEC), University of Victoria, Victoria, BC, Canada.
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28
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A 3D analysis revealed complexe mitochondria morphologies in porcine cumulus cells. Sci Rep 2022; 12:15403. [PMID: 36100690 PMCID: PMC9470746 DOI: 10.1038/s41598-022-19723-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 09/02/2022] [Indexed: 11/09/2022] Open
Abstract
In the ovarian follicle, a bilateral cell-to-cell communication exists between the female germ cell and the cumulus cells which surround the oocyte. This communication allows the transit of small size molecules known to impact oocyte developmental competence. Pyruvate derivatives produced by mitochondria, are one of these transferred molecules. Interestingly, mitochondria may adopt a variety of morphologies to regulate their functions. In this study, we described mitochondrial morphologies in porcine cumulus cells. Active mitochondria were stained with TMRM (Tetramethylrhodamine, Methyl Ester, Perchlorate) and observed with 2D confocal microscopy showing mitochondria of different morphologies such as short, intermediate, long, and very long. The number of mitochondria of each phenotype was quantified in cells and the results showed that most cells contained elongated mitochondria. Scanning electron microscopy (SEM) analysis confirmed at nanoscale resolution the different mitochondrial morphologies including round, short, intermediate, and long. Interestingly, 3D visualisation by focused ion-beam scanning electron microscopy (FIB-SEM) revealed different complex mitochondrial morphologies including connected clusters of different sizes, branched mitochondria, as well as individual mitochondria. Since mitochondrial dynamics is a key regulator of function, the description of the mitochondrial network organisation will allow to further study mitochondrial dynamics in cumulus cells in response to various conditions such as in vitro maturation.
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29
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St-Pierre MK, Carrier M, Lau V, Tremblay MÈ. Investigating Microglial Ultrastructural Alterations and Intimate Relationships with Neuronal Stress, Dystrophy, and Degeneration in Mouse Models of Alzheimer's Disease. METHODS IN MOLECULAR BIOLOGY (CLIFTON, N.J.) 2022; 2515:29-58. [PMID: 35776344 DOI: 10.1007/978-1-0716-2409-8_3] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
In recent decades, microglia have taken the field of neuroscience by storm, with numerous studies identifying key roles for these cells in the pathophysiology of neurodegenerative conditions, such as Alzheimer's disease (AD). The heterogeneity of these cells (e.g., the presence of various subtypes like the disease-associated microglia, microglia associated with neurodegeneration, dark microglia, lipid droplet-accumulating microglia), and their ultrastructural alterations arising from environmental challenges have become a central focus of recent studies. Dark microglia are electron-dense cells defined by their ultrastructural markers of cellular stress using electron microscopy (EM). In this protocol, we first describe the steps required for proper brain tissue preparation for EM experiments. Ultrastructural analysis of microglia and neurons/synapses in AD mouse models is also detailed, using transmission or scanning EM. We next explain how to characterize several ultrastructural markers of cellular stress, dystrophy or degeneration, in microglia and neurons/synapses, with relation to amyloid beta plaques.
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Affiliation(s)
- Marie-Kim St-Pierre
- Axe neurosciences, Centre de recherche du CHU de Québec-Université Laval, Québec, QC, Canada.,Département de médecine moléculaire, Faculté de médecine, Université Laval, Québec, QC, Canada.,Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
| | - Micaël Carrier
- Axe neurosciences, Centre de recherche du CHU de Québec-Université Laval, Québec, QC, Canada.,Division of Medical Sciences, University of Victoria, Victoria, BC, Canada.,Département de neurosciences, Faculté de médecine, Université Laval, Québec, QC, Canada
| | - Victor Lau
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada.,Department of Biomedical Physiology & Kinesiology, Simon Fraser University, Victoria, BC, Canada
| | - Marie-Ève Tremblay
- Axe neurosciences, Centre de recherche du CHU de Québec-Université Laval, Québec, QC, Canada. .,Département de médecine moléculaire, Faculté de médecine, Université Laval, Québec, QC, Canada. .,Division of Medical Sciences, University of Victoria, Victoria, BC, Canada. .,The Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, BC, Canada. .,Department of Neurology and Neurosurgery, McGill University, Montréal, QC, Canada. .,Centre for Advanced Materials and Related Technology (CAMTEC), University of Victoria , Victoria, Canada.
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30
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Molecular Pathophysiological Mechanisms in Huntington's Disease. Biomedicines 2022; 10:biomedicines10061432. [PMID: 35740453 PMCID: PMC9219859 DOI: 10.3390/biomedicines10061432] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 06/12/2022] [Accepted: 06/14/2022] [Indexed: 12/11/2022] Open
Abstract
Huntington’s disease is an inherited neurodegenerative disease described 150 years ago by George Huntington. The genetic defect was identified in 1993 to be an expanded CAG repeat on exon 1 of the huntingtin gene located on chromosome 4. In the following almost 30 years, a considerable amount of research, using mainly animal models or in vitro experiments, has tried to unravel the complex molecular cascades through which the transcription of the mutant protein leads to neuronal loss, especially in the medium spiny neurons of the striatum, and identified excitotoxicity, transcriptional dysregulation, mitochondrial dysfunction, oxidative stress, impaired proteostasis, altered axonal trafficking and reduced availability of trophic factors to be crucial contributors. This review discusses the pathogenic cascades described in the literature through which mutant huntingtin leads to neuronal demise. However, due to the ubiquitous presence of huntingtin, astrocytes are also dysfunctional, and neuroinflammation may additionally contribute to Huntington’s disease pathology. The quest for therapies to delay the onset and reduce the rate of Huntington’s disease progression is ongoing, but is based on findings from basic research.
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31
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Saba J, Couselo FL, Bruno J, Carniglia L, Durand D, Lasaga M, Caruso C. Neuroinflammation in Huntington's Disease: A Starring Role for Astrocyte and Microglia. Curr Neuropharmacol 2022; 20:1116-1143. [PMID: 34852742 PMCID: PMC9886821 DOI: 10.2174/1570159x19666211201094608] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 10/06/2021] [Accepted: 11/26/2021] [Indexed: 11/22/2022] Open
Abstract
Huntington's disease (HD) is a neurodegenerative genetic disorder caused by a CAG repeat expansion in the huntingtin gene. HD causes motor, cognitive, and behavioral dysfunction. Since no existing treatment affects the course of this disease, new treatments are needed. Inflammation is frequently observed in HD patients before symptom onset. Neuroinflammation, characterized by the presence of reactive microglia, astrocytes and inflammatory factors within the brain, is also detected early. However, in comparison to other neurodegenerative diseases, the role of neuroinflammation in HD is much less known. Work has been dedicated to altered microglial and astrocytic functions in the context of HD, but less attention has been given to glial participation in neuroinflammation. This review describes evidence of inflammation in HD patients and animal models. It also discusses recent knowledge on neuroinflammation in HD, highlighting astrocyte and microglia involvement in the disease and considering anti-inflammatory therapeutic approaches.
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Affiliation(s)
- Julieta Saba
- Instituto de Investigaciones Biomédicas (INBIOMED), UBA-CONICET, Paraguay 2155, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Federico López Couselo
- Instituto de Investigaciones Biomédicas (INBIOMED), UBA-CONICET, Paraguay 2155, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Julieta Bruno
- Instituto de Investigaciones Biomédicas (INBIOMED), UBA-CONICET, Paraguay 2155, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Lila Carniglia
- Instituto de Investigaciones Biomédicas (INBIOMED), UBA-CONICET, Paraguay 2155, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Daniela Durand
- Instituto de Investigaciones Biomédicas (INBIOMED), UBA-CONICET, Paraguay 2155, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Mercedes Lasaga
- Instituto de Investigaciones Biomédicas (INBIOMED), UBA-CONICET, Paraguay 2155, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Carla Caruso
- Instituto de Investigaciones Biomédicas (INBIOMED), UBA-CONICET, Paraguay 2155, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina,Address correspondence to this author at the Instituto de Investigaciones Biomédicas (INBIOMED), UBA-CONICET, Paraguay 2155 Piso 10, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina, Tel: +54 11 5285 3380; E-mail:
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32
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Kacher R, Mounier C, Caboche J, Betuing S. Altered Cholesterol Homeostasis in Huntington’s Disease. Front Aging Neurosci 2022; 14:797220. [PMID: 35517051 PMCID: PMC9063567 DOI: 10.3389/fnagi.2022.797220] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Accepted: 03/18/2022] [Indexed: 12/25/2022] Open
Abstract
Huntington’s disease (HD) is an autosomal dominant genetic disorder caused by an expansion of the CAG repeat in the first exon of Huntingtin’s gene. The associated neurodegeneration mainly affects the striatum and the cortex at early stages and progressively spreads to other brain structures. Targeting HD at its earlier stages is under intense investigation. Numerous drugs were tested, with a rate of success of only 3.5% approved molecules used as symptomatic treatment. The restoration of cholesterol metabolism, which is central to the brain homeostasis and strongly altered in HD, could be an interesting disease-modifying strategy. Cholesterol is an essential membrane component in the central nervous system (CNS); alterations of its homeostasis have deleterious consequences on neuronal functions. The levels of several sterols, upstream of cholesterol, are markedly decreased within the striatum of HD mouse model. Transcription of cholesterol biosynthetic genes is reduced in HD cell and mouse models as well as post-mortem striatal and cortical tissues from HD patients. Since the dynamic of brain cholesterol metabolism is complex, it is essential to establish the best method to target it in HD. Cholesterol, which does not cross the blood-brain-barrier, is locally synthesized and renewed within the brain. All cell types in the CNS synthesize cholesterol during development but as they progress through adulthood, neurons down-regulate their cholesterol synthesis and turn to astrocytes for their full supply. Cellular levels of cholesterol reflect the dynamic balance between synthesis, uptake and export, all integrated into the context of the cross talk between neurons and glial cells. In this review, we describe the latest advances regarding the role of cholesterol deregulation in neuronal functions and how this could be a determinant factor in neuronal degeneration and HD progression. The pathways and major mechanisms by which cholesterol and sterols are regulated in the CNS will be described. From this overview, we discuss the main clinical strategies for manipulating cholesterol metabolism in the CNS, and how to reinstate a proper balance in HD.
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Affiliation(s)
- Radhia Kacher
- Institut du Cerveau - Paris Brain Institute (ICM), AP-HP, INSERM, CNRS, University Hospital Pitié-Salpêtrière, Sorbonne Université, Paris, France
- INSERM, U1216, Grenoble Institut Neurosciences, Université Grenoble Alpes, Grenoble, France
| | - Coline Mounier
- Neuroscience Paris Seine, Institut de Biologie Paris-Seine, Faculté des Sciences et Ingénierie, Sorbonne Université, Paris, France
- Centre National de la Recherche Scientifique, UMR 8246, Paris, France
- U1130, Institut National de la Santé et de la Recherche Médicale, Paris, France
| | - Jocelyne Caboche
- Neuroscience Paris Seine, Institut de Biologie Paris-Seine, Faculté des Sciences et Ingénierie, Sorbonne Université, Paris, France
- Centre National de la Recherche Scientifique, UMR 8246, Paris, France
- U1130, Institut National de la Santé et de la Recherche Médicale, Paris, France
| | - Sandrine Betuing
- Neuroscience Paris Seine, Institut de Biologie Paris-Seine, Faculté des Sciences et Ingénierie, Sorbonne Université, Paris, France
- Centre National de la Recherche Scientifique, UMR 8246, Paris, France
- U1130, Institut National de la Santé et de la Recherche Médicale, Paris, France
- *Correspondence: Sandrine Betuing,
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33
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Serrano ME, Kim E, Petrinovic MM, Turkheimer F, Cash D. Imaging Synaptic Density: The Next Holy Grail of Neuroscience? Front Neurosci 2022; 16:796129. [PMID: 35401097 PMCID: PMC8990757 DOI: 10.3389/fnins.2022.796129] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Accepted: 02/15/2022] [Indexed: 12/19/2022] Open
Abstract
The brain is the central and most complex organ in the nervous system, comprising billions of neurons that constantly communicate through trillions of connections called synapses. Despite being formed mainly during prenatal and early postnatal development, synapses are continually refined and eliminated throughout life via complicated and hitherto incompletely understood mechanisms. Failure to correctly regulate the numbers and distribution of synapses has been associated with many neurological and psychiatric disorders, including autism, epilepsy, Alzheimer’s disease, and schizophrenia. Therefore, measurements of brain synaptic density, as well as early detection of synaptic dysfunction, are essential for understanding normal and abnormal brain development. To date, multiple synaptic density markers have been proposed and investigated in experimental models of brain disorders. The majority of the gold standard methodologies (e.g., electron microscopy or immunohistochemistry) visualize synapses or measure changes in pre- and postsynaptic proteins ex vivo. However, the invasive nature of these classic methodologies precludes their use in living organisms. The recent development of positron emission tomography (PET) tracers [such as (18F)UCB-H or (11C)UCB-J] that bind to a putative synaptic density marker, the synaptic vesicle 2A (SV2A) protein, is heralding a likely paradigm shift in detecting synaptic alterations in patients. Despite their limited specificity, novel, non-invasive magnetic resonance (MR)-based methods also show promise in inferring synaptic information by linking to glutamate neurotransmission. Although promising, all these methods entail various advantages and limitations that must be addressed before becoming part of routine clinical practice. In this review, we summarize and discuss current ex vivo and in vivo methods of quantifying synaptic density, including an evaluation of their reliability and experimental utility. We conclude with a critical assessment of challenges that need to be overcome before successfully employing synaptic density biomarkers as diagnostic and/or prognostic tools in the study of neurological and neuropsychiatric disorders.
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Affiliation(s)
- Maria Elisa Serrano
- Department of Neuroimaging, The BRAIN Centre, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom.,Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, Kings College London, London, United Kingdom
| | - Eugene Kim
- Department of Neuroimaging, The BRAIN Centre, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom.,Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, Kings College London, London, United Kingdom
| | - Marija M Petrinovic
- Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom.,MRC Centre for Neurodevelopmental Disorders, King's College London, London, United Kingdom
| | - Federico Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, Kings College London, London, United Kingdom
| | - Diana Cash
- Department of Neuroimaging, The BRAIN Centre, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom.,Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, Kings College London, London, United Kingdom
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34
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Kurematsu C, Sawada M, Ohmuraya M, Tanaka M, Kuboyama K, Ogino T, Matsumoto M, Oishi H, Inada H, Ishido Y, Sakakibara Y, Nguyen HB, Thai TQ, Kohsaka S, Ohno N, Yamada MK, Asai M, Sokabe M, Nabekura J, Asano K, Tanaka M, Sawamoto K. Synaptic pruning of murine adult-born neurons by microglia depends on phosphatidylserine. J Exp Med 2022; 219:213073. [PMID: 35297954 PMCID: PMC9195048 DOI: 10.1084/jem.20202304] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Revised: 08/13/2021] [Accepted: 11/30/2021] [Indexed: 12/21/2022] Open
Abstract
New neurons, continuously added in the adult olfactory bulb (OB) and hippocampus, are involved in information processing in neural circuits. Here, we show that synaptic pruning of adult-born neurons by microglia depends on phosphatidylserine (PS), whose exposure on dendritic spines is inversely correlated with their input activity. To study the role of PS in spine pruning by microglia in vivo, we developed an inducible transgenic mouse line, in which the exposed PS is masked by a dominant-negative form of milk fat globule-EGF-factor 8 (MFG-E8), MFG-E8D89E. In this transgenic mouse, the spine pruning of adult-born neurons by microglia is impaired in the OB and hippocampus. Furthermore, the electrophysiological properties of these adult-born neurons are altered in MFG-E8D89E mice. These data suggest that PS is involved in the microglial spine pruning and the functional maturation of adult-born neurons. The MFG-E8D89E-based genetic approach shown in this study has broad applications for understanding the biology of PS-mediated phagocytosis in vivo.
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Affiliation(s)
- Chihiro Kurematsu
- Department of Developmental and Regenerative Neurobiology, Institute of Brain Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Masato Sawada
- Department of Developmental and Regenerative Neurobiology, Institute of Brain Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.,Division of Neural Development and Regeneration, National Institute for Physiological Sciences, Okazaki, Japan
| | - Masaki Ohmuraya
- Department of Genetics, Hyogo College of Medicine, Nishinomiya, Japan
| | - Motoki Tanaka
- Department of Disease Model, Institute for Developmental Research, Aichi Developmental Disability Center, Kasugai, Japan
| | - Kazuya Kuboyama
- Department of Developmental and Regenerative Neurobiology, Institute of Brain Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Takashi Ogino
- Department of Developmental and Regenerative Neurobiology, Institute of Brain Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Mami Matsumoto
- Department of Developmental and Regenerative Neurobiology, Institute of Brain Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.,Section of Electron Microscopy, Supportive Center for Brain Research, National Institute for Physiological Sciences, Okazaki, Japan
| | - Hisashi Oishi
- Department of Comparative and Experimental Medicine, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Hiroyuki Inada
- Division of Homeostatic Development, National Institute for Physiological Sciences, Okazaki, Japan
| | - Yuri Ishido
- Department of Developmental and Regenerative Neurobiology, Institute of Brain Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Yukina Sakakibara
- Department of Developmental and Regenerative Neurobiology, Institute of Brain Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Huy Bang Nguyen
- Section of Electron Microscopy, Supportive Center for Brain Research, National Institute for Physiological Sciences, Okazaki, Japan.,Department of Anatomy, Faculty of Medicine, University of Medicine and Pharmacy at Ho Chi Minh City, Ho Chi Minh City, Vietnam
| | - Truc Quynh Thai
- Section of Electron Microscopy, Supportive Center for Brain Research, National Institute for Physiological Sciences, Okazaki, Japan.,Department of Histology-Embryology-Genetics, Faculty of Basic Medical Sciences, Pham Ngoc Thach University of Medicine, Ho Chi Minh City, Vietnam
| | - Shinichi Kohsaka
- National Institute of Neuroscience, National Center of Neurology and Psychiatry, Kodaira, Japan
| | - Nobuhiko Ohno
- Department of Anatomy, Division of Histology and Cell Biology, Jichi Medical University, School of Medicine, Shimotsuke, Japan.,Division of Ultrastructural Research, National Institute for Physiological Sciences, Okazaki, Japan
| | - Maki K Yamada
- Department of Neuropharmacology, Kagawa School of Pharmaceutical Sciences and Institute of Neuroscience, Tokushima Bunri University, Sanuki, Japan
| | - Masato Asai
- Department of Disease Model, Institute for Developmental Research, Aichi Developmental Disability Center, Kasugai, Japan
| | - Masahiro Sokabe
- Mechanobiology Laboratory, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Junichi Nabekura
- Division of Homeostatic Development, National Institute for Physiological Sciences, Okazaki, Japan
| | - Kenichi Asano
- Laboratory of Immune Regulation, Tokyo University of Pharmacy and Life Sciences, Hachioji, Japan
| | - Masato Tanaka
- Laboratory of Immune Regulation, Tokyo University of Pharmacy and Life Sciences, Hachioji, Japan
| | - Kazunobu Sawamoto
- Department of Developmental and Regenerative Neurobiology, Institute of Brain Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.,Division of Neural Development and Regeneration, National Institute for Physiological Sciences, Okazaki, Japan
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35
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Han J, Chitu V, Stanley ER, Wszolek ZK, Karrenbauer VD, Harris RA. Inhibition of colony stimulating factor-1 receptor (CSF-1R) as a potential therapeutic strategy for neurodegenerative diseases: opportunities and challenges. Cell Mol Life Sci 2022; 79:219. [PMID: 35366105 PMCID: PMC8976111 DOI: 10.1007/s00018-022-04225-1] [Citation(s) in RCA: 39] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 02/06/2022] [Accepted: 02/26/2022] [Indexed: 12/12/2022]
Abstract
Microglia are specialized dynamic immune cells in the central nervous system (CNS) that plays a crucial role in brain homeostasis and in disease states. Persistent neuroinflammation is considered a hallmark of many neurodegenerative diseases, including Alzheimer’s disease (AD), Parkinson's disease (PD), Huntington’s disease (HD), amyotrophic lateral sclerosis (ALS) and primary progressive multiple sclerosis (MS). Colony stimulating factor 1-receptor (CSF-1R) is predominantly expressed on microglia and its expression is significantly increased in neurodegenerative diseases. Cumulative findings have indicated that CSF-1R inhibitors can have beneficial effects in preclinical neurodegenerative disease models. Research using CSF-1R inhibitors has now been extended into non-human primates and humans. This review article summarizes the most recent advances using CSF-1R inhibitors in different neurodegenerative conditions including AD, PD, HD, ALS and MS. Potential challenges for translating these findings into clinical practice are presented.
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Affiliation(s)
- Jinming Han
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Violeta Chitu
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY 10461 USA
| | - E. Richard Stanley
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY 10461 USA
| | | | - Virginija Danylaité Karrenbauer
- Department of Clinical Neuroscience, Center for Molecular Medicine L8:04, Karolinska Institutet, Karolinska University Hospital, 171 76 Stockholm, Sweden
- Department of Neurology, Karolinska University Hospital, Stockholm, Sweden
| | - Robert A. Harris
- Applied Immunology and Immunotherapy, Department of Clinical Neuroscience, Center for Molecular Medicine, Karolinska Institutet, Karolinska University Hospital, Solna, Sweden
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Taheri F, Taghizadeh E, Navashenaq JG, Rezaee M, Gheibihayat SM. The role of efferocytosis in neuro-degenerative diseases. Neurol Sci 2022; 43:1593-1603. [PMID: 35059903 DOI: 10.1007/s10072-021-05835-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2021] [Accepted: 12/11/2021] [Indexed: 02/06/2023]
Abstract
Efferocytosis has a critical role in maintaining tissues and organs' homeostasis by removing apoptotic cells. It is essential for human health, and disturbances in efferocytosis may result indifferent illnesses. In case of inadequate clearance of the dead cells, the content in the cells would be released. In fact, it induces some damages to the tissue and leads to the prolonged inflammation, so unsuitable phagocytosis of the apoptotic cells is involved in occurrence as well as expansion of numerous human chronic inflammatory diseases. Studies have shown age dependence of the neuro-degenerative diseases, which are largely due to the neuro-inflammation and the loss of neurons and thus cause the brain's functional disorders. Efferocytosis is coupled to anti-inflammatory responses that contribute to the elimination of the dying neurons in neuro-degenerative diseases, so its disruption may make a risk factor in numerous human chronic inflammatory diseases such as multiple sclerosis, Alzheimer's disease, glioblastoma, and Rett syndrome. This study is a review of the efferocytosis molecular pathways and their role in neuro-degenerative diseases in order to discover a new treatment option to cure patients.
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Affiliation(s)
- Forough Taheri
- Shahrekord Branch, Islamic Azad University, Shahrekord, Iran
| | - Eskandar Taghizadeh
- Department of Medical Genetic, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | | | - Mehdi Rezaee
- Department of Medical Biotechnology, School of Advanced Technologies, Shahrekord University of Medical Sciences, Shahrekord, Iran.,Cellular and Molecular Research Center, Basic Health Sciences Institute, Shahrekord University of Medical Sciences, Shahrekord, Iran
| | - Seyed Mohammad Gheibihayat
- Department of Medical Biotechnology, School of Medicine, Shahid Sadoughi University of Medical Sciences, P.O. Box: 8915173143, Yazd, Iran.
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Decoeur F, Picard K, St-Pierre MK, Greenhalgh AD, Delpech JC, Sere A, Layé S, Tremblay ME, Nadjar A. N-3 PUFA Deficiency Affects the Ultrastructural Organization and Density of White Matter Microglia in the Developing Brain of Male Mice. Front Cell Neurosci 2022; 16:802411. [PMID: 35221920 PMCID: PMC8866569 DOI: 10.3389/fncel.2022.802411] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 01/17/2022] [Indexed: 02/03/2023] Open
Abstract
Over the last century, westernization of dietary habits has led to a dramatic reduction in dietary intake of n-3 polyunsaturated fatty acids (n-3 PUFAs). In particular, low maternal intake of n-3 PUFAs throughout gestation and lactation causes defects in brain myelination. Microglia are recognized for their critical contribution to neurodevelopmental processes, such as myelination. These cells invade the white matter in the first weeks of the post-natal period, where they participate in oligodendrocyte maturation and myelin production. Therefore, we investigated whether an alteration of white matter microglia accompanies the myelination deficits observed in the brain of n-3 PUFA-deficient animals. Macroscopic imaging analysis shows that maternal n-3 PUFA deficiency decreases the density of white matter microglia around post-natal day 10. Microscopic electron microscopy analyses also revealed alterations of microglial ultrastructure, a decrease in the number of contacts between microglia and myelin sheet, and a decreased amount of myelin debris in their cell body. White matter microglia further displayed increased mitochondrial abundance and network area under perinatal n-3 PUFA deficiency. Overall, our data suggest that maternal n-3 PUFA deficiency alters the structure and function of microglial cells located in the white matter of pups early in life, and this could be the key to understand myelination deficits during neurodevelopment.
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Affiliation(s)
- Fanny Decoeur
- INRAE, Bordeaux INP, NutriNeuro, Université de Bordeaux, Bordeaux, France
| | - Katherine Picard
- Axe Neurosciences, Centre de Recherche du CHU de Québec–Université Laval, Québec, QC, Canada
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
- Département de Médecine Moléculaire, Université Laval, Québec, QC, Canada
| | - Marie-Kim St-Pierre
- Axe Neurosciences, Centre de Recherche du CHU de Québec–Université Laval, Québec, QC, Canada
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
- Département de Médecine Moléculaire, Université Laval, Québec, QC, Canada
| | | | | | - Alexandra Sere
- INRAE, Bordeaux INP, NutriNeuro, Université de Bordeaux, Bordeaux, France
| | - Sophie Layé
- INRAE, Bordeaux INP, NutriNeuro, Université de Bordeaux, Bordeaux, France
| | - Marie-Eve Tremblay
- Axe Neurosciences, Centre de Recherche du CHU de Québec–Université Laval, Québec, QC, Canada
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
- Département de Médecine Moléculaire, Université Laval, Québec, QC, Canada
- Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada
- Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, BC, Canada
| | - Agnès Nadjar
- INRAE, Bordeaux INP, NutriNeuro, Université de Bordeaux, Bordeaux, France
- Neurocentre Magendie, U1215, INSERM-Université de Bordeaux, Bordeaux, France
- Institut Universitaire de France (IUF), Paris, France
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Allison RL, Welby E, Khayrullina G, Burnett BG, Ebert AD. Viral mediated knockdown of GATA6 in SMA iPSC-derived astrocytes prevents motor neuron loss and microglial activation. Glia 2022; 70:989-1004. [PMID: 35088910 PMCID: PMC9303278 DOI: 10.1002/glia.24153] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2021] [Revised: 01/18/2022] [Accepted: 01/18/2022] [Indexed: 12/22/2022]
Abstract
Spinal muscular atrophy (SMA), a pediatric genetic disorder, is characterized by the profound loss of spinal cord motor neurons and subsequent muscle atrophy and death. Although the mechanisms underlying motor neuron loss are not entirely clear, data from our work and others support the idea that glial cells contribute to disease pathology. GATA6, a transcription factor that we have previously shown to be upregulated in SMA astrocytes, is negatively regulated by SMN (survival motor neuron) and can increase the expression of inflammatory regulator NFκB. In this study, we identified upregulated GATA6 as a contributor to increased activation, pro-inflammatory ligand production, and neurotoxicity in spinal-cord patterned astrocytes differentiated from SMA patient induced pluripotent stem cells. Reducing GATA6 expression in SMA astrocytes via lentiviral infection ameliorated these effects to healthy control levels. Additionally, we found that SMA astrocytes contribute to SMA microglial phagocytosis, which was again decreased by lentiviral-mediated knockdown of GATA6. Together these data identify a role of GATA6 in SMA astrocyte pathology and further highlight glia as important targets of therapeutic intervention in SMA.
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Affiliation(s)
- Reilly L Allison
- Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Emily Welby
- Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Guzal Khayrullina
- Department of Anatomy, Physiology, and Genetics, Uniformed Services University, Bethesda, Maryland, USA
| | - Barrington G Burnett
- Department of Anatomy, Physiology, and Genetics, Uniformed Services University, Bethesda, Maryland, USA
| | - Allison D Ebert
- Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
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Floreani L, Ansaloni F, Mangoni D, Agostoni E, Sanges R, Persichetti F, Gustincich S. Analysis of LINE1 Retrotransposons in Huntington’s Disease. Front Cell Neurosci 2022; 15:743797. [PMID: 35095420 PMCID: PMC8795916 DOI: 10.3389/fncel.2021.743797] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Accepted: 12/27/2021] [Indexed: 12/27/2022] Open
Abstract
Transposable elements (TEs) are mobile genetic elements that made up about half the human genome. Among them, the autonomous non-LTR retrotransposon long interspersed nuclear element-1 (L1) is the only currently active TE in mammals and covers about 17% of the mammalian genome. L1s exert their function as structural elements in the genome, as transcribed RNAs to influence chromatin structure and as retrotransposed elements to shape genomic variation in somatic cells. L1s activity has been shown altered in several diseases of the nervous system. Huntington disease (HD) is a dominantly inherited neurodegenerative disorder caused by an expansion of a CAG repeat in the HTT gene which leads to a gradual loss of neurons most prominently in the striatum and, to a lesser extent, in cortical brain regions. The length of the expanded CAG tract is related to age at disease onset, with longer repeats leading to earlier onset. Here we carried out bioinformatic analysis of public RNA-seq data of a panel of HD mouse models showing that a decrease of L1 RNA expression recapitulates two hallmarks of the disease: it correlates to CAG repeat length and it occurs in the striatum, the site of neurodegeneration. Results were then experimentally validated in HttQ111 knock-in mice. The expression of L1-encoded proteins was independent from L1 RNA levels and differentially regulated in time and tissues. The pattern of expression L1 RNAs in human HD post-mortem brains showed similarity to mouse models of the disease. This work suggests the need for further study of L1s in HD and adds support to the current hypothesis that dysregulation of TEs may be involved in neurodegenerative diseases.
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Affiliation(s)
- Lavinia Floreani
- Area of Neuroscience, Scuola Internazionale Superiore di Studi Avanzati (SISSA), Trieste, Italy
| | - Federico Ansaloni
- Area of Neuroscience, Scuola Internazionale Superiore di Studi Avanzati (SISSA), Trieste, Italy
- Central RNA Laboratory, Istituto Italiano di Tecnologia—IIT, Genova, Italy
| | - Damiano Mangoni
- Central RNA Laboratory, Istituto Italiano di Tecnologia—IIT, Genova, Italy
| | - Elena Agostoni
- Area of Neuroscience, Scuola Internazionale Superiore di Studi Avanzati (SISSA), Trieste, Italy
| | - Remo Sanges
- Area of Neuroscience, Scuola Internazionale Superiore di Studi Avanzati (SISSA), Trieste, Italy
- Central RNA Laboratory, Istituto Italiano di Tecnologia—IIT, Genova, Italy
- *Correspondence: Remo Sanges,
| | - Francesca Persichetti
- Department of Health Sciences, University of Piemonte Orientale “ A. Avogadro,”Novara, Italy
- Francesca Persichetti,
| | - Stefano Gustincich
- Area of Neuroscience, Scuola Internazionale Superiore di Studi Avanzati (SISSA), Trieste, Italy
- Central RNA Laboratory, Istituto Italiano di Tecnologia—IIT, Genova, Italy
- Stefano Gustincich,
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Maternal high-fat diet in mice induces cerebrovascular, microglial and long-term behavioural alterations in offspring. Commun Biol 2022; 5:26. [PMID: 35017640 PMCID: PMC8752761 DOI: 10.1038/s42003-021-02947-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Various environmental exposures during pregnancy, like maternal diet, can compromise, at critical periods of development, the neurovascular maturation of the offspring. Foetal exposure to maternal high-fat diet (mHFD), common to Western societies, has been shown to disturb neurovascular development in neonates and long-term permeability of the neurovasculature. Nevertheless, the effects of mHFD on the offspring’s cerebrovascular health remains largely elusive. Here, we sought to address this knowledge gap by using a translational mouse model of mHFD exposure. Three-dimensional and ultrastructure analysis of the neurovascular unit (vasculature and parenchymal cells) in mHFD-exposed offspring revealed major alterations of the neurovascular organization and metabolism. These alterations were accompanied by changes in the expression of genes involved in metabolism and immunity, indicating that neurovascular changes may result from abnormal brain metabolism and immune regulation. In addition, mHFD-exposed offspring showed persisting behavioural alterations reminiscent of neurodevelopmental disorders, specifically an increase in stereotyped and repetitive behaviours into adulthood. In order to advance our understanding of the effects of maternal high-fat diet (mHFD) on the cerebrovascular health of offspring, Bordeleau et al. use a translational mouse model of mHFD exposure. They demonstrate that mHFD induces cerebrovascular and microglial changes in the offspring as well as behavioural alterations that are reminiscent of neurodevelopmental disorders associated with repetitive behaviours at adulthood.
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Marcoli M, Agnati LF, Franco R, Cortelli P, Anderlini D, Guidolin D, Cervetto C, Maura G. Modulating brain integrative actions as a new perspective on pharmacological approaches to neuropsychiatric diseases. Front Endocrinol (Lausanne) 2022; 13:1038874. [PMID: 36699033 PMCID: PMC9868467 DOI: 10.3389/fendo.2022.1038874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 12/20/2022] [Indexed: 01/11/2023] Open
Abstract
A critical aspect of drug development in the therapy of neuropsychiatric diseases is the "Target Problem", that is, the selection of a proper target after not simply the etiopathological classification but rather the detection of the supposed structural and/or functional alterations in the brain networks. There are novel ways of approaching the development of drugs capable of overcoming or at least reducing the deficits without triggering deleterious side effects. For this purpose, a model of brain network organization is needed, and the main aspects of its integrative actions must also be established. Thus, to this aim we here propose an updated model of the brain as a hyper-network in which i) the penta-partite synapses are suggested as key nodes of the brain hyper-network and ii) interacting cell surface receptors appear as both decoders of signals arriving to the network and targets of central nervous system diseases. The integrative actions of the brain networks follow the "Russian Doll organization" including the micro (i.e., synaptic) and nano (i.e., molecular) levels. In this scenario, integrative actions result primarily from protein-protein interactions. Importantly, the macromolecular complexes arising from these interactions often have novel structural binding sites of allosteric nature. Taking G protein-coupled receptors (GPCRs) as potential targets, GPCRs heteromers offer a way to increase the selectivity of pharmacological treatments if proper allosteric drugs are designed. This assumption is founded on the possible selectivity of allosteric interventions on G protein-coupled receptors especially when organized as "Receptor Mosaics" at penta-partite synapse level.
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Affiliation(s)
- Manuela Marcoli
- Department of Pharmacy, Section of Pharmacology and Toxicology, University of Genova, Genova, Italy
- Interuniversity Center for the Promotion of the 3Rs Principles in Teaching and Research (Centro 3R), Pisa, Italy
- Center of Excellence for Biomedical Research, University of Genova, Genova, Italy
- *Correspondence: Manuela Marcoli, ; Luigi F. Agnati,
| | - Luigi F. Agnati
- Department of Biomedical, Metabolic Sciences and Neuroscience, University of Modena and Reggio Emilia, Modena, Italy
- *Correspondence: Manuela Marcoli, ; Luigi F. Agnati,
| | - Rafael Franco
- CiberNed Network Center for Neurodegenerative diseases, National Spanish Health Institute Carlos III, Madrid, Spain
- Molecular Neurobiology laboratory, Department of Biochemistry and Molecular Biomedicine. Universitat de Barcelona, Barcelona, Spain
- School of Chemistry, Universitat de Barcelona, Barcelona, Spain
| | - Pietro Cortelli
- Department of Biomedical and NeuroMotor Sciences (DIBINEM), Alma Mater Studiorum, University of Bologna, Bologna, Italy
- Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy
| | - Deanna Anderlini
- Centre for Sensorimotor Performance, The University of Queensland, Brisbane, QLD, Australia
| | - Diego Guidolin
- Department of Neuroscience, University of Padova, Padova, Italy
| | - Chiara Cervetto
- Department of Pharmacy, Section of Pharmacology and Toxicology, University of Genova, Genova, Italy
- Interuniversity Center for the Promotion of the 3Rs Principles in Teaching and Research (Centro 3R), Pisa, Italy
| | - Guido Maura
- Department of Pharmacy, Section of Pharmacology and Toxicology, University of Genova, Genova, Italy
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Aramideh JA, Vidal-Itriago A, Morsch M, Graeber MB. Cytokine Signalling at the Microglial Penta-Partite Synapse. Int J Mol Sci 2021; 22:ijms222413186. [PMID: 34947983 PMCID: PMC8708012 DOI: 10.3390/ijms222413186] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Revised: 12/01/2021] [Accepted: 12/02/2021] [Indexed: 12/28/2022] Open
Abstract
Microglial cell processes form part of a subset of synaptic contacts that have been dubbed microglial tetra-partite or quad-partite synapses. Since tetrapartite may also refer to the presence of extracellular matrix components, we propose the more precise term microglial penta-partite synapse for synapses that show a microglial cell process in close physical proximity to neuronal and astrocytic synaptic constituents. Microglial cells are now recognised as key players in central nervous system (CNS) synaptic changes. When synaptic plasticity involving microglial penta-partite synapses occurs, microglia may utilise their cytokine arsenal to facilitate the generation of new synapses, eliminate those that are not needed anymore, or modify the molecular and structural properties of the remaining synaptic contacts. In addition, microglia–synapse contacts may develop de novo under pathological conditions. Microglial penta-partite synapses have received comparatively little attention as unique sites in the CNS where microglial cells, cytokines and other factors they release have a direct influence on the connections between neurons and their function. It concerns our understanding of the penta-partite synapse where the confusion created by the term “neuroinflammation” is most counterproductive. The mere presence of activated microglia or the release of their cytokines may occur independent of inflammation, and penta-partite synapses are not usually active in a neuroimmunological sense. Clarification of these details is the main purpose of this review, specifically highlighting the relationship between microglia, synapses, and the cytokines that can be released by microglial cells in health and disease.
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Affiliation(s)
- Jason Abbas Aramideh
- Brain and Mind Centre, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW 2006, Australia;
| | - Andres Vidal-Itriago
- Faculty of Medicine, Health & Human Sciences, Macquarie Medical School, Macquarie University, Sydney, NSW 2109, Australia; (A.V.-I.); (M.M.)
| | - Marco Morsch
- Faculty of Medicine, Health & Human Sciences, Macquarie Medical School, Macquarie University, Sydney, NSW 2109, Australia; (A.V.-I.); (M.M.)
| | - Manuel B. Graeber
- Brain and Mind Centre, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW 2006, Australia;
- Correspondence:
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Kim C, Yousefian-Jazi A, Choi SH, Chang I, Lee J, Ryu H. Non-Cell Autonomous and Epigenetic Mechanisms of Huntington's Disease. Int J Mol Sci 2021; 22:12499. [PMID: 34830381 PMCID: PMC8617801 DOI: 10.3390/ijms222212499] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 11/10/2021] [Accepted: 11/15/2021] [Indexed: 02/06/2023] Open
Abstract
Huntington's disease (HD) is a rare neurodegenerative disorder caused by an expansion of CAG trinucleotide repeat located in the exon 1 of Huntingtin (HTT) gene in human chromosome 4. The HTT protein is ubiquitously expressed in the brain. Specifically, mutant HTT (mHTT) protein-mediated toxicity leads to a dramatic degeneration of the striatum among many regions of the brain. HD symptoms exhibit a major involuntary movement followed by cognitive and psychiatric dysfunctions. In this review, we address the conventional role of wild type HTT (wtHTT) and how mHTT protein disrupts the function of medium spiny neurons (MSNs). We also discuss how mHTT modulates epigenetic modifications and transcriptional pathways in MSNs. In addition, we define how non-cell autonomous pathways lead to damage and death of MSNs under HD pathological conditions. Lastly, we overview therapeutic approaches for HD. Together, understanding of precise neuropathological mechanisms of HD may improve therapeutic approaches to treat the onset and progression of HD.
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Affiliation(s)
- Chaebin Kim
- Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, Korea; (C.K.); (A.Y.-J.); (S.-H.C.)
| | - Ali Yousefian-Jazi
- Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, Korea; (C.K.); (A.Y.-J.); (S.-H.C.)
| | - Seung-Hye Choi
- Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, Korea; (C.K.); (A.Y.-J.); (S.-H.C.)
| | - Inyoung Chang
- Department of Biology, Boston University, Boston, MA 02215, USA;
| | - Junghee Lee
- Boston University Alzheimer’s Disease Research Center, Boston University, Boston, MA 02118, USA
- Department of Neurology, Boston University School of Medicine, Boston, MA 02118, USA
- VA Boston Healthcare System, Boston, MA 02130, USA
| | - Hoon Ryu
- Brain Science Institute, Korea Institute of Science and Technology, Seoul 02792, Korea; (C.K.); (A.Y.-J.); (S.-H.C.)
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Krukowski K, Nolan A, Becker M, Picard K, Vernoux N, Frias ES, Feng X, Tremblay ME, Rosi S. Novel microglia-mediated mechanisms underlying synaptic loss and cognitive impairment after traumatic brain injury. Brain Behav Immun 2021; 98:122-135. [PMID: 34403733 PMCID: PMC9119574 DOI: 10.1016/j.bbi.2021.08.210] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 08/03/2021] [Accepted: 08/06/2021] [Indexed: 12/30/2022] Open
Abstract
Traumatic brain injury (TBI) is one of the leading causes of long-term neurological disability in the world. Currently, there are no therapeutics for treating the deleterious consequences of brain trauma; this is in part due to a lack of complete understanding of cellular processes that underlie TBI-related pathologies. Following TBI, microglia, the brain resident immune cells, turn into a "reactive" state characterized by the production of inflammatory mediators that contribute to the development of cognitive deficits. Utilizing multimodal, state-of-the-art techniques that widely span from ultrastructural analysis to optogenetic interrogation of circuit function, we investigated the reactive microglia phenotype one week after injury when learning and memory deficits are also measured. Microglia displayed increased: (i) phagocytic activity in vivo, (ii) synaptic engulfment, (iii) increased neuronal contact, including with dendrites and somata (termed 'satellite microglia'). Functionally, satellite microglia might impact somatic inhibition as demonstrated by the associated reduction in inhibitory synaptic drive. Cumulatively, here we demonstrate novel microglia-mediated mechanisms that may contribute to synaptic loss and cognitive impairment after traumatic brain injury.
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Affiliation(s)
- Karen Krukowski
- Department of Physical Therapy and Rehabilitation Science, University of California, San Francisco, CA, USA, Brain and Spinal Injury Center, University of California, San Francisco, CA, USA
| | - Amber Nolan
- Department of Physical Therapy and Rehabilitation Science, University of California, San Francisco, CA, USA, Brain and Spinal Injury Center, University of California, San Francisco, CA, USA
| | - McKenna Becker
- Department of Physical Therapy and Rehabilitation Science, University of California, San Francisco, CA, USA, Brain and Spinal Injury Center, University of California, San Francisco, CA, USA
| | - Katherine Picard
- Axe Neurosciences, CRCHU de Québec-Université Laval, Québec, QC, Canada
| | - Nathalie Vernoux
- Axe Neurosciences, CRCHU de Québec-Université Laval, Québec, QC, Canada
| | - Elma S. Frias
- Department of Physical Therapy and Rehabilitation Science, University of California, San Francisco, CA, USA, Brain and Spinal Injury Center, University of California, San Francisco, CA, USA, Department of Biomedical Sciences, University of California, San Francisco, CA, USA
| | - Xi Feng
- Department of Physical Therapy and Rehabilitation Science, University of California, San Francisco, CA, USA, Brain and Spinal Injury Center, University of California, San Francisco, CA, USA
| | - Marie-Eve Tremblay
- Axe Neurosciences, CRCHU de Québec-Université Laval, Québec, QC, Canada; Molecular Medicine Department, Université Laval, Québec, QC, Canada; Division of Medical Sciences, University of Victoria, Victoria, BC, Canada; Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, BC, Canada.
| | - Susanna Rosi
- Department of Physical Therapy and Rehabilitation Science, University of California, San Francisco, CA, USA; Brain and Spinal Injury Center, University of California, San Francisco, CA, USA; Department of Biomedical Sciences, University of California, San Francisco, CA, USA; Department of Neurological Surgery, University of California, San Francisco, CA, USA; Weill Institute for Neuroscience, University of California San Francisco, CA, USA; Kavli Institute of Fundamental Neuroscience, University of California San Francisco, CA, USA.
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Lee JW, Chun W, Lee HJ, Kim SM, Min JH, Kim DY, Kim MO, Ryu HW, Lee SU. The Role of Microglia in the Development of Neurodegenerative Diseases. Biomedicines 2021; 9:biomedicines9101449. [PMID: 34680566 PMCID: PMC8533549 DOI: 10.3390/biomedicines9101449] [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: 09/10/2021] [Revised: 10/04/2021] [Accepted: 10/08/2021] [Indexed: 01/15/2023] Open
Abstract
Microglia play an important role in the maintenance and neuroprotection of the central nervous system (CNS) by removing pathogens, damaged neurons, and plaques. Recent observations emphasize that the promotion and development of neurodegenerative diseases (NDs) are closely related to microglial activation. In this review, we summarize the contribution of microglial activation and its associated mechanisms in NDs, such as epilepsy, Alzheimer's disease (AD), Parkinson's disease (PD), and Huntington's disease (HD), based on recent observations. This review also briefly introduces experimental animal models of epilepsy, AD, PD, and HD. Thus, this review provides a better understanding of microglial functions in the development of NDs, suggesting that microglial targeting could be an effective therapeutic strategy for these diseases.
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Affiliation(s)
- Jae-Won Lee
- Natural Medicine Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Cheongju 28116, Korea; (S.-M.K.); (J.-H.M.); (D.-Y.K.)
- Correspondence: (J.-W.L.); (M.-O.K.); (H.W.R.); (S.U.L.); Tel.: +82-43-240-6135 (J.-W.L.)
| | - Wanjoo Chun
- Department of Pharmacology, College of Medicine, Kangwon National University, Chuncheon 24341, Korea; (W.C.); (H.J.L.)
| | - Hee Jae Lee
- Department of Pharmacology, College of Medicine, Kangwon National University, Chuncheon 24341, Korea; (W.C.); (H.J.L.)
| | - Seong-Man Kim
- Natural Medicine Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Cheongju 28116, Korea; (S.-M.K.); (J.-H.M.); (D.-Y.K.)
| | - Jae-Hong Min
- Natural Medicine Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Cheongju 28116, Korea; (S.-M.K.); (J.-H.M.); (D.-Y.K.)
| | - Doo-Young Kim
- Natural Medicine Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Cheongju 28116, Korea; (S.-M.K.); (J.-H.M.); (D.-Y.K.)
| | - Mun-Ock Kim
- Natural Medicine Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Cheongju 28116, Korea; (S.-M.K.); (J.-H.M.); (D.-Y.K.)
- Correspondence: (J.-W.L.); (M.-O.K.); (H.W.R.); (S.U.L.); Tel.: +82-43-240-6135 (J.-W.L.)
| | - Hyung Won Ryu
- Natural Medicine Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Cheongju 28116, Korea; (S.-M.K.); (J.-H.M.); (D.-Y.K.)
- Correspondence: (J.-W.L.); (M.-O.K.); (H.W.R.); (S.U.L.); Tel.: +82-43-240-6135 (J.-W.L.)
| | - Su Ui Lee
- Natural Medicine Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Cheongju 28116, Korea; (S.-M.K.); (J.-H.M.); (D.-Y.K.)
- Correspondence: (J.-W.L.); (M.-O.K.); (H.W.R.); (S.U.L.); Tel.: +82-43-240-6135 (J.-W.L.)
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46
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Tremblay MÈ. Microglial functional alteration and increased diversity in the challenged brain: Insights into novel targets for intervention. Brain Behav Immun Health 2021; 16:100301. [PMID: 34589793 PMCID: PMC8474548 DOI: 10.1016/j.bbih.2021.100301] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 07/12/2021] [Accepted: 07/13/2021] [Indexed: 02/07/2023] Open
Abstract
Microglia are the resident immune cells of the central nervous system (CNS) parenchyma, which perform beneficial physiological roles across life. These immune cells actively maintain CNS health by clearing toxic debris and removing dysfunctional or degenerating cells. They also modify the wiring of neuronal circuits, by acting on the formation, modification, and elimination of synapses-the connections between neurons. Microglia furthermore recently emerged as highly diverse cells comprising several structural and functional states, indicating a far more critical involvement in orchestrating brain development, plasticity, behaviour, and cognition. Various environmental factors, together with the individual genetic predispositions, confer an increased risk for neurodevelopmental and neuropsychiatric disorders, as well as neurodegenerative diseases that include autism spectrum disorders, schizophrenia, major depressive disorder, and Alzheimer's disease, across life. Microglia are highly sensitive to chronic psychological stress, inadequate diet, viral/bacterial infection, pollution, and insufficient or altered sleep, especially during critical developmental periods, but also throughout life. These environmental challenges can compromise microglial physiological functions, resulting notably in defective neuronal circuit wiring, altered brain functional connectivity, and the onset of behavioral deficits into adolescence, adulthood, and aging. This short review provides a historical and technical perspective, notably focused on my contribution to the field, on how environmental challenges affect microglia, particularly their physiological functions, and increase their diversity, which provides novel targets for intervention.
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Affiliation(s)
- Marie-Ève Tremblay
- Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, Québec, QC, Canada
- Molecular Medicine Department, Université Laval, Québec City, QC, Canada
- Department of Neurology and Neurosurgery, McGill University, Montréal, QC, Canada
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
- The Department of Biochemistry and Molecular Biology, The University of British Columbia, Vancouver, BC, Canada
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47
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Bordeleau M, Fernández de Cossío L, Lacabanne C, Savage JC, Vernoux N, Chakravarty M, Tremblay MÈ. Maternal high-fat diet modifies myelin organization, microglial interactions, and results in social memory and sensorimotor gating deficits in adolescent mouse offspring. Brain Behav Immun Health 2021; 15:100281. [PMID: 34589781 PMCID: PMC8474164 DOI: 10.1016/j.bbih.2021.100281] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 06/04/2021] [Indexed: 12/29/2022] Open
Abstract
Prenatal exposure to maternal high-fat diet (mHFD) acts as a risk factor for various neurodevelopmental alterations in the progeny. Recent studies in mice revealed that mHFD results in both neuroinflammation and hypomyelination in the exposed offspring. Microglia, the brain-resident macrophages, play crucial roles during brain development, notably by modulating oligodendrocyte populations and performing phagocytosis of myelin sheaths. Previously, we reported that mHFD modifies microglial phenotype (i.e., morphology, interactions with their microenvironment, transcripts) in the hippocampus of male and female offspring. In the current study, we further explored whether mHFD may induce myelination changes among the hippocampal-corpus callosum-prefrontal cortex pathway, and result in behavioral outcomes in adolescent offspring of the two sexes. To this end, female mice were fed with control chow or HFD for 4 weeks before mating, during gestation, and until weaning of their litter. Histological and ultrastructural analyses revealed an increased density of myelin associated with a reduced area of cytosolic myelin channels in the corpus callosum of mHFD-exposed male compared to female offspring. Transcripts of myelination-associated genes including Igf1 -a growth factor released by microglia- were also lower, specifically in the hippocampus (without changes in the prefrontal cortex) of adolescent male mouse offspring. These changes in myelin were not related to an altered density, distribution, or maturation of oligodendrocytes, instead we found that microglia within the corpus callosum of mHFD-exposed offspring showed reduced numbers of mature lysosomes and increased synaptic contacts, suggesting microglial implication in the modified myelination. At the behavioral level, both male and female mHFD-exposed adolescent offspring presented loss of social memory and sensorimotor gating deficits. These results together highlight the importance of studying oligodendrocyte-microglia crosstalk and its involvement in the long-term brain alterations that result from prenatal mHFD in offspring across sexes.
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Affiliation(s)
- Maude Bordeleau
- Integrated Program in Neuroscience, McGill University, Montréal, QC, Canada.,Axe Neurosciences, Centre de Recherche du CHU de Québec - Université Laval, Québec, QC, Canada
| | | | - Chloé Lacabanne
- Integrated Program in Neuroscience, McGill University, Montréal, QC, Canada
| | - Julie C Savage
- Axe Neurosciences, Centre de Recherche du CHU de Québec - Université Laval, Québec, QC, Canada
| | - Nathalie Vernoux
- Axe Neurosciences, Centre de Recherche du CHU de Québec - Université Laval, Québec, QC, Canada
| | - Mallar Chakravarty
- Integrated Program in Neuroscience, McGill University, Montréal, QC, Canada.,Cerebral Imaging Center, Douglas Mental Health University Institute, McGill University, Montréal, QC, Canada.,Department of Psychiatry, McGill University, Montréal, QC, Canada.,Department of Biological and Biomedical Engineering, McGill University, Montréal, QC, Canada
| | - Marie-Ève Tremblay
- Axe Neurosciences, Centre de Recherche du CHU de Québec - Université Laval, Québec, QC, Canada.,Département de Médecine Moléculaire, Université Laval, Québec, QC, Canada.,Department of Neurology and Neurosurgery, McGill University, Montréal, QC, Canada.,Division of Medical Sciences, University of Victoria, Victoria, BC, Canada.,Department of Biochemistry and Molecular Biology, Faculty of Medicine, The University of British Colombia, Vancouver, BC, Canada
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48
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Augusto-Oliveira M, Arrifano GP, Delage CI, Tremblay MÈ, Crespo-Lopez ME, Verkhratsky A. Plasticity of microglia. Biol Rev Camb Philos Soc 2021; 97:217-250. [PMID: 34549510 DOI: 10.1111/brv.12797] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 09/02/2021] [Accepted: 09/06/2021] [Indexed: 02/06/2023]
Abstract
Microglial cells are the scions of foetal macrophages which invade the neural tube early during embryogenesis. The nervous tissue environment instigates the phenotypic metamorphosis of foetal macrophages into idiosyncratic surveilling microglia, which are generally characterised by a small cell body and highly ramified motile processes that constantly scan the nervous tissue for signs of changes in homeostasis and allow microglia to perform crucial homeostatic functions. The surveilling microglial phenotype is evolutionarily conserved from early invertebrates to humans. Despite this evolutionary conservation, microglia show substantial heterogeneity in their gene and protein expression, as well as morphological appearance. These differences are age, region and context specific and reflect a high degree of plasticity underlying the life-long adaptation of microglia, supporting the exceptional adaptive capacity of the central nervous system. Microgliocytes are essential elements of cellular network formation and refinement in the developing nervous tissue. Several distinct patrolling modes of microglial processes contribute to the formation, modification, and pruning of synapses; to the support and protection of neurones through microglial-somatic junctions; and to the control of neuronal and axonal excitability by specific microglia-axonal contacts. In pathology, microglia undergo proliferation and reactive remodelling known as microgliosis, which is context dependent, yet represents an evolutionarily conserved defence response. Microgliosis results in the emergence of multiple disease and context-specific reactive states; in addition, neuropathology is associated with the appearance of specific protective or recovery microglial forms. In summary, the plasticity of microglia supports the development and functional activity of healthy nervous tissue and provides highly sophisticated defences against disease.
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Affiliation(s)
- Marcus Augusto-Oliveira
- Laboratório de Farmacologia Molecular, Instituto de Ciências Biológicas, Universidade Federal do Pará, 66075-110, Belém, Brazil
| | - Gabriela P Arrifano
- Laboratório de Farmacologia Molecular, Instituto de Ciências Biológicas, Universidade Federal do Pará, 66075-110, Belém, Brazil
| | - Charlotte Isabelle Delage
- Division of Medical Sciences, Medical Sciences Building, University of Victoria, Victoria, BC, V8P 5C2, Canada
| | - Marie-Ève Tremblay
- Division of Medical Sciences, Medical Sciences Building, University of Victoria, Victoria, BC, V8P 5C2, Canada.,Axe Neurosciences, Centre de Recherche du CHU de Québec-Université Laval, 2705 Boulevard Laurier, Québec City, QC, G1V 4G2, Canada.,Neurology and Neurosurgery Department, McGill University, 3801 University Street, Montreal, QC, H3A 2B4, Canada.,Department of Molecular Medicine, Université Laval, Pavillon Ferdinand-Vandry, Bureau 4835, 1050 Avenue de la Médecine, Québec City, QC, G1V 0A6, Canada.,Department of Biochemistry and Molecular Biology, The University of British Columbia, Life Sciences Center, 2350 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada
| | - Maria Elena Crespo-Lopez
- Laboratório de Farmacologia Molecular, Instituto de Ciências Biológicas, Universidade Federal do Pará, 66075-110, Belém, Brazil
| | - Alexei Verkhratsky
- Faculty of Life Sciences, The University of Manchester, Oxford Road, Manchester, M13 9PT, U.K.,Achucarro Center for Neuroscience, IKERBASQUE, 48011, Bilbao, Spain.,Department of Stem Cell Biology, State Research Institute Centre for Innovative Medicine, LT-01102, Vilnius, Lithuania
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49
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Wang J, Zhang Q, Lu Y, Dong Y, Dhandapani KM, Brann DW, Yu RK. Ganglioside GD3 is up-regulated in microglia and regulates phagocytosis following global cerebral ischemia. J Neurochem 2021; 158:737-752. [PMID: 34133773 DOI: 10.1111/jnc.15455] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 05/24/2021] [Accepted: 06/09/2021] [Indexed: 01/03/2023]
Abstract
Gangliosides, the major sialic-acid containing glycosphingolipids in the mammalian brain, play important roles in brain development and neural functions. Here, we show that the b-series ganglioside GD3 and its biosynthetic enzyme, GD3-synthase (GD3S), were up-regulated predominantly in the microglia of mouse hippocampus from 2 to 7 days following global cerebral ischemia (GCI). Interestingly, GD3S knockout (GD3S-KO) mice exhibited decreased hippocampal neuronal loss following GCI, as compared to wild-type (WT) mice. While comparable levels of astrogliosis and microglial proliferation were observed between WT and GD3S-KO mice, the phagocytic capacity of the GD3S-KO microglia was significantly compromised after GCI. At 2 and 4 days following GCI, the GD3S-KO microglia demonstrated decreased amoebic morphology, reduced neuronal material engulfment, and lower expression of the phagolysosome marker CD68, as compared to the WT microglia. Finally, by using a microglia-primary neuron co-culture model, we demonstrated that the GD3S-KO microglia isolated from mouse brains at 2 days after GCI are less neurotoxic to co-cultured hippocampal neurons than the WT-GCI microglia. Moreover, the percentage of microglia with engulfed neuronal elements in the co-cultured wells was also significantly decreased in the GD3S-KO mice after GCI. Interestingly, the impaired phagocytic capacity of GD3S-KO microglia could be partially restored by pre-treatment with exogenous ganglioside GD3. Altogether, this study provides functional evidence that ganglioside GD3 regulates phagocytosis by microglia in an ischemic stroke model. Our data also suggest that the GD3-linked microglial phagocytosis may contribute to the mechanism of delayed neuronal death following ischemic brain injury.
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Affiliation(s)
- Jing Wang
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Quanguang Zhang
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Yujiao Lu
- Department of Neurosurgery, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Yan Dong
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Krishnan M Dhandapani
- Department of Neurosurgery, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Darrell W Brann
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Robert K Yu
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA, USA
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50
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Choi S, Guo L, Cordeiro MF. Retinal and Brain Microglia in Multiple Sclerosis and Neurodegeneration. Cells 2021; 10:cells10061507. [PMID: 34203793 PMCID: PMC8232741 DOI: 10.3390/cells10061507] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Revised: 05/28/2021] [Accepted: 06/11/2021] [Indexed: 12/24/2022] Open
Abstract
Microglia are the resident immune cells of the central nervous system (CNS), including the retina. Similar to brain microglia, retinal microglia are responsible for retinal surveillance, rapidly responding to changes in the environment by altering morphotype and function. Microglia become activated in inflammatory responses in neurodegenerative diseases, including multiple sclerosis (MS). When activated by stress stimuli, retinal microglia change their morphology and activity, with either beneficial or harmful consequences. In this review, we describe characteristics of CNS microglia, including those in the retina, with a focus on their morphology, activation states and function in health, ageing, MS and other neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, glaucoma and retinitis pigmentosa, to highlight their activity in disease. We also discuss contradictory findings in the literature and the potential ways of reducing inconsistencies in future by using standardised methodology, e.g., automated algorithms, to enable a more comprehensive understanding of this exciting area of research.
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Affiliation(s)
- Soyoung Choi
- UCL Institute of Ophthalmology, London EC1V 9EL, UK; (S.C.); (L.G.)
| | - Li Guo
- UCL Institute of Ophthalmology, London EC1V 9EL, UK; (S.C.); (L.G.)
| | - Maria Francesca Cordeiro
- UCL Institute of Ophthalmology, London EC1V 9EL, UK; (S.C.); (L.G.)
- ICORG, Imperial College London, London NW1 5QH, UK
- Correspondence:
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