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Pocock J, Vasilopoulou F, Svensson E, Cosker K. Microglia and TREM2. Neuropharmacology 2024; 257:110020. [PMID: 38821351 DOI: 10.1016/j.neuropharm.2024.110020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Revised: 05/20/2024] [Accepted: 05/28/2024] [Indexed: 06/02/2024]
Abstract
TREM2 is a membrane receptor solely expressed on microglia in normal brain. In this review we outline recent advances in TREM2 biology and its implications for microglial function, with particular emphasis on findings from iPSC-derived microglia (iMG) expressing TREM2 loss-of-function mutations. Alterations in receptor proximal and distal signalling underlie TREM2 risk variants linked to neurodegenerative disease, principally NH-linked FTD, and late-onset AD, but emerging data suggest roles for TREM2 in PD, MS and ALS. TREM2 downstream functions include phagocytosis of myelin debris, amyloid beta peptides, and phosphatidylserine-expressing cells (resulting from damage or stress). Microglial survival, migration, DAMP signalling, inflammasome activation, and intercellular signalling including tau spreading via exosomes, as well as roles for sTREM2 in protection and as a biomarker are discussed. The role of TREM2 in metabolic homeostasis, and immunometabolic switching are discussed regarding microglial responses to damage and protection. The use of iPSC models to investigate the role of TREM2 in AD, PD, MS, ALS, and other neurodegenerative diseases could prove invaluable due to their ability to recapitulate human pathology, allowing a full understanding of TREM2 and microglial involvement in the underlying disease mechanisms and progression. This article is part of the Special Issue on "Microglia".
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Affiliation(s)
- Jennifer Pocock
- Department of Neuroinflammation, And Department of Neurodegenerative Disease, Queen Square Institute of Neurology, University College London, 1 Wakefield Street, London, WC1N1PJ, UK.
| | - Foteini Vasilopoulou
- Department of Neuroinflammation, And Department of Neurodegenerative Disease, Queen Square Institute of Neurology, University College London, 1 Wakefield Street, London, WC1N1PJ, UK
| | - Elina Svensson
- Department of Neuroinflammation, And Department of Neurodegenerative Disease, Queen Square Institute of Neurology, University College London, 1 Wakefield Street, London, WC1N1PJ, UK
| | - Katharina Cosker
- Department of Neuroinflammation, And Department of Neurodegenerative Disease, Queen Square Institute of Neurology, University College London, 1 Wakefield Street, London, WC1N1PJ, UK
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Jury-Garfe N, Redding-Ochoa J, You Y, Martínez P, Karahan H, Chimal-Juárez E, Johnson TS, Zhang J, Resnick S, Kim J, Troncoso JC, Lasagna-Reeves CA. Enhanced microglial dynamics and a paucity of tau seeding in the amyloid plaque microenvironment contribute to cognitive resilience in Alzheimer's disease. Acta Neuropathol 2024; 148:15. [PMID: 39102080 DOI: 10.1007/s00401-024-02775-1] [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: 05/21/2024] [Revised: 07/09/2024] [Accepted: 07/26/2024] [Indexed: 08/06/2024]
Abstract
Asymptomatic Alzheimer's disease (AsymAD) describes the status of individuals with preserved cognition but identifiable Alzheimer's disease (AD) brain pathology (i.e., beta-amyloid (Aβ) deposits, neuritic plaques, and neurofibrillary tangles) at autopsy. In this study, we investigated the postmortem brains of a cohort of AsymAD subjects to gain insight into the mechanisms underlying resilience to AD pathology and cognitive decline. Our results showed that AsymAD cases exhibit enrichment in core plaques, decreased filamentous plaque accumulation, and increased plaque-surrounding microglia. Less pathological tau aggregation in dystrophic neurites was found in AsymAD brains than in AD brains, and tau seeding activity was comparable to that in healthy brains. We used spatial transcriptomics to characterize the plaque niche further and revealed autophagy, endocytosis, and phagocytosis as the pathways associated with the genes upregulated in the AsymAD plaque niche. Furthermore, the levels of ARP2 and CAP1, which are actin-based motility proteins that participate in the dynamics of actin filaments to allow cell motility, were increased in the microglia surrounding amyloid plaques in AsymAD cases. Our findings suggest that the amyloid-plaque microenvironment in AsymAD cases is characterized by the presence of microglia with highly efficient actin-based cell motility mechanisms and decreased tau seeding compared with that in AD brains. These two mechanisms can potentially protect against the toxic cascade initiated by Aβ, preserving brain health, and slowing AD pathology progression.
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Affiliation(s)
- Nur Jury-Garfe
- Stark Neurosciences Research Institute, Indiana University School of Medicine, Neurosciences Research Building 214G, 320 West 15th Street, Indianapolis, IN, 46202, USA
- Department of Anatomy, Cell Biology and Physiology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Javier Redding-Ochoa
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Yanwen You
- Stark Neurosciences Research Institute, Indiana University School of Medicine, Neurosciences Research Building 214G, 320 West 15th Street, Indianapolis, IN, 46202, USA
- Department of Anatomy, Cell Biology and Physiology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Pablo Martínez
- Stark Neurosciences Research Institute, Indiana University School of Medicine, Neurosciences Research Building 214G, 320 West 15th Street, Indianapolis, IN, 46202, USA
- Department of Anatomy, Cell Biology and Physiology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Hande Karahan
- Stark Neurosciences Research Institute, Indiana University School of Medicine, Neurosciences Research Building 214G, 320 West 15th Street, Indianapolis, IN, 46202, USA
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, USA
| | - Enrique Chimal-Juárez
- Stark Neurosciences Research Institute, Indiana University School of Medicine, Neurosciences Research Building 214G, 320 West 15th Street, Indianapolis, IN, 46202, USA
- Department of Anatomy, Cell Biology and Physiology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Travis S Johnson
- Department of Biostatistics and Health Data Science, Indiana University School of Medicine, Indianapolis, USA
| | - Jie Zhang
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, USA
- Center for Computational Biology and Bioinformatics, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Susan Resnick
- Laboratory of Behavioral Neuroscience, National Institute on Aging and National Institute of Health, Baltimore, MD, USA
| | - Jungsu Kim
- Stark Neurosciences Research Institute, Indiana University School of Medicine, Neurosciences Research Building 214G, 320 West 15th Street, Indianapolis, IN, 46202, USA
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, USA
| | - Juan C Troncoso
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Cristian A Lasagna-Reeves
- Stark Neurosciences Research Institute, Indiana University School of Medicine, Neurosciences Research Building 214G, 320 West 15th Street, Indianapolis, IN, 46202, USA.
- Department of Anatomy, Cell Biology and Physiology, Indiana University School of Medicine, Indianapolis, IN, USA.
- Center for Computational Biology and Bioinformatics, Indiana University School of Medicine, Indianapolis, IN, USA.
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Cordeiro A, Gomes C, Bicker J, Fortuna A. Aging and cognitive resilience: Molecular mechanisms as new potential therapeutic targets. Drug Discov Today 2024; 29:104093. [PMID: 38992420 DOI: 10.1016/j.drudis.2024.104093] [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: 04/18/2024] [Revised: 06/25/2024] [Accepted: 07/04/2024] [Indexed: 07/13/2024]
Abstract
As the global population ages, the need to prolong lifespan and healthspan becomes increasingly imperative. Understanding the molecular determinants underlying cognitive resilience, together with changes during aging and the (epi)genetic factors that predispose an individual to decreased cognitive resilience, open avenues for researching novel therapies. This review provides a critical and timely appraisal of the molecular mechanisms underlying cognitive resilience, framed within a critical analysis of emerging therapeutic strategies to mitigate age-related cognitive decline. Significant insights from both animals and human subjects are discussed herein, directed either toward active pharmaceutical ingredients (drug repositioning or macromolecules), or, alternatively, advanced cellular therapies.
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Affiliation(s)
- Ana Cordeiro
- Laboratory of Pharmacology, Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal
| | - Catarina Gomes
- Laboratory of Pharmacology, Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal; CIBIT - Coimbra Institute for Biomedical Imaging and Translational Research, University of Coimbra, Coimbra, Portugal
| | - Joana Bicker
- Laboratory of Pharmacology, Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal; CIBIT - Coimbra Institute for Biomedical Imaging and Translational Research, University of Coimbra, Coimbra, Portugal
| | - Ana Fortuna
- Laboratory of Pharmacology, Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal; CIBIT - Coimbra Institute for Biomedical Imaging and Translational Research, University of Coimbra, Coimbra, Portugal.
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Guptarak J, Scaduto P, Tumurbaatar B, Zhang WR, Jupiter D, Taglialatela G, Fracassi A. Cognitive integrity in Non-Demented Individuals with Alzheimer's Neuropathology is associated with preservation and remodeling of dendritic spines. Alzheimers Dement 2024; 20:4677-4691. [PMID: 38829680 PMCID: PMC11247701 DOI: 10.1002/alz.13900] [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: 01/26/2024] [Revised: 04/23/2024] [Accepted: 04/24/2024] [Indexed: 06/05/2024]
Abstract
INTRODUCTION Individuals referred to as Non-Demented with Alzheimer's Neuropathology (NDAN) exhibit cognitive resilience despite presenting Alzheimer's disease (AD) histopathological signs. Investigating the mechanisms behind this resilience may unveil crucial insights into AD resistance. METHODS DiI labeling technique was used to analyze dendritic spine morphology in control (CTRL), AD, and NDAN post mortem frontal cortex, particularly focusing on spine types near and far from amyloid beta (Aβ) plaques. RESULTS NDAN subjects displayed a higher spine density in regions distant from Aβ plaques versus AD patients. In distal areas from the plaques, NDAN individuals exhibited more immature spines, while AD patients had a prevalence of mature spines. Additionally, our examination of levels of Peptidyl-prolyl cis-trans isomerase NIMA-interacting 1 (Pin1), a protein associated with synaptic plasticity and AD, showed significantly lower expression in AD versus NDAN and CTRL. DISCUSSION These results suggest that NDAN individuals undergo synaptic remodeling, potentially facilitated by Pin1, serving as a compensatory mechanism to preserve cognitive function despite AD pathology. HIGHLIGHTS Spine density is reduced near Aβ plaques compared to the distal area in CTRL, AD, and NDAN dendrites. NDAN shows higher spine density than AD in areas far from Aβ plaques. Far from Aβ plaques, NDAN has a higher density of immature spines, AD a higher density of mature spines. AD individuals show significantly lower levels of Pin1 compared to NDAN and CTRL.
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Affiliation(s)
- Jutatip Guptarak
- Department of Neurology, Mitchell Center for Neurodegenerative Disease, University of Texas Medical Branch at GalvestonGalvestonTexasUSA
| | - Pietro Scaduto
- Department of Neurology, Mitchell Center for Neurodegenerative Disease, University of Texas Medical Branch at GalvestonGalvestonTexasUSA
| | - Batbayar Tumurbaatar
- Department of Neurology, Mitchell Center for Neurodegenerative Disease, University of Texas Medical Branch at GalvestonGalvestonTexasUSA
| | - Wen Ru Zhang
- Department of Neurology, Mitchell Center for Neurodegenerative Disease, University of Texas Medical Branch at GalvestonGalvestonTexasUSA
| | - Daniel Jupiter
- Department of Biostatistics and Data Science, University of Texas Medical Branch at GalvestonGalvestonTexasUSA
| | - Giulio Taglialatela
- Department of Neurology, Mitchell Center for Neurodegenerative Disease, University of Texas Medical Branch at GalvestonGalvestonTexasUSA
| | - Anna Fracassi
- Department of Neurology, Mitchell Center for Neurodegenerative Disease, University of Texas Medical Branch at GalvestonGalvestonTexasUSA
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Fongsaran C, Jirakanwisal K, Peng BH, Fracassi A, Taglialatela G, Dineley KT, Paessler S, Cisneros IE. Arbovirus infection increases the risk for the development of neurodegenerative disease pathology in the murine model. Brain Behav Immun Health 2024; 38:100780. [PMID: 38706571 PMCID: PMC11067009 DOI: 10.1016/j.bbih.2024.100780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 03/04/2024] [Accepted: 04/23/2024] [Indexed: 05/07/2024] Open
Abstract
Alzheimer's disease is classified as a progressive disorder resulting from protein misfolding, also known as proteinopathies. Proteinopathies include synucleinopathies triggered by misfolded amyloid α-synuclein, tauopathies triggered by misfolded tau, and amyloidopathies triggered by misfolded amyloid of which Alzheimer's disease (β-amyloid) is most prevalent. Most neurodegenerative diseases (>90%) are not due to dominantly inherited genetic causes. Instead, it is thought that the risk for disease is a complicated interaction between inherited and environmental risk factors that, with age, drive pathology that ultimately results in neurodegeneration and disease onset. Since it is increasingly appreciated that encephalitic viral infections can have profoundly detrimental neurological consequences long after the acute infection has resolved, we tested the hypothesis that viral encephalitis exacerbates the pathological profile of protein-misfolding diseases. Using a robust, reproducible, and well-characterized mouse model for β-amyloidosis, Tg2576, we studied the contribution of alphavirus-induced encephalitis (TC-83 strain of VEEV to model alphavirus encephalitis viruses) on the progression of neurodegenerative pathology. We longitudinally evaluated neurological, neurobehavioral, and cognitive levels, followed by a post-mortem analysis of brain pathology focusing on neuroinflammation. We found more severe cognitive deficits and brain pathology in Tg2576 mice inoculated with TC-83 than in their mock controls. These data set the groundwork to investigate sporadic Alzheimer's disease and treatment interventions for this infectious disease risk factor.
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Affiliation(s)
- Chanida Fongsaran
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, USA
- Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX, USA
- Neuroinfectious Diseases, University of Texas Medical Branch, Galveston, TX, USA
| | - Krit Jirakanwisal
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, USA
- Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX, USA
- Neuroinfectious Diseases, University of Texas Medical Branch, Galveston, TX, USA
| | - Bi-Hung Peng
- Department of Neurobiology, University of Texas Medical Branch, Galveston, TX, USA
| | - Anna Fracassi
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, University of Texas Medical Branch, Galveston, TX, USA
| | - Giulio Taglialatela
- Neuroinfectious Diseases, University of Texas Medical Branch, Galveston, TX, USA
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, University of Texas Medical Branch, Galveston, TX, USA
| | - Kelly T. Dineley
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, University of Texas Medical Branch, Galveston, TX, USA
- Center for Addiction Sciences and Therapeutics, University of Texas Medical Branch, Galveston, TX, USA
| | - Slobodan Paessler
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, USA
- Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX, USA
| | - Irma E. Cisneros
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, USA
- Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX, USA
- Neuroinfectious Diseases, University of Texas Medical Branch, Galveston, TX, USA
- Center for Addiction Sciences and Therapeutics, University of Texas Medical Branch, Galveston, TX, USA
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Pumo A, Legeay S. The dichotomous activities of microglia: A potential driver for phenotypic heterogeneity in Alzheimer's disease. Brain Res 2024; 1832:148817. [PMID: 38395249 DOI: 10.1016/j.brainres.2024.148817] [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: 10/30/2023] [Revised: 01/28/2024] [Accepted: 02/19/2024] [Indexed: 02/25/2024]
Abstract
Alzheimer's disease (AD) is a leading cause of dementia, characterized by two defining neuropathological hallmarks: amyloid plaques composed of Aβ aggregates and neurofibrillary pathology. Recent research suggests that microglia have both beneficial and detrimental effects in the development of AD. A new theory proposes that microglia play a beneficial role in the early stages of the disease but become harmful in later stages. Further investigations are needed to gain a comprehensive understanding of this shift in microglia's function. This transition is likely influenced by specific conditions, including spatial, temporal, and transcriptional factors, which ultimately lead to the deterioration of microglial functionality. Additionally, recent studies have also highlighted the potential influence of microglia diversity on the various manifestations of AD. By deciphering the multiple states of microglia and the phenotypic heterogeneity in AD, significant progress can be made towards personalized medicine and better treatment outcomes for individuals affected by AD.
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Affiliation(s)
- Anna Pumo
- Université d'Angers, Faculté de Santé, Département Pharmacie, 16, Boulevard Daviers, Angers 49045, France.
| | - Samuel Legeay
- Université d'Angers, Faculté de Santé, Département Pharmacie, 16, Boulevard Daviers, Angers 49045, France; Univ Angers, Inserm, CNRS, MINT, SFR ICAT, Angers F-49000, France
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Zhang X, Li H, Tang L, Zhu B, Yang W, Li M, Zhao Y. Photobiomodulation therapy enhances neural differentiation of dental pulp stem cells via ERK1/2 signaling pathway. Photochem Photobiol 2024; 100:646-655. [PMID: 37815161 DOI: 10.1111/php.13864] [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: 08/17/2023] [Revised: 09/25/2023] [Accepted: 09/27/2023] [Indexed: 10/11/2023]
Abstract
Photobiomodulation therapy (PBMT) is the application of a low-level laser device to generate physiological changes and provide therapeutic effects. Till now, the effects of PBMT on the neural differentiation of mesenchymal stem cells have been rarely reported. Herein, the potential effect and mechanism of PBMT on the neural differentiation of dental pulp stem cells (DPSCs) were preliminarily investigated in our research. The optimal dose of 3.75 J/cm2 was first screened for use in the following neural-inducing studies. Then, DPSCs were cultured in neural induction medium and treated with laser irradiation for 7 days. From the results of morphology and immunofluorescence, we found that irradiation promoted the formation of neural stem cell-like spheroids derived from DPSCs and enhanced potential neural differentiation. Furthermore, neural differentiation gene expressions of Nestin, microtubule-associated protein-2, and neural cell adhesion molecule were increased after PBMT irradiation. The protein expressions of class III β-tubulin and neurogenic differentiation factor 1 were also improved. Meanwhile, the involvement of extracellular signal-regulated kinase (ERK1/2) was investigated by western blot. Our study showed that the neural differentiation of DPSCs was promoted by PBMT, and the underlying mechanism in this process was associated with activating the ERK1/2 signaling pathway.
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Affiliation(s)
- Xinran Zhang
- Department of Stomatology, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Haotian Li
- Department of Orthopedics, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Lu Tang
- Department of Stomatology, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Biao Zhu
- Department of Stomatology, Fu Xing Hospital, Capital Medical University, Beijing, China
| | - Wenwen Yang
- Department of Stomatology, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Miao Li
- Department of Stomatology, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Ying Zhao
- Department of Stomatology, Xuanwu Hospital, Capital Medical University, Beijing, China
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de Vries LE, Jongejan A, Monteiro Fortes J, Balesar R, Rozemuller AJM, Moerland PD, Huitinga I, Swaab DF, Verhaagen J. Gene-expression profiling of individuals resilient to Alzheimer's disease reveals higher expression of genes related to metallothionein and mitochondrial processes and no changes in the unfolded protein response. Acta Neuropathol Commun 2024; 12:68. [PMID: 38664739 PMCID: PMC11046840 DOI: 10.1186/s40478-024-01760-9] [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: 01/10/2024] [Accepted: 03/10/2024] [Indexed: 04/28/2024] Open
Abstract
Some individuals show a discrepancy between cognition and the amount of neuropathological changes characteristic for Alzheimer's disease (AD). This phenomenon has been referred to as 'resilience'. The molecular and cellular underpinnings of resilience remain poorly understood. To obtain an unbiased understanding of the molecular changes underlying resilience, we investigated global changes in gene expression in the superior frontal gyrus of a cohort of cognitively and pathologically well-defined AD patients, resilient individuals and age-matched controls (n = 11-12 per group). 897 genes were significantly altered between AD and control, 1121 between resilient and control and 6 between resilient and AD. Gene set enrichment analysis (GSEA) revealed that the expression of metallothionein (MT) and of genes related to mitochondrial processes was higher in the resilient donors. Weighted gene co-expression network analysis (WGCNA) identified gene modules related to the unfolded protein response, mitochondrial processes and synaptic signaling to be differentially associated with resilience or dementia. As changes in MT, mitochondria, heat shock proteins and the unfolded protein response (UPR) were the most pronounced changes in the GSEA and/or WGCNA, immunohistochemistry was used to further validate these processes. MT was significantly increased in astrocytes in resilient individuals. A higher proportion of the mitochondrial gene MT-CO1 was detected outside the cell body versus inside the cell body in the resilient compared to the control group and there were higher levels of heat shock protein 70 (HSP70) and X-box-binding protein 1 spliced (XBP1s), two proteins related to heat shock proteins and the UPR, in the AD donors. Finally, we show evidence for putative sex-specific alterations in resilience, including gene expression differences related to autophagy in females compared to males. Taken together, these results show possible mechanisms involving MTs, mitochondrial processes and the UPR by which individuals might maintain cognition despite the presence of AD pathology.
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Affiliation(s)
- Luuk E de Vries
- Department of Neuroregeneration, Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences, Meibergdreef 47, 1105 BA, Amsterdam, The Netherlands.
| | - Aldo Jongejan
- Amsterdam UMC Location University of Amsterdam, Epidemiology and Data Science, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
- Amsterdam Public Health, Methodology, Amsterdam, The Netherlands
- Amsterdam Infection and Immunity, Inflammatory Diseases, Amsterdam, The Netherlands
| | - Jennifer Monteiro Fortes
- Department of Neuropsychiatric Disorders, Netherlands Institute for Neuroscience, Institute of the Royal Netherlands Academy of Arts and Sciences, Meibergdreef 47, 1105 BA, Amsterdam, The Netherlands
| | - Rawien Balesar
- Department of Neuropsychiatric Disorders, Netherlands Institute for Neuroscience, Institute of the Royal Netherlands Academy of Arts and Sciences, Meibergdreef 47, 1105 BA, Amsterdam, The Netherlands
| | - Annemieke J M Rozemuller
- Department of Pathology, Amsterdam Neuroscience, Amsterdam UMC - Location VUmc, Amsterdam, The Netherlands
| | - Perry D Moerland
- Amsterdam UMC Location University of Amsterdam, Epidemiology and Data Science, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
- Amsterdam Public Health, Methodology, Amsterdam, The Netherlands
- Amsterdam Infection and Immunity, Inflammatory Diseases, Amsterdam, The Netherlands
| | - Inge Huitinga
- Department of Neuroimmunology, Netherlands Institute for Neuroscience, Institute of the Royal Netherlands Academy of Arts and Sciences, Meibergdreef 47, 1105 BA, Amsterdam, The Netherlands
- Center for Neuroscience, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - Dick F Swaab
- Department of Neuropsychiatric Disorders, Netherlands Institute for Neuroscience, Institute of the Royal Netherlands Academy of Arts and Sciences, Meibergdreef 47, 1105 BA, Amsterdam, The Netherlands
| | - Joost Verhaagen
- Department of Neuroregeneration, Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences, Meibergdreef 47, 1105 BA, Amsterdam, The Netherlands.
- Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU University, Boelelaan 1085, 1081 HV, Amsterdam, The Netherlands.
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Luo YX, Yang LL, Yao XQ. Gut microbiota-host lipid crosstalk in Alzheimer's disease: implications for disease progression and therapeutics. Mol Neurodegener 2024; 19:35. [PMID: 38627829 PMCID: PMC11020986 DOI: 10.1186/s13024-024-00720-0] [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: 12/12/2023] [Accepted: 03/18/2024] [Indexed: 04/19/2024] Open
Abstract
Trillions of intestinal bacteria in the human body undergo dynamic transformations in response to physiological and pathological changes. Alterations in their composition and metabolites collectively contribute to the progression of Alzheimer's disease. The role of gut microbiota in Alzheimer's disease is diverse and complex, evidence suggests lipid metabolism may be one of the potential pathways. However, the mechanisms that gut microbiota mediate lipid metabolism in Alzheimer's disease pathology remain unclear, necessitating further investigation for clarification. This review highlights the current understanding of how gut microbiota disrupts lipid metabolism and discusses the implications of these discoveries in guiding strategies for the prevention or treatment of Alzheimer's disease based on existing data.
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Affiliation(s)
- Ya-Xi Luo
- Department of Rehabilitation, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Ling-Ling Yang
- Department of Rehabilitation, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Xiu-Qing Yao
- Department of Rehabilitation, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China.
- Chongqing Municipality Clinical Research Center for Geriatric Medicine, Chongqing, China.
- Department of Rehabilitation Therapy, Chongqing Medical University, Chongqing, China.
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de Vries LE, Huitinga I, Kessels HW, Swaab DF, Verhaagen J. The concept of resilience to Alzheimer's Disease: current definitions and cellular and molecular mechanisms. Mol Neurodegener 2024; 19:33. [PMID: 38589893 PMCID: PMC11003087 DOI: 10.1186/s13024-024-00719-7] [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: 08/23/2023] [Accepted: 03/20/2024] [Indexed: 04/10/2024] Open
Abstract
Some individuals are able to maintain their cognitive abilities despite the presence of significant Alzheimer's Disease (AD) neuropathological changes. This discrepancy between cognition and pathology has been labeled as resilience and has evolved into a widely debated concept. External factors such as cognitive stimulation are associated with resilience to AD, but the exact cellular and molecular underpinnings are not completely understood. In this review, we discuss the current definitions used in the field, highlight the translational approaches used to investigate resilience to AD and summarize the underlying cellular and molecular substrates of resilience that have been derived from human and animal studies, which have received more and more attention in the last few years. From these studies the picture emerges that resilient individuals are different from AD patients in terms of specific pathological species and their cellular reaction to AD pathology, which possibly helps to maintain cognition up to a certain tipping point. Studying these rare resilient individuals can be of great importance as it could pave the way to novel therapeutic avenues for AD.
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Affiliation(s)
- Luuk E de Vries
- Department of Neuroregeneration, Netherlands Institute for Neuroscience, Institute of the Royal Netherlands Academy of Arts and Sciences, 1105 BA, Amsterdam, The Netherlands.
| | - Inge Huitinga
- Department of Neuroimmunology, Netherlands Institute for Neuroscience, Institute of the Royal Netherlands Academy of Arts and Sciences, 1105 BA, Amsterdam, The Netherlands
| | - Helmut W Kessels
- Swammerdam Institute for Life Sciences, Amsterdam Neuroscience, University of Amsterdam, 1098 XH, Amsterdam, the Netherlands
| | - Dick F Swaab
- Department of Neuropsychiatric Disorders, Netherlands Institute for Neuroscience, an Institute of the Royal Netherlands Academy of Arts and Sciences, 1105 BA, Amsterdam, Netherlands
| | - Joost Verhaagen
- Department of Neuroregeneration, Netherlands Institute for Neuroscience, Institute of the Royal Netherlands Academy of Arts and Sciences, 1105 BA, Amsterdam, The Netherlands
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, VU University, Boelelaan 1085, 1081 HV, Amsterdam, The Netherlands
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Soares ÉN, Costa ACDS, Ferrolho GDJ, Ureshino RP, Getachew B, Costa SL, da Silva VDA, Tizabi Y. Nicotinic Acetylcholine Receptors in Glial Cells as Molecular Target for Parkinson's Disease. Cells 2024; 13:474. [PMID: 38534318 DOI: 10.3390/cells13060474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 03/02/2024] [Accepted: 03/05/2024] [Indexed: 03/28/2024] Open
Abstract
Parkinson's disease (PD) is a progressive neurodegenerative disease characterized by resting tremor, bradykinesia, rigidity, and postural instability that also includes non-motor symptoms such as mood dysregulation. Dopamine (DA) is the primary neurotransmitter involved in this disease, but cholinergic imbalance has also been implicated. Current intervention in PD is focused on replenishing central DA, which provides remarkable temporary symptomatic relief but does not address neuronal loss and the progression of the disease. It has been well established that neuronal nicotinic cholinergic receptors (nAChRs) can regulate DA release and that nicotine itself may have neuroprotective effects. Recent studies identified nAChRs in nonneuronal cell types, including glial cells, where they may regulate inflammatory responses. Given the crucial role of neuroinflammation in dopaminergic degeneration and the involvement of microglia and astrocytes in this response, glial nAChRs may provide a novel therapeutic target in the prevention and/or treatment of PD. In this review, following a brief discussion of PD, we focus on the role of glial cells and, specifically, their nAChRs in PD pathology and/or treatment.
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Affiliation(s)
- Érica Novaes Soares
- Laboratory of Neurochemistry and Cell Biology, Department of Biochemistry and Biophysics, Institute of Health Sciences, Federal University of Bahia, Salvador 40110-902, BA, Brazil
| | - Ana Carla Dos Santos Costa
- Laboratory of Neurochemistry and Cell Biology, Department of Biochemistry and Biophysics, Institute of Health Sciences, Federal University of Bahia, Salvador 40110-902, BA, Brazil
| | - Gabriel de Jesus Ferrolho
- Laboratory of Neurochemistry and Cell Biology, Department of Biochemistry and Biophysics, Institute of Health Sciences, Federal University of Bahia, Salvador 40110-902, BA, Brazil
- Laboratory of Neurosciences, Institute of Health Sciences, Federal University of Bahia, Salvador 40110-902, BA, Brazil
| | - Rodrigo Portes Ureshino
- Department of Biological Sciences, Universidade Federal de São Paulo, Diadema 09961-400, SP, Brazil
- Laboratory of Molecular and Translational Endocrinology, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo 04039-032, SP, Brazil
| | - Bruk Getachew
- Department of Pharmacology, College of Medicine, Howard University, 520 W Street NW, Washington, DC 20059, USA
| | - Silvia Lima Costa
- Laboratory of Neurochemistry and Cell Biology, Department of Biochemistry and Biophysics, Institute of Health Sciences, Federal University of Bahia, Salvador 40110-902, BA, Brazil
| | - Victor Diogenes Amaral da Silva
- Laboratory of Neurochemistry and Cell Biology, Department of Biochemistry and Biophysics, Institute of Health Sciences, Federal University of Bahia, Salvador 40110-902, BA, Brazil
- Laboratory of Neurosciences, Institute of Health Sciences, Federal University of Bahia, Salvador 40110-902, BA, Brazil
| | - Yousef Tizabi
- Department of Pharmacology, College of Medicine, Howard University, 520 W Street NW, Washington, DC 20059, USA
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12
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Zgorzynska E. TREM2 in Alzheimer's disease: Structure, function, therapeutic prospects, and activation challenges. Mol Cell Neurosci 2024; 128:103917. [PMID: 38244651 DOI: 10.1016/j.mcn.2024.103917] [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: 08/03/2023] [Revised: 01/12/2024] [Accepted: 01/15/2024] [Indexed: 01/22/2024] Open
Abstract
Triggering receptor expressed on myeloid cells 2 (TREM2) is a membrane glycoprotein that plays a crucial role in the regulation of microglial survival, activation, phagocytosis, as well as in the maintenance of brain homeostasis and the inflammatory response to injury or neurodegeneration. This review provides a comprehensive overview of TREM2 structure and functions, highlighting the role of its variants in the development and progression of Alzheimer's disease (AD), a devastating neurodegenerative disease that affects millions of people worldwide. Additionally, the article discusses the potential of TREM2 as a therapeutic target in AD, analyzing the current state of research and future prospects. Given the significant challenges associated with the activation of TREM2, particularly due to its diverse isoforms and the delicate balance required to modulate the immune response without triggering hyperactivation, this review aims to enhance our understanding of TREM2 in AD and inspire further research into this promising yet challenging therapeutic target.
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Affiliation(s)
- Emilia Zgorzynska
- Department of Cell-to-Cell Communication, Medical University of Lodz, Mazowiecka 6/8, 92-215 Lodz, Poland.
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13
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Wen L, Bi D, Shen Y. Complement-mediated synapse loss in Alzheimer's disease: mechanisms and involvement of risk factors. Trends Neurosci 2024; 47:135-149. [PMID: 38129195 DOI: 10.1016/j.tins.2023.11.010] [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: 06/20/2023] [Revised: 10/25/2023] [Accepted: 11/27/2023] [Indexed: 12/23/2023]
Abstract
The complement system is increasingly recognized as a key player in the synapse loss and cognitive impairments observed in Alzheimer's disease (AD). In particular, the process of complement-dependent synaptic pruning through phagocytosis is over-activated in AD brains, driving detrimental excessive synapse elimination and contributing to synapse loss, which is the strongest neurobiological correlate of cognitive impairments in AD. Herein we review recent advances in characterizing complement-mediated synapse loss in AD, summarize the underlying mechanisms, and discuss the possible involvement of AD risk factors such as aging and various risk genes. We conclude with an overview of key questions that remain to be addressed.
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Affiliation(s)
- Lang Wen
- Department of Neurology and Institute on Aging and Brain Disorders, The First Affiliated Hospital of USTC, Neurodegenerative Disease Research Center, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230026, China
| | - Danlei Bi
- Department of Neurology and Institute on Aging and Brain Disorders, The First Affiliated Hospital of USTC, Neurodegenerative Disease Research Center, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230026, China; Anhui Province Key Laboratory of Biomedical Aging Research, University of Science and Technology of China, Hefei, 230026, China; Institute of Artificial Intelligence, Hefei Comprehensive National Science Center, Hefei, 230026, China; CAS Key Laboratory of Brain Function and Disease, School of Life Sciences, University of Science and Technology of China, Hefei, 230026, China; Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China.
| | - Yong Shen
- Department of Neurology and Institute on Aging and Brain Disorders, The First Affiliated Hospital of USTC, Neurodegenerative Disease Research Center, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230026, China; Anhui Province Key Laboratory of Biomedical Aging Research, University of Science and Technology of China, Hefei, 230026, China; CAS Key Laboratory of Brain Function and Disease, School of Life Sciences, University of Science and Technology of China, Hefei, 230026, China; Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China.
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14
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Teipel SJ, Dyrba M, Kleineidam L, Brosseron F, Levin F, Bruno D, Buerger K, Cosma N, Schneider L, Düzel E, Glanz W, Fliessbach K, Janowitz D, Kilimann I, Laske C, Munk MH, Maier F, Peters O, Pomara N, Perneczky R, Rauchmann B, Priller J, Ramirez A, Roy N, Schneider A, Spottke A, Spruth EJ, Roeske S, Wagner M, Wiltfang J, Wolfsgruber S, Bartels C, Jessen F, Heneka MT. Association of latent factors of neuroinflammation with Alzheimer's disease pathology and longitudinal cognitive decline. ALZHEIMER'S & DEMENTIA (AMSTERDAM, NETHERLANDS) 2024; 16:e12510. [PMID: 38213951 PMCID: PMC10781650 DOI: 10.1002/dad2.12510] [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] [Received: 05/26/2023] [Revised: 11/06/2023] [Accepted: 11/10/2023] [Indexed: 01/13/2024]
Abstract
INTRODUCTION We investigated the association of inflammatory mechanisms with markers of Alzheimer's disease (AD) pathology and rates of cognitive decline in the AD spectrum. METHODS We studied 296 cases from the Deutsches Zentrum für Neurodegenerative Erkrankungen Longitudinal Cognitive Impairment and Dementia Study (DELCODE) cohort, and an extension cohort of 276 cases of the Alzheimer's Disease Neuroimaging Initiative study. Using Bayesian confirmatory factor analysis, we constructed latent factors for synaptic integrity, microglia, cerebrovascular endothelial function, cytokine/chemokine, and complement components of the inflammatory response using a set of inflammatory markers in cerebrospinal fluid. RESULTS We found strong evidence for an association of synaptic integrity, microglia response, and cerebrovascular endothelial function with a latent factor of AD pathology and with rates of cognitive decline. We found evidence against an association of complement and cytokine/chemokine factors with AD pathology and rates of cognitive decline. DISCUSSION Latent factors provided access to directly unobservable components of the neuroinflammatory response and their association with AD pathology and cognitive decline.
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Dejanovic B, Sheng M, Hanson JE. Targeting synapse function and loss for treatment of neurodegenerative diseases. Nat Rev Drug Discov 2024; 23:23-42. [PMID: 38012296 DOI: 10.1038/s41573-023-00823-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/06/2023] [Indexed: 11/29/2023]
Abstract
Synapse dysfunction and loss are hallmarks of neurodegenerative diseases that correlate with cognitive decline. However, the mechanisms and therapeutic strategies to prevent or reverse synaptic damage remain elusive. In this Review, we discuss recent advances in understanding the molecular and cellular pathways that impair synapses in neurodegenerative diseases, including the effects of protein aggregation and neuroinflammation. We also highlight emerging therapeutic approaches that aim to restore synaptic function and integrity, such as enhancing synaptic plasticity, preventing synaptotoxicity, modulating neuronal network activity and targeting immune signalling. We discuss the preclinical and clinical evidence for each strategy, as well as the challenges and opportunities for developing effective synapse-targeting therapeutics for neurodegenerative diseases.
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Affiliation(s)
| | - Morgan Sheng
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Jesse E Hanson
- Department of Neuroscience, Genentech, South San Francisco, CA, USA.
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Zegarra-Valdivia JA, Pignatelli J, Nuñez A, Torres Aleman I. The Role of Insulin-like Growth Factor I in Mechanisms of Resilience and Vulnerability to Sporadic Alzheimer's Disease. Int J Mol Sci 2023; 24:16440. [PMID: 38003628 PMCID: PMC10671249 DOI: 10.3390/ijms242216440] [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: 10/11/2023] [Revised: 11/06/2023] [Accepted: 11/14/2023] [Indexed: 11/26/2023] Open
Abstract
Despite decades of intense research, disease-modifying therapeutic approaches for Alzheimer's disease (AD) are still very much needed. Apart from the extensively analyzed tau and amyloid pathological cascades, two promising avenues of research that may eventually identify new druggable targets for AD are based on a better understanding of the mechanisms of resilience and vulnerability to this condition. We argue that insulin-like growth factor I (IGF-I) activity in the brain provides a common substrate for the mechanisms of resilience and vulnerability to AD. We postulate that preserved brain IGF-I activity contributes to resilience to AD pathology as this growth factor intervenes in all the major pathological cascades considered to be involved in AD, including metabolic impairment, altered proteostasis, and inflammation, to name the three that are considered to be the most important ones. Conversely, disturbed IGF-I activity is found in many AD risk factors, such as old age, type 2 diabetes, imbalanced diet, sedentary life, sociality, stroke, stress, and low education, whereas the Apolipoprotein (Apo) E4 genotype and traumatic brain injury may also be influenced by brain IGF-I activity. Accordingly, IGF-I activity should be taken into consideration when analyzing these processes, while its preservation will predictably help prevent the progress of AD pathology. Thus, we need to define IGF-I activity in all these conditions and develop a means to preserve it. However, defining brain IGF-I activity cannot be solely based on humoral or tissue levels of this neurotrophic factor, and new functionally based assessments need to be developed.
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Affiliation(s)
- Jonathan A. Zegarra-Valdivia
- Achucarro Basque Center for Neuroscience, 48940 Leioa, Spain;
- Biomedical Research Networking Center on Neurodegenerative Diseases (CIBERNED), 28029 Madrid, Spain;
- School of Medicine, Universidad Señor de Sipán, Chiclayo 14000, Peru
| | - Jaime Pignatelli
- Biomedical Research Networking Center on Neurodegenerative Diseases (CIBERNED), 28029 Madrid, Spain;
- Cajal Institute (CSIC), 28002 Madrid, Spain
| | - Angel Nuñez
- Department of Anatomy, Histology and Neuroscience, Universidad Autónoma de Madrid, 28049 Madrid, Spain;
| | - Ignacio Torres Aleman
- Achucarro Basque Center for Neuroscience, 48940 Leioa, Spain;
- Biomedical Research Networking Center on Neurodegenerative Diseases (CIBERNED), 28029 Madrid, Spain;
- Ikerbasque, Basque Foundation for Science, 48009 Bilbao, Spain
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17
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Jiang J, Zou Y, Xie C, Yang M, Tong Q, Yuan M, Pei X, Deng S, Tian M, Xiao L, Gong Y. Oxytocin alleviates cognitive and memory impairments by decreasing hippocampal microglial activation and synaptic defects via OXTR/ERK/STAT3 pathway in a mouse model of sepsis-associated encephalopathy. Brain Behav Immun 2023; 114:195-213. [PMID: 37648002 DOI: 10.1016/j.bbi.2023.08.023] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 08/09/2023] [Accepted: 08/26/2023] [Indexed: 09/01/2023] Open
Abstract
BACKGROUND Sepsis-associated encephalopathy (SAE) is a diffuse brain dysfunction, characterized by cognitive and memory impairments closely linked to hippocampal dysfunction. Though it is well-known that SAE is a diffuse brain dysfunction with microglial activation, the pathological mechanisms of SAE are not well established and effective clinical interventions are lacking. Oxytocin (OXT) is reported to have anti-inflammatory and neuroprotective roles. However, the effects of OXT on SAE and the underlying mechanisms are not clear. METHODS SAE was induced in adult C57BL/6J male mice by cecal ligation and perforation (CLP) surgery. Exogenous OXT was intranasally applied after surgery. Clinical score, survivor rate, cognitive and memory behaviors, and hippocampal neuronal and non-neuronal functions were evaluated. Cultured microglia challenged with lipopolysaccharide (LPS) were used to investigate the effects of OXT on microglial functions, including inflammatory cytokines release and phagocytosis. The possible intracellular signal pathways involved in the OXT-induced neuroprotection were explored with RNA sequencing. RESULTS Hippocampal OXT level decreases, while the expression of OXT receptor (OXTR) increases around 24 h after CLP surgery. Intranasal OXT application at a proper dose increases mouse survival rate, alleviates cognitive and memory dysfunction, and restores hippocampal synaptic function and neuronal activity via OXTR in the SAE model. Intraperitoneal or local administration of the OXTR antagonist L-368,899 in hippocampal CA1 region inhibited the protective effects of OXT. Moreover, during the early stages of sepsis, hippocampal microglia are activated, while OXT application reduces microglial phagocytosis and the release of inflammatory cytokines, thereby exerting a neuroprotective effect. OXT may improve the SAE outcomes via the OXTR-ERK-STAT3 signaling pathway. CONCLUSION Our study uncovers the dysfunction of the OXT signal in SAE and shows that intranasal OXT application at a proper dose can alleviate SAE outcomes by reducing microglial overactivation, suggests that OXT may be a promising therapeutic approach in managing SAE patients.
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Affiliation(s)
- Junliang Jiang
- Department of Critical Care Medicine and Neurosurgery of Huashan Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China; Department of Orthopedics & Traumatology, Affiliated Hospital of Yunnan University, Yunnan University, Kunming, China
| | - Yue Zou
- Yunnan Eye Institute & Key Laboratory of Yunnan Province, Yunnan Eye Disease Clinical Medical Center, Affiliated Hospital of Yunnan University, Yunnan University, Kunming, China
| | - Chuantong Xie
- Department of Critical Care Medicine and Neurosurgery of Huashan Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
| | - Miaoxian Yang
- Department of Critical Care Medicine and Neurosurgery of Huashan Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
| | - Qiuping Tong
- Department of Critical Care Medicine and Neurosurgery of Huashan Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
| | - Mimi Yuan
- Department of Critical Care Medicine and Neurosurgery of Huashan Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
| | - Xu Pei
- Department of Critical Care Medicine and Neurosurgery of Huashan Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
| | - Shuixiang Deng
- Department of Critical Care Medicine and Neurosurgery of Huashan Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
| | - Mi Tian
- Department of Critical Care Medicine and Neurosurgery of Huashan Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
| | - Lei Xiao
- Department of Critical Care Medicine and Neurosurgery of Huashan Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China.
| | - Ye Gong
- Department of Critical Care Medicine and Neurosurgery of Huashan Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China.
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18
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Gao C, Jiang J, Tan Y, Chen S. Microglia in neurodegenerative diseases: mechanism and potential therapeutic targets. Signal Transduct Target Ther 2023; 8:359. [PMID: 37735487 PMCID: PMC10514343 DOI: 10.1038/s41392-023-01588-0] [Citation(s) in RCA: 70] [Impact Index Per Article: 70.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 07/11/2023] [Accepted: 08/03/2023] [Indexed: 09/23/2023] Open
Abstract
Microglia activation is observed in various neurodegenerative diseases. Recent advances in single-cell technologies have revealed that these reactive microglia were with high spatial and temporal heterogeneity. Some identified microglia in specific states correlate with pathological hallmarks and are associated with specific functions. Microglia both exert protective function by phagocytosing and clearing pathological protein aggregates and play detrimental roles due to excessive uptake of protein aggregates, which would lead to microglial phagocytic ability impairment, neuroinflammation, and eventually neurodegeneration. In addition, peripheral immune cells infiltration shapes microglia into a pro-inflammatory phenotype and accelerates disease progression. Microglia also act as a mobile vehicle to propagate protein aggregates. Extracellular vesicles released from microglia and autophagy impairment in microglia all contribute to pathological progression and neurodegeneration. Thus, enhancing microglial phagocytosis, reducing microglial-mediated neuroinflammation, inhibiting microglial exosome synthesis and secretion, and promoting microglial conversion into a protective phenotype are considered to be promising strategies for the therapy of neurodegenerative diseases. Here we comprehensively review the biology of microglia and the roles of microglia in neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease, multiple system atrophy, amyotrophic lateral sclerosis, frontotemporal dementia, progressive supranuclear palsy, corticobasal degeneration, dementia with Lewy bodies and Huntington's disease. We also summarize the possible microglia-targeted interventions and treatments against neurodegenerative diseases with preclinical and clinical evidence in cell experiments, animal studies, and clinical trials.
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Affiliation(s)
- Chao Gao
- Department of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 200025, Shanghai, China
| | - Jingwen Jiang
- Department of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 200025, Shanghai, China
| | - Yuyan Tan
- Department of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 200025, Shanghai, China.
| | - Shengdi Chen
- Department of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 200025, Shanghai, China.
- Lab for Translational Research of Neurodegenerative Diseases, Shanghai Institute for Advanced Immunochemical Studies (SIAIS), Shanghai Tech University, 201210, Shanghai, China.
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19
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Tzioras M, Daniels MJD, Davies C, Baxter P, King D, McKay S, Varga B, Popovic K, Hernandez M, Stevenson AJ, Barrington J, Drinkwater E, Borella J, Holloway RK, Tulloch J, Moss J, Latta C, Kandasamy J, Sokol D, Smith C, Miron VE, Káradóttir RT, Hardingham GE, Henstridge CM, Brennan PM, McColl BW, Spires-Jones TL. Human astrocytes and microglia show augmented ingestion of synapses in Alzheimer's disease via MFG-E8. Cell Rep Med 2023; 4:101175. [PMID: 37652017 PMCID: PMC10518633 DOI: 10.1016/j.xcrm.2023.101175] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 01/30/2023] [Accepted: 08/07/2023] [Indexed: 09/02/2023]
Abstract
Synapse loss correlates with cognitive decline in Alzheimer's disease (AD). Data from mouse models suggests microglia are important for synapse degeneration, but direct human evidence for any glial involvement in synapse removal in human AD remains to be established. Here we observe astrocytes and microglia from human brains contain greater amounts of synaptic protein in AD compared with non-disease controls, and that proximity to amyloid-β plaques and the APOE4 risk gene exacerbate this effect. In culture, mouse and human astrocytes and primary mouse and human microglia phagocytose AD patient-derived synapses more than synapses from controls. Inhibiting interactions of MFG-E8 rescues the elevated engulfment of AD synapses by astrocytes and microglia without affecting control synapse uptake. Thus, AD promotes increased synapse ingestion by human glial cells at least in part via an MFG-E8 opsonophagocytic mechanism with potential for targeted therapeutic manipulation.
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Affiliation(s)
- Makis Tzioras
- UK Dementia Research Institute, the University of Edinburgh, Edinburgh EH8 9JZ, UK; Centre for Discovery Brain Sciences, the University of Edinburgh, Edinburgh EH8 9JZ, UK
| | - Michael J D Daniels
- UK Dementia Research Institute, the University of Edinburgh, Edinburgh EH8 9JZ, UK; Centre for Discovery Brain Sciences, the University of Edinburgh, Edinburgh EH8 9JZ, UK
| | - Caitlin Davies
- UK Dementia Research Institute, the University of Edinburgh, Edinburgh EH8 9JZ, UK; Centre for Discovery Brain Sciences, the University of Edinburgh, Edinburgh EH8 9JZ, UK
| | - Paul Baxter
- UK Dementia Research Institute, the University of Edinburgh, Edinburgh EH8 9JZ, UK; Centre for Discovery Brain Sciences, the University of Edinburgh, Edinburgh EH8 9JZ, UK
| | - Declan King
- UK Dementia Research Institute, the University of Edinburgh, Edinburgh EH8 9JZ, UK; Centre for Discovery Brain Sciences, the University of Edinburgh, Edinburgh EH8 9JZ, UK
| | - Sean McKay
- UK Dementia Research Institute, the University of Edinburgh, Edinburgh EH8 9JZ, UK; Centre for Discovery Brain Sciences, the University of Edinburgh, Edinburgh EH8 9JZ, UK
| | - Balazs Varga
- Wellcome - MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge CB2 0AW, UK
| | - Karla Popovic
- UK Dementia Research Institute, the University of Edinburgh, Edinburgh EH8 9JZ, UK; Centre for Discovery Brain Sciences, the University of Edinburgh, Edinburgh EH8 9JZ, UK
| | - Madison Hernandez
- UK Dementia Research Institute, the University of Edinburgh, Edinburgh EH8 9JZ, UK; Centre for Discovery Brain Sciences, the University of Edinburgh, Edinburgh EH8 9JZ, UK
| | - Anna J Stevenson
- UK Dementia Research Institute, the University of Edinburgh, Edinburgh EH8 9JZ, UK; Centre for Discovery Brain Sciences, the University of Edinburgh, Edinburgh EH8 9JZ, UK
| | - Jack Barrington
- UK Dementia Research Institute, the University of Edinburgh, Edinburgh EH8 9JZ, UK; Centre for Discovery Brain Sciences, the University of Edinburgh, Edinburgh EH8 9JZ, UK
| | - Elizabeth Drinkwater
- UK Dementia Research Institute, the University of Edinburgh, Edinburgh EH8 9JZ, UK; Centre for Discovery Brain Sciences, the University of Edinburgh, Edinburgh EH8 9JZ, UK
| | - Julia Borella
- UK Dementia Research Institute, the University of Edinburgh, Edinburgh EH8 9JZ, UK; Centre for Discovery Brain Sciences, the University of Edinburgh, Edinburgh EH8 9JZ, UK
| | - Rebecca K Holloway
- MRC Centre for Reproductive Health, the University of Edinburgh, Edinburgh EH16 4TJ, UK
| | - Jane Tulloch
- UK Dementia Research Institute, the University of Edinburgh, Edinburgh EH8 9JZ, UK; Centre for Discovery Brain Sciences, the University of Edinburgh, Edinburgh EH8 9JZ, UK
| | - Jonathan Moss
- MRC Centre for Reproductive Health, the University of Edinburgh, Edinburgh EH16 4TJ, UK; The Roslin Institute, the Royal (Dick) School of Veterinary Studies, the University of Edinburgh, Edinburgh EH25 9RG, UK
| | - Clare Latta
- UK Dementia Research Institute, the University of Edinburgh, Edinburgh EH8 9JZ, UK; Centre for Discovery Brain Sciences, the University of Edinburgh, Edinburgh EH8 9JZ, UK
| | - Jothy Kandasamy
- Department of Clinical Neurosciences, Royal Infirmary of Edinburgh, Edinburgh EH16 4SA, UK
| | - Drahoslav Sokol
- Department of Clinical Neurosciences, Royal Infirmary of Edinburgh, Edinburgh EH16 4SA, UK
| | - Colin Smith
- Centre for Clinical Brain Sciences, the University of Edinburgh, Edinburgh EH16 4SB, UK
| | - Veronique E Miron
- UK Dementia Research Institute, the University of Edinburgh, Edinburgh EH8 9JZ, UK; MRC Centre for Reproductive Health, the University of Edinburgh, Edinburgh EH16 4TJ, UK; Barlo Multiple Sclerosis Centre at St. Michael's Hospital, Keenan Research Centre for Biomedical Science, Toronto, ON M5B 1T8, Canada
| | | | - Giles E Hardingham
- UK Dementia Research Institute, the University of Edinburgh, Edinburgh EH8 9JZ, UK; Centre for Discovery Brain Sciences, the University of Edinburgh, Edinburgh EH8 9JZ, UK
| | | | - Paul M Brennan
- Department of Clinical Neurosciences, Royal Infirmary of Edinburgh, Edinburgh EH16 4SA, UK; Centre for Clinical Brain Sciences, the University of Edinburgh, Edinburgh EH16 4SB, UK
| | - Barry W McColl
- UK Dementia Research Institute, the University of Edinburgh, Edinburgh EH8 9JZ, UK; Centre for Discovery Brain Sciences, the University of Edinburgh, Edinburgh EH8 9JZ, UK.
| | - Tara L Spires-Jones
- UK Dementia Research Institute, the University of Edinburgh, Edinburgh EH8 9JZ, UK; Centre for Discovery Brain Sciences, the University of Edinburgh, Edinburgh EH8 9JZ, UK.
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20
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Jury-Garfe N, You Y, Martínez P, Redding-Ochoa J, Karahan H, Johnson TS, Zhang J, Kim J, Troncoso JC, Lasagna-Reeves CA. Enhanced microglial dynamics and paucity of tau seeding in the amyloid plaque microenvironment contributes to cognitive resilience in Alzheimer's disease. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.27.550884. [PMID: 37546928 PMCID: PMC10402121 DOI: 10.1101/2023.07.27.550884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
Asymptomatic Alzheimer's disease (AsymAD) describes the status of subjects with preserved cognition but with identifiable Alzheimer's disease (AD) brain pathology (i.e. Aβ-amyloid deposits, neuritic plaques, and neurofibrillary tangles) at autopsy. In this study, we investigated the postmortem brains of a cohort of AsymAD cases to gain insight into the underlying mechanisms of resilience to AD pathology and cognitive decline. Our results showed that AsymAD cases exhibit an enrichment of core plaques and decreased filamentous plaque accumulation, as well as an increase in microglia surrounding this last type. In AsymAD cases we found less pathological tau aggregation in dystrophic neurites compared to AD and tau seeding activity comparable to healthy control subjects. We used spatial transcriptomics to further characterize the plaque niche and found autophagy, endocytosis, and phagocytosis within the top upregulated pathways in the AsymAD plaque niche, but not in AD. Furthermore, we found ARP2, an actin-based motility protein crucial to initiate the formation of new actin filaments, increased within microglia in the proximity of amyloid plaques in AsymAD. Our findings support that the amyloid-plaque microenvironment in AsymAD cases is characterized by microglia with highly efficient actin-based cell motility mechanisms and decreased tau seeding compared to AD. These two mechanisms can potentially provide protection against the toxic cascade initiated by Aβ that preserves brain health and slows down the progression of AD pathology.
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Affiliation(s)
- Nur Jury-Garfe
- Stark Neuroscience Research Institute, Indiana University, Indianapolis, USA
- Department of Anatomy, Cell Biology & Physiology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Yanwen You
- Stark Neuroscience Research Institute, Indiana University, Indianapolis, USA
- Department of Anatomy, Cell Biology & Physiology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Pablo Martínez
- Stark Neuroscience Research Institute, Indiana University, Indianapolis, USA
- Department of Anatomy, Cell Biology & Physiology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Javier Redding-Ochoa
- Departments of Pathology, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Hande Karahan
- Stark Neuroscience Research Institute, Indiana University, Indianapolis, USA
- Department of Medical & Molecular Genetics, Indiana University School of Medicine, Indianapolis, USA
| | - Travis S. Johnson
- Department of Biostatistics and Health Data Science, Indiana University School of Medicine, Indianapolis, USA
| | - Jie Zhang
- Department of Medical & Molecular Genetics, Indiana University School of Medicine, Indianapolis, USA
- Center for Computational Biology and Bioinformatics, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Jungsu Kim
- Stark Neuroscience Research Institute, Indiana University, Indianapolis, USA
- Department of Medical & Molecular Genetics, Indiana University School of Medicine, Indianapolis, USA
| | - Juan C. Troncoso
- Departments of Pathology, Johns Hopkins University School of Medicine, Baltimore, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Cristian A. Lasagna-Reeves
- Stark Neuroscience Research Institute, Indiana University, Indianapolis, USA
- Department of Anatomy, Cell Biology & Physiology, Indiana University School of Medicine, Indianapolis, IN, USA
- Center for Computational Biology and Bioinformatics, Indiana University School of Medicine, Indianapolis, IN, USA
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21
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Wood PL. Failure of current Alzheimer's disease hypotheses. Aging (Albany NY) 2023; 15:5959-5960. [PMID: 37393106 PMCID: PMC10373964 DOI: 10.18632/aging.204880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Accepted: 03/29/2023] [Indexed: 07/03/2023]
Affiliation(s)
- Paul L Wood
- Metabolomics Unit, College of Veterinary Medicine, Lincoln Memorial University, Harrogate, TN 37752, USA
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22
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Xu J, Wei H, You P, Sui J, Xiu J, Zhu W, Xu Q. Non-neutralizing antibodies to SARS-Cov-2-related linear epitopes induce psychotic-like behavior in mice. Front Mol Neurosci 2023; 16:1177961. [PMID: 37138704 PMCID: PMC10149951 DOI: 10.3389/fnmol.2023.1177961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Accepted: 03/29/2023] [Indexed: 05/05/2023] Open
Abstract
Objective An increasing number of studies have reported that numerous patients with coronavirus disease 2019 (COVID-19) and vaccinated individuals have developed central nervous system (CNS) symptoms, and that most of the antibodies in their sera have no virus-neutralizing ability. We tested the hypothesis that non-neutralizing anti-S1-111 IgG induced by the spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) could negatively affect the CNS. Methods After 14-day acclimation, the grouped ApoE-/- mice were immunized four times (day 0, day 7, day 14, day 28) with different spike-protein-derived peptides (coupled with KLH) or KLH via subcutaneous injection. Antibody level, state of glial cells, gene expression, prepulse inhibition, locomotor activity, and spatial working memory were assessed from day 21. Results An increased level of anti-S1-111 IgG was measured in their sera and brain homogenate after the immunization. Crucially, anti-S1-111 IgG increased the density of microglia, activated microglia, and astrocytes in the hippocampus, and we observed a psychomotor-like behavioral phenotype with defective sensorimotor gating and impaired spontaneity among S1-111-immunized mice. Transcriptome profiling showed that up-regulated genes in S1-111-immunized mice were mainly associated with synaptic plasticity and mental disorders. Discussion Our results show that the non-neutralizing antibody anti-S1-111 IgG induced by the spike protein caused a series of psychotic-like changes in model mice by activating glial cells and modulating synaptic plasticity. Preventing the production of anti-S1-111 IgG (or other non-neutralizing antibodies) may be a potential strategy to reduce CNS manifestations in COVID-19 patients and vaccinated individuals.
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Affiliation(s)
- Jinming Xu
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, China
- Neuroscience Center, Chinese Academy of Medical Sciences, Beijing, China
| | - Hui Wei
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, China
- Neuroscience Center, Chinese Academy of Medical Sciences, Beijing, China
| | - Pengsheng You
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, China
- Neuroscience Center, Chinese Academy of Medical Sciences, Beijing, China
| | - Jiaping Sui
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, China
- Neuroscience Center, Chinese Academy of Medical Sciences, Beijing, China
| | - Jianbo Xiu
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, China
- Neuroscience Center, Chinese Academy of Medical Sciences, Beijing, China
| | - Wanwan Zhu
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, China
- Neuroscience Center, Chinese Academy of Medical Sciences, Beijing, China
| | - Qi Xu
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Beijing, China
- Neuroscience Center, Chinese Academy of Medical Sciences, Beijing, China
- *Correspondence: Qi Xu,
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23
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Zhang Z, Li Y, Shi J, Zhu L, Dai Y, Fu P, Liu S, Hong M, Zhang J, Wang J, Jiang C. Lymphocyte-Related Immunomodulatory Therapy with Siponimod (BAF-312) Improves Outcomes in Mice with Acute Intracerebral Hemorrhage. Aging Dis 2022; 14:966-991. [PMID: 37191423 DOI: 10.14336/ad.2022.1102] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Accepted: 11/02/2022] [Indexed: 11/18/2022] Open
Abstract
Modulators of the sphingosine-1-phosphate receptor (S1PR) have been proposed as a promising strategy for treating stroke. However, the detailed mechanisms and the potential translational value of S1PR modulators for intracerebral hemorrhage (ICH) therapy warrant exploration. Using collagenase VII-S-induced ICH in the left striatum of mice, we investigated the effects of siponimod on cellular and molecular immunoinflammatory responses in the hemorrhagic brain in the presence or absence of anti-CD3 monoclonal antibodies (Abs). We also assessed the severity of short- and long-term brain injury and evaluated the efficacy of siponimod in long-term neurologic function. Siponimod treatment significantly decreased brain lesion volume and brain water content on day 3 and the volume of the residual lesion and brain atrophy on day 28. It also inhibited neuronal degeneration on day 3 and improved long-term neurologic function. These protective effects may be associated with a reduction in the expression of lymphotactin (XCL1) and T-helper 1 (Th1)-type cytokines (interleukin 1β and interferon-γ). It may also be associated with inhibition of neutrophil and lymphocyte infiltration and alleviation of T lymphocyte activation in perihematomal tissues on day 3. However, siponimod did not affect the infiltration of natural killer cells (NK) or the activation of CD3-negative immunocytes in perihematomal tissues. Furthermore, it did not influence the activation or proliferation of microglia or astrocytes around the hematoma on day 3. Siponimod appears to have a profound impact on infiltration and activation of T lymphocytes after ICH. The effects of neutralized anti-CD3 Abs-induced T-lymphocyte tolerance on siponimod immunomodulation further confirmed that siponimod alleviated the cellular and molecular Th1 response in the hemorrhagic brain. This study provides preclinical evidence that encourages future investigation of immunomodulators, including siponimod, which target the lymphocyte-related immunoinflammatory reaction in ICH therapy.
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