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Liang J, Menon A, Tomco T, Bhattarai N, Smith IN, Khrestian M, Formica SV, Eng C, Buck M, Bekris LM. A Computational Approach in the Systematic Search of the Interaction Partners of Alternatively Spliced TREM2 Isoforms. Int J Mol Sci 2024; 25:9667. [PMID: 39273614 PMCID: PMC11395018 DOI: 10.3390/ijms25179667] [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: 08/05/2024] [Revised: 08/30/2024] [Accepted: 09/02/2024] [Indexed: 09/15/2024] Open
Abstract
Alzheimer's disease is the most common form of dementia, characterized by the pathological accumulation of amyloid-beta (Aβ) plaques and tau neurofibrillary tangles. Triggering receptor expressed on myeloid cells 2 (TREM2) is increasingly recognized as playing a central role in Aβ clearance and microglia activation in AD. The TREM2 gene transcriptional product is alternatively spliced to produce three different protein isoforms. The canonical TREM2 isoform binds to DAP12 to activate downstream pathways. However, little is known about the function or interaction partners of the alternative TREM2 isoforms. The present study utilized a computational approach in a systematic search for new interaction partners of the TREM2 isoforms by integrating several state-of-the-art structural bioinformatics tools from initial large-scale screening to one-on-one corroborative modeling and eventual all-atom visualization. CD9, a cell surface glycoprotein involved in cell-cell adhesion and migration, was identified as a new interaction partner for two TREM2 isoforms, and CALM, a calcium-binding protein involved in calcium signaling, was identified as an interaction partner for a third TREM2 isoform, highlighting the potential role of cell adhesion and calcium regulation in AD.
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Affiliation(s)
- Junyi Liang
- Genomic Medicine Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Aditya Menon
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Taylor Tomco
- Genomic Medicine Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Nisha Bhattarai
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Iris Nira Smith
- Genomic Medicine Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Maria Khrestian
- Genomic Medicine Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Shane V Formica
- Genomic Medicine Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Charis Eng
- Genomic Medicine Institute, Cleveland Clinic, Cleveland, OH 44195, USA
- Cleveland Clinic Lerner College of Medicine, Cleveland, OH 44195, USA
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Matthias Buck
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Lynn M Bekris
- Genomic Medicine Institute, Cleveland Clinic, Cleveland, OH 44195, USA
- Cleveland Clinic Lerner College of Medicine, Cleveland, OH 44195, USA
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA
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Zhang J, Zhang Y, Wang J, Xia Y, Zhang J, Chen L. Recent advances in Alzheimer's disease: Mechanisms, clinical trials and new drug development strategies. Signal Transduct Target Ther 2024; 9:211. [PMID: 39174535 PMCID: PMC11344989 DOI: 10.1038/s41392-024-01911-3] [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: 11/09/2023] [Revised: 03/18/2024] [Accepted: 07/02/2024] [Indexed: 08/24/2024] Open
Abstract
Alzheimer's disease (AD) stands as the predominant form of dementia, presenting significant and escalating global challenges. Its etiology is intricate and diverse, stemming from a combination of factors such as aging, genetics, and environment. Our current understanding of AD pathologies involves various hypotheses, such as the cholinergic, amyloid, tau protein, inflammatory, oxidative stress, metal ion, glutamate excitotoxicity, microbiota-gut-brain axis, and abnormal autophagy. Nonetheless, unraveling the interplay among these pathological aspects and pinpointing the primary initiators of AD require further elucidation and validation. In the past decades, most clinical drugs have been discontinued due to limited effectiveness or adverse effects. Presently, available drugs primarily offer symptomatic relief and often accompanied by undesirable side effects. However, recent approvals of aducanumab (1) and lecanemab (2) by the Food and Drug Administration (FDA) present the potential in disrease-modifying effects. Nevertheless, the long-term efficacy and safety of these drugs need further validation. Consequently, the quest for safer and more effective AD drugs persists as a formidable and pressing task. This review discusses the current understanding of AD pathogenesis, advances in diagnostic biomarkers, the latest updates of clinical trials, and emerging technologies for AD drug development. We highlight recent progress in the discovery of selective inhibitors, dual-target inhibitors, allosteric modulators, covalent inhibitors, proteolysis-targeting chimeras (PROTACs), and protein-protein interaction (PPI) modulators. Our goal is to provide insights into the prospective development and clinical application of novel AD drugs.
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Affiliation(s)
- Jifa Zhang
- Department of Neurology, Laboratory of Neuro-system and Multimorbidity and State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Yinglu Zhang
- Department of Neurology, Laboratory of Neuro-system and Multimorbidity and State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Jiaxing Wang
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, 38163, TN, USA
| | - Yilin Xia
- Department of Neurology, Laboratory of Neuro-system and Multimorbidity and State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Jiaxian Zhang
- Department of Neurology, Laboratory of Neuro-system and Multimorbidity and State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Lei Chen
- Department of Neurology, Laboratory of Neuro-system and Multimorbidity and State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan, China.
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Levites Y, Dammer EB, Ran Y, Tsering W, Duong D, Abreha M, Gadhavi J, Lolo K, Trejo-Lopez J, Phillips J, Iturbe A, Erquizi A, Moore BD, Ryu D, Natu A, Dillon K, Torrellas J, Moran C, Ladd T, Afroz F, Islam T, Jagirdar J, Funk CC, Robinson M, Rangaraju S, Borchelt DR, Ertekin-Taner N, Kelly JW, Heppner FL, Johnson ECB, McFarland K, Levey AI, Prokop S, Seyfried NT, Golde TE. Integrative proteomics identifies a conserved Aβ amyloid responsome, novel plaque proteins, and pathology modifiers in Alzheimer's disease. Cell Rep Med 2024; 5:101669. [PMID: 39127040 PMCID: PMC11384960 DOI: 10.1016/j.xcrm.2024.101669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 04/15/2024] [Accepted: 07/10/2024] [Indexed: 08/12/2024]
Abstract
Alzheimer's disease (AD) is a complex neurodegenerative disorder that develops over decades. AD brain proteomics reveals vast alterations in protein levels and numerous altered biologic pathways. Here, we compare AD brain proteome and network changes with the brain proteomes of amyloid β (Aβ)-depositing mice to identify conserved and divergent protein networks with the conserved networks identifying an Aβ amyloid responsome. Proteins in the most conserved network (M42) accumulate in plaques, cerebrovascular amyloid (CAA), and/or dystrophic neuronal processes, and overexpression of two M42 proteins, midkine (Mdk) and pleiotrophin (PTN), increases the accumulation of Aβ in plaques and CAA. M42 proteins bind amyloid fibrils in vitro, and MDK and PTN co-accumulate with cardiac transthyretin amyloid. M42 proteins appear intimately linked to amyloid deposition and can regulate amyloid deposition, suggesting that they are pathology modifiers and thus putative therapeutic targets. We posit that amyloid-scaffolded accumulation of numerous M42+ proteins is a central mechanism mediating downstream pathophysiology in AD.
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Affiliation(s)
- Yona Levites
- Department of Pharmacology and Chemical Biology, School of Medicine, Emory University, Atlanta, GA, USA; Goizueta Brain Health Institute and Alzheimer's Disease Research Center, Emory University School of Medicine, Atlanta, GA, USA; Center for Neurodegenerative Disease Center, Emory University School of Medicine, Atlanta, GA, USA
| | - Eric B Dammer
- Department of Biochemistry, School of Medicine, Emory University, Atlanta, GA, USA; Goizueta Brain Health Institute and Alzheimer's Disease Research Center, Emory University School of Medicine, Atlanta, GA, USA; Center for Neurodegenerative Disease Center, Emory University School of Medicine, Atlanta, GA, USA
| | - Yong Ran
- Department of Pharmacology and Chemical Biology, School of Medicine, Emory University, Atlanta, GA, USA; Goizueta Brain Health Institute and Alzheimer's Disease Research Center, Emory University School of Medicine, Atlanta, GA, USA; Center for Neurodegenerative Disease Center, Emory University School of Medicine, Atlanta, GA, USA
| | - Wangchen Tsering
- Department of Pathology, College of Medicine, University of Florida, Gainesville, FL, USA; Evelyn F. and William L. McKnight Brain Institute, University of Florida, Gainesville, FL, USA; Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, FL, USA
| | - Duc Duong
- Department of Biochemistry, School of Medicine, Emory University, Atlanta, GA, USA; Goizueta Brain Health Institute and Alzheimer's Disease Research Center, Emory University School of Medicine, Atlanta, GA, USA; Center for Neurodegenerative Disease Center, Emory University School of Medicine, Atlanta, GA, USA
| | - Measho Abreha
- Department of Biochemistry, School of Medicine, Emory University, Atlanta, GA, USA; Goizueta Brain Health Institute and Alzheimer's Disease Research Center, Emory University School of Medicine, Atlanta, GA, USA; Center for Neurodegenerative Disease Center, Emory University School of Medicine, Atlanta, GA, USA
| | - Joshna Gadhavi
- Department of Biochemistry, School of Medicine, Emory University, Atlanta, GA, USA; Goizueta Brain Health Institute and Alzheimer's Disease Research Center, Emory University School of Medicine, Atlanta, GA, USA; Center for Neurodegenerative Disease Center, Emory University School of Medicine, Atlanta, GA, USA
| | - Kiara Lolo
- Department of Pathology, College of Medicine, University of Florida, Gainesville, FL, USA; Evelyn F. and William L. McKnight Brain Institute, University of Florida, Gainesville, FL, USA; Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, FL, USA
| | - Jorge Trejo-Lopez
- Department of Pathology, College of Medicine, University of Florida, Gainesville, FL, USA; Evelyn F. and William L. McKnight Brain Institute, University of Florida, Gainesville, FL, USA; Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, FL, USA
| | - Jennifer Phillips
- Department of Pathology, College of Medicine, University of Florida, Gainesville, FL, USA; Evelyn F. and William L. McKnight Brain Institute, University of Florida, Gainesville, FL, USA; Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, FL, USA
| | - Andrea Iturbe
- Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, FL, USA; Department of Neuroscience, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Aya Erquizi
- Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, FL, USA; Department of Neuroscience, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Brenda D Moore
- Department of Pharmacology and Chemical Biology, School of Medicine, Emory University, Atlanta, GA, USA; Goizueta Brain Health Institute and Alzheimer's Disease Research Center, Emory University School of Medicine, Atlanta, GA, USA; Center for Neurodegenerative Disease Center, Emory University School of Medicine, Atlanta, GA, USA
| | - Danny Ryu
- Department of Pharmacology and Chemical Biology, School of Medicine, Emory University, Atlanta, GA, USA; Goizueta Brain Health Institute and Alzheimer's Disease Research Center, Emory University School of Medicine, Atlanta, GA, USA; Center for Neurodegenerative Disease Center, Emory University School of Medicine, Atlanta, GA, USA
| | - Aditya Natu
- Department of Biochemistry, School of Medicine, Emory University, Atlanta, GA, USA; Goizueta Brain Health Institute and Alzheimer's Disease Research Center, Emory University School of Medicine, Atlanta, GA, USA; Center for Neurodegenerative Disease Center, Emory University School of Medicine, Atlanta, GA, USA
| | - Kristy Dillon
- Evelyn F. and William L. McKnight Brain Institute, University of Florida, Gainesville, FL, USA; Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, FL, USA; Department of Neuroscience, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Jose Torrellas
- Evelyn F. and William L. McKnight Brain Institute, University of Florida, Gainesville, FL, USA; Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, FL, USA; Department of Neuroscience, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Corey Moran
- Evelyn F. and William L. McKnight Brain Institute, University of Florida, Gainesville, FL, USA; Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, FL, USA; Department of Neuroscience, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Thomas Ladd
- Evelyn F. and William L. McKnight Brain Institute, University of Florida, Gainesville, FL, USA; Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, FL, USA
| | - Farhana Afroz
- Department of Pharmacology and Chemical Biology, School of Medicine, Emory University, Atlanta, GA, USA; Goizueta Brain Health Institute and Alzheimer's Disease Research Center, Emory University School of Medicine, Atlanta, GA, USA; Center for Neurodegenerative Disease Center, Emory University School of Medicine, Atlanta, GA, USA
| | - Tariful Islam
- Department of Pharmacology and Chemical Biology, School of Medicine, Emory University, Atlanta, GA, USA; Goizueta Brain Health Institute and Alzheimer's Disease Research Center, Emory University School of Medicine, Atlanta, GA, USA; Center for Neurodegenerative Disease Center, Emory University School of Medicine, Atlanta, GA, USA
| | - Jaishree Jagirdar
- Department of Pathology and Laboratory Medicine, Emory University Hospital, Atlanta, GA, USA
| | - Cory C Funk
- Institute for Systems Biology, Seattle, WA, USA
| | | | | | - David R Borchelt
- Evelyn F. and William L. McKnight Brain Institute, University of Florida, Gainesville, FL, USA; Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, FL, USA; Department of Neuroscience, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Nilüfer Ertekin-Taner
- Mayo Clinic, Department of Neuroscience, Jacksonville, FL, USA; Mayo Clinic, Department of Neurology, Jacksonville, FL, USA
| | - Jeffrey W Kelly
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Frank L Heppner
- Department of Neuropathology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 110117 Berlin, Germany; German Center for Neurodegenerative Diseases (DZNE) Berlin, 110117 Berlin, Germany; Cluster of Excellence, NeuroCure, Charitéplatz, 110117 Berlin, Germany
| | - Erik C B Johnson
- Department of Neurology, School of Medicine, Emory University, Atlanta, GA, USA; Goizueta Brain Health Institute and Alzheimer's Disease Research Center, Emory University School of Medicine, Atlanta, GA, USA; Center for Neurodegenerative Disease Center, Emory University School of Medicine, Atlanta, GA, USA
| | - Karen McFarland
- Department of Pharmacology and Chemical Biology, School of Medicine, Emory University, Atlanta, GA, USA; Goizueta Brain Health Institute and Alzheimer's Disease Research Center, Emory University School of Medicine, Atlanta, GA, USA; Center for Neurodegenerative Disease Center, Emory University School of Medicine, Atlanta, GA, USA
| | - Allan I Levey
- Department of Neurology, School of Medicine, Emory University, Atlanta, GA, USA; Goizueta Brain Health Institute and Alzheimer's Disease Research Center, Emory University School of Medicine, Atlanta, GA, USA; Center for Neurodegenerative Disease Center, Emory University School of Medicine, Atlanta, GA, USA
| | - Stefan Prokop
- Department of Pathology, College of Medicine, University of Florida, Gainesville, FL, USA; Evelyn F. and William L. McKnight Brain Institute, University of Florida, Gainesville, FL, USA; Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, FL, USA; Department of Neurology, College of Medicine, University of Florida, Gainesville, FL, USA.
| | - Nicholas T Seyfried
- Department of Biochemistry, School of Medicine, Emory University, Atlanta, GA, USA; Goizueta Brain Health Institute and Alzheimer's Disease Research Center, Emory University School of Medicine, Atlanta, GA, USA; Center for Neurodegenerative Disease Center, Emory University School of Medicine, Atlanta, GA, USA.
| | - Todd E Golde
- Department of Pharmacology and Chemical Biology, School of Medicine, Emory University, Atlanta, GA, USA; Department of Neurology, School of Medicine, Emory University, Atlanta, GA, USA; Goizueta Brain Health Institute and Alzheimer's Disease Research Center, Emory University School of Medicine, Atlanta, GA, USA; Center for Neurodegenerative Disease Center, Emory University School of Medicine, Atlanta, GA, USA.
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Deng Q, Wu C, Parker E, Liu TCY, Duan R, Yang L. Microglia and Astrocytes in Alzheimer's Disease: Significance and Summary of Recent Advances. Aging Dis 2024; 15:1537-1564. [PMID: 37815901 PMCID: PMC11272214 DOI: 10.14336/ad.2023.0907] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Accepted: 09/07/2023] [Indexed: 10/12/2023] Open
Abstract
Alzheimer's disease, one of the most common forms of dementia, is characterized by a slow progression of cognitive impairment and neuronal loss. Currently, approved treatments for AD are hindered by various side effects and limited efficacy. Despite considerable research, practical treatments for AD have not been developed. Increasing evidence shows that glial cells, especially microglia and astrocytes, are essential in the initiation and progression of AD. During AD progression, activated resident microglia increases the ability of resting astrocytes to transform into reactive astrocytes, promoting neurodegeneration. Extensive clinical and molecular studies show the involvement of microglia and astrocyte-mediated neuroinflammation in AD pathology, indicating that microglia and astrocytes may be potential therapeutic targets for AD. This review will summarize the significant and recent advances of microglia and astrocytes in the pathogenesis of AD in three parts. First, we will review the typical pathological changes of AD and discuss microglia and astrocytes in terms of function and phenotypic changes. Second, we will describe microglia and astrocytes' physiological and pathological role in AD. These roles include the inflammatory response, "eat me" and "don't eat me" signals, Aβ seeding, propagation, clearance, synapse loss, synaptic pruning, remyelination, and demyelination. Last, we will review the pharmacological and non-pharmacological therapies targeting microglia and astrocytes in AD. We conclude that microglia and astrocytes are essential in the initiation and development of AD. Therefore, understanding the new role of microglia and astrocytes in AD progression is critical for future AD studies and clinical trials. Moreover, pharmacological, and non-pharmacological therapies targeting microglia and astrocytes, with specific studies investigating microglia and astrocyte-mediated neuronal damage and repair, may be a promising research direction for future studies regarding AD treatment and prevention.
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Affiliation(s)
- Qianting Deng
- Laboratory of Exercise and Neurobiology, School of Physical Education and Sports Science, South China Normal University, Guangzhou 510006, China.
| | - Chongyun Wu
- Laboratory of Exercise and Neurobiology, School of Physical Education and Sports Science, South China Normal University, Guangzhou 510006, China.
- Laboratory of Regenerative Medicine in Sports Science, School of Physical Education and Sports Science, South China Normal University, Guangzhou 510006, China.
| | - Emily Parker
- Medical College of Georgia at Augusta University, Augusta, GA 30912, USA.
| | - Timon Cheng-Yi Liu
- Laboratory of Laser Sports Medicine, School of Physical Education and Sports Science, South China Normal University, Guangzhou 510006, China.
| | - Rui Duan
- Laboratory of Regenerative Medicine in Sports Science, School of Physical Education and Sports Science, South China Normal University, Guangzhou 510006, China.
| | - Luodan Yang
- Laboratory of Exercise and Neurobiology, School of Physical Education and Sports Science, South China Normal University, Guangzhou 510006, China.
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Dean HB, Greer RA, Yang SZ, Elston DS, Brett TJ, Roberson ED, Song Y. Multimerization of TREM2 is impaired by Alzheimer's disease-associated variants. Alzheimers Dement 2024. [PMID: 39032157 DOI: 10.1002/alz.14124] [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: 03/20/2024] [Revised: 06/04/2024] [Accepted: 06/17/2024] [Indexed: 07/22/2024]
Abstract
INTRODUCTION The immune receptor triggering receptor expressed on myeloid cells 2 (TREM2) is among the strongest genetic risk factors for Alzheimer's disease (AD) and is a therapeutic target. TREM2 multimers have been identified in crystallography and implicated in the efficacy of antibody therapeutics; however, the molecular basis for TREM2 multimerization remains poorly understood. METHODS We used molecular dynamics simulations and binding energy analysis to determine the effects of AD-associated variants on TREM2 multimerization and validated with experimental results. RESULTS TREM2 trimers remained stably bound, driven primarily by salt bridge between residues D87 and R76 at the interface of TREM2 units. This salt bridge was disrupted by the AD-associated variants R47H and R98W and nearly ablated by the D87N variant. This decreased binding among TREM2 multimers was validated with co-immunoprecipitation assays. DISCUSSION This study uncovers a molecular basis for TREM2 forming stable trimers and unveils a novel mechanism by which TREM2 variants may increase AD risk by disrupting TREM2 oligomerization to impair TREM2 normal function. HIGHLIGHTS Triggering receptor expressed on myeloid cells 2 (TREM2) multimerization could regulate TREM2 activation and function. D87-R76 salt bridges at the interface of TREM2 units drive the formation of stable TREM2 dimers and trimers. Alzheimer's disease (AD)-associated R47H and R98W variants disrupt the D87-R76 salt bridge. The AD-associated D87N variant leads to complete loss of the D87-R76 salt bridge.
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Affiliation(s)
- Hunter B Dean
- Department of Biomedical Engineering, School of Engineering, University of Alabama at Birmingham, Birmingham, Alabama, USA
- Alzheimer's Disease Center, Center for Neurodegeneration and Experimental Therapeutics, & Departments of Neurology and Neurobiology, Marnix E. Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
- Medical Scientist Training Program, Marnix E. Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Rory A Greer
- Department of Biomedical Engineering, School of Engineering, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Shan-Zhong Yang
- Department of Biomedical Engineering, School of Engineering, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Daniel S Elston
- Alzheimer's Disease Center, Center for Neurodegeneration and Experimental Therapeutics, & Departments of Neurology and Neurobiology, Marnix E. Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Thomas J Brett
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Department of Biochemistry and Molecular Biophysics, Hope Center for Neurological Disorders, & Department of Cell Biology and Physiology, Washington University School of Medicine, Washington University in St Louis, St. Louis, Missouri, USA
| | - Erik D Roberson
- Alzheimer's Disease Center, Center for Neurodegeneration and Experimental Therapeutics, & Departments of Neurology and Neurobiology, Marnix E. Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Yuhua Song
- Department of Biomedical Engineering, School of Engineering, University of Alabama at Birmingham, Birmingham, Alabama, USA
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Etxeberria A, Shen YAA, Vito S, Silverman SM, Imperio J, Lalehzadeh G, Soung AL, Du C, Xie L, Choy MK, Hsiao YC, Ngu H, Cho CH, Ghosh S, Novikova G, Rezzonico MG, Leahey R, Weber M, Gogineni A, Elstrott J, Xiong M, Greene JJ, Stark KL, Chan P, Roth GA, Adrian M, Li Q, Choi M, Wong WR, Sandoval W, Foreman O, Nugent AA, Friedman BA, Sadekar S, Hötzel I, Hansen DV, Chih B, Yuen TJ, Weimer RM, Easton A, Meilandt WJ, Bohlen CJ. Neutral or Detrimental Effects of TREM2 Agonist Antibodies in Preclinical Models of Alzheimer's Disease and Multiple Sclerosis. J Neurosci 2024; 44:e2347232024. [PMID: 38830764 PMCID: PMC11255434 DOI: 10.1523/jneurosci.2347-23.2024] [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: 12/18/2023] [Revised: 05/06/2024] [Accepted: 05/25/2024] [Indexed: 06/05/2024] Open
Abstract
Human genetics and preclinical studies have identified key contributions of TREM2 to several neurodegenerative conditions, inspiring efforts to modulate TREM2 therapeutically. Here, we characterize the activities of three TREM2 agonist antibodies in multiple mixed-sex mouse models of Alzheimer's disease (AD) pathology and remyelination. Receptor activation and downstream signaling are explored in vitro, and active dose ranges are determined in vivo based on pharmacodynamic responses from microglia. For mice bearing amyloid-β (Aβ) pathology (PS2APP) or combined Aβ and tau pathology (TauPS2APP), chronic TREM2 agonist antibody treatment had limited impact on microglia engagement with pathology, overall pathology burden, or downstream neuronal damage. For mice with demyelinating injuries triggered acutely with lysolecithin, TREM2 agonist antibodies unexpectedly disrupted injury resolution. Likewise, TREM2 agonist antibodies limited myelin recovery for mice experiencing chronic demyelination from cuprizone. We highlight the contributions of dose timing and frequency across models. These results introduce important considerations for future TREM2-targeting approaches.
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Affiliation(s)
- Ainhoa Etxeberria
- Departments of Neuroscience, Genentech, Inc., South San Francisco, California 94080
| | - Yun-An A Shen
- Departments of Neuroscience, Genentech, Inc., South San Francisco, California 94080
| | - Stephen Vito
- Departments of Neuroscience, Genentech, Inc., South San Francisco, California 94080
| | - Sean M Silverman
- Departments of Neuroscience, Genentech, Inc., South San Francisco, California 94080
| | - Jose Imperio
- Departments of Neuroscience, Genentech, Inc., South San Francisco, California 94080
| | - Guita Lalehzadeh
- Departments of Neuroscience, Genentech, Inc., South San Francisco, California 94080
| | - Allison L Soung
- Departments of Neuroscience, Genentech, Inc., South San Francisco, California 94080
| | - Changchun Du
- Biochemical and Cellular Pharmacology, Genentech, Inc., South San Francisco, California 94080
| | - Luke Xie
- Translational Imaging, Genentech, Inc., South San Francisco, California 94080
| | - Man Kin Choy
- Translational Imaging, Genentech, Inc., South San Francisco, California 94080
| | - Yi-Chun Hsiao
- Antibody Engineering, Genentech, Inc., South San Francisco, California 94080
| | - Hai Ngu
- Pathology, Genentech, Inc., South San Francisco, California 94080
| | - Chang Hoon Cho
- Human Pathobiology and OMNI Reverse Translation, Genentech, Inc., South San Francisco, California 94080
| | - Soumitra Ghosh
- Departments of Neuroscience, Genentech, Inc., South San Francisco, California 94080
| | - Gloriia Novikova
- Bioinformatics, Genentech, Inc., South San Francisco, California 94080
| | | | - Rebecca Leahey
- Departments of Neuroscience, Genentech, Inc., South San Francisco, California 94080
| | - Martin Weber
- Departments of Neuroscience, Genentech, Inc., South San Francisco, California 94080
| | - Alvin Gogineni
- Translational Imaging, Genentech, Inc., South San Francisco, California 94080
| | - Justin Elstrott
- Translational Imaging, Genentech, Inc., South San Francisco, California 94080
| | - Monica Xiong
- Departments of Neuroscience, Genentech, Inc., South San Francisco, California 94080
| | - Jacob J Greene
- Departments of Neuroscience, Genentech, Inc., South San Francisco, California 94080
| | - Kimberly L Stark
- Departments of Neuroscience, Genentech, Inc., South San Francisco, California 94080
| | - Pamela Chan
- Biochemical and Cellular Pharmacology, Genentech, Inc., South San Francisco, California 94080
| | - Gillie A Roth
- Preclinical and Translational Pharmacokinetics and Pharmacodynamics, Genentech, Inc., South San Francisco, California 94080
| | - Max Adrian
- Pathology, Genentech, Inc., South San Francisco, California 94080
| | - Qingling Li
- Microchemistry Lipidomics and Proteomics, Genentech, Inc., South San Francisco, California 94080
| | - Meena Choi
- Microchemistry Lipidomics and Proteomics, Genentech, Inc., South San Francisco, California 94080
| | - Weng Ruh Wong
- Microchemistry Lipidomics and Proteomics, Genentech, Inc., South San Francisco, California 94080
| | - Wendy Sandoval
- Microchemistry Lipidomics and Proteomics, Genentech, Inc., South San Francisco, California 94080
| | - Oded Foreman
- Pathology, Genentech, Inc., South San Francisco, California 94080
| | - Alicia A Nugent
- Human Pathobiology and OMNI Reverse Translation, Genentech, Inc., South San Francisco, California 94080
| | - Brad A Friedman
- Bioinformatics, Genentech, Inc., South San Francisco, California 94080
| | - Shraddha Sadekar
- Preclinical and Translational Pharmacokinetics and Pharmacodynamics, Genentech, Inc., South San Francisco, California 94080
| | - Isidro Hötzel
- Antibody Engineering, Genentech, Inc., South San Francisco, California 94080
| | - David V Hansen
- Departments of Neuroscience, Genentech, Inc., South San Francisco, California 94080
| | - Ben Chih
- Departments of Neuroscience, Genentech, Inc., South San Francisco, California 94080
- Biochemical and Cellular Pharmacology, Genentech, Inc., South San Francisco, California 94080
| | - Tracy J Yuen
- Departments of Neuroscience, Genentech, Inc., South San Francisco, California 94080
| | - Robby M Weimer
- Translational Imaging, Genentech, Inc., South San Francisco, California 94080
| | - Amy Easton
- Departments of Neuroscience, Genentech, Inc., South San Francisco, California 94080
| | - William J Meilandt
- Departments of Neuroscience, Genentech, Inc., South San Francisco, California 94080
| | - Christopher J Bohlen
- Departments of Neuroscience, Genentech, Inc., South San Francisco, California 94080
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7
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Bharadwaj S, Groza Y, Mierzwicka JM, Malý P. Current understanding on TREM-2 molecular biology and physiopathological functions. Int Immunopharmacol 2024; 134:112042. [PMID: 38703564 DOI: 10.1016/j.intimp.2024.112042] [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: 02/08/2024] [Revised: 04/05/2024] [Accepted: 04/05/2024] [Indexed: 05/06/2024]
Abstract
Triggering receptor expressed on myeloid cells 2 (TREM-2), a glycosylated receptor belonging to the immunoglobin superfamily and especially expressed in the myeloid cell lineage, is frequently explained as a reminiscent receptor for both adaptive and innate immunity regulation. TREM-2 is also acknowledged to influence NK cell differentiation via the PI3K and PLCγ signaling pathways, as well as the partial activation or direct inhibition of T cells. Additionally, TREM-2 overexpression is substantially linked to cell-specific functions, such as enhanced phagocytosis, reduced toll-like receptor (TLR)-mediated inflammatory cytokine production, increased transcription of anti-inflammatory cytokines, and reshaped T cell function. Whereas TREM-2-deficient cells exhibit diminished phagocytic function and enhanced proinflammatory cytokines production, proceeding to inflammatory injuries and an immunosuppressive environment for disease progression. Despite the growing literature supporting TREM-2+ cells in various diseases, such as neurodegenerative disorders and cancer, substantial facets of TREM-2-mediated signaling remain inadequately understood relevant to pathophysiology conditions. In this direction, herein, we have summarized the current knowledge on TREM-2 biology and cell-specific TREM-2 expression, particularly in the modulation of pivotal TREM-2-dependent functions under physiopathological conditions. Furthermore, molecular regulation and generic biological relevance of TREM-2 are also discussed, which might provide an alternative approach for preventing or reducing TREM-2-associated deformities. At last, we discussed the TREM-2 function in supporting an immunosuppressive cancer environment and as a potential drug target for cancer immunotherapy. Hence, summarized knowledge of TREM-2 might provide a window to overcome challenges in clinically effective therapies for TREM-2-induced diseases in humans.
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Affiliation(s)
- Shiv Bharadwaj
- Laboratory of Ligand Engineering, Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV Research Center, Průmyslová 595, 252 50 Vestec, Czech Republic.
| | - Yaroslava Groza
- Laboratory of Ligand Engineering, Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV Research Center, Průmyslová 595, 252 50 Vestec, Czech Republic
| | - Joanna M Mierzwicka
- Laboratory of Ligand Engineering, Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV Research Center, Průmyslová 595, 252 50 Vestec, Czech Republic
| | - Petr Malý
- Laboratory of Ligand Engineering, Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV Research Center, Průmyslová 595, 252 50 Vestec, Czech Republic.
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8
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Yan H, Wang W, Cui T, Shao Y, Li M, Fang L, Feng L. Advances in the Understanding of the Correlation Between Neuroinflammation and Microglia in Alzheimer's Disease. Immunotargets Ther 2024; 13:287-304. [PMID: 38881647 PMCID: PMC11180466 DOI: 10.2147/itt.s455881] [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: 03/14/2024] [Accepted: 06/05/2024] [Indexed: 06/18/2024] Open
Abstract
Alzheimer's disease (AD) is a fatal neurodegenerative disease with a subtle and progressive onset and is the most common type of dementia. However, its etiology and pathogenesis have not yet been fully elucidated. The common pathological manifestations of AD include extraneuronal β-amyloid deposition (Aβ), intraneuronal tau protein phosphorylation leading to the formation of 'neurofibrillary tangles' (NFTs), neuroinflammation, progressive loss of brain neurons/synapses, and glucose metabolism disorders. Current treatment approaches for AD primarily focus on the 'Aβ cascade hypothesis and abnormal aggregation of hyperphosphorylation of tau proteins', but have shown limited efficacy. Therefore, there is an ongoing need to identify more effective treatment targets for AD. The central nervous system (CNS) inflammatory response plays a key role in the occurrence and development of AD. Neuroinflammation is an immune response activated by glial cells in the CNS that usually occurs in response to stimuli such as nerve injury, infection and toxins or in response to autoimmunity. Neuroinflammation ranks as the third most prominent pathological feature in AD, following Aβ and NFTs. In recent years, the focus on the role of neuroinflammation and microglia in AD has increased due to the advancements in genome-wide association studies (GWAS) and sequencing technology. Furthermore, research has validated the pivotal role of microglia-mediated neuroinflammation in the progression of AD. Therefore, this article reviews the latest research progress on the role of neuroinflammation triggered by microglia in AD in recent years, aiming to provide a new theoretical basis for further exploring the role of neuroinflammation in the process of AD occurrence and development.
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Affiliation(s)
- Huiying Yan
- Department of Neurology, The Third Affiliated Clinical Hospital of the Changchun University of Chinese Medicine, Changchun, People's Republic of China
| | - Wei Wang
- Department of Intensive Care Unit, The Affiliated Hospital to Changchun University of Chinese Medicine, Changchun, People's Republic of China
| | - Tingting Cui
- Department of Neurology, The Third Affiliated Clinical Hospital of the Changchun University of Chinese Medicine, Changchun, People's Republic of China
| | - Yanxin Shao
- Department of Neurology, The Second Affiliated Hospital of Shandong First Medical University, Taian, People's Republic of China
| | - Mingquan Li
- Department of Neurology, The Third Affiliated Clinical Hospital of the Changchun University of Chinese Medicine, Changchun, People's Republic of China
| | - Limei Fang
- Department of Neurology, The Third Affiliated Clinical Hospital of the Changchun University of Chinese Medicine, Changchun, People's Republic of China
| | - Lina Feng
- Department of Neurology, The Third Affiliated Clinical Hospital of the Changchun University of Chinese Medicine, Changchun, People's Republic of China
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9
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Lin C, Kong Y, Chen Q, Zeng J, Pan X, Miao J. Decoding sTREM2: its impact on Alzheimer's disease - a comprehensive review of mechanisms and implications. Front Aging Neurosci 2024; 16:1420731. [PMID: 38912524 PMCID: PMC11190086 DOI: 10.3389/fnagi.2024.1420731] [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: 04/21/2024] [Accepted: 05/30/2024] [Indexed: 06/25/2024] Open
Abstract
Soluble Triggering Receptor Expressed on Myeloid Cells 2 (sTREM2) plays a crucial role in the pathogenesis of Alzheimer's disease (AD). This review comprehensively examines sTREM2's involvement in AD, focusing on its regulatory functions in microglial responses, neuroinflammation, and interactions with key pathological processes. We discuss the dynamic changes in sTREM2 levels in cerebrospinal fluid and plasma throughout AD progression, highlighting its potential as a therapeutic target. Furthermore, we explore the impact of genetic variants on sTREM2 expression and its interplay with other AD risk genes. The evidence presented in this review suggests that modulating sTREM2 activity could influence AD trajectory, making it a promising avenue for future research and drug development. By providing a holistic understanding of sTREM2's multifaceted role in AD, this review aims to guide future studies and inspire novel therapeutic strategies.
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Affiliation(s)
- Cui Lin
- Shenzhen Bao’an District Hospital of Traditional Chinese Medicine, Shenzhen, Guangdong, China
| | - Yu Kong
- Shenzhen Bao’an District Hospital of Traditional Chinese Medicine, Shenzhen, Guangdong, China
| | - Qian Chen
- Shenzhen Bao’an District Hospital of Traditional Chinese Medicine, Shenzhen, Guangdong, China
| | - Jixiang Zeng
- Shenzhen Bao’an Traditional Chinese Medicine Hospital, Guangzhou University of Chinese Medicine, Shenzhen, Guangdong, China
| | - Xiaojin Pan
- Shenzhen Bao’an District Hospital of Traditional Chinese Medicine, Shenzhen, Guangdong, China
| | - Jifei Miao
- Shenzhen Bao’an District Hospital of Traditional Chinese Medicine, Shenzhen, Guangdong, China
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Fremuth LE, Hu H, van de Vlekkert D, Annunziata I, Weesner JA, Gomero E, d'Azzo A. Neuraminidase 1 regulates the cellular state of microglia by modulating the sialylation of Trem2. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.20.595036. [PMID: 38826426 PMCID: PMC11142087 DOI: 10.1101/2024.05.20.595036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2024]
Abstract
Neuraminidase 1 (Neu1) cleaves terminal sialic acids from sialoglycoproteins in endolysosomes and at the plasma membrane. As such, Neu1 regulates immune cells, primarily those of the monocytic lineage. Here we examined how Neu1 influences microglia by modulating the sialylation of full-length Trem2 (Trem2-FL), a multifunctional receptor that regulates microglial survival, phagocytosis, and cytokine production. When Neu1 was deficient/downregulated, Trem2-FL remained sialylated, accumulated intracellularly, and was excessively cleaved into a C-terminal fragment (Trem2-CTF) and an extracellular soluble domain (sTrem2), enhancing their signaling capacities. Sialylated Trem2-FL (Sia-Trem2-FL) did not hinder Trem2-FL-DAP12-Syk complex assembly but impaired signal transduction through Syk, ultimately abolishing Trem2-dependent phagocytosis. Concurrently, Trem2-CTF-DAP12 complexes dampened NFκB signaling, while sTrem2 propagated Akt-dependent cell survival and NFAT1-mediated production of TNFα and CCL3. Because Neu1 and Trem2 are implicated in neurodegenerative/neuroinflammatory diseases, including Alzheimer disease (AD) and sialidosis, modulating Neu1 activity represents a therapeutic approach to broadly regulate microglia-mediated neuroinflammation.
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11
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Shi Q, Gutierrez RA, Bhat MA. Microglia, Trem2, and Neurodegeneration. Neuroscientist 2024:10738584241254118. [PMID: 38769824 DOI: 10.1177/10738584241254118] [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: 05/22/2024]
Abstract
Microglia are a specialized type of neuroimmune cells that undergo morphological and molecular changes through multiple signaling pathways in response to pathological protein aggregates, neuronal death, tissue injury, or infections. Microglia express Trem2, which serves as a receptor for a multitude of ligands enhancing their phagocytic activity. Trem2 has emerged as a critical modulator of microglial activity, especially in many neurodegenerative disorders. Human TREM2 mutations are associated with an increased risk of developing Alzheimer disease (AD) and other neurodegenerative diseases. Trem2 plays dual roles in neuroinflammation and more specifically in disease-associated microglia. Most recent developments on the molecular mechanisms of Trem2, emphasizing its role in uptake and clearance of amyloid β (Aβ) aggregates and other tissue debris to help protect and preserve the brain, are encouraging. Although Trem2 normally stimulates defense mechanisms, its dysregulation can intensify inflammation, which poses major therapeutic challenges. Recent therapeutic approaches targeting Trem2 via agonistic antibodies and gene therapy methodologies present possible avenues for reducing the burden of neurodegenerative diseases. This review highlights the promise of Trem2 as a therapeutic target, especially for Aβ-associated AD, and calls for more mechanistic investigations to understand the context-specific role of microglial Trem2 in developing effective therapies against neurodegenerative diseases.
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Affiliation(s)
- Qian Shi
- Department of Cellular and Integrative Physiology, Center for Biomedical Neuroscience, Joe R. and Teresa Lozano Long School of Medicine, University of Texas Health Science Center San Antonio, San Antonio, TX, USA
| | - Raul A Gutierrez
- Department of Cellular and Integrative Physiology, Center for Biomedical Neuroscience, Joe R. and Teresa Lozano Long School of Medicine, University of Texas Health Science Center San Antonio, San Antonio, TX, USA
| | - Manzoor A Bhat
- Department of Cellular and Integrative Physiology, Center for Biomedical Neuroscience, Joe R. and Teresa Lozano Long School of Medicine, University of Texas Health Science Center San Antonio, San Antonio, TX, USA
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12
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Yin T, Yesiltepe M, D'Adamio L. Functional BRI2-TREM2 interactions in microglia: implications for Alzheimer's and related dementias. EMBO Rep 2024; 25:1326-1360. [PMID: 38347225 PMCID: PMC10933458 DOI: 10.1038/s44319-024-00077-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 01/17/2024] [Accepted: 01/19/2024] [Indexed: 03/14/2024] Open
Abstract
ITM2B/BRI2 mutations cause Alzheimer's Disease (AD)-related dementias. We observe heightened ITM2B/BRI2 expression in microglia, a pivotal cell type in AD due to risk-increasing variants in the microglial gene TREM2. Single-cell RNA-sequencing demonstrates a Trem2/Bri2-dependent microglia cluster, underscoring their functional interaction. α-secretase cleaves TREM2 into TREM2-CTF and sTREM2. As BRI2 hinders α-secretase cleavage of the AD-related Aβ-Precursor-Protein, we probed whether BRI2 influences TREM2 processing. Our findings indicate a BRI2-TREM2 interaction that inhibits TREM2 processing in heterologous cells. Recombinant BRI2 and TREM2 proteins demonstrate a direct, cell-free BRI2-TREM2 ectodomain interaction. Constitutive and microglial-specific Itm2b-Knock-out mice, and Itm2b-Knock-out primary microglia provide evidence that Bri2 reduces Trem2 processing, boosts Trem2 mRNA expression, and influences Trem2 protein levels through α-secretase-independent pathways, revealing a multifaceted BRI2-TREM2 functional interaction. Moreover, a mutant Itm2b dementia mouse model exhibits elevated Trem2-CTF and sTrem2, mirroring sTREM2 increases in AD patients. Lastly, Bri2 deletion reduces phagocytosis similarly to a pathogenic TREM2 variant that enhances processing. Given BRI2's role in regulating Aβ-Precursor-Protein and TREM2 functions, it holds promise as a therapeutic target for AD and related dementias.
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Affiliation(s)
- Tao Yin
- Department of Pharmacology, Physiology & Neuroscience New Jersey Medical School, Brain Health Institute, Jacqueline Krieger Klein Center in Alzheimer's Disease and Neurodegeneration Research, Rutgers, The State University of New Jersey, 205 South Orange Ave, Newark, NJ, 07103, USA.
| | - Metin Yesiltepe
- Department of Pharmacology, Physiology & Neuroscience New Jersey Medical School, Brain Health Institute, Jacqueline Krieger Klein Center in Alzheimer's Disease and Neurodegeneration Research, Rutgers, The State University of New Jersey, 205 South Orange Ave, Newark, NJ, 07103, USA
| | - Luciano D'Adamio
- Department of Pharmacology, Physiology & Neuroscience New Jersey Medical School, Brain Health Institute, Jacqueline Krieger Klein Center in Alzheimer's Disease and Neurodegeneration Research, Rutgers, The State University of New Jersey, 205 South Orange Ave, Newark, NJ, 07103, USA.
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13
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Pagnon de la Vega M, Syvänen S, Giedraitis V, Hooley M, Konstantinidis E, Meier SR, Rokka J, Eriksson J, Aguilar X, Spires-Jones TL, Lannfelt L, Nilsson LNG, Erlandsson A, Hultqvist G, Ingelsson M, Sehlin D. Altered amyloid-β structure markedly reduces gliosis in the brain of mice harboring the Uppsala APP deletion. Acta Neuropathol Commun 2024; 12:22. [PMID: 38317196 PMCID: PMC10845526 DOI: 10.1186/s40478-024-01734-x] [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: 10/17/2023] [Accepted: 01/14/2024] [Indexed: 02/07/2024] Open
Abstract
Deposition of amyloid beta (Aβ) into plaques is a major hallmark of Alzheimer's disease (AD). Different amyloid precursor protein (APP) mutations cause early-onset AD by altering the production or aggregation properties of Aβ. We recently identified the Uppsala APP mutation (APPUpp), which causes Aβ pathology by a triple mechanism: increased β-secretase and altered α-secretase APP cleavage, leading to increased formation of a unique Aβ conformer that rapidly aggregates and deposits in the brain. The aim of this study was to further explore the effects of APPUpp in a transgenic mouse model (tg-UppSwe), expressing human APP with the APPUpp mutation together with the APPSwe mutation. Aβ pathology was studied in tg-UppSwe brains at different ages, using ELISA and immunohistochemistry. In vivo PET imaging with three different PET radioligands was conducted in aged tg-UppSwe mice and two other mouse models; tg-ArcSwe and tg-Swe. Finally, glial responses to Aβ pathology were studied in cell culture models and mouse brain tissue, using ELISA and immunohistochemistry. Tg-UppSwe mice displayed increased β-secretase cleavage and suppressed α-secretase cleavage, resulting in AβUpp42 dominated diffuse plaque pathology appearing from the age of 5-6 months. The γ-secretase cleavage was not affected. Contrary to tg-ArcSwe and tg-Swe mice, tg-UppSwe mice were [11C]PiB-PET negative. Antibody-based PET with the 3D6 ligand visualized Aβ pathology in all models, whereas the Aβ protofibril selective mAb158 ligand did not give any signals in tg-UppSwe mice. Moreover, unlike the other two models, tg-UppSwe mice displayed a very faint glial response to the Aβ pathology. The tg-UppSwe mouse model thus recapitulates several pathological features of the Uppsala APP mutation carriers. The presumed unique structural features of AβUpp42 aggregates were found to affect their interaction with anti-Aβ antibodies and profoundly modify the Aβ-mediated glial response, which may be important aspects to consider for further development of AD therapies.
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Affiliation(s)
- María Pagnon de la Vega
- Department of Public Health and Caring Sciences, Geriatrics, Uppsala University, Uppsala, Sweden
| | - Stina Syvänen
- Department of Public Health and Caring Sciences, Geriatrics, Uppsala University, Uppsala, Sweden
| | - Vilmantas Giedraitis
- Department of Public Health and Caring Sciences, Geriatrics, Uppsala University, Uppsala, Sweden
| | - Monique Hooley
- UK Dementia Research Institute, Edinburgh Medical School, University of Edinburgh, Edinburgh, UK
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
| | - Evangelos Konstantinidis
- Department of Public Health and Caring Sciences, Geriatrics, Uppsala University, Uppsala, Sweden
| | - Silvio R Meier
- Department of Public Health and Caring Sciences, Geriatrics, Uppsala University, Uppsala, Sweden
| | - Johanna Rokka
- Department of Public Health and Caring Sciences, Geriatrics, Uppsala University, Uppsala, Sweden
| | - Jonas Eriksson
- Department of Medicinal Chemistry, Division of Organic Pharmaceutical Chemistry, Uppsala University, Uppsala, Sweden
- PET Centre, Uppsala University Hospital, Uppsala, Sweden
| | - Ximena Aguilar
- Department of Public Health and Caring Sciences, Geriatrics, Uppsala University, Uppsala, Sweden
| | - Tara L Spires-Jones
- UK Dementia Research Institute, Edinburgh Medical School, University of Edinburgh, Edinburgh, UK
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK
| | - Lars Lannfelt
- Department of Public Health and Caring Sciences, Geriatrics, Uppsala University, Uppsala, Sweden
- BioArctic AB, Stockholm, Sweden
| | - Lars N G Nilsson
- Department of Pharmacology, University of Oslo and Oslo University Hospital, Oslo, Norway
| | - Anna Erlandsson
- Department of Public Health and Caring Sciences, Geriatrics, Uppsala University, Uppsala, Sweden
| | | | - Martin Ingelsson
- Department of Public Health and Caring Sciences, Geriatrics, Uppsala University, Uppsala, Sweden
- Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Tanz Centre for Research in Neurodegenerative Diseases, Departments of Medicine and Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| | - Dag Sehlin
- Department of Public Health and Caring Sciences, Geriatrics, Uppsala University, Uppsala, Sweden.
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de Gea P, Benkeder S, Bouvet P, Aimard M, Chounlamountri N, Honnorat J, Do LD, Meissirel C. VEGF controls microglial phagocytic response to amyloid-β. Front Cell Neurosci 2023; 17:1264402. [PMID: 38162003 PMCID: PMC10757340 DOI: 10.3389/fncel.2023.1264402] [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: 07/20/2023] [Accepted: 11/23/2023] [Indexed: 01/03/2024] Open
Abstract
Microglial cells are well known to be implicated in the pathogenesis of Alzheimer's disease (AD), due to the impaired clearance of amyloid-β (Aβ) protein. In AD, Aβ accumulates in the brain parenchyma as soluble oligomers and protofibrils, and its aggregation process further give rise to amyloid plaques. Compelling evidence now indicate that Aβ oligomers (Aβo) are the most toxic forms responsible for neuronal and synaptic alterations. Recently, we showed that the Vascular Endothelial Growth Factor (VEGF) counteracts Aβo-induced synaptic alterations and that a peptide derived from VEGF is able to inhibit Aβ aggregation process. Moreover, VEGF has been reported to promote microglial chemotaxis to Aβ brain deposits. We therefore investigated whether VEGF could influence microglial phagocytic response to Aβ, using in vitro and ex vivo models of amyloid accumulation. We report here that VEGF increases Aβo phagocytosis by microglial cells and further characterized the molecular basis of the VEGF effect. VEGF is able to control α-secretase activity in microglial cells, resulting in the increased cleavage of the Triggering Receptor Expressed on Myeloid cells 2 (TREM2), a major microglial Aβ receptor. Consistently, the soluble form sTREM2 also increases Aβo phagocytosis by microglial cells. Taken together, these findings propose VEGF as a new regulator of Aβ clearance and suggest its potential role in rescuing compromised microglial function in AD.
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Affiliation(s)
- Priscille de Gea
- Laboratory MeLIS, Institut Neuromyogène, Synaptopathies and Autoantibodies, INSERM U1314, CNRS UMR 5284, Université Claude Bernard Lyon 1, Lyon, France
| | - Sarah Benkeder
- Laboratory MeLIS, Institut Neuromyogène, Synaptopathies and Autoantibodies, INSERM U1314, CNRS UMR 5284, Université Claude Bernard Lyon 1, Lyon, France
| | - Pauline Bouvet
- Laboratory MeLIS, Institut Neuromyogène, Synaptopathies and Autoantibodies, INSERM U1314, CNRS UMR 5284, Université Claude Bernard Lyon 1, Lyon, France
| | - Mélanie Aimard
- Laboratory MeLIS, Institut Neuromyogène, Synaptopathies and Autoantibodies, INSERM U1314, CNRS UMR 5284, Université Claude Bernard Lyon 1, Lyon, France
| | - Naura Chounlamountri
- Laboratory MeLIS, Institut Neuromyogène, Synaptopathies and Autoantibodies, INSERM U1314, CNRS UMR 5284, Université Claude Bernard Lyon 1, Lyon, France
| | - Jérôme Honnorat
- Laboratory MeLIS, Institut Neuromyogène, Synaptopathies and Autoantibodies, INSERM U1314, CNRS UMR 5284, Université Claude Bernard Lyon 1, Lyon, France
- French Reference Center for Paraneoplastic Neurological Syndromes and Autoimmune Encephalitis, Hospices Civils de Lyon, Hôpital Neurologique Pierre Wertheimer, Bron, France
| | - Le Duy Do
- Laboratory MeLIS, Institut Neuromyogène, Synaptopathies and Autoantibodies, INSERM U1314, CNRS UMR 5284, Université Claude Bernard Lyon 1, Lyon, France
- French Reference Center for Paraneoplastic Neurological Syndromes and Autoimmune Encephalitis, Hospices Civils de Lyon, Hôpital Neurologique Pierre Wertheimer, Bron, France
| | - Claire Meissirel
- Laboratory MeLIS, Institut Neuromyogène, Synaptopathies and Autoantibodies, INSERM U1314, CNRS UMR 5284, Université Claude Bernard Lyon 1, Lyon, France
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15
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Levites Y, Dammer EB, Ran Y, Tsering W, Duong D, Abreha M, Gadhavi J, Lolo K, Trejo-Lopez J, Phillips JL, Iturbe A, Erqiuzi A, Moore BD, Ryu D, Natu A, Dillon KD, Torrellas J, Moran C, Ladd TB, Afroz KF, Islam T, Jagirdar J, Funk CC, Robinson M, Borchelt DR, Ertekin-Taner N, Kelly JW, Heppner FL, Johnson EC, McFarland K, Levey AL, Prokop S, Seyfried NT, Golde TE. Aβ Amyloid Scaffolds the Accumulation of Matrisome and Additional Proteins in Alzheimer's Disease. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.29.568318. [PMID: 38076912 PMCID: PMC10705437 DOI: 10.1101/2023.11.29.568318] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/14/2024]
Abstract
We report a highly significant correlation in brain proteome changes between Alzheimers disease (AD) and CRND8 APP695NL/F transgenic mice. However, integrating protein changes observed in the CRND8 mice with co-expression networks derived from human AD, reveals both conserved and divergent module changes. For the most highly conserved module (M42, matrisome) we find many proteins accumulate in plaques, cerebrovascular amyloid (CAA), dystrophic processes, or a combination thereof. Overexpression of two M42 proteins, midkine (Mdk) and pleiotrophin (PTN), in CRND8 mice brains leads to increased accumulation of A β ; in plaques and in CAA; further, recombinant MDK and PTN enhance A β ; aggregation into amyloid. Multiple M42 proteins, annotated as heparan sulfate binding proteins, bind to fibrillar A β 42 and a non-human amyloid fibril in vitro. Supporting this binding data, MDK and PTN co-accumulate with transthyretin (TTR) amyloid in the heart and islet amyloid polypeptide (IAPP) amyloid in the pancreas. Our findings establish several critical insights. Proteomic changes in modules observed in human AD brains define an A β ; amyloid responsome that is well conserved from mouse model to human. Further, distinct amyloid structures may serve as scaffolds, facilitating the co-accumulation of proteins with signaling functions. We hypothesize that this co-accumulation may contribute to downstream pathological sequalae. Overall, this contextualized understanding of proteomic changes and their interplay with amyloid deposition provides valuable insights into the complexity of AD pathogenesis and potential biomarkers and therapeutic targets.
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16
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Mackiewicz J, Lisek M, Boczek T. Targeting CaN/NFAT in Alzheimer's brain degeneration. Front Immunol 2023; 14:1281882. [PMID: 38077352 PMCID: PMC10701682 DOI: 10.3389/fimmu.2023.1281882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Accepted: 11/06/2023] [Indexed: 12/18/2023] Open
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder characterized by a progressive loss of cognitive functions. While the exact causes of this debilitating disorder remain elusive, numerous investigations have characterized its two core pathologies: the presence of β-amyloid plaques and tau tangles. Additionally, multiple studies of postmortem brain tissue, as well as results from AD preclinical models, have consistently demonstrated the presence of a sustained inflammatory response. As the persistent immune response is associated with neurodegeneration, it became clear that it may also exacerbate other AD pathologies, providing a link between the initial deposition of β-amyloid plaques and the later development of neurofibrillary tangles. Initially discovered in T cells, the nuclear factor of activated T-cells (NFAT) is one of the main transcription factors driving the expression of inflammatory genes and thus regulating immune responses. NFAT-dependent production of inflammatory mediators is controlled by Ca2+-dependent protein phosphatase calcineurin (CaN), which dephosphorylates NFAT and promotes its transcriptional activity. A substantial body of evidence has demonstrated that aberrant CaN/NFAT signaling is linked to several pathologies observed in AD, including neuronal apoptosis, synaptic deficits, and glia activation. In view of this, the role of NFAT isoforms in AD has been linked to disease progression at different stages, some of which are paralleled to diminished cognitive status. The use of classical inhibitors of CaN/NFAT signaling, such as tacrolimus or cyclosporine, or adeno-associated viruses to specifically inhibit astrocytic NFAT activation, has alleviated some symptoms of AD by diminishing β-amyloid neurotoxicity and neuroinflammation. In this article, we discuss the recent findings related to the contribution of CaN/NFAT signaling to the progression of AD and highlight the possible benefits of targeting this pathway in AD treatment.
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Affiliation(s)
| | | | - Tomasz Boczek
- Department of Molecular Neurochemistry, Medical University of Lodz, Lodz, Poland
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Sudwarts A, Thinakaran G. Alzheimer's genes in microglia: a risk worth investigating. Mol Neurodegener 2023; 18:90. [PMID: 37986179 PMCID: PMC10662636 DOI: 10.1186/s13024-023-00679-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2023] [Accepted: 11/07/2023] [Indexed: 11/22/2023] Open
Abstract
Despite expressing many key risk genes, the role of microglia in late-onset Alzheimer's disease pathophysiology is somewhat ambiguous, with various phenotypes reported to be either harmful or protective. Herein, we review some key findings from clinical and animal model investigations, discussing the role of microglial genetics in mediating perturbations from homeostasis. We note that impairment to protective phenotypes may include prolonged or insufficient microglial activation, resulting in dysregulated metabolomic (notably lipid-related) processes, compounded by age-related inflexibility in dynamic responses. Insufficiencies of mouse genetics and aggressive transgenic modelling imply severe limitations in applying current methodologies for aetiological investigations. Despite the shortcomings, widely used amyloidosis and tauopathy models of the disease have proven invaluable in dissecting microglial functional responses to AD pathophysiology. Some recent advances have brought modelling tools closer to human genetics, increasing the validity of both aetiological and translational endeavours.
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Affiliation(s)
- Ari Sudwarts
- Byrd Alzheimer's Center and Research Institute, University of South Florida, Tampa, FL, 33613, USA.
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL, 33612, USA.
| | - Gopal Thinakaran
- Byrd Alzheimer's Center and Research Institute, University of South Florida, Tampa, FL, 33613, USA.
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL, 33612, USA.
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Kwak C, Finan GM, Park YR, Garg A, Harari O, Mun JY, Rhee HW, Kim TW. Proximity Proteome Analysis Reveals Novel TREM2 Interactors in the ER-Mitochondria Interface of Human Microglia. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.21.533722. [PMID: 38014048 PMCID: PMC10680561 DOI: 10.1101/2023.03.21.533722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
Triggering receptor expressed on myeloid cells 2 (TREM2) plays a central role in microglial biology and the pathogenesis of Alzheimer's disease (AD). Besides DNAX-activating protein 12 (DAP12), a communal adaptor for TREM2 and many other receptors, other cellular interactors of TREM2 remain largely elusive. We employed a 'proximity labeling' approach using a biotin ligase, TurboID, for mapping protein-protein interactions in live mammalian cells. We discovered novel TREM2-proximal proteins with diverse functions, including those localized to the Mitochondria-ER contact sites (MERCs), a dynamic subcellular 'hub' implicated in a number of crucial cell physiology such as lipid metabolism. TREM2 deficiency alters the thickness (inter-organelle distance) of MERCs, a structural parameter of metabolic state, in microglia derived from human induced pluripotent stem cells. Our TurboID-based TREM2 interactome study suggest novel roles for TREM2 in the structural plasticity of the MERCs, raising the possibility that dysregulation of MERC-related TREM2 functions contribute to AD pathobiology.
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Abstract
Triggering receptors expressed on myeloid cells (TREMs) encompass a family of cell-surface receptors chiefly expressed by granulocytes, monocytes and tissue macrophages. These receptors have been implicated in inflammation, neurodegenerative diseases, bone remodelling, metabolic syndrome, atherosclerosis and cancer. Here, I review the structure, ligands, signalling modes and functions of TREMs in humans and mice and discuss the challenges that remain in understanding TREM biology.
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Affiliation(s)
- Marco Colonna
- Department of Pathology and Immunology, Washington University School of Medicine, St Louis, MO, USA.
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20
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Rego S, Sanchez G, Da Mesquita S. Current views on meningeal lymphatics and immunity in aging and Alzheimer's disease. Mol Neurodegener 2023; 18:55. [PMID: 37580702 PMCID: PMC10424377 DOI: 10.1186/s13024-023-00645-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Accepted: 08/02/2023] [Indexed: 08/16/2023] Open
Abstract
Alzheimer's disease (AD) is an aging-related form of dementia associated with the accumulation of pathological aggregates of amyloid beta and neurofibrillary tangles in the brain. These phenomena are accompanied by exacerbated inflammation and marked neuronal loss, which altogether contribute to accelerated cognitive decline. The multifactorial nature of AD, allied to our still limited knowledge of its etiology and pathophysiology, have lessened our capacity to develop effective treatments for AD patients. Over the last few decades, genome wide association studies and biomarker development, alongside mechanistic experiments involving animal models, have identified different immune components that play key roles in the modulation of brain pathology in AD, affecting its progression and severity. As we will relay in this review, much of the recent efforts have been directed to better understanding the role of brain innate immunity, and particularly of microglia. However, and despite the lack of diversity within brain resident immune cells, the brain border tissues, especially the meninges, harbour a considerable number of different types and subtypes of adaptive and innate immune cells. Alongside microglia, which have taken the centre stage as important players in AD research, there is new and exciting evidence pointing to adaptive immune cells, namely T and B cells found in the brain and its meninges, as important modulators of neuroinflammation and neuronal (dys)function in AD. Importantly, a genuine and functional lymphatic vascular network is present around the brain in the outermost meningeal layer, the dura. The meningeal lymphatics are directly connected to the peripheral lymphatic system in different mammalian species, including humans, and play a crucial role in preserving a "healthy" immune surveillance of the CNS, by shaping immune responses, not only locally at the meninges, but also at the level of the brain tissue. In this review, we will provide a comprehensive view on our current knowledge about the meningeal lymphatic vasculature, emphasizing its described roles in modulating CNS fluid and macromolecule drainage, meningeal and brain immunity, as well as glial and neuronal function in aging and in AD.
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Affiliation(s)
- Shanon Rego
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
- Post-baccalaureate Research Education Program, Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Guadalupe Sanchez
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
- Neuroscience Ph.D. Program, Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Sandro Da Mesquita
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA.
- Post-baccalaureate Research Education Program, Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic, Jacksonville, FL, 32224, USA.
- Neuroscience Ph.D. Program, Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic, Jacksonville, FL, 32224, USA.
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21
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Lee CYD, De La Rocha AJ, Inouye K, Langfelder P, Daggett A, Gu X, Jiang LL, Pamonag Z, Vaca RG, Richman J, Kawaguchi R, Gao F, Xu H, Yang XW. BAC Transgenic Expression of Human TREM2-R47H Remodels Amyloid Plaques but Unable to Reprogram Plaque-associated Microglial Reactivity in 5xFAD Mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.03.551881. [PMID: 37577582 PMCID: PMC10418161 DOI: 10.1101/2023.08.03.551881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
Background Genetic study of late-onset Alzheimer's disease (AD) reveals that a rare Arginine-to-Histamine mutation at amino acid residue 47 (R47H) in Triggering Receptor Expressed on Myeloid Cells 2 (TREM2) results in increased disease risk. TREM2 plays critical roles in regulating microglial response to amyloid plaques in AD, leading to their clustering and activation surrounding the plaques. We previously showed that increasing human TREM2 gene dosage exerts neuroprotective effects against AD-related deficits in amyloid depositing mouse models of AD. However, the in vivo effects of the R47H mutation on human TREM2-mediated microglial reprogramming and neuroprotection remains poorly understood. Method Here we created a BAC transgenic mouse model expressing human TREM2 with the R47H mutation in its cognate genomic context (BAC-TREM2-R47H). Importantly, the BAC used in this study was engineered to delete critical exons of other TREM-like genes on the BAC to prevent confounding effects of overexpressing multiple TREM-like genes. We crossed BAC-TREM2- R47H mice with 5xFAD [1], an amyloid depositing mouse model of AD, to evaluate amyloid pathologies and microglial phenotypes, transcriptomics and in situ expression of key TREM2 -dosage dependent genes. We also compared the key findings in 5xFAD/BAC-TREM2-R47H to those observed in 5xFAD/BAC-TREM2 mice. Result Both BAC-TREM2 and BAC-TREM2-R47H showed proper expression of three splicing isoforms of TREM2 that are normally found in human. In 5xFAD background, elevated TREM2-R47H gene dosages significantly reduced the plaque burden, especially the filamentous type. The results were consistent with enhanced phagocytosis and altered NLRP3 inflammasome activation in BAC- TREM2-R47H microglia in vitro. However, unlike TREM2 overexpression, elevated TREM2- R47H in 5xFAD failed to ameliorate cognitive and transcriptomic deficits. In situ analysis of key TREM2 -dosage dependent genes and microglial morphology uncovered that TREM2-R47H showed a loss-of-function phenotype in reprogramming of plaque-associated microglial reactivity and gene expression in 5xFAD. Conclusion Our study demonstrated that the AD-risk variant has a previously unknown, mixture of partial and full loss of TREM2 functions in modulating microglial response in AD mouse brains. Together, our new BAC-TREM2-R47H model and prior BAC-TREM2 mice are invaluable resource to facilitate the therapeutic discovery that target human TREM2 and its R47H variant to ameliorate AD and other neurodegenerative disorders.
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Yamamoto S, Masuda T. Lipid in microglial biology - from material to mediator. Inflamm Regen 2023; 43:38. [PMID: 37460930 PMCID: PMC10351166 DOI: 10.1186/s41232-023-00289-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Accepted: 07/06/2023] [Indexed: 07/20/2023] Open
Abstract
Microglia are resident macrophages in the central nervous system (CNS) that play various roles during brain development and in the pathogenesis of CNS diseases. Recently, reprogramming of cellular energetic metabolism in microglia has drawn attention as a crucial mechanism for diversification of microglial functionality. Lipids are highly diverse materials and crucial components of cell membranes in every cell. Accumulating evidence has shown that lipid and its metabolism are tightly involved in microglial biology. In this review, we summarize the current knowledge about microglial lipid metabolism in health and disease.
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Affiliation(s)
- Shota Yamamoto
- Division of Molecular Neuroimmunology, Medical Institute of Bioregulation, Kyushu University, Fukuoka, 812-8582, Japan.
| | - Takahiro Masuda
- Division of Molecular Neuroimmunology, Medical Institute of Bioregulation, Kyushu University, Fukuoka, 812-8582, Japan.
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23
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Leri M, Vasarri M, Carnemolla F, Oriente F, Cabaro S, Stio M, Degl'Innocenti D, Stefani M, Bucciantini M. EVOO Polyphenols Exert Anti-Inflammatory Effects on the Microglia Cell through TREM2 Signaling Pathway. Pharmaceuticals (Basel) 2023; 16:933. [PMID: 37513845 PMCID: PMC10384320 DOI: 10.3390/ph16070933] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 06/08/2023] [Accepted: 06/12/2023] [Indexed: 07/30/2023] Open
Abstract
In Alzheimer's disease (AD), microglia, brain resident immune cells, become chronically inflammatory and neurotoxic. In recent years, neuroinflammation has attracted particular interest in the scientific community. The genetic variants of molecules associated with ''microgliopathies'', including the triggering receptor expressed in myeloid cells-2 (TREM2), result in increased risk of developing AD and cognitive decline. We performed a set of in vitro assays using human neuronal (SH-SY5Y) and microglial (BV2 and C13NJ) cell models. Cells were differentially treated with extra virgin olive oil (EVOO) polyphenols, oleuropein aglycone (OleA) and hydroxytyrosol (HT) before adding LPS. We evaluated the protective effects of these EVOO products by a set of biochemical and cell biology assays, including ELISA, MTT, ROS detection, Western blotting and immunofluorescence. Our results provide an integrated understanding of the neuroprotection exerted by polyphenols in terms of: (i) reduction of pro-inflammatory cytokines release (IL-6, IL-8, IP-10 and RANTES); (ii) activation of the TREM2-dependent anti-inflammatory pathway; (iii) enhancement of protective microglial activity favoring the M2 polarization phenotype. Such findings provide new and important insights into the mechanisms by which the dietary olive polyphenols exert beneficial properties against neuroinflammation and neuronal impairment.
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Affiliation(s)
- Manuela Leri
- Dipartimento di Scienze Biomediche Sperimentali e Cliniche "Mario Serio", Università degli Studi di Firenze, 50134 Firenze, Italy
| | - Marzia Vasarri
- Dipartimento di Scienze Biomediche Sperimentali e Cliniche "Mario Serio", Università degli Studi di Firenze, 50134 Firenze, Italy
| | - Federica Carnemolla
- Dipartimento di Scienze Biomediche Sperimentali e Cliniche "Mario Serio", Università degli Studi di Firenze, 50134 Firenze, Italy
| | - Francesco Oriente
- Dipartimento di Scienze Mediche Traslazionali, Università di Napoli Federico II, 80138 Napoli, Italy
| | - Serena Cabaro
- Dipartimento di Scienze Mediche Traslazionali, Università di Napoli Federico II, 80138 Napoli, Italy
| | - Maria Stio
- Dipartimento di Scienze Biomediche Sperimentali e Cliniche "Mario Serio", Università degli Studi di Firenze, 50134 Firenze, Italy
| | - Donatella Degl'Innocenti
- Dipartimento di Scienze Biomediche Sperimentali e Cliniche "Mario Serio", Università degli Studi di Firenze, 50134 Firenze, Italy
| | - Massimo Stefani
- Dipartimento di Scienze Biomediche Sperimentali e Cliniche "Mario Serio", Università degli Studi di Firenze, 50134 Firenze, Italy
| | - Monica Bucciantini
- Dipartimento di Scienze Biomediche Sperimentali e Cliniche "Mario Serio", Università degli Studi di Firenze, 50134 Firenze, Italy
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24
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Yin T, D’Adamio L. BRI2-mediated regulation of TREM2 processing in microglia and its potential implications for Alzheimer's disease and related dementias. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.14.544924. [PMID: 37398330 PMCID: PMC10312752 DOI: 10.1101/2023.06.14.544924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
ITM2B/BRI2 mutations cause familial forms of Alzheimer's disease (AD)-related dementias by disrupting BRI2's protein function and leading to the accumulation of amyloidogenic peptides. Although typically studied in neurons, our findings show that BRI2 is highly expressed in microglia, which are crucial in AD pathogenesis due to the association of variants in the microglial gene TREM2 with increased AD risk. Our single-cell RNAseq (scRNAseq) analysis revealed a microglia cluster that depends on a Trem2 activity that is inhibited by Bri2, pointing to a functional interaction between Itm2b/Bri2 and Trem2. Given that the AD-related Amyloid-β Precursor protein (APP) and TREM2 undergo similar proteolytic processing, and that BRI2 inhibits APP processing, we hypothesized that BRI2 may also regulate TREM2 processing. We found that BRI2 interacts with Trem2 and inhibits its processing by α-secretase in transfected cells. In mice lacking Bri2 expression, we observed increased central nervous system (CNS) levels of Trem2-CTF and sTrem2, which are the products of α-secretase processing of Trem2, indicating increased Trem2 processing by α-secretase in vivo. Reducing Bri2 expression only in microglia resulted in increased sTrem2 levels, suggesting a cell-autonomous effect of Bri2 on α-secretase processing of Trem2. Our study reveals a previously unknow role of BRI2 in regulating TREM2-related neurodegenerative mechanisms. The ability of BRI2 to regulate the processing of both APP and TREM2, combined with its cell-autonomous role in neurons and microglia, makes it a promising candidate for the development of AD and AD-related dementias therapeutics.
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Affiliation(s)
- Tao Yin
- Department of Pharmacology, Physiology & Neuroscience New Jersey Medical School, Brain Health Institute, Jacqueline Krieger Klein Center in Alzheimer’s Disease and Neurodegeneration Research, Rutgers, The State University of New Jersey, 205 South Orange Ave, Newark, NJ, 07103, USA
| | - Luciano D’Adamio
- Department of Pharmacology, Physiology & Neuroscience New Jersey Medical School, Brain Health Institute, Jacqueline Krieger Klein Center in Alzheimer’s Disease and Neurodegeneration Research, Rutgers, The State University of New Jersey, 205 South Orange Ave, Newark, NJ, 07103, USA
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25
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Ennerfelt H, Holliday C, Shapiro D, Zengeler K, Bolte A, Ulland T, Lukens J. CARD9 attenuates Aβ pathology and modifies microglial responses in an Alzheimer's disease mouse model. Proc Natl Acad Sci U S A 2023; 120:e2303760120. [PMID: 37276426 PMCID: PMC10268238 DOI: 10.1073/pnas.2303760120] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Accepted: 04/04/2023] [Indexed: 06/07/2023] Open
Abstract
Recent advances have highlighted the importance of several innate immune receptors expressed by microglia in Alzheimer's disease (AD). In particular, mounting evidence from AD patients and experimental models indicates pivotal roles for TREM2, CD33, and CD22 in neurodegenerative disease progression. While there is growing interest in targeting these microglial receptors to treat AD, we still lack knowledge of the downstream signaling molecules used by these receptors to orchestrate immune responses in AD. Notably, TREM2, CD33, and CD22 have been described to influence signaling associated with the intracellular adaptor molecule CARD9 to mount downstream immune responses outside of the brain. However, the role of CARD9 in AD remains poorly understood. Here, we show that genetic ablation of CARD9 in the 5xFAD mouse model of AD results in exacerbated amyloid beta (Aβ) deposition, increased neuronal loss, worsened cognitive deficits, and alterations in microglial responses. We further show that pharmacological activation of CARD9 promotes improved clearance of Aβ deposits from the brains of 5xFAD mice. These results help to establish CARD9 as a key intracellular innate immune signaling molecule that regulates Aβ-mediated disease and microglial responses. Moreover, these findings suggest that targeting CARD9 might offer a strategy to improve Aβ clearance in AD.
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Affiliation(s)
- Hannah Ennerfelt
- Department of Neuroscience, Center for Brain Immunology and Glia, University of Virginia, Charlottesville, VA22908
- Neuroscience Graduate Program, University of Virginia, Charlottesville, VA22908
- Cell and Molecular Biology Graduate Training Program, University of Virginia, Charlottesville, VA22908
| | - Coco Holliday
- Department of Neuroscience, Center for Brain Immunology and Glia, University of Virginia, Charlottesville, VA22908
| | - Daniel A. Shapiro
- Department of Neuroscience, Center for Brain Immunology and Glia, University of Virginia, Charlottesville, VA22908
| | - Kristine E. Zengeler
- Department of Neuroscience, Center for Brain Immunology and Glia, University of Virginia, Charlottesville, VA22908
- Neuroscience Graduate Program, University of Virginia, Charlottesville, VA22908
- Cell and Molecular Biology Graduate Training Program, University of Virginia, Charlottesville, VA22908
| | - Ashley C. Bolte
- Department of Neuroscience, Center for Brain Immunology and Glia, University of Virginia, Charlottesville, VA22908
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia, Charlottesville, VA22908
- Medical Scientist Training Program, University of Virginia, Charlottesville, VA22908
| | - Tyler K. Ulland
- Department of Pathology and Laboratory Medicine, University of Wisconsin, Madison, WI53705
| | - John R. Lukens
- Department of Neuroscience, Center for Brain Immunology and Glia, University of Virginia, Charlottesville, VA22908
- Neuroscience Graduate Program, University of Virginia, Charlottesville, VA22908
- Cell and Molecular Biology Graduate Training Program, University of Virginia, Charlottesville, VA22908
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia, Charlottesville, VA22908
- Medical Scientist Training Program, University of Virginia, Charlottesville, VA22908
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Lyu S, Lan Z, Li C. The triggering receptor expressed on myeloid cells 2-apolipoprotein E signaling pathway in diseases. Chin Med J (Engl) 2023; 136:1291-1299. [PMID: 37130227 PMCID: PMC10309513 DOI: 10.1097/cm9.0000000000002167] [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: 08/15/2022] [Indexed: 05/04/2023] Open
Abstract
ABSTRACT Triggering receptor expressed on myeloid cells 2 (TREM2) is a membrane receptor on myeloid cells and plays an important role in the body's immune defense. Recently, TREM2 has received extensive attention from researchers, and its activity has been found in Alzheimer's disease, neuroinflammation, and traumatic brain injury. The appearance of TREM2 is usually accompanied by changes in apolipoprotein E (ApoE), and there has been a lot of research into their structure, as well as the interaction mode and signal pathways involved in them. As two molecules with broad and important roles in the human body, understanding their correlation may provide therapeutic targets for certain diseases. In this article, we reviewed several diseases in which TREM2 and ApoE are synergistically involved in the development. We further discussed the positive or negative effects of the TREM2-ApoE pathway on nervous system immunity and inflammation.
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Affiliation(s)
- Shukai Lyu
- Department of General Practice, The Fourth Affiliated Hospital, School of Medicine, Zhejiang University, Yiwu, Zhejiang 322000, China
| | - Zhuoqing Lan
- Department of General Practice, The Fourth Affiliated Hospital, School of Medicine, Zhejiang University, Yiwu, Zhejiang 322000, China
| | - Caixia Li
- Department of General Practice, The Fourth Affiliated Hospital, School of Medicine, Zhejiang University, Yiwu, Zhejiang 322000, China
- The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang 310003, China
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27
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Johnson AM, Lukens JR. The innate immune response in tauopathies. Eur J Immunol 2023; 53:e2250266. [PMID: 36932726 PMCID: PMC10247424 DOI: 10.1002/eji.202250266] [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: 01/06/2023] [Revised: 02/23/2023] [Accepted: 03/15/2023] [Indexed: 03/19/2023]
Abstract
Tauopathies, which include frontotemporal dementia, Alzheimer's disease, and chronic traumatic encephalopathy, are a class of neurological disorders resulting from pathogenic tau aggregates. These aggregates disrupt neuronal health and function leading to the cognitive and physical decline of tauopathy patients. Genome-wide association studies and clinical evidence have brought to light the large role of the immune system in inducing and driving tau-mediated pathology. More specifically, innate immune genes are found to harbor tauopathy risk alleles, and innate immune pathways are upregulated throughout the course of disease. Experimental evidence has expanded on these findings by describing pivotal roles for the innate immune system in the regulation of tau kinases and tau aggregates. In this review, we summarize the literature implicating innate immune pathways as drivers of tauopathy.
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Affiliation(s)
- Alexis M. Johnson
- Center for Brain Immunology and Glia (BIG), Department of Neuroscience, University of Virginia (UVA), Charlottesville, VA 22908, USA
- Neuroscience Graduate Program, UVA, Charlottesville, VA 22908, USA
- BIG Training Graduate Program, UVA, Charlottesville, VA 22908, USA
| | - John R. Lukens
- Center for Brain Immunology and Glia (BIG), Department of Neuroscience, University of Virginia (UVA), Charlottesville, VA 22908, USA
- Neuroscience Graduate Program, UVA, Charlottesville, VA 22908, USA
- BIG Training Graduate Program, UVA, Charlottesville, VA 22908, USA
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28
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Thu VTA, Hoang TX, Kim JY. 1,25-Dihydroxy Vitamin D 3 Facilitates the M2 Polarization and β-Amyloid Uptake by Human Microglia in a TREM2-Dependent Manner. BIOMED RESEARCH INTERNATIONAL 2023; 2023:3483411. [PMID: 37274074 PMCID: PMC10239306 DOI: 10.1155/2023/3483411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 04/23/2023] [Accepted: 05/17/2023] [Indexed: 06/06/2023]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder characterized by dementia as the primary clinical symptom. The production and accumulation of aggregated β-amyloid (Aβ) in patient brain tissues is one of the hallmarks of AD pathogenesis. Microglia, brain-resident macrophages, produce inflammatory cytokines in response to Aβ oligomers or fibrils exacerbating Aβ pathology in AD. HMO6 cells were treated with Aβ42 in the presence or absence of 1,25-dihydroxy vitamin D3 (1,25(OH)2D3) to determine its potential immunomodulatory effects, and the expression of pro-/anti-inflammatory cytokines, M1/M2-associated markers, Toll-like receptors (TLRs), and triggering receptor expressed on myeloid cells 2 (TREM2) was examined. 1,25(OH)2D3 was found to suppress Aβ-induced expression of proinflammatory cytokines (TNF-α, IL-1β, and IL-6), M1 markers (CD86 and iNOS), and TLR2/4, whilst increasing the expression of anti-inflammatory cytokines (IL-4, IL-10, and CCL17) and M2 markers (CD206 and Arg-1). Furthermore, 1,25(OH)2D3 promoted TREM2 expression and Aβ uptake by HMO6 cells, and the enhancement of Aβ uptake and M2 polarization was revealed to be TREM2-dependent. The findings of this study suggest that 1,25(OH)2D3 facilitates M2 polarization and Aβ uptake in a TREM2-dependent manner.
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Affiliation(s)
- Vo Thuy Anh Thu
- Department of Life Science, Gachon University, Seongnam, Gyeonggi-do 13120, Republic of Korea
| | - Thi Xoan Hoang
- Department of Life Science, Gachon University, Seongnam, Gyeonggi-do 13120, Republic of Korea
| | - Jae Young Kim
- Department of Life Science, Gachon University, Seongnam, Gyeonggi-do 13120, Republic of Korea
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29
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Lefterov I, Fitz NF, Lu Y, Koldamova R. APOEε4 and risk of Alzheimer's disease - time to move forward. Front Neurosci 2023; 17:1195724. [PMID: 37274212 PMCID: PMC10235508 DOI: 10.3389/fnins.2023.1195724] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 05/02/2023] [Indexed: 06/06/2023] Open
Abstract
The inheritance of Apolipoprotein E4 (APOEε4) brings the highest genetic risk of Alzheimer's disease (AD), arguably the highest genetic risk in human pathology. Since the discovery of the association, APOE protein isoforms have been at the center of tens of thousands of studies and reports. While, without a doubt, our knowledge about the normal physiological function of APOE isoforms in the brain has increased tremendously, the questions of how the inheritance of the APOEε4 allele translates into a risk of AD, and the risk is materialized, remain unanswered. Moreover, the knowledge about the risk associated with APOEε4 has not helped design a meaningful preventative or therapeutic strategy. Animal models with targeted replacement of Apoe have been generated and, thanks to the recent NIH/NIA/Alzheimer's disease Association initiative, are now freely available to AD researchers. While helpful in many aspects, none of the available models recapitulates normal physiological transcriptional regulation of the human APOE gene cluster. Changes in epigenetic regulation of APOE alleles in animal models in response to external insults have rarely been if ever, addressed. However, these animal models provide a useful tool to handle questions and investigate protein-protein interactions with proteins expressed by other recently discovered genes and gene variants considered genetic risk factors of AD, like Triggering Receptor expressed on Myeloid cells 2 (TREM2). In this review, we discuss genetic and epigenetic regulatory mechanisms controlling and influencing APOE expression and focus on interactions of APOE and TREM2 in the context of microglia and astrocytes' role in AD-like pathology in animal models.
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Lau V, Ramer L, Tremblay MÈ. An aging, pathology burden, and glial senescence build-up hypothesis for late onset Alzheimer's disease. Nat Commun 2023; 14:1670. [PMID: 36966157 PMCID: PMC10039917 DOI: 10.1038/s41467-023-37304-3] [Citation(s) in RCA: 35] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Accepted: 03/07/2023] [Indexed: 03/27/2023] Open
Abstract
Alzheimer's disease (AD) predominantly occurs as a late onset (LOAD) form involving neurodegeneration and cognitive decline with progressive memory loss. Risk factors that include aging promote accumulation of AD pathologies, such as amyloid-beta and tau aggregates, as well as inflammation and oxidative stress. Homeostatic glial states regulate and suppress pathology buildup; inflammatory states exacerbate pathology by releasing pro-inflammatory cytokines. Multiple stresses likely induce glial senescence, which could decrease supportive functions and reinforce inflammation. In this perspective, we hypothesize that aging first drives AD pathology burden, whereafter AD pathology putatively induces glial senescence in LOAD. We hypothesize that increasing glial senescence, particularly local senescent microglia accumulation, sustains and drives perpetuating buildup and spread of AD pathologies, glial aging, and further senescence. We predict that increasing glial senescence, particularly local senescent microglia accumulation, also transitions individuals from healthy cognition into mild cognitive impairment and LOAD diagnosis. These pathophysiological underpinnings may centrally contribute to LOAD onset, but require further mechanistic investigation.
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Affiliation(s)
- Victor Lau
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada.
- Institute on Aging and Lifelong Health, University of Victoria, Victoria, BC, Canada.
- Centre for Advanced Materials and Related Technology (CAMTEC), University of Victoria, Victoria, BC, Canada.
| | - Leanne Ramer
- Department of Biomedical Physiology & Kinesiology, Simon Fraser University, Burnaby, BC, Canada.
| | - Marie-Ève Tremblay
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada.
- Institute on Aging and Lifelong Health, University of Victoria, Victoria, BC, Canada.
- Centre for Advanced Materials and Related Technology (CAMTEC), University of Victoria, Victoria, BC, Canada.
- 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.
- 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.
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Qiao W, Chen Y, Zhong J, Madden BJ, Charlesworth CM, Martens YA, Liu CC, Knight J, Ikezu TC, Kurti A, Zhu Y, Meneses A, Rosenberg CL, Kuchenbecker LA, Vanmaele LK, Li F, Chen K, Shue F, Dacquel MV, Fryer J, Pandey A, Zhao N, Bu G. Trem2 H157Y increases soluble TREM2 production and reduces amyloid pathology. Mol Neurodegener 2023; 18:8. [PMID: 36721205 PMCID: PMC9890893 DOI: 10.1186/s13024-023-00599-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 01/19/2023] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND The rare p.H157Y variant of TREM2 (Triggering Receptor Expressed on Myeloid Cells 2) was found to increase Alzheimer's disease (AD) risk. This mutation is located at the cleavage site of TREM2 extracellular domain. Ectopic expression of TREM2-H157Y in HEK293 cells resulted in increased TREM2 shedding. However, the physiological outcomes of the TREM2 H157Y mutation remain unknown in the absence and presence of AD related pathologies. METHODS We generated a novel Trem2 H157Y knock-in mouse model through CRISPR/Cas9 technology and investigated the effects of Trem2 H157Y on TREM2 proteolytic processing, synaptic function, and AD-related amyloid pathologies by conducting biochemical assays, targeted mass spectrometry analysis of TREM2, hippocampal electrophysiology, immunofluorescent staining, in vivo micro-dialysis, and cortical bulk RNA sequencing. RESULTS Consistent with previous in vitro findings, Trem2 H157Y increases TREM2 shedding with elevated soluble TREM2 levels in the brain and serum. Moreover, Trem2 H157Y enhances synaptic plasticity without affecting microglial density and morphology, or TREM2 signaling. In the presence of amyloid pathology, Trem2 H157Y accelerates amyloid-β (Aβ) clearance and reduces amyloid burden, dystrophic neurites, and gliosis in two independent founder lines. Targeted mass spectrometry analysis of TREM2 revealed higher ratios of soluble to full-length TREM2-H157Y compared to wild-type TREM2, indicating that the H157Y mutation promotes TREM2 shedding in the presence of Aβ. TREM2 signaling was further found reduced in Trem2 H157Y homozygous mice. Transcriptomic profiling revealed that Trem2 H157Y downregulates neuroinflammation-related genes and an immune module correlated with the amyloid pathology. CONCLUSION Taken together, our findings suggest beneficial effects of the Trem2 H157Y mutation in synaptic function and in mitigating amyloid pathology. Considering the genetic association of TREM2 p.H157Y with AD risk, we speculate TREM2 H157Y in humans might increase AD risk through an amyloid-independent pathway, such as its effects on tauopathy and neurodegeneration which merit further investigation.
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Affiliation(s)
- Wenhui Qiao
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA
| | - Yixing Chen
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA
| | - Jun Zhong
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN 55905 USA
| | - Benjamin J. Madden
- Medical Genome Facility, Proteomics Core, Mayo Clinic, Rochester, MN USA
| | | | - Yuka A. Martens
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA
| | - Chia-Chen Liu
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA
| | - Joshua Knight
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA
| | | | - Aishe Kurti
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA
| | - Yiyang Zhu
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA
| | - Axel Meneses
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA
| | | | | | - Lucy K. Vanmaele
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA
| | - Fuyao Li
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA
| | - Kai Chen
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA
| | - Francis Shue
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA
| | | | - John Fryer
- Department of Neuroscience, Mayo Clinic, Scottsdale, AZ 85259 USA
| | - Akhilesh Pandey
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN 55905 USA
- Center for Individualized Medicine, Mayo Clinic, Rochester, MN USA
- Manipal Academy of Higher Education (MAHE), Manipal, Karnataka 576104 India
| | - Na Zhao
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA
| | - Guojun Bu
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224 USA
- SciNeuro Pharmaceuticals, Rockville, MD 20805 USA
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32
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Basha SKC, Ramaiah MJ, Kosagisharaf JR. Untangling the Role of TREM2 in Conjugation with Microglia in Neuronal Dysfunction: A Hypothesis on a Novel Pathway in the Pathophysiology of Alzheimer's Disease. J Alzheimers Dis 2023; 94:S319-S333. [PMID: 36683512 PMCID: PMC10473115 DOI: 10.3233/jad-221070] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/17/2022] [Indexed: 01/21/2023]
Abstract
Alzheimer's disease (AD) is a complex neurodegenerative disorder involving heterogenous pathophysiological characteristics, which has become a challenge to therapeutics. The major pathophysiology of AD comprises amyloid-β (Aβ), tau, oxidative stress, and apoptosis. Recent studies indicate the significance of Triggering receptor expressed on myeloid cells 2 (TREM2) and its mutant variants in AD. TREM2 are the transmembrane receptors of microglial cells that performs a broad range of physiological cell processes. Phagocytosis of Aβ is one of the physiological roles of TREM2, which plays a pivotal role in AD progression. R47H, a mutant variant of TREM2, increases the risk of AD by impairing TREM2-Aβ binding. Inconclusive evidence regarding the TREM2 signaling cascade mechanism of Aβ phagocytosis motivates the current review to propose a new hypothesis. The review systematically assesses the cross talk between TREM2 and other AD pathological domains and the influence of TREM2 on amyloid and tau seeding. Disease associated microglia (DAM), a novel state of microglia with unique transcriptional and functional signatures reported in neurodegenerative conditions, also depend on the TREM2 pathway for its differentiation. DAM is suggested to have a neuroprotective role. We hypothesize that TREM2, along with its signaling adaptors and endogenous proteins, play a key role in ameliorating Aβ clearance. We indicate that TREM2 has the potential to ameliorate the Aβ burden, though with differential clearance ability and may act as a potential therapeutic target.
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Affiliation(s)
- SK Chand Basha
- Department of Bio-Technology, Koneru Lakshmaiah Education Foundation, Vaddeswaram, AP, India
| | - Mekala Janaki Ramaiah
- Department of Bio-Technology, Koneru Lakshmaiah Education Foundation, Vaddeswaram, AP, India
| | - Jagannatha Rao Kosagisharaf
- Department of Bio-Technology, Koneru Lakshmaiah Education Foundation, Vaddeswaram, AP, India
- National Science System (SENACYT), INDICASAT – AIP, Panama
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Hou J, Chen Y, Grajales-Reyes G, Colonna M. TREM2 dependent and independent functions of microglia in Alzheimer's disease. Mol Neurodegener 2022; 17:84. [PMID: 36564824 PMCID: PMC9783481 DOI: 10.1186/s13024-022-00588-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Accepted: 12/02/2022] [Indexed: 12/25/2022] Open
Abstract
Microglia are central players in brain innate immunity and have been the subject of extensive research in Alzheimer's disease (AD). In this review, we aim to summarize the genetic and functional discoveries that have advanced our understanding of microglia reactivity to AD pathology. Given the heightened AD risk posed by rare variants of the microglial triggering receptor expressed on myeloid cells 2 (TREM2), we will focus on the studies addressing the impact of this receptor on microglia responses to amyloid plaques, tauopathy and demyelination pathologies in mouse and human. Finally, we will discuss the implications of recent discoveries on microglia and TREM2 biology on potential therapeutic strategies for AD.
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Affiliation(s)
- Jinchao Hou
- grid.4367.60000 0001 2355 7002Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110 USA
| | - Yun Chen
- grid.4367.60000 0001 2355 7002Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110 USA ,grid.4367.60000 0001 2355 7002Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110 USA
| | - Gary Grajales-Reyes
- grid.4367.60000 0001 2355 7002Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110 USA
| | - Marco Colonna
- grid.4367.60000 0001 2355 7002Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110 USA
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Bandow K, Smith A, Garlick J. Soluble triggering receptor expressed on myeloid cells 2 (sTREM2) positively regulates lipopolysaccharide-induced expression of CXC chemokine ligand 10 and 11 in mouse macrophages. Biochem Biophys Res Commun 2022; 635:227-235. [DOI: 10.1016/j.bbrc.2022.10.048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Accepted: 10/12/2022] [Indexed: 11/30/2022]
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35
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Yasuno F, Watanabe A, Kimura Y, Yamauchi Y, Ogata A, Ikenuma H, Abe J, Minami H, Nihashi T, Yokoi K, Hattori S, Shimoda N, Kasuga K, Ikeuchi T, Takeda A, Sakurai T, Ito K, Kato T. Estimation of blood-based biomarkers of glial activation related to neuroinflammation. Brain Behav Immun Health 2022; 26:100549. [PMID: 36388135 PMCID: PMC9650015 DOI: 10.1016/j.bbih.2022.100549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 10/08/2022] [Accepted: 10/30/2022] [Indexed: 11/07/2022] Open
Abstract
Background Neuroinflammation is a well-known feature of Alzheimer’s disease (AD), and a blood-based test for estimating the levels of neuroinflammation would be expected. In this study, we examined and validated a model using blood-based biomarkers to predict the level of glial activation due to neuroinflammation, as estimated by 11C-DPA-713 positron emission tomography (PET) imaging. Methods We included 15 patients with AD and 10 cognitively normal (CN) subjects. Stepwise backward deletion multiple regression analysis was used to determine the predictors of the TSPO-binding potential (BPND) estimated by PET imaging. The independent variables were age, sex, diagnosis, apolipoprotein E4 positivity, body mass index and the serum concentration of blood-based biomarkers, including monocyte chemotactic protein 1 (MCP-1), fractalkine, chitinase 3-like protein-1 (CHI3L1), soluble triggering receptor expressed on myeloid cells 2 (sTREM2), and clusterin. Results Sex, diagnosis, and serum concentrations of MCP1 and sTREM2 were determined as predictors of TSPO-BPND in the Braak1-3 area. The serum concentrations of MCP1 and sTREM2 correlated positively with TSPO-BPND. In a leave one out (LOO) cross-validation (CV) analysis, the model gave a LOO CV R2 of 0.424, which indicated that this model can account for approximately 42.4% of the variance of brain TSPO-BPND. Conclusions We found that the model including serum MCP-1 and sTREM2 concentration and covariates of sex and diagnosis was the best for predicting brain TSPO-BPND. The detection of neuroinflammation in AD patients by blood-based biomarkers should be a sensitive and useful tool for making an early diagnosis and monitoring disease progression and treatment effectiveness.
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Li K, Ran B, Wang Y, Liu L, Li W. PLCγ2 impacts microglia-related effectors revealing variants and pathways important in Alzheimer’s disease. Front Cell Dev Biol 2022; 10:999061. [PMID: 36147734 PMCID: PMC9485805 DOI: 10.3389/fcell.2022.999061] [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: 07/20/2022] [Accepted: 08/15/2022] [Indexed: 11/30/2022] Open
Abstract
Alzheimer’s disease (AD) is an irreversible neurodegenerative disease mainly characterized by memory loss and cognitive decline. The etiology of AD is complex and remains incompletely understood. In recent years, genome-wide association studies (GWAS) have increasingly highlighted the central role of microglia in AD pathology. As a trans-membrane receptor specifically present on the microglia in the central nervous system, phosphatidylinositol-specific phospholipase C gamma 2 (PLCγ2) plays an important role in neuroinflammation. GWAS data and corresponding pathological research have explored the effects of PLCG2 variants on amyloid burden and tau pathologies that underline AD. The link between PLCγ2 and other AD-related effectors in human and mouse microglia has also been established, placing PLCγ2 downstream of the triggering receptor expressed on myeloid cells 2 (TREM2), toll-like receptor 4 (TLR4), Bruton’s tyrosine kinase (BTK), and colony-stimulating factor 1 receptor (CSF1R). Because the research on PLCγ2’s role in AD is still in its early stages, few articles have been published, therefore in this paper, we integrate the relevant research published to date, review the structural features, expression patterns, and related pathways of PLCγ2, and summarize the recent studies on important PLCG2 variants related to AD. Furthermore, the possibility and challenge of using PLCγ2 to develop therapeutic drugs for AD are also discussed.
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37
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Haure-Mirande JV, Audrain M, Ehrlich ME, Gandy S. Microglial TYROBP/DAP12 in Alzheimer's disease: Transduction of physiological and pathological signals across TREM2. Mol Neurodegener 2022; 17:55. [PMID: 36002854 PMCID: PMC9404585 DOI: 10.1186/s13024-022-00552-w] [Citation(s) in RCA: 44] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Accepted: 06/27/2022] [Indexed: 02/01/2023] Open
Abstract
TYROBP (also known as DAP12 or KARAP) is a transmembrane adaptor protein initially described as a receptor-activating subunit component of natural killer (NK) cells. TYROBP is expressed in numerous cell types, including peripheral blood monocytes, macrophages, dendritic cells, and osteoclasts, but a key point of recent interest is related to the critical role played by TYROBP in the function of many receptors expressed on the plasma membrane of microglia. TYROBP is the downstream adaptor and putative signaling partner for several receptors implicated in Alzheimer's disease (AD), including SIRP1β, CD33, CR3, and TREM2. TYROBP has received much of its current notoriety because of its importance in brain homeostasis by signal transduction across those receptors. In this review, we provide an overview of evidence indicating that the biology of TYROBP extends beyond its interaction with these four ligand-binding ectodomain-intramembranous domain molecules. In addition to reviewing the structure and localization of TYROBP, we discuss our recent progress using mouse models of either cerebral amyloidosis or tauopathy that were engineered to be TYROBP-deficient or TYROBP-overexpressing. Remarkably, constitutively TYROBP-deficient mice provided a model of genetic resilience to either of the defining proteinopathies of AD. Learning behavior and synaptic electrophysiological function were preserved at normal physiological levels even in the face of robust cerebral amyloidosis (in APP/PSEN1;Tyrobp-/- mice) or tauopathy (in MAPTP301S;Tyrobp-/- mice). A fundamental underpinning of the functional synaptic dysfunction associated with each proteotype was an accumulation of complement C1q. TYROBP deficiency prevented C1q accumulation associated with either proteinopathy. Based on these data, we speculate that TYROBP plays a key role in the microglial sensome and the emergence of the disease-associated microglia (DAM) phenotype. TYROBP may also play a key role in the loss of markers of synaptic integrity (e.g., synaptophysin-like immunoreactivity) that has long been held to be the feature of human AD molecular neuropathology that most closely correlates with concurrent clinical cognitive function.
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Affiliation(s)
| | - Mickael Audrain
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
| | - Michelle E. Ehrlich
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
- Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
| | - Sam Gandy
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
- Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
- Department of Psychiatry and the NIA-Designated Mount Sinai Alzheimer’s Disease Research Center, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
- James J Peters VA Medical Center, New York, Bronx NY 10468 USA
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38
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Benarroch E. What Is the Role of Microglial Metabolism in Inflammation and Neurodegeneration? Neurology 2022; 99:99-105. [PMID: 35851556 DOI: 10.1212/wnl.0000000000200920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 05/16/2022] [Indexed: 11/15/2022] Open
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Profile of TREM2-Derived circRNA and mRNA Variants in the Entorhinal Cortex of Alzheimer’s Disease Patients. Int J Mol Sci 2022; 23:ijms23147682. [PMID: 35887031 PMCID: PMC9320643 DOI: 10.3390/ijms23147682] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 07/04/2022] [Accepted: 07/04/2022] [Indexed: 02/04/2023] Open
Abstract
Genetic variants in TREM2, a microglia-related gene, are well-known risk factors for Alzheimer’s disease (AD). Here, we report that TREM2 originates from circular RNAs (circRNAs), a novel class of non-coding RNAs characterized by a covalent and stable closed-loop structure. First, divergent primers were designed to amplify circRNAs by RT-PCR, which were further assessed by Sanger sequencing. Then, additional primer sets were used to confirm back-splicing junctions. In addition, HMC3 cells were used to assess the microglial expression of circTREM2s. Three candidate circTREM2s were identified in control and AD human entorhinal samples. One of the circRNAs, circTREM2_1, was consistently amplified by all divergent primer sets in control and AD entorhinal cortex samples as well as in HMC3 cells. In AD cases, a moderate negative correlation (r = −0.434) was found between the global average area of Aβ deposits in the entorhinal cortex and circTREM2_1 expression level. In addition, by bioinformatics tools, a total of 16 miRNAs were predicted to join with circTREM2s. Finally, TREM2 mRNA corresponding to four isoforms was profiled by RT-qPCR. TREM2 mRNA levels were found elevated in entorhinal samples of AD patients with low or intermediate ABC scores compared to controls. To sum up, a novel circRNA derived from the TREM2 gene, circTREM2_1, has been identified in the human entorhinal cortex and TREM2 mRNA expression has been detected to increase in AD compared to controls. Unraveling the molecular genetics of the TREM2 gene may help to better know the innate immune response in AD.
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Long HZ, Zhou ZW, Cheng Y, Luo HY, Li FJ, Xu SG, Gao LC. The Role of Microglia in Alzheimer’s Disease From the Perspective of Immune Inflammation and Iron Metabolism. Front Aging Neurosci 2022; 14:888989. [PMID: 35847685 PMCID: PMC9284275 DOI: 10.3389/fnagi.2022.888989] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Accepted: 06/13/2022] [Indexed: 12/25/2022] Open
Abstract
Alzheimer’s disease (AD), the most common type of senile dementia, includes the complex pathogenesis of abnormal deposition of amyloid beta-protein (Aβ), phosphorylated tau (p-tau) and neuroimmune inflammatory. The neurodegenerative process of AD triggers microglial activation, and the overactivation of microglia produces a large number of neuroimmune inflammatory factors. Microglia dysfunction can lead to disturbances in iron metabolism and enhance iron-induced neuronal degeneration in AD, while elevated iron levels in brain areas affect microglia phenotype and function. In this manuscript, we firstly discuss the role of microglia in AD and then introduce the role of microglia in the immune-inflammatory pathology of AD. Their role in AD iron homeostasis is emphasized. Recent studies on microglia and ferroptosis in AD are also reviewed. It will help readers better understand the role of microglia in iron metabolism in AD, and provides a basis for better regulation of iron metabolism disorders in AD and the discovery of new potential therapeutic targets for AD.
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Affiliation(s)
- Hui-Zhi Long
- School of Pharmacy, The Affiliated Changsha Central Hospital, Hengyang Medical School, University of South China, Changsha, China
- Hunan Provincial Key Laboratory of Tumor Microenvironment Responsive Drug Research, Hengyang, China
| | - Zi-Wei Zhou
- School of Pharmacy, The Affiliated Changsha Central Hospital, Hengyang Medical School, University of South China, Changsha, China
- Hunan Provincial Key Laboratory of Tumor Microenvironment Responsive Drug Research, Hengyang, China
| | - Yan Cheng
- School of Pharmacy, The Affiliated Changsha Central Hospital, Hengyang Medical School, University of South China, Changsha, China
- Hunan Provincial Key Laboratory of Tumor Microenvironment Responsive Drug Research, Hengyang, China
| | - Hong-Yu Luo
- School of Pharmacy, The Affiliated Changsha Central Hospital, Hengyang Medical School, University of South China, Changsha, China
- Hunan Provincial Key Laboratory of Tumor Microenvironment Responsive Drug Research, Hengyang, China
| | - Feng-Jiao Li
- School of Pharmacy, The Affiliated Changsha Central Hospital, Hengyang Medical School, University of South China, Changsha, China
- Hunan Provincial Key Laboratory of Tumor Microenvironment Responsive Drug Research, Hengyang, China
| | - Shuo-Guo Xu
- School of Pharmacy, The Affiliated Changsha Central Hospital, Hengyang Medical School, University of South China, Changsha, China
- Hunan Provincial Key Laboratory of Tumor Microenvironment Responsive Drug Research, Hengyang, China
| | - Li-Chen Gao
- School of Pharmacy, The Affiliated Changsha Central Hospital, Hengyang Medical School, University of South China, Changsha, China
- Hunan Provincial Key Laboratory of Tumor Microenvironment Responsive Drug Research, Hengyang, China
- *Correspondence: Li-Chen Gao,
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Mai Z, Wei W, Yu H, Chen Y, Wang Y, Ding Y. Molecular recognition of the interaction between ApoE and the TREM2 protein. Transl Neurosci 2022; 13:93-103. [PMID: 35582645 PMCID: PMC9055258 DOI: 10.1515/tnsci-2022-0218] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 04/04/2022] [Accepted: 04/04/2022] [Indexed: 11/15/2022] Open
Abstract
Alzheimer’s disease (AD) is the most common type of dementia. The ε4 allele of the apolipoprotein E (ApoE) gene is the strongest known genetic risk factor for late-onset AD. Triggering receptor expressed on myeloid cells 2 (TREM2) is another important risk factor affecting the AD process after ApoE. Emerging evidence has identified TREM2 as a putative receptor for ApoE, raising the possibility that interactions between ApoE and TREM2 modulate the pathogenesis of AD. In this study, we performed molecular docking and molecular dynamics (MD) analyses to characterize the ApoE–TREM2 interaction and further investigated the effect of the major TREM2 disease-associated mutation (R47H) on the affinity of TREM2 for ApoE. The results indicate that the binding energy between ApoE and TREM2 occurs in an isoform-dependent manner with the following potency rank order: ApoE4 > ApoE3 > ApoE2. In addition, the R47H mutant reduced the interaction between ApoE and TREM2 protein, which may be attributed to decreased hydrogen-bonding interactions, hydrophobic interactions, and electrostatic forces between ApoE and TREM2. Our study analyzed the molecular pattern of the interactions between ApoE and TREM2 and how the variants affect these interactions based on in silico modeling, and the results might help to elucidate the interaction mechanism between ApoE and TREM2. Additional experimental studies will be needed to verify and explore the current findings.
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Affiliation(s)
- Zhenhua Mai
- Department of Critical Care Medicine, Affiliated Hospital of Guangdong Medical University , Zhanjiang 524023 , China
| | - Wenyan Wei
- Department of Gerontology, Affiliated Hospital of Guangdong Medical University , Zhanjiang 524023 , China
| | - Haibin Yu
- Department of Epidemiology and Health Statistics, School of Public Health, Guangdong Medical University , Dongguan 523808 , China
| | - Yongze Chen
- Department of Epidemiology and Health Statistics, School of Public Health, Guangdong Medical University , Dongguan 523808 , China
| | - Yongxiang Wang
- Department of Rehabilitation Medicine, Affiliated Hospital of Guangdong Medical University , Zhanjiang 524023 , China
| | - Yuanlin Ding
- Department of Epidemiology and Health Statistics, School of Public Health, Guangdong Medical University , Dongguan 523808 , China
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Golde TE. Alzheimer’s disease – the journey of a healthy brain into organ failure. Mol Neurodegener 2022; 17:18. [PMID: 35248124 PMCID: PMC8898417 DOI: 10.1186/s13024-022-00523-1] [Citation(s) in RCA: 43] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 02/17/2022] [Indexed: 12/19/2022] Open
Abstract
As the most common dementia, Alzheimer’s disease (AD) exacts an immense personal, societal, and economic toll. AD was first described at the neuropathological level in the early 1900s. Today, we have mechanistic insight into select aspects of AD pathogenesis and have the ability to clinically detect and diagnose AD and underlying AD pathologies in living patients. These insights demonstrate that AD is a complex, insidious, degenerative proteinopathy triggered by Aβ aggregate formation. Over time Aβ pathology drives neurofibrillary tangle (NFT) pathology, dysfunction of virtually all cell types in the brain, and ultimately, overt neurodegeneration. Yet, large gaps in our knowledge of AD pathophysiology and huge unmet medical need remain. Though we largely conceptualize AD as a disease of aging, heritable and non-heritable factors impact brain physiology, either continuously or at specific time points during the lifespan, and thereby alter risk for devolvement of AD. Herein, I describe the lifelong journey of a healthy brain from birth to death with AD, while acknowledging the many knowledge gaps that remain regarding our understanding of AD pathogenesis. To ensure the current lexicon surrounding AD changes from inevitable, incurable, and poorly manageable to a lexicon of preventable, curable, and manageable we must address these knowledge gaps, develop therapies that have a bigger impact on clinical symptoms or progression of disease and use these interventions at the appropriate stage of disease.
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Metformin in Alzheimer’s disease: An overview of potential mechanisms, preclinical and clinical findings. Biochem Pharmacol 2022; 197:114945. [DOI: 10.1016/j.bcp.2022.114945] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 02/01/2022] [Accepted: 02/02/2022] [Indexed: 12/13/2022]
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Soluble TREM2 inhibits secondary nucleation of Aβ fibrillization and enhances cellular uptake of fibrillar Aβ. Proc Natl Acad Sci U S A 2022; 119:2114486119. [PMID: 35082148 PMCID: PMC8812518 DOI: 10.1073/pnas.2114486119] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/13/2021] [Indexed: 01/21/2023] Open
Abstract
Triggering receptor expressed on myeloid cells 2 (TREM2) is a single-pass transmembrane receptor of the immunoglobulin superfamily that is secreted in a soluble (sTREM2) form. Mutations in TREM2 have been linked to increased risk of Alzheimer's disease (AD). A prominent neuropathological component of AD is deposition of the amyloid-β (Aβ) into plaques, particularly Aβ40 and Aβ42. While the membrane-bound form of TREM2 is known to facilitate uptake of Aβ fibrils and the polarization of microglial processes toward amyloid plaques, the role of its soluble ectodomain, particularly in interactions with monomeric or fibrillar Aβ, has been less clear. Our results demonstrate that sTREM2 does not bind to monomeric Aβ40 and Aβ42, even at a high micromolar concentration, while it does bind to fibrillar Aβ42 and Aβ40 with equal affinities (2.6 ± 0.3 µM and 2.3 ± 0.4 µM). Kinetic analysis shows that sTREM2 inhibits the secondary nucleation step in the fibrillization of Aβ, while having little effect on the primary nucleation pathway. Furthermore, binding of sTREM2 to fibrils markedly enhanced uptake of fibrils into human microglial and neuroglioma derived cell lines. The disease-associated sTREM2 mutant, R47H, displayed little to no effect on fibril nucleation and binding, but it decreased uptake and functional responses markedly. We also probed the structure of the WT sTREM2-Aβ fibril complex using integrative molecular modeling based primarily on the cross-linking mass spectrometry data. The model shows that sTREM2 binds fibrils along one face of the structure, leaving a second, mutation-sensitive site free to mediate cellular binding and uptake.
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Variant TREM2 Signaling in Alzheimer's Disease. J Mol Biol 2022; 434:167470. [PMID: 35120968 DOI: 10.1016/j.jmb.2022.167470] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 01/25/2022] [Accepted: 01/27/2022] [Indexed: 12/25/2022]
Abstract
Alzheimer's disease is the most common form of dementia, accounting for as much as three-quarters of cases globally with individuals in low- and middle-income countries being worst affected. Numerous risk factors for the disease have been identified and our understanding of gene-environment interactions have shed light on several gene variants that contribute to the most common, sporadic form of Alzheimer's disease. Triggering Receptor Expressed on Myeloid cells 2 (TREM2) is an important receptor that is crucial to the functioning of microglial cells, and variants of this protein have been found to be associated with a significantly increased risk of Alzheimer's disease. Several studies have elucidated the signaling processes involved in the normal functioning of the TREM2 receptor. However, current knowledge of the idiosyncrasies of the signaling processes triggered by stimulation of the variants of this receptor is limited. In this review, we examine the existing literature and highlight the effects that various receptor variants have on downstream signaling processes and discuss how these perturbations may affect physiologic processes in Alzheimer's disease. Despite the fact that this is a territory yet to be fully explored, the studies that currently exist report mostly quantitative effects on signaling. More mechanistic studies with the aim of providing qualitative results in terms of downstream signaling among these receptor variants are warranted. Such studies will provide better opportunities of identifying therapeutic targets that may be exploited in designing new drugs for the management of Alzheimer's disease.
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Brown GC, St George-Hyslop P. Does Soluble TREM2 Protect Against Alzheimer's Disease? Front Aging Neurosci 2022; 13:834697. [PMID: 35153729 PMCID: PMC8831327 DOI: 10.3389/fnagi.2021.834697] [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: 12/13/2021] [Accepted: 12/31/2021] [Indexed: 02/02/2023] Open
Abstract
Triggering Receptor Expressed in Myeloid Cells 2 (TREM2) is a pattern recognition receptor on myeloid cells, and is upregulated on microglia surrounding amyloid plaques in Alzheimer's disease (AD). Rare, heterozygous mutations in TREM2 (e.g., R47H) increase AD risk several fold. TREM2 can be cleaved at the plasma membrane by metalloproteases to release the ectodomain as soluble TREM2 (sTREM2). Wild-type sTREM2 binds oligomeric amyloid beta (Aβ) and acts as an extracellular chaperone, blocking and reversing Aβ oligomerization and fibrillization, and preventing Aβ-induced neuronal loss in vitro. Whereas, R47H sTREM2 increases Aβ fibrillization and neurotoxicity. AD brains expressing R47H TREM2 have more fibrous plaques with more neuritic pathology around these plaques, consistent with R47H sTREM2 promoting Aβ fibrillization relative to WT sTREM2. Brain expression or injection of wild-type sTREM2 reduces pathology in amyloid models of AD in mice, indicating that wild-type sTREM2 is protective against amyloid pathology. Levels of sTREM2 in cerebrospinal fluid (CSF) fall prior to AD, rise in early AD, and fall again in late AD. People with higher sTREM2 levels in CSF progress more slowly into and through AD than do people with lower sTREM2 levels, suggesting that sTREM2 protects against AD. However, some of these experiments can be interpreted as full-length TREM2 protecting rather than sTREM2, and to distinguish between these two possibilities, we need more experiments testing whether sTREM2 itself protects in AD and AD models, and at what stage of disease. If sTREM2 is protective, then treatments could be designed to elevate sTREM2 in AD.
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Affiliation(s)
- Guy C. Brown
- Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom,*Correspondence: Guy C. Brown
| | - Peter St George-Hyslop
- Department of Medicine, University of Cambridge, Cambridge, United Kingdom,Department of Medicine, University of Toronto, Toronto, ON, Canada
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Sheng X, Yao Y, Huang R, Xu Y, Zhu Y, Chen L, Zhang L, Wang W, Zhuo R, Can D, Chang CF, Zhang YW, Xu H, Bu G, Zhong L, Chen XF. Identification of the minimal active soluble TREM2 sequence for modulating microglial phenotypes and amyloid pathology. J Neuroinflammation 2021; 18:286. [PMID: 34893068 PMCID: PMC8665564 DOI: 10.1186/s12974-021-02340-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2021] [Accepted: 12/02/2021] [Indexed: 11/24/2022] Open
Abstract
Background TREM2 is a microglial receptor genetically linked to the risk for Alzheimer’s disease (AD). The cerebrospinal fluid (CSF) levels of soluble TREM2 (sTREM2) have emerged as a valuable biomarker for the disease progression in AD and higher CSF levels of sTREM2 are linked to slower cognitive decline. Increasing sTREM2 in mouse models of amyloidosis reduces amyloid-related pathology through modulating microglial functions, suggesting a beneficial role of sTREM2 in microglia biology and AD pathology. Methods In the current study, we performed serial C- and N-terminal truncations of sTREM2 protein to define the minimal sequence requirement for sTREM2 function. We initially assessed the impacts of sTREM2 mutants on microglial functions by measuring cell viability and inflammatory responses. The binding of the sTREM2 mutants to oligomeric Aβ was determined by solid-phase protein binding assay and dot blot assay. We further evaluated the impacts of sTREM2 mutants on amyloid-related pathology by direct stereotaxic injection of sTREM2 proteins into the brain of 5xFAD mice. Results We found that both sTREM2 fragments 41–81 and 51–81 enhance cell viability and inflammatory responses in primary microglia. However, the fragment 51–81 exhibited impaired affinity to oligomeric Aβ. When administrated to the 5xFAD mice brain, the sTREM2 fragment 41–81, but not 51–81, increased the number of plaque-associated microglia and reduced the plaque deposition. Interestingly, the fragment 41–81 was more efficient than the physiological form of sTREM2 in ameliorating Aβ-related pathology. Conclusions Our results indicate that the interaction of sTREM2 truncated variants with Aβ is essential for enhancing microglial recruitment to the vicinity of an amyloid plaque and reducing the plaque load. Importantly, we identified a 41-amino acid sequence of sTREM2 that is sufficient for modulating microglial functions and more potent than the full-length sTREM2 in reducing the plaque load and the plaque-associated neurotoxicity. Taken together, our data provide more insights into the mechanisms underlying sTREM2 function and the minimal active sTREM2 sequence represents a promising candidate for AD therapy.
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Affiliation(s)
- Xuan Sheng
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, 361102, China
| | - Yunling Yao
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, 361102, China
| | - Ruizhi Huang
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, 361102, China
| | - Ying Xu
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, 361102, China
| | - Yifei Zhu
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, 361102, China
| | - Linting Chen
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, 361102, China
| | - Lianshuai Zhang
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, 361102, China
| | - Wanbing Wang
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, 361102, China
| | - Rengong Zhuo
- Xiamen Key Laboratory of Chiral Drugs, School of Medicine, Xiamen University, Xiamen, 361102, China.,Shenzhen Research Institute of Xiamen University, Shenzhen, 518063, China
| | - Dan Can
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, 361102, China
| | - Che-Feng Chang
- Graduate Institute of Physiology, College of Medicine, National Taiwan University, Taipei, 10051, Taiwan
| | - Yun-Wu Zhang
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, 361102, China
| | - Huaxi Xu
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, 361102, China
| | - Guojun Bu
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Li Zhong
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, 361102, China.
| | - Xiao-Fen Chen
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, 361102, China. .,Shenzhen Research Institute of Xiamen University, Shenzhen, 518063, China.
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Li Y, Laws SM, Miles LA, Wiley JS, Huang X, Masters CL, Gu BJ. Genomics of Alzheimer's disease implicates the innate and adaptive immune systems. Cell Mol Life Sci 2021; 78:7397-7426. [PMID: 34708251 PMCID: PMC11073066 DOI: 10.1007/s00018-021-03986-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 09/14/2021] [Accepted: 10/16/2021] [Indexed: 02/08/2023]
Abstract
Alzheimer's disease (AD) is a chronic neurodegenerative disease characterised by cognitive impairment, behavioural alteration, and functional decline. Over 130 AD-associated susceptibility loci have been identified by genome-wide association studies (GWAS), while whole genome sequencing (WGS) and whole exome sequencing (WES) studies have identified AD-associated rare variants. These variants are enriched in APOE, TREM2, CR1, CD33, CLU, BIN1, CD2AP, PILRA, SCIMP, PICALM, SORL1, SPI1, RIN3, and more genes. Given that aging is the single largest risk factor for late-onset AD (LOAD), the accumulation of somatic mutations in the brain and blood of AD patients have also been explored. Collectively, these genetic findings implicate the role of innate and adaptive immunity in LOAD pathogenesis and suggest that a systemic failure of cell-mediated amyloid-β (Aβ) clearance contributes to AD onset and progression. AD-associated variants are particularly enriched in myeloid-specific regulatory regions, implying that AD risk variants are likely to perturbate the expression of myeloid-specific AD-associated genes to interfere Aβ clearance. Defective phagocytosis, endocytosis, and autophagy may drive Aβ accumulation, which may be related to naturally-occurring antibodies to Aβ (Nabs-Aβ) produced by adaptive responses. Passive immunisation is providing efficiency in clearing Aβ and slowing cognitive decline, such as aducanumab, donanemab, and lecanemab (ban2401). Causation of AD by impairment of the innate immunity and treatment using the tools of adaptive immunity is emerging as a new paradigm for AD, but immunotherapy that boosts the innate immune functions of myeloid cells is highly expected to modulate disease progression at asymptomatic stage.
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Affiliation(s)
- Yihan Li
- The Florey Institute, The University of Melbourne, 30 Royal Parade, Parkville, VIC, 3052, Australia
| | - Simon M Laws
- Centre for Precision Health, Edith Cowan University, 270 Joondalup Dr, Joondalup, WA, 6027, Australia
- Collaborative Genomics and Translation Group, School of Medical and Health Sciences, Edith Cowan University, 270 Joondalup Dr, Joondalup, WA, 6027, Australia
| | - Luke A Miles
- The Florey Institute, The University of Melbourne, 30 Royal Parade, Parkville, VIC, 3052, Australia
| | - James S Wiley
- The Florey Institute, The University of Melbourne, 30 Royal Parade, Parkville, VIC, 3052, Australia
| | - Xin Huang
- The Florey Institute, The University of Melbourne, 30 Royal Parade, Parkville, VIC, 3052, Australia
| | - Colin L Masters
- The Florey Institute, The University of Melbourne, 30 Royal Parade, Parkville, VIC, 3052, Australia
| | - Ben J Gu
- The Florey Institute, The University of Melbourne, 30 Royal Parade, Parkville, VIC, 3052, Australia.
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Chu E, Mychasiuk R, Hibbs ML, Semple BD. Dysregulated phosphoinositide 3-kinase signaling in microglia: shaping chronic neuroinflammation. J Neuroinflammation 2021; 18:276. [PMID: 34838047 PMCID: PMC8627624 DOI: 10.1186/s12974-021-02325-6] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2021] [Accepted: 11/15/2021] [Indexed: 12/15/2022] Open
Abstract
Microglia are integral mediators of innate immunity within the mammalian central nervous system. Typical microglial responses are transient, intending to restore homeostasis by orchestrating the removal of pathogens and debris and the regeneration of damaged neurons. However, prolonged and persistent microglial activation can drive chronic neuroinflammation and is associated with neurodegenerative disease. Recent evidence has revealed that abnormalities in microglial signaling pathways involving phosphatidylinositol 3-kinase (PI3K) and protein kinase B (AKT) may contribute to altered microglial activity and exacerbated neuroimmune responses. In this scoping review, the known and suspected roles of PI3K-AKT signaling in microglia, both during health and pathological states, will be examined, and the key microglial receptors that induce PI3K-AKT signaling in microglia will be described. Since aberrant signaling is correlated with neurodegenerative disease onset, the relationship between maladapted PI3K-AKT signaling and the development of neurodegenerative disease will also be explored. Finally, studies in which microglial PI3K-AKT signaling has been modulated will be highlighted, as this may prove to be a promising therapeutic approach for the future treatment of a range of neuroinflammatory conditions.
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Affiliation(s)
- Erskine Chu
- Department of Immunology and Pathology, Central Clinical School, Monash University, Level 6, 89 Commercial Road, Melbourne, VIC, 3004, Australia
- Department of Neuroscience, Central Clinical School, Monash University, Level 6, 99 Commercial Road, Melbourne, VIC, 3004, Australia
| | - Richelle Mychasiuk
- Department of Neuroscience, Central Clinical School, Monash University, Level 6, 99 Commercial Road, Melbourne, VIC, 3004, Australia
- Department of Neurology, Alfred Health, Prahran, VIC, 3181, Australia
| | - Margaret L Hibbs
- Department of Immunology and Pathology, Central Clinical School, Monash University, Level 6, 89 Commercial Road, Melbourne, VIC, 3004, Australia.
| | - Bridgette D Semple
- Department of Neuroscience, Central Clinical School, Monash University, Level 6, 99 Commercial Road, Melbourne, VIC, 3004, Australia.
- Department of Neurology, Alfred Health, Prahran, VIC, 3181, Australia.
- Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Parkville, VIC, 3050, Australia.
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50
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Huang W, Lv Q, Xiao Y, Zhong Z, Hu B, Yan S, Yan Y, Zhang J, Shi T, Jiang L, Li W, Lu G. Triggering Receptor Expressed on Myeloid Cells 2 Protects Dopaminergic Neurons by Promoting Autophagy in the Inflammatory Pathogenesis of Parkinson's Disease. Front Neurosci 2021; 15:745815. [PMID: 34867158 PMCID: PMC8641649 DOI: 10.3389/fnins.2021.745815] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 10/12/2021] [Indexed: 12/12/2022] Open
Abstract
Parkinson's disease is a neurodegenerative disorder with an inflammatory response as the core pathogenic mechanism. Previous human genetics findings support the view that the loss of TREM2 function will aggravate neurodegeneration, and TREM2 is one of the most highly expressed receptors in microglia. However, the role of TREM2 in the inflammatory mechanism of PD is not clear. In our study, it was found both in vivo and in vitro that the activation of microglia not only promoted the secretion of inflammatory factors but also decreased the level of TREM2 and inhibited the occurrence of autophagy. In contrast, an increase in the level of TREM2 decreased the expression of inflammatory factors and enhanced the level of autophagy through the p38 MAPK/mTOR pathway. Moreover, increased TREM2 expression significantly decreased the apoptosis of dopaminergic (DA) neurons and improved the motor ability of PD mice. In summary, TREM2 is an important link between the pathogenesis of PD and inflammation. Our study provides a new view for the mechanism of TREM2 in PD and reveals TREM2 as a potential therapeutic target for PD.
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Affiliation(s)
- Wei Huang
- Department of Neurosurgery, The First Affiliated Hospital of Nanchang University, Nanchang, China
- Department of Neurology, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Qiankun Lv
- Department of Neurology, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Yunfei Xiao
- Institute of Translational Medicine, Nanchang University, Nanchang, China
| | - Zhen Zhong
- Department of Neurology, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Binbin Hu
- Department of Neurology, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Si Yan
- Department of Neurology, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Yufang Yan
- Department of Neurology, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Junjun Zhang
- Department of Neurology, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Ting Shi
- Department of Neurology, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Lijuan Jiang
- Department of Neurology, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Wen Li
- Department of Neurology, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Guohui Lu
- Department of Neurosurgery, The First Affiliated Hospital of Nanchang University, Nanchang, China
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