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Liu Y, Chen Y, Gao M, Luo J, Wang Y, Wang Y, Gao Y, Yang L, Wang J, Wang N. Association between glioma and neurodegenerative diseases risk: a two-sample bi-directional Mendelian randomization analysis. Front Neurol 2024; 15:1413015. [PMID: 39015316 PMCID: PMC11250058 DOI: 10.3389/fneur.2024.1413015] [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: 04/06/2024] [Accepted: 06/19/2024] [Indexed: 07/18/2024] Open
Abstract
Background Earlier observational studies have demonstrated a correlation between glioma and the risk of neurodegenerative diseases (NDs), but the causality and direction of their associations remain unclear. The objective of this study was to ascertain the causal link between glioma and NDs using Mendelian randomization (MR) methodology. Methods Genome-wide association study (GWAS) data were used in a two-sample bi-directional MR analysis. From the largest meta-analysis GWAS, encompassing 18,169 controls and 12,488 cases, summary statistics data on gliomas was extracted. Summarized statistics for NDs, including Alzheimer's disease (AD), multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS) and Parkinson's disease (PD) were obtained from the GWAS of European ancestry. Inverse variance weighted (IVW) method was elected as the core MR approach with weighted median (WM) method and MR-Egger method as complementary methods. In addition, sensitivity analyses were performed. A Bonferroni correction was used to correct the results. Results Genetically predicted glioma had been related to decreased risk of AD. Specifically, for all glioma (IVW: OR = 0.93, 95% CI = 0.90-0.96, p = 4.88 × 10-6) and glioblastoma (GBM) (IVW: OR = 0.93, 95% CI = 0.91-0.95, p = 5.11 × 10-9). We also found that genetically predicted all glioma has a suggestive causative association with MS (IVW: OR = 0.90, 95% CI = 0.81-1.00, p = 0.045). There was no evidence of causal association between glioma and ALS or PD. According to the results of reverse MR analysis, no discernible causal connection of NDs was found on glioma. Sensitivity analyses validated the robustness of the above associations. Conclusion We report evidence in support of potential causal associations of different glioma subtypes with AD and MS. More studies are required to uncover the underlying mechanisms of these findings.
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Affiliation(s)
- Yang Liu
- Department of Endocrinology, Affiliated Hospital of Jilin Medical University, Jilin, China
| | - Youqi Chen
- Bethune First Hospital of Jilin University, Changchun, China
| | - Ming Gao
- Bethune First Hospital of Jilin University, Changchun, China
| | - Jia Luo
- Bethune First Hospital of Jilin University, Changchun, China
| | - Yanan Wang
- Bethune First Hospital of Jilin University, Changchun, China
| | - Yihan Wang
- Bethune Third Hospital of Jilin University, Changchun, China
| | - Yu Gao
- Clinical College, The Second Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Laiyu Yang
- Bethune Third Hospital of Jilin University, Changchun, China
| | - Jingning Wang
- Bethune First Hospital of Jilin University, Changchun, China
| | - Ningxin Wang
- Bethune First Hospital of Jilin University, Changchun, China
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2
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Ertel MV, da Silva ABA, de Sousa DF, Dos Santos CJ, da Silva TM, da Silva-Sales MFM, de Oliveira Matos A, Sales-Campos H. Who is who within the universe of TREM-like transcripts (TREML)? Life Sci 2024; 348:122696. [PMID: 38710279 DOI: 10.1016/j.lfs.2024.122696] [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: 11/16/2023] [Revised: 04/29/2024] [Accepted: 05/03/2024] [Indexed: 05/08/2024]
Abstract
The Triggering Receptor Expressed on Myeloid Cells (TREM) family of receptors plays a crucial role in the immune response across various species. Particularly, TREM-1 and TREM-2 have been extensively studied, both in terms of their applications and their expression sites and signaling pathways. However, the same is not observed for the other family members collectively known as TREM-like-transcripts (TREML). The TREML family consists of eight receptors, with TREML1-5 identified in humans and mice, TREML-6 exclusive found in mice, TREML-7 in dogs and horses, and TREML-8 in rabbits and opossums. Despite the limited data available on the TREML members, they have been implicated in different immune and non-immune activities, which have been proposed to display both pro and anti-inflammatory activities, and to influence fundamental biological processes such as coagulation, bone and neurological development. In this review, we have compiled available information regarding the already discovered members of the family and provided foundational framework for understanding the function, localization, and therapeutic potential of all TREML members. Additionally, we hope that this review may shed light on this family of receptors, whose underlying mechanisms are still awaiting elucidation, while emphasizing the need for future studies to explore their functions and potential therapeutic application.
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Affiliation(s)
- Márcia Verônica Ertel
- Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, Goiás, Brazil.
| | | | - Daniel Francisco de Sousa
- Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, Goiás, Brazil.
| | - Cairo José Dos Santos
- Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, Goiás, Brazil.
| | - Tatiane Mendonça da Silva
- Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, Goiás, Brazil.
| | | | - Amanda de Oliveira Matos
- Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, Goiás, Brazil.
| | - Helioswilton Sales-Campos
- Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, Goiás, Brazil.
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3
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Orihashi R, Imamura Y, Mizoguchi Y. Association between sTREM2, an immune biomarker of microglial activation, and frontal lobe function in community-dwelling older adults: a cross-sectional study. J Rural Med 2024; 19:186-191. [PMID: 38975040 PMCID: PMC11222625 DOI: 10.2185/jrm.2024-018] [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: 04/04/2024] [Accepted: 04/30/2024] [Indexed: 07/09/2024] Open
Abstract
Objective: Identifying the peripheral biomarkers related to the prevention or modification of unhealthy mental conditions in older adults is extremely beneficial. This study aimed to evaluate the serum levels of soluble triggering receptor expressed on myeloid cells 2 (sTREM2), a soluble form of an innate immune receptor expressed on microglia, in older adults living in a rural community, and their association with cognitive function. Materials and Methods: This survey was conducted between November 2016 and September 2017 in Kurokawa-cho, Imari, Saga Prefecture, Japan, among people aged ≥65 years. Blood samples were collected from the participants for serum sTREM2 level analysis using a peptide enzyme immunoassay. The participants underwent cognitive function assessments, including the Mini-Mental State Examination, Clinical Dementia Rating, and Frontal Assessment Battery. Therefore, we examined the association between serum sTREM2 levels and cognitive function. Results: Of the 95 participants, 25 were men and 70 were women with a mean age 78.24 ± 3.85 years and 77.96 ± 5.52 years, respectively. Serum sTREM2 levels were negatively associated with Frontal Assessment Battery scores, even after adjusting for age, sex, years of education, and serum high-sensitivity C-reactive protein levels. Conclusion: Serum sTREM2 levels may be associated with frontal lobe function in adults aged ≥65 years.
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Affiliation(s)
- Ryuzo Orihashi
- Institute of Nursing, Faculty of Medicine, Saga University, Japan
- Department of Psychiatry, Faculty of Medicine, Saga University, Japan
| | - Yoshiomi Imamura
- Department of Psychiatry, Faculty of Medicine, Saga University, Japan
| | - Yoshito Mizoguchi
- Department of Psychiatry, Faculty of Medicine, Saga University, Japan
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4
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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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Barry-Carroll L, Gomez-Nicola D. The molecular determinants of microglial developmental dynamics. Nat Rev Neurosci 2024; 25:414-427. [PMID: 38658739 DOI: 10.1038/s41583-024-00813-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/21/2024] [Indexed: 04/26/2024]
Abstract
Microglia constitute the largest population of parenchymal macrophages in the brain and are considered a unique subset of central nervous system glial cells owing to their extra-embryonic origins in the yolk sac. During development, microglial progenitors readily proliferate and eventually colonize the entire brain. In this Review, we highlight the origins of microglial progenitors and their entry routes into the brain and discuss the various molecular and non-molecular determinants of their fate, which may inform their specific functions. Specifically, we explore recently identified mechanisms that regulate microglial colonization of the brain, including the availability of space, and describe how the expansion of highly proliferative microglial progenitors facilitates the occupation of the microglial niche. Finally, we shed light on the factors involved in establishing microglial identity in the brain.
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Affiliation(s)
- Liam Barry-Carroll
- Nutrineuro, UMR 1286 INRAE, Bordeaux University, Bordeaux INP, Bordeaux, France
| | - Diego Gomez-Nicola
- School of Biological Sciences, University of Southampton, Southampton General Hospital, Southampton, UK.
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6
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Meng J, Han L, Xu H, Zhang L, Liu Z, Zhou Y, Zhang X, Luo H, Zhang YW. TREM2 regulates microglial phagocytosis of synapses in innate immune tolerance. Int Immunopharmacol 2024; 127:111445. [PMID: 38147777 DOI: 10.1016/j.intimp.2023.111445] [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: 11/08/2023] [Revised: 12/15/2023] [Accepted: 12/21/2023] [Indexed: 12/28/2023]
Abstract
Increasing evidence indicates that innate immune cells also possess immunological memory. Microglia are brain-resident innate immune cells and execute inflammatory and phagocytic functions upon environmental stimulation, during which processes triggering receptor expressed on myeloid cells 2 (TREM2) plays an important regulatory role. However, although microglia are known to exhibit innate immune memory related to inflammation when subjected to continuous inflammatory stimuli, whether microglia exhibit innate immune memory related to phagocytosis and whether TREM2 participates in innate immune memory of microglia remain unknown. Herein, we treated WT and Trem2 KO mice with peripheral injection of lipopolysaccharides (LPS) to induce microglial activation or microglial immune tolerance. We found that Tnfα and Il-1β expression levels in the hippocampi were significantly elevated after 1xLPS and then dramatically decreased after 4xLPS in both WT and Trem2 KO mice; and their level changes were indistinguishable between WT and Trem2 KO mice. Moreover, 1xLPS significantly promoted microglial phagocytosis of synapses and caused microglial morphology changes resembling activated status in both WT and Trem2 KO mice. However, 4xLPS significantly reduced synapse phagocytosis and largely reversed morphology changes in WT microglia. While 4xLPS had no effect on reducing synapse phagocytosis in Trem2 KO microglia. RNA-seq analysis revealed that TREM2 deficiency reprogrammed complement and phagosome-related transcriptional landscape during immune tolerance. Our results demonstrate that microglia also exhibit immune tolerance related to phagocytosis of synapses and that TREM2 plays a crucial role in this process possibly through regulating complement system and phagosome-related gene expressions.
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Affiliation(s)
- Jian Meng
- Xiamen Key Laboratory of Brain Center, The First Affiliated Hospital of Xiamen University, and Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, Fujian 361102, China.
| | - Linkun Han
- Xiamen Key Laboratory of Brain Center, The First Affiliated Hospital of Xiamen University, and Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, Fujian 361102, China
| | - Hui Xu
- Xiamen Key Laboratory of Brain Center, The First Affiliated Hospital of Xiamen University, and Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, Fujian 361102, China
| | - Lingliang Zhang
- Xiamen Key Laboratory of Brain Center, The First Affiliated Hospital of Xiamen University, and Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, Fujian 361102, China
| | - Zhaoji Liu
- Department of Neurology, Zhongshan Hospital Xiamen University, Xiamen, Fujian 361004, China
| | - Yunqiang Zhou
- Xiamen Key Laboratory of Brain Center, The First Affiliated Hospital of Xiamen University, and Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, Fujian 361102, China
| | - Xian Zhang
- Xiamen Key Laboratory of Brain Center, The First Affiliated Hospital of Xiamen University, and Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, Fujian 361102, China
| | - Hong Luo
- Xiamen Key Laboratory of Brain Center, The First Affiliated Hospital of Xiamen University, and Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, Fujian 361102, China
| | - Yun-Wu Zhang
- Xiamen Key Laboratory of Brain Center, The First Affiliated Hospital of Xiamen University, and Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, Fujian 361102, China.
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7
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Shi J, Wang X, Kang C, Liu J, Ma C, Yang L, Hu J, Zhao N. TREM2 regulates BV2 microglia activation and influences corticosterone-induced neuroinflammation in depressive disorders. Brain Res 2024; 1822:148664. [PMID: 37923002 DOI: 10.1016/j.brainres.2023.148664] [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: 08/02/2023] [Revised: 10/14/2023] [Accepted: 10/30/2023] [Indexed: 11/07/2023]
Abstract
Depressive disorders is a serious mental illness, and its underlying pathological mechanisms remain unclear. The overactivation of microglia and neuroinflammation are thought to play an essential role in the occurrence and development of depressive disorders. TREM2, an immune protein mainly expressed in microglia, is an important part of nerve cells involved in inflammatory response. Corticosterone (CORT) is often referred to as a stress hormone and plays a role in the immune system and stress response. Therefore, this study investigated the role of TREM2 in CORT-induced BV2 cell damage and preliminarily analyzed the effects of TREM2 on JAK2/STAT3 signaling pathway and microglia polarization. The cell model of CORT-induced depression in vitro was established, and the effect of CORT on the activity of BV2 microglia was detected by CCK8. Plasmid transfection was used to overexpress and interfere with TREM2 in BV2 cells cultured by CORT. Western blotting, PCR, and ELISA analyzed the expression of related proteins and inflammatory factors. The results showed that CORT could affect BV2 cell proliferation and TREM2 levels. In the presence of CORT, overexpression of TREM2 decreased the levels of TNF-α, IL-1β, and IL-6 and increased the levels of IL-10. Interference with TREM2 increased the levels of TNF-α, IL-1β, and IL-6 and decreased the levels of IL-10. TREM2 can affect the release of inflammatory factors through the JAK2/STAT3 signaling pathway and regulate the M1/M2 phenotypic transformation of microglia. TREM2 plays a role in regulating CORT-induced inflammatory responses, revealing the influence of TREM2 on the neuroinflammatory pathogenesis of depressive disorders and suggesting that TREM2 may be a new target for the prevention and treatment of depressive disorders.
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Affiliation(s)
- Jingjing Shi
- Department of Psychiatry, The First Affiliated Hospital of Harbin Medical University, 23 Youzheng Street, Nangang District, Harbin, Heilongjiang Province 150001, China
| | - Xiaohong Wang
- Department of Psychiatry, The First Affiliated Hospital of Harbin Medical University, 23 Youzheng Street, Nangang District, Harbin, Heilongjiang Province 150001, China
| | - Chuanyi Kang
- Department of Psychiatry, The First Affiliated Hospital of Harbin Medical University, 23 Youzheng Street, Nangang District, Harbin, Heilongjiang Province 150001, China
| | - Jiacheng Liu
- Department of Psychiatry, The First Affiliated Hospital of Harbin Medical University, 23 Youzheng Street, Nangang District, Harbin, Heilongjiang Province 150001, China
| | - Caina Ma
- Harbin First Specialized Hospital, Heilongjiang Province, China
| | - Liying Yang
- Department of Psychiatry, The First Affiliated Hospital of Harbin Medical University, 23 Youzheng Street, Nangang District, Harbin, Heilongjiang Province 150001, China
| | - Jian Hu
- Department of Psychiatry, The First Affiliated Hospital of Harbin Medical University, 23 Youzheng Street, Nangang District, Harbin, Heilongjiang Province 150001, China.
| | - Na Zhao
- Department of Psychiatry, The First Affiliated Hospital of Harbin Medical University, 23 Youzheng Street, Nangang District, Harbin, Heilongjiang Province 150001, China.
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Zhang X, Chen X, Zhang L, Sun Y, Liang Y, Li H, Zhang Y. Role of trigger receptor 2 expressed on myeloid cells in neuroinflammation-neglected multidimensional regulation of microglia. Neurochem Int 2023; 171:105639. [PMID: 37926352 DOI: 10.1016/j.neuint.2023.105639] [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: 08/21/2023] [Revised: 10/01/2023] [Accepted: 11/02/2023] [Indexed: 11/07/2023]
Abstract
Neuroinflammation is an inflammatory cascade involved in various neurological disorders, including Alzheimer's disease, multiple sclerosis, and other relevant diseases. The triggering receptor expressed on myeloid cells 2 (TREM2) is a transmembrane immune receptor that is primarily expressed by microglia in the central nervous system (CNS). While TREM2 is initially believed to be an anti-inflammatory factor in the CNS, increasing evidence suggests that TREM2 plays a more complex role in balancing neuroinflammation. However, the exact mechanism remains unclear. Notably, TREM2 directly regulates microglia inflammation through various signaling pathways. Additionally, studies have suggested that TREM2 mediates microglial phagocytosis, autophagy, metabolism, and microglia phenotypes, which may be involved in the modulation of neuroinflammation. In this review, we aim to discuss the critical role of TREM2 in several microglia functions and the underlying molecular mechanism the modulatory which further mediate neuroinflammation, and elaborate. Finally, we discuss the potential of TREM2 as a therapeutic target in neuroinflammatory disorders.
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Affiliation(s)
- Xin Zhang
- Department of Respiratory and Critical Care Medicine, Beijing Youan Hospital, Capital Medical University, Beijing, China; Beijing Institute of Hepatology, Beijing Key Laboratory for HIV/AIDS Research, Clinical and Research Center for Infectious Diseases, Beijing Youan Hospital, Capital Medical University, Beijing, China
| | - Xue Chen
- Department of Respiratory and Critical Care Medicine, Beijing Youan Hospital, Capital Medical University, Beijing, China; Beijing Institute of Hepatology, Beijing Key Laboratory for HIV/AIDS Research, Clinical and Research Center for Infectious Diseases, Beijing Youan Hospital, Capital Medical University, Beijing, China
| | - Ling Zhang
- Department of Respiratory and Critical Care Medicine, Beijing Youan Hospital, Capital Medical University, Beijing, China
| | - Yuqing Sun
- Department of Respiratory and Critical Care Medicine, Beijing Youan Hospital, Capital Medical University, Beijing, China
| | - Ying Liang
- Department of Respiratory and Critical Care Medicine, Beijing Youan Hospital, Capital Medical University, Beijing, China
| | - Huan Li
- Department of Cardiology, Beijing Youan Hospital, Capital Medical University, Beijing, China
| | - Yulin Zhang
- Department of Respiratory and Critical Care Medicine, Beijing Youan Hospital, Capital Medical University, Beijing, China; Beijing Institute of Hepatology, Beijing Key Laboratory for HIV/AIDS Research, Clinical and Research Center for Infectious Diseases, Beijing Youan Hospital, Capital Medical University, Beijing, China.
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Zhang J, Wang Y, Zhang Y, Yao J. Genome-wide association study in Alzheimer's disease: a bibliometric and visualization analysis. Front Aging Neurosci 2023; 15:1290657. [PMID: 38094504 PMCID: PMC10716290 DOI: 10.3389/fnagi.2023.1290657] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Accepted: 11/08/2023] [Indexed: 02/23/2024] Open
Abstract
BACKGROUND Thousands of research studies concerning genome-wide association studies (GWAS) in Alzheimer's disease (AD) have been published in the last decades. However, a comprehensive understanding of the current research status and future development trends of GWAS in AD have not been clearly shown. In this study, we tried to gain a systematic overview of GWAS in AD by bibliometric and visualization analysis. METHODS The literature search terms are: ("genome-wide analysis" or "genome-wide association study" or "whole-genome analysis") AND ("Alzheimer's Disease" or "Alzheimer Disease"). Relevant publications were extracted from the Web of Science Core Collection (WoSCC) database. Collected data were further analyzed using VOSviewer, CiteSpace and R package Bibliometrix. The countries, institutions, authors and scholar collaborations were investigated. The co-citation analysis of publications was visualized. In addition, research hotspots and fronts were examined. RESULTS A total of 1,350 publications with 59,818 citations were identified. The number of publications and citations presented a significant rising trend since 2013. The United States was the leading country with an overwhelming number of publications (775) and citations (42,237). The University of Washington and Harvard University were the most prolific institutions with 101 publications each. Bennett DA was the most influential researcher with the highest local H-index. Neurobiology of Aging was the journal with the highest number of publications. Aβ, tau, immunity, microglia and DNA methylation were research hotspots. Disease and causal variants were research fronts. CONCLUSION The most frequently studied AD pathogenesis and research hotspots are (1) Aβ and tau, (2) immunity and microglia, with TREM2 as a potential immunotherapy target, and (3) DNA methylation. The research fronts are (1) looking for genetic similarities between AD and other neurological diseases and syndromes, and (2) searching for causal variants of AD. These hotspots suggest noteworthy directions for future studies on AD pathogenesis and genetics, in which basic research regarding immunity is promising for clinical conversion. The current under-researched directions are (1) GWAS in AD biomarkers based on large sample sizes, (2) studies of causal variants of AD, and (3) GWAS in AD based on non-European populations, which need to be strengthened in the future.
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Affiliation(s)
- Junyao Zhang
- Department of Anesthesiology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yinuo Wang
- Department of Anesthesiology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yingying Zhang
- Department of Anesthesiology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Junyan Yao
- Department of Anesthesiology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Department of Anesthesiology and Critical Care Medicine, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China
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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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11
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Guo X, Chang M, Wang Y, Xing B, Ma W. B7-H3 in Brain Malignancies: Immunology and Immunotherapy. Int J Biol Sci 2023; 19:3762-3780. [PMID: 37564196 PMCID: PMC10411461 DOI: 10.7150/ijbs.85813] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Accepted: 07/13/2023] [Indexed: 08/12/2023] Open
Abstract
The immune checkpoint B7-H3 (CD276), a member of the B7 family with immunoregulatory properties, has been identified recently as a novel target for immunotherapy for refractory blood cancers and solid malignant tumors. While research on B7-H3 in brain malignancies is limited, there is growing interest in exploring its therapeutic potential in this context. B7-H3 plays a crucial role in regulating the functions of immune cells, cancer-associated fibroblasts, and endothelial cells within the tumor microenvironment, contributing to the creation of a pro-tumorigenic milieu. This microenvironment promotes uncontrolled cancer cell proliferation, enhanced metabolism, increased cancer stemness, and resistance to standard treatments. Blocking B7-H3 and terminating its immunosuppressive function is expected to improve anti-tumor immune responses and, in turn, ameliorate the progression of tumors. Results from preclinical or observative studies and early-phase trials targeting B7-H3 have revealed promising anti-tumor efficacy and acceptable toxicity in glioblastoma (GBM), diffuse intrinsic pontine glioma (DIPG), medulloblastoma, neuroblastoma, craniopharyngioma, atypical teratoid/rhabdoid tumor, and brain metastases. Ongoing clinical trials are now investigating the use of CAR-T cell therapy and antibody-drug conjugate therapy, either alone or in combination with standard treatments or other therapeutic approaches, targeting B7-H3 in refractory or recurrent GBMs, DIPGs, neuroblastomas, medulloblastomas, ependymomas, and metastatic brain tumors. These trials hold promise for providing effective treatment options for these challenging intracranial malignancies in both adult and pediatric populations.
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Affiliation(s)
- Xiaopeng Guo
- Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
| | - Mengqi Chang
- Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
- Medical Research Center, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
| | - Yu Wang
- Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
| | - Bing Xing
- Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
| | - Wenbin Ma
- Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
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Sun X, Jin X, Liu X, Wang L, Li L, Yang J, Feng H, Lin Z, Zhan C, Zhang W, Gu C, Hu X, Liu X, Cheng G. Microglia play an important role in PRV infection-induced immune responses of the central nervous system. Virol J 2023; 20:151. [PMID: 37452371 PMCID: PMC10349424 DOI: 10.1186/s12985-023-02118-8] [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: 06/12/2023] [Accepted: 07/07/2023] [Indexed: 07/18/2023] Open
Abstract
Pseudorabies virus (PRV) can infect multiple hosts and lead to fatal encephalitis. There is a significant increase in the number of microglia in the brain of animals infected with PRV. However, whether and how microglia contribute to central nervous system damage in PRV infection remain unknown. In the present study, we elucidated that PRV infection can cause more severe inflammatory cell infiltration, thicker and more numerous vessel sleeve walls, and more severe inflammatory responses in the brains of natural hosts (pigs) than in those of nonnatural hosts (mice). In a mice infection model, activated microglia restricted viral replication in the early stage of infection. Acute neuroinflammation caused by microglia hyperactivation at late-stage of infection. Furthermore, in vitro experiments revealed that microglia restricted viral replication and decreased viral infectivity. This may be associated with the phagocytic ability of microglia because we observed a significant increase in the expression of the membrane receptor TREM2 in microglia, which is closely related to phagocytosis, we observed that depletion of microglia exacerbated neurological symptoms, blood-brain barrier breakdown, and peripheral lymphocyte infiltration. Taken together, we revealed the dual role of microglia in protecting the host and neurons from PRV infection.
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Affiliation(s)
- Xiuxiu Sun
- Division of Veterinary Pathology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Xinxin Jin
- Division of Veterinary Pathology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Xi Liu
- Division of Veterinary Pathology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Lumeng Wang
- Henan Shengming Biotechnology Research, Xinxiang, China
| | - Li Li
- Division of Veterinary Pathology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Junjie Yang
- Division of Veterinary Pathology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Helong Feng
- Division of Veterinary Pathology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Zhengdan Lin
- Division of Veterinary Pathology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Cunlin Zhan
- Division of Veterinary Pathology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Wanpo Zhang
- Division of Veterinary Pathology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Changqin Gu
- Division of Veterinary Pathology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Xueying Hu
- Division of Veterinary Pathology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Xiaoli Liu
- Division of Veterinary Pathology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Guofu Cheng
- Division of Veterinary Pathology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China.
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Melchiorri D, Merlo S, Micallef B, Borg JJ, Dráfi F. Alzheimer's disease and neuroinflammation: will new drugs in clinical trials pave the way to a multi-target therapy? Front Pharmacol 2023; 14:1196413. [PMID: 37332353 PMCID: PMC10272781 DOI: 10.3389/fphar.2023.1196413] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 05/02/2023] [Indexed: 06/20/2023] Open
Abstract
Despite extensive research, no disease-modifying therapeutic option, able to prevent, cure or halt the progression of Alzheimer's disease [AD], is currently available. AD, a devastating neurodegenerative pathology leading to dementia and death, is characterized by two pathological hallmarks, the extracellular deposits of amyloid beta (Aβ) and the intraneuronal deposits of neurofibrillary tangles (NFTs) consisting of altered hyperphosphorylated tau protein. Both have been widely studied and pharmacologically targeted for many years, without significant therapeutic results. In 2022, positive data on two monoclonal antibodies targeting Aβ, donanemab and lecanemab, followed by the 2023 FDA accelerated approval of lecanemab and the publication of the final results of the phase III Clarity AD study, have strengthened the hypothesis of a causal role of Aβ in the pathogenesis of AD. However, the magnitude of the clinical effect elicited by the two drugs is limited, suggesting that additional pathological mechanisms may contribute to the disease. Cumulative studies have shown inflammation as one of the main contributors to the pathogenesis of AD, leading to the recognition of a specific role of neuroinflammation synergic with the Aβ and NFTs cascades. The present review provides an overview of the investigational drugs targeting neuroinflammation that are currently in clinical trials. Moreover, their mechanisms of action, their positioning in the pathological cascade of events that occur in the brain throughout AD disease and their potential benefit/limitation in the therapeutic strategy in AD are discussed and highlighted as well. In addition, the latest patent requests for inflammation-targeting therapeutics to be developed in AD will also be discussed.
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Affiliation(s)
- Daniela Melchiorri
- Department of Physiology and Pharmacology, Sapienza University, Rome, Italy
| | - Sara Merlo
- Department of Biomedical and Biotechnological Sciences, Section of Pharmacology, University of Catania, Catania, Italy
| | | | - John-Joseph Borg
- Malta Medicines Authority, San Ġwann, Malta
- School of Pharmacy, Department of Biology, University of Tor Vergata, Rome, Italy
| | - František Dráfi
- Institute of Experimental Pharmacology and Toxicology, Centre of Experimental Medicine SAS Bratislava, Bratislava, Slovakia
- State Institute for Drug Control, Bratislava, Slovakia
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14
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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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15
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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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16
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La Rosa F, Agostini S, Piancone F, Marventano I, Hernis A, Fenoglio C, Galimberti D, Scarpini E, Saresella M, Clerici M. TREM2 Expression and Amyloid-Beta Phagocytosis in Alzheimer's Disease. Int J Mol Sci 2023; 24:ijms24108626. [PMID: 37239970 DOI: 10.3390/ijms24108626] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 04/28/2023] [Accepted: 05/02/2023] [Indexed: 05/28/2023] Open
Abstract
Alzheimer's Disease is the most common form of dementia; its key pathological findings include the deposition of extracellular-neurotoxic-plaques composed of amyloid-beta (Ab). AD-pathogenesis involves mechanisms that operate outside the brain, and new researches indicate that peripheral inflammation is an early event in the disease. Herein, we focus on a receptor known as triggering-receptor-expressed-on-myeloid-cells2 (TREM2), which promotes the optimal immune cells function required to attenuate AD-progression and is, therefore, a potential target as peripheral diagnostic and prognostic-biomarker for Alzheimer's Disease. The objective of this exploratory study was to analyze: (1) soluble-TREM2 (sTREM2) plasma and cerebrospinal fluid concentration, (2) TREM2-mRNA, (3) the percentage of TREM2-expressing monocytes, and (4) the concentration of miR-146a-5p and miR-34a-5p suspected to influence TREM2 transcription. Experiments were performed on PBMC collected by 15AD patients and 12age-matched healthy controls that were unstimulated or treated in inflammatory (LPS) conditions and Ab42 for 24 h; Aβ42-phagocytosis was also analyzed by AMNIS FlowSight. Results although preliminary, due to limitations by the small sample-size, showed that in AD compared to HC: TREM2 expressing monocytes were reduced, plasma sTREM2 concentration and TREM2-mRNA were significantly upregulated and Ab42-phagocytosis was diminished (for all p < 0.05). miR-34a-5p expression was reduced (p = 0.02) as well in PBMC of AD, and miR-146 was only observed in AD cells (p = 0.0001).
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Affiliation(s)
| | | | | | | | - Ambra Hernis
- IRCCS Fondazione Don Carlo Gnocchi, 20147 Milan, Italy
| | - Chiara Fenoglio
- Department of Pathophysiology and Transplantation, University of Milan, 20100 Milan, Italy
| | - Daniela Galimberti
- Fondazione Ca' Granda, IRCCS Ospedale Maggiore Policlinico, 20122 Milan, Italy
- Department of Biomedical, Surgical and Dental Sciences, University of Milan, 20100 Milan, Italy
| | - Elio Scarpini
- Fondazione Ca' Granda, IRCCS Ospedale Maggiore Policlinico, 20122 Milan, Italy
| | | | - Mario Clerici
- IRCCS Fondazione Don Carlo Gnocchi, 20147 Milan, Italy
- Department of Pathophysiology and Transplantation, University of Milan, 20100 Milan, Italy
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Chiarini A, Gui L, Viviani C, Armato U, Dal Prà I. NLRP3 Inflammasome’s Activation in Acute and Chronic Brain Diseases—An Update on Pathogenetic Mechanisms and Therapeutic Perspectives with Respect to Other Inflammasomes. Biomedicines 2023; 11:biomedicines11040999. [PMID: 37189617 DOI: 10.3390/biomedicines11040999] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 03/16/2023] [Accepted: 03/17/2023] [Indexed: 03/29/2023] Open
Abstract
Increasingly prevalent acute and chronic human brain diseases are scourges for the elderly. Besides the lack of therapies, these ailments share a neuroinflammation that is triggered/sustained by different innate immunity-related protein oligomers called inflammasomes. Relevant neuroinflammation players such as microglia/monocytes typically exhibit a strong NLRP3 inflammasome activation. Hence the idea that NLRP3 suppression might solve neurodegenerative ailments. Here we review the recent Literature about this topic. First, we update conditions and mechanisms, including RNAs, extracellular vesicles/exosomes, endogenous compounds, and ethnic/pharmacological agents/extracts regulating NLRP3 function. Second, we pinpoint NLRP3-activating mechanisms and known NLRP3 inhibition effects in acute (ischemia, stroke, hemorrhage), chronic (Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, MS, ALS), and virus-induced (Zika, SARS-CoV-2, and others) human brain diseases. The available data show that (i) disease-specific divergent mechanisms activate the (mainly animal) brains NLRP3; (ii) no evidence proves that NLRP3 inhibition modifies human brain diseases (yet ad hoc trials are ongoing); and (iii) no findings exclude that concurrently activated other-than-NLRP3 inflammasomes might functionally replace the inhibited NLRP3. Finally, we highlight that among the causes of the persistent lack of therapies are the species difference problem in disease models and a preference for symptomatic over etiologic therapeutic approaches. Therefore, we posit that human neural cell-based disease models could drive etiological, pathogenetic, and therapeutic advances, including NLRP3’s and other inflammasomes’ regulation, while minimizing failure risks in candidate drug trials.
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18
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Huang Z. A Function of Amyloid-β in Mediating Activity-Dependent Axon/Synapse Competition May Unify Its Roles in Brain Physiology and Pathology. J Alzheimers Dis 2023; 92:29-57. [PMID: 36710681 PMCID: PMC10023438 DOI: 10.3233/jad-221042] [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: 01/28/2023]
Abstract
Amyloid-β protein precursor (AβPP) gives rise to amyloid-β (Aβ), a peptide at the center of Alzheimer's disease (AD). AβPP, however, is also an ancient molecule dating back in evolution to some of the earliest forms of metazoans. This suggests a possible ancestral function that may have been obscured by those that evolve later. Based on literature from the functions of Aβ/AβPP in nervous system development, plasticity, and disease, to those of anti-microbial peptides (AMPs) in bacterial competition as well as mechanisms of cell competition uncovered first by Drosophila genetics, I propose that Aβ/AβPP may be part of an ancient mechanism employed in cell competition, which is subsequently co-opted during evolution for the regulation of activity-dependent neural circuit development and plasticity. This hypothesis is supported by foremost the high similarities of Aβ to AMPs, both of which possess unique, opposite (i.e., trophic versus toxic) activities as monomers and oligomers. A large body of data further suggests that the different Aβ oligomeric isoforms may serve as the protective and punishment signals long predicted to mediate activity-dependent axonal/synaptic competition in the developing nervous system and that the imbalance in their opposite regulation of innate immune and glial cells in the brain may ultimately underpin AD pathogenesis. This hypothesis can not only explain the diverse roles observed of Aβ and AβPP family molecules, but also provide a conceptual framework that can unify current hypotheses on AD. Furthermore, it may explain major clinical observations not accounted for and identify approaches for overcoming shortfalls in AD animal modeling.
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Affiliation(s)
- Zhen Huang
- Departments of Neuroscience and Neurology, University of Wisconsin-Madison, Madison, WI, USA
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19
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Zhang YD, Jiang T, Wang SY, Fu XX, Duan R, Wei B, Cao HM, Yan E, Chen SY. The Alzheimer’s disease-associated gene TREML2 modulates inflammation by regulating microglia polarization and NLRP3 inflammasome activation. Neural Regen Res 2023; 18:434-438. [PMID: 35900442 PMCID: PMC9396521 DOI: 10.4103/1673-5374.346468] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Triggering receptor expressed on myeloid cells-like 2 (TREML2) is a newly identified susceptibility gene for Alzheimer’s disease (AD). It encodes a microglial inflammation-associated receptor. To date, the potential role of microglial TREML2 in neuroinflammation in the context of AD remains unclear. In this study, APP/PS1 mice were used to investigate the dynamic changes of TREML2 levels in brain during AD progression. In addition, lipopolysaccharide (LPS) stimulation of primary microglia as well as a lentivirus-mediated TREML2 overexpression and knockdown were employed to explore the role of TREML2 in neuroinflammation in the context of AD. Our results show that TREML2 levels gradually increased in the brains of APP/PS1 mice during disease progression. LPS stimulation of primary microglia led to the release of inflammatory cytokines including interleukin-1β, interleukin-6, and tumor necrosis factor-α in the culture medium. The LPS-induced microglial release of inflammatory cytokines was enhanced by TREML2 overexpression and was attenuated by TREML2 knockdown. LPS increased the levels of microglial M1-type polarization marker inducible nitric oxide synthase. This effect was enhanced by TREML2 overexpression and ameliorated by TREML2 knockdown. Furthermore, the levels of microglial M2-type polarization markers CD206 and ARG1 in the primary microglia were reduced by TREML2 overexpression and elevated by TREML2 knockdown. LPS stimulation increased the levels of NLRP3 in primary microglia. The LPS-induced increase in NLRP3 was further elevated by TREML2 overexpression and alleviated by TREML2 knockdown. In summary, this study provides the first evidence that TREML2 modulates inflammation by regulating microglial polarization and NLRP3 inflammasome activation. These findings reveal the mechanisms by which TREML2 regulates microglial inflammation and suggest that TREML2 inhibition may represent a novel therapeutic strategy for AD.
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20
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Li JQ, Zhong XL, Song JH, Chi S, Xie AM, Tan L, Yu JT. Associations Between TREML2 Gene Variants and Alzheimer's Disease: Biomarkers, Neuroimage, and Cognition. J Alzheimers Dis 2023; 96:1555-1563. [PMID: 37980675 DOI: 10.3233/jad-230936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2023]
Abstract
BACKGROUND Recent genetic research identified a protective factor against late-onset Alzheimer's disease (AD) in Caucasians, a variant called rs3747742-C in the TREML2 gene. However, the roles of other TREML2 variants in AD have not been fully explored. OBJECTIVE We conducted a focused analysis of 16 TREML2 variants, examining their connection to AD by studying their correlation with cerebrospinal fluid (CSF) proteins, neuroimage, and cognition in the Alzheimer's Disease Neuroimaging Initiative database (ADNI). METHODS A multiple linear regression model was utilized to estimate potential associations between TREML2 genotypes and various endophenotypes in the entire ADNI sample at baseline, with age, gender, years of education, and APOE ɛ4 status included as covariates. To examine changes in clinical outcomes over time, linear mixed-effects models were employed. RESULTS We found that the SNP rs17328707-A was associated with higher ADNI-VS scores, smaller ventricles, and larger middle temporal volume at baseline. The SNP rs6915083-G was linked to lower CSF t-tau and p-tau levels, and higher CSF Aβ levels. The SNP rs9394766-G was associated with a smaller hippocampus and larger ventricles at baseline. In longitudinal cohorts, the rs6915083-G SNP was associated with changes in ADNI-MEM and ADNI-EF scores, as well as the rate of hippocampal and middle temporal atrophy. CONCLUSION Our findings reveal that TREML2 gene variants have different effects on AD. Two variants are protective, while one may be a risk factor. This enhances our understanding of AD genetics and could guide future research and personalized treatments.
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Affiliation(s)
- Jie-Qiong Li
- Department of Neurology, the Affiliated Hospital of Qingdao University, Qingdao, Shandong, China
| | - Xiao-Ling Zhong
- Department of Neurology, Affiliated Qingdao Central Hospital of Qingdao University, Qingdao Cancer Hospital, Qingdao, China
| | - Jing-Hui Song
- Department of Neurology, the Affiliated Hospital of Qingdao University, Qingdao, Shandong, China
| | - Song Chi
- Department of Neurology, the Affiliated Hospital of Qingdao University, Qingdao, Shandong, China
| | - An-Mu Xie
- Department of Neurology, the Affiliated Hospital of Qingdao University, Qingdao, Shandong, China
| | - Lan Tan
- Department of Neurology, Qingdao Municipal Hospital, Qingdao University, Qingdao, Shandong, China
| | - Jin-Tai Yu
- Department of Neurology, Qingdao Municipal Hospital, Qingdao University, Qingdao, Shandong, China
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21
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Wang C, Zong S, Cui X, Wang X, Wu S, Wang L, Liu Y, Lu Z. The effects of microglia-associated neuroinflammation on Alzheimer's disease. Front Immunol 2023; 14:1117172. [PMID: 36911732 PMCID: PMC9992739 DOI: 10.3389/fimmu.2023.1117172] [Citation(s) in RCA: 35] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Accepted: 02/10/2023] [Indexed: 02/24/2023] Open
Abstract
Alzheimer's disease (AD) is defined as a severe chronic degenerative neurological disease in human. The pathogenic mechanism of AD has been convincingly elucidated by the "amyloid cascade hypothesis" with the main focus of the pathological accretion of β-amyloid (Aβ) peptides outside the cell. However, increasing evidence suggests that this hypothesis is weak in explaining the pathogenesis of AD. Neuroinflammation is crucial in the development of AD, which is proven by the elevated levels of inflammatory markers and the identification of AD risk genes relevant to the innate immune function. Here, we summarize the effects of microglia-mediated neuroinflammation on AD, focusing on the temporal and spatial changes in microglial phenotype, the interactions among microglia, Aβ, tau, and neurons, and the prospects and recent advances in neuroinflammation as a diagnostic and therapeutic target of AD.
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Affiliation(s)
- Cuicui Wang
- Department of Clinical Laboratory Medicine, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, China
| | - Shuai Zong
- Department of Clinical Laboratory Medicine, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, China
| | - Xiaolin Cui
- School of Medicine, Shandong University, Jinan, Shandong, China
| | - Xueying Wang
- Department of Clinical Laboratory Medicine, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, China
| | - Shuang Wu
- School of Medicine, Shandong University, Jinan, Shandong, China
| | - Le Wang
- Department of Clinical Laboratory Medicine, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, China
| | - Yingchao Liu
- Department of Clinical Laboratory Medicine, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, China
| | - Zhiming Lu
- Department of Clinical Laboratory Medicine, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, China
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22
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Kühn AL, Frenzel S, Teumer A, Wittfeld K, Garvert L, Weihs A, Homuth G, Prokisch H, Bülow R, Nauck M, Völker U, Völzke H, Grabe HJ, Van der Auwera S. TREML2 Gene Expression and Its Missense Variant rs3747742 Associate with White Matter Hyperintensity Volume and Alzheimer's Disease-Related Brain Atrophy in the General Population. Int J Mol Sci 2022; 23:ijms232213764. [PMID: 36430248 PMCID: PMC9692564 DOI: 10.3390/ijms232213764] [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: 10/13/2022] [Revised: 11/02/2022] [Accepted: 11/04/2022] [Indexed: 11/12/2022] Open
Abstract
Although the common pathology of Alzheimer's disease (AD) and white matter hyperintensities (WMH) is disputed, the gene TREML2 has been implicated in both conditions: its whole-blood gene expression was associated with WMH volume and its missense variant rs3747742 with AD risk. We re-examined those associations within one comprehensive dataset of the general population, additionally searched for cross-relations and illuminated the role of the apolipoprotein E (APOE) ε4 status in the associations. For our linear regression and linear mixed effect models, we used 1949 participants from the Study of Health in Pomerania (Germany). AD was assessed using a continuous pre-symptomatic MRI-based score evaluating a participant's AD-related brain atrophy. In our study, increased whole-blood TREML2 gene expression was significantly associated with reduced WMH volume but not with the AD score. Conversely, rs3747742-C was significantly associated with a reduced AD score but not with WMH volume. The APOE status did not influence the associations. In sum, TREML2 robustly associated with WMH volume and AD-related brain atrophy on different molecular levels. Our results thus underpin TREML2's role in neurodegeneration, might point to its involvement in AD and WMH via different biological mechanisms, and highlight TREML2 as a worthwhile target for disentangling the two pathologies.
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Affiliation(s)
- Annemarie Luise Kühn
- Department of Psychiatry and Psychotherapy, University Medicine Greifswald, 17475 Greifswald, Germany
- Correspondence: (A.L.K.); (S.V.d.A.)
| | - Stefan Frenzel
- Department of Psychiatry and Psychotherapy, University Medicine Greifswald, 17475 Greifswald, Germany
| | - Alexander Teumer
- Institute for Community Medicine, University Medicine Greifswald, 17475 Greifswald, Germany
| | - Katharina Wittfeld
- Department of Psychiatry and Psychotherapy, University Medicine Greifswald, 17475 Greifswald, Germany
- German Center for Neurodegenerative Diseases (DZNE), Site Rostock/Greifswald, 17489 Greifswald, Germany
| | - Linda Garvert
- Department of Psychiatry and Psychotherapy, University Medicine Greifswald, 17475 Greifswald, Germany
| | - Antoine Weihs
- Department of Psychiatry and Psychotherapy, University Medicine Greifswald, 17475 Greifswald, Germany
| | - Georg Homuth
- Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald, 17475 Greifswald, Germany
| | - Holger Prokisch
- Institute of Human Genetics, Technical University Munich, 81675 Munich, Germany
- Institute of Neurogenomics, Helmholtz Zentrum München-German Research Center for Environmental Health, 85764 Neuherberg, Germany
| | - Robin Bülow
- Institute of Diagnostic Radiology and Neuroradiology, University Medicine Greifswald, 17475 Greifswald, Germany
| | - Matthias Nauck
- Institute of Clinical Chemistry and Laboratory Medicine, University Medicine Greifswald, 17475 Greifswald, Germany
- German Centre for Cardiovascular Research (DZHK), Partner Site Greifswald, 17475 Greifswald, Germany
| | - Uwe Völker
- Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald, 17475 Greifswald, Germany
- German Centre for Cardiovascular Research (DZHK), Partner Site Greifswald, 17475 Greifswald, Germany
| | - Henry Völzke
- Institute for Community Medicine, University Medicine Greifswald, 17475 Greifswald, Germany
- German Centre for Cardiovascular Research (DZHK), Partner Site Greifswald, 17475 Greifswald, Germany
| | - Hans Jörgen Grabe
- Department of Psychiatry and Psychotherapy, University Medicine Greifswald, 17475 Greifswald, Germany
- German Center for Neurodegenerative Diseases (DZNE), Site Rostock/Greifswald, 17489 Greifswald, Germany
| | - Sandra Van der Auwera
- Department of Psychiatry and Psychotherapy, University Medicine Greifswald, 17475 Greifswald, Germany
- German Center for Neurodegenerative Diseases (DZNE), Site Rostock/Greifswald, 17489 Greifswald, Germany
- Correspondence: (A.L.K.); (S.V.d.A.)
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Zhao B, Li H, Xia Y, Wang Y, Wang Y, Shi Y, Xing H, Qu T, Wang Y, Ma W. Immune checkpoint of B7-H3 in cancer: from immunology to clinical immunotherapy. J Hematol Oncol 2022; 15:153. [PMID: 36284349 PMCID: PMC9597993 DOI: 10.1186/s13045-022-01364-7] [Citation(s) in RCA: 53] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2022] [Accepted: 09/30/2022] [Indexed: 11/28/2022] Open
Abstract
Immunotherapy for cancer is a rapidly developing treatment that modifies the immune system and enhances the antitumor immune response. B7-H3 (CD276), a member of the B7 family that plays an immunoregulatory role in the T cell response, has been highlighted as a novel potential target for cancer immunotherapy. B7-H3 has been shown to play an inhibitory role in T cell activation and proliferation, participate in tumor immune evasion and influence both the immune response and tumor behavior through different signaling pathways. B7-H3 expression has been found to be aberrantly upregulated in many different cancer types, and an association between B7-H3 expression and poor prognosis has been established. Immunotherapy targeting B7-H3 through different approaches has been developing rapidly, and many ongoing clinical trials are exploring the safety and efficacy profiles of these therapies in cancer. In this review, we summarize the emerging research on the function and underlying pathways of B7-H3, the expression and roles of B7-H3 in different cancer types, and the advances in B7-H3-targeted therapy. Considering different tumor microenvironment characteristics and results from preclinical models to clinical practice, the research indicates that B7-H3 is a promising target for future immunotherapy, which might eventually contribute to an improvement in cancer immunotherapy that will benefit patients.
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Affiliation(s)
- Binghao Zhao
- grid.506261.60000 0001 0706 7839Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100730 People’s Republic of China ,grid.506261.60000 0001 0706 7839State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, People’s Republic of China
| | - Huanzhang Li
- grid.506261.60000 0001 0706 7839Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100730 People’s Republic of China ,grid.506261.60000 0001 0706 7839State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, People’s Republic of China
| | - Yu Xia
- grid.506261.60000 0001 0706 7839Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100730 People’s Republic of China ,grid.506261.60000 0001 0706 7839State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, People’s Republic of China
| | - Yaning Wang
- grid.506261.60000 0001 0706 7839Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100730 People’s Republic of China ,grid.506261.60000 0001 0706 7839State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, People’s Republic of China
| | - Yuekun Wang
- grid.506261.60000 0001 0706 7839Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100730 People’s Republic of China ,grid.506261.60000 0001 0706 7839State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, People’s Republic of China
| | - Yixin Shi
- grid.506261.60000 0001 0706 7839Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100730 People’s Republic of China ,grid.506261.60000 0001 0706 7839State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, People’s Republic of China
| | - Hao Xing
- grid.506261.60000 0001 0706 7839Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100730 People’s Republic of China ,grid.506261.60000 0001 0706 7839State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, People’s Republic of China
| | - Tian Qu
- grid.506261.60000 0001 0706 7839Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100730 People’s Republic of China ,grid.506261.60000 0001 0706 7839State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, People’s Republic of China
| | - Yu Wang
- grid.506261.60000 0001 0706 7839Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100730 People’s Republic of China ,grid.506261.60000 0001 0706 7839State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, People’s Republic of China
| | - Wenbin Ma
- grid.506261.60000 0001 0706 7839Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100730 People’s Republic of China ,grid.506261.60000 0001 0706 7839State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, People’s Republic of China
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24
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Liu S, Cao X, Wu Z, Deng S, Fu H, Wang Y, Liu F. TREM2 improves neurological dysfunction and attenuates neuroinflammation, TLR signaling and neuronal apoptosis in the acute phase of intracerebral hemorrhage. Front Aging Neurosci 2022; 14:967825. [PMID: 36353688 PMCID: PMC9637852 DOI: 10.3389/fnagi.2022.967825] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 09/30/2022] [Indexed: 12/02/2022] Open
Abstract
Neuroinflammation contributes to secondary brain injury following intracerebral hemorrhage (ICH). Triggering receptor expressed on myeloid cells 2 (TREM2) confers strong neuroprotective effect by suppressing neuroinflammatory response in experimental ischemic stroke. This study aimed to clarify the neuroprotective role of TREM2 and potential underlying mechanism in a mouse model of ICH and in vitro. Adeno-associated virus (AAV) and green fluorescent protein-lentivirus (GFP-LV) strategies were employed to enhance TREM2 expression in the C57/BL6 mice and BV2 cells, respectively. The adult male C57/BL6 mice were subjected to ICH by administration of collagenase-IV in 1 month after the AAV particles injection. An in vitro ICH model was performed with oxygen hemoglobin in BV2 cells. Toll-like receptor 4 (TLR4) antagonist TAK242 was applied at 6 h following ICH. Neurological function, TREM2, pro-inflammatory cytokines, brain water content and Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining were evaluated at 24 h following ICH. TLR4, NF-κB and mitogen-activated protein kinases (MAPK) signaling pathways were also determined by Western blot analysis at the same time point. The levels of TREM2 were increased at 12 h, peaked at 24 h and recovered on 7d following ICH. TREM2 overexpression ameliorated ICH induced neurological dysfunction, inhibited neuroinflammation, and attenuated apoptosis and brain edema. Further mechanistic study revealed that TREM2 overexpression inhibited TLR4 activation and NF-κB and MAPK signaling pathways. ICH increased the percentage of TUNEL-positive cells, which was markedly decreased by TREM2 overexpression. A similar improvement was also observed by the administration of TAK242 following ICH. TREM2 improves neurological dysfunction and attenuates neuroinflammation and neuronal apoptosis in the acute phase of ICH, which is, at least in part, mediated by negatively regulating TLR4 signaling pathway. These findings highlight TREM2 as a potential target for early brain injury following ICH.
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Affiliation(s)
- Sidan Liu
- Department of Anesthesiology, the First Hospital of China Medical University, Shenyang, China
| | - Xuezhao Cao
- Department of Anesthesiology, the First Hospital of China Medical University, Shenyang, China
| | - Zhe Wu
- Department of Neurology, the First Hospital of China Medical University, Shenyang, China
| | - Shumin Deng
- Department of Neurology, the First Hospital of China Medical University, Shenyang, China
| | - Hefei Fu
- Department of Neurology, the First Hospital of China Medical University, Shenyang, China
| | - Yanzhe Wang
- Department of Neurology, the First Hospital of China Medical University, Shenyang, China
| | - Fang Liu
- Department of Neurology, the First Hospital of China Medical University, Shenyang, China
- *Correspondence: Fang Liu,
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25
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Dash R, Munni YA, Mitra S, Choi HJ, Jahan SI, Chowdhury A, Jang TJ, Moon IS. Dynamic insights into the effects of nonsynonymous polymorphisms (nsSNPs) on loss of TREM2 function. Sci Rep 2022; 12:9378. [PMID: 35672339 PMCID: PMC9174165 DOI: 10.1038/s41598-022-13120-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Accepted: 05/16/2022] [Indexed: 11/09/2022] Open
Abstract
Single nucleotide variations in Triggering Receptor Expressed on Myeloid Cells 2 (TREM2) are associated with many neurodegenerative diseases, including Nasu-Hakola disease (NHD), frontotemporal dementia (FTD), and late-onset Alzheimer's disease because they disrupt ligand binding to the extracellular domain of TREM2. However, the effects of nonsynonymous single nucleotide polymorphisms (nsSNPs) in TREM2 on disease progression remain unknown. In this study, we identified several high-risk nsSNPs in the TREM2 gene using various deleterious SNP predicting algorithms and analyzed their destabilizing effects on the ligand recognizing region of the TREM2 immunoglobulin (Ig) domain by molecular dynamics (MD) simulation. Cumulative prediction by all tools employed suggested the three most deleterious nsSNPs involved in loss of TREM2 function are rs549402254 (W50S), rs749358844 (R52C), and rs1409131974 (D104G). MD simulation showed that these three variants cause substantial structural alterations and conformational remodeling of the apical loops of the TREM2 Ig domain, which is responsible for ligand recognition. Detailed analysis revealed that these variants substantially increased distances between apical loops and induced conformation remodeling by changing inter-loop nonbonded contacts. Moreover, all nsSNPs changed the electrostatic potentials near the putative ligand-interacting region (PLIR), which suggested they might reduce specificity or loss of binding affinity for TREM2 ligands. Overall, this study identifies three potential high-risk nsSNPs in the TREM2 gene. We propose further studies on the molecular mechanisms responsible for loss of TREM2 function and the associations between TREM2 nsSNPs and neurodegenerative diseases.
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Affiliation(s)
- Raju Dash
- Department of Anatomy, Dongguk University College of Medicine, Gyeongju, 38066, Republic of Korea
| | - Yeasmin Akter Munni
- Department of Anatomy, Dongguk University College of Medicine, Gyeongju, 38066, Republic of Korea
| | - Sarmistha Mitra
- Department of Anatomy, Dongguk University College of Medicine, Gyeongju, 38066, Republic of Korea
| | - Ho Jin Choi
- Department of Anatomy, Dongguk University College of Medicine, Gyeongju, 38066, Republic of Korea
| | - Sultana Israt Jahan
- Department of Biotechnology and Genetic Engineering, Noakhali Science and Technology University, Noakhali, 3814, Bangladesh
| | - Apusi Chowdhury
- Department of Pharmaceutical Science, North-South University, Dhaka, 1229, Bangladesh
| | - Tae Jung Jang
- Department of Pathology, Dongguk University College of Medicine, Gyeongju, 38066, Republic of Korea
| | - Il Soo Moon
- Department of Anatomy, Dongguk University College of Medicine, Gyeongju, 38066, Republic of Korea.
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26
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Li RY, Qin Q, Yang HC, Wang YY, Mi YX, Yin YS, Wang M, Yu CJ, Tang Y. TREM2 in the pathogenesis of AD: a lipid metabolism regulator and potential metabolic therapeutic target. Mol Neurodegener 2022; 17:40. [PMID: 35658903 PMCID: PMC9166437 DOI: 10.1186/s13024-022-00542-y] [Citation(s) in RCA: 43] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Accepted: 05/09/2022] [Indexed: 12/13/2022] Open
Abstract
Triggering receptor expressed on myeloid cells 2 (TREM2) is a single-pass transmembrane immune receptor that is mainly expressed on microglia in the brain and macrophages in the periphery. Recent studies have identified TREM2 as a risk factor for Alzheimer’s disease (AD). Increasing evidence has shown that TREM2 can affect lipid metabolism both in the central nervous system (CNS) and in the periphery. In the CNS, TREM2 affects the metabolism of cholesterol, myelin, and phospholipids and promotes the transition of microglia into a disease-associated phenotype. In the periphery, TREM2 influences lipid metabolism by regulating the onset and progression of obesity and its complications, such as hypercholesterolemia, atherosclerosis, and nonalcoholic fatty liver disease. All these altered lipid metabolism processes could influence the pathogenesis of AD through several means, including affecting inflammation, insulin resistance, and AD pathologies. Herein, we will discuss a potential pathway that TREM2 mediates lipid metabolism to influence the pathogenesis of AD in both the CNS and periphery. Moreover, we discuss the possibility that TREM2 may be a key factor that links central and peripheral lipid metabolism under disease conditions, including AD. This link may be due to impacts on the integrity of the blood–brain barrier, and we introduce potential pathways by which TREM2 affects the blood–brain barrier. Moreover, we discuss the role of lipids in TREM2-associated treatments for AD. We propose some potential therapies targeting TREM2 and discuss the prospect and limitations of these therapies.
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Affiliation(s)
- Rui-Yang Li
- Innovation Center for Neurological Disorders, Department of Neurology, Xuanwu Hospital, Capital Medical University, National Center for Neurological Disorders, Beijing, China
| | - Qi Qin
- Innovation Center for Neurological Disorders, Department of Neurology, Xuanwu Hospital, Capital Medical University, National Center for Neurological Disorders, Beijing, China
| | - Han-Chen Yang
- Innovation Center for Neurological Disorders, Department of Neurology, Xuanwu Hospital, Capital Medical University, National Center for Neurological Disorders, Beijing, China
| | - Ying-Ying Wang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Ying-Xin Mi
- Innovation Center for Neurological Disorders, Department of Neurology, Xuanwu Hospital, Capital Medical University, National Center for Neurological Disorders, Beijing, China
| | - Yun-Si Yin
- Innovation Center for Neurological Disorders, Department of Neurology, Xuanwu Hospital, Capital Medical University, National Center for Neurological Disorders, Beijing, China
| | - Meng Wang
- Innovation Center for Neurological Disorders, Department of Neurology, Xuanwu Hospital, Capital Medical University, National Center for Neurological Disorders, Beijing, China
| | - Chao-Ji Yu
- Innovation Center for Neurological Disorders, Department of Neurology, Xuanwu Hospital, Capital Medical University, National Center for Neurological Disorders, Beijing, China
| | - Yi Tang
- Innovation Center for Neurological Disorders, Department of Neurology, Xuanwu Hospital, Capital Medical University, National Center for Neurological Disorders, Beijing, China.
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27
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Ma WY, Wang SS, Wu QL, Zhou X, Chu SF, Chen NH. The versatile role of TREM2 in regulating of microglia fate in the ischemic stroke. Int Immunopharmacol 2022; 109:108733. [PMID: 35525233 DOI: 10.1016/j.intimp.2022.108733] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Revised: 03/07/2022] [Accepted: 03/22/2022] [Indexed: 12/15/2022]
Abstract
Microglia are the earliest activated and the longest lasting immune cells after stroke, and they participate in almost all the pathological reactions after stroke. However, their regulatory mechanism has not been fully elucidated. Triggering receptor expressed on myeloid cells-2 (TREM2) is a cell surface receptor that is mainly expressed in microglia of the central nervous system. The receptor plays an important role in regulating microglia energy metabolism and phenotypic transformation. At present, TREM2 has been developed as a potential target for AD, coronary atherosclerosis and other diseases. However, TREM2 does not provide a systematic summary of the functional transformation and intrinsic molecular mechanisms of microglia after stroke. In this paper, we have summarized the functional changes of TREM2 in microglia after stroke in recent years, and found that TREM2 has important effects on energy metabolism, phagocytosis and anti-inflammatory function of microglia after stroke, suggesting that TREM2 is a potential therapeutic target for the treatment of stroke.
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Affiliation(s)
- Wen-Yu Ma
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou 510405, China
| | - Sha-Sha Wang
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou 510405, China
| | - Qing-Lin Wu
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou 510405, China
| | - Xin Zhou
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medical & Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Shi-Feng Chu
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medical & Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China.
| | - Nai-Hong Chen
- Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou 510405, China; State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medical & Neuroscience Center, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China.
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28
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Zhao JF, Ren T, Li XY, Guo TL, Liu CH, Wang X. Research Progress on the Role of Microglia Membrane Proteins or Receptors in Neuroinflammation and Degeneration. Front Cell Neurosci 2022; 16:831977. [PMID: 35281298 PMCID: PMC8913711 DOI: 10.3389/fncel.2022.831977] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 01/26/2022] [Indexed: 01/01/2023] Open
Abstract
Microglia are intrinsic immune cells of the central nervous system and play a dual role (pro-inflammatory and anti-inflammatory) in the homeostasis of the nervous system. Neuroinflammation mediated by microglia serves as an important stage of ischemic hypoxic brain injury, cerebral hemorrhage disease, neurodegeneration and neurotumor of the nervous system and is present through the whole course of these diseases. Microglial membrane protein or receptor is the basis of mediating microglia to play the inflammatory role and they have been found to be upregulated by recognizing associated ligands or sensing changes in the nervous system microenvironment. They can then allosterically activate the downstream signal transduction and produce a series of complex cascade reactions that can activate microglia, promote microglia chemotactic migration and stimulate the release of proinflammatory factor such as TNF-α, IL-β to effectively damage the nervous system and cause apoptosis of neurons. In this paper, several representative membrane proteins or receptors present on the surface of microglia are systematically reviewed and information about their structures, functions and specific roles in one or more neurological diseases. And on this basis, some prospects for the treatment of novel coronavirus neurological complications are presented.
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Affiliation(s)
- Jun-Feng Zhao
- Department of Neurosurgery, Affiliated Dalian No. 3 People’s Hospital, Dalian Medical University, Dalian, China
| | - Tong Ren
- Department of Neurosurgery, Affiliated Dalian No. 3 People’s Hospital, Dalian Medical University, Dalian, China
| | - Xiang-Yu Li
- Department of Neurosurgery, Affiliated Dalian No. 3 People’s Hospital, Dalian Medical University, Dalian, China
| | - Tian-Lin Guo
- Department of Neurosurgery, Affiliated Dalian No. 3 People’s Hospital, Dalian Medical University, Dalian, China
| | - Chun-Hui Liu
- Department of Neurosurgery, Beijing Tiantan Hospital, Beijing, China
- Chun-Hui Liu,
| | - Xun Wang
- Department of Neurosurgery, Affiliated Dalian No. 3 People’s Hospital, Dalian Medical University, Dalian, China
- *Correspondence: Xun Wang,
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29
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Orozco CA, González-Giraldo Y, Bonilla DA, Forero DA. An in silico analysis of genome-wide expression profiles of the effects of exhaustive exercise identifies heat shock proteins as the key players. Meta Gene 2022. [DOI: 10.1016/j.mgene.2022.101012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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30
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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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31
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Houle S, Kokiko-Cochran ON. A Levee to the Flood: Pre-injury Neuroinflammation and Immune Stress Influence Traumatic Brain Injury Outcome. Front Aging Neurosci 2022; 13:788055. [PMID: 35095471 PMCID: PMC8790486 DOI: 10.3389/fnagi.2021.788055] [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: 10/01/2021] [Accepted: 12/14/2021] [Indexed: 11/13/2022] Open
Abstract
Increasing evidence demonstrates that aging influences the brain's response to traumatic brain injury (TBI), setting the stage for neurodegenerative pathology like Alzheimer's disease (AD). This topic is often dominated by discussions of post-injury aging and inflammation, which can diminish the consideration of those same factors before TBI. In fact, pre-TBI aging and inflammation may be just as critical in mediating outcomes. For example, elderly individuals suffer from the highest rates of TBI of all severities. Additionally, pre-injury immune challenges or stressors may alter pathology and outcome independent of age. The inflammatory response to TBI is malleable and influenced by previous, coincident, and subsequent immune insults. Therefore, pre-existing conditions that elicit or include an inflammatory response could substantially influence the brain's ability to respond to traumatic injury and ultimately affect chronic outcome. The purpose of this review is to detail how age-related cellular and molecular changes, as well as genetic risk variants for AD affect the neuroinflammatory response to TBI. First, we will review the sources and pathology of neuroinflammation following TBI. Then, we will highlight the significance of age-related, endogenous sources of inflammation, including changes in cytokine expression, reactive oxygen species processing, and mitochondrial function. Heightened focus is placed on the mitochondria as an integral link between inflammation and various genetic risk factors for AD. Together, this review will compile current clinical and experimental research to highlight how pre-existing inflammatory changes associated with infection and stress, aging, and genetic risk factors can alter response to TBI.
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Affiliation(s)
- Samuel Houle
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH, United States,Institute for Behavioral Medicine Research, Neurological Institute, The Ohio State University, Columbus, OH, United States
| | - Olga N. Kokiko-Cochran
- Department of Neuroscience, College of Medicine, The Ohio State University, Columbus, OH, United States,Institute for Behavioral Medicine Research, Neurological Institute, The Ohio State University, Columbus, OH, United States,*Correspondence: Olga N. Kokiko-Cochran
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32
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Sanjay, Kim JY. Anti-inflammatory effects of 9-cis-retinoic acid on β-amyloid treated human microglial cells. EUR J INFLAMM 2022. [DOI: 10.1177/1721727x221143651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Objective: Alzheimer’s disease (AD) is a neurodegenerative disease that abolishes cognitive and analytical abilities to perform basic day-to-day tasks. Microglia are involved in AD-associated neuroinflammation in response to amyloid β‐peptide (Aβ). This study focused on observing the immunomodulatory effects of 9-cis-retinoic acid (9-Cis-RA) the active metabolite of vitamin A, on Aβ-treated human microglial HMO6 cells. Methods: HMO6 cells were treated with Aβ42 in the absence or presence of 9-cis-RA, and the expression of M1-and M2-associated molecules, Toll like receptors (TLRs), and triggering receptor expressed on myeloid cells 2 (TREM2) were examined. Results: The levels of M1-markers [cluster of differentiation (CD86) and inducible nitric oxide synthase (iNOS)] and -cytokines [tumor necrosis factor (TNF-α), interleukin (IL)-6, and IL-1β], inflammatory receptors (TLR2 and TLR4), and reactive oxygen species increased significantly in Aβ-treated HMO6 cells. In contrast, the levels of M2-markers (CD206 and arginase-1) and -cytokines (IL-10, IL-4, and C-C motif chemokine ligand 17) the anti-inflammatory receptor TLR10 was significantly suppressed. However, 9-cis-RA treatment reversed the Aβ-induced upregulation of expression of M1-associated molecules and upregulated the expression of M2-associated molecules. Moreover, 9-cis-RA treatment augmented Aβ uptake by HMO6 cells, possibly by increasing the cell surface protein levels of TREM2, which is a receptor of Aβ that promotes Aβ phagocytosis by microglia. Conclusion: Our results suggest that 9-cis-RA is a potential therapeutic agent for AD.
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Affiliation(s)
- Sanjay
- Department of Life Science, Gachon University, Seongnam, Korea
| | - Jae Young Kim
- Department of Life Science, Gachon University, Seongnam, Korea
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33
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Magusali N, Graham AC, Piers TM, Panichnantakul P, Yaman U, Shoai M, Reynolds RH, Botia JA, Brookes KJ, Guetta-Baranes T, Bellou E, Bayram S, Sokolova D, Ryten M, Sala Frigerio C, Escott-Price V, Morgan K, Pocock JM, Hardy J, Salih DA. A genetic link between risk for Alzheimer's disease and severe COVID-19 outcomes via the OAS1 gene. Brain 2021; 144:3727-3741. [PMID: 34619763 PMCID: PMC8500089 DOI: 10.1093/brain/awab337] [Citation(s) in RCA: 60] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 07/19/2021] [Accepted: 08/02/2021] [Indexed: 01/12/2023] Open
Abstract
Recently, we reported oligoadenylate synthetase 1 (OAS1) contributed to the risk of Alzheimer's disease, by its enrichment in transcriptional networks expressed by microglia. However, the function of OAS1 within microglia was not known. Using genotyping from 1313 individuals with sporadic Alzheimer's disease and 1234 control individuals, we confirm the OAS1 variant, rs1131454, is associated with increased risk for Alzheimer's disease. The same OAS1 locus has been recently associated with severe coronavirus disease 2019 (COVID-19) outcomes, linking risk for both diseases. The single nucleotide polymorphisms rs1131454(A) and rs4766676(T) are associated with Alzheimer's disease, and rs10735079(A) and rs6489867(T) are associated with severe COVID-19, where the risk alleles are linked with decreased OAS1 expression. Analysing single-cell RNA-sequencing data of myeloid cells from Alzheimer's disease and COVID-19 patients, we identify co-expression networks containing interferon (IFN)-responsive genes, including OAS1, which are significantly upregulated with age and both diseases. In human induced pluripotent stem cell-derived microglia with lowered OAS1 expression, we show exaggerated production of TNF-α with IFN-γ stimulation, indicating OAS1 is required to limit the pro-inflammatory response of myeloid cells. Collectively, our data support a link between genetic risk for Alzheimer's disease and susceptibility to critical illness with COVID-19 centred on OAS1, a finding with potential implications for future treatments of Alzheimer's disease and COVID-19, and development of biomarkers to track disease progression.
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Affiliation(s)
- Naciye Magusali
- UK Dementia Research Institute at UCL, Gower Street, London WC1E 6BT, UK
| | - Andrew C Graham
- UK Dementia Research Institute at UCL, Gower Street, London WC1E 6BT, UK
| | - Thomas M Piers
- Department of Neuroinflammation, Queen Square Institute of Neurology, UCL, London WC1N 1PJ, UK
| | | | - Umran Yaman
- UK Dementia Research Institute at UCL, Gower Street, London WC1E 6BT, UK
| | - Maryam Shoai
- UK Dementia Research Institute at UCL, Gower Street, London WC1E 6BT, UK
- Department of Neurodegenerative Diseases, Queen Square Institute of Neurology, UCL, London WC1N 1PJ, UK
| | - Regina H Reynolds
- Department of Neurodegenerative Diseases, Queen Square Institute of Neurology, UCL, London WC1N 1PJ, UK
- NIHR Great Ormond Street Hospital Biomedical Research Centre, UCL, London WC1N 1EH, UK
- Great Ormond Street Institute of Child Health, Genetics and Genomic Medicine, UCL, London WC1N 1EH, UK
| | - Juan A Botia
- Department of Neurodegenerative Diseases, Queen Square Institute of Neurology, UCL, London WC1N 1PJ, UK
- Department of Information and Communications Engineering, Universidad de Murcia, 30100 Murcia, Spain
| | - Keeley J Brookes
- Biosciences, School of Science and Technology, Nottingham Trent University, Nottingham NG8 11NS, UK
| | - Tamar Guetta-Baranes
- Genetics, School of Life Sciences, Life Sciences Building, University Park, University of Nottingham, Nottingham NG7 2RD, UK
| | - Eftychia Bellou
- Dementia Research Institute, MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff University, Cardiff CF24 4HQ, UK
| | - Sevinc Bayram
- Hitachi Rail Europe Ltd, New Ludgate, London EC4M 7HX, UK
| | - Dimitra Sokolova
- UK Dementia Research Institute at UCL, Gower Street, London WC1E 6BT, UK
| | - Mina Ryten
- Department of Neurodegenerative Diseases, Queen Square Institute of Neurology, UCL, London WC1N 1PJ, UK
- NIHR Great Ormond Street Hospital Biomedical Research Centre, UCL, London WC1N 1EH, UK
- Great Ormond Street Institute of Child Health, Genetics and Genomic Medicine, UCL, London WC1N 1EH, UK
| | | | - Valentina Escott-Price
- Dementia Research Institute, MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff University, Cardiff CF24 4HQ, UK
| | - Kevin Morgan
- Genetics, School of Life Sciences, Life Sciences Building, University Park, University of Nottingham, Nottingham NG7 2RD, UK
| | - Jennifer M Pocock
- Department of Neuroinflammation, Queen Square Institute of Neurology, UCL, London WC1N 1PJ, UK
| | - John Hardy
- UK Dementia Research Institute at UCL, Gower Street, London WC1E 6BT, UK
- Department of Neurodegenerative Diseases, Queen Square Institute of Neurology, UCL, London WC1N 1PJ, UK
| | - Dervis A Salih
- UK Dementia Research Institute at UCL, Gower Street, London WC1E 6BT, UK
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Ruganzu JB, Peng X, He Y, Wu X, Zheng Q, Ding B, Lin C, Guo H, Yang Z, Zhang X, Yang W. Downregulation of TREM2 expression exacerbates neuroinflammatory responses through TLR4-mediated MAPK signaling pathway in a transgenic mouse model of Alzheimer's disease. Mol Immunol 2021; 142:22-36. [PMID: 34959070 DOI: 10.1016/j.molimm.2021.12.018] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 12/15/2021] [Accepted: 12/20/2021] [Indexed: 12/20/2022]
Abstract
Activation of glial cells and neuroinflammation play an important role in the onset and development of Alzheimer's disease (AD). Triggering receptor expressed on myeloid cells 2 (TREM2) is a microglia-specific receptor in the brain that is involved in regulating neuroinflammation. However, the precise effects of TREM2 on neuroinflammatory responses and its underlying molecular mechanisms in AD have not been studied in detail. Here, we employed a lentiviral-mediated strategy to downregulation of TREM2 expression on microglia in the brain of APPswe/PS1dE9 (APP/PS1) transgenic mice and BV2 cells. Our results showed that downregulation of TREM2 significantly aggravated AD-related neuropathology including Aβ accumulation, peri-plaque microgliosis and astrocytosis, as well as neuronal and synapse-associated proteins loss, which was accompanied by a decline in cognitive ability. The further mechanistic study revealed that downregulation of TREM2 expression initiated neuroinflammatory responses through toll-like receptor 4 (TLR4)-mediated mitogen-activated protein kinase (MAPK) signaling pathway and subsequent stimulating the production of pro-inflammatory cytokines in vivo and in vitro. Moreover, blockade of p38, JNK, and ERK1/2 inhibited the release of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6) induced by Aβ1-42 in TREM2-knocked down BV2 cells. Taken together, these findings indicated that TREM2 might be a potential therapeutic target for AD and other neuroinflammation-related diseases.
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Affiliation(s)
- John Bosco Ruganzu
- Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, 710061, Shaanxi, China
| | - Xiaoqian Peng
- Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, 710061, Shaanxi, China
| | - Yingying He
- Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, 710061, Shaanxi, China
| | - Xiangyuan Wu
- Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, 710061, Shaanxi, China
| | - Quzhao Zheng
- Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, 710061, Shaanxi, China
| | - Bo Ding
- Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, 710061, Shaanxi, China
| | - Chengheng Lin
- Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, 710061, Shaanxi, China
| | - Hongsong Guo
- Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, 710061, Shaanxi, China
| | - Zikang Yang
- Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, 710061, Shaanxi, China
| | - Xiao Zhang
- Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, 710061, Shaanxi, China
| | - Weina Yang
- Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, 710061, Shaanxi, China.
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35
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Zhao M, Jiang XF, Zhang HQ, Sun JH, Pei H, Ma LN, Cao Y, Li H. Interactions between glial cells and the blood-brain barrier and their role in Alzheimer's disease. Ageing Res Rev 2021; 72:101483. [PMID: 34610479 DOI: 10.1016/j.arr.2021.101483] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 09/14/2021] [Accepted: 09/30/2021] [Indexed: 12/11/2022]
Abstract
Alzheimer's disease (AD), which is an irreversible neurodegenerative disorder characterized by senile plaques and neurofibrillary tangles, is the most common form of dementia worldwide. However, currently, there are no satisfying curative therapies for AD. The blood-brain barrier (BBB) acts as a selective physical barrier and plays protective roles in maintaining brain homeostasis. BBB dysfunction as an upstream or downstream event promotes the onset and progression of AD. Moreover, the pathogenesis of AD caused by BBB injury hasn't been well elucidated. Glial cells, BBB compartments and neurons form a minimal functional unit called the neurovascular unit (NVU). Emerging evidence suggests that glial cells are regulators in maintaining the BBB integrity and neuronal function. Illustrating the regulatory mechanism of glial cells in the BBB assists us in drawing a glial-vascular coupling diagram of AD, which may offer new insight into the pathogenesis of AD and early intervention strategies for AD. This review aims to summarize our current knowledge of glial-BBB interactions and their pathological implications in AD and to provide new therapeutic potentials for future investigations.
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36
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Sek AC, Percopo CM, Boddapati AK, Ma M, Geslewitz WE, Krumholz JO, Lack JB, Rosenberg HF. Differential expression of Triggering Receptor Expressed on Myeloid cells 2 (Trem2) in tissue eosinophils. J Leukoc Biol 2021; 110:679-691. [PMID: 33404075 DOI: 10.1002/jlb.3a0920-620r] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Revised: 12/08/2020] [Accepted: 12/09/2020] [Indexed: 12/14/2022] Open
Abstract
No longer regarded simply as end-stage cytotoxic effectors, eosinophils are now recognized as complex cells with unique phenotypes that develop in response stimuli in the local microenvironment. In our previous study, we documented eosinophil infiltration in damaged muscle characteristic of dystrophin-deficient (mdx) mice that model Duchenne muscular dystrophy. Specifically, we found that eosinophils did not promote the generation of muscle lesions, as these persisted in eosinophil-deficient mdx.PHIL mice. To obtain additional insight into these findings, we performed RNA sequencing of eosinophils isolated from muscle tissue of mdx, IL5tg, and mdx.IL5tg mice. We observed profound up-regulation of classical effector proteins (major basic protein-1, eosinophil peroxidase, and eosinophil-associated ribonucleases) in eosinophils isolated from lesion-free muscle from IL5tg mice. By contrast, we observed significant up-regulation of tissue remodeling genes, including proteases, extracellular matrix components, collagen, and skeletal muscle precursors, as well as the immunomodulatory receptor, Trem2, in eosinophils isolated from skeletal muscle tissue from the dystrophin-deficient mdx mice. Although the anti-inflammatory properties of Trem2 have been described in the monocyte/macrophage lineage, no previous studies have documented its expression in eosinophils. We found that Trem2 was critical for full growth and differentiation of bone marrow-derived eosinophil cultures and full expression of TLR4. Immunoreactive Trem2 was also detected on human peripheral blood eosinophils at levels that correlated with donor body mass index and total leukocyte count. Taken together, our findings provide important insight into the immunomodulatory and remodeling capacity of mouse eosinophils and the flexibility of their gene expression profiles in vivo.
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Affiliation(s)
- Albert C Sek
- Inflammation Immunobiology Section, Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, 20892, USA
- Research Technologies Development Section, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, 20892, USA
- Merck Research Laboratories, South San Francisco, California, 94080, USA
| | - Caroline M Percopo
- Inflammation Immunobiology Section, Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, 20892, USA
- Research Technologies Development Section, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, 20892, USA
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, Twinbrook III, National Institutes of Health, Rockville, Maryland, 20851, USA
| | - Arun K Boddapati
- NIAID Collaborative Bioinformatics Resource, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, 20892, USA
- Advanced Biomedical Computational Science, Frederick National Laboratory for Cancer Research, Frederick, Maryland, 21701, USA
- Yerkes Genomics Core Laboratory, Yerkes National Primate Research Center, Emory University, Atlanta, GA, 30329, USA
| | - Michelle Ma
- Inflammation Immunobiology Section, Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, 20892, USA
- Research Technologies Development Section, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, 20892, USA
- Genetic Immunotherapy Section, Laboratory of Clinical Microbiology and Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, 20892, USA
| | - Wendy E Geslewitz
- Inflammation Immunobiology Section, Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, 20892, USA
- Research Technologies Development Section, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, 20892, USA
- Department of Microbiology and Immunology, Driskill Graduate Program in the Life Sciences, Northwestern University, Chicago, Illinois, 60611, USA
| | - Julia O Krumholz
- Inflammation Immunobiology Section, Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, 20892, USA
- Research Technologies Development Section, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, 20892, USA
- Boston University School of Medicine, Boston, Massachusetts, 02118, USA
| | - Justin B Lack
- NIAID Collaborative Bioinformatics Resource, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, 20892, USA
- Advanced Biomedical Computational Science, Frederick National Laboratory for Cancer Research, Frederick, Maryland, 21701, USA
| | - Helene F Rosenberg
- Inflammation Immunobiology Section, Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, 20892, USA
- Research Technologies Development Section, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, 20892, USA
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de Oliveira J, Kucharska E, Garcez ML, Rodrigues MS, Quevedo J, Moreno-Gonzalez I, Budni J. Inflammatory Cascade in Alzheimer's Disease Pathogenesis: A Review of Experimental Findings. Cells 2021; 10:cells10102581. [PMID: 34685563 PMCID: PMC8533897 DOI: 10.3390/cells10102581] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 09/13/2021] [Accepted: 09/16/2021] [Indexed: 12/14/2022] Open
Abstract
Alzheimer’s disease (AD) is the leading cause of dementia worldwide. Most AD patients develop the disease in late life, named late onset AD (LOAD). Currently, the most recognized explanation for AD pathology is the amyloid cascade hypothesis. It is assumed that amyloid beta (Aβ) aggregation and deposition are critical pathogenic processes in AD, leading to the formation of amyloid plaques, as well as neurofibrillary tangles, neuronal cell death, synaptic degeneration, and dementia. In LOAD, the causes of Aβ accumulation and neuronal loss are not completely clear. Importantly, the blood–brain barrier (BBB) disruption seems to present an essential role in the induction of neuroinflammation and consequent AD development. In addition, we propose that the systemic inflammation triggered by conditions like metabolic diseases or infections are causative factors of BBB disruption, coexistent inflammatory cascade and, ultimately, the neurodegeneration observed in AD. In this regard, the use of anti-inflammatory molecules could be an interesting strategy to treat, delay or even halt AD onset and progression. Herein, we review the inflammatory cascade and underlying mechanisms involved in AD pathogenesis and revise the anti-inflammatory effects of compounds as emerging therapeutic drugs against AD.
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Affiliation(s)
- Jade de Oliveira
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre 90050-000, Brazil; (J.d.O.); (M.S.R.)
| | - Ewa Kucharska
- Faculty of Education, Institute of Educational Sciences, Jesuit University Ignatianum in Krakow, 31-501 Krakow, Poland;
| | - Michelle Lima Garcez
- Department of Biochemistry, Federal University of Santa Catarina, Florianópolis 88040-900, Santa Catarina, Brazil;
| | - Matheus Scarpatto Rodrigues
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre 90050-000, Brazil; (J.d.O.); (M.S.R.)
| | - João Quevedo
- Translational Psychiatry Program, Faillace Department of Psychiatry and Behavioral Sciences, McGovern Medical School, The University of Texas Health Science Center at Houston (UTHealth), Houston, TX 77030, USA;
- Center of Excellence on Mood Disorders, Faillace Department of Psychiatry and Behavioral Sciences, McGovern Medical School, The University of Texas Health Science Center at Houston (UTHealth), Houston, TX 77030, USA
- Neuroscience Graduate Program, Graduate School of Biomedical Sciences, MD Anderson Cancer Center, UTHealth, The University of Texas Houston, Houston, TX 77030, USA
- Graduate Program in Health Sciences, Translational Psychiatry Laboratory, University of Southern Santa Catarina (UNESC), Criciuma 88806-000, Brazil
| | - Ines Moreno-Gonzalez
- Department of Cell Biology, Faculty of Sciences, University of Malaga, IBIMA, 29010 Malaga, Spain;
- Networking Research Center on Neurodegenerative Diseases (CIBERNED), 29010 Malaga, Spain
- Department of Neurology, McGovern Medical School, The University of Texas Health Science Center at Houston (UTHealth), Houston, TX 77030, USA
| | - Josiane Budni
- Programa de Pós-Graduação em Ciências da Saúde, Laboratório de Neurologia Experimental, Universidade do Extremo Sul Catarinense, Criciuma 88806-000, Brazil
- Correspondence: ; Tel.: +55-48431-2539
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38
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Xu X, Du L, Jiang J, Yang M, Wang Z, Wang Y, Tang T, Fu X, Hao J. Microglial TREM2 Mitigates Inflammatory Responses and Neuronal Apoptosis in Angiotensin II-Induced Hypertension in Middle-Aged Mice. Front Aging Neurosci 2021; 13:716917. [PMID: 34489683 PMCID: PMC8417947 DOI: 10.3389/fnagi.2021.716917] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Accepted: 07/16/2021] [Indexed: 11/15/2022] Open
Abstract
Growing evidence suggests that hypertension and aging are prominent risk factors for the development of late-onset Alzheimer's disease (LOAD) by inducement of neuroinflammation. Recent study showed that neuroinflammation via activated microglia induces reactive astrocytes, termed A1 astrocytes, that highly upregulate numerous classical complement cascade genes that are destructive to neurons in neurodegeneration diseases. Moreover, triggering receptor expressed on myeloid cells 2 (TREM2) is considered as one of the strongest single-allele genetic risk factors and plays important roles in neuroinflammation for LOAD. However, the mechanisms of microglia in the regulation of A1 astrocytic activation are still not clear. We introduced angiotensin II-induced hypertension in middle-aged mice and found that hypertension-upregulated TREM2 expression and A1 astrocytic activation were involved in neuroinflammation in the animal models used in this study. The in vitro results revealed that overexpression of microglial TREM2 not only mitigated microglial inflammatory response but also had salutary effects on reverse A1 astrocytic activation and neuronal toxicity.
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Affiliation(s)
- Xiaotian Xu
- Department of Neurology, The Affiliated Hospital, Yangzhou University, Yangzhou, China
- Department of Pharmacological & Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, TX, United States
| | - Lin Du
- Department of Cardiology, The Affiliated Hospital, Yangzhou University, Yangzhou, China
| | - Jianxiong Jiang
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN, United States
| | - Ming Yang
- Department of Neurology, The Affiliated Hospital, Yangzhou University, Yangzhou, China
| | - Zhaoxia Wang
- Department of Neurology, The Affiliated Hospital, Yangzhou University, Yangzhou, China
| | - Yingge Wang
- Department of Neurology, The Affiliated Hospital, Yangzhou University, Yangzhou, China
| | - Tieyu Tang
- Department of Neurology, The Affiliated Hospital, Yangzhou University, Yangzhou, China
| | - Xuetao Fu
- Department of Neurology, The Affiliated Hospital, Yangzhou University, Yangzhou, China
| | - Jiukuan Hao
- Department of Pharmacological & Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, TX, United States
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Role of TREM2 in Alzheimer's Disease: A Long Road Ahead. Mol Neurobiol 2021; 58:5239-5252. [PMID: 34275100 DOI: 10.1007/s12035-021-02477-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Accepted: 06/28/2021] [Indexed: 10/20/2022]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disease characterized by an increasing deterioration of memory, which is concomitant with additional cognitive deficits. Neurofibrillary tangles and senile plaques are two pivotal proteins inside the brain that are considered essential to obstruct the normal cognitive function of the brain. Genetic variations in TREM2 gene disturb the neuroinflammatory action of microglia in reducing the progression of the disease.TREM2 is a transmembrane receptor present on the microglia, which has an important function in neuroinflammation. Genome-wide association studies identified variants of TREM2 gene and linked it with the risk of developing AD, by 2-4 folds. Numerous studies on mice models have revealed the relationship between mutations of TREM2 gene and its effect on amyloid burden and tau pathology in the brain that gets affected by AD. This review summarizes the role of TREM2 and its variants in the progression of AD and tries to delve deep into the role of soluble TREM2 as an effective biomarker and impending neuroprotection in AD. It also focuses on the strategies to develop therapeutic agents against TREM2 by employing its expression, function, and signalling pathways. The current challenges posed against prospective therapy for AD are also discussed.
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40
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Wang SY, Gong PY, E Y, Zhang YD, Jiang T. The Role of TREML2 in Alzheimer's Disease. J Alzheimers Dis 2021; 76:799-806. [PMID: 32568208 DOI: 10.3233/jad-200406] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Late-onset Alzheimer's disease (AD) accounts for most of all AD casesand is currently considered a complex disorder caused by a combination of environmental and genetic factors. As an important family member of triggering receptor expressed on myeloid cells (TREM), TREM-like transcript 2 gene (TREML2) locates on human chromosome 6p21.1, a newly-identified hot zone for AD susceptibility, and encodes atransmembrane immune receptor. Emerging evidence implied a potential role of TREML2 in the susceptibility and pathogenesis of AD. Here, we review the recent literature about the association of TREML2 variants with AD risk and disease endophenotypes. Moreover, we summarize the latest findings regarding cellular localization and biological functions of TREML2 and speculate its possible role in AD pathogenesis. In addition, we discuss future research directions of TREML2 and AD.
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Affiliation(s)
- Si-Yu Wang
- Department of Neurology, Nanjing First Hospital, Nanjing Medical University, Nanjing, China.,Department of Neurology, Nanjing Yuhua Hospital, Nanjing, China
| | - Peng-Yu Gong
- Department of Neurology, Nanjing First Hospital, Nanjing Medical University, Nanjing, China.,Department of Neurology, Nanjing Yuhua Hospital, Nanjing, China
| | - Yan E
- Department of Neurology, Nanjing First Hospital, Nanjing Medical University, Nanjing, China.,Department of Neurology, Nanjing Yuhua Hospital, Nanjing, China
| | - Ying-Dong Zhang
- Department of Neurology, Nanjing First Hospital, Nanjing Medical University, Nanjing, China.,Department of Neurology, Nanjing Yuhua Hospital, Nanjing, China.,School of Basic Medicine & Clinical Pharmacy, China Pharmaceutical University, Nanjing, China
| | - Teng Jiang
- Department of Neurology, Nanjing First Hospital, Nanjing Medical University, Nanjing, China.,Department of Neurology, Nanjing Yuhua Hospital, Nanjing, China
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41
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Seto M, Weiner RL, Dumitrescu L, Hohman TJ. Protective genes and pathways in Alzheimer's disease: moving towards precision interventions. Mol Neurodegener 2021; 16:29. [PMID: 33926499 PMCID: PMC8086309 DOI: 10.1186/s13024-021-00452-5] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 04/20/2021] [Indexed: 12/29/2022] Open
Abstract
Alzheimer's disease (AD) is a progressive, neurodegenerative disorder that is characterized by neurodegeneration, cognitive impairment, and an eventual inability to perform daily tasks. The etiology of Alzheimer's is complex, with numerous environmental and genetic factors contributing to the disease. Late-onset AD is highly heritable (60 to 80%), and over 40 risk loci for AD have been identified via large genome-wide association studies, most of which are common variants with small effect sizes. Although these discoveries have provided novel insight on biological contributors to AD, disease-modifying treatments remain elusive. Recently, the concepts of resistance to pathology and resilience against the downstream consequences of pathology have been of particular interest in the Alzheimer's field as studies continue to identify individuals who evade the pathology of the disease even into late life and individuals who have all of the neuropathological features of AD but evade downstream neurodegeneration and cognitive impairment. It has been hypothesized that a shift in focus from Alzheimer's risk to resilience presents an opportunity to uncover novel biological mechanisms of AD and to identify promising therapeutic targets for the disease. This review will highlight a selection of genes and variants that have been reported to confer protection from AD within the literature and will also discuss evidence for the biological underpinnings behind their protective effect with a focus on genes involved in lipid metabolism, cellular trafficking, endosomal and lysosomal function, synaptic function, and inflammation. Finally, we offer some recommendations in areas where the field can rapidly advance towards precision interventions that leverage the ideas of protection and resilience for the development of novel therapeutic strategies.
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Affiliation(s)
- Mabel Seto
- Vanderbilt Memory and Alzheimer’s Center, Vanderbilt University Medical Center, 1207 17th Ave S, Nashville, TN 37212 USA
- Vanderbilt Genetics Institute, Vanderbilt University Medical Center, Nashville, TN USA
- Department of Pharmacology, Vanderbilt University, Nashville, TN USA
| | - Rebecca L. Weiner
- Vanderbilt Memory and Alzheimer’s Center, Vanderbilt University Medical Center, 1207 17th Ave S, Nashville, TN 37212 USA
- Vanderbilt Genetics Institute, Vanderbilt University Medical Center, Nashville, TN USA
- Department of Pharmacology, Vanderbilt University, Nashville, TN USA
| | - Logan Dumitrescu
- Vanderbilt Memory and Alzheimer’s Center, Vanderbilt University Medical Center, 1207 17th Ave S, Nashville, TN 37212 USA
- Vanderbilt Genetics Institute, Vanderbilt University Medical Center, Nashville, TN USA
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN USA
| | - Timothy J. Hohman
- Vanderbilt Memory and Alzheimer’s Center, Vanderbilt University Medical Center, 1207 17th Ave S, Nashville, TN 37212 USA
- Vanderbilt Genetics Institute, Vanderbilt University Medical Center, Nashville, TN USA
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN USA
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42
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Cheon SY, Koo BN, Kim SY, Kam EH, Nam J, Kim EJ. Scopolamine promotes neuroinflammation and delirium-like neuropsychiatric disorder in mice. Sci Rep 2021; 11:8376. [PMID: 33863952 PMCID: PMC8052461 DOI: 10.1038/s41598-021-87790-y] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Accepted: 04/05/2021] [Indexed: 01/13/2023] Open
Abstract
Postoperative delirium is a common neuropsychiatric syndrome resulting a high postsurgical mortality rate and decline in postdischarge function. Extensive research has been performed on both human and animal delirium-like models due to their clinical significance, focusing on systematic inflammation and consequent neuroinflammation playing a key role in the pathogenesis of postoperative cognitive dysfunctions. Since animal models are widely utilized for pathophysiological study of neuropsychiatric disorders, this study aimed at examining the validity of the scopolamine-induced delirium-like mice model with respect to the neuroinflammatory hypothesis of delirium. Male C57BL/6 mice were treated with intraperitoneal scopolamine (2 mg/kg). Neurobehavioral tests were performed to evaluate the changes in cognitive functions, including learning and memory, and the level of anxiety after surgery or scopolamine treatment. The levels of pro-inflammatory cytokines (IL-1β, IL-18, and TNF-α) and inflammasome components (NLRP3, ASC, and caspase-1) in different brain regions were measured. Gene expression profiles were also examined using whole-genome RNA sequencing analyses to compare gene expression patterns of different mice models. Scopolamine treatment showed significant increase in the level of anxiety and impairments in memory and cognitive function associated with increased level of pro-inflammatory cytokines and NLRP3 inflammasome components. Genetic analysis confirmed the different expression patterns of genes involved in immune response and inflammation and those related with the development of the nervous system in both surgery and scopolamine-induced mice models. The scopolamine-induced delirium-like mice model successfully showed that analogous neuropsychiatric changes coincides with the neuroinflammatory hypothesis for pathogenesis of delirium.
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Affiliation(s)
- So Yeong Cheon
- Department of Biotechnology, College of Biomedical and Health Science, Konkuk University, Chungju, Republic of Korea
| | - Bon-Nyeo Koo
- Department of Anesthesiology and Pain Medicine, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea.,Anesthesia and Pain Research Institute, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - So Yeon Kim
- Department of Anesthesiology and Pain Medicine, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea.,Anesthesia and Pain Research Institute, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Eun Hee Kam
- Department of Anesthesiology and Pain Medicine, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea.,Anesthesia and Pain Research Institute, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Junhyun Nam
- Department of Anesthesiology and Pain Medicine, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea
| | - Eun Jung Kim
- Department of Anesthesiology and Pain Medicine, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea. .,Anesthesia and Pain Research Institute, Yonsei University College of Medicine, Seoul, Republic of Korea.
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Imaging Biomarkers for Monitoring the Inflammatory Redox Landscape in the Brain. Antioxidants (Basel) 2021; 10:antiox10040528. [PMID: 33800685 PMCID: PMC8065574 DOI: 10.3390/antiox10040528] [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: 02/18/2021] [Revised: 03/21/2021] [Accepted: 03/25/2021] [Indexed: 12/27/2022] Open
Abstract
Inflammation is one key process in driving cellular redox homeostasis toward oxidative stress, which perpetuates inflammation. In the brain, this interplay results in a vicious cycle of cell death, the loss of neurons, and leakage of the blood–brain barrier. Hence, the neuroinflammatory response fuels the development of acute and chronic inflammatory diseases. Interrogation of the interplay between inflammation, oxidative stress, and cell death in neurological tissue in vivo is very challenging. The complexity of the underlying biological process and the fragility of the brain limit our understanding of the cause and the adequate diagnostics of neuroinflammatory diseases. In recent years, advancements in the development of molecular imaging agents addressed this limitation and enabled imaging of biomarkers of neuroinflammation in the brain. Notable redox biomarkers for imaging with positron emission tomography (PET) tracers are the 18 kDa translocator protein (TSPO) and monoamine oxygenase B (MAO–B). These findings and achievements offer the opportunity for novel diagnostic applications and therapeutic strategies. This review summarizes experimental as well as established pharmaceutical and biotechnological tools for imaging the inflammatory redox landscape in the brain, and provides a glimpse into future applications.
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Vogrinc D, Goričar K, Dolžan V. Genetic Variability in Molecular Pathways Implicated in Alzheimer's Disease: A Comprehensive Review. Front Aging Neurosci 2021; 13:646901. [PMID: 33815092 PMCID: PMC8012500 DOI: 10.3389/fnagi.2021.646901] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Accepted: 02/16/2021] [Indexed: 12/14/2022] Open
Abstract
Alzheimer's disease (AD) is a complex neurodegenerative disease, affecting a significant part of the population. The majority of AD cases occur in the elderly with a typical age of onset of the disease above 65 years. AD presents a major burden for the healthcare system and since population is rapidly aging, the burden of the disease will increase in the future. However, no effective drug treatment for a full-blown disease has been developed to date. The genetic background of AD is extensively studied; numerous genome-wide association studies (GWAS) identified significant genes associated with increased risk of AD development. This review summarizes more than 100 risk loci. Many of them may serve as biomarkers of AD progression, even in the preclinical stage of the disease. Furthermore, we used GWAS data to identify key pathways of AD pathogenesis: cellular processes, metabolic processes, biological regulation, localization, transport, regulation of cellular processes, and neurological system processes. Gene clustering into molecular pathways can provide background for identification of novel molecular targets and may support the development of tailored and personalized treatment of AD.
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Affiliation(s)
| | | | - Vita Dolžan
- Pharmacogenetics Laboratory, Institute of Biochemistry and Molecular Genetics, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
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45
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TREM2, microglia, and Alzheimer's disease. Mech Ageing Dev 2021; 195:111438. [PMID: 33516818 DOI: 10.1016/j.mad.2021.111438] [Citation(s) in RCA: 72] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 01/02/2021] [Accepted: 01/17/2021] [Indexed: 12/19/2022]
Abstract
Triggering receptor expressed on myeloid cells 2 (TREM2) has been suggested to play a crucial role in Alzheimer's disease (AD) pathogenesis, as revealed by genome-wide association studies (GWAS). Since then, rapidly increasing literature related to TREM2 has focused on elucidating its role in AD pathology. In this review, we summarize our understanding of TREM2 biology, explore TREM2 functions in microglia, address the multiple mechanisms of TREM2 in AD, and raise key questions for further investigations to elucidate the detailed roles and molecular mechanisms of TREM2 in microglial responses. A major breakthrough in our understanding of TREM2 is based on our hypothesis suggesting that TREM2 may act as a multifaceted player in microglial functions in AD brain homeostasis. We conclude that TREM2 can not only influence microglial functions in amyloid and tau pathologies but also participate in inflammatory responses and metabolism, acting alone or with other molecules, such as apolipoprotein E (APOE). This review provides novel insight into the broad role of TREM2 in microglial function in AD and enables us to develop new strategies aimed at the immune system to treat AD pathogenesis.
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46
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Liu W, Taso O, Wang R, Bayram S, Graham AC, Garcia-Reitboeck P, Mallach A, Andrews WD, Piers TM, Botia JA, Pocock JM, Cummings DM, Hardy J, Edwards FA, Salih DA. Trem2 promotes anti-inflammatory responses in microglia and is suppressed under pro-inflammatory conditions. Hum Mol Genet 2020; 29:3224-3248. [PMID: 32959884 PMCID: PMC7689298 DOI: 10.1093/hmg/ddaa209] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 09/07/2020] [Accepted: 09/09/2020] [Indexed: 12/22/2022] Open
Abstract
Genome-wide association studies have reported that, amongst other microglial genes, variants in TREM2 can profoundly increase the incidence of developing Alzheimer's disease (AD). We have investigated the role of TREM2 in primary microglial cultures from wild type mice by using siRNA to decrease Trem2 expression, and in parallel from knock-in mice heterozygous or homozygous for the Trem2 R47H AD risk variant. The prevailing phenotype of Trem2 R47H knock-in mice was decreased expression levels of Trem2 in microglia, which resulted in decreased density of microglia in the hippocampus. Overall, primary microglia with reduced Trem2 expression, either by siRNA or from the R47H knock-in mice, displayed a similar phenotype. Comparison of the effects of decreased Trem2 expression under conditions of lipopolysaccharide (LPS) pro-inflammatory or IL-4 anti-inflammatory stimulation revealed the importance of Trem2 in driving a number of the genes up-regulated in the anti-inflammatory phenotype. RNA-seq analysis showed that IL-4 induced the expression of a program of genes including Arg1 and Ap1b1 in microglia, which showed an attenuated response to IL-4 when Trem2 expression was decreased. Genes showing a similar expression profile to Arg1 were enriched for STAT6 transcription factor recognition elements in their promoter, and Trem2 knockdown decreased levels of STAT6. LPS-induced pro-inflammatory stimulation suppressed Trem2 expression, thus preventing TREM2's anti-inflammatory drive. Given that anti-inflammatory signaling is associated with tissue repair, understanding the signaling mechanisms downstream of Trem2 in coordinating the pro- and anti-inflammatory balance of microglia, particularly mediating effects of the IL-4-regulated anti-inflammatory pathway, has important implications for fighting neurodegenerative disease.
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Affiliation(s)
- Wenfei Liu
- Department of Neuroscience, Physiology and Pharmacology, UCL, London WC1E 6BT, UK
| | - Orjona Taso
- UK Dementia Research Institute at UCL, London WC1E 6BT, UK
| | - Rui Wang
- Department of Neuroscience, Physiology and Pharmacology, UCL, London WC1E 6BT, UK
| | | | | | | | - Anna Mallach
- Department of Neuroinflammation, Institute of Neurology, UCL, London WC1N 1PJ, UK
| | - William D Andrews
- Department of Cell and Developmental Biology, UCL, London WC1E 6BT, UK
| | - Thomas M Piers
- Department of Neuroinflammation, Institute of Neurology, UCL, London WC1N 1PJ, UK
| | - Juan A Botia
- Department of Information and Communications Engineering, Universidad de Murcia, Murcia E-30100, Spain
- Department of Neurodegenerative Diseases, Institute of Neurology, UCL, London WC1N 1PJ, UK
| | - Jennifer M Pocock
- Department of Neuroinflammation, Institute of Neurology, UCL, London WC1N 1PJ, UK
| | - Damian M Cummings
- Department of Neuroscience, Physiology and Pharmacology, UCL, London WC1E 6BT, UK
| | - John Hardy
- UK Dementia Research Institute at UCL, London WC1E 6BT, UK
- Department of Neurodegenerative Diseases, Institute of Neurology, UCL, London WC1N 1PJ, UK
| | - Frances A Edwards
- Department of Neuroscience, Physiology and Pharmacology, UCL, London WC1E 6BT, UK
| | - Dervis A Salih
- Department of Neuroscience, Physiology and Pharmacology, UCL, London WC1E 6BT, UK
- UK Dementia Research Institute at UCL, London WC1E 6BT, UK
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McQuade A, Kang YJ, Hasselmann J, Jairaman A, Sotelo A, Coburn M, Shabestari SK, Chadarevian JP, Fote G, Tu CH, Danhash E, Silva J, Martinez E, Cotman C, Prieto GA, Thompson LM, Steffan JS, Smith I, Davtyan H, Cahalan M, Cho H, Blurton-Jones M. Gene expression and functional deficits underlie TREM2-knockout microglia responses in human models of Alzheimer's disease. Nat Commun 2020; 11:5370. [PMID: 33097708 PMCID: PMC7584603 DOI: 10.1038/s41467-020-19227-5] [Citation(s) in RCA: 131] [Impact Index Per Article: 32.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 09/30/2020] [Indexed: 12/11/2022] Open
Abstract
The discovery of TREM2 as a myeloid-specific Alzheimer's disease (AD) risk gene has accelerated research into the role of microglia in AD. While TREM2 mouse models have provided critical insight, the normal and disease-associated functions of TREM2 in human microglia remain unclear. To examine this question, we profile microglia differentiated from isogenic, CRISPR-modified TREM2-knockout induced pluripotent stem cell (iPSC) lines. By combining transcriptomic and functional analyses with a chimeric AD mouse model, we find that TREM2 deletion reduces microglial survival, impairs phagocytosis of key substrates including APOE, and inhibits SDF-1α/CXCR4-mediated chemotaxis, culminating in an impaired response to beta-amyloid plaques in vivo. Single-cell sequencing of xenotransplanted human microglia further highlights a loss of disease-associated microglial (DAM) responses in human TREM2 knockout microglia that we validate by flow cytometry and immunohistochemistry. Taken together, these studies reveal both conserved and novel aspects of human TREM2 biology that likely play critical roles in the development and progression of AD.
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Affiliation(s)
- Amanda McQuade
- grid.266093.80000 0001 0668 7243Department of Neurobiology & Behavior, University of California Irvine, Irvine, CA 92697 USA ,grid.266093.80000 0001 0668 7243Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697 USA ,grid.266093.80000 0001 0668 7243Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, CA 92697 USA
| | - You Jung Kang
- grid.266859.60000 0000 8598 2218Department of Mechanical Engineering and Engineering Science, University of North Carolina Charlotte, Charlotte, NC 28223 USA ,grid.266859.60000 0000 8598 2218Department of Biological Sciences, University of North Carolina Charlotte, Charlotte, NC 28223 USA ,grid.266859.60000 0000 8598 2218Nanoscale Science Program, University of North Carolina Charlotte, Charlotte, NC 28223 USA ,grid.266859.60000 0000 8598 2218Center for Biomedical Engineering and Science, University of North Carolina Charlotte, Charlotte, NC 28223 USA
| | - Jonathan Hasselmann
- grid.266093.80000 0001 0668 7243Department of Neurobiology & Behavior, University of California Irvine, Irvine, CA 92697 USA ,grid.266093.80000 0001 0668 7243Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697 USA ,grid.266093.80000 0001 0668 7243Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, CA 92697 USA
| | - Amit Jairaman
- grid.266093.80000 0001 0668 7243Department of Physiology and Biophysics, University of California Irvine, Irvine, CA 92697 USA
| | - Alexandra Sotelo
- grid.266093.80000 0001 0668 7243Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697 USA
| | - Morgan Coburn
- grid.266093.80000 0001 0668 7243Department of Neurobiology & Behavior, University of California Irvine, Irvine, CA 92697 USA ,grid.266093.80000 0001 0668 7243Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697 USA ,grid.266093.80000 0001 0668 7243Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, CA 92697 USA
| | - Sepideh Kiani Shabestari
- grid.266093.80000 0001 0668 7243Department of Neurobiology & Behavior, University of California Irvine, Irvine, CA 92697 USA ,grid.266093.80000 0001 0668 7243Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697 USA
| | - Jean Paul Chadarevian
- grid.266093.80000 0001 0668 7243Department of Neurobiology & Behavior, University of California Irvine, Irvine, CA 92697 USA ,grid.266093.80000 0001 0668 7243Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697 USA ,grid.266093.80000 0001 0668 7243Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, CA 92697 USA
| | - Gianna Fote
- grid.266093.80000 0001 0668 7243Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697 USA ,grid.266093.80000 0001 0668 7243Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, CA 92697 USA
| | - Christina H. Tu
- grid.266093.80000 0001 0668 7243Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697 USA ,grid.266093.80000 0001 0668 7243Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, CA 92697 USA
| | - Emma Danhash
- grid.266093.80000 0001 0668 7243Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697 USA ,grid.266093.80000 0001 0668 7243Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, CA 92697 USA
| | - Jorge Silva
- grid.266093.80000 0001 0668 7243Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697 USA
| | - Eric Martinez
- grid.266093.80000 0001 0668 7243Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697 USA
| | - Carl Cotman
- grid.266093.80000 0001 0668 7243Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, CA 92697 USA
| | - G. Aleph Prieto
- grid.266093.80000 0001 0668 7243Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, CA 92697 USA ,grid.9486.30000 0001 2159 0001Institute of Neurobiology, National Autonomous University of Mexico, Queretaro, Mexico
| | - Leslie M. Thompson
- grid.266093.80000 0001 0668 7243Department of Neurobiology & Behavior, University of California Irvine, Irvine, CA 92697 USA ,grid.266093.80000 0001 0668 7243Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697 USA ,grid.266093.80000 0001 0668 7243Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, CA 92697 USA ,grid.266859.60000 0000 8598 2218Department of Biological Sciences, University of North Carolina Charlotte, Charlotte, NC 28223 USA
| | - Joan S. Steffan
- grid.266093.80000 0001 0668 7243Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697 USA ,grid.266093.80000 0001 0668 7243Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, CA 92697 USA ,grid.266093.80000 0001 0668 7243Department of Psychology and Human Behavior, University of California Irvine, Irvine, CA 92697 USA
| | - Ian Smith
- grid.266093.80000 0001 0668 7243Department of Neurobiology & Behavior, University of California Irvine, Irvine, CA 92697 USA
| | - Hayk Davtyan
- grid.266093.80000 0001 0668 7243Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA 92697 USA ,grid.266093.80000 0001 0668 7243Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, CA 92697 USA
| | - Michael Cahalan
- grid.266093.80000 0001 0668 7243Department of Physiology and Biophysics, University of California Irvine, Irvine, CA 92697 USA
| | - Hansang Cho
- grid.266859.60000 0000 8598 2218Department of Mechanical Engineering and Engineering Science, University of North Carolina Charlotte, Charlotte, NC 28223 USA ,grid.266859.60000 0000 8598 2218Department of Biological Sciences, University of North Carolina Charlotte, Charlotte, NC 28223 USA ,grid.266859.60000 0000 8598 2218Nanoscale Science Program, University of North Carolina Charlotte, Charlotte, NC 28223 USA ,grid.266859.60000 0000 8598 2218Center for Biomedical Engineering and Science, University of North Carolina Charlotte, Charlotte, NC 28223 USA ,grid.264381.a0000 0001 2181 989XDepartment of Biophysics, Sungkyunkwan University, Suwon, 16419 Korea
| | - Mathew Blurton-Jones
- Department of Neurobiology & Behavior, University of California Irvine, Irvine, CA, 92697, USA. .,Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, CA, 92697, USA. .,Institute for Memory Impairments and Neurological Disorders, University of California Irvine, Irvine, CA, 92697, USA.
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Kober DL, Stuchell-Brereton MD, Kluender CE, Dean HB, Strickland MR, Steinberg DF, Nelson SS, Baban B, Holtzman DM, Frieden C, Alexander-Brett J, Roberson ED, Song Y, Brett TJ. Functional insights from biophysical study of TREM2 interactions with apoE and Aβ 1-42. Alzheimers Dement 2020; 17:10.1002/alz.12194. [PMID: 33090700 PMCID: PMC8026773 DOI: 10.1002/alz.12194] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 08/12/2020] [Accepted: 08/20/2020] [Indexed: 12/20/2022]
Abstract
INTRODUCTION Triggering receptor expressed on myeloid cells-2 (TREM2) is an immune receptor expressed on microglia that also can become soluble (sTREM2). How TREM2 engages different ligands remains poorly understood. METHODS We used comprehensive biolayer interferometry (BLI) analysis to investigate TREM2 and sTREM2 interactions with apolipoprotein E (apoE) and monomeric amyloid beta (Aβ) (mAβ42). RESULTS TREM2 engagement of apoE was protein mediated with little effect of lipidation, showing slight affinity differences between isoforms (E4 > E3 > E2). Another family member, TREML2, did not bind apoE. Disease-linked TREM2 variants within a "basic patch" minimally impact apoE binding. Instead, TREM2 uses a unique hydrophobic surface to bind apoE, which requires the apoE hinge region. TREM2 and sTREM2 directly bind mAβ42 and potently inhibit Aβ42 polymerization, suggesting a potential role for soluble sTREM2 in preventing AD pathogenesis. DISCUSSION These findings demonstrate that TREM2 has at least two ligand-binding surfaces that might be therapeutic targets and uncovers a potential function for sTREM2 in directly inhibiting Aβ polymerization.
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Affiliation(s)
- Daniel L. Kober
- Molecular Microbiology and Microbial Pathogenesis Program, Washington University School of Medicine, St. Louis, Missouri 63110
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Melissa D. Stuchell-Brereton
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Colin E. Kluender
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110
- Biochemistry, Biophysics, and Structural Biology Program, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Hunter B. Dean
- Center for Neurodegeneration and Experimental Therapeutics, Alzheimer’s Disease Center, Departments of Neurology and Neurobiology, University of Alabama at Birmingham, AL 35294
- Department of Biomedical Engineering, University of Alabama at Birmingham, AL 35294
| | - Michael R. Strickland
- Department of Neurology, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Deborah F. Steinberg
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Samantha S. Nelson
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Berevan Baban
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110
| | - David M. Holtzman
- Department of Neurology, Washington University School of Medicine, St. Louis, Missouri 63110
- Charles F. and Joanne Knight Alzheimer’s Disease Research Center, Washington University School of Medicine, St. Louis, Missouri 63110
- Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Carl Frieden
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110
- Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Jennifer Alexander-Brett
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Erik D. Roberson
- Center for Neurodegeneration and Experimental Therapeutics, Alzheimer’s Disease Center, Departments of Neurology and Neurobiology, University of Alabama at Birmingham, AL 35294
| | - Yuhua Song
- Department of Biomedical Engineering, University of Alabama at Birmingham, AL 35294
| | - Tom J. Brett
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110
- Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, Missouri 63110
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri 63110
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49
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Li J, Cao C, Xiang Y, Hong Z, He D, Zhong H, Liu Y, Wu Y, Zheng X, Yin H, Zhou J, Xie H, Huang X. TLT2 Suppresses Th1 Response by Promoting IL-6 Production in Monocyte Through JAK/STAT3 Signal Pathway in Tuberculosis. Front Immunol 2020; 11:2031. [PMID: 33042115 PMCID: PMC7516513 DOI: 10.3389/fimmu.2020.02031] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Accepted: 07/27/2020] [Indexed: 01/19/2023] Open
Abstract
The function of triggering receptor expressed on myeloid cell-like transcript 2 (TLT2) has not been characterized and their role in pulmonary tuberculosis (TB) remains unclear. In this study, we found that surface TLT2 was up-regulated in human monocytes of patients with active TB compared to healthy subjects. In vitro, TLT2 expression was induced in human monocyte cell line THP-1 cells after bacillus Calmette-Guérin (BCG) or Mycobacterium tuberculosis (Mtb) H37Rv infection. Knockdown of TLT2 by siRNA transfection suppressed IL-6 expression, whereas over-expression of TLT2 increased IL-6 production in THP-1 cells infected by H37Rv. TLT2+CD14+ monocytes produced higher level of IL-6 compared to TLT2– subset in active TB patients. Western blot and immunocoprecipitation revealed that TLT2 interacted with kinase JAK1/JAK2/Tyk2 to enhance STAT3 phosphorylation. Moreover, we showed that tyrosine residues 297 and 315 of TLT2 cytoplasmic domain were involved in STAT3 activation. In monocyte/CD4+ T cell co-culture assay, blockage of TLT2 fusion protein facilitated IFN-γ production by CD4+ T cells. Plate count assay showed that monocyte-mediated bacterial killing was promoted by TLT2 fusion protein. In vivo treatment with TLT-2 fusion protein reduced IL-6 production by macrophage but increased IFN-γ production by CD4+ T cell in H37Rv and BCG infected mice. Furthermore, TLT2 fusion protein attenuated inflammation, and reduced bacterial load in lung of infected mice. Together, these findings demonstrate that TLT2 negatively regulates Th1 response against mycobacterial infection, which promotes IL-6 production through JAK/STAT3 signal pathway.
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Affiliation(s)
- Jinai Li
- Center for Infection and Immunity, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, China.,Guangdong Provincial Engineering Research Center of Molecular Imaging, Guangdong Provincial Key Laboratory of Biomedical Imaging, Department of Interventional Medicine, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, China
| | - Can Cao
- Center for Infection and Immunity, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, China.,Guangdong Provincial Engineering Research Center of Molecular Imaging, Guangdong Provincial Key Laboratory of Biomedical Imaging, Department of Interventional Medicine, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, China
| | - Yali Xiang
- Center for Infection and Immunity, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, China
| | - Zhongsi Hong
- Center for Infection and Immunity, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, China.,Guangdong Provincial Engineering Research Center of Molecular Imaging, Guangdong Provincial Key Laboratory of Biomedical Imaging, Department of Interventional Medicine, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, China
| | - Duanman He
- The Third People's Hospital of Shantou, Shantou, China
| | - Haibo Zhong
- The Third People's Hospital of Shantou, Shantou, China
| | - Ye Liu
- Center for Infection and Immunity, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, China.,Guangdong Provincial Engineering Research Center of Molecular Imaging, Guangdong Provincial Key Laboratory of Biomedical Imaging, Department of Interventional Medicine, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, China
| | - Yongjian Wu
- Center for Infection and Immunity, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, China.,Guangdong Provincial Engineering Research Center of Molecular Imaging, Guangdong Provincial Key Laboratory of Biomedical Imaging, Department of Interventional Medicine, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, China
| | - Xiaobin Zheng
- Center for Infection and Immunity, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, China.,Guangdong Provincial Engineering Research Center of Molecular Imaging, Guangdong Provincial Key Laboratory of Biomedical Imaging, Department of Interventional Medicine, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, China
| | - Huan Yin
- Center for Infection and Immunity, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, China.,Guangdong Provincial Engineering Research Center of Molecular Imaging, Guangdong Provincial Key Laboratory of Biomedical Imaging, Department of Interventional Medicine, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, China
| | - Jie Zhou
- Foshan Fourth People's Hospital, Foshan, China
| | - Hanbin Xie
- The Third People's Hospital of Shantou, Shantou, China
| | - Xi Huang
- Center for Infection and Immunity, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, China.,Guangdong Provincial Engineering Research Center of Molecular Imaging, Guangdong Provincial Key Laboratory of Biomedical Imaging, Department of Interventional Medicine, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, China
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Gabr M, Rehman AU, Chen HF. Quinoline-Pyrazole Scaffold as a Novel Ligand of Galectin-3 and Suppressor of TREM2 Signaling. ACS Med Chem Lett 2020; 11:1759-1765. [PMID: 32944144 DOI: 10.1021/acsmedchemlett.0c00330] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 08/11/2020] [Indexed: 12/20/2022] Open
Abstract
Galectin-3 has been identified as a critical player in driving the neuroinflammatory responses in Alzheimer's disease (AD). A key feature of this function of galectin-3 is associated with its interaction with the triggering receptor expressed on myeloid cells-2 (TREM2). Herein, we report a high-throughput screening (HTS) platform that can be used for the identification of inhibitors of TREM2 and galectin-3 interaction. We have utilized this HTS assay to screen a focused library of compounds optimized for the central nervous system (CNS)-related diseases. MG-257 was identified from this screen as the first example of a small molecule that can attenuate TREM2 signaling based on its high affinity to galectin-3 (endogenous ligand of TREM2). Remarkably, MG-257 reduced the levels of proinflammatory cytokines in activated microglial cells, which highlights its ability to inhibit the neuroinflammatory response associated with AD.
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Affiliation(s)
- Moustafa Gabr
- Department of Radiology, Stanford University School of Medicine, Stanford, California 94305, United States
| | - Ashfaq Ur Rehman
- Medicinal Bioinformatics Center, Shanghai Jiao Tong University School of Medicine (SJTU-SM), Shanghai 200025, China
- State Key Laboratory of Microbial Metabolism, Department of Bioinformatics and Biostatistics, National Experimental Teaching Center for Life Sciences and Biotechnology, College of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Hai-Feng Chen
- State Key Laboratory of Microbial Metabolism, Department of Bioinformatics and Biostatistics, National Experimental Teaching Center for Life Sciences and Biotechnology, College of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
- Shanghai Center for Bioinformation Technology, Shanghai 200235, China
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