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Wenzel TJ, Desjarlais JD, Mousseau DD. Human brain organoids containing microglia that have arisen innately adapt to a β-amyloid challenge better than those in which microglia are integrated by co-culture. Stem Cell Res Ther 2024; 15:258. [PMID: 39135132 PMCID: PMC11320858 DOI: 10.1186/s13287-024-03876-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Accepted: 08/01/2024] [Indexed: 08/15/2024] Open
Abstract
BACKGROUND Alzheimer disease (AD) is a heterogenous and multifactorial disease, and its pathology is partly driven by microglia and their activated phenotype. Brain organoids (BOs) are gaining prominence as a relevant model of the human brain for the study of AD; however, BOs are commonly devoid of microglia. To overcome this limitation, current protocols incorporate microglia through either (1) co-culture (BO co-culture), or (2) molecular manipulation at critical windows of BO development to have microglia arise innately (BO innate cultures). It is currently unclear whether the microglia incorporated into BOs by either of these two protocols differ in function. METHODS At in vitro day 90, BO innate cultures and BO-co-cultures were challenged with the AD-related β-amyloid peptide (Aβ) for up to 72 h. After Aβ challenge, BOs were collected for immunoblotting. Immunoblots compared immunodensity and protein banding of Aβ and ionized calcium-binding adapter molecule 1 (IBA1, a marker of microglial activation) in BOs. The translational potential of these observations was supported using 56 human cortical samples from neurocognitively normal donors and patients with early-onset AD and late-onset AD. Statistical analyses were conducted using the Kruskal-Wallis test, a two-way ANOVA, or a simple linear regression, and where applicable, followed by Dunn's or Sidak's test. RESULTS We show that BO co-cultures promote Aβ oligomerization as early as 24 h and this coincides with a significant increase in IBA1 levels. In contrast, the Aβs do not oligomerize in BO innate cultures and the IBA1 response was modest and only emerged after 48 h. In human cortical samples, we found IBA1 levels correlated with age at onset, age at death, and the putative diagnostic Aβ(1-42)/Aβ(1-40) ratio (particularly in their oligomeric forms) in a sex-dependent manner. CONCLUSIONS Our unique observations suggest that BOs with innate microglia model the response of a healthy brain to Aβ, and by extension the initial stages of Aβ challenge. It would be impossible to model these early stages of pathogenesis in BOs where microglia are already compromised, such as those with microglia incorporated by co-culture.
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Affiliation(s)
- Tyler J Wenzel
- Cell Signalling Laboratory, Department of Psychiatry, College of Medicine, University of Saskatchewan, 107 Wiggins Road, Saskatoon, SK, S7N 5E5, Canada.
| | - Joseph D Desjarlais
- Cell Signalling Laboratory, Department of Psychiatry, College of Medicine, University of Saskatchewan, 107 Wiggins Road, Saskatoon, SK, S7N 5E5, Canada
| | - Darrell D Mousseau
- Cell Signalling Laboratory, Department of Psychiatry, College of Medicine, University of Saskatchewan, 107 Wiggins Road, Saskatoon, SK, S7N 5E5, Canada
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2
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Tan AYS, Tippett LJ, Turner CP, Swanson MEV, Park TIH, Curtis MA, Faull RLM, Dragunow M, Singh-Bains MK. Microglial proliferation and astrocytic protein alterations in the human Huntington's disease cortex. Neurobiol Dis 2024; 198:106554. [PMID: 38844243 DOI: 10.1016/j.nbd.2024.106554] [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: 03/20/2024] [Revised: 05/28/2024] [Accepted: 06/03/2024] [Indexed: 06/14/2024] Open
Abstract
Huntington's disease (HD) is a neurodegenerative disorder that severely affects the basal ganglia and regions of the cerebral cortex. While astrocytosis and microgliosis both contribute to basal ganglia pathology, the contribution of gliosis and potential factors driving glial activity in the human HD cerebral cortex is less understood. Our study aims to identify nuanced indicators of gliosis in HD which is challenging to identify in the severely degenerated basal ganglia, by investigating the middle temporal gyrus (MTG), a cortical region previously documented to demonstrate milder neuronal loss. Immunohistochemistry was conducted on MTG paraffin-embedded tissue microarrays (TMAs) comprising 29 HD and 35 neurologically normal cases to compare the immunoreactivity patterns of key astrocytic proteins (glial fibrillary acidic protein, GFAP; inwardly rectifying potassium channel 4.1, Kir4.1; glutamate transporter-1, GLT-1; aquaporin-4, AQP4), key microglial proteins (ionised calcium-binding adapter molecule-1, IBA-1; human leukocyte antigen (HLA)-DR; transmembrane protein 119, TMEM119; purinergic receptor P2RY12, P2RY12), and indicators of proliferation (Ki-67; proliferative cell nuclear antigen, PCNA). Our findings demonstrate an upregulation of GFAP+ protein expression attributed to the presence of more GFAP+ expressing cells in HD, which correlated with greater cortical mutant huntingtin (mHTT) deposition. In contrast, Kir4.1, GLT-1, and AQP4 immunoreactivity levels were unchanged in HD. We also demonstrate an increased number of IBA-1+ and TMEM119+ microglia with somal enlargement. IBA-1+, TMEM119+, and P2RY12+ reactive microglia immunophenotypes were also identified in HD, evidenced by the presence of rod-shaped, hypertrophic, and dystrophic microglia. In HD cases, IBA-1+ cells contained either Ki-67 or PCNA, whereas GFAP+ astrocytes were devoid of proliferative nuclei. These findings suggest cortical microgliosis may be driven by proliferation in HD, supporting the hypothesis of microglial proliferation as a feature of HD pathophysiology. In contrast, astrocytes in HD demonstrate an altered GFAP expression profile that is associated with the degree of mHTT deposition.
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Affiliation(s)
- Adelie Y S Tan
- Centre for Brain Research, University of Auckland, Auckland 1023, New Zealand; Department of Anatomy and Medical Imaging, University of Auckland, Auckland 1023, New Zealand
| | - Lynette J Tippett
- Centre for Brain Research, University of Auckland, Auckland 1023, New Zealand; School of Psychology, University of Auckland, Auckland 1023, New Zealand
| | - Clinton P Turner
- Centre for Brain Research, University of Auckland, Auckland 1023, New Zealand; Department of Anatomical Pathology, LabPlus, Auckland City Hospital, Auckland 1023, New Zealand
| | - Molly E V Swanson
- Centre for Brain Research, University of Auckland, Auckland 1023, New Zealand; School of Biological Sciences, University of Auckland, Auckland 1023, New Zealand
| | - Thomas I H Park
- Centre for Brain Research, University of Auckland, Auckland 1023, New Zealand; Department of Pharmacology and Clinical Pharmacology, University of Auckland, Auckland 1023, New Zealand
| | - Maurice A Curtis
- Centre for Brain Research, University of Auckland, Auckland 1023, New Zealand; Department of Anatomy and Medical Imaging, University of Auckland, Auckland 1023, New Zealand
| | - Richard L M Faull
- Centre for Brain Research, University of Auckland, Auckland 1023, New Zealand; Department of Anatomy and Medical Imaging, University of Auckland, Auckland 1023, New Zealand
| | - Mike Dragunow
- Centre for Brain Research, University of Auckland, Auckland 1023, New Zealand; Department of Pharmacology and Clinical Pharmacology, University of Auckland, Auckland 1023, New Zealand.
| | - Malvindar K Singh-Bains
- Centre for Brain Research, University of Auckland, Auckland 1023, New Zealand; Department of Anatomy and Medical Imaging, University of Auckland, Auckland 1023, New Zealand.
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Wang Y, Bai M, Wang X, Peng Z, Cai C, Xi J, Yan C, Luo J, Li X. Gastrodin: a comprehensive pharmacological review. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2024; 397:3781-3802. [PMID: 38165423 DOI: 10.1007/s00210-023-02920-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Accepted: 12/21/2023] [Indexed: 01/03/2024]
Abstract
Tianma is the dried tuber of Gastrodia elata Blume (G. elata), which is frequently utilized in clinical practice as a traditional Chinese medicine. Gastrodin (GAS) is the main active ingredient of Tianma, which has good pharmacological activity. Therefore, for the first time, this review focused on the extraction, synthesis, pharmacological effects, and derivatives of GAS and to investigate additional development options for GAS. The use of microorganisms to create GAS is a promising method. GAS has good efficacy in the treatment of neurological diseases, cardiovascular diseases, endocrine diseases, and liver diseases. GAS has significant anti-inflammatory, antioxidant, neuroprotective, vascular protective, blood sugar lowering, lipid-regulating, analgesic, anticancer, and antiviral effects. The mechanism involves various signaling pathways such as Nrf2, NF-κB, PI3K/AKT, and AMPK. In addition, the derivatives of GAS and biomaterials synthesized by GAS and PU suggested a broader application of GAS. The research on GAS is thoroughly summarized in this paper, which has useful applications for tackling a variety of disorders and exhibits good development value.
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Affiliation(s)
- Yulin Wang
- State Key Laboratory of Southwestern Chinese Medicine Resources, Chengdu University of Traditional Chinese Medicine, Chengdu, China
- School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China
| | - Mengting Bai
- State Key Laboratory of Southwestern Chinese Medicine Resources, Chengdu University of Traditional Chinese Medicine, Chengdu, China
- School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China
| | - Xian Wang
- State Key Laboratory of Southwestern Chinese Medicine Resources, Chengdu University of Traditional Chinese Medicine, Chengdu, China
- School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China
| | - Zhaolei Peng
- State Key Laboratory of Southwestern Chinese Medicine Resources, Chengdu University of Traditional Chinese Medicine, Chengdu, China
- School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China
| | - Chunyan Cai
- State Key Laboratory of Southwestern Chinese Medicine Resources, Chengdu University of Traditional Chinese Medicine, Chengdu, China
- School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China
| | - Jingjing Xi
- State Key Laboratory of Southwestern Chinese Medicine Resources, Chengdu University of Traditional Chinese Medicine, Chengdu, China
- School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China
| | - Chunmei Yan
- State Key Laboratory of Southwestern Chinese Medicine Resources, Chengdu University of Traditional Chinese Medicine, Chengdu, China
- School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China
| | - Jia Luo
- State Key Laboratory of Southwestern Chinese Medicine Resources, Chengdu University of Traditional Chinese Medicine, Chengdu, China.
- School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China.
| | - Xiaofang Li
- State Key Laboratory of Southwestern Chinese Medicine Resources, Chengdu University of Traditional Chinese Medicine, Chengdu, China.
- School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China.
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Grewal S, Gonçalves de Andrade E, Kofoed RH, Matthews PM, Aubert I, Tremblay MÈ, Morse SV. Using focused ultrasound to modulate microglial structure and function. Front Cell Neurosci 2023; 17:1290628. [PMID: 38164436 PMCID: PMC10757935 DOI: 10.3389/fncel.2023.1290628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Accepted: 10/31/2023] [Indexed: 01/03/2024] Open
Abstract
Transcranial focused ultrasound (FUS) has the unique ability to target regions of the brain with high spatial precision, in a minimally invasive manner. Neuromodulation studies have shown that FUS can excite or inhibit neuronal activity, demonstrating its tremendous potential to improve the outcome of neurological diseases. Recent evidence has also shed light on the emerging promise that FUS has, with and without the use of intravenously injected microbubbles, in modulating the blood-brain barrier and the immune cells of the brain. As the resident immune cells of the central nervous system, microglia are at the forefront of the brain's maintenance and immune defense. Notably, microglia are highly dynamic and continuously survey the brain parenchyma by extending and retracting their processes. This surveillance activity aids microglia in performing key physiological functions required for brain activity and plasticity. In response to stressors, microglia rapidly alter their cellular and molecular profile to help facilitate a return to homeostasis. While the underlying mechanisms by which both FUS and FUS + microbubbles modify microglial structure and function remain largely unknown, several studies in adult mice have reported changes in the expression of the microglia/macrophage marker ionized calcium binding adaptor molecule 1, and in their phagocytosis, notably of protein aggregates, such as amyloid beta. In this review, we discuss the demonstrated and putative biological effects of FUS and FUS + microbubbles in modulating microglial activities, with an emphasis on the key cellular and molecular changes observed in vitro and in vivo across models of brain health and disease. Understanding how this innovative technology can modulate microglia paves the way for future therapeutic strategies aimed to promote beneficial physiological microglial roles, and prevent or treat maladaptive responses.
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Affiliation(s)
- Sarina Grewal
- Department of Bioengineering, Imperial College London, London, United Kingdom
- Department of Brain Sciences, Imperial College London, London, United Kingdom
| | - Elisa Gonçalves de Andrade
- Neuroscience Graduate Program, Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
| | - Rikke Hahn Kofoed
- Department of Neurosurgery, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
- Center for Experimental Neuroscience-CENSE, Department of Neurosurgery, Aarhus University Hospital, Aarhus, Denmark
- Hurvitz Brain Sciences Research Program, Biological Sciences, Sunnybrook Research Institute, Toronto, ON, Canada
| | - Paul M. Matthews
- Department of Brain Sciences, Imperial College London, London, United Kingdom
- UK Dementia Research Institute, Imperial College London, London, United Kingdom
| | - Isabelle Aubert
- Hurvitz Brain Sciences Research Program, Biological Sciences, Sunnybrook Research Institute, Toronto, ON, Canada
- Department of Laboratory Medicine and Pathobiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Marie-Ève Tremblay
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
- Axe Neurosciences, Centre de recherche du CHU de Québec-Université Laval, Québec, QC, Canada
- Department of Molecular Medicine, Université Laval, Québec, QC, Canada
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC, Canada
| | - Sophie V. Morse
- Department of Bioengineering, Imperial College London, London, United Kingdom
- UK Dementia Research Institute, Imperial College London, London, United Kingdom
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Ennerfelt H, Holliday C, Shapiro D, Zengeler K, Bolte A, Ulland T, Lukens J. CARD9 attenuates Aβ pathology and modifies microglial responses in an Alzheimer's disease mouse model. Proc Natl Acad Sci U S A 2023; 120:e2303760120. [PMID: 37276426 PMCID: PMC10268238 DOI: 10.1073/pnas.2303760120] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Accepted: 04/04/2023] [Indexed: 06/07/2023] Open
Abstract
Recent advances have highlighted the importance of several innate immune receptors expressed by microglia in Alzheimer's disease (AD). In particular, mounting evidence from AD patients and experimental models indicates pivotal roles for TREM2, CD33, and CD22 in neurodegenerative disease progression. While there is growing interest in targeting these microglial receptors to treat AD, we still lack knowledge of the downstream signaling molecules used by these receptors to orchestrate immune responses in AD. Notably, TREM2, CD33, and CD22 have been described to influence signaling associated with the intracellular adaptor molecule CARD9 to mount downstream immune responses outside of the brain. However, the role of CARD9 in AD remains poorly understood. Here, we show that genetic ablation of CARD9 in the 5xFAD mouse model of AD results in exacerbated amyloid beta (Aβ) deposition, increased neuronal loss, worsened cognitive deficits, and alterations in microglial responses. We further show that pharmacological activation of CARD9 promotes improved clearance of Aβ deposits from the brains of 5xFAD mice. These results help to establish CARD9 as a key intracellular innate immune signaling molecule that regulates Aβ-mediated disease and microglial responses. Moreover, these findings suggest that targeting CARD9 might offer a strategy to improve Aβ clearance in AD.
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Affiliation(s)
- Hannah Ennerfelt
- Department of Neuroscience, Center for Brain Immunology and Glia, University of Virginia, Charlottesville, VA22908
- Neuroscience Graduate Program, University of Virginia, Charlottesville, VA22908
- Cell and Molecular Biology Graduate Training Program, University of Virginia, Charlottesville, VA22908
| | - Coco Holliday
- Department of Neuroscience, Center for Brain Immunology and Glia, University of Virginia, Charlottesville, VA22908
| | - Daniel A. Shapiro
- Department of Neuroscience, Center for Brain Immunology and Glia, University of Virginia, Charlottesville, VA22908
| | - Kristine E. Zengeler
- Department of Neuroscience, Center for Brain Immunology and Glia, University of Virginia, Charlottesville, VA22908
- Neuroscience Graduate Program, University of Virginia, Charlottesville, VA22908
- Cell and Molecular Biology Graduate Training Program, University of Virginia, Charlottesville, VA22908
| | - Ashley C. Bolte
- Department of Neuroscience, Center for Brain Immunology and Glia, University of Virginia, Charlottesville, VA22908
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia, Charlottesville, VA22908
- Medical Scientist Training Program, University of Virginia, Charlottesville, VA22908
| | - Tyler K. Ulland
- Department of Pathology and Laboratory Medicine, University of Wisconsin, Madison, WI53705
| | - John R. Lukens
- Department of Neuroscience, Center for Brain Immunology and Glia, University of Virginia, Charlottesville, VA22908
- Neuroscience Graduate Program, University of Virginia, Charlottesville, VA22908
- Cell and Molecular Biology Graduate Training Program, University of Virginia, Charlottesville, VA22908
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia, Charlottesville, VA22908
- Medical Scientist Training Program, University of Virginia, Charlottesville, VA22908
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6
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Edler MK, Munger EL, Maycon H, Hopkins WD, Hof PR, Sherwood CC, Raghanti MA. The association of astrogliosis and microglial activation with aging and Alzheimer's disease pathology in the chimpanzee brain. J Neurosci Res 2023; 101:881-900. [PMID: 36647571 DOI: 10.1002/jnr.25167] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 10/31/2022] [Accepted: 12/30/2022] [Indexed: 01/18/2023]
Abstract
Aging and neurodegenerative disorders, such as Alzheimer's disease (AD), trigger an immune response known as glial activation in the brain. Recent evidence indicates species differences in inflammatory responses to AD pathology, highlighting the need for additional comparative studies to further understand human-specific neuropathologies. In the present study, we report on the occurrence of astrogliosis, microglial activation, and their relationship with age and AD-like pathology in a cohort of male and female chimpanzees (Pan troglodytes). Chimpanzees with severe astrogliosis exhibited widespread upregulation of hypertrophic astrocytes immunoreactive for glial fibrillary acidic protein (GFAP) throughout all layers of the dorsolateral prefrontal cortex and a loss of the interlaminar palisade. In addition, extreme astrogliosis was associated with increased astrocyte density in the absence of significant microglial activation and AD lesions. A shift from decreased resting to increased phagocytotic microglia occurred with aging, although proliferation was absent and no changes in astrogliosis was observed. Vascular amyloid correlated with decreased astrocyte and microglia densities, while tau lesions were associated with morphological changes in microglia and greater total glia density and glia: neuron ratio. These results further our understanding of inflammatory processes within the chimpanzee brain and provide comparative data to improve our understanding of human aging and neuropathological processes.
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Affiliation(s)
- Melissa K Edler
- Department of Anthropology, School of Biomedical Sciences, and Brain Health Research Institute, Kent State University, Kent, Ohio, USA
| | - Emily L Munger
- Department of Anthropology, School of Biomedical Sciences, and Brain Health Research Institute, Kent State University, Kent, Ohio, USA
| | - Hannah Maycon
- Department of Anthropology, School of Biomedical Sciences, and Brain Health Research Institute, Kent State University, Kent, Ohio, USA
| | - William D Hopkins
- Department of Comparative Medicine, University of Texas MD Anderson Cancer Center, Bastrop, Texas, USA
| | - Patrick R Hof
- Nash Family Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Chet C Sherwood
- Department of Anthropology and Center for the Advanced Study of Human Paleobiology, The George Washington University, Washington, District of Columbia, USA
| | - Mary Ann Raghanti
- Department of Anthropology, School of Biomedical Sciences, and Brain Health Research Institute, Kent State University, Kent, Ohio, USA
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Microglial Expression of the Wnt Signaling Modulator DKK2 Differs between Human Alzheimer's Disease Brains and Mouse Neurodegeneration Models. eNeuro 2023; 10:ENEURO.0306-22.2022. [PMID: 36599670 PMCID: PMC9836029 DOI: 10.1523/eneuro.0306-22.2022] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Revised: 12/12/2022] [Accepted: 12/13/2022] [Indexed: 01/05/2023] Open
Abstract
Wnt signaling is crucial for synapse and cognitive function. Indeed, deficient Wnt signaling is causally related to increased expression of DKK1, an endogenous negative Wnt regulator, and synapse loss, both of which likely contribute to cognitive decline in Alzheimer's disease (AD). Increasingly, AD research efforts have probed the neuroinflammatory role of microglia, the resident immune cells of the CNS, which have furthermore been shown to be modulated by Wnt signaling. The DKK1 homolog DKK2 has been previously identified as an activated response and/or disease-associated microglia (DAM/ARM) gene in a mouse model of AD. Here, we performed a detailed analysis of DKK2 in mouse models of neurodegeneration, and in human AD brain. In APP/PS1 and APPNL-G-F AD mouse model brains as well as in SOD1G93A ALS mouse model spinal cords, but not in control littermates, we demonstrated significant microgliosis and microglial Dkk2 mRNA upregulation in a disease-stage-dependent manner. In the AD models, these DAM/ARM Dkk2+ microglia preferentially accumulated close to βAmyloid plaques. Furthermore, recombinant DKK2 treatment of rat hippocampal primary neurons blocked WNT7a-induced dendritic spine and synapse formation, indicative of an anti-synaptic effect similar to that of DKK1. In stark contrast, no such microglial DKK2 upregulation was detected in the postmortem human frontal cortex from individuals diagnosed with AD or pathologic aging. In summary, the difference in microglial expression of the DAM/ARM gene DKK2 between mouse models and human AD brain highlights the increasingly recognized limitations of using mouse models to recapitulate facets of human neurodegenerative disease.
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Stopschinski BE, Weideman RA, McMahan D, Jacob DA, Little BB, Chiang HS, Saez Calveras N, Stuve O. Microglia as a cellular target of diclofenac therapy in Alzheimer's disease. Ther Adv Neurol Disord 2023; 16:17562864231156674. [PMID: 36875711 PMCID: PMC9974624 DOI: 10.1177/17562864231156674] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Accepted: 01/26/2023] [Indexed: 03/07/2023] Open
Abstract
Alzheimer's disease (AD) is an untreatable cause of dementia, and new therapeutic approaches are urgently needed. AD pathology is defined by extracellular amyloid plaques and intracellular neurofibrillary tangles. Research of the past decades has suggested that neuroinflammation plays a critical role in the pathophysiology of AD. This has led to the idea that anti-inflammatory treatments might be beneficial. Early studies investigated non-steroidal anti-inflammatory drugs (NSAIDS) such as indomethacin, celecoxib, ibuprofen, and naproxen, which had no benefit. More recently, protective effects of diclofenac and NSAIDs in the fenamate group have been reported. Diclofenac decreased the frequency of AD significantly compared to other NSAIDs in a large retrospective cohort study. Diclofenac and fenamates share similar chemical structures, and evidence from cell and mouse models suggests that they inhibit the release of pro-inflammatory mediators from microglia with leads to the reduction of AD pathology. Here, we review the potential role of diclofenac and NSAIDs in the fenamate group for targeting AD pathology with a focus on its potential effects on microglia.
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Affiliation(s)
- Barbara E Stopschinski
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas, TX, USA.,Center for Alzheimer's and Neurodegenerative Diseases, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | | | - Danni McMahan
- Pharmacy Service, Dallas VA Medical Center, Dallas, TX, USA
| | - David A Jacob
- Veterans Integrated Service Network 17, Arlington, TX, USA
| | - Bertis B Little
- School of Public Health and Information Sciences, University of Louisville, Louisville, KY, USA
| | - Hsueh-Sheng Chiang
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Nil Saez Calveras
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Olaf Stuve
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas, TX, USA.,Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA.,Neurology Section, Dallas VA Medical Center, 4500 South Lancaster Road, Dallas, TX 75216, USA
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9
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Wan Chik M, Ramli NA, Mohamad Nor Hazalin NA, Surindar Singh GK. Streptozotocin mechanisms and its role in rodent models for Alzheimer’s disease. TOXIN REV 2022. [DOI: 10.1080/15569543.2022.2150646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Mazzura Wan Chik
- Department of Pharmaceutical Life Sciences, Faculty of Pharmacy, Universiti Teknologi MARA (UiTM), Selangor, Malaysia
| | - Nur Adiilah Ramli
- Department of Pharmaceutical Life Sciences, Faculty of Pharmacy, Universiti Teknologi MARA (UiTM), Selangor, Malaysia
| | - Nurul Aqmar Mohamad Nor Hazalin
- Department of Pharmaceutical Life Sciences, Faculty of Pharmacy, Universiti Teknologi MARA (UiTM), Selangor, Malaysia
- Integrative Pharmacogenomics Institute (iPROMiSE), Level 7, FF3, Universiti Teknologi MARA, Selangor, Malaysia
| | - Gurmeet Kaur Surindar Singh
- Department of Pharmaceutical Life Sciences, Faculty of Pharmacy, Universiti Teknologi MARA (UiTM), Selangor, Malaysia
- Brain Degeneration and Therapeutics Group, Universiti Teknologi MARA (UiTM), 40450 Shah Alam, Selangor, Malaysia
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10
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St-Pierre MK, VanderZwaag J, Loewen S, Tremblay MÈ. All roads lead to heterogeneity: The complex involvement of astrocytes and microglia in the pathogenesis of Alzheimer’s disease. Front Cell Neurosci 2022; 16:932572. [PMID: 36035256 PMCID: PMC9413962 DOI: 10.3389/fncel.2022.932572] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 07/11/2022] [Indexed: 01/04/2023] Open
Abstract
In recent years, glial cells have been acknowledged as key players in the pathogenesis of Alzheimer’s disease (AD), a neurodegenerative condition in which an accumulation of intracellular neurofibrillary tangles and extracellular fibrillar amyloid beta is notably observed in the central nervous system. Genome-wide association studies have shown, both in microglia and astrocytes, an increase in gene variants associated with a higher risk of developing late-onset AD. Microglia, the resident innate immune cells of the brain, and astrocytes, glial cells crucial for vascular integrity and neuronal support, both agglomerate near amyloid beta plaques and dystrophic neurites where they participate in the elimination of these harmful parenchymal elements. However, their role in AD pathogenesis has been challenging to resolve due to the highly heterogeneous nature of these cell populations, i.e., their molecular, morphological, and ultrastructural diversity, together with their ever-changing responsiveness and functions throughout the pathological course of AD. With the recent expansions in the field of glial heterogeneity through innovative advances in state-of-the-art microscopy and -omics techniques, novel concepts and questions arose, notably pertaining to how the diverse microglial and astrocytic states interact with each other and with the AD hallmarks, and how their concerted efforts/actions impact the progression of the disease. In this review, we discuss the recent advances and findings on the topic of glial heterogeneity, particularly focusing on the relationships of these cells with AD hallmarks (e.g., amyloid beta plaques, neurofibrillary tangles, synaptic loss, and dystrophic neurites) in murine models of AD pathology and post-mortem brain samples of patients with AD.
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Affiliation(s)
- Marie-Kim St-Pierre
- Département de Médecine Moléculaire, Université Laval, Quebec City, QC, Canada
- Axe Neurosciences, Center de Recherche du CHU de Québec, Université Laval, Quebec City, QC, Canada
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
| | - Jared VanderZwaag
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
- Neuroscience Graduate Program, University of Victoria, Victoria, BC, Canada
| | - Sophia Loewen
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
- Department of Biology, University of Victoria, Victoria, BC, Canada
| | - Marie-Ève Tremblay
- Département de Médecine Moléculaire, Université Laval, Quebec City, QC, Canada
- Axe Neurosciences, Center de Recherche du CHU de Québec, Université Laval, Quebec City, QC, Canada
- Division of Medical Sciences, University of Victoria, Victoria, BC, Canada
- Neurology and Neurosurgery Department, McGill University, Montréal, QC, Canada
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC, Canada
- Center for Advanced Materials and Related Technology (CAMTEC), University of Victoria, Victoria, BC, Canada
- *Correspondence: Marie-Ève Tremblay,
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11
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Galea E, Weinstock LD, Larramona-Arcas R, Pybus AF, Giménez-Llort L, Escartin C, Wood LB. Multi-transcriptomic analysis points to early organelle dysfunction in human astrocytes in Alzheimer's disease. Neurobiol Dis 2022; 166:105655. [PMID: 35143967 PMCID: PMC9504227 DOI: 10.1016/j.nbd.2022.105655] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 01/10/2022] [Accepted: 02/04/2022] [Indexed: 12/11/2022] Open
Abstract
The phenotypic transformation of astrocytes in Alzheimer's disease (AD) is still not well understood. Recent analyses based on single-nucleus RNA sequencing of postmortem Alzheimer's disease (AD) samples are limited by the low number of sequenced astrocytes, small cohort sizes, and low number of differentially expressed genes detected. To optimize the detection of astrocytic genes, we employed a novel strategy consisting of the localization of pre-determined astrocyte and neuronal gene clusters in publicly available whole-brain transcriptomes. Specifically, we used cortical transcriptomes from 766 individuals, including cognitively normal subjects (Controls), and people diagnosed with mild cognitive impairment (MCI) or dementia due to AD. Samples came from three independent cohorts organized by the Mount Sinai Hospital, the Mayo Clinic, and the Religious Order Study/Memory and Aging Project (ROSMAP). Astrocyte- and neuron-specific gene clusters were generated from human brain cell-type specific RNAseq data using hierarchical clustering and cell-type enrichment scoring. Genes from each cluster were manually annotated according to cell-type specific functional Categories. Gene Set Variation Analysis (GSVA) and Principal Component Analysis (PCA) were used to establish changes in these functional categories among clinical cohorts. We highlight three novel findings of the study. First, individuals with the same clinical diagnosis were molecularly heterogeneous. Particularly in the Mayo Clinic and ROSMAP cohorts, over 50% of Controls presented down-regulation of genes encoding synaptic proteins typical of AD, whereas 30% of patients diagnosed with dementia due to AD presented Control-like transcriptomic profiles. Second, down-regulation of neuronal genes related to synaptic proteins coincided, in astrocytes, with up-regulation of genes related to perisynaptic astrocytic processes (PAP) and down-regulation of genes encoding endolysosomal and mitochondrial proteins. Third, down-regulation of astrocytic mitochondrial genes inversely correlated with the disease stages defined by Braak and CERAD scoring. Finally, we interpreted these changes as maladaptive or adaptive from the point of view of astrocyte biology in a model of the phenotypical transformation of astrocytes in AD. The main prediction is that early malfunction of the astrocytic endolysosomal system, associated with progressive mitochondrial dysfunction, contribute to Alzheimer's disease. If this prediction is correct, therapies preventing organelle dysfunction in astrocytes may be beneficial in preclinical and clinical AD.
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Affiliation(s)
- Elena Galea
- Institut de Neurociències, Universitat Autònoma de Barcelona, Bellaterra 08193, Barcelona, Spain; Departament de Bioquímica, Unitat de Bioquímica, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain; ICREA, 08010 Barcelona, Spain.
| | - Laura D Weinstock
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta 30332, USA
| | - Raquel Larramona-Arcas
- Institut de Neurociències, Universitat Autònoma de Barcelona, Bellaterra 08193, Barcelona, Spain; Departament de Bioquímica, Unitat de Bioquímica, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain
| | - Alyssa F Pybus
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta 30332, USA
| | - Lydia Giménez-Llort
- Institut de Neurociències, Universitat Autònoma de Barcelona, Bellaterra 08193, Barcelona, Spain; Departament de Psiquiatria i Medicina Forense, Universitat Autònoma de Barcelona, Bellaterra 08193, Barcelona, Spain
| | - Carole Escartin
- Université Paris-Saclay, CEA, CNRS, MIRCen, Laboratoire des Maladies Neurodégénératives, 92265 Fontenay-aux-Roses, France
| | - Levi B Wood
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta 30332, USA; George W. Woodruff School of Mechanical Engineering and Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta 30332, USA.
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12
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Guan Y, Zhang L, Wang S, Deng Y, Zhou H, Chen D, Zhang L. The role of microglia in Alzheimer's disease and progress of treatment. IBRAIN 2022; 8:37-47. [PMID: 37786418 PMCID: PMC10529349 DOI: 10.1002/ibra.12023] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 01/25/2022] [Indexed: 10/04/2023]
Abstract
Microglia are permanent immune cells of the central nervous system. Microglia play an important role in the pathological process of Alzheimer's disease (AD). They are mainly involved in the uptake and clearance of amyloid-β (Aβ), as well as the formation of neuroinflammation. We found that overactivated microglia increase Aβ and Tau, and Aβ and Tau in turn act as activators of microglia. Additionally, various cytokines and proteins, high cholesterol, and telomere shortening are all associated with microglia activation. More activated microglia induce the release of inflammatory and anti-inflammatory factors to regulate inflammation, while microglia express multiple homologous receptors that bind to neuroimmunomodulators to prevent microglia overactivation. Moreover, aging of the body promotes neuroinflammation by increasing the response to IFN-γ (interferon-γ), and aging of the microglia themselves promotes AD by inducing the accumulation of large amounts of iron and reducing autophagy by regulating protein levels. Cognitive dysfunction occurs when activated microglia induce an increase in beta oligomers, promoting the production of pro-inflammatory factors that alter the shape, composition, and density of synapses. Based on their correlation, microglia-mediated AD therapy as well as the corresponding targets and drugs are discussed. In contrast to similar reviews, this article also summarizes some novel microglia-mediated AD treatment methods over the recent years.
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Affiliation(s)
- Yi‐Huan Guan
- Department of AnesthesiologyZunyi Medical UniversityZunyiGuizhouChina
| | - Ling‐Jing Zhang
- Department of AnesthesiologyZunyi Medical UniversityZunyiGuizhouChina
| | - Shi‐Ya Wang
- Department of AnesthesiologyZunyi Medical UniversityZunyiGuizhouChina
| | - Ya‐Dan Deng
- Department of AnesthesiologyZunyi Medical UniversityZunyiGuizhouChina
| | - Hong‐Su Zhou
- Department of AnesthesiaGraduate School of Zunyi Medical UniversityZunyiGuizhouChina
| | - Dong‐Qing Chen
- Department of AnesthesiaGraduate School of Zunyi Medical UniversityZunyiGuizhouChina
| | - Lan‐Chun Zhang
- Department of ZoologyKunming Medical UniversityKunmingChina
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13
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Garland EF, Hartnell IJ, Boche D. Microglia and Astrocyte Function and Communication: What Do We Know in Humans? Front Neurosci 2022; 16:824888. [PMID: 35250459 PMCID: PMC8888691 DOI: 10.3389/fnins.2022.824888] [Citation(s) in RCA: 47] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Accepted: 01/24/2022] [Indexed: 12/11/2022] Open
Abstract
Microglia and astrocytes play essential roles in the central nervous system contributing to many functions including homeostasis, immune response, blood–brain barrier maintenance and synaptic support. Evidence has emerged from experimental models of glial communication that microglia and astrocytes influence and coordinate each other and their effects on the brain environment. However, due to the difference in glial cells between humans and rodents, it is essential to confirm the relevance of these findings in human brains. Here, we aim to review the current knowledge on microglia-astrocyte crosstalk in humans, exploring novel methodological techniques used in health and disease conditions. This will include an in-depth look at cell culture and iPSCs, post-mortem studies, imaging and fluid biomarkers, genetics and transcriptomic data. In this review, we will discuss the advantages and limitations of these methods, highlighting the understanding these methods have brought the field on these cells communicative abilities, and the knowledge gaps that remain.
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14
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Huang Y, Zhao M, Chen X, Zhang R, Le A, Hong M, Zhang Y, Jia L, Zang W, Jiang C, Wang J, Fan X, Wang J. Tryptophan Metabolism in Central Nervous System Diseases: Pathophysiology and Potential Therapeutic Strategies. Aging Dis 2022; 14:858-878. [PMID: 37191427 DOI: 10.14336/ad.2022.0916] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2022] [Accepted: 09/16/2022] [Indexed: 11/19/2022] Open
Abstract
The metabolism of L-tryptophan (TRP) regulates homeostasis, immunity, and neuronal function. Altered TRP metabolism has been implicated in the pathophysiology of various diseases of the central nervous system. TRP is metabolized through two main pathways, the kynurenine pathway and the methoxyindole pathway. First, TRP is metabolized to kynurenine, then kynurenic acid, quinolinic acid, anthranilic acid, 3-hydroxykynurenine, and finally 3-hydroxyanthranilic acid along the kynurenine pathway. Second, TRP is metabolized to serotonin and melatonin along the methoxyindole pathway. In this review, we summarize the biological properties of key metabolites and their pathogenic functions in 12 disorders of the central nervous system: schizophrenia, bipolar disorder, major depressive disorder, spinal cord injury, traumatic brain injury, ischemic stroke, intracerebral hemorrhage, multiple sclerosis, Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, and Huntington's disease. Furthermore, we summarize preclinical and clinical studies, mainly since 2015, that investigated the metabolic pathway of TRP, focusing on changes in biomarkers of these neurologic disorders, their pathogenic implications, and potential therapeutic strategies targeting this metabolic pathway. This critical, comprehensive, and up-to-date review helps identify promising directions for future preclinical, clinical, and translational research on neuropsychiatric disorders.
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15
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Gault N, Szele FG. Immunohistochemical evidence for adult human neurogenesis in health and disease. WIREs Mech Dis 2021; 13:e1526. [PMID: 34730290 DOI: 10.1002/wsbm.1526] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 02/03/2021] [Accepted: 02/04/2021] [Indexed: 01/19/2023]
Abstract
Postnatal and adult neurogenesis in the subventricular zone and subgranular zone of animals such as rodents and non-human primates has been observed with many different technical approaches. Since most techniques used in animals cannot be used in humans, the majority of human neurogenesis studies rely on postmortem immunohistochemistry. This technique is difficult in human tissue, due to poor and variable preservation of antigens and samples. Nevertheless, a survey of the literature reveals that most published studies provide evidence for childhood and adult neurogenesis in the human brain stem cell niches. There are some conflicting results even when assessing the same markers and when using the same antibodies. Focusing on immunohistochemical studies on post-mortem human sections, we discuss the relative robustness of the literature on adult neurogenesis. We also discuss the response of the subventricular and subgranular zones to human disease, showing that the two niches can respond differently and that the stage of disease impacts neurogenesis levels. Thus, we highlight strong evidence for adult human neurogenesis, discuss other work that did not find it, describe obstacles in analysis, and offer other approaches to evaluate the neurogenic potential of the subventricular and subgranular zones of Homo sapiens. This article is categorized under: Neurological Diseases > Stem Cells and Development Reproductive System Diseases > Stem Cells and Development.
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Affiliation(s)
| | - Francis G Szele
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, UK
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16
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Mirzaei N, Davis N, Chau TW, Sastre M. Astrocyte Reactivity in Alzheimer's Disease: Therapeutic Opportunities to Promote Repair. Curr Alzheimer Res 2021; 19:1-15. [PMID: 34719372 DOI: 10.2174/1567205018666211029164106] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 07/02/2021] [Accepted: 07/31/2021] [Indexed: 11/22/2022]
Abstract
Astrocytes are fast climbing the ladder of importance in neurodegenerative disorders, particularly in Alzheimer's disease (AD), with the prominent presence of reactive astrocytes sur- rounding amyloid β- plaques, together with activated microglia. Reactive astrogliosis, implying morphological and molecular transformations in astrocytes, seems to precede neurodegeneration, suggesting a role in the development of the disease. Single-cell transcriptomics has recently demon- strated that astrocytes from AD brains are different from "normal" healthy astrocytes, showing dys- regulations in areas such as neurotransmitter recycling, including glutamate and GABA, and im- paired homeostatic functions. However, recent data suggest that the ablation of astrocytes in mouse models of amyloidosis results in an increase in amyloid pathology as well as in the inflammatory profile and reduced synaptic density, indicating that astrocytes mediate neuroprotective effects. The idea that interventions targeting astrocytes may have great potential for AD has therefore emerged, supported by a range of drugs and stem cell transplantation studies that have successfully shown a therapeutic effect in mouse models of AD. In this article, we review the latest reports on the role and profile of astrocytes in AD brains and how manipulation of astrocytes in animal mod- els has paved the way for the use of treatments enhancing astrocytic function as future therapeutic avenues for AD.
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Affiliation(s)
- Nazanin Mirzaei
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, 127 S. San Vicente Blvd., Los Angeles, CA, 90048. United States
| | - Nicola Davis
- Department of Brain Sciences, Imperial College London, Hammer-smith Hospital, Du Cane Road, LondonW12 0NN. United Kingdom
| | - Tsz Wing Chau
- Department of Brain Sciences, Imperial College London, Hammer-smith Hospital, Du Cane Road, LondonW12 0NN. United Kingdom
| | - Magdalena Sastre
- Department of Brain Sciences, Imperial College London, Hammer-smith Hospital, Du Cane Road, LondonW12 0NN. United Kingdom
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17
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Xie L, Liu Y, Zhang N, Li C, Sandhu AF, Williams G, Shen Y, Li H, Wu Q, Yu S. Electroacupuncture Improves M2 Microglia Polarization and Glia Anti-inflammation of Hippocampus in Alzheimer's Disease. Front Neurosci 2021; 15:689629. [PMID: 34646113 PMCID: PMC8502881 DOI: 10.3389/fnins.2021.689629] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 07/30/2021] [Indexed: 11/13/2022] Open
Abstract
Background: Alzheimer's disease (AD) is a neurodegenerative disease characterized by loss of recognition and memory. Neuroinflammation plays pivotal roles in the pathology of AD and affects the progression of the disease. Astrocyte and microglia, as main immune executors in the central nervous system (CNS), participate into the inflammatory response in AD. Glia polarize into different phenotypes during neurodegeneration. Pro-inflammatory glia produce cytokines (IL-1β, TNF-α, and IL-6) resulting into debris aggregates and neurotoxicity. Anti-inflammatory phenotypes produce cytokines (IL-4 and IL-10) to release the inflammation. Electroacupuncture is a useful treatment that has been found to slow the neurodegeneration in animals through experimentation and in humans through clinical trials. The aim of this study was to uncover the mechanisms of glia activation, microglia polarization, and cytokine secretion regulated by electroacupuncture as a treatment for AD. Methods: Twenty male Sprague-Dawley (SD) rats were randomly divided into four groups: Control group (Control), Normal saline group (NS), AD group (AD), and Electroacupuncture group (Acupuncture). The AD and Acupuncture groups were bilaterally injected with Aβ1 - 42 into the CA1 field of the hippocampus. The Acupuncture group received electroacupuncture stimulation on the acupoint "Baihui" (GV20) for 6 days per week for a total of 3 weeks. The Morris Water Maze (MWM) was used to evaluate learning and memory capacity. Immunofluorescence was used to stain GFAP and Iba1 of the DG and CA1 in the hippocampus, which, respectively, expressed the activation of astrocyte and microglia. The M1 microglia marker, inducible nitric oxide synthase (iNOS), and M2 marker Arginase 1 (Arg1) were used to analyze the polarization of microglia. The pro-inflammatory cytokines (IL-1β, TNF-α, and IL-6), anti-inflammatory cytokines (IL-4 and IL-10), and pathway-molecules (p65 and Stat6) were tested to analyze the glia inflammatory response by immunofluorescence and polymerase chain reaction (PCR). Results: The MWM results showed that electroacupuncture improves the escape latency time and the swimming distance of AD rats. The number of GFAP and Iba1 cells significantly increased in AD rats, but electroacupuncture decreased the cells. The iNOS-positive cells were significantly increased in AD, and electroacupuncture decreased the positive cells. Electroacupuncture elevated Arg1-positive cells in AD rats. Electroacupuncture decreased the glia pro-inflammatory cytokine expression and increased the anti-inflammatory cytokine expression in AD rats. Furthermore, electroacupuncture inhibited the NF-κB pathway molecule (p65) while raising the Stat6 pathway molecule (Stat6). Conclusion: These results provide evidence that electroacupuncture improves the recognition abilities and memory of AD rats. Electroacupuncture inhibits the activation of glia and polarizes microglia toward the M2 phenotype. Electroacupuncture decreased the pro-inflammatory cytokines (IL-1β, TNF-α, and IL-6) and increased the anti-inflammatory cytokines (IL-4 and IL-10). Furthermore, electroacupuncture affects the immune responses through inhibition of NF-κB pathway but activation of Stat6 pathway.
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Affiliation(s)
- Lushuang Xie
- College of Basic Medicine, Chengdu University of Traditional Chinese Medicine, Chengdu, China.,Institute of Electroacupuncture and Homeostasis Regulation, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Yi Liu
- Department of Neurology, Dalian Municipal Central Hospital, Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Ning Zhang
- Electroacupuncture and Moxibustion College, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Chenyu Li
- Electroacupuncture and Moxibustion College, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Aaron F Sandhu
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States.,Department of Orthopedic Surgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States
| | - George Williams
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States.,Department of Orthopedic Surgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States
| | - Yan Shen
- Electroacupuncture and Moxibustion College, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Hongying Li
- Electroacupuncture and Moxibustion College, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Qiaofeng Wu
- Institute of Electroacupuncture and Homeostasis Regulation, Chengdu University of Traditional Chinese Medicine, Chengdu, China.,Electroacupuncture and Moxibustion College, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Shuguang Yu
- Institute of Electroacupuncture and Homeostasis Regulation, Chengdu University of Traditional Chinese Medicine, Chengdu, China.,Electroacupuncture and Moxibustion College, Chengdu University of Traditional Chinese Medicine, Chengdu, China
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18
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Tournier BB, Tsartsalis S, Ceyzériat K, Fraser BH, Grégoire MC, Kövari E, Millet P. Astrocytic TSPO Upregulation Appears Before Microglial TSPO in Alzheimer's Disease. J Alzheimers Dis 2021; 77:1043-1056. [PMID: 32804124 PMCID: PMC7683091 DOI: 10.3233/jad-200136] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Background: In vivo PET/SPECT imaging of neuroinflammation is primarily based on the estimation of the 18 kDa-translocator-protein (TSPO). However, TSPO is expressed by different cell types which complicates the interpretation. Objective: The present study evaluates the cellular origin of TSPO alterations in Alzheimer’s disease (AD). Methods: The TSPO cell origin was evaluated by combining radioactive imaging approaches using the TSPO radiotracer [125I]CLINDE and fluorescence-activated cell sorting, in a rat model of AD (TgF344-AD) and in AD subjects. Results: In the hippocampus of TgF344-AD rats, TSPO overexpression not only concerns glial cells but the increase is visible at 12 and 24 months in astrocytes and only at 24 months in microglia. In the temporal cortex of AD subjects, TSPO upregulation involved only glial cells. However, the mechanism of this upregulation appears different with an increase in the number of TSPO binding sites per cell without cell proliferation in the rat, and a microglial cell population expansion with a constant number of binding sites per cell in human AD. Conclusion: These data indicate an earlier astrocyte intervention than microglia and that TSPO in AD probably is an exclusive marker of glial activity without interference from other TSPO-expressing cells. This observation indicates that the interpretation of TSPO imaging depends on the stage of the pathology, and highlights the particular role of astrocytes.
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Affiliation(s)
- Benjamin B Tournier
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Switzerland
| | - Stergios Tsartsalis
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Switzerland
| | - Kelly Ceyzériat
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Switzerland.,Division of Nuclear medicine, University Hospitals of Geneva, Switzerland
| | - Ben H Fraser
- ANSTO LifeSciences, Australian Nuclear Science and Technology Organisation, New Illawarra Road, Sydney, NSW, Australia
| | - Marie-Claude Grégoire
- ANSTO LifeSciences, Australian Nuclear Science and Technology Organisation, New Illawarra Road, Sydney, NSW, Australia
| | - Enikö Kövari
- Division of Geriatric Psychiatry, Department of Mental Health and Psychiatry, University Hospitals of Geneva, Switzerland.,Department of Psychiatry, University of Geneva, Switzerland
| | - Philippe Millet
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Switzerland.,Department of Psychiatry, University of Geneva, Switzerland
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19
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Radhakrishnan H, Ubele MF, Krumholz SM, Boaz K, Mefford JL, Jones ED, Meacham B, Smiley J, Puskás LG, Powell DK, Norris CM, Stark CEL, Head E. Tacrolimus Protects against Age-Associated Microstructural Changes in the Beagle Brain. J Neurosci 2021; 41:5124-5133. [PMID: 33952632 PMCID: PMC8197636 DOI: 10.1523/jneurosci.0361-21.2021] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 04/09/2021] [Accepted: 04/16/2021] [Indexed: 11/21/2022] Open
Abstract
The overexpression of calcineurin leads to astrocyte hyperactivation, neuronal death, and inflammation, which are characteristics often associated with pathologic aging and Alzheimer's disease. In this study, we tested the hypothesis that tacrolimus, a calcineurin inhibitor, prevents age-associated microstructural atrophy, which we measured using higher-order diffusion MRI, in the middle-aged beagle brain (n = 30, male and female). We find that tacrolimus reduces hippocampal (p = 0.001) and parahippocampal (p = 0.002) neurite density index, as well as protects against an age-associated increase in the parahippocampal (p = 0.007) orientation dispersion index. Tacrolimus also protects against an age-related decrease in fractional anisotropy in the prefrontal cortex (p < 0.0001). We also show that these microstructural alterations precede cognitive decline and gross atrophy. These results support the idea that calcineurin inhibitors may have the potential to prevent aging-related pathology if administered at middle age.SIGNIFICANCE STATEMENT Hyperactive calcineurin signaling causes neuroinflammation and other neurobiological changes often associated with pathologic aging and Alzheimer's disease (AD). Controlling the expression of calcineurin before gross cognitive deficits are observable might serve as a promising avenue for preventing AD pathology. In this study, we show that the administration of the calcineurin inhibitor, tacrolimus, over 1 year prevents age- and AD-associated microstructural changes in the hippocampus, parahippocampal cortex, and prefrontal cortex of the middle-aged beagle brain, with no noticeable adverse effects. Tacrolimus is already approved by the Food and Drug Administration for use in humans to prevent solid organ transplant rejection, and our results bolster the promise of this drug to prevent AD and aging-related pathology.
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Affiliation(s)
- Hamsanandini Radhakrishnan
- Mathematical, Computational and Systems Biology, University of California, Irvine, Irvine, California 92697
| | - Margo F Ubele
- Sanders Brown Center on Aging, Department of Pharmacology and Nutritional Sciences, College of Medicine, University of Kentucky, Lexington, Kentucky 40506
| | - Stephanie M Krumholz
- Sanders Brown Center on Aging, Department of Pharmacology and Nutritional Sciences, College of Medicine, University of Kentucky, Lexington, Kentucky 40506
| | - Kathy Boaz
- Sanders Brown Center on Aging, Department of Pharmacology and Nutritional Sciences, College of Medicine, University of Kentucky, Lexington, Kentucky 40506
| | - Jennifer L Mefford
- Division of Laboratory Animal Resources, University of Kentucky, Lexington, Kentucky 40506
| | - Erin Denhart Jones
- Division of Laboratory Animal Resources, University of Kentucky, Lexington, Kentucky 40506
| | - Beverly Meacham
- Magnetic Resonance Imaging and Spectroscopy Center, University of Kentucky, Lexington, Kentucky 40506
| | - Jeffrey Smiley
- Division of Laboratory Animal Resources, University of Kentucky, Lexington, Kentucky 40506
| | | | - David K Powell
- Magnetic Resonance Imaging and Spectroscopy Center, University of Kentucky, Lexington, Kentucky 40506
| | - Christopher M Norris
- Sanders Brown Center on Aging, Department of Pharmacology and Nutritional Sciences, College of Medicine, University of Kentucky, Lexington, Kentucky 40506
| | - Craig E L Stark
- Mathematical, Computational and Systems Biology, University of California, Irvine, Irvine, California 92697
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, California 92697
| | - Elizabeth Head
- Department of Pathology & Laboratory Medicine, University of California, Irvine, Irvine, California 92697
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20
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Zhu FD, Hu YJ, Yu L, Zhou XG, Wu JM, Tang Y, Qin DL, Fan QZ, Wu AG. Nanoparticles: A Hope for the Treatment of Inflammation in CNS. Front Pharmacol 2021; 12:683935. [PMID: 34122112 PMCID: PMC8187807 DOI: 10.3389/fphar.2021.683935] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 04/26/2021] [Indexed: 12/12/2022] Open
Abstract
Neuroinflammation, an inflammatory response within the central nervous system (CNS), is a main hallmark of common neurodegenerative diseases, including Alzheimer’s disease (AD), Parkinson’s disease (PD), and amyotrophic lateral sclerosis (ALS), among others. The over-activated microglia release pro-inflammatory cytokines, which induces neuronal death and accelerates neurodegeneration. Therefore, inhibition of microglia over-activation and microglia-mediated neuroinflammation has been a promising strategy for the treatment of neurodegenerative diseases. Many drugs have shown promising therapeutic effects on microglia and inflammation. However, the blood–brain barrier (BBB)—a natural barrier preventing brain tissue from contact with harmful plasma components—seriously hinders drug delivery to the microglial cells in CNS. As an emerging useful therapeutic tool in CNS-related diseases, nanoparticles (NPs) have been widely applied in biomedical fields for use in diagnosis, biosensing and drug delivery. Recently, many NPs have been reported to be useful vehicles for anti-inflammatory drugs across the BBB to inhibit the over-activation of microglia and neuroinflammation. Therefore, NPs with good biodegradability and biocompatibility have the potential to be developed as an effective and minimally invasive carrier to help other drugs cross the BBB or as a therapeutic agent for the treatment of neuroinflammation-mediated neurodegenerative diseases. In this review, we summarized various nanoparticles applied in CNS, and their mechanisms and effects in the modulation of inflammation responses in neurodegenerative diseases, providing insights and suggestions for the use of NPs in the treatment of neuroinflammation-related neurodegenerative diseases.
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Affiliation(s)
- Feng-Dan Zhu
- Sichuan Key Medical Laboratory of New Drug Discovery and Drugability Evaluation, Luzhou Key Laboratory of Activity Screening and Druggability Evaluation for Chinese Materia Medica, Key Laboratory of Medical Electrophysiology of Ministry of Education, School of Pharmacy, Southwest Medical University, Luzhou, China
| | - Yu-Jiao Hu
- Sichuan Key Medical Laboratory of New Drug Discovery and Drugability Evaluation, Luzhou Key Laboratory of Activity Screening and Druggability Evaluation for Chinese Materia Medica, Key Laboratory of Medical Electrophysiology of Ministry of Education, School of Pharmacy, Southwest Medical University, Luzhou, China.,Department of Anesthesia, Southwest Medical University, Luzhou, China
| | - Lu Yu
- Sichuan Key Medical Laboratory of New Drug Discovery and Drugability Evaluation, Luzhou Key Laboratory of Activity Screening and Druggability Evaluation for Chinese Materia Medica, Key Laboratory of Medical Electrophysiology of Ministry of Education, School of Pharmacy, Southwest Medical University, Luzhou, China
| | - Xiao-Gang Zhou
- Sichuan Key Medical Laboratory of New Drug Discovery and Drugability Evaluation, Luzhou Key Laboratory of Activity Screening and Druggability Evaluation for Chinese Materia Medica, Key Laboratory of Medical Electrophysiology of Ministry of Education, School of Pharmacy, Southwest Medical University, Luzhou, China
| | - Jian-Ming Wu
- Sichuan Key Medical Laboratory of New Drug Discovery and Drugability Evaluation, Luzhou Key Laboratory of Activity Screening and Druggability Evaluation for Chinese Materia Medica, Key Laboratory of Medical Electrophysiology of Ministry of Education, School of Pharmacy, Southwest Medical University, Luzhou, China
| | - Yong Tang
- Sichuan Key Medical Laboratory of New Drug Discovery and Drugability Evaluation, Luzhou Key Laboratory of Activity Screening and Druggability Evaluation for Chinese Materia Medica, Key Laboratory of Medical Electrophysiology of Ministry of Education, School of Pharmacy, Southwest Medical University, Luzhou, China
| | - Da-Lian Qin
- Sichuan Key Medical Laboratory of New Drug Discovery and Drugability Evaluation, Luzhou Key Laboratory of Activity Screening and Druggability Evaluation for Chinese Materia Medica, Key Laboratory of Medical Electrophysiology of Ministry of Education, School of Pharmacy, Southwest Medical University, Luzhou, China
| | - Qing-Ze Fan
- Sichuan Key Medical Laboratory of New Drug Discovery and Drugability Evaluation, Luzhou Key Laboratory of Activity Screening and Druggability Evaluation for Chinese Materia Medica, Key Laboratory of Medical Electrophysiology of Ministry of Education, School of Pharmacy, Southwest Medical University, Luzhou, China.,Department of Pharmacy, Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - An-Guo Wu
- Sichuan Key Medical Laboratory of New Drug Discovery and Drugability Evaluation, Luzhou Key Laboratory of Activity Screening and Druggability Evaluation for Chinese Materia Medica, Key Laboratory of Medical Electrophysiology of Ministry of Education, School of Pharmacy, Southwest Medical University, Luzhou, China.,Department of Pharmacy, Affiliated Hospital of Southwest Medical University, Luzhou, China
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21
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Edler MK, Mhatre-Winters I, Richardson JR. Microglia in Aging and Alzheimer's Disease: A Comparative Species Review. Cells 2021; 10:1138. [PMID: 34066847 PMCID: PMC8150617 DOI: 10.3390/cells10051138] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 04/30/2021] [Accepted: 05/05/2021] [Indexed: 12/11/2022] Open
Abstract
Microglia are the primary immune cells of the central nervous system that help nourish and support neurons, clear debris, and respond to foreign stimuli. Greatly impacted by their environment, microglia go through rapid changes in cell shape, gene expression, and functional behavior during states of infection, trauma, and neurodegeneration. Aging also has a profound effect on microglia, leading to chronic inflammation and an increase in the brain's susceptibility to neurodegenerative processes that occur in Alzheimer's disease. Despite the scientific community's growing knowledge in the field of neuroinflammation, the overall success rate of drug treatment for age-related and neurodegenerative diseases remains incredibly low. Potential reasons for the lack of translation from animal models to the clinic include the use of a single species model, an assumption of similarity in humans, and ignoring contradictory data or information from other species. To aid in the selection of validated and predictive animal models and to bridge the translational gap, this review evaluates similarities and differences among species in microglial activation and density, morphology and phenotype, cytokine expression, phagocytosis, and production of oxidative species in aging and Alzheimer's disease.
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Affiliation(s)
- Melissa K. Edler
- Department of Anthropology, School of Biomedical Sciences, Brain Health Research Institute, Kent State University, Kent, OH 44240, USA;
| | - Isha Mhatre-Winters
- School of Biomedical Sciences, College of Arts and Sciences, Kent State University, Kent, OH 44240, USA;
- Robert Stempel College of Public Health and Social Work, Florida International University, Miami, FL 33199, USA
| | - Jason R. Richardson
- Robert Stempel College of Public Health and Social Work, Florida International University, Miami, FL 33199, USA
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22
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Gavriel Y, Rabinovich-Nikitin I, Ezra A, Barbiro B, Solomon B. Subcutaneous Administration of AMD3100 into Mice Models of Alzheimer's Disease Ameliorated Cognitive Impairment, Reduced Neuroinflammation, and Improved Pathophysiological Markers. J Alzheimers Dis 2021; 78:653-671. [PMID: 33016905 DOI: 10.3233/jad-200506] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND Alzheimer's disease (AD), the prevalent dementia in the elderly, involves many related and interdependent pathologies that manifest simultaneously, leading to cognitive impairment and death. Amyloid-β (Aβ) accumulation in the brain triggers the onset of AD, accompanied by neuroinflammatory response and pathological changes. The CXCR4/CXCL12 (SDF1) axis is one of the major signal transduction cascades involved in the inflammation process and regulation of homing of hematopoietic stem cells (HSCs) within the bone marrow niche. Inhibition of the axis with AMD3100, a reversible antagonist of CXCR4 mobilizes endogenous HSCs from the bone marrow into the periphery, facilitating the recruitment of bone marrow-derived microglia-like cells into the brain, attenuates the neuroinflammation process that involves release of excitotoxic markers such as TNFα, intracellular Ca2 +, and glutamate and upregulates monocarboxylate transporter 1, the major L-lactate transporter in the brain. OBJECTIVE Herein, we investigate if administration of a combination of AMD3100 and L-lactate may have beneficial effects in the treatment of AD. METHODS We tested the feasibility of the combined treatment for short- and long-term efficacy for inducing endogenous stem cells' mobilization and attenuation of neuroinflammation in two distinct amyloid-β-induced AD mouse models. RESULTS The combined treatment did not demonstrate any adverse effects on the mice, and resulted in a significant improvement in cognitive/memory functions, attenuated neuroinflammation, and alleviated AD pathologies compared to each treatment alone. CONCLUSION This study showed AMD3100's beneficial effect in ameliorating AD pathogenesis, suggesting an alternative to the multistep procedures of transplantation of stem cells in the treatment of AD.
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Affiliation(s)
- Yuval Gavriel
- The Shmunis School of Biomedicine and Cancer Research, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Inna Rabinovich-Nikitin
- The Shmunis School of Biomedicine and Cancer Research, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Assaf Ezra
- The Shmunis School of Biomedicine and Cancer Research, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Becki Barbiro
- The Shmunis School of Biomedicine and Cancer Research, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Beka Solomon
- The Shmunis School of Biomedicine and Cancer Research, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
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23
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Preclinical Marmoset Model for Targeting Chronic Inflammation as a Strategy to Prevent Alzheimer's Disease. Vaccines (Basel) 2021; 9:vaccines9040388. [PMID: 33920929 PMCID: PMC8071309 DOI: 10.3390/vaccines9040388] [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: 02/02/2021] [Revised: 04/08/2021] [Accepted: 04/13/2021] [Indexed: 11/17/2022] Open
Abstract
Due to the aging population, modern society is facing an increasing prevalence of neurological diseases such as Alzheimer’s disease (AD). AD is an age-related chronic neurodegenerative disorder for which no satisfying therapy exists. Understanding the mechanisms underlying the onset of AD is necessary to find targets for protective treatment. There is growing awareness of the essential role of the immune system in the early AD pathology. Amyloidopathy, the main feature of early-stage AD, has a deregulating effect on the immune function. This is reciprocal as the immune system also affects amyloidopathy. It seems that the inflammatory reaction shows a heterogeneous pattern depending on the stage of the disease and the variation between individuals, making not only the target but also the timing of treatment important. The lack of relevant translational animal models that faithfully reproduce clinical and pathogenic features of AD is a major cause of the delay in developing new disease-modifying therapies and their optimal timing of administration. This review describes the communication between amyloidopathy and inflammation and the possibility of using nonhuman primates as a relevant animal model for preclinical AD research.
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24
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Yu T, Quan H, Xu Y, Dou Y, Wang F, Lin Y, Qi X, Zhao Y, Liu X. A β-Induced Repressor Element 1-Silencing Transcription Factor (REST) Gene Delivery Suppresses Activation of Microglia-Like BV-2 Cells. Neural Plast 2020; 2020:8888871. [PMID: 33029126 PMCID: PMC7528025 DOI: 10.1155/2020/8888871] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Revised: 08/18/2020] [Accepted: 08/24/2020] [Indexed: 12/28/2022] Open
Abstract
Compelling evidence from basic molecular biology has demonstrated the crucial role of microglia in the pathogenesis of Alzheimer's disease (AD). Microglia were believed to play a dual role in both promoting and inhibiting Alzheimer's disease progression. It is of great significance to regulate the function of microglia and make them develop in a favorable way. In the present study, we investigated the function of repressor element 1-silencing transcription factor (REST) in Aβ 1-42-induced BV-2 cell dysfunction. We concluded that Aβ 1-42 could promote type I activation of BV-2 cells and induce cell proliferation, migration, and proinflammation cytokine TNF-α, IL-1β, and IL-6 expression. Meanwhile, REST was upregulated, and nuclear translocalization took place due to Aβ 1-42 stimulation. When REST was knocked down by a specific short hairpin RNA (sh-RNA), BV-2 cell proliferation, migration, and proinflammation cytokine expression and secretion induced by Aβ 1-42 were increased, demonstrating that REST may act as a repressor of microglia-like BV-2 cell activation.
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Affiliation(s)
- Tongya Yu
- Shanghai Tenth People's Hospital of Tongji University, Tongji University, Middle Yanchang Rd. 301#, Jingan District, Shanghai, China 200072
| | - Hui Quan
- Shanghai Tenth People's Hospital of Tongji University, Tongji University, Middle Yanchang Rd. 301#, Jingan District, Shanghai, China 200072
| | - Yuzhen Xu
- Shanghai Tenth People's Hospital of Tongji University, Tongji University, Middle Yanchang Rd. 301#, Jingan District, Shanghai, China 200072
| | - Yunxiao Dou
- Shanghai Tenth People's Hospital of Tongji University, Tongji University, Middle Yanchang Rd. 301#, Jingan District, Shanghai, China 200072
| | - Feihong Wang
- Shanghai Tenth People's Hospital of Tongji University, Nanjing Medical University, Middle Yanchang Rd. 301#, Jingan District, Shanghai, China 200072
| | - Yingying Lin
- Shanghai Tenth People's Hospital of Tongji University, Tongji University, Middle Yanchang Rd. 301#, Jingan District, Shanghai, China 200072
| | - Xue Qi
- Shanghai Tenth People's Hospital of Tongji University, Tongji University, Middle Yanchang Rd. 301#, Jingan District, Shanghai, China 200072
| | - Yanxin Zhao
- Shanghai Tenth People's Hospital of Tongji University, Tongji University, Middle Yanchang Rd. 301#, Jingan District, Shanghai, China 200072
| | - Xueyuan Liu
- Shanghai Tenth People's Hospital of Tongji University, Tongji University, Middle Yanchang Rd. 301#, Jingan District, Shanghai, China 200072
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25
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Belaya I, Ivanova M, Sorvari A, Ilicic M, Loppi S, Koivisto H, Varricchio A, Tikkanen H, Walker FR, Atalay M, Malm T, Grubman A, Tanila H, Kanninen KM. Astrocyte remodeling in the beneficial effects of long-term voluntary exercise in Alzheimer's disease. J Neuroinflammation 2020; 17:271. [PMID: 32933545 PMCID: PMC7493971 DOI: 10.1186/s12974-020-01935-w] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 08/19/2020] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Increased physical exercise improves cognitive function and reduces pathology associated with Alzheimer's disease (AD). However, the mechanisms underlying the beneficial effects of exercise in AD on the level of specific brain cell types remain poorly investigated. The involvement of astrocytes in AD pathology is widely described, but their exact role in exercise-mediated neuroprotection warrant further investigation. Here, we investigated the effect of long-term voluntary physical exercise on the modulation of the astrocyte state. METHODS Male 5xFAD mice and their wild-type littermates had free access to a running wheel from 1.5 to 7 months of age. A battery of behavioral tests was used to assess the effects of voluntary exercise on cognition and learning. Neuronal loss, impairment in neurogenesis, beta-amyloid (Aβ) deposition, and inflammation were evaluated using a variety of histological and biochemical measurements. Sophisticated morphological analyses were performed to delineate the specific involvement of astrocytes in exercise-induced neuroprotection in the 5xFAD mice. RESULTS Long-term voluntary physical exercise reversed cognitive impairment in 7-month-old 5xFAD mice without affecting neurogenesis, neuronal loss, Aβ plaque deposition, or microglia activation. Exercise increased glial fibrillary acid protein (GFAP) immunoreactivity and the number of GFAP-positive astrocytes in 5xFAD hippocampi. GFAP-positive astrocytes in hippocampi of the exercised 5xFAD mice displayed increases in the numbers of primary branches and in the soma area. In general, astrocytes distant from Aβ plaques were smaller in size and possessed simplified processes in comparison to plaque-associated GFAP-positive astrocytes. Morphological alterations of GFAP-positive astrocytes occurred concomitantly with increased astrocytic brain-derived neurotrophic factor (BDNF) and restoration of postsynaptic protein PSD-95. CONCLUSIONS Voluntary physical exercise modulates the reactive astrocyte state, which could be linked via astrocytic BDNF and PSD-95 to improved cognition in 5xFAD hippocampi. The molecular pathways involved in this modulation could potentially be targeted for benefit against AD.
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Affiliation(s)
- Irina Belaya
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, FI-70211, Kuopio, Finland
| | - Mariia Ivanova
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, FI-70211, Kuopio, Finland
| | - Annika Sorvari
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, FI-70211, Kuopio, Finland
| | - Marina Ilicic
- School of Biomedical Sciences and Pharmacy and the Priority Research Centre for Stroke and Brain Injury, The University of Newcastle, University Dr, Callaghan, NSW, 2308, Australia
| | - Sanna Loppi
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, FI-70211, Kuopio, Finland
| | - Hennariikka Koivisto
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, FI-70211, Kuopio, Finland
| | - Alessandra Varricchio
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, FI-70211, Kuopio, Finland
| | - Heikki Tikkanen
- Institute of Biomedicine, University of Eastern Finland, FI-70211, Kuopio, Finland
| | - Frederick R Walker
- School of Biomedical Sciences and Pharmacy and the Priority Research Centre for Stroke and Brain Injury, The University of Newcastle, University Dr, Callaghan, NSW, 2308, Australia
| | - Mustafa Atalay
- Institute of Biomedicine, University of Eastern Finland, FI-70211, Kuopio, Finland
| | - Tarja Malm
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, FI-70211, Kuopio, Finland
| | - Alexandra Grubman
- Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute, Melbourne, Australia
- Australian Regenerative Medicine Institute, Monash University, Melbourne, Australia
| | - Heikki Tanila
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, FI-70211, Kuopio, Finland
| | - Katja M Kanninen
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, FI-70211, Kuopio, Finland.
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26
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Bechter K. The Challenge of Assessing Mild Neuroinflammation in Severe Mental Disorders. Front Psychiatry 2020; 11:773. [PMID: 32973573 PMCID: PMC7469926 DOI: 10.3389/fpsyt.2020.00773] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Accepted: 07/21/2020] [Indexed: 12/13/2022] Open
Abstract
Recent psychoneuroimmunology research has provided new insight into the etiology and pathogenesis of severe mental disorders (SMDs). The mild encephalitis (ME) hypothesis was developed with the example of human Borna disease virus infection years ago and proposed, that a subgroup SMD patients, mainly from the broad schizophrenic and affective spectrum, could suffer from mild neuroinflammation, which remained undetected because hard to diagnose with available diagnostic methods. Recently, in neurology an emerging new subgroup of autoimmune encephalitis (AE) cases suffering from various neurological syndromes was described in context with the discovery of an emerging list of Central Nervous System (CNS) autoantibodies. Similarly in psychiatry, consensus criteria of autoimmune psychosis (AP) were developed for patients presenting with CNS autoantibodies together with isolated psychiatric symptoms and paraclinical findings of (mild) neuroinflammation, which in fact match also the previously proposed ME criteria. Nevertheless, identifying mild neuroinflammation in vivo in the individual SMD case remains still a major clinical challenge and the possibility that further cases of ME remain still under diagnosed appears an plausible possibility. In this paper a critical review of recent developments and remaining challenges in the research and clinical diagnosis of mild neuroinflammation in SMDs and in general and in transdisciplinary perspective to psycho-neuro-immunology and neuropsychiatry is given. Present nosological classifications of neuroinflammatory disorders are reconsidered with regard to findings from experimental and clinical research. A refined grading list of clinical states including "classical" encephalitis, AE, AP/ME,and newly proposed terms like parainflammation, stress-induced parainflammation and neuroprogression, and their respective relation to neurodegeneration is presented, which may be useful for further research on the possible causative role of mild neuroinflammation in SMDs. Beyond, an etiology-focused subclassification of ME subtypes, like autoimmune ME or infectious ME, appears to be required for differential diagnosis and individualized treatment. The present status of the clinical diagnosis of mild neuroinflammatory mechanisms involved in SMDs is outlined with the example of actual diagnosis and therapy in AP. Ideas for future research to unravel the contribution of mild neuroinflammation in the causality of SMDs and the difficulties expected to come to novel immune modulatory, anti-infectious or anti-inflammatory therapeutic principles in the sense of precision medicine are discussed.
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Affiliation(s)
- Karl Bechter
- Department for Psychiatry and Psychotherapy II, Ulm University, Bezirkskrankenhaus Günzburg, Günzburg, Germany
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27
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Tournier BB, Tsartsalis S, Ceyzériat K, Medina Z, Fraser BH, Grégoire MC, Kövari E, Millet P. Fluorescence-activated cell sorting to reveal the cell origin of radioligand binding. J Cereb Blood Flow Metab 2020; 40:1242-1255. [PMID: 31242048 PMCID: PMC7238369 DOI: 10.1177/0271678x19860408] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Many studies have explored the role of TSPO (18 kDa translocator protein) as a marker of neuroinflammation using single-photon emission computed tomography (SPECT) or positron emission tomography (PET). In vivo imaging does not allow to determine the cells in which TSPO is altered. We propose a methodology based on fluorescence-activated cell sorting to sort different cell types of radioligand-treated tissues. We compared left/right hippocampus of rats in response to a unilateral injection of lipopolysaccharide (LPS), ciliary neurotrophic factor (CNTF) or saline. We finally applied this methodology in human samples (Alzheimer's disease patients and controls). Our data show that the pattern of TSPO overexpression differs across animal models of acute neuroinflammation. LPS induces a microglial expansion and an increase in microglial TSPO binding. CNTF is associated with an increase in TSPO binding in microglia and astrocytes in association with an increase in the number of microglial binding sites per cell. In humans, we show that the increase in CLINDE binding in Alzheimer's disease concerns microglia and astrocytes in the presence of a microglial expansion. Thus, the cellular basis of TSPO overexpression is condition dependent, and alterations in TSPO binding found in PET/SPECT imaging studies cannot be attributed to particular cell types indiscriminately.
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Affiliation(s)
- Benjamin B Tournier
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Geneva, Switzerland
| | - Stergios Tsartsalis
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Geneva, Switzerland
| | - Kelly Ceyzériat
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Geneva, Switzerland.,Division of Nuclear medicine, University Hospitals of Geneva, Geneva, Switzerland
| | - Zadith Medina
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Geneva, Switzerland
| | - Ben H Fraser
- ANSTO LifeSciences, Australian Nuclear Science and Technology Organisation, Sydney, NSW, Australia
| | - Marie-Claude Grégoire
- ANSTO LifeSciences, Australian Nuclear Science and Technology Organisation, Sydney, NSW, Australia
| | - Enikö Kövari
- Division of Geriatric Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Geneva, Switzerland.,Department of Psychiatry, University of Geneva, Geneva, Switzerland
| | - Philippe Millet
- Division of Adult Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Geneva, Switzerland.,Department of Psychiatry, University of Geneva, Geneva, Switzerland
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28
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Rivera-Escalera F, Pinney JJ, Owlett L, Ahmed H, Thakar J, Olschowka JA, Elliott MR, O’Banion MK. IL-1β-driven amyloid plaque clearance is associated with an expansion of transcriptionally reprogrammed microglia. J Neuroinflammation 2019; 16:261. [PMID: 31822279 PMCID: PMC6902486 DOI: 10.1186/s12974-019-1645-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Accepted: 11/18/2019] [Indexed: 01/02/2023] Open
Abstract
BACKGROUND Neuroinflammation is thought to contribute to the pathogenesis of Alzheimer's disease (AD), yet numerous studies have demonstrated a beneficial role for neuroinflammation in amyloid plaque clearance. We have previously shown that sustained expression of IL-1β in the hippocampus of APP/PS1 mice decreases amyloid plaque burden independent of recruited CCR2+ myeloid cells, suggesting resident microglia as the main phagocytic effectors of IL-1β-induced plaque clearance. To date, however, the mechanisms of IL-1β-induced plaque clearance remain poorly understood. METHODS To determine whether microglia are involved in IL-1β-induced plaque clearance, APP/PS1 mice induced to express mature human IL-1β in the hippocampus via adenoviral transduction were treated with the Aβ fluorescent probe methoxy-X04 (MX04) and microglial internalization of fibrillar Aβ (fAβ) was analyzed by flow cytometry and immunohistochemistry. To assess microglial proliferation, APP/PS1 mice transduced with IL-1β or control were injected intraperitoneally with BrdU and hippocampal tissue was analyzed by flow cytometry. RNAseq analysis was conducted on microglia FACS sorted from the hippocampus of control or IL-1β-treated APP/PS1 mice. These microglia were also sorted based on MX04 labeling (MX04+ and MX04- microglia). RESULTS Resident microglia (CD45loCD11b+) constituted > 70% of the MX04+ cells in both Phe- and IL-1β-treated conditions, and < 15% of MX04+ cells were recruited myeloid cells (CD45hiCD11b+). However, IL-1β treatment did not augment the percentage of MX04+ microglia nor the quantity of fAβ internalized by individual microglia. Instead, IL-1β increased the total number of MX04+ microglia in the hippocampus due to IL-1β-induced proliferation. In addition, transcriptomic analyses revealed that IL-1β treatment was associated with large-scale changes in the expression of genes related to immune responses, proliferation, and cytokine signaling. CONCLUSIONS These studies show that IL-1β overexpression early in amyloid pathogenesis induces a change in the microglial gene expression profile and an expansion of microglial cells that facilitates Aβ plaque clearance.
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Affiliation(s)
- Fátima Rivera-Escalera
- Department of Neuroscience, University of Rochester School of Medicine and Dentistry, 601 Elmwood Avenue, Box 603, Rochester, NY 14642 USA
- David H. Smith Center for Vaccine Biology and Immunology, University of Rochester School of Medicine and Dentistry, Rochester, NY USA
| | - Jonathan J. Pinney
- David H. Smith Center for Vaccine Biology and Immunology, University of Rochester School of Medicine and Dentistry, Rochester, NY USA
- Department of Microbiology and Immunology, University of Rochester School of Medicine and Dentistry, Rochester, NY USA
| | - Laura Owlett
- Department of Neuroscience, University of Rochester School of Medicine and Dentistry, 601 Elmwood Avenue, Box 603, Rochester, NY 14642 USA
- Del Monte Neuroscience Institute, University of Rochester School of Medicine and Dentistry, Rochester, NY USA
| | - Hoda Ahmed
- Department of Neuroscience, University of Rochester School of Medicine and Dentistry, 601 Elmwood Avenue, Box 603, Rochester, NY 14642 USA
| | - Juilee Thakar
- Department of Microbiology and Immunology, University of Rochester School of Medicine and Dentistry, Rochester, NY USA
| | - John A. Olschowka
- Department of Neuroscience, University of Rochester School of Medicine and Dentistry, 601 Elmwood Avenue, Box 603, Rochester, NY 14642 USA
- Del Monte Neuroscience Institute, University of Rochester School of Medicine and Dentistry, Rochester, NY USA
| | - Michael R. Elliott
- David H. Smith Center for Vaccine Biology and Immunology, University of Rochester School of Medicine and Dentistry, Rochester, NY USA
- Department of Microbiology and Immunology, University of Rochester School of Medicine and Dentistry, Rochester, NY USA
| | - M. Kerry O’Banion
- Department of Neuroscience, University of Rochester School of Medicine and Dentistry, 601 Elmwood Avenue, Box 603, Rochester, NY 14642 USA
- Del Monte Neuroscience Institute, University of Rochester School of Medicine and Dentistry, Rochester, NY USA
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29
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Microglial activation, but not tau pathology, is independently associated with amyloid positivity and memory impairment. Neurobiol Aging 2019; 85:11-21. [PMID: 31698286 DOI: 10.1016/j.neurobiolaging.2019.09.019] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 08/22/2019] [Accepted: 09/25/2019] [Indexed: 12/13/2022]
Abstract
We sought to determine if upstream amyloid accumulation and downstream cognitive impairment have independent relationships with microglial activation and tau pathology. Fifty-eight older adults were stratified by amyloid and cognitive status based on 18F-florbetaben PET, history, and neuropsychological testing. Of these, 57 had 11C-PBR28 PET to measure microglial activation and 43 had 18F-MK-6240 PET to measure tau pathology. Amyloid and cognitive status were associated with increased overall binding for both 11C-PBR28 and 18F-MK-6240 (p's < 0.01). While there was no interaction between amyloid and cognitive status in their association with 11C-PBR28 binding (p = 0.6722), there was an interaction in their association with 18F-MK-6240 binding (p = 0.0115). Binding of both radioligands was greater in amyloid-positive controls than in amyloid-negative controls; however, this difference was seen in neocortical regions for 11C-PBR28 and only in medial temporal cortex for 18F-MK-6240. We conclude that, in the absence of cognitive symptoms, amyloid deposition has a greater association with microglial activation than with tau pathology.
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30
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Prospects and challenges of imaging neuroinflammation beyond TSPO in Alzheimer's disease. Eur J Nucl Med Mol Imaging 2019; 46:2831-2847. [PMID: 31396666 PMCID: PMC6879435 DOI: 10.1007/s00259-019-04462-w] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Accepted: 07/24/2019] [Indexed: 02/06/2023]
Abstract
Neuroinflammation, as defined by the activation of microglia and astrocytes, has emerged in the last years as a key element of the pathogenesis of neurodegenerative diseases based on genetic findings and preclinical and human studies. This has raised the need for new methodologies to assess and follow glial activation in patients, prompting the development of PET ligands for molecular imaging of glial cells and novel structural MRI and DTI tools leading to a multimodal approach. The present review describes the recent advancements in microglia and astrocyte biology in the context of health, ageing, and Alzheimer's disease, the most common dementia worldwide. The review further delves in molecular imaging discussing the challenges associated with past and present targets, including conflicting findings, and finally, presenting novel methodologies currently explored to improve our in vivo knowledge of the neuroinflammatory patterns in Alzheimer's disease. With glial cell activation as a potential therapeutic target in neurodegenerative diseases, the translational research between cell biologists, chemists, physicists, radiologists, and neurologists should be strengthened.
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31
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Ghosh A, Torraville SE, Mukherjee B, Walling SG, Martin GM, Harley CW, Yuan Q. An experimental model of Braak's pretangle proposal for the origin of Alzheimer's disease: the role of locus coeruleus in early symptom development. ALZHEIMERS RESEARCH & THERAPY 2019; 11:59. [PMID: 31266535 PMCID: PMC6607586 DOI: 10.1186/s13195-019-0511-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 06/06/2019] [Indexed: 12/22/2022]
Abstract
Background The earliest brain pathology related to Alzheimer’s disease (AD) is hyperphosphorylated soluble tau in the noradrenergic locus coeruleus (LC) neurons. Braak characterizes five pretangle tau stages preceding AD tangles. Pretangles begin in young humans and persist in the LC while spreading from there to other neuromodulatory neurons and, later, to the cortex. While LC pretangles appear in all by age 40, they do not necessarily result in AD prior to death. However, with age and pretangle spread, more individuals progress to AD stages. LC neurons are lost late, at Braak stages III–IV, when memory deficits appear. It is not clear if LC hyperphosphorylated tau generates the pathology and cognitive changes associated with preclinical AD. We use a rat model expressing pseudohyperphosphorylated human tau in LC to investigate the hypothesis that LC pretangles generate preclinical Alzheimer pathology. Methods We infused an adeno-associated viral vector carrying a human tau gene pseudophosphorylated at 14 sites common in LC pretangles into 2–3- or 14–16-month TH-Cre rats. We used odor discrimination to probe LC dysfunction, and we evaluated LC cell and fiber loss. Results Abnormal human tau was expressed in LC and exhibited somatodendritic mislocalization. In rats infused at 2–3 months old, 4 months post-infusion abnormal LC tau had transferred to the serotonergic raphe neurons. After 7 months, difficult similar odor discrimination learning was impaired. Impairment was associated with reduced LC axonal density in the olfactory cortex and upregulated β1-adrenoceptors. LC infusions in 14–16-month-old rats resulted in more severe outcomes. By 5–6 months post-infusion, rats were impaired even in simple odor discrimination learning. LC neuron number was reduced. Human tau appeared in the microglia and cortical neurons. Conclusions Our animal model suggests, for the first time, that Braak’s hypothesis that human AD originates with pretangle stages is plausible. LC pretangle progression here generates both preclinical AD pathological changes and cognitive decline. The odor discrimination deficits are similar to human odor identification deficits seen with aging and preclinical AD. When initiated in aged rats, pretangle stages progress rapidly and cause LC cell loss. These age-related outcomes are associated with a severe learning impairment consistent with memory decline in Braak stages III–IV. Electronic supplementary material The online version of this article (10.1186/s13195-019-0511-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Abhinaba Ghosh
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University of Newfoundland, St. John's, NL, A1B 3V6, Canada
| | - Sarah E Torraville
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University of Newfoundland, St. John's, NL, A1B 3V6, Canada.,Department of Psychology, Faculty of Science, Memorial University of Newfoundland, St. John's, NL, A1B 3X9, Canada
| | - Bandhan Mukherjee
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University of Newfoundland, St. John's, NL, A1B 3V6, Canada
| | - Susan G Walling
- Department of Psychology, Faculty of Science, Memorial University of Newfoundland, St. John's, NL, A1B 3X9, Canada
| | - Gerard M Martin
- Department of Psychology, Faculty of Science, Memorial University of Newfoundland, St. John's, NL, A1B 3X9, Canada
| | - Carolyn W Harley
- Department of Psychology, Faculty of Science, Memorial University of Newfoundland, St. John's, NL, A1B 3X9, Canada.
| | - Qi Yuan
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University of Newfoundland, St. John's, NL, A1B 3V6, Canada.
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Microbiota Alterations in Alzheimer’s Disease: Involvement of the Kynurenine Pathway and Inflammation. Neurotox Res 2019; 36:424-436. [DOI: 10.1007/s12640-019-00057-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Revised: 04/30/2019] [Accepted: 05/02/2019] [Indexed: 12/15/2022]
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The Evolving Dialogue of Microglia and Neurons in Alzheimer’s Disease: Microglia as Necessary Transducers of Pathology. Neuroscience 2019; 405:24-34. [DOI: 10.1016/j.neuroscience.2018.01.059] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2017] [Revised: 01/25/2018] [Accepted: 01/29/2018] [Indexed: 01/21/2023]
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Edler MK, Sherwood CC, Meindl RS, Munger E, Hopkins WD, Ely JJ, Erwin JM, Perl DP, Mufson EJ, Hof PR, Raghanti MA. Microglia changes associated to Alzheimer's disease pathology in aged chimpanzees. J Comp Neurol 2018; 526:2921-2936. [PMID: 30069930 PMCID: PMC6283685 DOI: 10.1002/cne.24484] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 05/11/2018] [Accepted: 05/16/2018] [Indexed: 01/01/2023]
Abstract
In Alzheimer's disease (AD), the brain's primary immune cells, microglia, become activated and are found in close apposition to amyloid beta (Aβ) protein plaques and neurofibrillary tangles (NFT). The present study evaluated microglia density and morphology in a large group of aged chimpanzees (n = 20, ages 37-62 years) with varying degrees of AD-like pathology. Using immunohistochemical and stereological techniques, we quantified the density of activated microglia and morphological variants (ramified, intermediate, and amoeboid) in postmortem chimpanzee brain samples from prefrontal cortex, middle temporal gyrus, and hippocampus, areas that show a high degree of AD pathology in humans. Microglia measurements were compared to pathological markers of AD in these cases. Activated microglia were consistently present across brain areas. In the hippocampus, CA3 displayed a higher density than CA1. Aβ42 plaque volume was positively correlated with higher microglial activation and with an intermediate morphology in the hippocampus. Aβ42-positive vessel volume was associated with increased hippocampal microglial activation. Activated microglia density and morphology were not associated with age, sex, pretangle density, NFT density, or tau neuritic cluster density. Aged chimpanzees displayed comparable patterns of activated microglia phenotypes as well as an association of increased microglial activation and morphological changes with Aβ deposition similar to AD patients. In contrast to human AD brains, activated microglia density was not significantly correlated with tau lesions. This evidence suggests that the chimpanzee brain may be relatively preserved during normal aging processes but not entirely protected from neurodegeneration as previously assumed.
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Affiliation(s)
- Melissa K. Edler
- School of Biomedical Sciences, Kent State University, Kent, OH 44242
- Department of Pharmaceutical Sciences, Northeast Ohio Medical University, Rootstown, OH 44272
| | - Chet C. Sherwood
- Department of Anthropology and Center for the Advanced Study of Human Paleobiology, The George Washington University, Washington, DC 20052
| | | | - Emily Munger
- School of Biomedical Sciences, Kent State University, Kent, OH 44242
| | - William D. Hopkins
- Division of Developmental and Cognitive Neuroscience, Yerkes National Primate Research Center, Atlanta, GA 30322
- Neuroscience Institute, Georgia State University, Atlanta, GA 30302
| | | | - Joseph M. Erwin
- Department of Anthropology and Center for the Advanced Study of Human Paleobiology, The George Washington University, Washington, DC 20052
| | - Daniel P. Perl
- Department of Pathology, Uniformed Services University of the Health Sciences, Bethesda, MD 20814
| | - Elliott J. Mufson
- Departments of Neurobiology and Neurology, Barrow Neurological Institute, Phoenix, AZ 85013
| | - Patrick R. Hof
- Fishberg Department of Neuroscience, Ronald M. Loeb Center for Alzheimer’s Disease, and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029
- New York Consortium for Evolutionary Primatology, New York, NY 10468
| | - Mary Ann Raghanti
- School of Biomedical Sciences, Kent State University, Kent, OH 44242
- Department of Anthropology, Kent State University, Kent, OH 44242
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Dard RF, Dahan L, Rampon C. Targeting hippocampal adult neurogenesis using transcription factors to reduce Alzheimer's disease-associated memory impairments. Hippocampus 2018; 29:579-586. [DOI: 10.1002/hipo.23052] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 09/10/2018] [Accepted: 10/05/2018] [Indexed: 12/23/2022]
Affiliation(s)
- Robin F. Dard
- Centre de Recherches sur la Cognition Animale (CRCA), Centre de Biologie Intégrative (CBI); Université de Toulouse, UPS; CNRS; Toulouse France
- Master BioSciences; ENS de Lyon, Université de Lyon; France
| | - Lionel Dahan
- Centre de Recherches sur la Cognition Animale (CRCA), Centre de Biologie Intégrative (CBI); Université de Toulouse, UPS; CNRS; Toulouse France
| | - Claire Rampon
- Centre de Recherches sur la Cognition Animale (CRCA), Centre de Biologie Intégrative (CBI); Université de Toulouse, UPS; CNRS; Toulouse France
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Streit WJ, Braak H, Del Tredici K, Leyh J, Lier J, Khoshbouei H, Eisenlöffel C, Müller W, Bechmann I. Microglial activation occurs late during preclinical Alzheimer's disease. Glia 2018; 66:2550-2562. [PMID: 30417428 DOI: 10.1002/glia.23510] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 07/18/2018] [Accepted: 07/18/2018] [Indexed: 01/10/2023]
Abstract
Sporadic Alzheimer's disease (AD) is marked by a lengthy preclinical phase during which patients are nonsymptomatic but show pathology in variable manifestations. Whether or not neuroinflammation occurs in such nondemented individuals is unknown. We evaluated the medial temporal lobe of 66 nondemented subjects, aged 42-93, in terms of tau pathology, Aβ deposition, and microglial activation. We show that 100% of subjects had neurofibrillary degeneration (NFD), 35% had Aβ deposits, and 8% revealed microglial activation in individuals where early amyloid formation was apparent by Congo Red staining. Amyloid-induced neuroinflammatory clusters of Iba1, CD68, and ferritin-positive microglia were evident in the immediate vicinity of aggregated Aβ. Microglia in the adjacent neuropil were nonactivated. Thus, neuroinflammation in AD represents a highly localized phagocyte reaction, essentially a foreign body response, geared toward removal of insoluble Aβ. Because clustered microglia in some amyloid plaques were dystrophic and ferritin-positive, we hypothesize that these cells were exhausted by their attempts to remove the aggregated, insoluble Aβ. Our findings show that the sequence of pathologic events in AD begins with tau pathology, followed by Aβ deposition, and then by microglial activation. Because only 8% of our subjects revealed all three hallmark pathologic features, we propose that these nondemented individuals were near the threshold of transitioning from nonsymptomatic to symptomatic disease. The onset of neuroinflammation in AD may thus represent a tipping point in AD pathogenesis. Our study suggests that the role of microglia in AD pathogenesis entails primarily the attempted removal of potentially toxic, extracellular material.
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Affiliation(s)
- Wolfgang J Streit
- Department of Neuroscience, University of Florida College of Medicine, Gainesville, Florida
| | - Heiko Braak
- Clinical Neuroanatomy (Department of Neurology), Center for Biomedical Research, University of Ulm, Ulm, Germany
| | - Kelly Del Tredici
- Clinical Neuroanatomy (Department of Neurology), Center for Biomedical Research, University of Ulm, Ulm, Germany
| | - Judith Leyh
- Institute of Anatomy, Leipzig University, Leipzig, Germany
| | - Julia Lier
- Institute of Anatomy, Leipzig University, Leipzig, Germany
| | - Habibeh Khoshbouei
- Department of Neuroscience, University of Florida College of Medicine, Gainesville, Florida
| | | | - Wolf Müller
- Department of Neuropathology, Leipzig University, Leipzig, Germany
| | - Ingo Bechmann
- Institute of Anatomy, Leipzig University, Leipzig, Germany
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Nirzhor SSR, Khan RI, Neelotpol S. The Biology of Glial Cells and Their Complex Roles in Alzheimer's Disease: New Opportunities in Therapy. Biomolecules 2018; 8:biom8030093. [PMID: 30201881 PMCID: PMC6164719 DOI: 10.3390/biom8030093] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 08/28/2018] [Accepted: 09/06/2018] [Indexed: 01/01/2023] Open
Abstract
Even though Alzheimer's disease (AD) is of significant interest to the scientific community, its pathogenesis is very complicated and not well-understood. A great deal of progress has been made in AD research recently and with the advent of these new insights more therapeutic benefits may be identified that could help patients around the world. Much of the research in AD thus far has been very neuron-oriented; however, recent studies suggest that glial cells, i.e., microglia, astrocytes, oligodendrocytes, and oligodendrocyte progenitor cells (NG2 glia), are linked to the pathogenesis of AD and may offer several potential therapeutic targets against AD. In addition to a number of other functions, glial cells are responsible for maintaining homeostasis (i.e., concentration of ions, neurotransmitters, etc.) within the central nervous system (CNS) and are crucial to the structural integrity of neurons. This review explores the: (i) role of glial cells in AD pathogenesis; (ii) complex functionalities of the components involved; and (iii) potential therapeutic targets that could eventually lead to a better quality of life for AD patients.
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Perez-Nievas BG, Serrano-Pozo A. Deciphering the Astrocyte Reaction in Alzheimer's Disease. Front Aging Neurosci 2018; 10:114. [PMID: 29922147 PMCID: PMC5996928 DOI: 10.3389/fnagi.2018.00114] [Citation(s) in RCA: 174] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2018] [Accepted: 04/03/2018] [Indexed: 12/24/2022] Open
Abstract
Reactive astrocytes were identified as a component of senile amyloid plaques in the cortex of Alzheimer's disease (AD) patients several decades ago. However, their role in AD pathophysiology has remained elusive ever since, in part owing to the extrapolation of the literature from primary astrocyte cultures and acute brain injury models to a chronic neurodegenerative scenario. Recent accumulating evidence supports the idea that reactive astrocytes in AD acquire neurotoxic properties, likely due to both a gain of toxic function and a loss of their neurotrophic effects. However, the diversity and complexity of this glial cell is only beginning to be unveiled, anticipating that astrocyte reaction might be heterogeneous as well. Herein we review the evidence from mouse models of AD and human neuropathological studies and attempt to decipher the main conundrums that astrocytes pose to our understanding of AD development and progression. We discuss the morphological features that characterize astrocyte reaction in the AD brain, the consequences of astrocyte reaction for both astrocyte biology and AD pathological hallmarks, and the molecular pathways that have been implicated in this reaction.
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Affiliation(s)
| | - Alberto Serrano-Pozo
- Alzheimer's Research Unit, MassGeneral Institute for Neurodegenerative Diseases (MIND), Department of Neurology, Massachusetts General Hospital, Boston, MA, United States
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Hopperton KE, Mohammad D, Trépanier MO, Giuliano V, Bazinet RP. Markers of microglia in post-mortem brain samples from patients with Alzheimer's disease: a systematic review. Mol Psychiatry 2018; 23:177-198. [PMID: 29230021 PMCID: PMC5794890 DOI: 10.1038/mp.2017.246] [Citation(s) in RCA: 297] [Impact Index Per Article: 49.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Revised: 08/15/2017] [Accepted: 09/14/2017] [Indexed: 02/07/2023]
Abstract
Neuroinflammation is proposed as one of the mechanisms by which Alzheimer's disease pathology, including amyloid-β plaques, leads to neuronal death and dysfunction. Increases in the expression of markers of microglia, the main neuroinmmune cell, are widely reported in brains from patients with Alzheimer's disease, but the literature has not yet been systematically reviewed to determine whether this is a consistent pathological feature. A systematic search was conducted in Medline, Embase and PsychINFO for articles published up to 23 February 2017. Papers were included if they quantitatively compared microglia markers in post-mortem brain samples from patients with Alzheimer's disease and aged controls without neurological disease. A total of 113 relevant articles were identified. Consistent increases in markers related to activation, such as major histocompatibility complex II (36/43 studies) and cluster of differentiation 68 (17/21 studies), were identified relative to nonneurological aged controls, whereas other common markers that stain both resting and activated microglia, such as ionized calcium-binding adaptor molecule 1 (10/20 studies) and cluster of differentiation 11b (2/5 studies), were not consistently elevated. Studies of ionized calcium-binding adaptor molecule 1 that used cell counts almost uniformly identified no difference relative to control, indicating that increases in activation occurred without an expansion of the total number of microglia. White matter and cerebellum appeared to be more resistant to these increases than other brain regions. Nine studies were identified that included high pathology controls, patients who remained free of dementia despite Alzheimer's disease pathology. The majority (5/9) of these studies reported higher levels of microglial markers in Alzheimer's disease relative to controls, suggesting that these increases are not solely a consequence of Alzheimer's disease pathology. These results show that increased markers of microglia are a consistent feature of Alzheimer's disease, though this seems to be driven primarily by increases in activation-associated markers, as opposed to markers of all microglia.
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Affiliation(s)
- K E Hopperton
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - D Mohammad
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, ON, Canada,Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada
| | - M O Trépanier
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - V Giuliano
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - R P Bazinet
- Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, ON, Canada,Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, FitzGerald Building, 150 College Street, Room 306, Toronto, ON M5S 3E2, Canada. E-mail:
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40
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Hoeijmakers L, Meerhoff GF, de Vries JW, Ruigrok SR, van Dam AM, van Leuven F, Korosi A, Lucassen PJ. The age-related slow increase in amyloid pathology in APP.V717I mice activates microglia, but does not alter hippocampal neurogenesis. Neurobiol Aging 2018; 61:112-123. [DOI: 10.1016/j.neurobiolaging.2017.09.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Revised: 09/12/2017] [Accepted: 09/14/2017] [Indexed: 01/09/2023]
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Pepe G, De Maglie M, Minoli L, Villa A, Maggi A, Vegeto E. Selective proliferative response of microglia to alternative polarization signals. J Neuroinflammation 2017; 14:236. [PMID: 29202771 PMCID: PMC5715534 DOI: 10.1186/s12974-017-1011-6] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Accepted: 11/22/2017] [Indexed: 01/29/2023] Open
Abstract
Background Microglia are resident myeloid cells of the central nervous system (CNS) that are maintained by self-renewal and actively participate in tissue homeostasis and immune defense. Under the influence of endogenous or pathological signals, microglia undertake biochemical transformations that are schematically classified as the pro-inflammatory M1 phenotype and the alternatively activated M2 state. Dysregulated proliferation of M1-activated microglia has detrimental effects, while an increased number of microglia with the alternative, pro-resolving phenotype might be beneficial in brain pathologies; however, the proliferative response of microglia to M2 signals is not yet known. We thus evaluated the ability of interleukin-4 (IL-4), a typical M2 and proliferative signal for peripheral macrophages, to induce microglia proliferation and compared it with other proliferative and M2 polarizing stimuli for macrophages, namely colony-stimulating factor-1 (CSF-1) and the estrogen hormone, 17β-estradiol (E2). Methods Recombinant IL-4 was delivered to the brain of adult mice by intracerebroventricular (i.c.v.) injection; whole brain areas or ex vivo-sorted microglia were analyzed by real-time PCR for assessing the mRNA levels of genes related with cell proliferation (Ki67, CDK-1, and CcnB2) and M2 polarization (Arg1, Fizz1, Ym-1) or by FACS analyses of in vivo BrdU incorporation in microglia. Primary cultures of microglia and astrocytes were also tested for proliferative effects. Results Our results show that IL-4 only slightly modified the expression of cell cycle-related genes in some brain areas but not in microglia, where it strongly enhanced M2 gene expression; on the contrary, brain delivery of CSF-1 triggered proliferation as well as M2 polarization of microglia both in vivo and in vitro. Similar to IL-4, the systemic E2 administration failed to induce microglia proliferation while it increased M2 gene expression. Conclusions Our data show that, in contrast to the wider responsiveness of peripheral macrophages, microglia proliferation is stimulated by selected M2 polarizing stimuli suggesting a role for the local microenvironment and developmental origin of tissue macrophages in regulating self-renewal following alternative activating stimuli. Electronic supplementary material The online version of this article (10.1186/s12974-017-1011-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Giovanna Pepe
- Center of Excellence on Neurodegenerative Diseases and Department Pharmacological and Biomolecular Sciences, University of Milan, Via Balzaretti, 9, 20133, Milan, Italy
| | - Marcella De Maglie
- Mouse and Animal Pathology Laboratory (MAPLab), Fondazione Filarete, Viale Ortles, 22/4, 20139, Milan, Italy.,Department of Veterinary Medicine, University of Milan, Via Celoria, 10, 20133, Milan, Italy
| | - Lucia Minoli
- Mouse and Animal Pathology Laboratory (MAPLab), Fondazione Filarete, Viale Ortles, 22/4, 20139, Milan, Italy.,Department of Veterinary Medicine, University of Milan, Via Celoria, 10, 20133, Milan, Italy
| | - Alessandro Villa
- Center of Excellence on Neurodegenerative Diseases and Department Pharmacological and Biomolecular Sciences, University of Milan, Via Balzaretti, 9, 20133, Milan, Italy
| | - Adriana Maggi
- Center of Excellence on Neurodegenerative Diseases and Department Pharmacological and Biomolecular Sciences, University of Milan, Via Balzaretti, 9, 20133, Milan, Italy
| | - Elisabetta Vegeto
- Center of Excellence on Neurodegenerative Diseases and Department Pharmacological and Biomolecular Sciences, University of Milan, Via Balzaretti, 9, 20133, Milan, Italy.
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Dual roles of Aβ in proliferative processes in an amyloidogenic model of Alzheimer's disease. Sci Rep 2017; 7:10085. [PMID: 28855626 PMCID: PMC5577311 DOI: 10.1038/s41598-017-10353-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Accepted: 08/08/2017] [Indexed: 12/20/2022] Open
Abstract
Alzheimer’s disease is a major neurodegenerative disorder that leads to severe cognitive deficits in the elderly population. Over the past two decades, multiple studies have focused on elucidating the causative factors underlying memory defects in Alzheimer’s patients. In this regard, new evidence linking Alzheimer’s disease-related pathology and neuronal stem cells suggests that hippocampal neurogenesis impairment is an important factor underlying these cognitive deficits. However, because of conflicting results, the impact of Aβ pathology on neurogenesis/gliogenesis remains unclear. Here, we investigated the effect of Aβ on neuronal and glial proliferation by using an APP/PS1 transgenic model and in vitro assays. Specifically, we showed that neurogenesis is affected early in the APP/PS1 hippocampus, as evidenced by a significant decrease in the proliferative activity due to a reduced number of both radial glia-like neural stem cells (type-1 cells) and intermediate progenitor cells (type-2 cells). Moreover, we demonstrated that soluble Aβ from APP/PS1 mice impairs neuronal cell proliferation using neurosphere cultures. On the other hand, we showed that oligomeric Aβ stimulates microglial proliferation, whereas no effect was observed on astrocytes. These findings indicate that Aβ has a differential effect on hippocampal proliferative cells by inhibiting neuronal proliferation and triggering the formation of microglial cells.
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Developmental toxicant exposure in a mouse model of Alzheimer’s disease induces differential sex-associated microglial activation and increased susceptibility to amyloid accumulation. J Dev Orig Health Dis 2017; 8:493-501. [DOI: 10.1017/s2040174417000277] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
As the resident macrophage of the central nervous system, microglia are thought to contribute to Alzheimer’s disease (AD) pathology through lack of neuroprotection. The role of immune dysfunction in AD may be due to disruption of regulatory signals for the activation of microglia that may occur early in development. We hypothesized that early toxicant exposure would systematically activate microglia, possibly reversing the pathological severity of AD. Offspring of a triple transgenic murine model for AD (3×TgAD) were exposed to a model neurotoxicant, lead acetate, from postnatal days (PND) 5–10. Our results indicated that female mice exposed to Pb had a greater and earlier incidence of amyloid burden within the hippocampus, coinciding with decreased markers of microglial activation at PND 50. Pb-exposed males had increased microglial activation at PND 50, as evidence by CD11b expression and microglial abundance, with no significant increase in amyloid burden at that time. There was greater amyloid burden at PND 90 and 180 in both male and female mice exposed to Pb compared with control. Together, these data suggest that activated microglia are neuroprotective against amyloid accumulation early in AD pathology, and that early exposure to Pb could increase susceptibility to later-life neurodegeneration. Likewise, females may be more susceptible to early-life microglial damage, and, subsequently, AD. Further investigation into the sex biased mechanisms by which microglial activation is altered by an early-life immune insult will provide critical insight into the temporal susceptibility of the developing neuroimmune system and its potential role in AD etiopathology.
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Dupont AC, Largeau B, Santiago Ribeiro MJ, Guilloteau D, Tronel C, Arlicot N. Translocator Protein-18 kDa (TSPO) Positron Emission Tomography (PET) Imaging and Its Clinical Impact in Neurodegenerative Diseases. Int J Mol Sci 2017; 18:ijms18040785. [PMID: 28387722 PMCID: PMC5412369 DOI: 10.3390/ijms18040785] [Citation(s) in RCA: 119] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 03/31/2017] [Accepted: 04/04/2017] [Indexed: 02/06/2023] Open
Abstract
In vivo exploration of activated microglia in neurodegenerative diseases is achievable by Positron Emission Tomography (PET) imaging, using dedicated radiopharmaceuticals targeting the translocator protein-18 kDa (TSPO). In this review, we emphasized the major advances made over the last 20 years, thanks to TSPO PET imaging, to define the pathophysiological implication of microglia activation and neuroinflammation in neurodegenerative diseases, including Parkinson’s disease, Huntington’s disease, dementia, amyotrophic lateral sclerosis, multiple sclerosis, and also in psychiatric disorders. The extent and upregulation of TSPO as a molecular biomarker of activated microglia in the human brain is now widely documented in these pathologies, but its significance, and especially its protective or deleterious action regarding the disease’s stage, remains under debate. Thus, we exposed new and plausible suggestions to enhance the contribution of TSPO PET imaging for biomedical research by exploring microglia’s role and interactions with other cells in brain parenchyma. Multiplex approaches, associating TSPO PET radiopharmaceuticals with other biomarkers (PET imaging of cellular metabolism, neurotransmission or abnormal protein aggregates, but also other imaging modalities, and peripheral cytokine levels measurement and/or metabolomics analysis) was considered. Finally, the actual clinical impact of TSPO PET imaging as a routine biomarker of neuroinflammation was put into perspective regarding the current development of diagnostic and therapeutic strategies for neurodegenerative diseases.
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Affiliation(s)
- Anne-Claire Dupont
- CHRU Tours, 2 Boulevard Tonnellé, 37044 Tours, France.
- Institut National de la Santé et de la Recherche Médicale U930, 10 Boulevard Tonnellé, 37032 Tours, France.
| | | | - Maria Joao Santiago Ribeiro
- CHRU Tours, 2 Boulevard Tonnellé, 37044 Tours, France.
- Institut National de la Santé et de la Recherche Médicale U930, 10 Boulevard Tonnellé, 37032 Tours, France.
| | - Denis Guilloteau
- CHRU Tours, 2 Boulevard Tonnellé, 37044 Tours, France.
- Institut National de la Santé et de la Recherche Médicale U930, 10 Boulevard Tonnellé, 37032 Tours, France.
| | - Claire Tronel
- Institut National de la Santé et de la Recherche Médicale U930, 10 Boulevard Tonnellé, 37032 Tours, France.
| | - Nicolas Arlicot
- CHRU Tours, 2 Boulevard Tonnellé, 37044 Tours, France.
- Institut National de la Santé et de la Recherche Médicale U930, 10 Boulevard Tonnellé, 37032 Tours, France.
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Schain M, Kreisl WC. Neuroinflammation in Neurodegenerative Disorders—a Review. Curr Neurol Neurosci Rep 2017; 17:25. [DOI: 10.1007/s11910-017-0733-2] [Citation(s) in RCA: 187] [Impact Index Per Article: 26.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Griffith CM, Xie MX, Qiu WY, Sharp AA, Ma C, Pan A, Yan XX, Patrylo PR. Aberrant expression of the pore-forming KATP channel subunit Kir6.2 in hippocampal reactive astrocytes in the 3xTg-AD mouse model and human Alzheimer’s disease. Neuroscience 2016; 336:81-101. [DOI: 10.1016/j.neuroscience.2016.08.034] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Revised: 08/15/2016] [Accepted: 08/20/2016] [Indexed: 12/21/2022]
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McMillin M, Grant S, Frampton G, Andry S, Brown A, DeMorrow S. Fractalkine suppression during hepatic encephalopathy promotes neuroinflammation in mice. J Neuroinflammation 2016; 13:198. [PMID: 27561705 PMCID: PMC5000400 DOI: 10.1186/s12974-016-0674-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Accepted: 08/17/2016] [Indexed: 12/31/2022] Open
Abstract
Background Acute liver failure is associated with numerous systemic consequences including neurological dysfunction, termed hepatic encephalopathy, which contributes to mortality and is a challenge to manage in the clinic. During hepatic encephalopathy, microglia activation and neuroinflammation occur due to dysregulated cell signaling and an increase of toxic metabolites in the brain. Fractalkine is a chemokine that is expressed primarily in neurons and through signaling with its receptor CX3CR1 on microglia, leads to microglia remaining in a quiescent state. Fractalkine is often suppressed during neuropathies that are characterized by neuroinflammation. However, the expression and subsequent role of fractalkine on microglia activation and the pathogenesis of hepatic encephalopathy due to acute liver failure is unknown. Methods Hepatic encephalopathy was induced in mice via injection of azoxymethane (AOM) or saline for controls. Subsets of these mice were implanted with osmotic minipumps that infused soluble fractalkine or saline into the lateral ventricle of the brain. Neurological decline and the latency to coma were recorded in these mice, and brain, serum, and liver samples were collected. Neurons or microglia were isolated from whole brain samples using immunoprecipitation. Liver damage was assessed using hematoxylin and eosin staining and by measuring serum liver enzyme concentrations. Fractalkine and CX3CR1 expression were assessed by real-time PCR, and proinflammatory cytokine expression was assessed using ELISA assays. Results Following AOM administration, fractalkine expression is suppressed in the cortex and in isolated neurons compared to vehicle-treated mice. CX3CR1 is suppressed in isolated microglia from AOM-treated mice. Soluble fractalkine infusion into the brain significantly reduced neurological decline in AOM-treated mice compared to saline-infused AOM-treated mice. Infusion of soluble fractalkine into AOM-treated mice reduced liver damage, lessened microglia activation, and suppressed expression of chemokine ligand 2, interleukin-6, and tumor necrosis factor alpha compared to saline-infused mice. Conclusions These findings suggest that fractalkine-mediated signaling is suppressed in the brain following the development of hepatic encephalopathy. Supplementation of AOM-treated mice with soluble fractalkine led to improved outcomes, which identifies this pathway as a possible therapeutic target for the management of hepatic encephalopathy following acute liver injury.
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Affiliation(s)
- Matthew McMillin
- Department of Internal Medicine, Texas A&M Health Science Center, College of Medicine, Temple, TX, USA.,Central Texas Veterans Healthcare System, 1901 S. 1st Street, Building 205, Temple, TX, 76504, USA
| | - Stephanie Grant
- Department of Internal Medicine, Texas A&M Health Science Center, College of Medicine, Temple, TX, USA.,Central Texas Veterans Healthcare System, 1901 S. 1st Street, Building 205, Temple, TX, 76504, USA
| | - Gabriel Frampton
- Department of Internal Medicine, Texas A&M Health Science Center, College of Medicine, Temple, TX, USA.,Central Texas Veterans Healthcare System, 1901 S. 1st Street, Building 205, Temple, TX, 76504, USA
| | - Sarah Andry
- Department of Internal Medicine, Baylor Scott & White Health, 2401 S. 31st Street, Temple, TX, 76508, USA
| | - Adam Brown
- Department of Internal Medicine, Baylor Scott & White Health, 2401 S. 31st Street, Temple, TX, 76508, USA
| | - Sharon DeMorrow
- Department of Internal Medicine, Texas A&M Health Science Center, College of Medicine, Temple, TX, USA. .,Central Texas Veterans Healthcare System, 1901 S. 1st Street, Building 205, Temple, TX, 76504, USA.
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Murray HC, Low VF, Swanson ME, Dieriks BV, Turner C, Faull RL, Curtis MA. Distribution of PSA-NCAM in normal, Alzheimer’s and Parkinson’s disease human brain. Neuroscience 2016; 330:359-75. [DOI: 10.1016/j.neuroscience.2016.06.003] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Revised: 06/01/2016] [Accepted: 06/02/2016] [Indexed: 12/25/2022]
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Liu H, Song N. Molecular Mechanism of Adult Neurogenesis and its Association with Human Brain Diseases. J Cent Nerv Syst Dis 2016; 8:5-11. [PMID: 27375363 PMCID: PMC4915785 DOI: 10.4137/jcnsd.s32204] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Revised: 04/07/2016] [Accepted: 05/30/2016] [Indexed: 12/19/2022] Open
Abstract
Recent advances in neuroscience challenge the old dogma that neurogenesis occurs only during embryonic development. Mounting evidence suggests that functional neurogenesis occurs throughout adulthood. This review article discusses molecular factors that affect adult neurogenesis, including morphogens, growth factors, neurotransmitters, transcription factors, and epigenetic factors. Furthermore, we summarize and compare current evidence of associations between adult neurogenesis and human brain diseases such as Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, and brain tumors.
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Affiliation(s)
- He Liu
- Department of Biology, Morosky College of Health Professions and Sciences, Gannon University, Erie, PA, USA
| | - Ni Song
- Division of Health Sciences & Workforce Technology, Lamar State College-Orange, Orange, TX, USA
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Mastroeni D, Chouliaras L, Van den Hove DL, Nolz J, Rutten BP, Delvaux E, Coleman. PD. Increased 5-hydroxymethylation levels in the sub ventricular zone of the Alzheimer's brain. ACTA ACUST UNITED AC 2016. [DOI: 10.1016/j.nepig.2016.04.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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