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Fan Y, He X, Chen M, Guo S, Dong Z. Pterostilbene alleviates MPTP-induced neurotoxicity by targeting neuroinflammation and oxidative stress. Biochem Biophys Res Commun 2024; 729:150358. [PMID: 38981401 DOI: 10.1016/j.bbrc.2024.150358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2024] [Revised: 06/13/2024] [Accepted: 07/04/2024] [Indexed: 07/11/2024]
Abstract
Pterostilbene (PTE), a naturally occurring phenolic compound primarily found in blueberries, demonstrates neuroprotective properties. However, the role of PTE in Parkinson's disease (PD) remains unclear. This study aimed to investigate the neuroprotective role of PTE in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD animal model. Our findings demonstrate that administering PTE effectively reversed the diminished levels of dopamine in the striatum, thereby ameliorating motor impairments in the MPTP model. Moreover, PTE administration mitigated the loss of dopaminergic (DA) neurons and reduced the upregulation of α-synuclein (α-syn) induced by MPTP. Mechanistic analysis revealed that PTE administration inhibited the activation of microglia and astrocytes, as well as pro-inflammatory factors such as TNF-α and IL-1β in the MPTP model. Additionally, PTE administration decreased MPTP-induced levels of reactive oxygen species (ROS) and malondialdehyde (MDA), while increasing total antioxidant capacity (TAOC) and superoxide dismutase (SOD) activity, thereby attenuating oxidative stress. Collectively, these findings demonstrate that PTE exerts neuroprotective effects in the MPTP mouse model of PD by suppressing neuroinflammation and oxidative stress. Thus, PTE holds promise as a therapeutic agent for PD.
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Affiliation(s)
- Yepeng Fan
- Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, Chongqing Key Laboratory of Child Neurodevelopment and Cognitive Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, China
| | - Xin He
- Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, Chongqing Key Laboratory of Child Neurodevelopment and Cognitive Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, China
| | - Mulan Chen
- Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, Chongqing Key Laboratory of Child Neurodevelopment and Cognitive Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, China
| | - Song Guo
- Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, Chongqing Key Laboratory of Child Neurodevelopment and Cognitive Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, China
| | - Zhifang Dong
- Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, Chongqing Key Laboratory of Child Neurodevelopment and Cognitive Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, China.
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2
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Adhikari A, Chauhan K, Adhikari M, Tiwari AK. Colony Stimulating Factor-1 Receptor: An emerging target for neuroinflammation PET imaging and AD therapy. Bioorg Med Chem 2024; 100:117628. [PMID: 38330850 DOI: 10.1016/j.bmc.2024.117628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 01/01/2024] [Accepted: 01/29/2024] [Indexed: 02/10/2024]
Abstract
Although neuroinflammation is a significant pathogenic feature of many neurologic disorders, its precise function in-vivo is still not completely known. PET imaging enables the longitudinal examination, quantification, and tracking of different neuroinflammation biomarkers in living subjects. Particularly, PET imaging of Microglia, specialised dynamic immune cells crucial for maintaining brain homeostasis in central nervous system (CNS), is crucial for staging the neuroinflammation. Colony Stimulating Factor- 1 Receptor (CSF-1R) PET imaging is a novel method for the quantification of neuroinflammation. CSF-1R is mainly expressed on microglia, and neurodegenerative disorders greatly up-regulate its expression. The present review primarily focuses on the development, pros and cons of all the CSF-1R PET tracers reported for neuroinflammation imaging. Apart from neuroinflammation imaging, CSF-1R inhibitors are also reported for the therapy of neurodegenerative diseases such as Alzheimer's disease (AD). AD is a prevalent, advancing, and fatal neurodegenerative condition that have the characteristic feature of persistent neuroinflammation and primarily affects the elderly. The aetiology of AD is profoundly influenced by amyloid-beta (Aβ) plaques, intracellular neurofibrillary tangles, and microglial dysfunction. Increasing evidence suggests that CSF-1R inhibitors (CSF-1Ri) can be helpful in preclinical models of neurodegenerative diseases. This review article also summarises the most recent developments of CSF-1Ri-based therapy for AD.
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Affiliation(s)
- Anupriya Adhikari
- Department of Chemistry, Graphic Era Hill University, Clement Town, Dehradun, Uttarakhand, India.
| | - Kanchan Chauhan
- Centro de Nanociencias y Nanotecnología, Universidad Nacional Autónoma de México, Km 107 carretera, Tijuana-Ensenada, Baja California 22860, Mexico
| | - Manish Adhikari
- Department of Physiology and Cell Biology, University of Arkansas for Medical Sciences, Little Rock, AR, United States
| | - Anjani K Tiwari
- Department of Chemistry, Babasaheb, Bhimrao Ambedkar University, Lucknow, Uttar Pradesh, India
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3
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Etebar F, Harkin DG, White AR, Dando SJ. Non-invasive in vivo imaging of brain and retinal microglia in neurodegenerative diseases. Front Cell Neurosci 2024; 18:1355557. [PMID: 38348116 PMCID: PMC10859418 DOI: 10.3389/fncel.2024.1355557] [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: 12/14/2023] [Accepted: 01/10/2024] [Indexed: 02/15/2024] Open
Abstract
Microglia play crucial roles in immune responses and contribute to fundamental biological processes within the central nervous system (CNS). In neurodegenerative diseases, microglia undergo functional changes and can have both protective and pathogenic roles. Microglia in the retina, as an extension of the CNS, have also been shown to be affected in many neurological diseases. While our understanding of how microglia contribute to pathological conditions is incomplete, non-invasive in vivo imaging of brain and retinal microglia in living subjects could provide valuable insights into their role in the neurodegenerative diseases and open new avenues for diagnostic biomarkers. This mini-review provides an overview of the current brain and retinal imaging tools for studying microglia in vivo. We focus on microglia targets, the advantages and limitations of in vivo microglia imaging approaches, and applications for evaluating the pathogenesis of neurological conditions, such as Alzheimer's disease and multiple sclerosis.
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Affiliation(s)
- Fazeleh Etebar
- Centre for Immunology and Infection Control, School of Biomedical Sciences, Faculty of Health, Queensland University of Technology (QUT), Brisbane, QLD, Australia
- Mental Health and Neuroscience Program, QIMR Berghofer Medical Research Institute, Herston, QLD, Australia
| | - Damien G. Harkin
- Centre for Vision and Eye Research, School of Biomedical Sciences, Faculty of Health, Queensland University of Technology (QUT), Brisbane, QLD, Australia
| | - Anthony R. White
- Mental Health and Neuroscience Program, QIMR Berghofer Medical Research Institute, Herston, QLD, Australia
| | - Samantha J. Dando
- Centre for Immunology and Infection Control, School of Biomedical Sciences, Faculty of Health, Queensland University of Technology (QUT), Brisbane, QLD, Australia
- Centre for Vision and Eye Research, School of Biomedical Sciences, Faculty of Health, Queensland University of Technology (QUT), Brisbane, QLD, Australia
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4
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Oh J, Airas L, Harrison D, Järvinen E, Livingston T, Lanker S, Malik RA, Okuda DT, Villoslada P, de Vries HE. Neuroimaging to monitor worsening of multiple sclerosis: advances supported by the grant for multiple sclerosis innovation. Front Neurol 2023; 14:1319869. [PMID: 38107636 PMCID: PMC10722910 DOI: 10.3389/fneur.2023.1319869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Accepted: 11/13/2023] [Indexed: 12/19/2023] Open
Abstract
Key unmet needs in multiple sclerosis (MS) include detection of early pathology, disability worsening independent of relapses, and accurate monitoring of treatment response. Collaborative approaches to address these unmet needs have been driven in part by industry-academic networks and initiatives such as the Grant for Multiple Sclerosis Innovation (GMSI) and Multiple Sclerosis Leadership and Innovation Network (MS-LINK™) programs. We review the application of recent advances, supported by the GMSI and MS-LINK™ programs, in neuroimaging technology to quantify pathology related to central pathology and disease worsening, and potential for their translation into clinical practice/trials. GMSI-supported advances in neuroimaging methods and biomarkers include developments in magnetic resonance imaging, positron emission tomography, ocular imaging, and machine learning. However, longitudinal studies are required to facilitate translation of these measures to the clinic and to justify their inclusion as endpoints in clinical trials of new therapeutics for MS. Novel neuroimaging measures and other biomarkers, combined with artificial intelligence, may enable accurate prediction and monitoring of MS worsening in the clinic, and may also be used as endpoints in clinical trials of new therapies for MS targeting relapse-independent disease pathology.
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Affiliation(s)
- Jiwon Oh
- Division of Neurology, St. Michael’s Hospital, Department of Medicine, University of Toronto, Toronto, ON, Canada
- Department of Neurology, Johns Hopkins University, Baltimore, MD, United States
| | - Laura Airas
- Turku PET Centre, Turku University Hospital and University of Turku, Turku, Finland
- Division of Clinical Neurosciences, Turku University Hospital and University of Turku, Turku, Finland
| | - Daniel Harrison
- Department of Neurology, University of Maryland School of Medicine, Baltimore, MD, United States
- Baltimore VA Medical Center, VA Maryland Healthcare System, Baltimore, MD, United States
| | - Elina Järvinen
- Neurology and Immunology, Medical Unit N&I, Merck OY (an affiliate of Merck KGaA), Espoo, Finland
| | - Terrie Livingston
- Patient Solutions and Center of Excellence Strategic Engagement, EMD Serono, Inc., Rockland, MA, United States
| | - Stefan Lanker
- Neurology & Immunology, US Medical Affairs, EMD Serono Research & Development Institute, Inc., (an affiliate of Merck KGaA), Billerica, MA, United States
| | - Rayaz A. Malik
- Weill Cornell Medicine-Qatar, Research Division, Doha, Qatar
- Institute of Cardiovascular Sciences, University of Manchester, Manchester, United Kingdom
| | - Darin T. Okuda
- Department of Neurology, Neuroinnovation Program, Multiple Sclerosis and Neuroimmunology Imaging Program, Clinical Center for Multiple Sclerosis, UT Southwestern Medical Center, Dallas, TX, United States
| | - Pablo Villoslada
- August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain
| | - Helga E. de Vries
- MS Center Amsterdam, Department of Molecular Cell Biology and Immunology, Vrije Universiteit Amsterdam, Amsterdam Neuroscience, Amsterdam University Medical Centers (Amsterdam UMC), Location VUmc, Amsterdam, Netherlands
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5
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Haider A, Wang L, Gobbi L, Li Y, Chaudhary A, Zhou X, Chen J, Zhao C, Rong J, Xiao Z, Hou L, Elghazawy NH, Sippl W, Davenport AT, Daunais JB, Ahmed H, Crowe R, Honer M, Rominger A, Grether U, Liang SH, Ametamey SM. Evaluation of [ 18F]RoSMA-18-d 6 as a CB2 PET Radioligand in Nonhuman Primates. ACS Chem Neurosci 2023; 14:3752-3760. [PMID: 37788055 DOI: 10.1021/acschemneuro.3c00222] [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] [Indexed: 10/04/2023] Open
Abstract
The cannabinoid type 2 receptor (CB2) has been implicated in a variety of central and peripheral inflammatory diseases, prompting significant interest in the development of CB2-targeted diagnostic and therapeutic agents. A validated positron emission tomography (PET) radioligand for imaging CB2 in the living human brain as well as in peripheral tissues is currently lacking. As part of our research program, we have recently identified the trisubstituted pyridine, [18F]RoSMA-18-d6, which proved to be highly suitable for in vitro and in vivo mapping of CB2 in rodents. The aim of this study was to assess the performance characteristics of [18F]RoSMA-18-d6 in nonhuman primates (NHPs) to pave the way for clinical translation. [18F]RoSMA-18-d6 was synthesized from the respective tosylate precursor according to previously reported procedures. In vitro autoradiograms with NHP spleen tissue sections revealed a high binding of [18F]RoSMA-18-d6 to the CB2-rich NHP spleen, which was significantly blocked by coincubation with the commercially available CB2 ligand, GW405833 (10 μM). In contrast, no specific binding was observed by in vitro autoradiography with NHP brain sections, which was in agreement with the notion of a CB2-deficient healthy mammalian brain. In vitro findings were corroborated by PET imaging experiments in NHPs, where [18F]RoSMA-18-d6 uptake in the spleen was dose-dependently attenuated with 1 and 5 mg/kg GW405833, while no specific brain signal was observed. Remarkably, we observed tracer uptake and retention in the NHP spinal cord, which was reduced by GW405833 blockade, pointing toward a potential utility of [18F]RoSMA-18-d6 in probing CB2-expressing cells in the bone marrow. If these observations are substantiated in NHP models of enhanced leukocyte proliferation in the bone marrow, [18F]RoSMA-18-d6 may serve as a valuable marker for hematopoietic activity in various pathologies. In conclusion, [18F]RoSMA-18-d6 proved to be a suitable PET radioligand for imaging CB2 in NHPs, supporting its translation to humans.
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Affiliation(s)
- Ahmed Haider
- Department of Radiology, Division of Nuclear Medicine and Molecular Imaging Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, Boston, Massachusetts 02114, United States
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Road, Atlanta, Georgia 30322, United States
| | - Lu Wang
- Center of Cyclotron and PET Radiopharmaceuticals, Department of Nuclear Medicine and PET/CT-MRI Center, The First Affiliated Hospital of Jinan University, Guangzhou 510630, China
| | - Luca Gobbi
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche, 4070 Basel, Switzerland
| | - Yinlong Li
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Road, Atlanta, Georgia 30322, United States
| | - Ahmad Chaudhary
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Road, Atlanta, Georgia 30322, United States
| | - Xin Zhou
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Road, Atlanta, Georgia 30322, United States
| | - Jiahui Chen
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Road, Atlanta, Georgia 30322, United States
| | - Chunyu Zhao
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Road, Atlanta, Georgia 30322, United States
| | - Jian Rong
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Road, Atlanta, Georgia 30322, United States
| | - Zhiwei Xiao
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Road, Atlanta, Georgia 30322, United States
| | - Lu Hou
- Center of Cyclotron and PET Radiopharmaceuticals, Department of Nuclear Medicine and PET/CT-MRI Center, The First Affiliated Hospital of Jinan University, Guangzhou 510630, China
| | - Nehal H Elghazawy
- Institute of Pharmacy, Department of Medicinal Chemistry, Martin-Luther-University Halle-Wittenberg, W.-Langenbeck-Str. 4, 06120 Halle, Germany
| | - Wolfgang Sippl
- Institute of Pharmacy, Department of Medicinal Chemistry, Martin-Luther-University Halle-Wittenberg, W.-Langenbeck-Str. 4, 06120 Halle, Germany
| | - April T Davenport
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston Salem, North Carolina 27157, United States
| | - James B Daunais
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston Salem, North Carolina 27157, United States
| | - Hazem Ahmed
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Institute of Pharmaceutical Sciences ETH, Vladimir-Prelog-Weg 4, 8093 Zurich, Switzerland
| | - Ron Crowe
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Road, Atlanta, Georgia 30322, United States
| | - Michael Honer
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche, 4070 Basel, Switzerland
| | - Axel Rominger
- Department of Nuclear Medicine, Bern University Hospital, 3010 Bern, Switzerland
| | - Uwe Grether
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche, 4070 Basel, Switzerland
| | - Steven H Liang
- Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Road, Atlanta, Georgia 30322, United States
| | - Simon M Ametamey
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Institute of Pharmaceutical Sciences ETH, Vladimir-Prelog-Weg 4, 8093 Zurich, Switzerland
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6
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Self WK, Holtzman DM. Emerging diagnostics and therapeutics for Alzheimer disease. Nat Med 2023; 29:2187-2199. [PMID: 37667136 DOI: 10.1038/s41591-023-02505-2] [Citation(s) in RCA: 43] [Impact Index Per Article: 43.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 07/18/2023] [Indexed: 09/06/2023]
Abstract
Alzheimer disease (AD) is the most common contributor to dementia in the world, but strategies that slow or prevent its clinical progression have largely remained elusive, until recently. This Review highlights the latest advances in biomarker technologies and therapeutic development to improve AD diagnosis and treatment. We review recent results that enable pathological staging of AD with neuroimaging and fluid-based biomarkers, with a particular emphasis on the role of amyloid, tau and neuroinflammation in disease pathogenesis. We discuss the lessons learned from randomized controlled trials, including some supporting the proposal that certain anti-amyloid antibodies slow cognitive decline during the mildly symptomatic phase of AD. In addition, we highlight evidence for newly identified therapeutic targets that may be able to modify AD pathogenesis and progression. Collectively, these recent discoveries-and the research directions that they open-have the potential to move AD clinical care toward disease-modifying treatment strategies with maximal benefits for patients.
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Affiliation(s)
- Wade K Self
- Department of Neurology, Hope Center for Neurological Disorders, Knight Alzheimer's Disease Research Center, Washington University School of Medicine, St. Louis, MO, USA
| | - David M Holtzman
- Department of Neurology, Hope Center for Neurological Disorders, Knight Alzheimer's Disease Research Center, Washington University School of Medicine, St. Louis, MO, USA.
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7
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Yu C, Deng XJ, Xu D. Microglia in epilepsy. Neurobiol Dis 2023; 185:106249. [PMID: 37536386 DOI: 10.1016/j.nbd.2023.106249] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 07/07/2023] [Accepted: 07/31/2023] [Indexed: 08/05/2023] Open
Abstract
Epilepsy is one of most common chronic neurological disorders, and the antiseizure medications developed by targeting neurocentric mechanisms have not effectively reduced the proportion of patients with drug-resistant epilepsy. Further exploration of the cellular or molecular mechanism of epilepsy is expected to provide new options for treatment. Recently, more and more researches focus on brain network components other than neurons, among which microglia have attracted much attention for their diverse biological functions. As the resident immune cells of the central nervous system, microglia have highly plastic transcription, morphology and functional characteristics, which can change dynamically in a context-dependent manner during the progression of epilepsy. In the pathogenesis of epilepsy, highly reactive microglia interact with other components in the epileptogenic network by performing crucial functions such as secretion of soluble factors and phagocytosis, thus continuously reshaping the landscape of the epileptic brain microenvironment. Indeed, microglia appear to be both pro-epileptic and anti-epileptic under the different spatiotemporal contexts of disease, rendering interventions targeting microglia biologically complex and challenging. This comprehensive review critically summarizes the pathophysiological role of microglia in epileptic brain homeostasis alterations and explores potential therapeutic or modulatory targets for epilepsy targeting microglia.
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Affiliation(s)
- Cheng Yu
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, Hubei Province 430022, China
| | - Xue-Jun Deng
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, Hubei Province 430022, China
| | - Da Xu
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, Hubei Province 430022, China.
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8
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Zhang X, Chen F, Sun M, Wu N, Liu B, Yi X, Ge R, Fan X. Microglia in the context of multiple sclerosis. Front Neurol 2023; 14:1157287. [PMID: 37360338 PMCID: PMC10287974 DOI: 10.3389/fneur.2023.1157287] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 05/10/2023] [Indexed: 06/28/2023] Open
Abstract
Multiple sclerosis (MS) is an inflammatory and neurodegenerative disease that commonly results in nontraumatic disability in young adults. The characteristic pathological hallmark of MS is damage to myelin, oligodendrocytes, and axons. Microglia provide continuous surveillance in the CNS microenvironment and initiate defensive mechanisms to protect CNS tissue. Additionally, microglia participate in neurogenesis, synaptic refinement, and myelin pruning through the expression and release of different signaling factors. Continuous activation of microglia has been implicated in neurodegenerative disorders. We first review the lifetime of microglia, including the origin, differentiation, development, and function of microglia. We then discuss microglia participate in the whole processes of remyelination and demyelination, microglial phenotypes in MS, and the NF-κB/PI3K-AKT signaling pathway in microglia. The damage to regulatory signaling pathways may change the homeostasis of microglia, which would accelerate the progression of MS.
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Affiliation(s)
- Xue Zhang
- Department of Neurology, Binzhou Medical University Hospital, Binzhou, China
| | - Fang Chen
- Department of Neurology, Binzhou Medical University Hospital, Binzhou, China
| | - Mingyue Sun
- Department of Neurology, Binzhou Medical University Hospital, Binzhou, China
| | - Nan Wu
- Department of Neurology, Binzhou Medical University Hospital, Binzhou, China
| | - Bin Liu
- Institute for Metabolic and Neuropsychiatric Disorders, Binzhou Medical University Hospital, Binzhou, China
| | - Xiangming Yi
- Department of Neurology, Binzhou Medical University Hospital, Binzhou, China
| | - Ruli Ge
- Department of Neurology, Binzhou Medical University Hospital, Binzhou, China
| | - Xueli Fan
- Department of Neurology, Binzhou Medical University Hospital, Binzhou, China
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9
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Fujikawa R, Tsuda M. The Functions and Phenotypes of Microglia in Alzheimer's Disease. Cells 2023; 12:cells12081207. [PMID: 37190116 DOI: 10.3390/cells12081207] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 04/17/2023] [Accepted: 04/20/2023] [Indexed: 05/17/2023] Open
Abstract
Alzheimer's disease (AD) is the most prevalent neurodegenerative disease worldwide, but therapeutic strategies to slow down AD pathology and symptoms have not yet been successful. While attention has been focused on neurodegeneration in AD pathogenesis, recent decades have provided evidence of the importance of microglia, and resident immune cells in the central nervous system. In addition, new technologies, including single-cell RNA sequencing, have revealed heterogeneous cell states of microglia in AD. In this review, we systematically summarize the microglial response to amyloid-β and tau tangles, and the risk factor genes expressed in microglia. Furthermore, we discuss the characteristics of protective microglia that appear during AD pathology and the relationship between AD and microglia-induced inflammation during chronic pain. Understanding the diverse roles of microglia will help identify new therapeutic strategies for AD.
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Affiliation(s)
- Risako Fujikawa
- Department of Molecular and System Pharmacology, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka 812-8582, Japan
| | - Makoto Tsuda
- Department of Molecular and System Pharmacology, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka 812-8582, Japan
- Kyushu University Institute for Advanced Study, Fukuoka 819-0395, Japan
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10
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Ni R. PET imaging in animal models of Parkinson's disease. Behav Brain Res 2023; 438:114174. [PMID: 36283568 DOI: 10.1016/j.bbr.2022.114174] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Revised: 09/20/2022] [Accepted: 09/27/2022] [Indexed: 12/05/2022]
Abstract
Alpha-synucleinopathies, such as Parkinson's disease, dementia with Lewy bodies and multiple system atrophy, are characterized by aberrant accumulation of alpha-synuclein and synaptic dysfunction leading to motor and cognitive deficits. Animal models of alpha-synucleinopathy have greatly facilitated the mechanistic understanding of the disease and the development of therapeutics. Various transgenic, alpha-synuclein fibril-injected, and toxin-injected animal models of Parkinson's disease and multiple system atrophy that recapitulate the disease pathology have been developed and widely used. Recent advances in positron emission tomography have allowed the noninvasive visualization of molecular alterations, underpinning behavioral dysfunctions in the brains of animal models and the longitudinal monitoring of treatment effects. Imaging studies in these disease animal models have employed multi-tracer PET designs to reveal dopaminergic deficits together with other molecular alterations. This review focuses on the development of new positron emission tomography tracers and studies of alpha-synuclein, synaptic vesicle glycoprotein 2A neurotransmitter receptor deficits such as dopaminergic receptor, dopaminergic transporter, serotonergic receptor, vesicular monoamine transporter 2, hypometabolism, neuroinflammation, mitochondrial dysfunction and leucine rich repeat kinase 2 in animal models of Parkinson's disease. The outstanding challenges and emerging applications are outlined, such as investigating the gut-brain-axis by using positron emission tomography in animal models, and provide a future outlook.
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Affiliation(s)
- Ruiqing Ni
- Institute for Regenerative Medicine, University of Zurich, Zurich, Switzerland; Institute for Biomedical Engineering, University of Zurich & ETH Zurich, Zurich, Switzerland.
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11
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Roseborough AD, Myers SJ, Khazaee R, Zhu Y, Zhao L, Iorio E, Elahi FM, Pasternak SH, Whitehead SN. Plasma derived extracellular vesicle biomarkers of microglia activation in an experimental stroke model. J Neuroinflammation 2023; 20:20. [PMID: 36721258 PMCID: PMC9890769 DOI: 10.1186/s12974-023-02708-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 01/27/2023] [Indexed: 02/02/2023] Open
Abstract
Chronic microglia activation post-stroke is associated with worse neurological and cognitive outcomes. However, measurement of microglia activation in vivo is currently limited. Plasma derived extracellular vesicles (EVs) are cell-specific indicators that may allow for non-invasive measurement of microglia phenotype. The aim of this study was to identify activation-state specific microglia EVs (MEVs) in vitro followed by validation in an experimental stroke model. Following pro-inflammatory activation, MEVs contain the microglia protein TMEM119 alongside increased expression of the Toll-like receptor 4 co-receptor CD14. Immunoprecipitation followed by fluorescent nanoparticle tracking analysis (ONI Nanoimager) was used to confirm the isolation of TMEM119+/CD14+ EVs from rat plasma. Electron microscopy confirmed that TMEM119 and CD14 localize to the MEV membrane. To model ischemia, plasma was collected from 3-month wildtype Fischer344 rats prior to, 7 and 28 days after endothelin-1 or saline injection into the dorsal right striatum. Fluorescently labelled MEVs were directly measured in the plasma using nanoflow cytometry (Apogee A60 Microplus). We report a significant increase in circulating TMEM119+/CD14+ EVs 28-days post-stroke in comparison to baseline levels and saline-injected rats, which correlated weakly with stroke volume. TMEM119+/MHC-II+ EVs were also increased post-stroke in comparison to baseline and saline-injected animals. This study is the first to describe an EV biomarker of activated microglia detected directly in plasma following stroke and represents a future tool for the measurement of microglia activity in vivo.
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Affiliation(s)
- A. D. Roseborough
- grid.39381.300000 0004 1936 8884Vulnerable Brain Laboratory, Department of Anatomy and Cell Biology, The Schulich School of Medicine and Dentistry, The University of Western Ontario, 458 Medical Sciences Building, ON N6A 3K London, Canada
| | - S. J. Myers
- grid.39381.300000 0004 1936 8884Vulnerable Brain Laboratory, Department of Anatomy and Cell Biology, The Schulich School of Medicine and Dentistry, The University of Western Ontario, 458 Medical Sciences Building, ON N6A 3K London, Canada
| | - R. Khazaee
- grid.39381.300000 0004 1936 8884Biotron Integrated Microscopy Facility, The University of Western Ontario, London, ON Canada ,grid.39381.300000 0004 1936 8884Deparment of Biology, The University of Western Ontario, London, ON Canada
| | - Y. Zhu
- grid.39381.300000 0004 1936 8884Vulnerable Brain Laboratory, Department of Anatomy and Cell Biology, The Schulich School of Medicine and Dentistry, The University of Western Ontario, 458 Medical Sciences Building, ON N6A 3K London, Canada
| | - L. Zhao
- grid.39381.300000 0004 1936 8884Vulnerable Brain Laboratory, Department of Anatomy and Cell Biology, The Schulich School of Medicine and Dentistry, The University of Western Ontario, 458 Medical Sciences Building, ON N6A 3K London, Canada
| | - E. Iorio
- grid.266102.10000 0001 2297 6811Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA USA
| | - F. M. Elahi
- grid.266102.10000 0001 2297 6811Weill Institute for Neurosciences, University of California San Francisco, San Francisco, CA USA ,grid.59734.3c0000 0001 0670 2351Icahn School of Medicine at Mount Sinai, New York, USA ,grid.39381.300000 0004 1936 8884Department of Clinical Neurological Sciences, The Schulich School of Medicine and Dentistry, The University of Western Ontario, ON London, Canada
| | - S. H. Pasternak
- grid.59734.3c0000 0001 0670 2351Icahn School of Medicine at Mount Sinai, New York, USA ,grid.39381.300000 0004 1936 8884Department of Clinical Neurological Sciences, The Schulich School of Medicine and Dentistry, The University of Western Ontario, ON London, Canada ,grid.39381.300000 0004 1936 8884Robarts Research Institute, The Schulich School of Medicine and Dentistry, The University of Western Ontario, ON London, Canada
| | - S. N. Whitehead
- grid.39381.300000 0004 1936 8884Vulnerable Brain Laboratory, Department of Anatomy and Cell Biology, The Schulich School of Medicine and Dentistry, The University of Western Ontario, 458 Medical Sciences Building, ON N6A 3K London, Canada
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12
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ImmunoPET Directed to the Brain: A New Tool for Preclinical and Clinical Neuroscience. Biomolecules 2023; 13:biom13010164. [PMID: 36671549 PMCID: PMC9855881 DOI: 10.3390/biom13010164] [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: 12/21/2022] [Revised: 01/08/2023] [Accepted: 01/10/2023] [Indexed: 01/14/2023] Open
Abstract
Immuno-positron emission tomography (immunoPET) is a non-invasive in vivo imaging method based on tracking and quantifying radiolabeled monoclonal antibodies (mAbs) and other related molecules, such as antibody fragments, nanobodies, or affibodies. However, the success of immunoPET in neuroimaging is limited because intact antibodies cannot penetrate the blood-brain barrier (BBB). In neuro-oncology, immunoPET has been successfully applied to brain tumors because of the compromised BBB. Different strategies, such as changes in antibody properties, use of physiological mechanisms in the BBB, or induced changes to BBB permeability, have been developed to deliver antibodies to the brain. These approaches have recently started to be applied in preclinical central nervous system PET studies. Therefore, immunoPET could be a new approach for developing more specific PET probes directed to different brain targets.
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13
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Warden AS, Han C, Hansen E, Trescott S, Nguyen C, Kim R, Schafer D, Johnson A, Wright M, Ramirez G, Lopez-Sanchez M, Coufal NG. Tools for studying human microglia: In vitro and in vivo strategies. Brain Behav Immun 2023; 107:369-382. [PMID: 36336207 PMCID: PMC9810377 DOI: 10.1016/j.bbi.2022.10.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 09/11/2022] [Accepted: 10/13/2022] [Indexed: 11/06/2022] Open
Abstract
Microglia may only represent 10% of central nervous system (CNS) cells but they perform critical roles in development, homeostasis and neurological disease. Microglia are also environmentally regulated, quickly losing their transcriptomic and epigenetic signature after leaving the CNS. This facet of microglia biology is both fascinating and technically challenging influencing the study of the genetics and function of human microglia in a manner that recapitulates the CNS environment. In this review we provide a comprehensive overview of existing in vitro and in vivo methodology to study human microglia, such as immortalized cells lines, stem cell-derived microglia, cerebral organoids and xenotransplantation. Since there is currently no single method that completely recapitulates all hallmarks of human ex vivo adult homeostatic microglia, we also discuss the advantages and limitations of each existing model as a practical guide for researchers.
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Affiliation(s)
- Anna S Warden
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA; Sanford Consortium for Regenerative Medicine, La Jolla, CA 92037, USA; Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Claudia Han
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Emily Hansen
- Sanford Consortium for Regenerative Medicine, La Jolla, CA 92037, USA; Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Samantha Trescott
- Sanford Consortium for Regenerative Medicine, La Jolla, CA 92037, USA; Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Celina Nguyen
- Sanford Consortium for Regenerative Medicine, La Jolla, CA 92037, USA
| | - Roy Kim
- Sanford Consortium for Regenerative Medicine, La Jolla, CA 92037, USA; Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Danielle Schafer
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA; Sanford Consortium for Regenerative Medicine, La Jolla, CA 92037, USA
| | - Avalon Johnson
- Sanford Consortium for Regenerative Medicine, La Jolla, CA 92037, USA; Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Madison Wright
- Sanford Consortium for Regenerative Medicine, La Jolla, CA 92037, USA; Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Gabriela Ramirez
- Sanford Consortium for Regenerative Medicine, La Jolla, CA 92037, USA; Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Mark Lopez-Sanchez
- Sanford Consortium for Regenerative Medicine, La Jolla, CA 92037, USA; Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Nicole G Coufal
- Sanford Consortium for Regenerative Medicine, La Jolla, CA 92037, USA; Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA.
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14
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Boyle AJ, Murrell E, Tong J, Schifani C, Narvaez A, Wuest M, West F, Wuest F, Vasdev N. PET Imaging of Fructose Metabolism in a Rodent Model of Neuroinflammation with 6-[ 18F]fluoro-6-deoxy-D-fructose. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27238529. [PMID: 36500626 PMCID: PMC9736258 DOI: 10.3390/molecules27238529] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 11/28/2022] [Accepted: 11/30/2022] [Indexed: 12/12/2022]
Abstract
Fluorine-18 labeled 6-fluoro-6-deoxy-D-fructose (6-[18F]FDF) targets the fructose-preferred facilitative hexose transporter GLUT5, which is expressed predominantly in brain microglia and activated in response to inflammatory stimuli. We hypothesize that 6-[18F]FDF will specifically image microglia following neuroinflammatory insult. 6-[18F]FDF and, for comparison, [18F]FDG were evaluated in unilateral intra-striatal lipopolysaccharide (LPS)-injected male and female rats (50 µg/animal) by longitudinal dynamic PET imaging in vivo. In LPS-injected rats, increased accumulation of 6-[18F]FDF was observed at 48 h post-LPS injection, with plateaued uptake (60-120 min) that was significantly higher in the ipsilateral vs. contralateral striatum (0.985 ± 0.047 and 0.819 ± 0.033 SUV, respectively; p = 0.002, n = 4M/3F). The ipsilateral-contralateral difference in striatal 6-[18F]FDF uptake expressed as binding potential (BPSRTM) peaked at 48 h (0.19 ± 0.11) and was significantly decreased at one and two weeks. In contrast, increased [18F]FDG uptake in the ipsilateral striatum was highest at one week post-LPS injection (BPSRTM = 0.25 ± 0.06, n = 4M). Iba-1 and GFAP immunohistochemistry confirmed LPS-induced activation of microglia and astrocytes, respectively, in ipsilateral striatum. This proof-of-concept study revealed an early response of 6-[18F]FDF to neuroinflammatory stimuli in rat brain. 6-[18F]FDF represents a potential PET radiotracer for imaging microglial GLUT5 density in brain with applications in neuroinflammatory and neurodegenerative diseases.
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Affiliation(s)
- Amanda J. Boyle
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health, 250 College St., Toronto, ON M5T 1R8, Canada
- Department of Psychiatry, University of Toronto, 250 College St., Toronto, ON M5T 1R8, Canada
- Correspondence: (A.J.B.); (N.V.); Tel.: +1-416-535-8501 (ext. 30884) (A.J.B.); +1-416-535-8501 (ext. 30988) (N.V.)
| | - Emily Murrell
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health, 250 College St., Toronto, ON M5T 1R8, Canada
| | - Junchao Tong
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health, 250 College St., Toronto, ON M5T 1R8, Canada
| | - Christin Schifani
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health, 250 College St., Toronto, ON M5T 1R8, Canada
| | - Andrea Narvaez
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health, 250 College St., Toronto, ON M5T 1R8, Canada
| | - Melinda Wuest
- Department of Chemistry, University of Alberta, Edmonton, AB T6G 2N4, Canada
| | - Frederick West
- Department of Chemistry, University of Alberta, Edmonton, AB T6G 2N4, Canada
- Department of Oncology, University of Alberta, Edmonton, AB T6G 1Z2, Canada
| | - Frank Wuest
- Department of Chemistry, University of Alberta, Edmonton, AB T6G 2N4, Canada
- Department of Oncology, University of Alberta, Edmonton, AB T6G 1Z2, Canada
| | - Neil Vasdev
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health, 250 College St., Toronto, ON M5T 1R8, Canada
- Department of Psychiatry, University of Toronto, 250 College St., Toronto, ON M5T 1R8, Canada
- Correspondence: (A.J.B.); (N.V.); Tel.: +1-416-535-8501 (ext. 30884) (A.J.B.); +1-416-535-8501 (ext. 30988) (N.V.)
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15
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Ma BB, Montgomery AP, Chen B, Kassiou M, Danon JJ. Strategies for targeting the P2Y 12 receptor in the central nervous system. Bioorg Med Chem Lett 2022; 71:128837. [PMID: 35640763 DOI: 10.1016/j.bmcl.2022.128837] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 05/10/2022] [Accepted: 05/26/2022] [Indexed: 11/28/2022]
Abstract
The purinergic 2Y type 12 receptor (P2Y12R) is a well-known biological target for anti-thrombotic drugs due to its role in platelet aggregation and blood clotting. While the importance of the P2Y12R in the periphery has been known for decades, much less is known about its expression and roles in the central nervous system (CNS), where it is expressed exclusively on microglia - the first responders to brain insults and neurodegeneration. Several seminal studies have shown that P2Y12 is a robust, translatable biomarker for anti-inflammatory and neuroprotective microglial phenotypes in models of degenerative diseases such as multiple sclerosis and Alzheimer's disease. An enduring problem for studying this receptor in vivo, however, is the lack of selective, high-affinity small molecule ligands that can bypass the blood-brain barrier and accumulate in the CNS. In this Digest, we discuss previous attempts by researchers to target the P2Y12R in the CNS and opine on strategies that may be employed to design and assess the suitability of novel P2Y12 ligands for this purpose going forward.
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Affiliation(s)
- Ben B Ma
- School of Chemistry, The University of Sydney, Sydney, NSW 2006, Australia
| | | | - Biling Chen
- School of Chemistry, The University of Sydney, Sydney, NSW 2006, Australia
| | - Michael Kassiou
- School of Chemistry, The University of Sydney, Sydney, NSW 2006, Australia
| | - Jonathan J Danon
- School of Chemistry, The University of Sydney, Sydney, NSW 2006, Australia.
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16
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Prasuhn J, Kunert L, Brüggemann N. Neuroimaging Methods to Map In Vivo Changes of OXPHOS and Oxidative Stress in Neurodegenerative Disorders. Int J Mol Sci 2022; 23:ijms23137263. [PMID: 35806267 PMCID: PMC9266616 DOI: 10.3390/ijms23137263] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 06/24/2022] [Accepted: 06/25/2022] [Indexed: 12/11/2022] Open
Abstract
Mitochondrial dysfunction is a pathophysiological hallmark of most neurodegenerative diseases. Several clinical trials targeting mitochondrial dysfunction have been performed with conflicting results. Reliable biomarkers of mitochondrial dysfunction in vivo are thus needed to optimize future clinical trial designs. This narrative review highlights various neuroimaging methods to probe mitochondrial dysfunction. We provide a general overview of the current biological understanding of mitochondrial dysfunction in degenerative brain disorders and how distinct neuroimaging methods can be employed to map disease-related changes. The reviewed methodological spectrum includes positron emission tomography, magnetic resonance, magnetic resonance spectroscopy, and near-infrared spectroscopy imaging, and how these methods can be applied to study alterations in oxidative phosphorylation and oxidative stress. We highlight the advantages and shortcomings of the different neuroimaging methods and discuss the necessary steps to use these for future research. This review stresses the importance of neuroimaging methods to gain deepened insights into mitochondrial dysfunction in vivo, its role as a critical disease mechanism in neurodegenerative diseases, the applicability for patient stratification in interventional trials, and the quantification of individual treatment responses. The in vivo assessment of mitochondrial dysfunction is a crucial prerequisite for providing individualized treatments for neurodegenerative disorders.
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Affiliation(s)
- Jannik Prasuhn
- Institute of Neurogenetics, University of Lübeck, 23538 Lübeck, Germany; (J.P.); (L.K.)
- Department of Neurology, University Medical Center Schleswig Holstein, Campus Lübeck, 23538 Lübeck, Germany
- Center for Brain, Behavior and Metabolism, University of Lübeck, 23562 Lübeck, Germany
| | - Liesa Kunert
- Institute of Neurogenetics, University of Lübeck, 23538 Lübeck, Germany; (J.P.); (L.K.)
- Department of Neurology, University Medical Center Schleswig Holstein, Campus Lübeck, 23538 Lübeck, Germany
- Center for Brain, Behavior and Metabolism, University of Lübeck, 23562 Lübeck, Germany
| | - Norbert Brüggemann
- Institute of Neurogenetics, University of Lübeck, 23538 Lübeck, Germany; (J.P.); (L.K.)
- Department of Neurology, University Medical Center Schleswig Holstein, Campus Lübeck, 23538 Lübeck, Germany
- Center for Brain, Behavior and Metabolism, University of Lübeck, 23562 Lübeck, Germany
- Correspondence: ; Tel.: +49-451-500-43420; Fax: +49-451-500-43424
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17
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Nicotinic Acetylcholine Receptors and Microglia as Therapeutic and Imaging Targets in Alzheimer's Disease. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27092780. [PMID: 35566132 PMCID: PMC9102429 DOI: 10.3390/molecules27092780] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 04/21/2022] [Accepted: 04/25/2022] [Indexed: 12/12/2022]
Abstract
Amyloid-β (Aβ) accumulation and tauopathy are considered the pathological hallmarks of Alzheimer’s disease (AD), but attenuation in choline signaling, including decreased nicotinic acetylcholine receptors (nAChRs), is evident in the early phase of AD. Currently, there are no drugs that can suppress the progression of AD due to a limited understanding of AD pathophysiology. For this, diagnostic methods that can assess disease progression non-invasively before the onset of AD symptoms are essential, and it would be valuable to incorporate the concept of neurotheranostics, which simultaneously enables diagnosis and treatment. The neuroprotective pathways activated by nAChRs are attractive targets as these receptors may regulate microglial-mediated neuroinflammation. Microglia exhibit both pro- and anti-inflammatory functions that could be modulated to mitigate AD pathogenesis. Currently, single-cell analysis is identifying microglial subpopulations that may have specific functions in different stages of AD pathologies. Thus, the ability to image nAChRs and microglia in AD according to the stage of the disease in the living brain may lead to the development of new diagnostic and therapeutic methods. In this review, we summarize and discuss the recent findings on the nAChRs and microglia, as well as their methods for live imaging in the context of diagnosis, prophylaxis, and therapy for AD.
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18
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Chuang JY. Stressor-Specific Microbiota Intervention. Front Nutr 2022; 9:870665. [PMID: 35520283 PMCID: PMC9063858 DOI: 10.3389/fnut.2022.870665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Accepted: 03/22/2022] [Indexed: 11/13/2022] Open
Abstract
To date, mental disorders are diagnosed and treated by the subjective judgment of psychiatrists based on diagnostic criteria and treatment guidelines, respectively. Mental disorders are heterogeneous illnesses with a substantial treatment-refractory rate. Thus, there is a great need for novel treatment approaches. This article proposes a treatment approach centered on the concept of the gut–brain axis. There is mounting evidence indicating an association between stressors, microbiota, microglia, and mental disorders. Stressors might facilitate dysbiosis, inflammation, and the occurrence of mental disorders. This novel treatment approach is based on the idea that stressor types instead of the heterogeneous psychiatric diagnosis might be closer to the neurobiological underpinnings of mental disorders. First of all, patients with treatment-resistant mental disorders will be asked to describe their major stressors. Then, clinicians will calculate the total threat score and the total deprivation score. Subsequently, treatment tailored to the major stressor type will be administered to restore a healthy gut microbiome. Presumably, treatment will be aimed at increasing microbiota diversity in those who mainly have deprivation stressors and boosting Actinobacteria in those who have mainly threat stressors. Large-scale clinical trials are warranted to test this hypothetical approach.
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Affiliation(s)
- Jie-Yu Chuang
- Department of Psychiatry, Cardinal Tien Hospital, New Taipei City, Taiwan
- School of Medicine, College of Medicine, Fu Jen Catholic University, New Taipei City, Taiwan
- *Correspondence: Jie-Yu Chuang
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19
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Zhang J, Li Z, Fan M, Jin W. Lipoxins in the Nervous System: Brighter Prospects for Neuroprotection. Front Pharmacol 2022; 13:781889. [PMID: 35153778 PMCID: PMC8826722 DOI: 10.3389/fphar.2022.781889] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Accepted: 01/07/2022] [Indexed: 12/28/2022] Open
Abstract
Lipoxins (LXs) are generated from arachidonic acid and are involved in the resolution of inflammation and confer protection in a variety of pathological processes. In the nervous system, LXs exert an array of protective effects against neurological diseases, including ischemic or hemorrhagic stroke, neonatal hypoxia-ischemia encephalopathy, brain and spinal cord injury, Alzheimer's disease, multiple sclerosis, and neuropathic pain. Lipoxin administration is a potential therapeutic strategy in neurological diseases due to its notable efficiency and unique superiority regarding safety. Here, we provide an overview of LXs in terms of their synthesis, signaling pathways and neuroprotective evidence. Overall, we believe that, along with advances in lipoxin-related drug design, LXs will bring brighter prospects for neuroprotection.
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Affiliation(s)
- Jiayu Zhang
- Graduate School of Hebei Medical University, Shijiazhuang, China.,Department of Neurology, Hebei General Hospital, Shijiazhuang, China
| | - Zhe Li
- Department of Neurology, Hebei General Hospital, Shijiazhuang, China
| | - Mingyue Fan
- Department of Neurology, Hebei General Hospital, Shijiazhuang, China
| | - Wei Jin
- Department of Neurology, Hebei General Hospital, Shijiazhuang, China
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20
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Golde TE. Disease-Modifying Therapies for Alzheimer's Disease: More Questions than Answers. Neurotherapeutics 2022; 19:209-227. [PMID: 35229269 PMCID: PMC8885119 DOI: 10.1007/s13311-022-01201-2] [Citation(s) in RCA: 36] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/09/2022] [Indexed: 12/17/2022] Open
Abstract
Scientific advances over the last four decades have steadily infused the Alzheimer's disease (AD) field with great optimism that therapies targeting Aβ, amyloid, tau, and innate immune activation states in the brain would provide disease modification. Unfortunately, this optimistic scenario has not yet played out. Though a recent approval of the anti-Aβ aggregate binding antibody, Aduhelm (aducanumab), as a "disease-modifying therapy for AD" is viewed by some as a breakthrough, many remain unconvinced by the data underlying this approval. Collectively, we have not succeeded in changing AD from a largely untreatable, inevitable, and incurable disease to a treatable, preventable, and curable one. Here, I will review the major foci of the AD "disease-modifying" therapeutic pipeline and some of the "open questions" that remain in terms of these therapeutic approaches. I will conclude the review by discussing how we, as a field, might adjust our approach, learning from our past failures to ensure future success.
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Affiliation(s)
- Todd E Golde
- Departments of Neuroscience and Neurology, Center for Translational Research in Neurodegenerative Disease, Evelyn F. and William L. McKnight Brain Institute, Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL, USA.
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21
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van der Wildt B, Janssen B, Pekošak A, Stéen EJL, Schuit RC, Kooijman EJM, Beaino W, Vugts DJ, Windhorst AD. Novel Thienopyrimidine-Based PET Tracers for P2Y 12 Receptor Imaging in the Brain. ACS Chem Neurosci 2021; 12:4465-4474. [PMID: 34757711 PMCID: PMC8640995 DOI: 10.1021/acschemneuro.1c00641] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
![]()
The P2Y12 receptor (P2Y12R) is uniquely expressed
on microglia in the brain, and its expression level directly depends
on the microglial activation state. Therefore, P2Y12R provides
a promising imaging marker for distinguishing the pro- and anti-inflammatory
microglial phenotypes, both of which play crucial roles in neuroinflammatory
diseases. In this study, three P2Y12R antagonists were
selected from the literature, radiolabeled with carbon-11 or fluorine-18,
and evaluated in healthy Wistar rats. Brain imaging was performed
with and without blocking of efflux transporters P-glycoprotein and breast cancer resistance protein using tariquidar.
Low brain uptake in healthy rats was observed for all tracers at baseline
conditions, whereas blocking of efflux transporters resulted in a
strong (6–7 fold) increase in brain uptake for both of them.
Binding of the most promising tracer, [18F]3, was further evaluated by in vitro autoradiography on rat brain
sections, ex vivo metabolite studies, and in vivo P2Y12R blocking studies. In vitro binding of [18F]3 on rat brain sections indicated high P2Y12R targeting
with approximately 70% selective and specific binding. At 60 min post-injection,
over 95% of radioactivity in the brain accounted for an intact tracer.
In blood plasma, still 40% intact tracer was found, and formed metabolites
did not enter the brain. A moderate P2Y12R blocking effect
was observed in vivo by positron emission tomography (PET) imaging
with [18F]3 (p = 0.04). To
conclude, three potential P2Y12R PET tracers were obtained
and analyzed for P2Y12R targeting in the brain. Unfortunately,
the brain uptake appeared low. Future work will focus on the design
of P2Y12R inhibitors with improved physicochemical characteristics
to reduce efflux transport and increase brain penetration.
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Affiliation(s)
- Berend van der Wildt
- Department of Radiology & Nuclear Medicine, Neuroscience Amsterdam, Amsterdam UMC, Vrije Universiteit Amsterdam, De Boelelaan 1117, 1081HV Amsterdam, The Netherlands
| | - Bieneke Janssen
- Department of Radiology & Nuclear Medicine, Neuroscience Amsterdam, Amsterdam UMC, Vrije Universiteit Amsterdam, De Boelelaan 1117, 1081HV Amsterdam, The Netherlands
| | - Aleksandra Pekošak
- Department of Radiology & Nuclear Medicine, Neuroscience Amsterdam, Amsterdam UMC, Vrije Universiteit Amsterdam, De Boelelaan 1117, 1081HV Amsterdam, The Netherlands
| | - E. Johanna L. Stéen
- Department of Radiology & Nuclear Medicine, Neuroscience Amsterdam, Amsterdam UMC, Vrije Universiteit Amsterdam, De Boelelaan 1117, 1081HV Amsterdam, The Netherlands
| | - Robert C. Schuit
- Department of Radiology & Nuclear Medicine, Neuroscience Amsterdam, Amsterdam UMC, Vrije Universiteit Amsterdam, De Boelelaan 1117, 1081HV Amsterdam, The Netherlands
| | - Esther J. M. Kooijman
- Department of Radiology & Nuclear Medicine, Neuroscience Amsterdam, Amsterdam UMC, Vrije Universiteit Amsterdam, De Boelelaan 1117, 1081HV Amsterdam, The Netherlands
| | - Wissam Beaino
- Department of Radiology & Nuclear Medicine, Neuroscience Amsterdam, Amsterdam UMC, Vrije Universiteit Amsterdam, De Boelelaan 1117, 1081HV Amsterdam, The Netherlands
| | - Danielle J. Vugts
- Department of Radiology & Nuclear Medicine, Neuroscience Amsterdam, Amsterdam UMC, Vrije Universiteit Amsterdam, De Boelelaan 1117, 1081HV Amsterdam, The Netherlands
| | - Albert D. Windhorst
- Department of Radiology & Nuclear Medicine, Neuroscience Amsterdam, Amsterdam UMC, Vrije Universiteit Amsterdam, De Boelelaan 1117, 1081HV Amsterdam, The Netherlands
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22
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Abstract
Innate and adaptive immune responses in the central nervous system (CNS) play critical roles in the pathogenesis of neurological diseases. In the first of a two-part special issue, leading researchers discuss how imaging modalities are used to monitor immune responses in several neurodegenerative diseases and glioblastoma and brain metastases. While comparative studies in humans between imaging and pathology are biased towards the end stage of disease, animal models can inform regarding how immune responses change with disease progression and as a result of treatment regimens. Magnetic resonance imaging (MRI) and positron emission tomography (PET) are frequently used to image disease progression, and the articles indicate how one or more of these modalities have been applied to specific neuroimmune diseases. In addition, advanced microscopical imaging using two-dimensional photon microscopy and in vitro live cell imaging have also been applied to animal models. In this special issue (Parts 1 and 2), as well as the imaging modalities mentioned, several articles discuss biomarkers of disease and microscopical studies that have enabled characterization of immune responses. Future developments of imaging modalities should enable tracking of specific subsets of immune cells during disease allowing longitudinal monitoring of immune responses. These new approaches will be critical to more effectively monitor and thus target specific cell subsets for therapeutic interventions which may be applicable to a range of neurological diseases.
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Affiliation(s)
- Sandra Amor
- Department of PathologyAmsterdam UMC Location VUmcAmsterdamthe Netherlands
- Department of Neuroscience and TraumaBlizard InstituteBarts and the London School of Medicine and DentistryQueen Mary University of LondonLondonUK
| | - Erik Nutma
- Department of PathologyAmsterdam UMC Location VUmcAmsterdamthe Netherlands
| | - David Owen
- Department of Brain SciencesImperial College LondonLondonUK
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Ni R. Positron Emission Tomography in Animal Models of Alzheimer's Disease Amyloidosis: Translational Implications. Pharmaceuticals (Basel) 2021; 14:1179. [PMID: 34832961 PMCID: PMC8623863 DOI: 10.3390/ph14111179] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 11/13/2021] [Accepted: 11/15/2021] [Indexed: 12/30/2022] Open
Abstract
Animal models of Alzheimer's disease amyloidosis that recapitulate cerebral amyloid-beta pathology have been widely used in preclinical research and have greatly enabled the mechanistic understanding of Alzheimer's disease and the development of therapeutics. Comprehensive deep phenotyping of the pathophysiological and biochemical features in these animal models is essential. Recent advances in positron emission tomography have allowed the non-invasive visualization of the alterations in the brain of animal models and in patients with Alzheimer's disease. These tools have facilitated our understanding of disease mechanisms and provided longitudinal monitoring of treatment effects in animal models of Alzheimer's disease amyloidosis. In this review, we focus on recent positron emission tomography studies of cerebral amyloid-beta accumulation, hypoglucose metabolism, synaptic and neurotransmitter receptor deficits (cholinergic and glutamatergic system), blood-brain barrier impairment, and neuroinflammation (microgliosis and astrocytosis) in animal models of Alzheimer's disease amyloidosis. We further propose the emerging targets and tracers for reflecting the pathophysiological changes and discuss outstanding challenges in disease animal models and future outlook in the on-chip characterization of imaging biomarkers towards clinical translation.
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Affiliation(s)
- Ruiqing Ni
- Institute for Biomedical Engineering, ETH & University of Zurich, 8093 Zurich, Switzerland;
- Institute for Regenerative Medicine, University of Zurich, 8952 Zurich, Switzerland
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Preliminary Assessment of the Anti-inflammatory Activity of New Structural Honokiol Analogs with a 4'- O-(2-Fluoroethyl) Moiety and the Potential of Their 18F-Labeled Derivatives for Neuroinflammation Imaging. Molecules 2021; 26:molecules26216630. [PMID: 34771039 PMCID: PMC8587714 DOI: 10.3390/molecules26216630] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 10/24/2021] [Accepted: 10/28/2021] [Indexed: 01/31/2023] Open
Abstract
Neolignans honokiol and 4′-O-methylhonokiol (MH) and their derivatives have pronounced anti-inflammatory activity, as evidenced by numerous pharmacological studies. Literature data suggested that cyclooxygenase type 2 (COX-2) may be a target for these compounds in vitro and in vivo. Recent studies of [11C]MPbP (4′-[11C]methoxy-5-propyl-1,1′-biphenyl-2-ol) biodistribution in LPS (lipopolysaccharide)-treated rats have confirmed the high potential of MH derivatives for imaging neuroinflammation. Here, we report the synthesis of four structural analogs of honokiol, of which 4′-(2-fluoroethoxy)-2-hydroxy-5-propyl-1, 1′-biphenyl (F-IV) was selected for labeling with fluorine-18 (T1/2 = 109.8 min) due to its high anti-inflammatory activity confirmed by enzyme immunoassays (EIA) and neuromorphological studies. The high inhibitory potency of F-IV to COX-2 and its moderate lipophilicity and chemical stability are favorable factors for the preliminary evaluation of the radioligand [18F]F-IV in a rodent model of neuroinflammation. [18F]F-IV was prepared with good radiochemical yield and high molar activity and radiochemical purity by 18F-fluoroethylation of the precursor with Boc-protecting group (15) with [18F]2-fluoro-1-bromoethane ([18F]FEB). Ex vivo biodistribution studies revealed a small to moderate increase in radioligand uptake in the brain and peripheral organs of LPS-induced rats compared to control animals. Pretreatment with celecoxib resulted in significant blocking of radioactivity uptake in the brain (pons and medulla), heart, lungs, and kidneys, indicating that [18F]F-IV is likely to specifically bind to COX-2 in a rat model of neuroinflammation. However, in comparison with [11C]MPbP, the new radioligand showed decreased brain uptake in LPS rats and high retention in the blood pool, which apparently could be explained by its high plasma protein binding. We believe that the structure of [18F]F-IV can be optimized by replacing the substituents in the biphenyl core to eliminate these disadvantages and develop new radioligands for imaging activated microglia.
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Ferguson A, Milling S. Do peripheral protein oligomers in neurodegenerative diseases shape T cell responses beyond the brain? Immunology 2021; 164:209-210. [PMID: 34523728 DOI: 10.1111/imm.13414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Neurodegenerative diseases place a devastating burden on affected individuals and their families, and new treatments are desperately needed for these common immune-mediated inflammatory conditions. While large aggregates of abnormal proteins in the brain cause significant damage, it is becoming clear that smaller soluble protein aggregates can also contribute to disease, by both direct and indirect mechanisms. These soluble protein oligomers can be found in patients' serum. Here, we describe recent research that identifies effects of model oligomer molecules on peripheral blood T cells, therefore providing an additional mechanism by which neurodegeneration may be worsened through amplification of peripheral adaptive immune responses.
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Affiliation(s)
- Annabelle Ferguson
- Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, UK
| | - Simon Milling
- Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, UK
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