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Aguado C, Badesso S, Martínez-Hernández J, Martín-Belmonte A, Alfaro-Ruiz R, Fernández M, Moreno-Martínez AE, Cuadrado-Tejedor M, García-Osta A, Luján R. Resilience to structural and molecular changes in excitatory synapses in the hippocampus contributes to cognitive function recovery in Tg2576 mice. Neural Regen Res 2024; 19:2068-2074. [PMID: 38227537 DOI: 10.4103/1673-5374.390963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2023] [Accepted: 11/18/2023] [Indexed: 01/17/2024] Open
Abstract
JOURNAL/nrgr/04.03/01300535-202409000-00040/figure1/v/2024-01-16T170235Z/r/image-tiff Plaques of amyloid-β (Aβ) and neurofibrillary tangles are the main pathological characteristics of Alzheimer's disease (AD). However, some older adult people with AD pathological hallmarks can retain cognitive function. Unraveling the factors that lead to this cognitive resilience to AD offers promising prospects for identifying new therapeutic targets. Our hypothesis focuses on the contribution of resilience to changes in excitatory synapses at the structural and molecular levels, which may underlie healthy cognitive performance in aged AD animals. Utilizing the Morris Water Maze test, we selected resilient (asymptomatic) and cognitively impaired aged Tg2576 mice. While the enzyme-linked immunosorbent assay showed similar levels of Aβ42 in both experimental groups, western blot analysis revealed differences in tau pathology in the pre-synaptic supernatant fraction. To further investigate the density of synapses in the hippocampus of 16-18 month-old Tg2576 mice, we employed stereological and electron microscopic methods. Our findings indicated a decrease in the density of excitatory synapses in the stratum radiatum of the hippocampal CA1 in cognitively impaired Tg2576 mice compared with age-matched resilient Tg2576 and non-transgenic controls. Intriguingly, through quantitative immunoelectron microscopy in the hippocampus of impaired and resilient Tg2576 transgenic AD mice, we uncovered differences in the subcellular localization of glutamate receptors. Specifically, the density of GluA1, GluA2/3, and mGlu5 in spines and dendritic shafts of CA1 pyramidal cells in impaired Tg2576 mice was significantly reduced compared with age-matched resilient Tg2576 and non-transgenic controls. Notably, the density of GluA2/3 in resilient Tg2576 mice was significantly increased in spines but not in dendritic shafts compared with impaired Tg2576 and non-transgenic mice. These subcellular findings strongly support the hypothesis that dendritic spine plasticity and synaptic machinery in the hippocampus play crucial roles in the mechanisms of cognitive resilience in Tg2576 mice.
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Affiliation(s)
- Carolina Aguado
- Synaptic Structure Laboratory, Instituto de Investigación en Discapacidades Neurológicas (IDINE), Department of Medical Sciences, Facultad de Medicina, Universidad de Castilla-La Mancha, Campus Biosanitario, Albacete, Spain
| | - Sara Badesso
- Gene Therapy for Neurological Disease Program, Center for Applied Medical Research (CIMA), University of Navarra, Instituto de Investigación Sanitaria de Navarra (IdiSNA), Pamplona, Spain
| | - José Martínez-Hernández
- Synaptic Structure Laboratory, Instituto de Investigación en Discapacidades Neurológicas (IDINE), Department of Medical Sciences, Facultad de Medicina, Universidad de Castilla-La Mancha, Campus Biosanitario, Albacete, Spain
| | - Alejandro Martín-Belmonte
- Pharmacology Unit, Department of Pathology and Experimental Therapeutics, Faculty of Medicine and Health Sciences, Institute of Neurosciences, University of Barcelona, Barcelona, Spain
- Neuropharmacology and Pain Group, Neuroscience Program, Institut d'Investigació Biomèdica de Bellvitge, IDIBELL, L'Hospitalet de Llobregat, Spain
| | - Rocío Alfaro-Ruiz
- Synaptic Structure Laboratory, Instituto de Investigación en Discapacidades Neurológicas (IDINE), Department of Medical Sciences, Facultad de Medicina, Universidad de Castilla-La Mancha, Campus Biosanitario, Albacete, Spain
| | - Miriam Fernández
- Synaptic Structure Laboratory, Instituto de Investigación en Discapacidades Neurológicas (IDINE), Department of Medical Sciences, Facultad de Medicina, Universidad de Castilla-La Mancha, Campus Biosanitario, Albacete, Spain
| | - Ana Esther Moreno-Martínez
- Synaptic Structure Laboratory, Instituto de Investigación en Discapacidades Neurológicas (IDINE), Department of Medical Sciences, Facultad de Medicina, Universidad de Castilla-La Mancha, Campus Biosanitario, Albacete, Spain
| | - Mar Cuadrado-Tejedor
- Gene Therapy for Neurological Disease Program, Center for Applied Medical Research (CIMA), University of Navarra, Instituto de Investigación Sanitaria de Navarra (IdiSNA), Pamplona, Spain
- Department of Pathology, Anatomy and Physiology, School of Medicine, University of Navarra, Pamplona, Spain
| | - Ana García-Osta
- Gene Therapy for Neurological Disease Program, Center for Applied Medical Research (CIMA), University of Navarra, Instituto de Investigación Sanitaria de Navarra (IdiSNA), Pamplona, Spain
| | - Rafael Luján
- Synaptic Structure Laboratory, Instituto de Investigación en Discapacidades Neurológicas (IDINE), Department of Medical Sciences, Facultad de Medicina, Universidad de Castilla-La Mancha, Campus Biosanitario, Albacete, Spain
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Li J, Huang Q, Qi N, He K, Li S, Huang L, Pan F, Ren S, Hua F, Huang Y, Guan Y, Guo Q, Zhao J, Xie F. The associations between synaptic density and "A/T/N" biomarkers in Alzheimer's disease: An 18F-SynVesT-1 PET/MR study. J Cereb Blood Flow Metab 2024; 44:1199-1207. [PMID: 38295871 PMCID: PMC11179616 DOI: 10.1177/0271678x241230733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 12/08/2023] [Accepted: 12/26/2023] [Indexed: 06/13/2024]
Abstract
A newly developed SV2A radiotracer, 18F-SynVesT-1, was used in this study to investigate synaptic density and its association with Alzheimer's disease (AD) "A/T/N" biomarkers. The study included a cohort of 97 subjects, consisting of 64 patients with cognitive impairment (CI) and 33 individuals with normal cognition (CU). All subjects underwent 18F-SynVesT-1 PET/MR and 18F-florbetapir PET/CT scans. Additionally, a subgroup of individuals also underwent 18F-MK-6240, 18F-FDG PET/CT, plasma Aβ42/Aβ40 and p-tau181 tests. The differences in synaptic density between the groups and the correlations between synaptic density and AD "A/T/N" biomarkers were analyzed. The results showed that compared to the CU group, the CI with Aβ+ (CI+) group exhibited the most pronounced synapse loss in the hippocampus, with some loss also observed in the neocortex. Furthermore, synaptic density in the hippocampus and parahippocampal gyrus showed associations with AD biomarkers detected by both imaging and plasma tests in the CI group. The associations between synaptic density and FDG uptake and hippocampal volume were also observed in the CI+ group. In conclusion, the study demonstrated significant synaptic density loss, as measured by the promising tracer 18F-SynVesT-1, and its close correlation with "A/T/N" biomarkers in patients with both Alzheimer's clinical syndrome and pathological changes.
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Affiliation(s)
- Junpeng Li
- Department of Nuclear Medicine & PET Center, Huashan Hospital, Fudan University, Shanghai, China
- Department of Nuclear Medicine, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Qi Huang
- Department of Nuclear Medicine & PET Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Na Qi
- Department of Nuclear Medicine, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China
| | - Kun He
- Department of Nuclear Medicine & PET Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Songye Li
- PET Center, Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Lin Huang
- Department of Gerontology, Shanghai Jiaotong University Affiliated Sixth People’s Hospital, Shanghai, China
| | - Fengfeng Pan
- Department of Gerontology, Shanghai Jiaotong University Affiliated Sixth People’s Hospital, Shanghai, China
| | - Shuhua Ren
- Department of Nuclear Medicine & PET Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Fengchun Hua
- Department of Nuclear Medicine, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Yiyun Huang
- PET Center, Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Yihui Guan
- Department of Nuclear Medicine & PET Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Qihao Guo
- Department of Gerontology, Shanghai Jiaotong University Affiliated Sixth People’s Hospital, Shanghai, China
| | - Jun Zhao
- Department of Nuclear Medicine, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China
| | - Fang Xie
- Department of Nuclear Medicine & PET Center, Huashan Hospital, Fudan University, Shanghai, China
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Wang J, Huang Q, He K, Li J, Guo T, Yang Y, Lin Z, Li S, Vanderlinden G, Huang Y, Van Laere K, Guan Y, Guo Q, Ni R, Li B, Xie F. Presynaptic density determined by SV2A PET is closely associated with postsynaptic metabotropic glutamate receptor 5 availability and independent of amyloid pathology in early cognitive impairment. Alzheimers Dement 2024; 20:3876-3888. [PMID: 38634334 PMCID: PMC11180932 DOI: 10.1002/alz.13817] [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: 11/27/2023] [Revised: 02/28/2024] [Accepted: 03/06/2024] [Indexed: 04/19/2024]
Abstract
INTRODUCTION Metabotropic glutamate receptor 5 (mGluR5) is involved in regulating integrative brain function and synaptic transmission. Aberrant mGluR5 signaling and relevant synaptic failure play a key role in the pathophysiological mechanism of Alzheimer's disease (AD). METHODS Ten cognitively impaired (CI) individuals and 10 healthy controls (HCs) underwent [18F]SynVesT-1 and [18F]PSS232 positron emission tomography (PET)/magnetic resonance to assess synaptic density and mGluR5 availability. The associations between mGluR5 availability and synaptic density were examined. A mediation analysis was performed to investigate the possible mediating effects of mGluR5 availability and synaptic loss on the relationship between amyloid deposition and cognition. RESULTS CI patients exhibited lower mGluR5 availability and synaptic density in the medial temporal lobe than HCs. Regional synaptic density was closely associated with regional mGluR5 availability. mGluR5 availability and synaptic loss partially mediated the relationship between amyloid deposition and cognition. CONCLUSIONS Reductions in mGluR5 availability and synaptic density exhibit similar spatial patterns in AD and are closely linked. HIGHLIGHTS Cognitively impaired patients exhibited lower mGluR5 availability and synaptic density in the medial temporal lobe than HCs. Reductions in mGluR5 availability and synaptic density exhibit similar spatial patterns in AD. Regional synaptic density was closely associated with regional mGluR5 availability. mGluR5 availability and synaptic loss partially mediated the relationship between amyloid deposition and global cognition. With further research, modulating mGluR5 availability might be a potential therapeutic strategy for improving synaptic function in AD.
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Affiliation(s)
- Jie Wang
- Department of Nuclear Medicine & PET CenterHuashan Hospital, Fudan UniversityShanghaiChina
| | - Qi Huang
- Department of Nuclear Medicine & PET CenterHuashan Hospital, Fudan UniversityShanghaiChina
| | - Kun He
- Department of Nuclear Medicine & PET CenterHuashan Hospital, Fudan UniversityShanghaiChina
| | - Junpeng Li
- Department of Nuclear Medicine & PET CenterHuashan Hospital, Fudan UniversityShanghaiChina
| | - Tengfei Guo
- Institute of Biomedical Engineering, Shenzhen Bay LaboratoryShenzhenChina
| | - Yang Yang
- Beijing United Imaging Research Institute of Intelligent ImagingBeijingChina
| | - Zengping Lin
- Central Research Institute, United Imaging Healthcare Group Co., LtdShanghaiChina
| | - Songye Li
- Department of Radiology and Biomedical ImagingPET CenterYale University School of MedicineNew HavenConnecticutUSA
| | - Greet Vanderlinden
- Department of Imaging and PathologyNuclear Medicine and Molecular Imaging, KU LeuvenLeuvenBelgium
| | - Yiyun Huang
- Department of Radiology and Biomedical ImagingPET CenterYale University School of MedicineNew HavenConnecticutUSA
| | - Koen Van Laere
- Department of Imaging and PathologyNuclear Medicine and Molecular Imaging, KU LeuvenLeuvenBelgium
| | - Yihui Guan
- Department of Nuclear Medicine & PET CenterHuashan Hospital, Fudan UniversityShanghaiChina
| | - Qihao Guo
- Department of GerontologyShanghai Jiao Tong University Affiliated Sixth People's HospitalShanghaiChina
| | - Ruiqing Ni
- Institute for Biomedical Engineering, University of Zurich & ETH ZurichZurichSwitzerland
- Institute for Regenerative MedicineUniversity of ZurichZurichSwitzerland
| | - Binying Li
- Department of Neurology and Institute of NeurologyRuijin Hospital, Shanghai Jiao Tong University School of MedicineShanghaiChina
| | - Fang Xie
- Department of Nuclear Medicine & PET CenterHuashan Hospital, Fudan UniversityShanghaiChina
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Fudan UniversityShanghaiChina
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Zhang J, Chen H, Wang J, Huang Q, Xu X, Wang W, Xu W, Guan Y, Liu J, Wardlaw JM, Deng Y, Xie F, Li B. Linking white matter hyperintensities to regional cortical thinning, amyloid deposition, and synaptic density loss in Alzheimer's disease. Alzheimers Dement 2024; 20:3931-3942. [PMID: 38648354 PMCID: PMC11180938 DOI: 10.1002/alz.13845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2023] [Revised: 02/16/2024] [Accepted: 03/21/2024] [Indexed: 04/25/2024]
Abstract
INTRODUCTION We investigated the association between white matter hyperintensities (WMH) and regional cortical thickness, amyloid and tau deposition, and synaptic density in the WMH-connected cortex using multimodal images. METHODS We included 107 participants (59 with Alzheimer's disease [AD]; 27 with mild cognitive impairment; 21 cognitively normal controls) with amyloid beta (Aβ) positivity on amyloid positron emission tomography (PET). The cortex connected to WMH was identified using probabilistic tractography. RESULTS We found that WMH connected to the cortex with more severe regional degeneration as measured by cortical thickness, Aβ and tau deposition, and synaptic vesicle glycoprotein 2 A (SV2A) density using 18F-SynVesT-1 PET. In addition, higher ratios of Aβ in the deep WMH-connected versus WMH-unconnected cortex were significantly related to lower cognitive scores. Last, the cortical thickness of WMH-connected cortex reduced more than WMH-unconnected cortex over 12 months. DISCUSSION Our results suggest that WMH may be associated with AD-intrinsic processes of degeneration, in addition to vascular mechanisms. HIGHLIGHTS We studied white matter hyperintensities (WMHs) and WMH-connected cortical changes. WMHs are associated with more severe regional cortical degeneration. Findings suggest WMHs may be associated with Alzheimer's disease-intrinsic processes of degeneration.
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Affiliation(s)
- Junfang Zhang
- Department of Neurology & Institute of NeurologyRuijin Hospital affiliated with Shanghai Jiao Tong University School of MedicineShanghaiChina
- Clinical Neuroscience CenterRuijin Hospital LuWan BranchShanghai Jiao Tong University School of MedicineShanghaiChina
| | - Haijuan Chen
- Department of Neurology & Institute of NeurologyRuijin Hospital affiliated with Shanghai Jiao Tong University School of MedicineShanghaiChina
- Clinical Neuroscience CenterRuijin Hospital LuWan BranchShanghai Jiao Tong University School of MedicineShanghaiChina
| | - Jie Wang
- PET CenterHuashan HospitalFudan UniversityShanghaiChina
| | - Qi Huang
- PET CenterHuashan HospitalFudan UniversityShanghaiChina
| | - Xiaomeng Xu
- Department of Neurology & Institute of NeurologyRuijin Hospital affiliated with Shanghai Jiao Tong University School of MedicineShanghaiChina
| | - Wenjing Wang
- Department of Neurology & Institute of NeurologyRuijin Hospital affiliated with Shanghai Jiao Tong University School of MedicineShanghaiChina
| | - Wei Xu
- Department of Neurology & Institute of NeurologyRuijin Hospital affiliated with Shanghai Jiao Tong University School of MedicineShanghaiChina
| | - Yihui Guan
- PET CenterHuashan HospitalFudan UniversityShanghaiChina
| | - Jun Liu
- Department of Neurology & Institute of NeurologyRuijin Hospital affiliated with Shanghai Jiao Tong University School of MedicineShanghaiChina
| | - Joanna M Wardlaw
- Centre for Clinical Brain SciencesUniversity of EdinburghEdinburghUK
- UK Dementia Research InstituteUniversity of EdinburghEdinburghUK
| | - Yulei Deng
- Department of Neurology & Institute of NeurologyRuijin Hospital affiliated with Shanghai Jiao Tong University School of MedicineShanghaiChina
- Clinical Neuroscience CenterRuijin Hospital LuWan BranchShanghai Jiao Tong University School of MedicineShanghaiChina
| | - Fang Xie
- PET CenterHuashan HospitalFudan UniversityShanghaiChina
| | - Binyin Li
- Department of Neurology & Institute of NeurologyRuijin Hospital affiliated with Shanghai Jiao Tong University School of MedicineShanghaiChina
- Clinical Neuroscience CenterRuijin Hospital LuWan BranchShanghai Jiao Tong University School of MedicineShanghaiChina
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Li H, Fan X, Li K, Zhang C, Jia X. Increased anterior insula connectivity associated with cognitive maintenance in amnestic mild cognitive impairment: a longitudinal study. Brain Imaging Behav 2024:10.1007/s11682-024-00899-2. [PMID: 38782876 DOI: 10.1007/s11682-024-00899-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/16/2024] [Indexed: 05/25/2024]
Abstract
The insula, a crucial hub of the human brain network, can be divided into anterior and posterior regions. Previous studies have reported that different insula subregions play various roles in amnestic mild cognitive impairment (aMCI). However, the longitudinal changes in the functional connectivity (FC) of each insula subregion in aMCI patients over time remain unclear. Twenty aMCI patients and 20 healthy controls (HCs) were recruited and underwent resting-state functional magnetic resonance imaging (fMRI) scans and neuropsychological assessments at baseline and at the 15-month follow-up. FMRI data were preprocessed using SPM 12 and the CONN toolbox. Two-way analysis of covariance was used to compare longitudinal changes in the FC of each insula subregion with covariates including sex, age, education, follow-up interval, volume of gray matter, and global correlation (GCOR). Pearson's correlation was used to evaluate the relationship between insula subregional FC and neuropsychological performance in aMCI patients. In aMCI patients, the right anterior insula exhibited significantly increased FC with the left anterior cingulate cortex, whereas the left posterior insula exhibited decreased FC with the right precuneus compared with HCs. Furthermore, FC between the right anterior insula and left anterior cingulate cortex was significantly correlated with global cognition at follow-up. The current findings revealed different functional alterations in the insula subregions and provided new insights into the neurodegenerative process in aMCI patients.
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Affiliation(s)
- Hui Li
- Department of Radiology, Beijing Chaoyang Hospital, Capital Medical University, No. 8, Gongti South Road, Chaoyang District, Beijing, 100020, China
| | - Xiang Fan
- Department of Medical Imaging, Peking University Shenzhen Hospital, Shenzhen, 518036, China
| | - Kuncheng Li
- Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing, 10053, China
| | - Chen Zhang
- MR Research Collaboration, Siemens Healthineers, Beijing, 100102, China
| | - Xiuqin Jia
- Department of Radiology, Beijing Chaoyang Hospital, Capital Medical University, No. 8, Gongti South Road, Chaoyang District, Beijing, 100020, China.
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He K, Li B, Wang J, Wang Y, You Z, Chen X, Chen H, Li J, Huang Q, Guo Q, Huang YH, Guan Y, Chen K, Zhao J, Deng Y, Xie F. APOE ε4 is associated with decreased synaptic density in cognitively impaired participants. Alzheimers Dement 2024; 20:3157-3166. [PMID: 38477490 PMCID: PMC11095422 DOI: 10.1002/alz.13775] [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: 09/30/2023] [Revised: 02/03/2024] [Accepted: 02/07/2024] [Indexed: 03/14/2024]
Abstract
INTRODUCTION We aimed to investigate the effect of apolipoprotein E4 (APOE) ε4 on synaptic density in cognitively impaired (CI) participants. METHODS One hundred ten CI participants underwent amyloid positron emission tomography (PET) with 18F-florbetapir and synaptic density PET with 18F-SynVesT-1. We evaluated the influence of APOE ε4 allele on synaptic density and investigated the effects of ε4 genotype on the associations of synaptic density with Alzheimer's disease (AD) biomarkers. The mediation effects of AD biomarkers on ε4-associated synaptic density loss were analyzed. RESULTS Compared with non-carriers, APOE ε4 allele carriers exhibited significant synaptic loss in the medial temporal lobe. Amyloid beta (Aβ) and tau pathology mediated the effects of APOE ε4 on synaptic density to different extents. The associations between synaptic density and tau pathology were regulated by the APOE ε4 genotype. DISCUSSION The APOE ε4 allele was associated with decreased synaptic density in CI individuals and may be driven by AD biomarkers.
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Affiliation(s)
- Kun He
- Department of Nuclear Medicine & PET CenterHuashan Hospital, Fudan UniversityShanghaiChina
| | - Binyin Li
- Department of Neurology & Institute of Neurology, Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghaiChina
- Clinical Neuroscience CenterRuijin Hospital LuWan BranchShanghai Jiao Tong University School of MedicineShanghaiChina
| | - Jie Wang
- Department of Nuclear Medicine & PET CenterHuashan Hospital, Fudan UniversityShanghaiChina
| | - Ying Wang
- Department of GerontologyShanghai Jiaotong University Affiliated Sixth People's HospitalShanghaiChina
| | - Zhiwen You
- Department of Nuclear MedicineShanghai East HospitalTongji University School of MedicineShanghaiChina
| | - Xing Chen
- Department of Nuclear MedicineShanghai East HospitalTongji University School of MedicineShanghaiChina
| | - Haijuan Chen
- Department of Neurology & Institute of Neurology, Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghaiChina
| | - Junpeng Li
- Department of Nuclear Medicine & PET CenterHuashan Hospital, Fudan UniversityShanghaiChina
| | - Qi Huang
- Department of Nuclear Medicine & PET CenterHuashan Hospital, Fudan UniversityShanghaiChina
| | - Qihao Guo
- Department of GerontologyShanghai Jiaotong University Affiliated Sixth People's HospitalShanghaiChina
| | - Yiyun Henry Huang
- PET CenterDepartment of Radiology and Biomedical ImagingYale University School of MedicineNew HavenUSA
| | - Yihui Guan
- Department of Nuclear Medicine & PET CenterHuashan Hospital, Fudan UniversityShanghaiChina
| | - Kewei Chen
- Banner Alzheimer InstituteArizona State University, University of Arizona and Arizona Alzheimer's ConsortiumPhoenixUSA
| | - Jun Zhao
- Department of Nuclear MedicineShanghai East HospitalTongji University School of MedicineShanghaiChina
| | - Yulei Deng
- Department of Neurology & Institute of Neurology, Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghaiChina
- Clinical Neuroscience CenterRuijin Hospital LuWan BranchShanghai Jiao Tong University School of MedicineShanghaiChina
| | - Fang Xie
- Department of Nuclear Medicine & PET CenterHuashan Hospital, Fudan UniversityShanghaiChina
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain ScienceFudan UniversityShanghaiChina
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Bavarsad MS, Grinberg LT. SV2A PET imaging in human neurodegenerative diseases. Front Aging Neurosci 2024; 16:1380561. [PMID: 38699560 PMCID: PMC11064927 DOI: 10.3389/fnagi.2024.1380561] [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: 02/01/2024] [Accepted: 03/20/2024] [Indexed: 05/05/2024] Open
Abstract
This manuscript presents a thorough review of synaptic vesicle glycoprotein 2A (SV2A) as a biomarker for synaptic integrity using Positron Emission Tomography (PET) in neurodegenerative diseases. Synaptic pathology, characterized by synaptic loss, has been linked to various brain diseases. Therefore, there is a need for a minimally invasive approach to measuring synaptic density in living human patients. Several radiotracers targeting synaptic vesicle protein 2A (SV2A) have been created and effectively adapted for use in human subjects through PET scans. SV2A is an integral glycoprotein found in the membranes of synaptic vesicles in all synaptic terminals and is widely distributed throughout the brain. The review delves into the development of SV2A-specific PET radiotracers, highlighting their advancements and limitations in neurodegenerative diseases. Among these tracers, 11C-UCB-J is the most used so far. We summarize and discuss an increasing body of research that compares measurements of synaptic density using SV2A PET with other established indicators of neurodegenerative diseases, including cognitive performance and radiological findings, thus providing a comprehensive analysis of SV2A's effectiveness and reliability as a diagnostic tool in contrast to traditional markers. Although the literature overall suggests the promise of SV2A as a diagnostic and therapeutic monitoring tool, uncertainties persist regarding the superiority of SV2A as a biomarker compared to other available markers. The review also underscores the paucity of studies characterizing SV2A distribution and loss in human brain tissue from patients with neurodegenerative diseases, emphasizing the need to generate quantitative neuropathological maps of SV2A density in cases with neurodegenerative diseases to fully harness the potential of SV2A PET imaging in clinical settings. We conclude by outlining future research directions, stressing the importance of integrating SV2A PET imaging with other biomarkers and clinical assessments and the need for longitudinal studies to track SV2A changes throughout neurodegenerative disease progression, which could lead to breakthroughs in early diagnosis and the evaluation of new treatments.
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Affiliation(s)
| | - Lea T. Grinberg
- Memory and Aging Center, Weill Institute for Neurosciences, University of California, San Francisco (UCSF), San Francisco, CA, United States
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Wang J, Huang Q, Chen X, You Z, He K, Guo Q, Huang Y, Yang Y, Lin Z, Guo T, Zhao J, Guan Y, Li B, Xie F. Tau pathology is associated with synaptic density and longitudinal synaptic loss in Alzheimer's disease. Mol Psychiatry 2024:10.1038/s41380-024-02501-z. [PMID: 38589563 DOI: 10.1038/s41380-024-02501-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 02/23/2024] [Accepted: 02/27/2024] [Indexed: 04/10/2024]
Abstract
The associations of synaptic loss with amyloid-β (Aβ) and tau pathology measured by positron emission tomography (PET) and plasma analysis in Alzheimer's disease (AD) patients are unknown. Seventy-five participants, including 26 AD patients, 19 mild cognitive impairment (MCI) patients, and 30 normal controls (NCs), underwent [18F]SynVesT-1 PET/MR scans to assess synaptic density and [18F]florbetapir and [18F]MK6240 PET/CT scans to evaluate Aβ plaques and tau tangles. Among them, 19 AD patients, 12 MCI patients, and 29 NCs had plasma Aβ42/40 and p-tau181 levels measured by the Simoa platform. Twenty-three individuals, 6 AD patients, 4 MCI patients, and 13 NCs, underwent [18F]SynVesT-1 PET/MRI and [18F]MK6240 PET/CT scans during a one-year follow-up assessment. The associations of Aβ and tau pathology with cross-sectional and longitudinal synaptic loss were investigated using Pearson correlation analyses, generalized linear models and mediation analyses. AD patients exhibited lower synaptic density than NCs and MCI patients. In the whole cohort, global Aβ deposition was associated with synaptic loss in the medial (r = -0.431, p < 0.001) and lateral (r = -0.406, p < 0.001) temporal lobes. Synaptic density in almost all regions was related to the corresponding regional tau tangles independent of global Aβ deposition in the whole cohort and stratified groups. Synaptic density in the medial and lateral temporal lobes was correlated with plasma Aβ42/40 (r = 0.300, p = 0.020/r = 0.289, p = 0.025) and plasma p-tau 181 (r = -0.412, p = 0.001/r = -0.529, p < 0.001) levels in the whole cohort. Mediation analyses revealed that tau tangles mediated the relationship between Aβ plaques and synaptic density in the whole cohort. Baseline tau pathology was positively associated with longitudinal synaptic loss. This study suggested that tau burden is strongly linked to synaptic density independent of Aβ plaques, and also can predict longitudinal synaptic loss.
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Affiliation(s)
- Jie Wang
- Department of Nuclear Medicine & PET Center, Huashan Hospital, Fudan University, Shanghai, 200040, China
| | - Qi Huang
- Department of Nuclear Medicine & PET Center, Huashan Hospital, Fudan University, Shanghai, 200040, China
| | - Xing Chen
- Department of Nuclear Medicine, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 310000, China
| | - Zhiwen You
- Department of Nuclear Medicine, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 310000, China
| | - Kun He
- Department of Nuclear Medicine & PET Center, Huashan Hospital, Fudan University, Shanghai, 200040, China
| | - Qihao Guo
- Department of Gerontology, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai, 200233, China
| | - Yiyun Huang
- PET Center, Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, Connecticut, CT, 06520-8048, USA
| | - Yang Yang
- Beijing United Imaging Research Institute of Intelligent Imaging, Beijing, 100089, China
| | - Zengping Lin
- Central Research Institute, United Imaging Healthcare Group Co., Ltd, Shanghai, 201807, China
| | - Tengfei Guo
- Institute of Biomedical Engineering, Shenzhen Bay Laboratory, Shenzhen, 518000, China
| | - Jun Zhao
- Department of Nuclear Medicine, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 310000, China
| | - Yihui Guan
- Department of Nuclear Medicine & PET Center, Huashan Hospital, Fudan University, Shanghai, 200040, China.
| | - Binyin Li
- Department of Neurology and Institute of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.
| | - Fang Xie
- Department of Nuclear Medicine & PET Center, Huashan Hospital, Fudan University, Shanghai, 200040, China.
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9
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He Y, Xie F. In vitro evaluation of PET radiotracers reflecting multidimensionality of Alzheimer's disease: building more roadmaps for clinical translation. AMERICAN JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING 2024; 14:78-81. [PMID: 38500741 PMCID: PMC10944376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 02/17/2024] [Accepted: 02/18/2024] [Indexed: 03/20/2024]
Abstract
In the current issue of American Journal of Nuclear Medicine and Molecular Imaging, Vasdev et al. presented a work entitled "In Vitro Evaluation of PET Radiotracers for Imaging Synaptic Density, the Acetylcholine Transporter, AMPA-tarp-γ8 and Muscarinic M4 receptors in Alzheimer's disease". In which, in vitro autoradiography studies using radioligands were employed as a valuable tool to gain more insights for potential clinical translation. In this invited perspective, we would like to briefly introduce the current state of AD diagnosis, especially PET imaging on synapse, and highlight the advances of PET imaging in pre-clinic and clinic that might assist on precise therapy in the future.
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Affiliation(s)
- Yingfang He
- Institute of Radiation Medicine, Fudan UniversityNo. 2094 Xietu Road, Shanghai 200032, China
| | - Fang Xie
- Department of Nuclear Medicine and PET Center, Huashan Hospital, Fudan UniversityShanghai 200230, China
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10
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Visser M, O'Brien JT, Mak E. In vivo imaging of synaptic density in neurodegenerative disorders with positron emission tomography: A systematic review. Ageing Res Rev 2024; 94:102197. [PMID: 38266660 DOI: 10.1016/j.arr.2024.102197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 01/09/2024] [Accepted: 01/12/2024] [Indexed: 01/26/2024]
Abstract
Positron emission tomography (PET) with radiotracers that bind to synaptic vesicle glycoprotein 2 A (SV2A) enables quantification of synaptic density in the living human brain. Assessing the regional distribution and severity of synaptic density loss will contribute to our understanding of the pathological processes that precede atrophy in neurodegeneration. In this systematic review, we provide a discussion of in vivo SV2A PET imaging research for quantitative assessment of synaptic density in various dementia conditions: amnestic Mild Cognitive Impairment and Alzheimer's disease, Frontotemporal dementia, Progressive supranuclear palsy and Corticobasal degeneration, Parkinson's disease and Dementia with Lewy bodies, Huntington's disease, and Spinocerebellar Ataxia. We discuss the main findings concerning group differences and clinical-cognitive correlations, and explore relations between SV2A PET and other markers of pathology. Additionally, we touch upon synaptic density in healthy ageing and outcomes of radiotracer validation studies. Studies were identified on PubMed and Embase between 2018 and 2023; last searched on the 3rd of July 2023. A total of 36 studies were included, comprising 5 on normal ageing, 21 clinical studies, and 10 validation studies. Extracted study characteristics were participant details, methodological aspects, and critical findings. In summary, the small but growing literature on in vivo SV2A PET has revealed different spatial patterns of synaptic density loss among various neurodegenerative disorders that correlate with cognitive functioning, supporting the potential role of SV2A PET imaging for differential diagnosis. SV2A PET imaging shows tremendous capability to provide novel insights into the aetiology of neurodegenerative disorders and great promise as a biomarker for synaptic density reduction. Novel directions for future synaptic density research are proposed, including (a) longitudinal imaging in larger patient cohorts of preclinical dementias, (b) multi-modal mapping of synaptic density loss onto other pathological processes, and (c) monitoring therapeutic responses and assessing drug efficacy in clinical trials.
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Affiliation(s)
- Malouke Visser
- Department of Psychiatry, School of Clinical Medicine, Addenbrooke's Hospital, University of Cambridge, United Kingdom; Neuropsychology and Rehabilitation Psychology, Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, the Netherlands
| | - John T O'Brien
- Department of Psychiatry, School of Clinical Medicine, Addenbrooke's Hospital, University of Cambridge, United Kingdom
| | - Elijah Mak
- Department of Psychiatry, School of Clinical Medicine, Addenbrooke's Hospital, University of Cambridge, United Kingdom.
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11
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Wang J, He Y, Chen X, Huang L, Li J, You Z, Huang Q, Ren S, He K, Schibli R, Mu L, Guan Y, Guo Q, Zhao J, Xie F. Metabotropic glutamate receptor 5 (mGluR5) is associated with neurodegeneration and amyloid deposition in Alzheimer's disease: A [ 18F]PSS232 PET/MRI study. Alzheimers Res Ther 2024; 16:9. [PMID: 38217040 PMCID: PMC10785459 DOI: 10.1186/s13195-024-01385-z] [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: 07/05/2023] [Accepted: 01/04/2024] [Indexed: 01/14/2024]
Abstract
BACKGROUND Metabotropic glutamate receptor 5 (mGluR5) is involved in regulating integrative brain function and synaptic transmission. Aberrant mGluR5 signaling and relevant synaptic failure play a key role in the initial pathophysiological mechanism of Alzheimer's disease (AD). The study aims to investigate the association between mGluR5 availability and AD's biomarkers and cognitive function. METHODS We examined 35 individuals with mGluR5 tracer [18F]PSS232 to assess mGluR5 availability, and with [18F]Florbetapir PET to assess global amyloid deposition, and [18F]FDG PET to assess glucose metabolism. The plasma neurofilament light (NfL) and p-tau181 levels in a subset of individuals were measured (n = 27). The difference in mGluR5 availability between the AD and normal control (NC) groups was explored. The associations of mGluR5 availability with amyloid deposition, glucose metabolism, gray matter volume (GMV), neuropsychological assessment scores, and plasma biomarkers were analyzed. RESULTS The mGluR5 availability was significantly reduced in AD patients' hippocampus and parahippocampal gyrus compared to NCs. Global amyloid deposition was positively associated with mGluR5 availability in the AD group and reversely associated in the NC group. The mGluR5 availability was positively correlated with regional glucose metabolism in the overall and stratified analyses. The availability of mGluR5 in the hippocampus and parahippocampal gyrus demonstrated a strong relationship with the GMV of the medial temporal lobe, plasma p-tau181 or NfL levels, and global cognitive performance. CONCLUSIONS [18F]PSS232 PET can quantify the changes of mGluR5 availability in the progression of AD. mGluR5 availability correlated not only with neuropathological biomarkers of AD but also with neurodegenerative biomarkers and cognitive performance. mGluR5 may be a novel neurodegenerative biomarker, and whether mGluR5 could be a potential therapeutic target for AD needs to be further studied.
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Affiliation(s)
- Jie Wang
- Department of Nuclear Medicine &PET Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Yingfang He
- Department of Chemistry and Applied Biosciences, Center for Radiopharmaceutical Sciences, Institute of Pharmaceutical Sciences, ETH Zurich, CH-8093, Zurich, Switzerland
| | - Xing Chen
- Department of Nuclear Medicine, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Lin Huang
- Department of Gerontology, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Junpeng Li
- Department of Nuclear Medicine &PET Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Zhiwen You
- Department of Nuclear Medicine, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Qi Huang
- Department of Nuclear Medicine &PET Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Shuhua Ren
- Department of Nuclear Medicine &PET Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Kun He
- Department of Nuclear Medicine &PET Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Roger Schibli
- Department of Chemistry and Applied Biosciences, Center for Radiopharmaceutical Sciences, Institute of Pharmaceutical Sciences, ETH Zurich, CH-8093, Zurich, Switzerland
| | - Linjing Mu
- Department of Chemistry and Applied Biosciences, Center for Radiopharmaceutical Sciences, Institute of Pharmaceutical Sciences, ETH Zurich, CH-8093, Zurich, Switzerland
| | - Yihui Guan
- Department of Nuclear Medicine &PET Center, Huashan Hospital, Fudan University, Shanghai, China.
| | - Qihao Guo
- Department of Gerontology, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai, China.
| | - Jun Zhao
- Department of Nuclear Medicine, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China.
| | - Fang Xie
- Department of Nuclear Medicine &PET Center, Huashan Hospital, Fudan University, Shanghai, China.
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12
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Mandino F, Shen X, Desrosiers-Gregoire G, O'Connor D, Mukherjee B, Owens A, Qu A, Onofrey J, Papademetris X, Chakravarty MM, Strittmatter SM, Lake EM. Aging-Dependent Loss of Connectivity in Alzheimer's Model Mice with Rescue by mGluR5 Modulator. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.12.15.571715. [PMID: 38260465 PMCID: PMC10802481 DOI: 10.1101/2023.12.15.571715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Amyloid accumulation in Alzheimer's disease (AD) is associated with synaptic damage and altered connectivity in brain networks. While measures of amyloid accumulation and biochemical changes in mouse models have utility for translational studies of certain therapeutics, preclinical analysis of altered brain connectivity using clinically relevant fMRI measures has not been well developed for agents intended to improve neural networks. Here, we conduct a longitudinal study in a double knock-in mouse model for AD ( App NL-G-F /hMapt ), monitoring brain connectivity by means of resting-state fMRI. While the 4-month-old AD mice are indistinguishable from wild-type controls (WT), decreased connectivity in the default-mode network is significant for the AD mice relative to WT mice by 6 months of age and is pronounced by 9 months of age. In a second cohort of 20-month-old mice with persistent functional connectivity deficits for AD relative to WT, we assess the impact of two-months of oral treatment with a silent allosteric modulator of mGluR5 (BMS-984923) known to rescue synaptic density. Functional connectivity deficits in the aged AD mice are reversed by the mGluR5-directed treatment. The longitudinal application of fMRI has enabled us to define the preclinical time trajectory of AD-related changes in functional connectivity, and to demonstrate a translatable metric for monitoring disease emergence, progression, and response to synapse-rescuing treatment.
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13
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Dejanovic B, Sheng M, Hanson JE. Targeting synapse function and loss for treatment of neurodegenerative diseases. Nat Rev Drug Discov 2024; 23:23-42. [PMID: 38012296 DOI: 10.1038/s41573-023-00823-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/06/2023] [Indexed: 11/29/2023]
Abstract
Synapse dysfunction and loss are hallmarks of neurodegenerative diseases that correlate with cognitive decline. However, the mechanisms and therapeutic strategies to prevent or reverse synaptic damage remain elusive. In this Review, we discuss recent advances in understanding the molecular and cellular pathways that impair synapses in neurodegenerative diseases, including the effects of protein aggregation and neuroinflammation. We also highlight emerging therapeutic approaches that aim to restore synaptic function and integrity, such as enhancing synaptic plasticity, preventing synaptotoxicity, modulating neuronal network activity and targeting immune signalling. We discuss the preclinical and clinical evidence for each strategy, as well as the challenges and opportunities for developing effective synapse-targeting therapeutics for neurodegenerative diseases.
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Affiliation(s)
| | - Morgan Sheng
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Jesse E Hanson
- Department of Neuroscience, Genentech, South San Francisco, CA, USA.
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14
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Whiteside DJ, Holland N, Tsvetanov KA, Mak E, Malpetti M, Savulich G, Jones PS, Naessens M, Rouse MA, Fryer TD, Hong YT, Aigbirhio FI, Mulroy E, Bhatia KP, Rittman T, O'Brien JT, Rowe JB. Synaptic density affects clinical severity via network dysfunction in syndromes associated with frontotemporal lobar degeneration. Nat Commun 2023; 14:8458. [PMID: 38114493 PMCID: PMC10730886 DOI: 10.1038/s41467-023-44307-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Accepted: 12/07/2023] [Indexed: 12/21/2023] Open
Abstract
There is extensive synaptic loss from frontotemporal lobar degeneration, in preclinical models and human in vivo and post mortem studies. Understanding the consequences of synaptic loss for network function is important to support translational models and guide future therapeutic strategies. To examine this relationship, we recruited 55 participants with syndromes associated with frontotemporal lobar degeneration and 24 healthy controls. We measured synaptic density with positron emission tomography using the radioligand [11C]UCB-J, which binds to the presynaptic vesicle glycoprotein SV2A, neurite dispersion with diffusion magnetic resonance imaging, and network function with task-free magnetic resonance imaging functional connectivity. Synaptic density and neurite dispersion in patients was associated with reduced connectivity beyond atrophy. Functional connectivity moderated the relationship between synaptic density and clinical severity. Our findings confirm the importance of synaptic loss in frontotemporal lobar degeneration syndromes, and the resulting effect on behaviour as a function of abnormal connectivity.
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Affiliation(s)
- David J Whiteside
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK.
- Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK.
| | - Negin Holland
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
- Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | - Kamen A Tsvetanov
- Medical Research Council Cognition and Brain Sciences Unit, University of Cambridge, Cambridge, UK
| | - Elijah Mak
- Department of Psychiatry, University of Cambridge, Cambridge, UK
| | - Maura Malpetti
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
- Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | - George Savulich
- Department of Psychiatry, University of Cambridge, Cambridge, UK
| | - P Simon Jones
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Michelle Naessens
- Medical Research Council Cognition and Brain Sciences Unit, University of Cambridge, Cambridge, UK
| | - Matthew A Rouse
- Medical Research Council Cognition and Brain Sciences Unit, University of Cambridge, Cambridge, UK
| | - Tim D Fryer
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
- Wolfson Brain Imaging Centre, University of Cambridge, Cambridge, UK
| | - Young T Hong
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
- Wolfson Brain Imaging Centre, University of Cambridge, Cambridge, UK
| | - Franklin I Aigbirhio
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
- Wolfson Brain Imaging Centre, University of Cambridge, Cambridge, UK
| | - Eoin Mulroy
- UCL Queen Square Institute of Neurology, University College London, London, WC1N 3BG, UK
| | - Kailash P Bhatia
- UCL Queen Square Institute of Neurology, University College London, London, WC1N 3BG, UK
| | - Timothy Rittman
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
- Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | - John T O'Brien
- Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
- Department of Psychiatry, University of Cambridge, Cambridge, UK
| | - James B Rowe
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
- Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
- Medical Research Council Cognition and Brain Sciences Unit, University of Cambridge, Cambridge, UK
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15
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Zhao Y, Guo Q, Zhang Y, Zheng J, Yang Y, Du X, Feng H, Zhang S. Application of Deep Learning for Prediction of Alzheimer's Disease in PET/MR Imaging. Bioengineering (Basel) 2023; 10:1120. [PMID: 37892850 PMCID: PMC10604050 DOI: 10.3390/bioengineering10101120] [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: 08/21/2023] [Revised: 09/19/2023] [Accepted: 09/22/2023] [Indexed: 10/29/2023] Open
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disorder that affects millions of people worldwide. Positron emission tomography/magnetic resonance (PET/MR) imaging is a promising technique that combines the advantages of PET and MR to provide both functional and structural information of the brain. Deep learning (DL) is a subfield of machine learning (ML) and artificial intelligence (AI) that focuses on developing algorithms and models inspired by the structure and function of the human brain's neural networks. DL has been applied to various aspects of PET/MR imaging in AD, such as image segmentation, image reconstruction, diagnosis and prediction, and visualization of pathological features. In this review, we introduce the basic concepts and types of DL algorithms, such as feed forward neural networks, convolutional neural networks, recurrent neural networks, and autoencoders. We then summarize the current applications and challenges of DL in PET/MR imaging in AD, and discuss the future directions and opportunities for automated diagnosis, predictions of models, and personalized medicine. We conclude that DL has great potential to improve the quality and efficiency of PET/MR imaging in AD, and to provide new insights into the pathophysiology and treatment of this devastating disease.
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Affiliation(s)
- Yan Zhao
- Department of Information Center, The First Affiliated Hospital, Dalian Medical University, Dalian 116011, China
| | - Qianrui Guo
- Department of Nuclear Medicine, Beijing Cancer Hospital, Beijing 100142, China;
| | - Yukun Zhang
- Department of Radiology, The First Affiliated Hospital, Dalian Medical University, Dalian 116011, China
| | - Jia Zheng
- Department of Nuclear Medicine, The First Affiliated Hospital, Dalian Medical University, Dalian 116011, China
| | - Yang Yang
- Beijing United Imaging Research Institute of Intelligent Imaging, Beijing 100094, China
| | - Xuemei Du
- Department of Nuclear Medicine, The First Affiliated Hospital, Dalian Medical University, Dalian 116011, China
| | - Hongbo Feng
- Department of Nuclear Medicine, The First Affiliated Hospital, Dalian Medical University, Dalian 116011, China
| | - Shuo Zhang
- Department of Nuclear Medicine, The First Affiliated Hospital, Dalian Medical University, Dalian 116011, China
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16
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Lopes CR, Silva AC, Silva HB, Canas PM, Agostinho P, Cunha RA, Lopes JP. Adenosine A 2A Receptor Up-Regulation Pre-Dates Deficits of Synaptic Plasticity and of Memory in Mice Exposed to Aβ 1-42 to Model Early Alzheimer's Disease. Biomolecules 2023; 13:1173. [PMID: 37627238 PMCID: PMC10452250 DOI: 10.3390/biom13081173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 07/19/2023] [Accepted: 07/26/2023] [Indexed: 08/27/2023] Open
Abstract
The intracerebroventricular (icv) injection of amyloid peptides (Aβ) models Alzheimer's disease (AD) in mice, as typified by the onset within 15 days of deficits of memory and of hippocampal long-term potentiation (LTP) that are prevented by the blockade of adenosine A2A receptors (A2AR). Since A2AR overfunction is sufficient to trigger memory deficits, we tested if A2AR were upregulated in hippocampal synapses before the onset of memory deficits to support the hypothesis that A2AR overfunction could be a trigger of AD. Six to eight days after Aβ-icv injection, mice displayed no alterations of hippocampal dependent memory; however, they presented an increased excitability of hippocampal synapses, a slight increase in LTP magnitude in Schaffer fiber-CA1 pyramid synapses and an increased density of A2AR in hippocampal synapses. A2AR blockade with SCH58261 (50 nM) normalized excitability and LTP in hippocampal slices from mice sacrificed 7-8 days after Aβ-icv injection. Fifteen days after Aβ-icv injection, mice displayed evident deficits of hippocampal-dependent memory deterioration, with reduced hippocampal CA1 LTP but no hyperexcitability and a sustained increase in synaptic A2AR, which blockade restored LTP magnitude. This shows that the upregulation of synaptic A2AR precedes the onset of deterioration of memory and of hippocampal synaptic plasticity, supporting the hypothesis that the overfunction of synaptic A2AR could be a trigger of memory deterioration in AD.
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Affiliation(s)
- Cátia R. Lopes
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal; (C.R.L.); (A.C.S.); (H.B.S.); (P.M.C.); (P.A.); (J.P.L.)
- Faculty of Medicine, University of Coimbra, 3000-370 Coimbra, Portugal
| | - António C. Silva
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal; (C.R.L.); (A.C.S.); (H.B.S.); (P.M.C.); (P.A.); (J.P.L.)
| | - Henrique B. Silva
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal; (C.R.L.); (A.C.S.); (H.B.S.); (P.M.C.); (P.A.); (J.P.L.)
| | - Paula M. Canas
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal; (C.R.L.); (A.C.S.); (H.B.S.); (P.M.C.); (P.A.); (J.P.L.)
| | - Paula Agostinho
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal; (C.R.L.); (A.C.S.); (H.B.S.); (P.M.C.); (P.A.); (J.P.L.)
- Faculty of Medicine, University of Coimbra, 3000-370 Coimbra, Portugal
| | - Rodrigo A. Cunha
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal; (C.R.L.); (A.C.S.); (H.B.S.); (P.M.C.); (P.A.); (J.P.L.)
- Faculty of Medicine, University of Coimbra, 3000-370 Coimbra, Portugal
| | - João Pedro Lopes
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal; (C.R.L.); (A.C.S.); (H.B.S.); (P.M.C.); (P.A.); (J.P.L.)
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17
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Pisani A, Paciello F, Del Vecchio V, Malesci R, De Corso E, Cantone E, Fetoni AR. The Role of BDNF as a Biomarker in Cognitive and Sensory Neurodegeneration. J Pers Med 2023; 13:jpm13040652. [PMID: 37109038 PMCID: PMC10140880 DOI: 10.3390/jpm13040652] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 04/04/2023] [Accepted: 04/08/2023] [Indexed: 04/29/2023] Open
Abstract
Brain-derived neurotrophic factor (BDNF) has a crucial function in the central nervous system and in sensory structures including olfactory and auditory systems. Many studies have highlighted the protective effects of BDNF in the brain, showing how it can promote neuronal growth and survival and modulate synaptic plasticity. On the other hand, conflicting data about BDNF expression and functions in the cochlear and in olfactory structures have been reported. Several clinical and experimental research studies showed alterations in BDNF levels in neurodegenerative diseases affecting the central and peripheral nervous system, suggesting that BDNF can be a promising biomarker in most neurodegenerative conditions, including Alzheimer's disease, shearing loss, or olfactory impairment. Here, we summarize current research concerning BDNF functions in brain and in sensory domains (olfaction and hearing), focusing on the effects of the BDNF/TrkB signalling pathway activation in both physiological and pathological conditions. Finally, we review significant studies highlighting the possibility to target BDNF as a biomarker in early diagnosis of sensory and cognitive neurodegeneration, opening new opportunities to develop effective therapeutic strategies aimed to counteract neurodegeneration.
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Affiliation(s)
- Anna Pisani
- Department of Otolaryngology Head and Neck Surgery, Università Cattolica del Sacro Cuore, 00168 Rome, Italy
| | - Fabiola Paciello
- Department of Neuroscience, Università Cattolica del Sacro Cuore, 00168 Rome, Italy
- Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy
| | - Valeria Del Vecchio
- Department of Neuroscience, Reproductive Sciences and Dentistry-Audiology Section, University of Naples Federico II, 80131 Naples, Italy
| | - Rita Malesci
- Department of Neuroscience, Reproductive Sciences and Dentistry-Audiology Section, University of Naples Federico II, 80131 Naples, Italy
| | - Eugenio De Corso
- Department of Otolaryngology Head and Neck Surgery, Università Cattolica del Sacro Cuore, 00168 Rome, Italy
- Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168 Rome, Italy
| | - Elena Cantone
- Department of Neuroscience, Reproductive Sciences and Dentistry-ENT Section, University of Naples Federico II, 80131 Naples, Italy
| | - Anna Rita Fetoni
- Department of Neuroscience, Reproductive Sciences and Dentistry-Audiology Section, University of Naples Federico II, 80131 Naples, Italy
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18
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Lu J, Huang R, Peng Y, Zhang J, Liang K, Wang Y, Feng Y, Wang Z. Mendelian Randomization Analyses Accounting for Causal Effect of COVID-19 on Brain Imaging-Derived Phenotypes. J Alzheimers Dis 2023; 96:1059-1070. [PMID: 37955088 DOI: 10.3233/jad-230626] [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: 11/14/2023]
Abstract
BACKGROUND The coronavirus disease 2019 (COVID-19) has been a major challenge to global health and a financial burden. Little is known regarding the possible causal effects of COVID-19 on the macro- and micro-structures of the human brain. OBJECTIVE To determine the causal links between susceptibility, hospitalization, and the severity of COVID-19 and brain imaging-derived phenotypes (IDPs). METHODS Mendelian randomization (MR) analyses were performed to investigate the causal effect of three COVID-19 exposures (SARS-CoV-2 infection, hospitalized COVID-19, and critical COVID-19) on brain structure employing summary datasets of genome-wide association studies. RESULTS In terms of cortical phenotypes, hospitalization due to COVID-19 was associated with a global decrease in the surface area (SA) of the cortex structure (β= -624.77, 95% CI: -1227.88 to -21.66, p = 0.042). At the regional level, SARS-CoV-2 infection was found to have a nominally causal effect on the thickness (TH) of the postcentral region (β= -0.004, 95% CI: -0.007 to -0.001, p = 0.01), as well as eight other IDPs. Hospitalized COVID-19 has a nominally causal relationship with TH of postcentral (β= -0.004, 95% CI: -0.007 to -0.001, p = 0.01) and other 6 IDPs. The nominally causal effects of critical COVID-19 on TH of medial orbitofrontal (β=0.004, 95% CI: 0.001to 0.007, p = 0.004) and other 7 IDPs were revealed. CONCLUSIONS Our study provides compelling genetic evidence supporting causal relationships between three COVID-19 traits and brain IDPs. This discovery holds promise for enhancing predictions and interventions in brain imaging.
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Affiliation(s)
- Jiajie Lu
- Institute of Neuroscience, Department of Neurosurgery, the Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
- Department of Clinical Medicine, The Second Clinical School of Guangzhou Medical University, Guangzhou, China
| | - Rihong Huang
- Institute of Neuroscience, Department of Neurosurgery, the Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
- Department of Clinical Medicine, The Second Clinical School of Guangzhou Medical University, Guangzhou, China
| | - Yuecheng Peng
- Institute of Neuroscience, Department of Neurosurgery, the Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
- Department of Clinical Medicine, The Second Clinical School of Guangzhou Medical University, Guangzhou, China
| | - Jinming Zhang
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Kairong Liang
- Institute of Neuroscience, Department of Neurosurgery, the Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Yezhong Wang
- Institute of Neuroscience, Department of Neurosurgery, the Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Yi Feng
- Department of Thoracic Surgery and Oncology, China State Key Laboratory of Respiratory Disease & National Clinical Research Center for Respiratory Disease, the First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
- Guangzhou Institute of Respiratory Health, Guangzhou, China
| | - Zhaotao Wang
- Institute of Neuroscience, Department of Neurosurgery, the Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
- Department of Clinical Medicine, The Second Clinical School of Guangzhou Medical University, Guangzhou, China
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