1
|
Kang DW, Wang SM, Um YH, Kim NY, Lee CU, Lim HK. Associations Between Sub-Threshold Amyloid-β Deposition, Cortical Volume, and Cognitive Function Modulated by APOE ɛ4 Carrier Status in Cognitively Normal Older Adults. J Alzheimers Dis 2022; 89:1003-1016. [PMID: 35964194 PMCID: PMC9535581 DOI: 10.3233/jad-220427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Background: There has been renewed interest in the deteriorating effects of sub-threshold amyloid-β (Aβ) accumulation in Alzheimer’s disease (AD). Despite evidence suggesting a synergistic interaction between the APOE ɛ4 allele and Aβ deposition in neurodegeneration, few studies have investigated the modulatory role of this allele in sub-threshold Aβ deposition during the preclinical phase. Objective: We aimed to explore the differential effect of the APOE ɛ4 carrier status on the association between sub-threshold Aβ deposition, cortical volume, and cognitive performance in cognitively normal older adults (CN). Methods: A total of 112 CN with sub-threshold Aβ deposition was included in the study. Participants underwent structural magnetic resonance imaging, [18F] flutemetamol PET-CT, and a neuropsychological battery. Potential interactions between APOE ɛ4 carrier status, Aβ accumulation, and cognitive function for cortical volume were assessed with whole-brain voxel-wise analysis. Results: We found that greater cortical volume was observed with higher regional Aβ deposition in the APOE ɛ4 carriers, which could be attributed to an interaction between the APOE ɛ4 carrier status and regional Aβ deposition in the posterior cingulate cortex/precuneus. Finally, the APOE ɛ4 carrier status-neuropsychological test score interaction demonstrated a significant effect on the gray matter volume of the left middle occipital gyrus. Conclusion: There might be a compensatory response to initiating Aβ in APOE ɛ4 carriers during the earliest AD stage. Despite its exploratory nature, this study offers some insight into recent interests concerning probabilistic AD modeling, focusing on the modulating role of the APOE ɛ4 carrier status during the preclinical period.
Collapse
Affiliation(s)
- Dong Woo Kang
- Department of Psychiatry, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Sheng-Min Wang
- Department of Psychiatry, Yeouido St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Yoo Hyun Um
- Department of Psychiatry, St. Vincent's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Nak Young Kim
- Department of Psychiatry, Keyo Hospital, Uiwang, Republic of Korea
| | - Chang Uk Lee
- Department of Psychiatry, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Hyun Kook Lim
- Department of Psychiatry, Yeouido St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| |
Collapse
|
2
|
Fowler CF, Goerzen D, Devenyi GA, Madularu D, Chakravarty MM, Near J. OUP accepted manuscript. Brain Commun 2022; 4:fcac072. [PMID: 35434622 PMCID: PMC9007326 DOI: 10.1093/braincomms/fcac072] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 01/12/2022] [Accepted: 03/16/2022] [Indexed: 11/13/2022] Open
Affiliation(s)
- Caitlin F. Fowler
- Department of Biological and Biomedical Engineering, McGill University, Duff Medical Building, Montreal, Canada H3A 2B4
- Centre d’Imagerie Cérébrale, Douglas Mental Health University Institute, Verdun, Canada H4H 1R3
- Correspondence to: Caitlin F. Fowler, CIC Pavilion Office GH-2113 Douglas Mental Health University Institute 6875 Boulevard LaSalle Montreal, Canada H4H 1R3 E-mail:
| | - Dana Goerzen
- Centre d’Imagerie Cérébrale, Douglas Mental Health University Institute, Verdun, Canada H4H 1R3
| | - Gabriel A. Devenyi
- Centre d’Imagerie Cérébrale, Douglas Mental Health University Institute, Verdun, Canada H4H 1R3
- Department of Psychiatry, McGill University, Montreal, Canada H3A 1A1
| | - Dan Madularu
- Centre for Translational NeuroImaging, Northeastern University, Boston, USA
| | - M. Mallar Chakravarty
- Department of Biological and Biomedical Engineering, McGill University, Duff Medical Building, Montreal, Canada H3A 2B4
- Centre d’Imagerie Cérébrale, Douglas Mental Health University Institute, Verdun, Canada H4H 1R3
- Department of Psychiatry, McGill University, Montreal, Canada H3A 1A1
| | - Jamie Near
- Department of Biological and Biomedical Engineering, McGill University, Duff Medical Building, Montreal, Canada H3A 2B4
- Centre d’Imagerie Cérébrale, Douglas Mental Health University Institute, Verdun, Canada H4H 1R3
- Department of Psychiatry, McGill University, Montreal, Canada H3A 1A1
- Physical Studies Research Platform, Sunnybrook Research Institute, Toronto, Canada M4N 3M5
- Department of Medical Biophysics, University of Toronto, Toronto, Canada M5G 1L7
| |
Collapse
|
3
|
Cabral RF, Corrêa DG, Zimmermann N, Tukamoto G, Kubo TTA, Fonseca RP, Silva MM, Wilner NV, Bahia PRV, Gasparetto EL, Marchiori E. Preliminary comparative study of cortical thickness in HIV-infected patients with and without working memory deficit. PLoS One 2021; 16:e0261208. [PMID: 34890434 PMCID: PMC8664225 DOI: 10.1371/journal.pone.0261208] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 11/25/2021] [Indexed: 11/18/2022] Open
Abstract
Purpose Changes in cerebral cortical regions occur in HIV-infected patients, even in those with mild neurocognitive disorders. Working memory / attention is one of the most affected cognitive domain in these patients, worsening their quality of life. Our objective was to assess whether cortical thickness differs between HIV-infected patients with and without working memory deficit. Methods Forty-one adult HIV-infected patients with and without working memory deficit were imaged on a 1.5 T scanner. Working memory deficit was classified by composite Z scores for performance on the Digits and Letter-Number Sequencing subtests of the Wechsler Adult Intelligence Scale (third edition; WAIS-III). Cortical thickness was determined using FreeSurfer software. Differences in mean cortical thickness between groups, corrected for multiple comparisons using Monte-Carlo simulation, were examined using the query design estimate contrast tool of the FreeSurfer software. Results Greater cortical thickness in left pars opercularis of the inferior frontal gyrus, and rostral and caudal portions of the left middle frontal gyrus (cluster 1; p = .004), and left superior frontal gyrus (cluster 2; p = .004) was observed in HIV-infected patients with working memory deficit compared with those without such deficit. Negative correlations were found between WAIS-III–based Z scores and cortical thickness in the two clusters (cluster 1: ρ = –0.59; cluster 2: ρ = –0.47). Conclusion HIV-infected patients with working memory deficit have regions of greater thickness in the left frontal cortices compared with those without such deficit, which may reflect increased synaptic contacts and/or an inflammatory response related to the damage caused by HIV infection.
Collapse
Affiliation(s)
- Rafael Ferracini Cabral
- Department of Radiology, Hospital Universitário Clementino Fraga Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
- Department of Radiology, Clínica de Diagnóstico por Imagem—Diagnósticos da America (CDPI-DASA), Rio de Janeiro, Rio de Janeiro, Brazil
- * E-mail:
| | - Diogo Goulart Corrêa
- Department of Radiology, Hospital Universitário Clementino Fraga Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
- Department of Radiology, Clínica de Diagnóstico por Imagem—Diagnósticos da America (CDPI-DASA), Rio de Janeiro, Rio de Janeiro, Brazil
- Department of Radiology, Paulo Niemeyer State Brain Institute, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Nicolle Zimmermann
- Department of Psychology, Paulo Niemeyer State Brain Institute, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Gustavo Tukamoto
- Department of Radiology, Hospital Universitário Clementino Fraga Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
- Department of Radiology, Clínica de Diagnóstico por Imagem—Diagnósticos da America (CDPI-DASA), Rio de Janeiro, Rio de Janeiro, Brazil
| | - Tadeu Takao Almodovar Kubo
- Department of Radiology, Hospital Universitário Clementino Fraga Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
- Department of Radiology, Clínica de Diagnóstico por Imagem—Diagnósticos da America (CDPI-DASA), Rio de Janeiro, Rio de Janeiro, Brazil
| | - Rochele Paz Fonseca
- Department of Psychology, Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Marcos Martins Silva
- Department of Neurology, Hospital Universitário Clementino Fraga Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Nina Ventura Wilner
- Department of Radiology, Hospital Universitário Clementino Fraga Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
- Department of Radiology, Clínica de Diagnóstico por Imagem—Diagnósticos da America (CDPI-DASA), Rio de Janeiro, Rio de Janeiro, Brazil
- Department of Radiology, Paulo Niemeyer State Brain Institute, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Paulo Roberto Valle Bahia
- Department of Radiology, Hospital Universitário Clementino Fraga Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Emerson Leandro Gasparetto
- Department of Radiology, Hospital Universitário Clementino Fraga Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
- Department of Radiology, Clínica de Diagnóstico por Imagem—Diagnósticos da America (CDPI-DASA), Rio de Janeiro, Rio de Janeiro, Brazil
| | - Edson Marchiori
- Department of Radiology, Hospital Universitário Clementino Fraga Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| |
Collapse
|
4
|
Smit T, Deshayes NAC, Borchelt DR, Kamphuis W, Middeldorp J, Hol EM. Reactive astrocytes as treatment targets in Alzheimer's disease-Systematic review of studies using the APPswePS1dE9 mouse model. Glia 2021; 69:1852-1881. [PMID: 33634529 PMCID: PMC8247905 DOI: 10.1002/glia.23981] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 02/04/2021] [Accepted: 02/08/2021] [Indexed: 12/15/2022]
Abstract
Astrocytes regulate synaptic communication and are essential for proper brain functioning. In Alzheimer's disease (AD) astrocytes become reactive, which is characterized by an increased expression of intermediate filament proteins and cellular hypertrophy. Reactive astrocytes are found in close association with amyloid-beta (Aβ) deposits. Synaptic communication and neuronal network function could be directly modulated by reactive astrocytes, potentially contributing to cognitive decline in AD. In this review, we focus on reactive astrocytes as treatment targets in AD in the APPswePS1dE9 AD mouse model, a widely used model to study amyloidosis and gliosis. We first give an overview of the model; that is, how it was generated, which cells express the transgenes, and the effect of its genetic background on Aβ pathology. Subsequently, to determine whether modifying reactive astrocytes in AD could influence pathogenesis and cognition, we review studies using this mouse model in which interventions were directly targeted at reactive astrocytes or had an indirect effect on reactive astrocytes. Overall, studies specifically targeting astrocytes to reduce astrogliosis showed beneficial effects on cognition, which indicates that targeting astrocytes should be included in developing novel therapies for AD.
Collapse
Affiliation(s)
- Tamar Smit
- Department of Translational NeuroscienceUniversity Medical Center Utrecht Brain Center, Utrecht UniversityUtrechtThe Netherlands
- Swammerdam Institute for Life SciencesCenter for Neuroscience, University of AmsterdamAmsterdamThe Netherlands
| | - Natasja A. C. Deshayes
- Department of Translational NeuroscienceUniversity Medical Center Utrecht Brain Center, Utrecht UniversityUtrechtThe Netherlands
- Swammerdam Institute for Life SciencesCenter for Neuroscience, University of AmsterdamAmsterdamThe Netherlands
| | - David R. Borchelt
- Center for Translational Research in Neurodegenerative Disease, McKnight Brain Institute, Department of NeuroscienceUniversity of Florida College of MedicineGainesvilleFloridaUSA
| | - Willem Kamphuis
- Netherlands Institute for NeuroscienceAn Institute of the Royal Netherlands Academy of Arts and SciencesAmsterdamThe Netherlands
| | - Jinte Middeldorp
- Department of Translational NeuroscienceUniversity Medical Center Utrecht Brain Center, Utrecht UniversityUtrechtThe Netherlands
- Department of ImmunobiologyBiomedical Primate Research CentreRijswijkThe Netherlands
| | - Elly M. Hol
- Department of Translational NeuroscienceUniversity Medical Center Utrecht Brain Center, Utrecht UniversityUtrechtThe Netherlands
| |
Collapse
|
5
|
Sun T, Shi Q, Zhang Y, Power C, Hoesch C, Antonelli S, Schroeder MK, Caldarone BJ, Taudte N, Schenk M, Hettmann T, Schilling S, McDannold NJ, Lemere CA. Focused ultrasound with anti-pGlu3 Aβ enhances efficacy in Alzheimer's disease-like mice via recruitment of peripheral immune cells. J Control Release 2021; 336:443-456. [PMID: 34186148 DOI: 10.1016/j.jconrel.2021.06.037] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 06/22/2021] [Accepted: 06/24/2021] [Indexed: 12/17/2022]
Abstract
Pyroglutamate-3 amyloid-β (pGlu3 Aβ) is an N-terminally modified, pathogenic form of amyloid-β that is present in cerebral amyloid plaques and vascular deposits. Here, we used focused ultrasound (FUS) with microbubbles to enhance the intravenous delivery of an Fc-competent anti-pGlu3 Aβ monoclonal antibody, 07/2a mAb, across the blood brain barrier (BBB) in an attempt to improve Aβ removal and memory in aged APP/PS1dE9 mice, an Alzheimer's disease (AD)-like model of amyloidogenesis. First, we demonstrated that bilateral hippocampal FUS-BBB disruption (FUS-BBBD) led to a 5.5-fold increase of 07/2a mAb delivery to the brains compared to non-sonicated mice 72 h following a single treatment. Then, we determined that three weekly treatments with 07/2a mAb alone improved spatial learning and memory in aged, plaque-rich APP/PS1dE9 mice, and that this improvement occurred faster and in a higher percentage of animals when combined with FUS-BBBD. Mice given the combination treatment had reduced hippocampal plaque burden compared to PBS-treated controls. Furthermore, synaptic protein levels were higher in hippocampal synaptosomes from mice given the combination treatment compared to sham controls, and there were more CA3 synaptic puncta labeled in the APP/PS1dE9 mice given the combination treatment compared to those given mAb alone. Plaque-associated microglia were present in the hippocampi of APP/PS1dE9 mice treated with 07/2a mAb with and without FUS-BBBD. However, we discovered that plaque-associated Ly6G+ monocytes were only present in the hippocampi of APP/PS1dE9 mice that were given FUS-BBBD alone or even more so, the combination treatment. Lastly, FUS-BBBD did not increase the incidence of microhemorrhage in mice with or without 07/2a mAb treatment. Our findings suggest that FUS is a useful tool to enhance delivery and efficacy of an anti-pGlu3 Aβ mAb for immunotherapy either via an additive effect or an independent mechanism. We revealed a potential novel mechanism wherein the combination of 07/2a mAb with FUS-BBBD led to greater monocyte infiltration and recruitment to plaques in this AD-like model. Overall, these effects resulted in greater plaque removal, sparing of synapses and improved cognitive function without causing overt damage, suggesting the possibility of FUS-BBBD as a noninvasive method to increase the therapeutic efficacy of drugs or biologics in AD patients.
Collapse
Affiliation(s)
- Tao Sun
- Focused Ultrasound Laboratory, Department of Radiology, Brigham and Women's Hospital, 75 Francis Street, Boston, MA, United States of America; Harvard Medical School, Boston, MA, United States of America
| | - Qiaoqiao Shi
- Ann Romney Center for Neurologic Diseases in the Department of Neurology, Brigham and Women's Hospital, 75 Francis Street, Boston, MA, United States of America; Harvard Medical School, Boston, MA, United States of America
| | - Yongzhi Zhang
- Focused Ultrasound Laboratory, Department of Radiology, Brigham and Women's Hospital, 75 Francis Street, Boston, MA, United States of America; Harvard Medical School, Boston, MA, United States of America
| | - Chanikarn Power
- Focused Ultrasound Laboratory, Department of Radiology, Brigham and Women's Hospital, 75 Francis Street, Boston, MA, United States of America; Harvard Medical School, Boston, MA, United States of America
| | - Camilla Hoesch
- Ann Romney Center for Neurologic Diseases in the Department of Neurology, Brigham and Women's Hospital, 75 Francis Street, Boston, MA, United States of America
| | - Shawna Antonelli
- Ann Romney Center for Neurologic Diseases in the Department of Neurology, Brigham and Women's Hospital, 75 Francis Street, Boston, MA, United States of America
| | - Maren K Schroeder
- Ann Romney Center for Neurologic Diseases in the Department of Neurology, Brigham and Women's Hospital, 75 Francis Street, Boston, MA, United States of America
| | - Barbara J Caldarone
- Harvard Medical School Mouse Behavior Core, Boston, MA, United States of America
| | - Nadine Taudte
- Fraunhofer Institute for Cell Therapy and Immunology, Department Molecular Drug Biochemistry and Therapy, Halle (Saale), Germany
| | - Mathias Schenk
- Fraunhofer Institute for Cell Therapy and Immunology, Department Molecular Drug Biochemistry and Therapy, Halle (Saale), Germany
| | | | - Stephan Schilling
- Fraunhofer Institute for Cell Therapy and Immunology, Department Molecular Drug Biochemistry and Therapy, Halle (Saale), Germany; Vivoryon Therapeutics AG, Halle (Saale), Germany; Anhalt University of Applied Sciences, Köthen, Germany
| | - Nathan J McDannold
- Focused Ultrasound Laboratory, Department of Radiology, Brigham and Women's Hospital, 75 Francis Street, Boston, MA, United States of America; Harvard Medical School, Boston, MA, United States of America.
| | - Cynthia A Lemere
- Ann Romney Center for Neurologic Diseases in the Department of Neurology, Brigham and Women's Hospital, 75 Francis Street, Boston, MA, United States of America; Harvard Medical School, Boston, MA, United States of America.
| |
Collapse
|
6
|
Seo NY, Kim GH, Noh JE, Shin JW, Lee CH, Lee KJ. Selective Regional Loss of Cortical Synapses Lacking Presynaptic Mitochondria in the 5xFAD Mouse Model. Front Neuroanat 2021; 15:690168. [PMID: 34248509 PMCID: PMC8267061 DOI: 10.3389/fnana.2021.690168] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 05/27/2021] [Indexed: 12/27/2022] Open
Abstract
Synaptic loss in Alzheimer's disease (AD) is strongly correlated with cognitive impairment. Accumulating evidence indicates that amyloid pathology leads to synaptic degeneration and mitochondrial damage in AD. However, it remains unclear whether synapses and presynaptic mitochondria are differentially affected in various cortical regions of the AD brain at the ultrastructural level. Using serial block-face scanning electron microscopy, we assessed synaptic structures in the medial prefrontal cortex (mPFC) and primary visual cortex (V1) of the 5xFAD mouse model of AD. At 6 months of age, 5xFAD mice exhibited significantly elevated levels of amyloid deposition in layer 2/3 of the mPFC but not V1. Accordingly, three-dimensional reconstruction of synaptic connectivity revealed a significant reduction in excitatory synaptic density in layer 2 of the mPFC, but not V1, of male transgenic mice. Notably, the density of synapses lacking presynaptic mitochondria was selectively decreased in the mPFC of 5xFAD mice, with no change in the density of mitochondria-containing synapses. Further classification of spines into shape categories confirmed a preferential loss of thin spines whose presynaptic boutons were largely devoid of mitochondria in the 5xFAD mPFC. Furthermore, the number of mitochondria per bouton in spared mitochondria-containing boutons was reduced in the mPFC, but not V1, of 5xFAD mice. Collectively, these results highlight region-specific vulnerability of cortical synapses to amyloid deposition and suggest that the presence of presynaptic mitochondria may affect synaptic degeneration in AD.
Collapse
Affiliation(s)
- Na-Young Seo
- Neural Circuits Research Group, Korea Brain Research Institute, Daegu, South Korea.,Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu, South Korea
| | - Gyu Hyun Kim
- Neural Circuits Research Group, Korea Brain Research Institute, Daegu, South Korea
| | - Jeong Eun Noh
- Neural Circuits Research Group, Korea Brain Research Institute, Daegu, South Korea
| | - Ji Won Shin
- Neural Circuits Research Group, Korea Brain Research Institute, Daegu, South Korea
| | - Chan Hee Lee
- Neural Circuits Research Group, Korea Brain Research Institute, Daegu, South Korea
| | - Kea Joo Lee
- Neural Circuits Research Group, Korea Brain Research Institute, Daegu, South Korea.,Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu, South Korea
| |
Collapse
|
7
|
Slomianka L. Basic quantitative morphological methods applied to the central nervous system. J Comp Neurol 2021; 529:694-756. [PMID: 32639600 PMCID: PMC7818269 DOI: 10.1002/cne.24976] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 06/15/2020] [Accepted: 06/16/2020] [Indexed: 12/19/2022]
Abstract
Generating numbers has become an almost inevitable task associated with studies of the morphology of the nervous system. Numbers serve a desire for clarity and objectivity in the presentation of results and are a prerequisite for the statistical evaluation of experimental outcomes. Clarity, objectivity, and statistics make demands on the quality of the numbers that are not met by many methods. This review provides a refresher of problems associated with generating numbers that describe the nervous system in terms of the volumes, surfaces, lengths, and numbers of its components. An important aim is to provide comprehensible descriptions of the methods that address these problems. Collectively known as design-based stereology, these methods share two features critical to their application. First, they are firmly based in mathematics and its proofs. Second and critically underemphasized, an understanding of their mathematical background is not necessary for their informed and productive application. Understanding and applying estimators of volume, surface, length or number does not require more of an organizational mastermind than an immunohistochemical protocol. And when it comes to calculations, square roots are the gravest challenges to overcome. Sampling strategies that are combined with stereological probes are efficient and allow a rational assessment if the numbers that have been generated are "good enough." Much may be unfamiliar, but very little is difficult. These methods can no longer be scapegoats for discrepant results but faithfully produce numbers on the material that is assessed. They also faithfully reflect problems that associated with the histological material and the anatomically informed decisions needed to generate numbers that are not only valid in theory. It is within reach to generate practically useful numbers that must integrate with qualitative knowledge to understand the function of neural systems.
Collapse
Affiliation(s)
- Lutz Slomianka
- University of Zürich, Institute of AnatomyZürichSwitzerland
| |
Collapse
|
8
|
Myhre CL, Thygesen C, Villadsen B, Vollerup J, Ilkjær L, Krohn KT, Grebing M, Zhao S, Khan AM, Dissing-Olesen L, Jensen MS, Babcock AA, Finsen B. Microglia Express Insulin-Like Growth Factor-1 in the Hippocampus of Aged APP swe/PS1 ΔE9 Transgenic Mice. Front Cell Neurosci 2019; 13:308. [PMID: 31417357 PMCID: PMC6682662 DOI: 10.3389/fncel.2019.00308] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Accepted: 06/24/2019] [Indexed: 11/14/2022] Open
Abstract
Insulin-like growth factor-1 (IGF-1) is a pleiotropic molecule with neurotrophic and immunomodulatory functions. Knowing the capacity of chronically activated microglia to produce IGF-1 may therefore show essential to promote beneficial microglial functions in Alzheimer's disease (AD). Here, we investigated the expression of IGF-1 mRNA and IGF-1 along with the expression of tumor necrosis factor (TNF) mRNA, and the amyloid-β (Aβ) plaque load in the hippocampus of 3- to 24-month-old APPswe/PS1ΔE9 transgenic (Tg) and wild-type (WT) mice. As IGF-1, in particular, is implicated in neurogenesis we also monitored the proliferation of cells in the subgranular zone (sgz) of the dentate gyrus. We found that the Aβ plaque load reached its maximum in aged 21- and 24-month-old APPswe/PS1ΔE9 Tg mice, and that microglial reactivity and hippocampal IGF-1 and TNF mRNA levels were significantly elevated in aged APPswe/PS1ΔE9 Tg mice. The sgz cell proliferation decreased with age, regardless of genotype and increased IGF-1/TNF mRNA levels. Interestingly, IGF-1 mRNA was expressed in subsets of sgz cells, likely neuroblasts, and neurons in both genotypes, regardless of age, as well as in glial-like cells. By double in situ hybridization these were shown to be IGF1 mRNA+ CD11b mRNA+ cells, i.e., IGF-1 mRNA-expressing microglia. Quantification showed a 2-fold increase in the number of microglia and IGF-1 mRNA-expressing microglia in the molecular layer of the dentate gyrus in aged APPswe/PS1ΔE9 Tg mice. Double-immunofluorescence showed that IGF-1 was expressed in a subset of Aβ plaque-associated CD11b+ microglia and in several subsets of neurons. Exposure of primary murine microglia and BV2 cells to Aβ42 did not affect IGF-1 mRNA expression. IGF-1 mRNA levels remained constant in WT mice with aging, unlike TNF mRNA levels which increased with aging. In conclusion, our results suggest that the increased IGF-1 mRNA levels can be ascribed to a larger number of IGF-1 mRNA-expressing microglia in the aged APPswe/PS1ΔE9 Tg mice. The finding that subsets of microglia retain the capacity to express IGF-1 mRNA and IGF-1 in the aged APPswe/PS1ΔE9 Tg mice is encouraging, considering the beneficial therapeutic potential of modulating microglial production of IGF-1 in AD.
Collapse
Affiliation(s)
- Christa Løth Myhre
- Department of Neurobiology, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Camilla Thygesen
- Department of Neurobiology, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
- Brain Research – Inter-Disciplinary Guided Excellence, Department of Clinical Research, University of Southern Denmark, Odense, Denmark
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Birgitte Villadsen
- Department of Neurobiology, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
- Brain Research – Inter-Disciplinary Guided Excellence, Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Jeanette Vollerup
- Department of Neurobiology, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
- Brain Research – Inter-Disciplinary Guided Excellence, Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Laura Ilkjær
- Department of Neurobiology, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Katrine Tækker Krohn
- Department of Neurobiology, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
- Brain Research – Inter-Disciplinary Guided Excellence, Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Manuela Grebing
- Department of Neurobiology, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Shuainan Zhao
- Department of Neurobiology, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
- Brain Research – Inter-Disciplinary Guided Excellence, Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Asif Manzoor Khan
- Department of Neurobiology, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Lasse Dissing-Olesen
- Department of Neurobiology, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | | | - Alicia A. Babcock
- Department of Neurobiology, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Bente Finsen
- Department of Neurobiology, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
- Brain Research – Inter-Disciplinary Guided Excellence, Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| |
Collapse
|
9
|
Thygesen C, Ilkjær L, Kempf SJ, Hemdrup AL, von Linstow CU, Babcock AA, Darvesh S, Larsen MR, Finsen B. Diverse Protein Profiles in CNS Myeloid Cells and CNS Tissue From Lipopolysaccharide- and Vehicle-Injected APP SWE/PS1 ΔE9 Transgenic Mice Implicate Cathepsin Z in Alzheimer's Disease. Front Cell Neurosci 2018; 12:397. [PMID: 30459560 PMCID: PMC6232379 DOI: 10.3389/fncel.2018.00397] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Accepted: 10/15/2018] [Indexed: 12/20/2022] Open
Abstract
Neuroinflammation, characterized by chronic activation of the myeloid-derived microglia, is a hallmark of Alzheimer’s disease (AD). Systemic inflammation, typically resulting from infection, has been linked to the progression of AD due to exacerbation of the chronic microglial reaction. However, the mechanism and the consequences of this exacerbation are largely unknown. Here, we mimicked systemic inflammation in AD with weekly intraperitoneal (i.p.) injections of APPSWE/PS1ΔE9 transgenic mice with E. coli lipopolysaccharide (LPS) from 9 to 12 months of age, corresponding to the period with the steepest increase in amyloid pathology. We found that the repeated LPS injections ameliorated amyloid pathology in the neocortex while increasing the neuroinflammatory reaction. To elucidate mechanisms, we analyzed the proteome of the hippocampus from the same mice as well as in unique samples of CNS myeloid cells. The repeated LPS injections stimulated protein pathways of the complement system, retinoid receptor activation and oxidative stress. CNS myeloid cells from transgenic mice showed enrichment in pathways of amyloid-beta clearance and elevated levels of the lysosomal protease cathepsin Z, as well as amyloid precursor protein, apolipoprotein E and clusterin. These proteins were found elevated in the proteome of both LPS and vehicle injected transgenics, and co-localized to CD11b+ microglia in transgenic mice and in primary murine microglia. Additionally, cathepsin Z, amyloid precursor protein, and apolipoprotein E appeared associated with amyloid plaques in neocortex of AD cases. Interestingly, cathepsin Z was expressed in microglial-like cells and co-localized to CD68+ microglial lysosomes in AD cases, and it was expressed in perivascular cells in AD and control cases. Taken together, our results implicate systemic LPS administration in ameliorating amyloid pathology in early-to-mid stage disease in the APPSWE/PS1ΔE9 mouse and attract attention to the potential disease involvement of cathepsin Z expressed in CNS myeloid cells in AD.
Collapse
Affiliation(s)
- Camilla Thygesen
- Department of Neurobiology, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark.,Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark.,Brain Research - Inter-Disciplinary Guided Excellence, Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Laura Ilkjær
- Department of Neurobiology, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Stefan J Kempf
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Anne Louise Hemdrup
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | | | - Alicia A Babcock
- Department of Neurobiology, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Sultan Darvesh
- Department of Medicine (Neurology and Geriatric Medicine) - Department of Medical Neuroscience, Dalhousie University, Halifax, NS, Canada.,Department of Chemistry and Physics, Mount Saint Vincent University, Halifax, NS, Canada
| | - Martin R Larsen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Bente Finsen
- Department of Neurobiology, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark.,Brain Research - Inter-Disciplinary Guided Excellence, Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| |
Collapse
|
10
|
Shi Q, Chowdhury S, Ma R, Le KX, Hong S, Caldarone BJ, Stevens B, Lemere CA. Complement C3 deficiency protects against neurodegeneration in aged plaque-rich APP/PS1 mice. Sci Transl Med 2018; 9:9/392/eaaf6295. [PMID: 28566429 DOI: 10.1126/scitranslmed.aaf6295] [Citation(s) in RCA: 368] [Impact Index Per Article: 61.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2016] [Revised: 10/01/2016] [Accepted: 02/15/2017] [Indexed: 12/14/2022]
Abstract
The complement cascade not only is an innate immune response that enables removal of pathogens but also plays an important role in microglia-mediated synaptic refinement during brain development. Complement C3 is elevated in Alzheimer's disease (AD), colocalizing with neuritic plaques, and appears to contribute to clearance of Aβ by microglia in the brain. Previously, we reported that C3-deficient C57BL/6 mice were protected against age-related and region-specific loss of hippocampal synapses and cognitive decline during normal aging. Furthermore, blocking complement and downstream iC3b/CR3 signaling rescued synapses from Aβ-induced loss in young AD mice before amyloid plaques had accumulated. We assessed the effects of C3 deficiency in aged, plaque-rich APPswe/PS1dE9 transgenic mice (APP/PS1;C3 KO). We examined the effects of C3 deficiency on cognition, Aβ plaque deposition, and plaque-related neuropathology at later AD stages in these mice. We found that 16-month-old APP/PS1;C3 KO mice performed better on a learning and memory task than did APP/PS1 mice, despite having more cerebral Aβ plaques. Aged APP/PS1;C3 KO mice also had fewer microglia and astrocytes localized within the center of hippocampal Aβ plaques compared to APP/PS1 mice. Several proinflammatory cytokines in the brain were reduced in APP/PS1;C3 KO mice, consistent with an altered microglial phenotype. C3 deficiency also protected APP/PS1 mice against age-dependent loss of synapses and neurons. Our study suggests that complement C3 or downstream complement activation fragments may play an important role in Aβ plaque pathology, glial responses to plaques, and neuronal dysfunction in the brains of APP/PS1 mice.
Collapse
Affiliation(s)
- Qiaoqiao Shi
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Building for Transformative Medicine, 9th Floor, 60 Fenwood Road, Boston, MA 02115, USA.,Harvard Medical School, Boston, MA 02115, USA
| | - Saba Chowdhury
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Building for Transformative Medicine, 9th Floor, 60 Fenwood Road, Boston, MA 02115, USA
| | - Rong Ma
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Building for Transformative Medicine, 9th Floor, 60 Fenwood Road, Boston, MA 02115, USA
| | - Kevin X Le
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Building for Transformative Medicine, 9th Floor, 60 Fenwood Road, Boston, MA 02115, USA
| | - Soyon Hong
- Harvard Medical School, Boston, MA 02115, USA.,Department of Neurology, F.M. Kirby Neurobiology Center, Boston Children's Hospital, Center for Life Sciences, 12th Floor, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Barbara J Caldarone
- Harvard Medical School, Boston, MA 02115, USA.,Harvard NeuroDiscovery Center NeuroBehavior Laboratory, Department of Neurology, Brigham and Women's Hospital, Harvard Institute of Medicine, Room 945, 77 Avenue Louis Pasteur, Boston, MA 02115, USA
| | - Beth Stevens
- Harvard Medical School, Boston, MA 02115, USA.,Department of Neurology, F.M. Kirby Neurobiology Center, Boston Children's Hospital, Center for Life Sciences, 12th Floor, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Cynthia A Lemere
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Building for Transformative Medicine, 9th Floor, 60 Fenwood Road, Boston, MA 02115, USA. .,Harvard Medical School, Boston, MA 02115, USA
| |
Collapse
|
11
|
Brooks SW, Dykes AC, Schreurs BG. A High-Cholesterol Diet Increases 27-Hydroxycholesterol and Modifies Estrogen Receptor Expression and Neurodegeneration in Rabbit Hippocampus. J Alzheimers Dis 2018; 56:185-196. [PMID: 27911307 DOI: 10.3233/jad-160725] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Hypercholesterolemia has been implicated in numerous health problems from cardiovascular disease to neurodegeneration. High serum cholesterol levels in midlife have been associated with an increased risk of developing Alzheimer's disease (AD) later in life which suggests that the pathways leading to AD pathology might be activated decades before the symptoms of the disease are detected. Cholesterol-fed animals, particularly cholesterol-fed rabbits, exhibit brain pathology similar to the changes found in brains of AD patients. Dietary cholesterol, which cannot pass the blood-brain barrier, is thought to influence central nervous system homeostasis by increased transport of its circulatory breakdown product, 27-hydroxycholesterol (27-OHC), into the brain. 27-OHC is an endogenous selective estrogen receptor modulator. Estrogen-mediated non-reproductive functions require estrogen receptors (ERs) and include modulation of mitochondrial function and structure, as well as regulation of synaptogenesis in the brain. ERs are located in brain areas affected early in AD pathogenesis, including the hippocampus. Here we report that increase in serum cholesterol, induced by feeding rabbits a high-cholesterol diet, is associated with higher levels of 27-OHC in the brain as well as increased levels of neurodegeneration in the hippocampus. Furthermore, these results are accompanied by changes in expression of ERs in the hippocampus as well as a decrease in hippocampal mitochondria. These findings provide an important insight into one of the possible mechanisms involved in the development of AD, and shed light on the processes that may antedate amyloid-β and tau phosphorylation changes currently hypothesized to cause AD symptomology and pathology.
Collapse
Affiliation(s)
- Sylwia W Brooks
- School of Medicine, West Virginia University, Morgantown, WV, USA.,Blanchette Rockefeller Neurosciences Institute, Morgantown, WV, USA
| | - Ava C Dykes
- Molecular Biology Core Facility, Centers for Disease Control and Prevention/National Institute for Occupational Safety and Health, Morgantown, WV, USA
| | - Bernard G Schreurs
- School of Medicine, West Virginia University, Morgantown, WV, USA.,Blanchette Rockefeller Neurosciences Institute, Morgantown, WV, USA
| |
Collapse
|
12
|
Neuron and neuroblast numbers and cytogenesis in the dentate gyrus of aged APP swe /PS1 dE9 transgenic mice: Effect of long-term treatment with paroxetine. Neurobiol Dis 2017; 104:50-60. [DOI: 10.1016/j.nbd.2017.04.021] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2016] [Revised: 04/07/2017] [Accepted: 04/27/2017] [Indexed: 11/20/2022] Open
|
13
|
Stuart KE, King AE, Fernandez-Martos CM, Dittmann J, Summers MJ, Vickers JC. Mid-life environmental enrichment increases synaptic density in CA1 in a mouse model of Aβ-associated pathology and positively influences synaptic and cognitive health in healthy ageing. J Comp Neurol 2017; 525:1797-1810. [DOI: 10.1002/cne.24156] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2016] [Revised: 11/09/2016] [Accepted: 11/10/2016] [Indexed: 12/22/2022]
Affiliation(s)
- Kimberley E. Stuart
- Faculty of Health; Wicking Dementia Research and Education Centre, University of Tasmania; Tasmania Australia
| | - Anna E. King
- Faculty of Health; Wicking Dementia Research and Education Centre, University of Tasmania; Tasmania Australia
| | - Carmen M. Fernandez-Martos
- Faculty of Health; Wicking Dementia Research and Education Centre, University of Tasmania; Tasmania Australia
| | - Justin Dittmann
- Faculty of Health; Wicking Dementia Research and Education Centre, University of Tasmania; Tasmania Australia
| | - Mathew J. Summers
- Faculty of Health; Wicking Dementia Research and Education Centre, University of Tasmania; Tasmania Australia
- School of Social Sciences; University of the Sunshine Coast; Sippy Downs Queensland Australia
| | - James C. Vickers
- Faculty of Health; Wicking Dementia Research and Education Centre, University of Tasmania; Tasmania Australia
| |
Collapse
|
14
|
Zhang C, Kuo CC, Moghadam SH, Monte L, Campbell SN, Rice KC, Sawchenko PE, Masliah E, Rissman RA. Corticotropin-releasing factor receptor-1 antagonism mitigates beta amyloid pathology and cognitive and synaptic deficits in a mouse model of Alzheimer's disease. Alzheimers Dement 2016; 12:527-37. [PMID: 26555315 PMCID: PMC4860182 DOI: 10.1016/j.jalz.2015.09.007] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Revised: 09/27/2015] [Accepted: 09/28/2015] [Indexed: 11/24/2022]
Abstract
INTRODUCTION Stress and corticotropin-releasing factor (CRF) have been implicated as mechanistically involved in Alzheimer's disease (AD), but agents that impact CRF signaling have not been carefully tested for therapeutic efficacy or long-term safety in animal models. METHODS To test whether antagonism of the type-1 corticotropin-releasing factor receptor (CRFR1) could be used as a disease-modifying treatment for AD, we used a preclinical prevention paradigm and treated 30-day-old AD transgenic mice with the small-molecule, CRFR1-selective antagonist, R121919, for 5 months, and examined AD pathologic and behavioral end points. RESULTS R121919 significantly prevented the onset of cognitive impairment in female mice and reduced cellular and synaptic deficits and beta amyloid and C-terminal fragment-β levels in both genders. We observed no tolerability or toxicity issues in mice treated with R121919. DISCUSSION CRFR1 antagonism presents a viable disease-modifying therapy for AD, recommending its advancement to early-phase human safety trials.
Collapse
Affiliation(s)
- Cheng Zhang
- Department of Neurosciences, University of California San Diego, La Jolla, CA, USA
| | - Ching-Chang Kuo
- NeuroInformatics Center, University of Oregon, Eugene, OR, USA
| | - Setareh H Moghadam
- Department of Neurosciences, University of California San Diego, La Jolla, CA, USA
| | - Louise Monte
- Department of Neurosciences, University of California San Diego, La Jolla, CA, USA
| | - Shannon N Campbell
- Department of Neurosciences, University of California San Diego, La Jolla, CA, USA
| | - Kenner C Rice
- Chemical Biology Research Branch, National Institute on Drug Abuse and Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA
| | | | - Eliezer Masliah
- Department of Neurosciences, University of California San Diego, La Jolla, CA, USA; Department of Pathology, University of California San Diego, La Jolla, CA, USA
| | - Robert A Rissman
- Department of Neurosciences, University of California San Diego, La Jolla, CA, USA.
| |
Collapse
|
15
|
Jiao X, Beck KD, Myers CE, Servatius RJ, Pang KCH. Altered activity of the medial prefrontal cortex and amygdala during acquisition and extinction of an active avoidance task. Front Behav Neurosci 2015; 9:249. [PMID: 26441578 PMCID: PMC4569748 DOI: 10.3389/fnbeh.2015.00249] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 08/27/2015] [Indexed: 11/25/2022] Open
Abstract
Altered medial prefrontal cortex (mPFC) and amygdala function is associated with anxiety-related disorders. While the mPFC-amygdala pathway has a clear role in fear conditioning, these structures are also involved in active avoidance. Given that avoidance perseveration represents a core symptom of anxiety disorders, the neural substrate of avoidance, especially its extinction, requires better understanding. The present study was designed to investigate the activity, particularly, inhibitory neuronal activity in mPFC and amygdala during acquisition and extinction of lever-press avoidance in rats. Neural activity was examined in the mPFC, intercalated cell clusters (ITCs) lateral (LA), basal (BA) and central (CeA) amygdala, at various time points during acquisition and extinction, using induction of the immediate early gene product, c-Fos. Neural activity was greater in the mPFC, LA, BA, and ITC during the extinction phase as compared to the acquisition phase. In contrast, the CeA was the only region that was more activated during acquisition than during extinction. Our results indicate inhibitory neurons are more activated during late phase of acquisition and extinction in the mPFC and LA, suggesting the dynamic involvement of inhibitory circuits in the development and extinction of avoidance response. Together, these data start to identify the key brain regions important in active avoidance behavior, areas that could be associated with avoidance perseveration in anxiety disorders.
Collapse
Affiliation(s)
- Xilu Jiao
- Neurobehavioral Laboratory, Veterans Bio-Medical Research Institute (VBRI) East Orange, NJ, USA
| | - Kevin D Beck
- Neurobehavioral Research Laboratory, Department of Veterans Affairs, New Jersey Health Care System East Orange, NJ, USA ; Department of Pharmacology, Physiology and Neuroscience, Rutgers Biomedical Health Sciences Newark, NJ, USA
| | - Catherine E Myers
- Neurobehavioral Research Laboratory, Department of Veterans Affairs, New Jersey Health Care System East Orange, NJ, USA ; Department of Pharmacology, Physiology and Neuroscience, Rutgers Biomedical Health Sciences Newark, NJ, USA
| | - Richard J Servatius
- Department of Pharmacology, Physiology and Neuroscience, Rutgers Biomedical Health Sciences Newark, NJ, USA ; Syracuse VA Medical Center, Department of Veterans Affairs Syracuse, NY, USA
| | - Kevin C H Pang
- Neurobehavioral Research Laboratory, Department of Veterans Affairs, New Jersey Health Care System East Orange, NJ, USA ; Department of Pharmacology, Physiology and Neuroscience, Rutgers Biomedical Health Sciences Newark, NJ, USA
| |
Collapse
|
16
|
Nikolajsen GN, Kotynski KA, Jensen MS, West MJ. Quantitative analysis of the capillary network of aged APPswe/PS1dE9 transgenic mice. Neurobiol Aging 2015; 36:2954-2962. [PMID: 26364735 DOI: 10.1016/j.neurobiolaging.2015.08.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Revised: 08/04/2015] [Accepted: 08/06/2015] [Indexed: 11/26/2022]
Abstract
A combination of immunohistochemical and stereological techniques were used to investigate the capillary network in the cerebral cortex of 18-month-old APPswe/PS1dE9 transgenic (Tg) mice and control littermates. Data regarding total capillary length, segment number, diffusion radius, and pericyte number are presented. The total length was 60 meters and there was a one-to-one relationship between the number of capillary segments and pericytes in both groups. Significant differences were not observed in the Tg and wild-type controls indicating that the Alzheimer's-like amyloidosis produced in this Tg mouse has a minimal affect on the structural integrity of the cerebral capillary network.
Collapse
Affiliation(s)
| | | | | | - Mark J West
- Department of Biomedicine, Aarhus University, Aarhus C, Denmark
| |
Collapse
|
17
|
Babcock AA, Ilkjær L, Clausen BH, Villadsen B, Dissing-Olesen L, Bendixen ATM, Lyck L, Lambertsen KL, Finsen B. Cytokine-producing microglia have an altered beta-amyloid load in aged APP/PS1 Tg mice. Brain Behav Immun 2015; 48:86-101. [PMID: 25774009 DOI: 10.1016/j.bbi.2015.03.006] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Revised: 02/21/2015] [Accepted: 03/06/2015] [Indexed: 12/17/2022] Open
Abstract
Beta-amyloid (Aβ) plaques and chronic neuroinflammation are significant neuropathological features of Alzheimer's disease. Microglial cells in aged brains have potential to produce cytokines such as TNF and IL-1 family members (IL-1α, IL-1β, and IL-1Ra) and to phagocytose Aβ in Alzheimer's disease, however the inter-relationship between these processes is poorly understood. Here we show that % Aβ plaque load followed a sigmoidal trajectory with age in the neocortex of APPswe/PS1ΔE9 Tg mice, and correlated positively with soluble Aβ40 and Aβ42. Aβ measures were moderately correlated with mRNA levels of CD11b, TNF, and IL-1Ra. Cytokine production and Aβ load were assessed in neocortical CD11b(+)(CD45(+)) microglia by flow cytometry. Whereas most microglia in aged mice produced IL-1Ra, relatively low proportions of microglia produced TNF, IL-1α, and IL-1β. However, microglial production of these latter cytokines was generally increased in APP/PS1 Tg mice. Microglia that phagocytosed endogenously-produced Aβ were only observed in APP/PS1 Tg mice. Differences in phagocytic index and total Aβ load were observed in microglia with specific cytokine profiles. Both phagocytic index and total Aβ load were higher in IL-1α(+) and IL-1Ra(+) microglia, than microglia that did not produce these cytokines. In contrast, total Aβ load was lower in IL-1β(+) and TNF(+) microglia, compared to IL-1β(-) and TNF(-) microglia, and TNF(+) microglia also had a lower phagocytic index. Using GFP bone marrow chimeric mice, we confirmed that the majority of neocortical CD11b(+)(CD45(+)) microglia were resident cells (GFP(-)) in APP/PS1 Tg mice, even after selectively analysing CD11b(+)CD45(high) cells, which are typically considered to be infiltrating cells. Together, our data demonstrate that cytokine expression is selectively correlated with age and Aβ pathology, and is associated with an altered Aβ load in phagocytic microglia from APP/PS1 Tg mice. These findings have implications for understanding the regulation of microglial cytokine production and phagocytosis of Aβ in Alzheimer's disease.
Collapse
Affiliation(s)
- Alicia A Babcock
- Institute of Molecular Medicine, University of Southern Denmark, JB Winsløws Vej 25, 2, 5000 Odense C, Denmark.
| | - Laura Ilkjær
- Institute of Molecular Medicine, University of Southern Denmark, JB Winsløws Vej 25, 2, 5000 Odense C, Denmark.
| | - Bettina H Clausen
- Institute of Molecular Medicine, University of Southern Denmark, JB Winsløws Vej 25, 2, 5000 Odense C, Denmark.
| | - Birgitte Villadsen
- Institute of Molecular Medicine, University of Southern Denmark, JB Winsløws Vej 25, 2, 5000 Odense C, Denmark.
| | - Lasse Dissing-Olesen
- Institute of Molecular Medicine, University of Southern Denmark, JB Winsløws Vej 25, 2, 5000 Odense C, Denmark.
| | - Anita T M Bendixen
- Institute of Molecular Medicine, University of Southern Denmark, JB Winsløws Vej 25, 2, 5000 Odense C, Denmark.
| | - Lise Lyck
- Institute of Molecular Medicine, University of Southern Denmark, JB Winsløws Vej 25, 2, 5000 Odense C, Denmark.
| | - Kate L Lambertsen
- Institute of Molecular Medicine, University of Southern Denmark, JB Winsløws Vej 25, 2, 5000 Odense C, Denmark.
| | - Bente Finsen
- Institute of Molecular Medicine, University of Southern Denmark, JB Winsløws Vej 25, 2, 5000 Odense C, Denmark.
| |
Collapse
|
18
|
Wang DB, Kinoshita Y, Kinoshita C, Uo T, Sopher BL, Cudaback E, Keene CD, Bilousova T, Gylys K, Case A, Jayadev S, Wang HG, Garden GA, Morrison RS. Loss of endophilin-B1 exacerbates Alzheimer's disease pathology. Brain 2015; 138:2005-19. [PMID: 25981964 DOI: 10.1093/brain/awv128] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Accepted: 03/15/2015] [Indexed: 12/31/2022] Open
Abstract
Endophilin-B1, also known as Bax-interacting factor 1 (Bif-1, and encoded by SH3GLB1), is a multifunctional protein involved in apoptosis, autophagy and mitochondrial function. We recently described a unique neuroprotective role for neuron-specific alternatively spliced isoforms of endophilin-B1. To examine whether endophilin-B1-mediated neuroprotection could be a novel therapeutic target for Alzheimer's disease we used a double mutant amyloid precursor protein and presenilin 1 (APPswe/PSEN1dE9) mouse model of Alzheimer's disease and observed that expression of neuron-specific endophilin-B1 isoforms declined with disease progression. To determine if this reduction in endophilin-B1 has a functional role in Alzheimer's disease pathogenesis, we crossed endophilin-B1(-/-) mice with APPswe/PSEN1dE9 mice. Deletion of endophilin-B1 accelerated disease onset and progression in 6-month-old APPswe/PSEN1dE9/endophilin-B1(-/-) mice, which showed more plaques, astrogliosis, synaptic degeneration, cognitive impairment and mortality than APPswe/PSEN1dE9 mice. In mouse primary cortical neuron cultures, overexpression of neuron-specific endophilin-B1 isoforms protected against amyloid-β-induced apoptosis and mitochondrial dysfunction. Additionally, protein and mRNA levels of neuron-specific endophilin-B1 isoforms were also selectively decreased in the cerebral cortex and in the synaptic compartment of patients with Alzheimer's disease. Flow sorting of synaptosomes from patients with Alzheimer's disease demonstrated a negative correlation between amyloid-β and endophilin-B1 levels. The importance of endophilin-B1 in neuronal function was further underscored by the development of synaptic degeneration and cognitive and motor impairment in endophilin-B1(-/-) mice by 12 months. Our findings suggest that endophilin-B1 is a key mediator of a feed-forward mechanism of Alzheimer's disease pathogenesis where amyloid-β reduces neuron-specific endophilin-B1, which in turn enhances amyloid-β accumulation and neuronal vulnerability to stress.
Collapse
Affiliation(s)
- David B Wang
- 1 Department of Neurological Surgery, University of Washington School of Medicine, Seattle, WA 98195-6470, USA
| | - Yoshito Kinoshita
- 1 Department of Neurological Surgery, University of Washington School of Medicine, Seattle, WA 98195-6470, USA
| | - Chizuru Kinoshita
- 1 Department of Neurological Surgery, University of Washington School of Medicine, Seattle, WA 98195-6470, USA
| | - Takuma Uo
- 1 Department of Neurological Surgery, University of Washington School of Medicine, Seattle, WA 98195-6470, USA
| | - Bryce L Sopher
- 2 Department of Neurology, University of Washington School of Medicine, Seattle, WA 98195-6470, USA
| | - Eiron Cudaback
- 3 Department of Pathology, University of Washington School of Medicine, Seattle, WA 98195-6470, USA
| | - C Dirk Keene
- 3 Department of Pathology, University of Washington School of Medicine, Seattle, WA 98195-6470, USA
| | - Tina Bilousova
- 4 School of Nursing, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Karen Gylys
- 4 School of Nursing, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Amanda Case
- 2 Department of Neurology, University of Washington School of Medicine, Seattle, WA 98195-6470, USA
| | - Suman Jayadev
- 2 Department of Neurology, University of Washington School of Medicine, Seattle, WA 98195-6470, USA
| | - Hong-Gang Wang
- 5 Department of Pediatrics, The Pennsylvania State University College of Medicine, Hershey, PA 1703, USA
| | - Gwenn A Garden
- 2 Department of Neurology, University of Washington School of Medicine, Seattle, WA 98195-6470, USA 3 Department of Pathology, University of Washington School of Medicine, Seattle, WA 98195-6470, USA
| | - Richard S Morrison
- 1 Department of Neurological Surgery, University of Washington School of Medicine, Seattle, WA 98195-6470, USA
| |
Collapse
|
19
|
Sala-Llonch R, Lladó A, Fortea J, Bosch B, Antonell A, Balasa M, Bargalló N, Bartrés-Faz D, Molinuevo JL, Sánchez-Valle R. Evolving brain structural changes in PSEN1 mutation carriers. Neurobiol Aging 2014; 36:1261-70. [PMID: 25638532 DOI: 10.1016/j.neurobiolaging.2014.12.022] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Revised: 12/16/2014] [Accepted: 12/17/2014] [Indexed: 02/04/2023]
Abstract
Familial Alzheimer's disease provides the opportunity to investigate brain changes even before the symptoms onset. We performed a structural magnetic resonance imaging (MRI) study in 38 participants from families with presenilin 1 gene mutations: 11 symptomatic mutation carriers, 13 asymptomatic mutation carriers (AMC), with a mean of 16.22 years before the estimated appearance of symptoms, and 14 noncarriers. A subset of subjects was studied longitudinally 2 and 4 years after the first scan. We found decreased cortical thickness (CTh) and volume in cortical and subcortical structures in symptomatic mutation carriers, with progressive loss over time. In AMC, we found increased CTh and volume in temporoparietal regions and in precuneus-posterior cingulate compared with controls at baseline. Longitudinal studies in AMC, by contrast, showed accelerated rates of CTh loss in precuneus-posterior cingulate and superior parietal, right lateral temporal and left orbitofrontal, and middle frontal regions. These findings suggest that brain structure in presenilin 1 mutation carriers follows nonlinear trajectories, with regional increases during the very early presymptomatic period. Initial neuroinflammation and/or accumulation of amyloid species followed by neurodegeneration, or congenital morphometric differences, may explain the observed features.
Collapse
Affiliation(s)
- Roser Sala-Llonch
- Department of Psychiatry and Clinical Psychobiology, Universitat de Barcelona, Barcelona, Spain; Institut d'Investigació Biomèdica August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Albert Lladó
- Institut d'Investigació Biomèdica August Pi i Sunyer (IDIBAPS), Barcelona, Spain; Alzheimer's Disease and Other Cognitive Disorders Unit, Department of Neurology, Hospital Clínic, Barcelona, Spain
| | - Juan Fortea
- Memory Unit, Department of Neurology, Hospital de Sant Pau, Barcelona, Spain
| | - Beatriz Bosch
- Institut d'Investigació Biomèdica August Pi i Sunyer (IDIBAPS), Barcelona, Spain; Alzheimer's Disease and Other Cognitive Disorders Unit, Department of Neurology, Hospital Clínic, Barcelona, Spain
| | - Anna Antonell
- Institut d'Investigació Biomèdica August Pi i Sunyer (IDIBAPS), Barcelona, Spain; Alzheimer's Disease and Other Cognitive Disorders Unit, Department of Neurology, Hospital Clínic, Barcelona, Spain
| | - Mircea Balasa
- Institut d'Investigació Biomèdica August Pi i Sunyer (IDIBAPS), Barcelona, Spain; Alzheimer's Disease and Other Cognitive Disorders Unit, Department of Neurology, Hospital Clínic, Barcelona, Spain
| | - Nuria Bargalló
- Institut d'Investigació Biomèdica August Pi i Sunyer (IDIBAPS), Barcelona, Spain; Department of Radiology, Hospital Clínic, Barcelona, Spain
| | - David Bartrés-Faz
- Department of Psychiatry and Clinical Psychobiology, Universitat de Barcelona, Barcelona, Spain; Institut d'Investigació Biomèdica August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - José Luis Molinuevo
- Institut d'Investigació Biomèdica August Pi i Sunyer (IDIBAPS), Barcelona, Spain; Alzheimer's Disease and Other Cognitive Disorders Unit, Department of Neurology, Hospital Clínic, Barcelona, Spain
| | - Raquel Sánchez-Valle
- Institut d'Investigació Biomèdica August Pi i Sunyer (IDIBAPS), Barcelona, Spain; Alzheimer's Disease and Other Cognitive Disorders Unit, Department of Neurology, Hospital Clínic, Barcelona, Spain.
| |
Collapse
|
20
|
Neuman KM, Molina-Campos E, Musial TF, Price AL, Oh KJ, Wolke ML, Buss EW, Scheff SW, Mufson EJ, Nicholson DA. Evidence for Alzheimer's disease-linked synapse loss and compensation in mouse and human hippocampal CA1 pyramidal neurons. Brain Struct Funct 2014; 220:3143-65. [PMID: 25031178 DOI: 10.1007/s00429-014-0848-z] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2013] [Accepted: 07/09/2014] [Indexed: 12/17/2022]
Abstract
Alzheimer's disease (AD) is associated with alterations in the distribution, number, and size of inputs to hippocampal neurons. Some of these changes are thought to be neurodegenerative, whereas others are conceptualized as compensatory, plasticity-like responses, wherein the remaining inputs reactively innervate vulnerable dendritic regions. Here, we provide evidence that the axospinous synapses of human AD cases and mice harboring AD-linked genetic mutations (the 5XFAD line) exhibit both, in the form of synapse loss and compensatory changes in the synapses that remain. Using array tomography, quantitative conventional electron microscopy, immunogold electron microscopy for AMPARs, and whole-cell patch-clamp physiology, we find that hippocampal CA1 pyramidal neurons in transgenic mice are host to an age-related synapse loss in their distal dendrites, and that the remaining synapses express more AMPA-type glutamate receptors. Moreover, the number of axonal boutons that synapse with multiple spines is significantly reduced in the transgenic mice. Through serial section electron microscopic analyses of human hippocampal tissue, we further show that putative compensatory changes in synapse strength are also detectable in axospinous synapses of proximal and distal dendrites in human AD cases, and that their multiple synapse boutons may be more powerful than those in non-cognitively impaired human cases. Such findings are consistent with the notion that the pathophysiology of AD is a multivariate product of both neurodegenerative and neuroplastic processes, which may produce adaptive and/or maladaptive responses in hippocampal synaptic strength and plasticity.
Collapse
Affiliation(s)
- Krystina M Neuman
- Department of Neurological Sciences, Rush University Medical Center, 1653 West Harrison Street, Chicago, IL, 60612, USA
| | - Elizabeth Molina-Campos
- Department of Neurological Sciences, Rush University Medical Center, 1653 West Harrison Street, Chicago, IL, 60612, USA
| | - Timothy F Musial
- Department of Neurological Sciences, Rush University Medical Center, 1653 West Harrison Street, Chicago, IL, 60612, USA
| | - Andrea L Price
- Department of Neurological Sciences, Rush University Medical Center, 1653 West Harrison Street, Chicago, IL, 60612, USA
| | - Kwang-Jin Oh
- Department of Neurological Sciences, Rush University Medical Center, 1653 West Harrison Street, Chicago, IL, 60612, USA
| | - Malerie L Wolke
- Department of Neurological Sciences, Rush University Medical Center, 1653 West Harrison Street, Chicago, IL, 60612, USA
| | - Eric W Buss
- Department of Neurological Sciences, Rush University Medical Center, 1653 West Harrison Street, Chicago, IL, 60612, USA
| | - Stephen W Scheff
- Sanders Brown Center on Aging, University of Kentucky, Lexington, KY, 40536, USA
| | - Elliott J Mufson
- Department of Neurological Sciences, Rush University Medical Center, 1653 West Harrison Street, Chicago, IL, 60612, USA
| | - Daniel A Nicholson
- Department of Neurological Sciences, Rush University Medical Center, 1653 West Harrison Street, Chicago, IL, 60612, USA.
| |
Collapse
|
21
|
Fortea J, Vilaplana E, Alcolea D, Carmona-Iragui M, Sánchez-Saudinos MB, Sala I, Antón-Aguirre S, González S, Medrano S, Pegueroles J, Morenas E, Clarimón J, Blesa R, Lleó A. Cerebrospinal fluid β-amyloid and phospho-tau biomarker interactions affecting brain structure in preclinical Alzheimer disease. Ann Neurol 2014; 76:223-30. [PMID: 24852682 DOI: 10.1002/ana.24186] [Citation(s) in RCA: 101] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Revised: 05/19/2014] [Accepted: 05/19/2014] [Indexed: 11/08/2022]
Abstract
OBJECTIVE To assess the relationships between core cerebrospinal fluid (CSF) biomarkers and cortical thickness (CTh) in preclinical Alzheimer disease (AD). METHODS In this cross-sectional study, normal controls (n = 145) from the Alzheimer's Disease Neuroimaging Initiative underwent structural 3T magnetic resonance imaging (MRI) and lumbar puncture. CSF β-amyloid1-42 (Aβ) and phospho-tau₁₈₁p (p-tau) levels were measured by Luminex assays. Samples were dichotomized using published cutoffs (Aβ(+) /Aβ(-) and p-tau(+) /ptau(-)). CTh was measured by Freesurfer. CTh difference maps were derived from interaction and correlation analyses. Clusters from the interaction analysis were isolated to analyze the directionality of the interaction by analysis of covariance. RESULTS We found a significant biomarker interaction between CSF Aβ and CSF p-tau levels affecting brain structure. Cortical atrophy only occurs in subjects with both Aβ(+) and p-tau(+). The stratified correlation analyses showed that the relationship between p-tau and CTh is modified by Aβ status and the relationship between Aβ and CTh is modified by p-tau status. p-Tau-dependent thinning was found in different cortical regions in Aβ(+) subjects but not in Aβ(-) subjects. Cortical thickening was related to decreasing CSF Aβ values in the absence of abnormal p-tau, but no correlations were found in p-tau(+) subjects. INTERPRETATION Our data suggest that interactions between biomarkers in AD result in a 2-phase phenomenon of pathological cortical thickening associated with low CSF Aβ, followed by atrophy once CSF p-tau becomes abnormal. These interactions should be considered in clinical trials in preclinical AD, both when selecting patients and when using MRI as a surrogate marker of efficacy.
Collapse
Affiliation(s)
- Juan Fortea
- Memory Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau - Biomedical Research Institute Sant Pau - Universitat Autònoma de Barcelona; Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas - CIBERNED
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
22
|
Drachman DA. The amyloid hypothesis, time to move on: Amyloid is the downstream result, not cause, of Alzheimer's disease. Alzheimers Dement 2014; 10:372-80. [PMID: 24589433 DOI: 10.1016/j.jalz.2013.11.003] [Citation(s) in RCA: 168] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Revised: 11/07/2013] [Accepted: 11/25/2013] [Indexed: 12/12/2022]
Abstract
The "amyloid hypothesis" has dominated Alzheimer research for more than 20 years, and proposes that amyloid is the toxic cause of neural/synaptic damage and dementia. If correct, decreasing the formation or removing amyloid should be therapeutic. Despite discrepancies in the proposed mechanism, and failed clinical trials, amyloid continues to be considered the cause of a degenerative cascade. Alternative hypotheses must explain three features: (i) why amyloid toxicity is not the etiology of Alzheimer's disease (AD), (ii) what alternative mechanisms cause the degeneration and dementia of AD, and (iii) why increased amyloid accumulates in the brain in AD. We propose that AD, which occurs in elderly, already vulnerable brains, with multiple age-related changes, is precipitated by impaired microvascular function, resulting primarily from decreased Notch-related angiogenesis. With impaired microvasculature, a lack of vascular endothelial-derived trophic factors and decreased cerebral blood flow cause the atrophy of neural structures. Therapeutic strategies should focus on supporting normal angiogenesis.
Collapse
|
23
|
Sierksma A, van den Hove D, Pfau F, Philippens M, Bruno O, Fedele E, Ricciarelli R, Steinbusch H, Vanmierlo T, Prickaerts J. Improvement of spatial memory function in APPswe/PS1dE9 mice after chronic inhibition of phosphodiesterase type 4D. Neuropharmacology 2014; 77:120-30. [DOI: 10.1016/j.neuropharm.2013.09.015] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Revised: 08/21/2013] [Accepted: 09/09/2013] [Indexed: 11/30/2022]
|
24
|
West MJ. Counting and measuring ultrastructural features of biological samples. Cold Spring Harb Protoc 2013; 2013:593-605. [PMID: 23818664 DOI: 10.1101/pdb.top071886] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Ultrastructural features of cells can be fractions of a micrometer in diameter, and electron microscopy is needed to resolve them to a degree that is compatible with stereological techniques. Because the focal depth of transmission electron microscopy (TEM) images is thousands of times greater than the thickness of the sections used with TEM, virtual sectioning of sections suitable for TEM is not possible, as it is with light microscopy and the optical disector probe. With features the size of neuronal synapses, for example, this necessitates the use of physical sections and physical disectors. Regardless of how the imaging is performed, the design of stereological studies for quantifying ultrastructural features will be essentially the same as that used in the example described here, which uses physically separated ultrathin sections viewed with conventional TEM to estimate the number and size of synapses in a particular brain region.
Collapse
|
25
|
Brasnjevic I, Lardenoije R, Schmitz C, Van Der Kolk N, Dickstein DL, Takahashi H, Hof PR, Steinbusch HW, Rutten BP. REGION-SPECIFIC NEURON AND SYNAPSE LOSS IN THE HIPPOCAMPUS OF APP SL/PS1 KNOCK-IN MICE. Transl Neurosci 2013; 4:8-19. [PMID: 24829793 PMCID: PMC4018205 DOI: 10.2478/s13380-013-0111-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Transgenic mouse models with knock-in (KI) expression of human mutant amyloid precursor protein (APP) and/or human presenilin 1 (PS1) may be helpful to elucidate the cellular consequences of APP and PS1 misprocessing in the aging brain. Age-related alterations in total numbers of neurons and in numbers of synaptophysin-immunoreactive presynaptic boutons (SIPB), as well as the amyloid plaque load were analyzed in the hippocampal dentate gyrus (DG), CA3, and CA1-2 of 2- and 10-month-old APPSL/PS1 homozygous KI, APPSL (expressing human mutant APP751 carrying the Swedish [K670N/M671L] and London [V717I] mutations under Thy-1 promoter), and PS1 homozygous KI mice (expressing human PS1 mutations [M233T and L235P]). APPSL/PS1 homozygous KI mice, but neither APPSL mice nor PS1 homozygous KI mice, showed substantial age-related loss of neurons (-47.2%) and SIPB (-22.6%), specifically in CA1-2. PS1 homozygous KI mice showed an age-related increase in hippocampal granule cell numbers (+37.9%). Loss of neurons and SIPB greatly exceeded the amount of local extracellular Aβ aggregation and astrocytes, whereas region-specific accumulation of intraneuronal Aβ preceded neuron and synapse loss. An age-related increase in the ratio of SIPB to neuron numbers in CA1-2 of APPSL/PS1 homozygous KI mice was suggestive of compensatory synaptic plasticity. These findings indicate a region-selectivity in intra- and extraneuronal Aβ accumulation in connection with neuron and synapse loss in the hippocampus of APPSL/PS1 homozygous KI mice.
Collapse
Affiliation(s)
- Ivona Brasnjevic
- Department of Psychiatry and Neuropsychology, Maastricht University, 6200 MD Maastricht, The Netherlands
- European Graduate School of Neuroscience (EURON), 6200 MD Maastricht, The Netherlands
| | - Roy Lardenoije
- Department of Psychiatry and Neuropsychology, Maastricht University, 6200 MD Maastricht, The Netherlands
| | - Christoph Schmitz
- Department of Anatomy II, Institute of Anatomy, Ludwig-Maximilians-University, 80336 Munich, Germany
| | - Nicolien Van Der Kolk
- Department of Psychiatry and Neuropsychology, Maastricht University, 6200 MD Maastricht, The Netherlands
- European Graduate School of Neuroscience (EURON), 6200 MD Maastricht, The Netherlands
| | - Dara L. Dickstein
- Fishberg Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Hisaaki Takahashi
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, 791-0295 Ehime, Japan
| | - Patrick R. Hof
- Fishberg Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Harry W.M. Steinbusch
- Department of Psychiatry and Neuropsychology, Maastricht University, 6200 MD Maastricht, The Netherlands
- European Graduate School of Neuroscience (EURON), 6200 MD Maastricht, The Netherlands
| | - Bart P.F. Rutten
- Department of Psychiatry and Neuropsychology, Maastricht University, 6200 MD Maastricht, The Netherlands
- European Graduate School of Neuroscience (EURON), 6200 MD Maastricht, The Netherlands
| |
Collapse
|
26
|
Abstract
Stereological estimates of surface have led to important insights into normal and pathological processes. This article describes the process of estimating surface area in biological structures. It includes a discussion of relationship equations for estimating surface and procedures for estimating surface area of components of organ systems. It also provides an example of estimation of the area of the pial surface of the human brain.
Collapse
|
27
|
Manaye KF, Mouton PR, Xu G, Drew A, Lei DL, Sharma Y, Rebeck GW, Turner S. Age-related loss of noradrenergic neurons in the brains of triple transgenic mice. AGE (DORDRECHT, NETHERLANDS) 2013; 35:139-147. [PMID: 22127507 PMCID: PMC3543748 DOI: 10.1007/s11357-011-9343-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2011] [Accepted: 11/07/2011] [Indexed: 05/31/2023]
Abstract
Microscopic findings in Alzheimer's disease (AD) at autopsy include a wide cortical distribution of beta amyloid (Aβ)-containing plaques and diminished numbers of pyramidal neurons in CA1 of hippocampus and tyrosine hydroxylase-positive (TH+) neurons in the locus coeruleus (LC). To better understand the neuropathology underlying cognitive decline in AD, we analyzed the AD-type neuropathology in brains of triple transgenic (3×Tg) mice harboring mutations for APP(swe), PS1(M146V), and tau(P301L). Histochemical and immunohistochemical staining and computerized stereology were carried out in age-matched young, early middle age, and late middle age 3×Tg mice. The 3×Tg mice showed an intracellular Aβ deposition in subiculum and CA1 pyramidal neurons and an extracellular distribution of amyloid plaques specifically in the subiculum of hippocampal formation and in neocortical layer V. The 3×Tg mice also showed an age-related loss of TH+ neurons in LC, with a loss of 37% of these neurons at 15 months of age. There was no loss of CA1 neurons at any age examined. Reduced AD-type neuropathology in CA1 of 3×Tg mice suggests a possible neuroprotective role for high intracellular-to-extracellular ratios of insoluble Aβ deposits. Understanding the neurobiology of this apparent neuroprotection could lead to an improved understanding of age-related cognitive function in general, and the development of novel strategies for the therapeutic management of AD patients.
Collapse
Affiliation(s)
- Kebreten F Manaye
- Department of Physiology and Biophysics, College of Medicine, Howard University, 520 W St. NW, Washington, DC 20059, USA.
| | | | | | | | | | | | | | | |
Collapse
|
28
|
Sierksma ASR, Rutten K, Sydlik S, Rostamian S, Steinbusch HWM, van den Hove DLA, Prickaerts J. Chronic phosphodiesterase type 2 inhibition improves memory in the APPswe/PS1dE9 mouse model of Alzheimer's disease. Neuropharmacology 2012; 64:124-36. [PMID: 22771768 DOI: 10.1016/j.neuropharm.2012.06.048] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2012] [Revised: 06/22/2012] [Accepted: 06/24/2012] [Indexed: 01/08/2023]
Abstract
Alzheimer's disease (AD) is characterized by progressive cognitive deficits and synaptic dysfunction. Over the last decade phosphodiesterase inhibitors (PDEIs) have received increasing attention as putative cognition enhancers and have been suggested as a novel treatment strategy for AD. Given their ability to prevent hydrolysis of cAMP and/or cGMP, they can stimulate the cAMP/protein kinase A (PKA)/cAMP element-binding protein (CREB) and cGMP/PKG/CREB pathway to enhance synaptic transmission by increasing CREB phosphorylation (pCREB) and brain-derived neurotrophic factor (BDNF) transcription. Based on previous research, we hypothesized that chronic PDE2I treatment would improve AD-related cognitive deficits, by decreasing amyloid-β (Aβ) plaque load, enhancing pCREB and BDNF levels and increasing synaptic density in the hippocampus of 8-month-old APPswe/PS1dE9 mice. Results indicated that chronic PDE2I treatment could indeed improve memory performance in APPswe/PS1dE9 mice, without affecting anxiety, depressive-like behavior or hypothalamus-pituitary-adrenal axis regulation. However, no treatment effects were observed on Aβ plaque load, pCREB or BDNF concentrations, or presynaptic density in the hippocampus, suggesting that other signaling pathways and/or effector molecules might be responsible for its cognition-enhancing effects. Presynaptic density in the stratum lucidum of the CA3 subregion was significantly higher in APPswe/PS1dE9 mice compared to WT controls, possibly reflecting a compensatory mechanism. In conclusion, PDEs in general, and PDE2 specifically, could be considered as promising therapeutic targets for cognition enhancement in AD, although the underlying mechanism of action remains to be elucidated. This article is part of a Special Issue entitled 'Cognitive Enhancers'.
Collapse
Affiliation(s)
- Annerieke S R Sierksma
- Department of Psychiatry and Neuropsychology, Faculty of Health, Medicine and Life Science, School for Mental Health and Neuroscience (MHeNS), Maastricht University, Maastricht, The Netherlands
| | | | | | | | | | | | | |
Collapse
|
29
|
Manaye KF, Allard JS, Kalifa S, Drew AC, Xu G, Ingram DK, de Cabo R, Mouton PR. 17α-estradiol attenuates neuron loss in ovariectomized Dtg AβPP/PS1 mice. J Alzheimers Dis 2012; 23:629-39. [PMID: 21157032 DOI: 10.3233/jad-2010-100993] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Quantitative microanalysis of brains from patients with Alzheimer's disease (AD) find neuronal loss and neuroinflammation in structures that control cognitive function. Though historically difficult to recapitulate in experimental models, several groups have recently reported that by middle-age, transgenic mice that co-express high levels of two AD-associated mutations, amyloid-β protein precursor (AβPP(swe)) and presenilin 1 (PS1(ΔE9)), undergo significant AD-type neuron loss in sub-cortical nuclei with heavy catecholaminergic projections to the hippocampal formation. Here we report that by 13 months of age these dtg AβPP(swe)/PS1(ΔE9) mice also show significant loss of pyramidal neuron in a critical region for learning and memory, the CA1 subregion of hippocampus, as a direct function of amyloid-β (Aβ) aggregation. We used these mice to test whether 17α-estradiol (17αE2), a less feminizing and non-carcinogenic enantiomer of 17β-estradiol, protects against this CA1 neuron loss. Female dtg AβPP(swe)/PS1(ΔE9) mice were ovariectomized at 8-9 months of age and treated for 60 days with either 17αE2 or placebo via subcutaneous pellets. Computerized stereology revealed that 17αE2 ameliorated the loss of neurons in CA1 and reduced microglial activation in the hippocampus. These findings support the view that 17αE2, which may act through non-genomic mechanisms independent of traditional estrogen receptors, could prevent or delay the progression of AD in older men and women.
Collapse
Affiliation(s)
- Kebreten F Manaye
- Department of Physiology & Biophysics, College of Medicine, Howard University, Washington, DC 20059, USA.
| | | | | | | | | | | | | | | |
Collapse
|
30
|
Armstrong BC, Le Boutillier JC, Petit TL. Ultrastructural synaptic changes associated with neurofibromatosis type 1: a quantitative analysis of hippocampal region CA1 in a Nf1(+/-) mouse model. Synapse 2011; 66:246-55. [PMID: 22121000 DOI: 10.1002/syn.21507] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2011] [Revised: 10/28/2011] [Accepted: 11/02/2011] [Indexed: 11/06/2022]
Abstract
Neurofibromatosis type 1 (NF1) is one of the most frequently diagnosed autosomal dominant inherited disorders resulting in neurological dysfunction, including an assortment of learning disabilities and cognitive deficits. To elucidate the neural mechanisms underlying the disorder, we employed a mouse model (Nf1(+/-) ) to conduct a quantitative analysis of ultrastructural changes associated with the NF1 disorder. Using both serial light and electron microscopy, we examined reconstructions of the CA1 region of the hippocampus, which is known to play a central role in many of the dysfunctions associated with NF1. In general, the morphology of synapses in both the Nf1(+/-) and wild-type groups of animals were similar. No differences were observed in synapse per neuron density, pre- and postsynaptic areas, or lengths. However, concave synapses were found to show a lower degree of curvature in the Nf1(+/-) mutant than in the wild type. These results indicate that the synaptic ultrastructure of Nf1(+/-) mice appears relatively normal with the exception of the degree of synaptic curvature in concave synapses, adding further support to the importance of synaptic curvature in synaptic plasticity, learning, and memory.
Collapse
Affiliation(s)
- Blair C Armstrong
- Department of Psychology and Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
| | | | | |
Collapse
|
31
|
Early onset amyloid lesions lead to severe neuritic abnormalities and local, but not global neuron loss in APPPS1 transgenic mice. Neurobiol Aging 2011; 32:2324.e1-6. [DOI: 10.1016/j.neurobiolaging.2010.08.014] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2010] [Revised: 08/17/2010] [Accepted: 08/27/2010] [Indexed: 12/25/2022]
|
32
|
Fortea J, Sala-Llonch R, Bartrés-Faz D, Lladó A, Solé-Padullés C, Bosch B, Antonell A, Olives J, Sanchez-Valle R, Molinuevo JL, Rami L. Cognitively preserved subjects with transitional cerebrospinal fluid ß-amyloid 1-42 values have thicker cortex in Alzheimer's disease vulnerable areas. Biol Psychiatry 2011; 70:183-90. [PMID: 21514924 DOI: 10.1016/j.biopsych.2011.02.017] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2010] [Revised: 02/15/2011] [Accepted: 02/15/2011] [Indexed: 01/20/2023]
Abstract
BACKGROUND Establishing the relationship between cerebrospinal fluid (CSF) ß-amyloid 1-42 (Aß) and cortical thickness (CTh) would represent a major step forward in the understanding of the Alzheimer's disease (AD) process. We studied this relationship in a group of healthy control subjects and subjects with subjective memory complaints with preserved cognitive function at neuropsychological testing. METHODS In this cross-sectional study, 33 individuals (17 healthy control subjects and 16 subjects with subjective memory complaints) underwent structural 3-Tesla magnetic resonance image scanning and a spinal tap. Cerebrospinal fluid Aß was measured by enzyme-linked immunosorbent assay. The relationship between CSF Aß values and CTh in several regions of interest, both susceptible and unrelated to AD pathology, was analyzed with a curve fit analysis and CTh difference maps were derived from group comparisons. RESULTS Dichotomizing the whole sample according to Aß values (cutoff 500 pg/mL), we found the expected cortical thinning in Aß positive subjects in temporoparietal areas (p < .05 corrected). When analyzing the relationship between CSF Aß and CTh in AD-susceptible regions, we found a significant inverted U-shaped relationship (quadratic). Therefore, the sample was further divided into tertiles (according to CSF Aß values) to perform subsequent subgroup comparisons. Increased CTh in temporoparietal areas and precuneus (p < .05 corrected) was found in the middle Aß tertile (CSF Aß between 416 and 597 pg/mL) when compared with the high Aß tertile (616-881 pg/mL). CONCLUSIONS The relationship between Aß and CTh in preclinical stages may not be linear. Cortical thickness in temporoparietal and precuneus regions is greater in subjects with transitional CSF Aß values.
Collapse
Affiliation(s)
- Juan Fortea
- Alzheimer's Disease and Other Cognitive Disorders Unit, Neurology Service, Hospital Clínic, Barcelona, Spain
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
33
|
Nikolajsen GN, Jensen MS, West MJ. Cholinergic axon length reduced by 300 meters in the brain of an Alzheimer mouse model. Neurobiol Aging 2011; 32:1927-31. [PMID: 21752495 DOI: 10.1016/j.neurobiolaging.2011.05.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2011] [Accepted: 05/10/2011] [Indexed: 11/17/2022]
Abstract
Modern stereological techniques have been used to show that the total length of the cholinergic fibers in the cerebral cortex of the APPswe/PS1deltaE9 mouse is reduced by almost 300 meters at 18 months of age and has a nonlinear relationship to the amount of transgenetically-induced amyloidosis. These data provide rigorous quantitative morphological evidence that Alzheimer's-like amyloidosis affects the axons of the cholinergic enervation of the cerebral cortex.
Collapse
|
34
|
Jiao X, Pang KCH, Beck KD, Minor TR, Servatius RJ. Avoidance perseveration during extinction training in Wistar-Kyoto rats: an interaction of innate vulnerability and stressor intensity. Behav Brain Res 2011; 221:98-107. [PMID: 21376086 DOI: 10.1016/j.bbr.2011.02.029] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2010] [Revised: 02/10/2011] [Accepted: 02/24/2011] [Indexed: 10/18/2022]
Abstract
Given that avoidance is a core feature of anxiety disorders, Wistar-Kyoto (WKY) rats may be a good model of anxiety vulnerability for their hypersensitivity to stress and trait behavioral inhibition. Here, we examined the influence of strain and shock intensity on avoidance acquisition and extinction. Accordingly, we trained WKY and Sprague-Dawley (SD) rats in lever-press avoidance using either 1.0-mA or 2.0-mA foot-shock. After extinction, neuronal activation was visualized by c-Fos for overall activity and parvalbumin immunoreactivity for gamma-aminobutyric acid (GABA) neuron in brain areas linked to anxiety (medial prefrontal cortex and amygdala). Consistent with earlier work, WKY rats acquired lever-press avoidance faster and to a greater extent than SD rats. However, the intensity of foot shock did not differentially affect acquisition. Although there were no differences during extinction in SD rats, avoidance responses of WKY rats trained with the higher foot shock perseverated during extinction compared to those WKY rats trained with lower foot shock intensity or SD rats. WKY rats trained with 2.0-mA shock exhibited less GABAergic activation in the basolateral amygdala after extinction. These findings suggest that inhibitory modulation in amygdala is important to ensure successful extinction learning. Deficits in avoidance extinction secondary to lower GABAergic activation in baslolateral amygdala may contribute to anxiety vulnerability in this animal model of inhibited temperament.
Collapse
Affiliation(s)
- Xilu Jiao
- Stress and Motivated Behavior Institute, NJMS-UMDNJ, Newark, NJ 07103, United States.
| | | | | | | | | |
Collapse
|
35
|
Activation of nicotinic α(7) acetylcholine receptor enhances long term potentation in wild type mice but not in APP(swe)/PS1ΔE9 mice. Neurosci Lett 2010; 487:325-9. [PMID: 20974225 DOI: 10.1016/j.neulet.2010.10.049] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2010] [Revised: 10/12/2010] [Accepted: 10/19/2010] [Indexed: 11/23/2022]
Abstract
Amyloid β (Aβ) plays a central role in Alzheimer's disease (AD) and binds to the nicotinic α(7) receptor (α(7) nAChR). Little is known about the degree to which the binding of Aβ to the α(7) nAChR influences the role of this receptor in long-term potentiation (LTP), however. We have studied the effect of the partial α(7) nAChR agonist SSR180711 on hippocampal slice preparations from normal wild type (Wt) and APP(swe)/PS1ΔE9 transgenic (Tg) mice. In the hippocampal slices from the 6 months old Wt mice, the application of both nicotine (5μM) and SSR180711 (300nM) resulted in a significant enhancement of LTP expressed in area CA1. However, in the Tg mice the application of SSR180711 did not result in an increase in LTP beyond control levels. The amount of binding of the α(7) nAChR ligand 125-I-α-bungarotoxin was not different between in Tg and Wt mice. These findings indicate that the α(7) nAChR is functionally blocked in the hippocampal neurons, downstream of the α(7) nAChR, and that this is likely due to an interaction between the receptor and Aβ, which leads to changes in LTP.
Collapse
|
36
|
Xu W, Zhan Y, Huang W, Wang X, Zhang S, Lei H. Reduction of hippocampal N-acetyl aspartate level in aged APPSwe/PS1dE9 transgenic mice is associated with degeneration of CA3 pyramidal neurons. J Neurosci Res 2010; 88:3155-60. [DOI: 10.1002/jnr.22479] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
37
|
Nielsen MS, Sørensen JC, Bjarkam CR. The substantia nigra pars compacta of the Göttingen minipig: an anatomical and stereological study. Brain Struct Funct 2009; 213:481-8. [DOI: 10.1007/s00429-009-0217-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2009] [Accepted: 08/07/2009] [Indexed: 12/19/2022]
|
38
|
Iacono D, Markesbery WR, Gross M, Pletnikova O, Rudow G, Zandi P, Troncoso JC. The Nun study: clinically silent AD, neuronal hypertrophy, and linguistic skills in early life. Neurology 2009; 73:665-73. [PMID: 19587326 DOI: 10.1212/wnl.0b013e3181b01077] [Citation(s) in RCA: 140] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND It is common to find substantial Alzheimer disease (AD) lesions, i.e., neuritic beta-amyloid plaques and neurofibrillary tangles, in the autopsied brains of elderly subjects with normal cognition assessed shortly before death. We have termed this status asymptomatic AD (ASYMAD). We assessed the morphologic substrate of ASYMAD compared to mild cognitive impairment (MCI) in subjects from the Nun Study. In addition, possible correlations between linguistic abilities in early life and the presence of AD pathology with and without clinical manifestations in late life were considered. METHODS Design-based stereology was used to measure the volumes of neuronal cell bodies, nuclei, and nucleoli in the CA1 region of hippocampus (CA1). Four groups of subjects were compared: ASYMAD (n = 10), MCI (n = 5), AD (n = 10), and age-matched controls (n = 13). Linguistic ability assessed in early life was compared among all groups. RESULTS A significant hypertrophy of the cell bodies (+44.9%), nuclei (+59.7%), and nucleoli (+80.2%) in the CA1 neurons was found in ASYMAD compared with MCI. Similar differences were observed with controls. Furthermore, significant higher idea density scores in early life were observed in controls and ASYMAD group compared to MCI and AD groups. CONCLUSIONS 1) Neuronal hypertrophy may constitute an early cellular response to Alzheimer disease (AD) pathology or reflect compensatory mechanisms that prevent cognitive impairment despite substantial AD lesions; 2) higher idea density scores in early life are associated with intact cognition in late life despite the presence of AD lesions.
Collapse
Affiliation(s)
- D Iacono
- Division of Neuropathology, Department of Pathology, Johns Hopkins University, School of Medicine, Ross Building 558, 720 Rutland Avenue, Baltimore, MD 21205, USA
| | | | | | | | | | | | | |
Collapse
|
39
|
Perez SE, Lumayag S, Kovacs B, Mufson EJ, Xu S. Beta-amyloid deposition and functional impairment in the retina of the APPswe/PS1DeltaE9 transgenic mouse model of Alzheimer's disease. Invest Ophthalmol Vis Sci 2008; 50:793-800. [PMID: 18791173 DOI: 10.1167/iovs.08-2384] [Citation(s) in RCA: 166] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
PURPOSE To determine whether beta-amyloid (Abeta) deposition affects the structure and function of the retina of the APPswe/PS1DeltaE9 transgenic (tg) mouse model of Alzheimer's disease. METHODS Retinas from 12- to 19-month old APPswe/PS1DeltaE9 tg and age-matched non-transgenic (ntg) littermates were single or double stained with thioflavine-S and antibodies against Abeta, glial fibrillar acidic protein (GFAP), microglial marker F4/80, choline acetyltransferase (ChAT), and syntaxin 1. Quantification of thioflavine-S positive plaques and retinal layer thickness was analyzed semi-quantitatively, whereas microglial cell size and levels of F4/80 immunoreactivity were evaluated using a densitometry program. Scotopic electroretinogram (ERG) recording was used to investigate retinal physiology in these mice. RESULTS Thioflavine-S positive plaques appeared at 12 months in the retinas of APPswe/PS1DeltaE9 tg mice with the majority of plaques in the outer and inner plexiform layers. Plaques were embedded in the inner plexiform layer strata displaying syntaxin 1 and ChAT. The number and size of the plaques in the retina increased with age. Plaques appeared earlier and in greater numbers in females than in male tg littermate mice. Microglial activity was significantly increased in the retinas of APPswe/PS1DeltaE9 tg mice. Although we did not detect neuronal degeneration in the retina, ERG recordings revealed a significant reduction in the amplitudes of a- and b-waves in aged APPswe/PS1DeltaE9 tg compared to ntg littermates. CONCLUSIONS The present findings suggest that Abeta deposition disrupts retinal structure and may contribute to the visual deficits seen in aged APPswe/PS1DeltaE9 tg mice. Whether Abeta is involved in other forms of age-related retinal dysfunction is unclear.
Collapse
Affiliation(s)
- Sylvia E Perez
- Department of Neurological Sciences, Rush University Medical Center, Chicago, Illinois, USA
| | | | | | | | | |
Collapse
|