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Trouche SG, Boutajangout A, Asuni A, Fontés P, Sigurdsson EM, Verdier JM, Mestre-Francés N. Amyloid-β targeting immunisation in aged non-human primate (Microcebus murinus). Brain Behav Immun 2023; 109:63-77. [PMID: 36592872 PMCID: PMC10023341 DOI: 10.1016/j.bbi.2022.12.021] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 12/06/2022] [Accepted: 12/29/2022] [Indexed: 12/31/2022] Open
Abstract
Non-human primates have an important translational value given their close phylogenetic relationship to humans. Studies in these animals remain essential for evaluating efficacy and safety of new therapeutic approaches, particularly in aging primates that display Alzheimer's disease (AD) -like pathology. With the objective to improve amyloid-β (Aβ) targeting immunotherapy, we investigated the safety and efficacy of an active immunisation with an Aβ derivative, K6Aβ1-30-NH2, in old non-human primates. Thirty-two aged (4-10 year-old) mouse lemurs were enrolled in the study, and received up to four subcutaneous injections of the vaccine in alum adjuvant or adjuvant alone. Even though antibody titres to Aβ were not high, pathological examination of the mouse lemur brains showed a significant reduction in intraneuronal Aβ that was associated with reduced microgliosis, and the vaccination did not lead to microhemorrhages. Moreover, a subtle cognitive improvement was observed in the vaccinated primates, which was probably linked to Aβ clearance. This Aβ derivative vaccine appeared to be safe as a prophylactic measure based on the brain analyses and because it did not appear to have detrimental effects on the general health of these old animals.
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Affiliation(s)
- Stéphanie G Trouche
- MMDN, Univ Montpellier, EPHE, INSERM, Montpellier, France; PSL Research University, Paris, France.
| | - Allal Boutajangout
- Departments of Neurology, and Neuroscience and Physiology, New York University Grossman School of Medicine, New York, United States.
| | - Ayodeji Asuni
- Department of Psychiatry, New York University Grossman School of Medicine, New York, United States.
| | | | - Einar M Sigurdsson
- Departments of Neuroscience and Physiology, and Psychiatry, Neuroscience Institute, New York University Grossman School of Medicine, New York, United States.
| | - Jean-Michel Verdier
- MMDN, Univ Montpellier, EPHE, INSERM, Montpellier, France; PSL Research University, Paris, France.
| | - Nadine Mestre-Francés
- MMDN, Univ Montpellier, EPHE, INSERM, Montpellier, France; PSL Research University, Paris, France.
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Mckean NE, Handley RR, Snell RG. A Review of the Current Mammalian Models of Alzheimer's Disease and Challenges That Need to Be Overcome. Int J Mol Sci 2021; 22:13168. [PMID: 34884970 PMCID: PMC8658123 DOI: 10.3390/ijms222313168] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 11/30/2021] [Accepted: 12/02/2021] [Indexed: 01/04/2023] Open
Abstract
Alzheimer's disease (AD) is one of the looming health crises of the near future. Increasing lifespans and better medical treatment for other conditions mean that the prevalence of this disease is expected to triple by 2050. The impact of AD includes both the large toll on individuals and their families as well as a large financial cost to society. So far, we have no way to prevent, slow, or cure the disease. Current medications can only alleviate some of the symptoms temporarily. Many animal models of AD have been created, with the first transgenic mouse model in 1995. Mouse models have been beset by challenges, and no mouse model fully captures the symptomatology of AD without multiple genetic mutations and/or transgenes, some of which have never been implicated in human AD. Over 25 years later, many mouse models have been given an AD-like disease and then 'cured' in the lab, only for the treatments to fail in clinical trials. This review argues that small animal models are insufficient for modelling complex disorders such as AD. In order to find effective treatments for AD, we need to create large animal models with brains and lifespan that are closer to humans, and underlying genetics that already predispose them to AD-like phenotypes.
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Affiliation(s)
- Natasha Elizabeth Mckean
- Applied Translational Genetics Group, School of Biological Sciences, University of Auckland, 3a Symonds Street, Auckland 1010, New Zealand; (N.E.M.); (R.R.H.)
- Centre for Brain Research, Faculty of Medical and Health Sciences, University of Auckland, Auckland 1010, New Zealand
| | - Renee Robyn Handley
- Applied Translational Genetics Group, School of Biological Sciences, University of Auckland, 3a Symonds Street, Auckland 1010, New Zealand; (N.E.M.); (R.R.H.)
- Centre for Brain Research, Faculty of Medical and Health Sciences, University of Auckland, Auckland 1010, New Zealand
| | - Russell Grant Snell
- Applied Translational Genetics Group, School of Biological Sciences, University of Auckland, 3a Symonds Street, Auckland 1010, New Zealand; (N.E.M.); (R.R.H.)
- Centre for Brain Research, Faculty of Medical and Health Sciences, University of Auckland, Auckland 1010, New Zealand
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3
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del Rio D, Beucher B, Lavigne M, Wehbi A, Gonzalez Dopeso-Reyes I, Saggio I, Kremer EJ. CAV-2 Vector Development and Gene Transfer in the Central and Peripheral Nervous Systems. Front Mol Neurosci 2019; 12:71. [PMID: 30983967 PMCID: PMC6449469 DOI: 10.3389/fnmol.2019.00071] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 03/07/2019] [Indexed: 12/11/2022] Open
Abstract
The options available for genetic modification of cells of the central nervous system (CNS) have greatly increased in the last decade. The current panoply of viral and nonviral vectors provides multifunctional platforms to deliver expression cassettes to many structures and nuclei. These cassettes can replace defective genes, modify a given pathway perturbed by diseases, or express proteins that can be selectively activated by drugs or light to extinguish or excite neurons. This review focuses on the use of canine adenovirus type 2 (CAV-2) vectors for gene transfer to neurons in the brain, spinal cord, and peripheral nervous system. We discuss (1) recent advances in vector production, (2) why CAV-2 vectors preferentially transduce neurons, (3) the mechanism underlying their widespread distribution via retrograde axonal transport, (4) how CAV-2 vectors have been used to address structure/function, and (5) their therapeutic applications.
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Affiliation(s)
- Danila del Rio
- Institut de Génétique Moléculaire de Montpellier, University of Montpellier, CNRS, Montpellier, France
| | - Bertrand Beucher
- PVM, BioCampus, CNRS, INSERM, University of Montpellier, Montpellier, France
| | - Marina Lavigne
- Institut de Génétique Moléculaire de Montpellier, University of Montpellier, CNRS, Montpellier, France
| | - Amani Wehbi
- Institut de Génétique Moléculaire de Montpellier, University of Montpellier, CNRS, Montpellier, France
| | | | - Isabella Saggio
- Department of Biology and Biotechnology “C. Darwin”, Sapienza University of Rome, Rome, Italy
- Institute of Structural Biology, School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Eric J. Kremer
- Institut de Génétique Moléculaire de Montpellier, University of Montpellier, CNRS, Montpellier, France
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4
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Mestre-Francés N, Serratrice N, Gennetier A, Devau G, Cobo S, Trouche SG, Fontès P, Zussy C, De Deurwaerdere P, Salinas S, Mennechet FJ, Dusonchet J, Schneider BL, Saggio I, Kalatzis V, Luquin-Piudo MR, Verdier JM, Kremer EJ. Exogenous LRRK2G2019S induces parkinsonian-like pathology in a nonhuman primate. JCI Insight 2018; 3:98202. [PMID: 30046008 DOI: 10.1172/jci.insight.98202] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Accepted: 06/19/2018] [Indexed: 12/22/2022] Open
Abstract
Parkinson's disease (PD) is the second most prevalent neurodegenerative disease among the elderly. To understand its pathogenesis and to test therapies, animal models that faithfully reproduce key pathological PD hallmarks are needed. As a prelude to developing a model of PD, we tested the tropism, efficacy, biodistribution, and transcriptional effect of canine adenovirus type 2 (CAV-2) vectors in the brain of Microcebus murinus, a nonhuman primate that naturally develops neurodegenerative lesions. We show that introducing helper-dependent (HD) CAV-2 vectors results in long-term, neuron-specific expression at the injection site and in afferent nuclei. Although HD CAV-2 vector injection induced a modest transcriptional response, no significant adaptive immune response was generated. We then generated and tested HD CAV-2 vectors expressing leucine-rich repeat kinase 2 (LRRK2) and LRRK2 carrying a G2019S mutation (LRRK2G2019S), which is linked to sporadic and familial autosomal dominant forms of PD. We show that HD-LRRK2G2019S expression induced parkinsonian-like motor symptoms and histological features in less than 4 months.
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Affiliation(s)
- Nadine Mestre-Francés
- MMDN, University of Montpellier, Ecole Pratique des Hautes Etudes, INSERM, PSL University, Montpellier, France
| | - Nicolas Serratrice
- Institut de Génétique Moléculaire de Montpellier, University of Montpellier, CNRS, Montpellier, France
| | - Aurélie Gennetier
- Institut de Génétique Moléculaire de Montpellier, University of Montpellier, CNRS, Montpellier, France
| | - Gina Devau
- MMDN, University of Montpellier, Ecole Pratique des Hautes Etudes, INSERM, PSL University, Montpellier, France
| | - Sandra Cobo
- MMDN, University of Montpellier, Ecole Pratique des Hautes Etudes, INSERM, PSL University, Montpellier, France
| | - Stéphanie G Trouche
- MMDN, University of Montpellier, Ecole Pratique des Hautes Etudes, INSERM, PSL University, Montpellier, France
| | - Pascaline Fontès
- MMDN, University of Montpellier, Ecole Pratique des Hautes Etudes, INSERM, PSL University, Montpellier, France
| | - Charleine Zussy
- Institut de Génétique Moléculaire de Montpellier, University of Montpellier, CNRS, Montpellier, France
| | | | - Sara Salinas
- Institut de Génétique Moléculaire de Montpellier, University of Montpellier, CNRS, Montpellier, France
| | - Franck Jd Mennechet
- Institut de Génétique Moléculaire de Montpellier, University of Montpellier, CNRS, Montpellier, France
| | - Julien Dusonchet
- Brain Mind Institute, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Bernard L Schneider
- Brain Mind Institute, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Isabella Saggio
- Department of Biology and Biotechnology "C. Darwin," Sapienza University of Rome, Rome, Italy.,Pasteur Institute, Cenci Bolognetti Foundation, Rome, Italy.,Institute of Molecular Biology and Pathology, CNR, Rome, Italy
| | - Vasiliki Kalatzis
- Institute of Neurosciences of Montpellier, INSERM, University of Montpellier, Montpellier, France
| | - M Rosario Luquin-Piudo
- Instituto de Investigación Sanitaria de Navarra, Pamplona, Spain.,Neurology Department, Clinica Universidad de Navarra, Pamplona, Spain.,Neuroscience Division, Center for Applied Medical Research, Universidad de Navarra, Pamplona, Spain
| | - Jean-Michel Verdier
- MMDN, University of Montpellier, Ecole Pratique des Hautes Etudes, INSERM, PSL University, Montpellier, France
| | - Eric J Kremer
- Institut de Génétique Moléculaire de Montpellier, University of Montpellier, CNRS, Montpellier, France
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5
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Drummond E, Wisniewski T. Alzheimer's disease: experimental models and reality. Acta Neuropathol 2017; 133:155-175. [PMID: 28025715 PMCID: PMC5253109 DOI: 10.1007/s00401-016-1662-x] [Citation(s) in RCA: 435] [Impact Index Per Article: 62.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Revised: 12/20/2016] [Accepted: 12/22/2016] [Indexed: 12/15/2022]
Abstract
Experimental models of Alzheimer's disease (AD) are critical to gaining a better understanding of pathogenesis and to assess the potential of novel therapeutic approaches. The most commonly used experimental animal models are transgenic mice that overexpress human genes associated with familial AD (FAD) that result in the formation of amyloid plaques. However, AD is defined by the presence and interplay of both amyloid plaques and neurofibrillary tangle pathology. The track record of success in AD clinical trials thus far has been very poor. In part, this high failure rate has been related to the premature translation of highly successful results in animal models that mirror only limited aspects of AD pathology to humans. A greater understanding of the strengths and weakness of each of the various models and the use of more than one model to evaluate potential therapies would help enhance the success of therapy translation from preclinical studies to patients. In this review, we summarize the pathological features and limitations of the major experimental models of AD, including transgenic mice, transgenic rats, various physiological models of sporadic AD and in vitro human cell culture models.
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Affiliation(s)
- Eleanor Drummond
- Center for Cognitive Neurology and Department of Neurology, NYU School of Medicine, Alexandria ERSP, 450 East 29th Street, New York, NY, 10016, USA
| | - Thomas Wisniewski
- Center for Cognitive Neurology and Departments of Neurology, Pathology and Psychiatry, NYU School of Medicine, Alexandria ERSP, 450 East 29th Street, New York, NY, 10016, USA.
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6
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Hara H, Ono F, Nakamura S, Matsumoto SE, Jin H, Hattori N, Tabira T. An Oral Aβ Vaccine Using a Recombinant Adeno-Associated Virus Vector in Aged Monkeys: Reduction in Plaque Amyloid and Increase in Aβ Oligomers. J Alzheimers Dis 2016; 54:1047-1059. [DOI: 10.3233/jad-160514] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Hideo Hara
- National Institute for Longevity Sciences, National Center for Geriatrics and Gerontology, Morioka, Obu, Aichi, Japan
- Division of Neurology, Department of Internal Medicine, Faculty of Medicine, Saga University, Saga, Japan
| | - Fumiko Ono
- The Corporation for Production and Research of Laboratory Primates, Tsukuba, Ibaraki, Japan
- Faculty of Risk and Crisis Management, Chiba Institute of Science, Shiomi, Choshi, Chiba, Japan
| | - Shinichiro Nakamura
- The Corporation for Production and Research of Laboratory Primates, Tsukuba, Ibaraki, Japan
- Shiga University of Medical Science, Research Center for Animal Life Science, Seta-Tsukinowa, Otsu, Shiga, Japan
| | - Shin-ei Matsumoto
- National Institute for Longevity Sciences, National Center for Geriatrics and Gerontology, Morioka, Obu, Aichi, Japan
- Department of Diagnosis, Prevention and Treatment of Dementia, Graduate School of Medicine, Juntendo University, Bunkyo-ku, Tokyo, Japan
| | - Haifeng Jin
- Department of Diagnosis, Prevention and Treatment of Dementia, Graduate School of Medicine, Juntendo University, Bunkyo-ku, Tokyo, Japan
| | - Nobutaka Hattori
- Department of Diagnosis, Prevention and Treatment of Dementia, Graduate School of Medicine, Juntendo University, Bunkyo-ku, Tokyo, Japan
| | - Takeshi Tabira
- National Institute for Longevity Sciences, National Center for Geriatrics and Gerontology, Morioka, Obu, Aichi, Japan
- Department of Diagnosis, Prevention and Treatment of Dementia, Graduate School of Medicine, Juntendo University, Bunkyo-ku, Tokyo, Japan
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7
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Verdier JM, Acquatella I, Lautier C, Devau G, Trouche S, Lasbleiz C, Mestre-Francés N. Lessons from the analysis of nonhuman primates for understanding human aging and neurodegenerative diseases. Front Neurosci 2015; 9:64. [PMID: 25788873 PMCID: PMC4349082 DOI: 10.3389/fnins.2015.00064] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Accepted: 02/13/2015] [Indexed: 12/13/2022] Open
Abstract
Animal models are necessary tools for solving the most serious challenges facing medical research. In aging and neurodegenerative disease studies, rodents occupy a place of choice. However, the most challenging questions about longevity, the complexity and functioning of brain networks or social intelligence can almost only be investigated in nonhuman primates. Beside the fact that their brain structure is much closer to that of humans, they develop highly complex cognitive strategies and they are visually-oriented like humans. For these reasons, they deserve consideration, although their management and care are more complicated and the related costs much higher. Despite these caveats, considerable scientific advances have been possible using nonhuman primates. This review concisely summarizes their role in the study of aging and of the mechanisms involved in neurodegenerative disorders associated mainly with cognitive dysfunctions (Alzheimer's and prion diseases) or motor deficits (Parkinson's and related diseases).
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Affiliation(s)
- Jean-Michel Verdier
- Université de Montpellier Montpellier, France ; Institut National de la Santé et de la Recherche Médicale, U1198 Montpellier, France ; Ecole Pratique des Hautes Etudes Paris, France
| | - Isabelle Acquatella
- Université de Montpellier Montpellier, France ; Institut National de la Santé et de la Recherche Médicale, U1198 Montpellier, France ; Ecole Pratique des Hautes Etudes Paris, France
| | - Corinne Lautier
- Université de Montpellier Montpellier, France ; Institut National de la Santé et de la Recherche Médicale, U1198 Montpellier, France ; Ecole Pratique des Hautes Etudes Paris, France
| | - Gina Devau
- Université de Montpellier Montpellier, France ; Institut National de la Santé et de la Recherche Médicale, U1198 Montpellier, France ; Ecole Pratique des Hautes Etudes Paris, France
| | - Stéphanie Trouche
- Université de Montpellier Montpellier, France ; Institut National de la Santé et de la Recherche Médicale, U1198 Montpellier, France ; Ecole Pratique des Hautes Etudes Paris, France
| | - Christelle Lasbleiz
- Université de Montpellier Montpellier, France ; Institut National de la Santé et de la Recherche Médicale, U1198 Montpellier, France ; Ecole Pratique des Hautes Etudes Paris, France
| | - Nadine Mestre-Francés
- Université de Montpellier Montpellier, France ; Institut National de la Santé et de la Recherche Médicale, U1198 Montpellier, France ; Ecole Pratique des Hautes Etudes Paris, France
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8
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Roy M, Cardoso C, Dorieux O, Malgorn C, Epelbaum S, Petit F, Kraska A, Brouillet E, Delatour B, Perret M, Aujard F, Dhenain M. Age-associated evolution of plasmatic amyloid in mouse lemur primates: relationship with intracellular amyloid deposition. Neurobiol Aging 2014; 36:149-56. [PMID: 25131002 DOI: 10.1016/j.neurobiolaging.2014.07.017] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Revised: 07/02/2014] [Accepted: 07/12/2014] [Indexed: 01/08/2023]
Abstract
Alzheimer's disease (AD) is the most common age-related neurodegenerative disorder. Amyloid-β peptide (Aβ) deposition in the brain is one of its hallmarks, and the measure of plasma Aβ is considered to be a biomarker for anti-amyloid drug efficacy in animal models of AD. However, age-associated plasmatic Aβ modulation in animal models is practically never addressed in the literature. Mouse lemur primates are used as a model of normal and AD-like cerebral aging. Here, we studied the effect of age on plasmatic Aβ in 58 mouse lemurs aged from 1 to 10 years. A subset of animals presented high plasmatic Aβ, and the proportion of animals with high plasmatic Aβ was higher in aged animals as compared with young ones. Histologic evaluation of the brain of some of these animals was carried out to assess extracellular and intracellular amyloid load. In aged lemurs, plasmatic Aβ was negatively correlated with the density of neurons accumulating deposits of Aβ.
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Affiliation(s)
- Maggie Roy
- CEA, DSV, I2BM, MIRCen, URA CEA CNRS 2210, Fontenay aux Roses, France; CNRS, URA 2210, Fontenay aux Roses, France; Research Center on Aging, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Cécile Cardoso
- CEA, DSV, I2BM, MIRCen, URA CEA CNRS 2210, Fontenay aux Roses, France; CNRS, URA 2210, Fontenay aux Roses, France
| | - Olène Dorieux
- CEA, DSV, I2BM, MIRCen, URA CEA CNRS 2210, Fontenay aux Roses, France; CNRS, URA 2210, Fontenay aux Roses, France; CNRS UMR 7179, MNHN, Brunoy, France
| | - Carole Malgorn
- CEA, DSV, I2BM, MIRCen, URA CEA CNRS 2210, Fontenay aux Roses, France; CNRS, URA 2210, Fontenay aux Roses, France
| | - Stéphane Epelbaum
- Sorbonne Universités, Paris, France; UPMC Univ Paris 06 UMR S 1127, Paris, France; Inserm, U 1127, Paris, France; CNRS UMR 7225, Paris, France; ICM, Paris, France
| | - Fanny Petit
- CEA, DSV, I2BM, MIRCen, URA CEA CNRS 2210, Fontenay aux Roses, France; CNRS, URA 2210, Fontenay aux Roses, France
| | - Audrey Kraska
- CEA, DSV, I2BM, MIRCen, URA CEA CNRS 2210, Fontenay aux Roses, France; CNRS, URA 2210, Fontenay aux Roses, France
| | - Emmanuel Brouillet
- CEA, DSV, I2BM, MIRCen, URA CEA CNRS 2210, Fontenay aux Roses, France; CNRS, URA 2210, Fontenay aux Roses, France
| | - Benoît Delatour
- Sorbonne Universités, Paris, France; UPMC Univ Paris 06 UMR S 1127, Paris, France; Inserm, U 1127, Paris, France; CNRS UMR 7225, Paris, France; ICM, Paris, France
| | | | | | - Marc Dhenain
- CEA, DSV, I2BM, MIRCen, URA CEA CNRS 2210, Fontenay aux Roses, France; CNRS, URA 2210, Fontenay aux Roses, France.
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9
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Toledano A, Álvarez M, López-Rodríguez A, Toledano-Díaz A, Fernández-Verdecia C. Does Alzheimer disease exist in all primates? Alzheimer pathology in non-human primates and its pathophysiological implications (II). NEUROLOGÍA (ENGLISH EDITION) 2014. [DOI: 10.1016/j.nrleng.2011.05.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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10
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Joseph-Mathurin N, Dorieux O, Trouche SG, Boutajangout A, Kraska A, Fontès P, Verdier JM, Sigurdsson EM, Mestre-Francés N, Dhenain M. Amyloid beta immunization worsens iron deposits in the choroid plexus and cerebral microbleeds. Neurobiol Aging 2013; 34:2613-22. [PMID: 23796662 DOI: 10.1016/j.neurobiolaging.2013.05.013] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2012] [Revised: 04/20/2013] [Accepted: 05/16/2013] [Indexed: 11/15/2022]
Abstract
Anti-amyloid beta (Aβ) immunotherapy provides potential benefits in Alzheimer's disease patients. Nevertheless, strategies based on Aβ1-42 peptide induced encephalomyelitis and possible microhemorrhages. These outcomes were not expected from studies performed in rodents. It is critical to determine if other animal models better predict side effects of immunotherapies. Mouse lemur primates can develop amyloidosis with aging. Here we used old lemurs to study immunotherapy based on Aβ1-42 or Aβ-derivative (K6Aβ1-30). We followed anti-Aβ40 immunoglobulin G and M responses and Aβ levels in plasma. In vivo magnetic resonance imaging and histology were used to evaluate amyloidosis, neuroinflammation, vasogenic edema, microhemorrhages, and brain iron deposits. The animals responded mainly to the Aβ1-42 immunogen. This treatment induced immune response and increased Aβ levels in plasma and also microhemorrhages and iron deposits in the choroid plexus. A complementary study of untreated lemurs showed iron accumulation in the choroid plexus with normal aging. Worsening of iron accumulation is thus a potential side effect of Aβ-immunization at prodromal stages of Alzheimer's disease, and should be monitored in clinical trials.
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Affiliation(s)
- Nelly Joseph-Mathurin
- CEA, DSV, I2BM, MIRCen, 18 route du panorama, 92265 Fontenay-aux-Roses cedex, France
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11
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Bertrand A, Pasquier A, Petiet A, Wiggins C, Kraska A, Joseph-Mathurin N, Aujard F, Mestre-Francés N, Dhenain M. Micro-MRI study of cerebral aging: ex vivo detection of hippocampal subfield reorganization, microhemorrhages and amyloid plaques in mouse lemur primates. PLoS One 2013; 8:e56593. [PMID: 23460806 PMCID: PMC3584101 DOI: 10.1371/journal.pone.0056593] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2012] [Accepted: 01/11/2013] [Indexed: 12/04/2022] Open
Abstract
Mouse lemurs are non-human primate models of cerebral aging and neurodegeneration. Much smaller than other primates, they recapitulate numerous features of human brain aging, including progressive cerebral atrophy and correlation between regional atrophy and cognitive impairments. Characterization of brain atrophy in mouse lemurs has been done by MRI measures of regional CSF volume and by MRI measures of regional atrophy. Here, we further characterize mouse lemur brain aging using ex vivo MR microscopy (31 µm in-plane resolution). First, we performed a non-biased, direct volumetric quantification of dentate gyrus and extended Ammon's horn. We show that both dentate gyrus and Ammon's horn undergo an age-related reorganization leading to a growth of the dentate gyrus and an atrophy of the Ammon's horn, even in the absence of global hippocampal atrophy. Second, on these first MR microscopic images of the mouse lemur brain, we depicted cortical and hippocampal hypointense spots. We demonstrated that their incidence increases with aging and that they correspond either to amyloid deposits or to cerebral microhemorrhages.
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Affiliation(s)
- Anne Bertrand
- CNRS (Centre National de la Recherche Scientifique), URA2210 (Unité de Recherche Autonome 2210), Fontenay-aux-Roses, France
- CEA (Commissariat à l'Energie Atomique et aux Energies Alternatives), DSV (Direction des Sciences du Vivant), I2BM (Institut d'Imagerie BioMédicale), MIRCen (Molecular Imaging Reseach CENter), Fontenay-aux-Roses, France
- CEA (Commissariat à l'Energie Atomique et aux Energies Alternatives), I2BM (Institut d'Imagerie BioMédicale), Neurospin, Gif-sur-Yvette, France
| | - Adrien Pasquier
- CNRS (Centre National de la Recherche Scientifique), URA2210 (Unité de Recherche Autonome 2210), Fontenay-aux-Roses, France
- CEA (Commissariat à l'Energie Atomique et aux Energies Alternatives), DSV (Direction des Sciences du Vivant), I2BM (Institut d'Imagerie BioMédicale), MIRCen (Molecular Imaging Reseach CENter), Fontenay-aux-Roses, France
| | - Alexandra Petiet
- CNRS (Centre National de la Recherche Scientifique), URA2210 (Unité de Recherche Autonome 2210), Fontenay-aux-Roses, France
- CEA (Commissariat à l'Energie Atomique et aux Energies Alternatives), DSV (Direction des Sciences du Vivant), I2BM (Institut d'Imagerie BioMédicale), MIRCen (Molecular Imaging Reseach CENter), Fontenay-aux-Roses, France
- CEA (Commissariat à l'Energie Atomique et aux Energies Alternatives), I2BM (Institut d'Imagerie BioMédicale), Neurospin, Gif-sur-Yvette, France
| | - Christopher Wiggins
- CEA (Commissariat à l'Energie Atomique et aux Energies Alternatives), I2BM (Institut d'Imagerie BioMédicale), Neurospin, Gif-sur-Yvette, France
| | - Audrey Kraska
- CNRS (Centre National de la Recherche Scientifique), URA2210 (Unité de Recherche Autonome 2210), Fontenay-aux-Roses, France
- CEA (Commissariat à l'Energie Atomique et aux Energies Alternatives), DSV (Direction des Sciences du Vivant), I2BM (Institut d'Imagerie BioMédicale), MIRCen (Molecular Imaging Reseach CENter), Fontenay-aux-Roses, France
| | - Nelly Joseph-Mathurin
- CNRS (Centre National de la Recherche Scientifique), URA2210 (Unité de Recherche Autonome 2210), Fontenay-aux-Roses, France
- CEA (Commissariat à l'Energie Atomique et aux Energies Alternatives), DSV (Direction des Sciences du Vivant), I2BM (Institut d'Imagerie BioMédicale), MIRCen (Molecular Imaging Reseach CENter), Fontenay-aux-Roses, France
| | - Fabienne Aujard
- UMR CNRS/MNHN 7179 (Unité Mixte de Recherche, Centre National de la Recherche Scientifique/Muséum National d'Histoire Naturelle), Mecadev (MECanismes ADaptatifs et EVolution), Brunoy, France
| | - Nadine Mestre-Francés
- INSERM U710- EPHE-UM2 (Institut National de la Santé et de la Recherche Médicale, Ecole Pratique des Hautes Etudes, Université Montpellier 2), Montpellier, France
| | - Marc Dhenain
- CNRS (Centre National de la Recherche Scientifique), URA2210 (Unité de Recherche Autonome 2210), Fontenay-aux-Roses, France
- CEA (Commissariat à l'Energie Atomique et aux Energies Alternatives), DSV (Direction des Sciences du Vivant), I2BM (Institut d'Imagerie BioMédicale), MIRCen (Molecular Imaging Reseach CENter), Fontenay-aux-Roses, France
- CEA (Commissariat à l'Energie Atomique et aux Energies Alternatives), I2BM (Institut d'Imagerie BioMédicale), Neurospin, Gif-sur-Yvette, France
- * E-mail:
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Toledano A, Álvarez MI, López-Rodríguez AB, Toledano-Díaz A, Fernández-Verdecia CI. [Does Alzheimer's disease exist in all primates? Alzheimer pathology in non-human primates and its pathophysiological implications (II)]. Neurologia 2011; 29:42-55. [PMID: 21871692 DOI: 10.1016/j.nrl.2011.05.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2011] [Accepted: 05/29/2011] [Indexed: 11/19/2022] Open
Abstract
INTRODUCTION In the ageing process there are some species of non-human primates which can show some of the defining characteristics of the Alzheimer's disease (AD) of man, both in neuropathological changes and cognitive-behavioural symptoms. The study of these species is of prime importance to understand AD and develop therapies to combat this neurodegenerative disease. DEVELOPMENT In this second part of the study, these AD features are discussed in the most important non-experimental AD models (Mouse Lemur -Microcebus murinus, Caribbean vervet -Chlorocebus aethiops, and the Rhesus and stump-tailed macaque -Macaca mulatta and M. arctoides) and experimental models (lesional, neurotoxic, pharmacological, immunological, etc.) non-human primates. In all these models cerebral amyloid neuropathology can occur in senility, although with different levels of incidence (100% in vervets;<30% in macaques). The differences between normal and pathological (Alzheimer's) senility in these species are difficult to establish due to the lack of cognitive-behavioural studies in the many groups analysed, as well as the controversy in the results of these studies when they were carried out. However, in some macaques, a correlation between a high degree of functional brain impairment and a large number of neuropathological changes ("possible AD") has been found. CONCLUSIONS In some non-human primates, such as the macaque, the existence of a possible continuum between "normal" ageing process, "normal" ageing with no deep neuropathological and cognitive-behavioural changes, and "pathological ageing" (or "Alzheimer type ageing"), may be considered. In other cases, such as the Caribbean vervet, neuropathological changes are constant and quite marked, but its impact on cognition and behaviour does not seem to be very important. This does assume the possible existence in the human senile physiological regression of a stable phase without dementia even if neuropathological changes appeared.
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Abdel Rassoul R, Alves S, Pantesco V, De Vos J, Michel B, Perret M, Mestre-Francés N, Verdier JM, Devau G. Distinct transcriptome expression of the temporal cortex of the primate Microcebus murinus during brain aging versus Alzheimer's disease-like pathology. PLoS One 2010; 5. [PMID: 20862281 PMCID: PMC2940844 DOI: 10.1371/journal.pone.0012770] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2010] [Accepted: 08/01/2010] [Indexed: 11/24/2022] Open
Abstract
Aging is the primary risk factor of neurodegenerative disorders such as Alzheimer's disease (AD). However, the molecular events occurring during brain aging are extremely complex and still largely unknown. For a better understanding of these age-associated modifications, animal models as close as possible to humans are needed. We thus analyzed the transcriptome of the temporal cortex of the primate Microcebus murinus using human oligonucleotide microarrays (Affymetrix). Gene expression profiles were assessed in the temporal cortex of 6 young adults, 10 healthy old animals and 2 old, “AD-like” animals that presented ß-amyloid plaques and cortical atrophy, which are pathognomonic signs of AD in humans. Gene expression data of the 14,911 genes that were detected in at least 3 samples were analyzed. By SAM (significance analysis of microarrays), we identified 47 genes that discriminated young from healthy old and “AD-like” animals. These findings were confirmed by principal component analysis (PCA). ANOVA of the expression data from the three groups identified 695 genes (including the 47 genes previously identified by SAM and PCA) with significant changes of expression in old and “AD-like” in comparison to young animals. About one third of these genes showed similar changes of expression in healthy aging and in “AD-like” animals, whereas more than two thirds showed opposite changes in these two groups in comparison to young animals. Hierarchical clustering analysis of the 695 markers indicated that each group had distinct expression profiles which characterized each group, especially the “AD-like” group. Functional categorization showed that most of the genes that were up-regulated in healthy old animals and down-regulated in “AD-like” animals belonged to metabolic pathways, particularly protein synthesis. These data suggest the existence of compensatory mechanisms during physiological brain aging that disappear in “AD-like” animals. These results open the way to new exploration of physiological and “AD-like” aging in primates.
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Affiliation(s)
- Ronza Abdel Rassoul
- Université Montpellier 2, Montpellier, France; Inserm U710, Montpellier, France; EPHE, Paris, France
| | - Sabine Alves
- Université Montpellier 2, Montpellier, France; Inserm U710, Montpellier, France; EPHE, Paris, France
| | - Véronique Pantesco
- CHU Montpellier, Institute for Research in Biotherapy, Hôpital Saint-Eloi, Montpellier, France
| | - John De Vos
- CHU Montpellier, Institute for Research in Biotherapy, Hôpital Saint-Eloi, Montpellier, France
| | - Bernard Michel
- Université Montpellier 2, Montpellier, France; Inserm U710, Montpellier, France; EPHE, Paris, France
- Service de Neurologie, Hôpital Ste Marguerite, Marseille, France
| | | | - Nadine Mestre-Francés
- Université Montpellier 2, Montpellier, France; Inserm U710, Montpellier, France; EPHE, Paris, France
| | - Jean-Michel Verdier
- Université Montpellier 2, Montpellier, France; Inserm U710, Montpellier, France; EPHE, Paris, France
| | - Gina Devau
- Université Montpellier 2, Montpellier, France; Inserm U710, Montpellier, France; EPHE, Paris, France
- * E-mail:
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14
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Boutajangout A, Goni F, Knudsen E, Schreiber F, Asuni A, Quartermain D, Frangione B, Chabalgoity A, Wisniewski T, Sigurdsson EM. Diminished amyloid-beta burden in Tg2576 mice following a prophylactic oral immunization with a salmonella-based amyloid-beta derivative vaccine. J Alzheimers Dis 2010; 18:961-72. [PMID: 19749432 DOI: 10.3233/jad-2009-1204] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Immunotherapy holds great promise for Alzheimer's disease (AD) and other conformational disorders but certain adverse reactions need to be overcome. Prior to the side effects in the first Elan/Wyeth AD vaccine trial, we proposed using amyloid-beta (Abeta) derivatives as a safer approach. The route of administration may also affect vaccine safety. To assess the feasibility of oral immunization that promotes mucosal immunity, Tg2576 AD model mice were treated prophylactically three times over 6 weeks starting at 3-5 months of age with a Salmonella vaccine expressing K6Abeta(1-30). At 22-24 months of age, cortical Abeta plaque burden and total Abeta(40/42) levels were reduced by 48-75% in the immunized mice compared to controls, which received unmodified Salmonella. Plaque clearance was not associated with increased microglial activation, which may be explained by the long treatment period. Furthermore, cerebral microhemorrhages were not increased in the treated mice in contrast to several passive Abeta antibody studies. These results further support our findings with this immunogen delivered subcutaneously and demonstrate its efficacy when given orally, which may provide added benefits for human use.
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Affiliation(s)
- Allal Boutajangout
- Department of Physiology and Neuroscience, New York University School of Medicine, New York, NY 10016, USA
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15
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Fu HJ, Liu B, Frost JL, Lemere CA. Amyloid-beta immunotherapy for Alzheimer's disease. CNS & NEUROLOGICAL DISORDERS-DRUG TARGETS 2010; 9:197-206. [PMID: 20205640 DOI: 10.2174/187152710791012017] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2009] [Accepted: 12/12/2009] [Indexed: 12/23/2022]
Abstract
Alzheimer's disease (AD) is a progressive, degenerative disorder of the brain and the most common form of dementia among the elderly. As the population grows and lifespan is extended, the number of AD patients will continue to rise. Current clinical therapies for AD provide partial symptomatic benefits for some patients; however, none of them modify disease progression. Amyloid-beta (Abeta) peptide, the major component of senile plaques in AD patients, is considered to play a crucial role in the pathogenesis of AD thereby leading to Abeta as a target for treatment. Abeta immunotherapy has been shown to induce a marked reduction in amyloid burden and an improvement in cognitive function in animal models. Although preclinical studies were successful, the initial human clinical trial of an active Abeta vaccine was halted due to the development of meningoencephalitis in approximately 6% of the vaccinated AD patients. Some encouraging outcomes, including signs of cognitive stabilization and apparent plaque clearance, were obtained in subset of patients who generated antibody titers. These promising preliminary data support further efforts to refine Abeta immunotherapy to produce highly effective and safer active and passive vaccines for AD. Furthermore, some new human clinical trials for both active and passive Abeta immunotherapy are underway. In this review, we will provide an update of Abeta immunotherapy in animal models and in human beings, as well as discuss the possible mechanisms underlying Abeta immunotherapy for AD.
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Affiliation(s)
- H J Fu
- Center for Neurologic Diseases, Department of Neurology, Brigham & Women's Hospital and Harvard Medical School, Boston, MA, 02115, USA
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Wisniewski T, Boutajangout A. Vaccination as a therapeutic approach to Alzheimer's disease. ACTA ACUST UNITED AC 2010; 77:17-31. [PMID: 20101719 DOI: 10.1002/msj.20156] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Alzheimer's disease is the most common cause of dementia worldwide. Alzheimer's disease is a member of a broad range of neurodegenerative diseases characterized pathologically by the conformational change of a normal protein into a pathological conformer with a high beta-sheet content that renders it neurotoxic. In the case of Alzheimer's disease, the normal soluble amyloid beta peptide is converted into oligomeric/fibrillar amyloid beta. The oligomeric forms of amyloid beta have been hypothesized to be the most toxic, whereas fibrillar amyloid beta becomes deposited as amyloid plaques and congophilic angiopathy, which both serve as neuropathological markers of the disease. In addition, the accumulation of abnormally phosphorylated tau as soluble toxic oligomers and as neurofibrillary tangles is a critical part of the pathology. Numerous therapeutic interventions are under investigation to prevent and treat Alzheimer's disease. Among the most exciting and advanced of these approaches is vaccination. Immunomodulation is being tried for a range of neurodegenerative disorders, with great success being reported in most model animal trials; however, the much more limited human data have shown more modest clinical success so far, with encephalitis occurring in a minority of patients treated with active immunization. The immunomodulatory approaches for neurodegenerative diseases involve targeting a self-protein, albeit in an abnormal conformation; hence, effective enhanced clearance of the disease-associated conformer has to be balanced with the potential risk of stimulating excessive toxic inflammation within the central nervous system. The design of future immunomodulatory approaches that are more focused is dependent on addressing a number of questions, including when is the best time to start immunization, what are the most appropriate targets for vaccination, and is amyloid central to the pathogenesis of Alzheimer's disease or is it critical to target tau-related pathology also. In this review, we discuss the past experience with vaccination for Alzheimer's disease and the development of possible future strategies that target both amyloid beta-related and tau-related pathologies.
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Affiliation(s)
- Thomas Wisniewski
- Department of Neurology, New York University School of Medicine, New York, NY, USA
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Zotova E, Nicoll JAR, Kalaria R, Holmes C, Boche D. Inflammation in Alzheimer's disease: relevance to pathogenesis and therapy. Alzheimers Res Ther 2010; 2:1. [PMID: 20122289 PMCID: PMC2874260 DOI: 10.1186/alzrt24] [Citation(s) in RCA: 147] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Evidence for the involvement of inflammatory processes in the pathogenesis of Alzheimer's disease (AD) has been documented for a long time. However, the inflammation hypothesis in relation to AD pathology has emerged relatively recently. Even in this hypothesis, the inflammatory reaction is still considered to be a downstream effect of the accumulated proteins (amyloid beta (Abeta) and tau). This review aims to highlight the importance of the immune processes involved in AD pathogenesis based on the outcomes of the two major inflammation-relevant treatment strategies against AD developed and tested to date in animal studies and human clinical trials - the use of anti-inflammatory drugs and immunisation against Abeta.
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Affiliation(s)
- Elina Zotova
- Division of Clinical Neurosciences, School of Medicine, University of Southampton, Mailpoint 806, Level D, South Pathology Block, Southampton General Hospital, Southampton, SO16 6YD, UK
| | - James AR Nicoll
- Division of Clinical Neurosciences, School of Medicine, University of Southampton, Mailpoint 806, Level D, South Pathology Block, Southampton General Hospital, Southampton, SO16 6YD, UK
- Neuropathology, Department of Cellular Pathology, Southampton University Hospitals NHS Trust, Southampton, SO16 6YD, UK
| | - Raj Kalaria
- Institute for Ageing and Health, Campus for Ageing and Vitality, Newcastle University, Newcastle upon Tyne NE4 5PL, UK
| | - Clive Holmes
- Division of Clinical Neurosciences, School of Medicine, University of Southampton, Mailpoint 806, Level D, South Pathology Block, Southampton General Hospital, Southampton, SO16 6YD, UK
- Memory Assessment Centre, Moorgreen Hospital, Hampshire Partnership Trust, Southampton, SO30 3JB, UK
| | - Delphine Boche
- Division of Clinical Neurosciences, School of Medicine, University of Southampton, Mailpoint 806, Level D, South Pathology Block, Southampton General Hospital, Southampton, SO16 6YD, UK
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Wisniewski T. AD vaccines: conclusions and future directions. CNS & NEUROLOGICAL DISORDERS-DRUG TARGETS 2009; 8:160-6. [PMID: 19355935 DOI: 10.2174/187152709787847289] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Thomas Wisniewski
- New York University School of Medicine, Millhauser Laboratory, New York, NY 10016, USA.
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Age-associated cerebral atrophy in mouse lemur primates. Neurobiol Aging 2009; 32:894-906. [PMID: 19564059 DOI: 10.1016/j.neurobiolaging.2009.05.018] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2008] [Revised: 04/03/2009] [Accepted: 05/27/2009] [Indexed: 01/22/2023]
Abstract
We assessed the regional brain atrophy in mouse lemur primates from 4.7T T2-weighted magnetic resonance images. Thirty animals aged from 1.9 to 11.3 years were imaged. Sixty-one percent of the 23 animals older than 3 years involved in the study displayed an atrophy process. Cross-sectional analysis suggests that the atrophy follows a gradual pathway, starting in the frontal region then involving the temporal and/or the parietal part of the brain and finally the occipital region. Histological evaluation of five animals selected according to various stages of atrophy suggested that extracellular amyloid deposits and tau pathology cannot explain by themselves this atrophy and that intracellular amyloid deposition is more closely linked to this pathology. This study suggests that most of the age-related atrophy occurring in mouse lemurs is caused by one clinical, evolving, pathological process. The ability to follow this pathology non-invasively by MRI will allow to further characterize it and evaluate its relationship with neuropathological lesions that are involved in human diseases such as Alzheimer.
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Deane R, Bell RD, Sagare A, Zlokovic BV. Clearance of amyloid-beta peptide across the blood-brain barrier: implication for therapies in Alzheimer's disease. CNS & NEUROLOGICAL DISORDERS DRUG TARGETS 2009; 8:16-30. [PMID: 19275634 PMCID: PMC2872930 DOI: 10.2174/187152709787601867] [Citation(s) in RCA: 404] [Impact Index Per Article: 26.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The main receptors for amyloid-beta peptide (Abeta) transport across the blood-brain barrier (BBB) from brain to blood and blood to brain are low-density lipoprotein receptor related protein-1 (LRP1) and receptor for advanced glycation end products (RAGE), respectively. In normal human plasma a soluble form of LRP1 (sLRP1) is a major endogenous brain Abeta 'sinker' that sequesters some 70 to 90 % of plasma Abeta peptides. In Alzheimer's disease (AD), the levels of sLRP1 and its capacity to bind Abeta are reduced which increases free Abeta fraction in plasma. This in turn may increase brain Abeta burden through decreased Abeta efflux and/or increased Abeta influx across the BBB. In Abeta immunotherapy, anti-Abeta antibody sequestration of plasma Abeta enhances the peripheral Abeta 'sink action'. However, in contrast to endogenous sLRP1 which does not penetrate the BBB, some anti-Abeta antibodies may slowly enter the brain which reduces the effectiveness of their sink action and may contribute to neuroinflammation and intracerebral hemorrhage. Anti-Abeta antibody/Abeta immune complexes are rapidly cleared from brain to blood via FcRn (neonatal Fc receptor) across the BBB. In a mouse model of AD, restoring plasma sLRP1 with recombinant LRP-IV cluster reduces brain Abeta burden and improves functional changes in cerebral blood flow (CBF) and behavioral responses, without causing neuroinflammation and/or hemorrhage. The C-terminal sequence of Abeta is required for its direct interaction with sLRP and LRP-IV cluster which is completely blocked by the receptor-associated protein (RAP) that does not directly bind Abeta. Therapies to increase LRP1 expression or reduce RAGE activity at the BBB and/or restore the peripheral Abeta 'sink' action, hold potential to reduce brain Abeta and inflammation, and improve CBF and functional recovery in AD models, and by extension in AD patients.
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Affiliation(s)
- R Deane
- Center for Neurodegenerative and Vascular Brain Disorders, University of Rochester Medical Center, 601 Elmwood Avenue, Rochester, NY 14642, USA.
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