201
|
Buccarello L, Sclip A, Sacchi M, Castaldo AM, Bertani I, ReCecconi A, Maestroni S, Zerbini G, Nucci P, Borsello T. The c-jun N-terminal kinase plays a key role in ocular degenerative changes in a mouse model of Alzheimer disease suggesting a correlation between ocular and brain pathologies. Oncotarget 2017; 8:83038-83051. [PMID: 29137322 PMCID: PMC5669948 DOI: 10.18632/oncotarget.19886] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Accepted: 07/12/2017] [Indexed: 11/25/2022] Open
Abstract
Recently a range of ocular manifestations such as retinal and lens amyloid-beta accumulation and retinal nerve fiber layer loss have been proposed as potential biomarkers in Alzheimer disease (AD). The TgCRND8 mouse model of AD exhibits age-dependent amyloid β (Aβ) oligomers accumulation and cognitive defects, amyloid plaques and hyperphosphorylated Tau deposition and inflammation. We proved the correlation between ocular pathologies and AD, observing increased levels of p-APP and p-Tau, accumulation of Aβ oligomers in the retina, eye, and optic nerve. The accumulation of amyloid markers was significantly stronger in the retinal ganglion cell (RGC) layer, suggesting that RGC might be more susceptible to degeneration. We detected a thinning of the RGC layer as well as RGC death in the retina of TgCRND8 mice, by using a combination of Optical Coherence Tomography (OCT), immunofluorescence, immunohistochemistry and Western blotting techniques. We proved for the first time the key role of C-Jun N-terminal Kinase (JNK) in the ocular degeneration. In support of this, the administration of the JNK inhibitor, D-JNKI1, was able to counteract the Aβ and p-Tau accumulation in the retina of TgCRND8 mice, and consequently reduce RGCs loss. These results confirm that degenerative changes in the retina/eye of AD mouse model mirrors the events observed in the brain parenchyma. Ocular changes can be detected by non-invasive imaging techniques, such as OCT, to study and test different therapeutic strategies against degenerative events associated to AD.
Collapse
Affiliation(s)
- Lucia Buccarello
- IRCCS-Istituto di Ricerche Farmacologiche "Mario Negri", Milan, Italy
| | - Alessandra Sclip
- IRCCS-Istituto di Ricerche Farmacologiche "Mario Negri", Milan, Italy
| | - Matteo Sacchi
- University Eye Clinic, San Giuseppe Hospital, University of Milan, Milan, Italy
| | | | - Ilaria Bertani
- IRCCS-Istituto di Ricerche Farmacologiche "Mario Negri", Milan, Italy
| | - Andrea ReCecconi
- IRCCS-Istituto di Ricerche Farmacologiche "Mario Negri", Milan, Italy
| | - Silvia Maestroni
- Unità Complicanze del Diabete, Istituto Scientifico San Raffaele, Milan, Italy
| | - Gianpaolo Zerbini
- Unità Complicanze del Diabete, Istituto Scientifico San Raffaele, Milan, Italy
| | - Paolo Nucci
- University Eye Clinic, San Giuseppe Hospital, University of Milan, Milan, Italy
| | - Tiziana Borsello
- IRCCS-Istituto di Ricerche Farmacologiche "Mario Negri", Milan, Italy.,Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| |
Collapse
|
202
|
Sasaguri H, Nilsson P, Hashimoto S, Nagata K, Saito T, De Strooper B, Hardy J, Vassar R, Winblad B, Saido TC. APP mouse models for Alzheimer's disease preclinical studies. EMBO J 2017; 36:2473-2487. [PMID: 28768718 PMCID: PMC5579350 DOI: 10.15252/embj.201797397] [Citation(s) in RCA: 454] [Impact Index Per Article: 64.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 06/09/2017] [Accepted: 07/07/2017] [Indexed: 12/11/2022] Open
Abstract
Animal models of human diseases that accurately recapitulate clinical pathology are indispensable for understanding molecular mechanisms and advancing preclinical studies. The Alzheimer's disease (AD) research community has historically used first‐generation transgenic (Tg) mouse models that overexpress proteins linked to familial AD (FAD), mutant amyloid precursor protein (APP), or APP and presenilin (PS). These mice exhibit AD pathology, but the overexpression paradigm may cause additional phenotypes unrelated to AD. Second‐generation mouse models contain humanized sequences and clinical mutations in the endogenous mouse App gene. These mice show Aβ accumulation without phenotypes related to overexpression but are not yet a clinical recapitulation of human AD. In this review, we evaluate different APP mouse models of AD, and review recent studies using the second‐generation mice. We advise AD researchers to consider the comparative strengths and limitations of each model against the scientific and therapeutic goal of a prospective preclinical study.
Collapse
Affiliation(s)
- Hiroki Sasaguri
- Laboratory for Proteolytic Neuroscience, RIKEN Brain Science Institute, Wako, Japan .,Department of Neurology and Neurological Science, Graduate School of Medicine, Tokyo Medical and Dental University, Tokyo, Japan
| | - Per Nilsson
- Laboratory for Proteolytic Neuroscience, RIKEN Brain Science Institute, Wako, Japan.,Division of Neurogeriatrics, Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Karolinska Institutet, Huddinge, Sweden
| | - Shoko Hashimoto
- Laboratory for Proteolytic Neuroscience, RIKEN Brain Science Institute, Wako, Japan
| | - Kenichi Nagata
- Laboratory for Proteolytic Neuroscience, RIKEN Brain Science Institute, Wako, Japan
| | - Takashi Saito
- Laboratory for Proteolytic Neuroscience, RIKEN Brain Science Institute, Wako, Japan.,Department of Neuroscience and Pathobiology, Research Institute of Environmental Medicine, Nagoya University, Nagoya, Japan
| | - Bart De Strooper
- Dementia Research Institute, University College London, London, UK.,Department for Neurosciences, KU Leuven, Leuven, Belgium.,VIB Center for Brain and Disease Research, Leuven, Belgium
| | - John Hardy
- Reta Lila Research Laboratories and the Department of Molecular Neuroscience, University College London Institute of Neurology, London, UK
| | - Robert Vassar
- Department of Cell and Molecular Biology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Bengt Winblad
- Division of Neurogeriatrics, Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Karolinska Institutet, Huddinge, Sweden
| | - Takaomi C Saido
- Laboratory for Proteolytic Neuroscience, RIKEN Brain Science Institute, Wako, Japan
| |
Collapse
|
203
|
The Lesion Analysis of Cholinergic Neurons in 5XFAD Mouse Model in the Three-Dimensional Level of Whole Brain. Mol Neurobiol 2017; 55:4115-4125. [PMID: 28597200 DOI: 10.1007/s12035-017-0621-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Accepted: 05/16/2017] [Indexed: 10/19/2022]
Abstract
Cholinergic system is very important for many higher brain functions, including learning and memory. Cholinergic neurons, especially those in the basal forebrain, are specifically susceptible in some neurodegenerative diseases, such as in Alzheimer's disease (AD). Here, we studied the cholinergic system lesion effects of five familial AD mutations in 5XFAD mice, a transgenic mouse model of AD. Although the cholinergic system has been studied in this mouse model, the cholinergic deficits in AD mice have never been systematically mapped in a whole-brain three-dimensional (3D) reconstruction. Using the 3D reconstruction technology combined with immunohistochemistry (3D-IHC) and design-based stereology, we comprehensively compared the differences of the cholinergic neurons and fibers between the 5XFAD mice and C57BL/6 control mice at different age. Here, we found that the lesion of cholinergic fibers occurred earlier than the cholinergic neuron loss in 5XFAD mice. The cholinergic fiber lesions in the AD mice started sequentially in amygdala, cortex, hippocampus, and then basal forebrain. However, the basal forebrain was the first brain region observed with cholinergic neuron loss at the age of 9 months in 5XFAD mice, whereas such phenomenon first occurred at the age of 15 months in C57BL/6 control mice. Moreover, using 3D reconstruction to compare the lesion of cholinergic system of aged 5XFAD and C57BL/6 control mice, it is intuitive to notice the pathologic regions and severity of lesion. Therefore, the 3D-IHC provides detailed overview of the cholinergic neurons in the whole mouse brain, which will contribute to the study of the developing and pathologic mouse brain.
Collapse
|
204
|
Yang DS, Stavrides P, Kumar A, Jiang Y, Mohan PS, Ohno M, Dobrenis K, Davidson CD, Saito M, Pawlik M, Huo C, Walkley SU, Nixon RA. Cyclodextrin has conflicting actions on autophagy flux in vivo in brains of normal and Alzheimer model mice. Hum Mol Genet 2017; 26:843-859. [PMID: 28062666 DOI: 10.1093/hmg/ddx001] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Accepted: 01/03/2016] [Indexed: 12/13/2022] Open
Abstract
2-hydroxypropyl-β-cyclodextrin (CYCLO), a modifier of cholesterol efflux from cellular membrane and endo-lysosomal compartments, reduces lysosomal lipid accumulations and has therapeutic effects in animal models of Niemann-Pick disease type C and several other neurodegenerative states. Here, we investigated CYCLO effects on autophagy in wild-type mice and TgCRND8 mice-an Alzheimer's Disease (AD) model exhibiting β-amyloidosis, neuronal autophagy deficits leading to protein and lipid accumulation within greatly enlarged autolysosomes. A 14-day intracerebroventricular administration of CYCLO to 8-month-old TgCRND8 mice that exhibit moderately advanced neuropathology markedly diminished the sizes of enlarged autolysosomes and lowered their content of GM2 ganglioside and Aβ-immunoreactivity without detectably altering amyloid precursor protein processing or extracellular Aβ/β-amyloid burden. We identified two major actions of CYCLO on autophagy underlying amelioration of lysosomal pathology. First, CYCLO stimulated lysosomal proteolytic activity by increasing cathepsin D activity, levels of cathepsins B and D and two proteins known to interact with cathepsin D, NPC1 and ABCA1. Second, CYCLO impeded autophagosome-lysosome fusion as evidenced by the accumulation of LC3, SQSTM1/p62, and ubiquitinated substrates in an expanded population of autophagosomes in the absence of greater autophagy induction. By slowing substrate delivery to lysosomes, autophagosome maturational delay, as further confirmed by our in vitro studies, may relieve lysosomal stress due to accumulated substrates. These findings provide in vivo evidence for lysosomal enhancing properties of CYCLO, but caution that prolonged interference with cellular membrane fusion/autophagosome maturation could have unfavorable consequences, which might require careful optimization of dosage and dosing schedules.
Collapse
Affiliation(s)
- Dun-Sheng Yang
- Nathan Kline Institute, Orangeburg, NY, USA.,Department of Psychiatry, New York University Langone Medical Center, New York, NY, USA
| | | | - Asok Kumar
- Nathan Kline Institute, Orangeburg, NY, USA.,Department of Psychiatry, New York University Langone Medical Center, New York, NY, USA
| | - Ying Jiang
- Nathan Kline Institute, Orangeburg, NY, USA.,Department of Psychiatry, New York University Langone Medical Center, New York, NY, USA
| | - Panaiyur S Mohan
- Nathan Kline Institute, Orangeburg, NY, USA.,Department of Psychiatry, New York University Langone Medical Center, New York, NY, USA
| | - Masuo Ohno
- Nathan Kline Institute, Orangeburg, NY, USA.,Department of Psychiatry, New York University Langone Medical Center, New York, NY, USA
| | - Kostantin Dobrenis
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Cristin D Davidson
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Mitsuo Saito
- Nathan Kline Institute, Orangeburg, NY, USA.,Department of Psychiatry, New York University Langone Medical Center, New York, NY, USA
| | | | | | - Steven U Walkley
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Ralph A Nixon
- Nathan Kline Institute, Orangeburg, NY, USA.,Department of Psychiatry, New York University Langone Medical Center, New York, NY, USA.,Cell Biology, New York University Langone Medical Center, New York, NY, USA
| |
Collapse
|
205
|
Tomlinson JJ, Shutinoski B, Dong L, Meng F, Elleithy D, Lengacher NA, Nguyen AP, Cron GO, Jiang Q, Roberson ED, Nussbaum RL, Majbour NK, El-Agnaf OM, Bennett SA, Lagace DC, Woulfe JM, Sad S, Brown EG, Schlossmacher MG. Holocranohistochemistry enables the visualization of α-synuclein expression in the murine olfactory system and discovery of its systemic anti-microbial effects. J Neural Transm (Vienna) 2017; 124:721-738. [PMID: 28477284 PMCID: PMC5446848 DOI: 10.1007/s00702-017-1726-7] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Accepted: 04/18/2017] [Indexed: 01/19/2023]
Abstract
Braak and Del Tredici have proposed that typical Parkinson disease (PD) has its origins in the olfactory bulb and gastrointestinal tract. However, the role of the olfactory system has insufficiently been explored in the pathogeneses of PD and Alzheimer disease (AD) in laboratory models. Here, we demonstrate applications of a new method to process mouse heads for microscopy by sectioning, mounting, and staining whole skulls (‘holocranohistochemistry’). This technique permits the visualization of the olfactory system from the nasal cavity to mitral cells and dopamine-producing interneurons of glomeruli in the olfactory bulb. We applied this method to two specific goals: first, to visualize PD- and AD-linked gene expression in the olfactory system, where we detected abundant, endogenous α-synuclein and tau expression in the olfactory epithelium. Furthermore, we observed amyloid-β plaques and proteinase-K-resistant α-synuclein species, respectively, in cranial nerve-I of APP- and human SNCA-over-expressing mice. The second application of the technique was to the modeling of gene–environment interactions in the nasal cavity of mice. We tracked the infection of a neurotropic respiratory-enteric-orphan virus from the nose pad into cranial nerves-I (and -V) and monitored the ensuing brain infection. Given its abundance in the olfactory epithelia, we questioned whether α-synuclein played a role in innate host defenses to modify the outcome of infections. Indeed, Snca-null mice were more likely to succumb to viral encephalitis versus their wild-type littermates. Moreover, using a bacterial sepsis model, Snca-null mice were less able to control infection after intravenous inoculation with Salmonella typhimurium. Together, holocranohistochemistry enabled new discoveries related to α-synuclein expression and its function in mice. Future studies will address: the role of Mapt and mutant SNCA alleles in infection paradigms; the contribution of xenobiotics in the initiation of idiopathic PD; and the safety to the host when systemically targeting α-synuclein by immunotherapy.
Collapse
Affiliation(s)
- Julianna J Tomlinson
- Program in Neuroscience, Ottawa Hospital Research Institute, Ottawa, ON, Canada. .,University of Ottawa Brain and Mind Research Institute, Ottawa, ON, Canada. .,University of Ottawa, 451 Smyth Road, RGH #1464, Ottawa, ON, K1H 8M5, Canada.
| | - Bojan Shutinoski
- Program in Neuroscience, Ottawa Hospital Research Institute, Ottawa, ON, Canada.,Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Li Dong
- Department of Pathology and Laboratory Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Fanyi Meng
- Program in Neuroscience, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Dina Elleithy
- Program in Neuroscience, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | | | - Angela P Nguyen
- Program in Neuroscience, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Greg O Cron
- Department of Medical Imaging, The Ottawa Hospital, Ottawa, ON, Canada.,Ottawa Hospital Research Institute, Ottawa, ON, Canada.,Faculty of Medicine, Department of Radiology, University of Ottawa, Ottawa, ON, Canada
| | - Qiubo Jiang
- Program in Neuroscience, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Erik D Roberson
- Department of Neurology, University of Alabama, Birmingham, AL, USA
| | - Robert L Nussbaum
- Division of Medical Genetics, Department of Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Nour K Majbour
- Neurological Disorders Research Center, Qatar Biomedical Research Institute, Hamad Bin Khalifa University, Qatar Foundation, Doha, Qatar
| | - Omar M El-Agnaf
- Neurological Disorders Research Center, Qatar Biomedical Research Institute, Hamad Bin Khalifa University, Qatar Foundation, Doha, Qatar
| | - Steffany A Bennett
- Program in Neuroscience, Ottawa Hospital Research Institute, Ottawa, ON, Canada.,University of Ottawa Brain and Mind Research Institute, Ottawa, ON, Canada.,Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Diane C Lagace
- Program in Neuroscience, Ottawa Hospital Research Institute, Ottawa, ON, Canada.,University of Ottawa Brain and Mind Research Institute, Ottawa, ON, Canada.,Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - John M Woulfe
- Program in Neuroscience, Ottawa Hospital Research Institute, Ottawa, ON, Canada.,University of Ottawa Brain and Mind Research Institute, Ottawa, ON, Canada.,Department of Pathology and Laboratory Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Subash Sad
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Earl G Brown
- Program in Neuroscience, Ottawa Hospital Research Institute, Ottawa, ON, Canada.,Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Michael G Schlossmacher
- Program in Neuroscience, Ottawa Hospital Research Institute, Ottawa, ON, Canada. .,University of Ottawa Brain and Mind Research Institute, Ottawa, ON, Canada. .,Division of Neurology, Department of Medicine, Faculty of Medicine, The Ottawa Hospital, Ottawa, ON, Canada. .,University of Ottawa, 451 Smyth Road, RGH #1464, Ottawa, ON, K1H 8M5, Canada.
| |
Collapse
|
206
|
Pahrudin Arrozi A, Shukri SNS, Wan Ngah WZ, Mohd Yusof YA, Ahmad Damanhuri MH, Makpol S. Evaluation of the Expression of Amyloid Precursor Protein and the Ratio of Secreted Amyloid Beta 42 to Amyloid Beta 40 in SH-SY5Y Cells Stably Transfected with Wild-Type, Single-Mutant and Double-Mutant Forms of the APP Gene for the Study of Alzheimer's Disease Pathology. Appl Biochem Biotechnol 2017; 183:853-866. [PMID: 28417423 DOI: 10.1007/s12010-017-2468-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2016] [Accepted: 03/26/2017] [Indexed: 10/19/2022]
Abstract
Neuroblastoma cell lines such as SH-SY5Y are the most frequently utilized models in neurodegenerative research, and their use has advanced the understanding of the pathology of neurodegeneration over the past few decades. In Alzheimer's disease (AD), several pathogenic mutations have been described, all of which cause elevated levels of pathological hallmarks such as amyloid-beta (Aβ). Although the genetics of Alzheimer's disease is well known, familial AD only accounts for a small number of cases in the population, with the rest being sporadic AD, which contains no known mutations. Currently, most of the in vitro models used to study AD pathogenesis only examine the level of Aβ42 as a confirmation of successful model generation and only perform comparisons between wild-type APP and single mutants of the APP gene. Recent findings have shown that the Aβ42/40 ratio in cerebrospinal fluid (CSF) is a better diagnostic indicator for AD patients than is Aβ42 alone and that more extensive Aβ formation, such as accumulation of intraneuronal Aβ, Aβ plaques, soluble oligomeric Aβ (oAβ), and insoluble fibrillar Aβ (fAβ) occurs in TgCRND8 mice expressing a double-mutant form (Swedish and Indiana) of APP, later leading to greater progressive impairment of the brain. In this study, we generated SH-SY5Y cells stably transfected separately with wild-type APP, the Swedish mutation of APP, and the Swedish and Indiana mutations of APP and evaluated the APP expression as well as the Aβ42/40 ratio in those cells. The double-mutant form of APP (Swedish/Indiana) expressed markedly high levels of APP protein and showed a high Aβ2/40 ratio compared to wild-type and single-mutant cells.
Collapse
Affiliation(s)
- Aslina Pahrudin Arrozi
- Department of Biochemistry, Faculty of Medicine, Level 17, Preclinical Building, Universiti Kebangsaan Malaysia Medical Center, Jalan Yaacob Latif, Bandar Tun Razak, Cheras, 56000, Kuala Lumpur, Malaysia
| | - Siti Nur Syazwani Shukri
- Department of Biochemistry, Faculty of Medicine, Level 17, Preclinical Building, Universiti Kebangsaan Malaysia Medical Center, Jalan Yaacob Latif, Bandar Tun Razak, Cheras, 56000, Kuala Lumpur, Malaysia
| | - Wan Zurinah Wan Ngah
- Department of Biochemistry, Faculty of Medicine, Level 17, Preclinical Building, Universiti Kebangsaan Malaysia Medical Center, Jalan Yaacob Latif, Bandar Tun Razak, Cheras, 56000, Kuala Lumpur, Malaysia
| | - Yasmin Anum Mohd Yusof
- Department of Biochemistry, Faculty of Medicine, Level 17, Preclinical Building, Universiti Kebangsaan Malaysia Medical Center, Jalan Yaacob Latif, Bandar Tun Razak, Cheras, 56000, Kuala Lumpur, Malaysia
| | - Mohd Hanafi Ahmad Damanhuri
- Department of Biochemistry, Faculty of Medicine, Level 17, Preclinical Building, Universiti Kebangsaan Malaysia Medical Center, Jalan Yaacob Latif, Bandar Tun Razak, Cheras, 56000, Kuala Lumpur, Malaysia
| | - Suzana Makpol
- Department of Biochemistry, Faculty of Medicine, Level 17, Preclinical Building, Universiti Kebangsaan Malaysia Medical Center, Jalan Yaacob Latif, Bandar Tun Razak, Cheras, 56000, Kuala Lumpur, Malaysia.
| |
Collapse
|
207
|
Shinohara M, Tachibana M, Kanekiyo T, Bu G. Role of LRP1 in the pathogenesis of Alzheimer's disease: evidence from clinical and preclinical studies. J Lipid Res 2017; 58:1267-1281. [PMID: 28381441 DOI: 10.1194/jlr.r075796] [Citation(s) in RCA: 169] [Impact Index Per Article: 24.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Revised: 04/02/2017] [Indexed: 12/16/2022] Open
Abstract
Among the LDL receptor (LDLR) family members, the roles of LDLR-related protein (LRP)1 in the pathogenesis of Alzheimer's disease (AD), especially late-onset AD, have been the most studied by genetic, neuropathological, and biomarker analyses (clinical studies) or cellular and animal model systems (preclinical studies) over the last 25 years. Although there are some conflicting reports, accumulating evidence from preclinical studies indicates that LRP1 not only regulates the metabolism of amyloid-β peptides (Aβs) in the brain and periphery, but also maintains brain homeostasis, impairment of which likely contributes to AD development in Aβ-independent manners. Several preclinical studies have also demonstrated an involvement of LRP1 in regulating the pathogenic role of apoE, whose gene is the strongest genetic risk factor for AD. Nonetheless, evidence from clinical studies is not sufficient to conclude how LRP1 contributes to AD development. Thus, despite very promising results from preclinical studies, the role of LRP1 in AD pathogenesis remains to be further clarified. In this review, we discuss the potential mechanisms underlying how LRP1 affects AD pathogenesis through Aβ-dependent and -independent pathways by reviewing both clinical and preclinical studies. We also discuss potential therapeutic strategies for AD by targeting LRP1.
Collapse
Affiliation(s)
| | | | | | - Guojun Bu
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL
| |
Collapse
|
208
|
Li W, Xu Z, Xu B, Chan CY, Lin X, Wang Y, Chen G, Wang Z, Yuan Q, Zhu G, Sun H, Wu W, Shi P. Investigation of the Subcellular Neurotoxicity of Amyloid-β Using a Device Integrating Microfluidic Perfusion and Chemotactic Guidance. Adv Healthc Mater 2017; 6. [PMID: 28121396 DOI: 10.1002/adhm.201600895] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 11/28/2016] [Indexed: 11/10/2022]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder with the histopathological hallmark of extracellular accumulation of amyloid-β (Aβ) peptide in brain senile plaques. Though many studies have shown the neural toxicity from various forms of Aβ peptides, the subcellular mechanisms of Aβ peptide are still not well understood, partially due to the technical challenges of isolating axons or dendrites from the cell body for localized investigation. In this study, the subcellular toxicity and localization of Aβ peptides are investigated by utilizing a microfluidic compartmentalized device, which combines physical restriction and chemotactic guidance to enable the isolation of axons and dendrites for localized pharmacological studies. It is found that Aβ peptides induced neuronal death is mostly resulted from Aβ treatment at cell body or axonal processes, but not at dendritic neurites. Simply applying Aβ to axons alone induces significant hyperactive spiking activity. Dynamic transport of Aβ aggregates is only observed between axon terminal and cell body. In addition to differential cellular uptake, more Aβ-peptide secretion is detected significantly from axons than from dendritic side. These results clearly demonstrate the existence of a localized mechanism in Aβ-induced neurotoxicity, and can potentially benefit the development of new therapeutic strategies for AD.
Collapse
Affiliation(s)
- Wei Li
- Department of Mechanical and Biomedical Engineering; City University of Hong Kong; 83 Tat Chee Ave Kowloon Hong Kong SAR 999077 China
| | - Zhen Xu
- Department of Mechanical and Biomedical Engineering; City University of Hong Kong; 83 Tat Chee Ave Kowloon Hong Kong SAR 999077 China
| | - Bingzhe Xu
- Department of Mechanical and Biomedical Engineering; City University of Hong Kong; 83 Tat Chee Ave Kowloon Hong Kong SAR 999077 China
| | - Chung Yuen Chan
- Department of Mechanical and Biomedical Engineering; City University of Hong Kong; 83 Tat Chee Ave Kowloon Hong Kong SAR 999077 China
| | - Xudong Lin
- Department of Mechanical and Biomedical Engineering; City University of Hong Kong; 83 Tat Chee Ave Kowloon Hong Kong SAR 999077 China
| | - Ying Wang
- Department of Mechanical and Biomedical Engineering; City University of Hong Kong; 83 Tat Chee Ave Kowloon Hong Kong SAR 999077 China
| | - Ganchao Chen
- Department of Biology and Chemistry; City University of Hong Kong; 83 Tat Chee Ave Kowloon Hong Kong SAR 999077 China
| | - Zhigang Wang
- Department of Biology and Chemistry; City University of Hong Kong; 83 Tat Chee Ave Kowloon Hong Kong SAR 999077 China
| | - Qiuju Yuan
- School of Chinese Medicine; Faculty of Science; The Chinese University of Hong Kong; Shatin, Hong Kong SAR 999077 China
| | - Guangyu Zhu
- Department of Biology and Chemistry; City University of Hong Kong; 83 Tat Chee Ave Kowloon Hong Kong SAR 999077 China
| | - Hongyan Sun
- Department of Biology and Chemistry; City University of Hong Kong; 83 Tat Chee Ave Kowloon Hong Kong SAR 999077 China
| | - Wutian Wu
- Department of Anatomy; The University of Hong Kong; 21 Sassoon Road Hong Kong SAR 999077 China
| | - Peng Shi
- Department of Mechanical and Biomedical Engineering; City University of Hong Kong; 83 Tat Chee Ave Kowloon Hong Kong SAR 999077 China
- Shenzhen Research Institute; City University of Hong Kong; Shenzhen 518057 P. R. China
| |
Collapse
|
209
|
Moutinho M, Landreth GE. Therapeutic potential of nuclear receptor agonists in Alzheimer's disease. J Lipid Res 2017; 58:1937-1949. [PMID: 28264880 DOI: 10.1194/jlr.r075556] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 03/03/2017] [Indexed: 11/20/2022] Open
Abstract
Alzheimer's disease (AD) is characterized by an extensive accumulation of amyloid-β (Aβ) peptide, which triggers a set of deleterious processes, including synaptic dysfunction, inflammation, and neuronal injury, leading to neuronal loss and cognitive impairment. A large body of evidence supports that nuclear receptor (NR) activation could be a promising therapeutic approach for AD. NRs are ligand-activated transcription factors that regulate gene expression and have cell type-specific effects. In this review, we discuss the mechanisms that underlie the beneficial effects of NRs in AD. Moreover, we summarize studies reported in the last 10-15 years and their major outcomes arising from the pharmacological targeting of NRs in AD animal models. The dissection of the pathways regulated by NRs in the context of AD is of importance in identifying novel and effective therapeutic strategies.
Collapse
Affiliation(s)
- Miguel Moutinho
- Department of Neurosciences, Case Western Reserve University, Cleveland, OH 44106 and Stark Neuroscience Research Institute, Indiana University School of Medicine, Indianapolis, IN 46202
| | - Gary E Landreth
- Department of Neurosciences, Case Western Reserve University, Cleveland, OH 44106 and Stark Neuroscience Research Institute, Indiana University School of Medicine, Indianapolis, IN 46202
| |
Collapse
|
210
|
Yin J, Zhao F, Chojnacki JE, Fulp J, Klein WL, Zhang S, Zhu X. NLRP3 Inflammasome Inhibitor Ameliorates Amyloid Pathology in a Mouse Model of Alzheimer's Disease. Mol Neurobiol 2017; 55:1977-1987. [PMID: 28255908 DOI: 10.1007/s12035-017-0467-9] [Citation(s) in RCA: 143] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 02/20/2017] [Indexed: 12/25/2022]
Abstract
The activation of the NLRP3 inflammasome signaling pathway plays an important role in the neuroinflammation in Alzheimer's disease (AD). In this study, we investigated the effects of JC-124, a rationally designed NLRP3 inflammasome inhibitor, on AD-related deficits in CRND8 APP transgenic mice (TgCRND8). We first demonstrated increased formation and activation of NLRP3 inflammasome in TgCRND8 mice compared to non-transgenic littermate controls, which was inhibited by the treatment with JC-124. Importantly, JC-124 treatment led to decreased levels of Aβ deposition and decreased levels of soluble and insoluble Aβ1-42 in the brain of CRND8 mice which was accompanied by reduced β-cleavage of APP, reduced activation of microglia but enhanced astrocytosis. Oxidative stress was decreased and synaptophysin was increased in the CRND8 mice after JC-124 treatment, demonstrating a neuroprotective effect. Overall, these data demonstrated beneficial effects of JC-124 as a specific NLRP3 inflammasome inhibitor in AD mouse model and supported the further development of NLRP3 inflammasome inhibitors as a viable option for AD therapeutics.
Collapse
Affiliation(s)
- Jun Yin
- Department of Pathophysiology, School of Basic Medical Sciences, Wuhan University, Wuhan, Hubei, China.,Department of Pathology, Case Western Reserve University, Cleveland, OH, USA
| | - Fanpeng Zhao
- Department of Pathology, Case Western Reserve University, Cleveland, OH, USA
| | - Jeremy E Chojnacki
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, VA, 23298, USA
| | - Jacob Fulp
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, VA, 23298, USA
| | - William L Klein
- Department of Neurobiology, Northwestern University, Evanston, IL, USA
| | - Shijun Zhang
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, VA, 23298, USA.
| | - Xiongwei Zhu
- Department of Pathology, Case Western Reserve University, Cleveland, OH, USA.
| |
Collapse
|
211
|
Depletion of coagulation factor XII ameliorates brain pathology and cognitive impairment in Alzheimer disease mice. Blood 2017; 129:2547-2556. [PMID: 28242605 DOI: 10.1182/blood-2016-11-753202] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Accepted: 02/21/2017] [Indexed: 12/21/2022] Open
Abstract
Vascular abnormalities and inflammation are found in many Alzheimer disease (AD) patients, but whether these changes play a causative role in AD is not clear. The factor XII (FXII) -initiated contact system can trigger both vascular pathology and inflammation and is activated in AD patients and AD mice. We have investigated the role of the contact system in AD pathogenesis. Cleavage of high-molecular-weight kininogen (HK), a marker for activation of the inflammatory arm of the contact system, is increased in a mouse model of AD, and this cleavage is temporally correlated with the onset of brain inflammation. Depletion of FXII in AD mice inhibited HK cleavage in plasma and reduced neuroinflammation, fibrinogen deposition, and neurodegeneration in the brain. Moreover, FXII-depleted AD mice showed better cognitive function than untreated AD mice. These results indicate that FXII-mediated contact system activation contributes to AD pathogenesis, and therefore this system may offer novel targets for AD treatment.
Collapse
|
212
|
Hamm V, Héraud C, Bott JB, Herbeaux K, Strittmatter C, Mathis C, Goutagny R. Differential contribution of APP metabolites to early cognitive deficits in a TgCRND8 mouse model of Alzheimer's disease. SCIENCE ADVANCES 2017; 3:e1601068. [PMID: 28275722 PMCID: PMC5325539 DOI: 10.1126/sciadv.1601068] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Accepted: 01/25/2017] [Indexed: 06/06/2023]
Abstract
Alzheimer's disease (AD) is a neurodegenerative pathology commonly characterized by a progressive and irreversible deterioration of cognitive functions, especially memory. Although the etiology of AD remains unknown, a consensus has emerged on the amyloid hypothesis, which posits that increased production of soluble amyloid β (Aβ) peptide induces neuronal network dysfunctions and cognitive deficits. However, the relative failures of Aβ-centric therapeutics suggest that the amyloid hypothesis is incomplete and/or that the treatments were given too late in the course of AD, when neuronal damages were already too extensive. Hence, it is striking to see that very few studies have extensively characterized, from anatomy to behavior, the alterations associated with pre-amyloid stages in mouse models of AD amyloid pathology. To fulfill this gap, we examined memory capacities as well as hippocampal network anatomy and dynamics in young adult pre-plaque TgCRND8 mice when hippocampal Aβ levels are still low. We showed that TgCRND8 mice present alterations in hippocampal inhibitory networks and γ oscillations at this stage. Further, these mice exhibited deficits only in a subset of hippocampal-dependent memory tasks, which are all affected at later stages. Last, using a pharmacological approach, we showed that some of these early memory deficits were Aβ-independent. Our results could partly explain the limited efficacy of Aβ-directed treatments and favor multitherapy approaches for early symptomatic treatment for AD.
Collapse
Affiliation(s)
- Valentine Hamm
- Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), Université de Strasbourg, Faculté de Psychologie, 12 rue Goethe, F-67000 Strasbourg, France
- LNCA, UMR 7364, CNRS, Neuropôle de Strasbourg, 12 rue Goethe, F-67000 Strasbourg, France
| | - Céline Héraud
- Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), Université de Strasbourg, Faculté de Psychologie, 12 rue Goethe, F-67000 Strasbourg, France
- LNCA, UMR 7364, CNRS, Neuropôle de Strasbourg, 12 rue Goethe, F-67000 Strasbourg, France
| | - Jean-Bastien Bott
- Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), Université de Strasbourg, Faculté de Psychologie, 12 rue Goethe, F-67000 Strasbourg, France
- LNCA, UMR 7364, CNRS, Neuropôle de Strasbourg, 12 rue Goethe, F-67000 Strasbourg, France
| | - Karine Herbeaux
- Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), Université de Strasbourg, Faculté de Psychologie, 12 rue Goethe, F-67000 Strasbourg, France
- LNCA, UMR 7364, CNRS, Neuropôle de Strasbourg, 12 rue Goethe, F-67000 Strasbourg, France
| | - Carole Strittmatter
- Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), Université de Strasbourg, Faculté de Psychologie, 12 rue Goethe, F-67000 Strasbourg, France
- LNCA, UMR 7364, CNRS, Neuropôle de Strasbourg, 12 rue Goethe, F-67000 Strasbourg, France
| | - Chantal Mathis
- Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), Université de Strasbourg, Faculté de Psychologie, 12 rue Goethe, F-67000 Strasbourg, France
- LNCA, UMR 7364, CNRS, Neuropôle de Strasbourg, 12 rue Goethe, F-67000 Strasbourg, France
| | - Romain Goutagny
- Laboratoire de Neurosciences Cognitives et Adaptatives (LNCA), Université de Strasbourg, Faculté de Psychologie, 12 rue Goethe, F-67000 Strasbourg, France
- LNCA, UMR 7364, CNRS, Neuropôle de Strasbourg, 12 rue Goethe, F-67000 Strasbourg, France
| |
Collapse
|
213
|
Mahar I, Albuquerque MS, Mondragon-Rodriguez S, Cavanagh C, Davoli MA, Chabot JG, Williams S, Mechawar N, Quirion R, Krantic S. Phenotypic Alterations in Hippocampal NPY- and PV-Expressing Interneurons in a Presymptomatic Transgenic Mouse Model of Alzheimer's Disease. Front Aging Neurosci 2017; 8:327. [PMID: 28154533 PMCID: PMC5243860 DOI: 10.3389/fnagi.2016.00327] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Accepted: 12/19/2016] [Indexed: 11/21/2022] Open
Abstract
Interneurons, key regulators of hippocampal neuronal network excitability and synchronization, are lost in advanced stages of Alzheimer’s disease (AD). Given that network changes occur at early (presymptomatic) stages, we explored whether alterations of interneurons also occur before amyloid-beta (Aβ) accumulation. Numbers of neuropeptide Y (NPY) and parvalbumin (PV) immunoreactive (IR) cells were decreased in the hippocampus of 1 month-old TgCRND8 mouse AD model in a sub-regionally specific manner. The most prominent change observed was a decrease in the number of PV-IR cells that selectively affected CA1/2 and subiculum, with the pyramidal layer (PY) of CA1/2 accounting almost entirely for the reduction in number of hippocampal PV-IR cells. As PV neurons were decreased selectively in CA1/2 and subiculum, and given that they are critically involved in the control of hippocampal theta oscillations, we then assessed intrinsic theta oscillations in these regions after a 4-aminopyridine (4AP) challenge. This revealed increased theta power and population bursts in TgCRND8 mice compared to non-transgenic (nTg) controls, suggesting a hyperexcitability network state. Taken together, our results identify for the first time AD-related alterations in hippocampal interneuron function as early as at 1 month of age. These early functional alterations occurring before amyloid deposition may contribute to cognitive dysfunction in AD.
Collapse
Affiliation(s)
- Ian Mahar
- Douglas Mental Health University InstituteVerdun, QC, Canada; McGill Group for Suicide Studies, Douglas Mental Health University InstituteVerdun, QC, Canada; Integrated Program in Neuroscience, McGill UniversityMontreal, QC, Canada
| | - Marilia Silva Albuquerque
- Douglas Mental Health University InstituteVerdun, QC, Canada; Laboratory of Biomedicine and Biotechnology, School of Arts, Sciences and Humanities, Universidade de São PauloSão Paulo, Brazil; Graduation Course on Pharmacology, Institute of Biomedical Sciences, Universidade de São PauloSão Paulo, Brazil; Research Group on Neuropharmacology of AgingSão Paulo, Brazil
| | - Siddhartha Mondragon-Rodriguez
- Douglas Mental Health University InstituteVerdun, QC, Canada; CONACYT National Council for Science and TechnologyMéxico city, Mexico; UNAM Developmental Neurobiology and Neurophysiology, Institute of Neurobiology, National Autonomous University of MéxicoQuerétaro, Mexico
| | - Chelsea Cavanagh
- Douglas Mental Health University InstituteVerdun, QC, Canada; Integrated Program in Neuroscience, McGill UniversityMontreal, QC, Canada
| | - Maria Antonietta Davoli
- Douglas Mental Health University InstituteVerdun, QC, Canada; McGill Group for Suicide Studies, Douglas Mental Health University InstituteVerdun, QC, Canada
| | - Jean-Guy Chabot
- Douglas Mental Health University InstituteVerdun, QC, Canada; Integrated Program in Neuroscience, McGill UniversityMontreal, QC, Canada
| | - Sylvain Williams
- Douglas Mental Health University InstituteVerdun, QC, Canada; Integrated Program in Neuroscience, McGill UniversityMontreal, QC, Canada
| | - Naguib Mechawar
- Douglas Mental Health University InstituteVerdun, QC, Canada; McGill Group for Suicide Studies, Douglas Mental Health University InstituteVerdun, QC, Canada; Integrated Program in Neuroscience, McGill UniversityMontreal, QC, Canada
| | - Rémi Quirion
- Douglas Mental Health University InstituteVerdun, QC, Canada; Integrated Program in Neuroscience, McGill UniversityMontreal, QC, Canada
| | - Slavica Krantic
- Douglas Mental Health University InstituteVerdun, QC, Canada; Integrated Program in Neuroscience, McGill UniversityMontreal, QC, Canada; Centre de Recherche des Cordeliers, Sorbonne Universités, UPMC Univ Paris 06, INSERM, Université Paris Descartes, Sorbonne Paris Cité, UMR_S 1138Paris, France
| |
Collapse
|
214
|
Strain-specific Fibril Propagation by an Aβ Dodecamer. Sci Rep 2017; 7:40787. [PMID: 28098204 PMCID: PMC5241678 DOI: 10.1038/srep40787] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Accepted: 12/09/2016] [Indexed: 01/12/2023] Open
Abstract
Low molecular weight oligomers of amyloid-β (Aβ) have emerged as the primary toxic agents in the etiology of Alzheimer disease (AD). Polymorphism observed within the aggregation end products of fibrils are known to arise due to microstructural differences among the oligomers. Diversity in aggregate morphology correlates with the differences in AD, cementing the idea that conformational strains of oligomers could be significant in phenotypic outcomes. Therefore, it is imperative to determine the ability of strains to faithfully propagate their structure. Here we report fibril propagation of an Aβ42 dodecamer called large fatty acid-derived oligomers (LFAOs). The LFAO oligomeric strain selectively induces acute cerebral amyloid angiopathy (CAA) in neonatally-injected transgenic CRND8 mice. Propagation in-vitro occurs as a three-step process involving the association of LFAO units. LFAO-seeded fibrils possess distinct morphology made of repeating LFAO units that could be regenerated upon sonication. Overall, these data bring forth an important mechanistic perspective into strain-specific propagation of oligomers that has remained elusive thus far.
Collapse
|
215
|
Ishizuka Y, Hanamura K. Drebrin in Alzheimer’s Disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 1006:203-223. [DOI: 10.1007/978-4-431-56550-5_12] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
|
216
|
Soudy R, Patel A, Fu W, Kaur K, MacTavish D, Westaway D, Davey R, Zajac J, Jhamandas J. Cyclic AC253, a novel amylin receptor antagonist, improves cognitive deficits in a mouse model of Alzheimer's disease. ALZHEIMER'S & DEMENTIA (NEW YORK, N. Y.) 2017; 3:44-56. [PMID: 29067318 PMCID: PMC5651374 DOI: 10.1016/j.trci.2016.11.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
INTRODUCTION Amylin receptor serves as a portal for the expression of deleterious effects of amyloid β-protein (Aβ), a key pathologic hallmark of Alzheimer's disease. Previously, we showed that AC253, an amylin receptor antagonist, is neuroprotective against Aβ toxicity in vitro and abrogates Aβ-induced impairment of hippocampal long-term potentiation. METHODS Amyloid precursor protein-overexpressing TgCRND8 mice received intracerebroventricularly AC253 for 5 months. New cyclized peptide cAC253 was synthesized and administered intraperitoneally three times a week for 10 weeks in the same mouse model. Cognitive functions were monitored, and pathologic changes were quantified biochemically and immunohistochemically. RESULTS AC253, when administered intracerebroventricularly, improves spatial memory and learning, increases synaptic integrity, reduces microglial activation without discernible adverse effects in TgCRND8 mice. cAC253 demonstrates superior brain permeability, better proteolytic stability, and enhanced binding affinity to brain amylin receptors after a single intraperitoneal injection. Furthermore, cAC253 administered intraperitoneally also demonstrates improvement in spatial memory in TgCRND8 mice. DISCUSSION Amylin receptor is a therapeutic target for Alzheimer's disease and represents a disease-modifying therapy for this condition.
Collapse
Affiliation(s)
- Rania Soudy
- Department of Medicine (Neurology), Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
- Faculty of Pharmacy, Cairo University, Cairo, Egypt
| | - Aarti Patel
- Department of Medicine (Neurology), Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Wen Fu
- Department of Medicine (Neurology), Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Kamaljit Kaur
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada
- Chapman University School of Pharmacy, Irvine, California, USA
| | - David MacTavish
- Department of Medicine (Neurology), Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
| | - David Westaway
- Department of Medicine (Neurology), Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - Rachel Davey
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria, Australia
| | - Jeffrey Zajac
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria, Australia
| | - Jack Jhamandas
- Department of Medicine (Neurology), Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
| |
Collapse
|
217
|
Brown AM, Bevan DR. Influence of sequence and lipid type on membrane perturbation by human and rat amyloid β-peptide (1–42). Arch Biochem Biophys 2017; 614:1-13. [DOI: 10.1016/j.abb.2016.11.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 11/17/2016] [Accepted: 11/20/2016] [Indexed: 12/20/2022]
|
218
|
Solé-Domènech S, Cruz DL, Capetillo-Zarate E, Maxfield FR. The endocytic pathway in microglia during health, aging and Alzheimer's disease. Ageing Res Rev 2016; 32:89-103. [PMID: 27421577 DOI: 10.1016/j.arr.2016.07.002] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 07/01/2016] [Accepted: 07/05/2016] [Indexed: 12/14/2022]
Abstract
Microglia, the main phagocytes of the central nervous system (CNS), are involved in the surveillance and maintenance of nervous tissue. During normal tissue homeostasis, microglia migrates within the CNS, phagocytose dead cells and tissue debris, and modulate synapse pruning and spine formation via controlled phagocytosis. In the event of an invasion by a foreign body, microglia are able to phagocytose the invading pathogen and process it proteolytically for antigen presentation. Internalized substrates are incorporated and sorted within the endocytic pathway and thereafter transported via complex vesicular routes. When targeted for degradation, substrates are delivered to acidic late endosomes and lysosomes. In these, the enzymatic degradation relies on pH and enzyme content. Endocytosis, sorting, transport, compartment acidification and degradation are regulated by complex signaling mechanisms, and these may be altered during aging and pathology. In this review, we discuss the endocytic pathway in microglia, with insight into the mechanisms controlling lysosomal biogenesis and pH regulation. We also discuss microglial lysosome function associated with Alzheimer's disease (AD) and the mechanisms of amyloid-beta (Aβ) internalization and degradation. Finally, we explore some therapies currently being investigated to treat AD and their effects on microglial response to Aβ, with insight in those involving enhancement of lysosomal function.
Collapse
|
219
|
Sexually Dimorphic Expression of Reelin in the Brain of a Mouse Model of Alzheimer Disease. J Mol Neurosci 2016; 61:359-367. [PMID: 27866325 DOI: 10.1007/s12031-016-0865-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Accepted: 11/11/2016] [Indexed: 10/20/2022]
Abstract
Recent evidence highlights the protective role of reelin against amyloid β (Aβ)-induced synaptic dysfunction and cognitive impairment in Alzheimer disease (AD). In this study, exploiting TgCRND8 mice that overexpress a mutant form of amyloid β precursor protein (AβPP) and display an early onset of AD neuropathological signs, we addressed the question whether changes of reelin expression eventually precede the appearance of Aβ-plaques in a sex-dependent manner. We show that sex-associated and brain region-specific differences in reelin expression appear long before Aβ-plaque formation. However, in spite of a downregulation of reelin expression compared to males, TgCRND8 females display fewer Aβ-plaques, suggesting that additional factors, other than sex and reelin level, influence amyloidosis in this mouse model.
Collapse
|
220
|
Sankowski R, Herring A, Keyvani K, Frenzel K, Wu J, Röskam S, Noelker C, Bacher M, Al-Abed Y. The multi-target effects of CNI-1493: convergence of anti-amylodogenic and anti-inflammatory properties in animal models of Alzheimer's disease. Mol Med 2016; 22:776-788. [PMID: 27847962 DOI: 10.2119/molmed.2016.00163] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Accepted: 10/20/2016] [Indexed: 12/25/2022] Open
Abstract
After several decades of Alzheimer's disease (AD) research and failed clinical trials, one can speculate that targeting a single pathway is not sufficient. However, a cocktail of novel therapeutics will constitute a challenging clinical trial. A more plausible approach will capitalize on a drug that has relevant and synergistic multiple-target effects in AD. We have previously demonstrated the efficacy of CNI-1493 in the CRND8 transgenic AD mouse model. Similar to many anti-inflammatory drugs that were tested in preclinical model of AD, it was speculated that the significant effect of CNI-1493 is due to its established anti-inflammatory properties in rodents and humans. In the present study, we set out to elucidate the protective mechanism of CNI-1493 as a drug simultaneously targeting several aspects of AD pathology. Using C1213, a highly similar analogue of CNI-1493 that lacks anti-inflammatory properties, we show that both compounds directly interact with soluble and insoluble Amyloid β (Aβ) aggregates and attenuate Aβ cytotoxicity in vitro. Additionally, CNI-1493 and C1213 ameliorated Aβ-induced behavioral deficits in nematodes. Finally, C1213 reduced Aβ plaque burden and cognitive deficits in transgenic CRND8 mice to a similar extent as previously shown with CNI-1493. Taken together, our findings suggest anti-amyloidogenic activity as a relevant component for the in-vivo efficacy of CNI-1493 and its analogue C1213. Thus, CNI-1493, a drug with proven safety in humans, is a viable candidate for novel multi-target therapeutic approaches to AD.
Collapse
Affiliation(s)
- Roman Sankowski
- Center for Molecular Innovation, The Feinstein Institute for Medical Research, 350 Community drive, Manhasset, NY 11030 USA.,Elmezzi Graduate School of Molecular Medicine, The Feinstein Institute for Medical Research, 350 Community drive, Manhasset, NY, 11030, USA
| | - Arne Herring
- Institute of Neuropathology, University of Duisburg-Essen, Hufelandstr. 55, 45122 Essen, Germany
| | - Kathy Keyvani
- Institute of Neuropathology, University of Duisburg-Essen, Hufelandstr. 55, 45122 Essen, Germany
| | - Kathrin Frenzel
- Institute of Neuropathology, University of Freiburg, Breisacherstraße 64, D-79106 Freiburg Germany
| | - Jinyu Wu
- Center for Molecular Innovation, The Feinstein Institute for Medical Research, 350 Community drive, Manhasset, NY 11030 USA
| | - Stephan Röskam
- Institute of Medical Sociology and Social Medicine, Philipps-University of Marburg, Karl-von-Frisch-Str. 8, 35043 Marburg, Germany
| | - Carmen Noelker
- Department of Neurology, Faculty of Medicine, Philipps-University, Baldingerstraße, 35043 Marburg, Germany
| | - Michael Bacher
- Institute of Immunology, Philipps-University Marburg, Hans-Meerwein-Str., 35043 Marburg, Germany
| | - Yousef Al-Abed
- Center for Molecular Innovation, The Feinstein Institute for Medical Research, 350 Community drive, Manhasset, NY 11030 USA
| |
Collapse
|
221
|
Snow WM, Albensi BC. Neuronal Gene Targets of NF-κB and Their Dysregulation in Alzheimer's Disease. Front Mol Neurosci 2016; 9:118. [PMID: 27881951 PMCID: PMC5101203 DOI: 10.3389/fnmol.2016.00118] [Citation(s) in RCA: 107] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Accepted: 10/25/2016] [Indexed: 11/21/2022] Open
Abstract
Although, better known for its role in inflammation, the transcription factor nuclear factor kappa B (NF-κB) has more recently been implicated in synaptic plasticity, learning, and memory. This has been, in part, to the discovery of its localization not just in glia, cells that are integral to mediating the inflammatory process in the brain, but also neurons. Several effectors of neuronal NF-κB have been identified, including calcium, inflammatory cytokines (i.e., tumor necrosis factor alpha), and the induction of experimental paradigms thought to reflect learning and memory at the cellular level (i.e., long-term potentiation). NF-κB is also activated after learning and memory formation in vivo. In turn, activation of NF-κB can elicit either suppression or activation of other genes. Studies are only beginning to elucidate the multitude of neuronal gene targets of NF-κB in the normal brain, but research to date has confirmed targets involved in a wide array of cellular processes, including cell signaling and growth, neurotransmission, redox signaling, and gene regulation. Further, several lines of research confirm dysregulation of NF-κB in Alzheimer's disease (AD), a disorder characterized clinically by a profound deficit in the ability to form new memories. AD-related neuropathology includes the characteristic amyloid beta plaque formation and neurofibrillary tangles. Although, such neuropathological findings have been hypothesized to contribute to memory deficits in AD, research has identified perturbations at the cellular and synaptic level that occur even prior to more gross pathologies, including transcriptional dysregulation. Indeed, synaptic disturbances appear to be a significant correlate of cognitive deficits in AD. Given the more recently identified role for NF-κB in memory and synaptic transmission in the normal brain, the expansive network of gene targets of NF-κB, and its dysregulation in AD, a thorough understanding of NF-κB-related signaling in AD is warranted and may have important implications for uncovering treatments for the disease. This review aims to provide a comprehensive view of our current understanding of the gene targets of this transcription factor in neurons in the intact brain and provide an overview of studies investigating NF-κB signaling, including its downstream targets, in the AD brain as a means of uncovering the basic physiological mechanisms by which memory becomes fragile in the disease.
Collapse
Affiliation(s)
- Wanda M Snow
- Division of Neurodegenerative Disorders, St. Boniface Hospital ResearchWinnipeg, MB, Canada; Department of Pharmacology and Therapeutics, University of ManitobaWinnipeg, MB, Canada
| | - Benedict C Albensi
- Division of Neurodegenerative Disorders, St. Boniface Hospital ResearchWinnipeg, MB, Canada; Department of Pharmacology and Therapeutics, University of ManitobaWinnipeg, MB, Canada
| |
Collapse
|
222
|
Misassembly of full-length Disrupted-in-Schizophrenia 1 protein is linked to altered dopamine homeostasis and behavioral deficits. Mol Psychiatry 2016; 21:1561-1572. [PMID: 26754951 PMCID: PMC5078859 DOI: 10.1038/mp.2015.194] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Revised: 10/16/2015] [Accepted: 10/22/2015] [Indexed: 12/21/2022]
Abstract
Disrupted-in-schizophrenia 1 (DISC1) is a mental illness gene first identified in a Scottish pedigree. So far, DISC1-dependent phenotypes in animal models have been confined to expressing mutant DISC1. Here we investigated how pathology of full-length DISC1 protein could be a major mechanism in sporadic mental illness. We demonstrate that a novel transgenic rat model, modestly overexpressing the full-length DISC1 transgene, showed phenotypes consistent with a significant role of DISC1 misassembly in mental illness. The tgDISC1 rat displayed mainly perinuclear DISC1 aggregates in neurons. Furthermore, the tgDISC1 rat showed a robust signature of behavioral phenotypes that includes amphetamine supersensitivity, hyperexploratory behavior and rotarod deficits, all pointing to changes in dopamine (DA) neurotransmission. To understand the etiology of the behavioral deficits, we undertook a series of molecular studies in the dorsal striatum of tgDISC1 rats. We observed an 80% increase in high-affinity DA D2 receptors, an increased translocation of the dopamine transporter to the plasma membrane and a corresponding increase in DA inflow as observed by cyclic voltammetry. A reciprocal relationship between DISC1 protein assembly and DA homeostasis was corroborated by in vitro studies. Elevated cytosolic dopamine caused an increase in DISC1 multimerization, insolubility and complexing with the dopamine transporter, suggesting a physiological mechanism linking DISC1 assembly and dopamine homeostasis. DISC1 protein pathology and its interaction with dopamine homeostasis is a novel cellular mechanism that is relevant for behavioral control and may have a role in mental illness.
Collapse
|
223
|
Morrone CD, Thomason LAM, Brown ME, Aubert I, McLaurin J. Effects of Neurotrophic Support and Amyloid-Targeted Combined Therapy on Adult Hippocampal Neurogenesis in a Transgenic Model of Alzheimer's Disease. PLoS One 2016; 11:e0165393. [PMID: 27768761 PMCID: PMC5074589 DOI: 10.1371/journal.pone.0165393] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 10/11/2016] [Indexed: 12/29/2022] Open
Abstract
Although it is recognized that multi-drug therapies may be necessary to combat AD, there is a paucity of preclinical proof of concept studies. We present a combination treatment paradigm, which temporally affects different aspects of Alzheimer's disease (AD)-like pathology, specifically Aβ-toxicity and neurogenesis. At early stages of AD-like pathology, in TgCRND8 mice, we found that combating Aβ pathology with scyllo-inositol ameliorated deficits in neurogenesis. Older TgCRND8 mice with established amyloid load had decreased progenitor cell proliferation and survival compared to non-transgenic mice, regardless of scyllo-inositol treatment. The prolonged exposure to Aβ-pathology leads to deficits in the neurogenic niche, thus targeting Aβ alone is insufficient to rescue neurogenesis. To support the neurogenic niche, we combined scyllo-inositol treatment with leteprinim potassium (neotrofin), the latter of which stimulates neurotrophin expression. We show that the combination treatment of scyllo-inositol and neotrofin enhances neuronal survival and differentiation. We propose this proof of concept combination therapy of targeting Aβ-pathology and neurotrophin deficits as a potential treatment for AD.
Collapse
Affiliation(s)
- Christopher D Morrone
- Biological Sciences, Sunnybrook Research Institute, M4N 3M5, Toronto, ON, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, M5S 1A8, Toronto, ON, Canada
| | - Lynsie A M Thomason
- Physical Sciences, Sunnybrook Research Institute, M4N 3M5, Toronto, ON, Canada
| | - Mary E Brown
- Biological Sciences, Sunnybrook Research Institute, M4N 3M5, Toronto, ON, Canada
| | - Isabelle Aubert
- Biological Sciences, Sunnybrook Research Institute, M4N 3M5, Toronto, ON, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, M5S 1A8, Toronto, ON, Canada
| | - JoAnne McLaurin
- Biological Sciences, Sunnybrook Research Institute, M4N 3M5, Toronto, ON, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, M5S 1A8, Toronto, ON, Canada
| |
Collapse
|
224
|
Casamenti F, Stefani M. Olive polyphenols: new promising agents to combat aging-associated neurodegeneration. Expert Rev Neurother 2016; 17:345-358. [DOI: 10.1080/14737175.2017.1245617] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Fiorella Casamenti
- Department of Neuroscience, Psychology, Division of Pharmacology and Toxicology, Drug Research and Child Health, University of Florence, Florence, Italy
| | - Massimo Stefani
- Department of Biomedical Experimental and Clinical Sciences ‘Mario Serio’, University of Florence, Florence, Italy
| |
Collapse
|
225
|
Rigacci S, Miceli C, Nediani C, Berti A, Cascella R, Pantano D, Nardiello P, Luccarini I, Casamenti F, Stefani M. Oleuropein aglycone induces autophagy via the AMPK/mTOR signalling pathway: a mechanistic insight. Oncotarget 2016; 6:35344-57. [PMID: 26474288 PMCID: PMC4742109 DOI: 10.18632/oncotarget.6119] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 09/12/2015] [Indexed: 01/21/2023] Open
Abstract
The healthy effects of plant polyphenols, some of which characterize the so-called Mediterranean diet, have been shown to arise from epigenetic and biological modifications resulting, among others, in autophagy stimulation. Our previous work highlighted the beneficial effects of oleuropein aglycone (OLE), the main polyphenol found in the extra virgin olive oil, against neurodegeneration both in cultured cells and in model organisms, focusing, in particular, autophagy activation. In this study we investigated more in depth the molecular and cellular mechanisms of autophagy induction by OLE using cultured neuroblastoma cells and an OLE-fed mouse model of amylod beta (Aβ) deposition. We found that OLE triggers autophagy in cultured cells through the Ca2+-CAMKKβ-AMPK axis. In particular, in these cells OLE induces a rapid release of Ca2+ from the SR stores which, in turn, activates CAMKKβ, with subsequent phosphorylation and activation of AMPK. The link between AMPK activation and mTOR inhibition was shown in the OLE-fed animal model in which we found that decreased phospho-mTOR immunoreactivity and phosphorylated mTOR substrate p70 S6K levels match enhanced phospho-AMPK levels, supporting the idea that autophagy activation by OLE proceeds through mTOR inhibition. Our results agree with those reported for other plant polyphenols, suggesting a shared molecular mechanism underlying the healthy effects of these substances against ageing, neurodegeneration, cancer, diabetes and other diseases implying autophagy dysfunction.
Collapse
Affiliation(s)
- Stefania Rigacci
- Department of Experimental and Clinical Biomedical Sciences, Division of Pharmacology and Toxicology, University of Florence, Florence, Italy
| | - Caterina Miceli
- Department of Experimental and Clinical Biomedical Sciences, Division of Pharmacology and Toxicology, University of Florence, Florence, Italy
| | - Chiara Nediani
- Department of Experimental and Clinical Biomedical Sciences, Division of Pharmacology and Toxicology, University of Florence, Florence, Italy
| | - Andrea Berti
- Department of Experimental and Clinical Biomedical Sciences, Division of Pharmacology and Toxicology, University of Florence, Florence, Italy
| | - Roberta Cascella
- Department of Experimental and Clinical Biomedical Sciences, Division of Pharmacology and Toxicology, University of Florence, Florence, Italy
| | - Daniela Pantano
- Department of Neuroscience, Psychology, Drug Research and Child Health, Division of Pharmacology and Toxicology, University of Florence, Florence, Italy
| | - Pamela Nardiello
- Department of Neuroscience, Psychology, Drug Research and Child Health, Division of Pharmacology and Toxicology, University of Florence, Florence, Italy
| | - Ilaria Luccarini
- Department of Neuroscience, Psychology, Drug Research and Child Health, Division of Pharmacology and Toxicology, University of Florence, Florence, Italy
| | - Fiorella Casamenti
- Department of Neuroscience, Psychology, Drug Research and Child Health, Division of Pharmacology and Toxicology, University of Florence, Florence, Italy
| | - Massimo Stefani
- Department of Experimental and Clinical Biomedical Sciences, Division of Pharmacology and Toxicology, University of Florence, Florence, Italy
| |
Collapse
|
226
|
Translational Assays for Assessment of Cognition in Rodent Models of Alzheimer’s Disease and Dementia. J Mol Neurosci 2016; 60:371-382. [DOI: 10.1007/s12031-016-0837-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Accepted: 08/31/2016] [Indexed: 02/06/2023]
|
227
|
Expression of Phenotypic Astrocyte Marker Is Increased in a Transgenic Mouse Model of Alzheimer's Disease versus Age-Matched Controls: A Presymptomatic Stage Study. Int J Alzheimers Dis 2016; 2016:5696241. [PMID: 27672476 PMCID: PMC5031839 DOI: 10.1155/2016/5696241] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Revised: 08/03/2016] [Accepted: 08/14/2016] [Indexed: 12/29/2022] Open
Abstract
Recent mouse studies of the presymptomatic stage of Alzheimer's disease (AD) have suggested that proinflammatory changes, such as glial activation and cytokine induction, may occur already at this early stage through unknown mechanisms. Because TNFα contributes to increased Aβ production from the Aβ precursor protein (APP), we assessed a putative correlation between APP/Aβ and TNFα during the presymptomatic stage as well as early astrocyte activation in the hippocampus of 3-month-old APPswe/PS1dE9 mice. While Western blots revealed significant APP expression, Aβ was not detectable by Western blot or ELISA attesting that 3-month-old, APPswe/PS1dE9 mice are at a presymptomatic stage of AD-like pathology. Western blots were also used to show increased GFAP expression in transgenic mice that positively correlated with both TNFα and APP, which were also mutually correlated. Subregional immunohistochemical quantification of phenotypic (GFAP) and functional (TSPO) markers of astrocyte activation indicated a selective and significant increase in GFAP-immunoreactive (IR) cells in the dentate gyrus of APPswe/PS1dE9 mice. Our data suggest that subtle morphological and phenotypic alterations, compatible with the engagement of astrocyte along the activation pathway, occur in the hippocampus already at the presymptomatic stage of AD.
Collapse
|
228
|
Substituted 4-morpholine N-arylsulfonamides as γ-secretase inhibitors. Eur J Med Chem 2016; 124:36-48. [PMID: 27560281 DOI: 10.1016/j.ejmech.2016.08.024] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Revised: 08/11/2016] [Accepted: 08/12/2016] [Indexed: 11/23/2022]
Abstract
The design, synthesis, SAR, and biological profile of a substituted 4-morpholine sulfonamide series of γ-secretase inhibitors (GSIs) were described. In several cases, the resulting series of GSIs reduced CYP liabilities and improved γ-secretase inhibition activity compared to our previous research series. Selected compounds demonstrated significant reduction of amyloid-β (Aβ) after acute oral dosing in a transgenic animal model of Alzheimer's disease (AD).
Collapse
|
229
|
Cavanagh C, Tse YC, Nguyen HB, Krantic S, Breitner JCS, Quirion R, Wong TP. Inhibiting tumor necrosis factor-α before amyloidosis prevents synaptic deficits in an Alzheimer's disease model. Neurobiol Aging 2016; 47:41-49. [PMID: 27552480 DOI: 10.1016/j.neurobiolaging.2016.07.009] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Revised: 07/11/2016] [Accepted: 07/15/2016] [Indexed: 12/12/2022]
Abstract
Deficits in synaptic structure and function are likely to underlie cognitive impairments in Alzheimer's disease. While synaptic deficits are commonly found in animal models of amyloidosis, it is unclear how amyloid pathology may impair synaptic functions. In some amyloid mouse models of Alzheimer's disease, however, synaptic deficits are preceded by hyperexcitability of glutamate synapses. In the amyloid transgenic mouse model TgCRND8, we therefore investigated whether early enhancement of glutamatergic transmission was responsible for development of later synaptic deficits. Hippocampi from 1-month-old TgCRND8 mice revealed increased basal transmission and plasticity of glutamate synapses that was related to increased levels of tumor necrosis factor α (TNFα). Treating these 1-month-old mice for 4 weeks with the TNFα inhibitor XPro1595 prevented synaptic deficits otherwise apparent at the age of 6 months. In this mouse model at least, reversing the hyperexcitability of glutamate synapses via TNFα blockade before the onset of amyloid plaque formation prevented later synaptic deficits.
Collapse
Affiliation(s)
- Chelsea Cavanagh
- Douglas Mental Health University Institute, Montreal, Quebec, Canada; Integrated Program in Neuroscience, McGill University, Montreal, Quebec, Canada
| | - Yiu Chung Tse
- Douglas Mental Health University Institute, Montreal, Quebec, Canada
| | - Huy-Binh Nguyen
- Douglas Mental Health University Institute, Montreal, Quebec, Canada; Integrated Program in Neuroscience, McGill University, Montreal, Quebec, Canada
| | - Slavica Krantic
- Sorbonne Universités, UPMC Univ Paris 06, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France; INSERM, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France; Centre National de la Recherche Scientifique (ou CNRS) ERL 8228, Centre de Recherche des Cordeliers, Paris, France
| | - John C S Breitner
- Douglas Mental Health University Institute, Montreal, Quebec, Canada; Centre for Studies on Prevention of Alzheimer's Disease, Montreal, Quebec, Canada; Department of Psychiatry, McGill University, Montreal, Quebec, Canada
| | - Remi Quirion
- Douglas Mental Health University Institute, Montreal, Quebec, Canada; Integrated Program in Neuroscience, McGill University, Montreal, Quebec, Canada; Department of Psychiatry, McGill University, Montreal, Quebec, Canada
| | - Tak Pan Wong
- Douglas Mental Health University Institute, Montreal, Quebec, Canada; Integrated Program in Neuroscience, McGill University, Montreal, Quebec, Canada; Department of Psychiatry, McGill University, Montreal, Quebec, Canada.
| |
Collapse
|
230
|
Chung YC, Kruyer A, Yao Y, Feierman E, Richards A, Strickland S, Norris EH. Hyperhomocysteinemia exacerbates Alzheimer's disease pathology by way of the β-amyloid fibrinogen interaction. J Thromb Haemost 2016; 14:1442-52. [PMID: 27090576 PMCID: PMC4949110 DOI: 10.1111/jth.13340] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 03/31/2016] [Indexed: 01/02/2023]
Abstract
UNLABELLED Essentials Evidence suggests a comorbidity between hyperhomocysteinemia (HHC) and Alzheimer's disease (AD). Homocysteine (HC) could affect the β-amyloid (Aβ)-fibrinogen interaction in AD pathology. AD patients with concomitant HHC have increased fibrin and Aβ deposits in their brains. HC contributes to AD pathology via the Aβ-fibrinogen interaction. SUMMARY Background Accumulating clinical evidence suggests that hyperhomocysteinemia (HHC) is correlated with Alzheimer's disease (AD) and vascular dementia. Objective This study was carried out to elucidate the specific role of elevated homocysteine (HC) levels in AD pathophysiology. Methods Immunohistochemistry was used to examine β-amyloid (Aβ) deposition along blood vessels, also known as cerebral amyloid angiopathy (CAA), fibrin(ogen) deposition, and their correlation to each other in the brains of AD patients with and without HHC. To study AD-HHC co-morbidity in detail, an AD mouse model was administered a high methionine diet for several months. Parenchymal Aβ plaques, CAA-positive vessels and fibrin deposits were then assessed by immunohistochemistry at different stages of AD progression. Memory deficits were evaluated with contextual fear conditioning and the Barnes maze. Additionally, the effect of HC and its metabolite, homocysteine thiolactone (HCTL), on the Aβ-fibrinogen interaction was analyzed by pull-down, ELISA and fibrin clot formation and fibrinolysis assays in vitro. Results We found increased fibrin(ogen) levels and Aβ deposits in the blood vessels and brain parenchyma of AD patients with HHC. We demonstrate that HC and HCTL enhance the interaction between fibrinogen and Aβ, promote the formation of tighter fibrin clots and delay clot fibrinolysis. Additionally, we show that diet-induced HHC in an AD mouse model leads to severe CAA and parenchymal Aβ deposition, as well as significant impairments in learning and memory. Conclusions These findings suggest that elevated levels of plasma HC/HCTL contribute to AD pathology via the Aβ-fibrin(ogen) interaction.
Collapse
Affiliation(s)
- Young Cheul Chung
- Patricia and John Rosenwald Laboratory of Neurobiology & Genetics, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Anna Kruyer
- Patricia and John Rosenwald Laboratory of Neurobiology & Genetics, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Yao Yao
- Patricia and John Rosenwald Laboratory of Neurobiology & Genetics, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Emily Feierman
- Patricia and John Rosenwald Laboratory of Neurobiology & Genetics, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Allison Richards
- Patricia and John Rosenwald Laboratory of Neurobiology & Genetics, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Sidney Strickland
- Patricia and John Rosenwald Laboratory of Neurobiology & Genetics, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | - Erin H. Norris
- Patricia and John Rosenwald Laboratory of Neurobiology & Genetics, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| |
Collapse
|
231
|
Herring A, Münster Y, Akkaya T, Moghaddam S, Deinsberger K, Meyer J, Zahel J, Sanchez-Mendoza E, Wang Y, Hermann DM, Arzberger T, Teuber-Hanselmann S, Keyvani K. Kallikrein-8 inhibition attenuates Alzheimer's disease pathology in mice. Alzheimers Dement 2016; 12:1273-1287. [PMID: 27327541 DOI: 10.1016/j.jalz.2016.05.006] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Revised: 05/04/2016] [Accepted: 05/22/2016] [Indexed: 10/21/2022]
Abstract
INTRODUCTION Memory loss and increased anxiety are clinical hallmarks of Alzheimer's disease (AD). Kallikrein-8 is a protease implicated in memory acquisition and anxiety, and its mRNA is known to be up-regulated in AD-affected human hippocampus. Therefore, an involvement of Kallikrein-8 in Alzheimer's pathogenesis is conceivable but remains to be proved. METHODS We determined the cerebral expression of Kallikrein-8 mRNA and protein during the course of AD in patients and in transgenic mice and tested the impact of Kallikrein-8 inhibition on AD-related pathology in mice and in primary glial cells. RESULTS Kallikrein-8 mRNA and protein were up-regulated in both species at incipient stages of AD. Kallikrein-8 inhibition impeded amyloidogenic amyloid-precursor-protein processing, facilitated amyloid β (Aβ) clearance across the blood-brain-barrier, boosted autophagy, reduced Aβ load and tau pathology, enhanced neuroplasticity, reversed molecular signatures of anxiety, and ultimately improved memory and reduced fear. DISCUSSION Kallikrein-8 is a promising new therapeutic target against AD.
Collapse
Affiliation(s)
- Arne Herring
- Institute of Neuropathology, University of Duisburg-Essen, Essen, Germany.
| | - Yvonne Münster
- Institute of Neuropathology, University of Duisburg-Essen, Essen, Germany
| | - Tamer Akkaya
- Institute of Neuropathology, University of Duisburg-Essen, Essen, Germany
| | - Sahar Moghaddam
- Institute of Neuropathology, University of Duisburg-Essen, Essen, Germany
| | | | - Jakob Meyer
- Institute of Neuropathology, University of Duisburg-Essen, Essen, Germany
| | - Julia Zahel
- Institute of Neuropathology, University of Duisburg-Essen, Essen, Germany
| | | | - Yachao Wang
- Department of Neurology, University of Duisburg-Essen, Essen, Germany
| | - Dirk M Hermann
- Department of Neurology, University of Duisburg-Essen, Essen, Germany
| | - Thomas Arzberger
- Department of Psychiatry and Psychotherapy, Ludwig-Maximilians-University Munich, Munich, Germany; Center for Neuropathology and Prion Research, Ludwig-Maximilians-University Munich, Munich, Germany
| | | | - Kathy Keyvani
- Institute of Neuropathology, University of Duisburg-Essen, Essen, Germany.
| |
Collapse
|
232
|
Herring A, Münster Y, Metzdorf J, Bolczek B, Krüssel S, Krieter D, Yavuz I, Karim F, Roggendorf C, Stang A, Wang Y, Hermann DM, Teuber-Hanselmann S, Keyvani K. Late running is not too late against Alzheimer's pathology. Neurobiol Dis 2016; 94:44-54. [PMID: 27312772 DOI: 10.1016/j.nbd.2016.06.003] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Revised: 05/27/2016] [Accepted: 06/11/2016] [Indexed: 11/16/2022] Open
Abstract
In the last decade a vast number of animal studies have produced overwhelming evidence that exercise not only compensates for memory loss by increasing brain plasticity and cognitive reserve but also directly counteracts Alzheimer-like pathology when provided before disease onset or in early disease stages. But so far, there is little knowledge about therapeutic effects of training when started in advanced disease stages. In the present study we show that following seven months of sedentary life style five months of wheel running, started four months after disease onset was still able to mitigate at least some aspects of the full-blown Alzheimer's pathology in TgCRND8 mice. Late running had mild but significant effects on structural plasticity by increasing the dendritic complexity. It further reduced beta-amyloid (Aβ) plaque burden and enhanced Aβ clearance across the blood-brain barrier, along with attenuating microgliosis, inflammation, oxidative stress, and autophagy deficits, resulting in better memory performance and less agitation. However, unlike early exercise, late running did not affect abnormal amyloid precursor protein metabolism, tau pathology, or angiogenesis. These results allow concluding that it is never too late to counteract Alzheimer's disease with physical training but the earlier the intervention starts, the more pronounced is the therapeutic potential.
Collapse
Affiliation(s)
- Arne Herring
- Institute of Neuropathology, University of Duisburg-Essen, Hufelandstr. 55, 45122 Essen, Germany
| | - Yvonne Münster
- Institute of Neuropathology, University of Duisburg-Essen, Hufelandstr. 55, 45122 Essen, Germany
| | - Judith Metzdorf
- Institute of Neuropathology, University of Duisburg-Essen, Hufelandstr. 55, 45122 Essen, Germany
| | - Bastien Bolczek
- Institute of Neuropathology, University of Duisburg-Essen, Hufelandstr. 55, 45122 Essen, Germany
| | - Sarah Krüssel
- Institute of Neuropathology, University of Duisburg-Essen, Hufelandstr. 55, 45122 Essen, Germany
| | - David Krieter
- Institute of Neuropathology, University of Duisburg-Essen, Hufelandstr. 55, 45122 Essen, Germany
| | - Ilkay Yavuz
- Institute of Neuropathology, University of Duisburg-Essen, Hufelandstr. 55, 45122 Essen, Germany
| | - Fro Karim
- Institute of Neuropathology, University of Duisburg-Essen, Hufelandstr. 55, 45122 Essen, Germany
| | - Constanze Roggendorf
- Institute of Neuropathology, University of Duisburg-Essen, Hufelandstr. 55, 45122 Essen, Germany
| | - Anthony Stang
- Institute of Neuropathology, University of Duisburg-Essen, Hufelandstr. 55, 45122 Essen, Germany
| | - Yachao Wang
- Department of Neurology, University of Duisburg-Essen, Hufelandstr. 55, 45122 Essen, Germany
| | - Dirk M Hermann
- Department of Neurology, University of Duisburg-Essen, Hufelandstr. 55, 45122 Essen, Germany
| | - Sarah Teuber-Hanselmann
- Institute of Neuropathology, University of Duisburg-Essen, Hufelandstr. 55, 45122 Essen, Germany
| | - Kathy Keyvani
- Institute of Neuropathology, University of Duisburg-Essen, Hufelandstr. 55, 45122 Essen, Germany.
| |
Collapse
|
233
|
Harwell CS, Coleman MP. Synaptophysin depletion and intraneuronal Aβ in organotypic hippocampal slice cultures from huAPP transgenic mice. Mol Neurodegener 2016; 11:44. [PMID: 27287430 PMCID: PMC4903008 DOI: 10.1186/s13024-016-0110-7] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Accepted: 06/01/2016] [Indexed: 11/10/2022] Open
Abstract
Background To date, there are no effective disease-modifying treatments for Alzheimer’s disease (AD). In order to develop new therapeutics for stages where they are most likely to be effective, it is important to identify the first pathological alterations in the disease cascade. Changes in Aβ concentration have long been reported as one of the first steps, but understanding the source, and earliest consequences, of pathology requires a model system that represents all major CNS cell types, is amenable to repeated observation and sampling, and can be readily manipulated. In this regard, long term organotypic hippocampal slice cultures (OHSCs) from neonatal amyloid mice offer an excellent compromise between in vivo and primary culture studies, largely retaining the cellular composition and neuronal architecture of the in vivo hippocampus, but with the in vitro advantages of accessibility to live imaging, sampling and intervention. Results Here, we report the development and characterisation of progressive pathological changes in an organotypic model from TgCRND8 mice. Aβ1-40 and Aβ1-42 rise progressively in transgenic slice culture medium and stabilise when regular feeding balances continued production. In contrast, intraneuronal Aβ continues to accumulate in close correlation with a specific decline in presynaptic proteins and puncta. Plaque pathology is not evident even when Aβ1-42 is increased by pharmacological manipulation (using calpain inhibitor 1), indicating that soluble Aβ species, or other APP processing products, are sufficient to cause the initial synaptic changes. Conclusions Organotypic brain slices from TgCRND8 mice represent an important new system for understanding mechanisms of Aβ generation, release and progressive toxicity. The pathology observed in these cultures will allow for rapid assessment of disease modifying compounds in a system amenable to manipulation and observation. Electronic supplementary material The online version of this article (doi:10.1186/s13024-016-0110-7) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Claire S Harwell
- The Babraham Institute, Babraham Research Campus, Cambridge, CB22 3AT, UK
| | - Michael P Coleman
- The Babraham Institute, Babraham Research Campus, Cambridge, CB22 3AT, UK. .,Present Address: John van Geest Centre for Brain Repair, Forvie Site, Robinson Way, Cambridge, CB2 0PY, UK.
| |
Collapse
|
234
|
Reichel JM, Bedenk BT, Gassen NC, Hafner K, Bura SA, Almeida-Correa S, Genewsky A, Dedic N, Giesert F, Agarwal A, Nave KA, Rein T, Czisch M, Deussing JM, Wotjak CT. Beware of your Cre-Ation: lacZ expression impairs neuronal integrity and hippocampus-dependent memory. Hippocampus 2016; 26:1250-64. [PMID: 27101945 DOI: 10.1002/hipo.22601] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/08/2016] [Indexed: 12/28/2022]
Abstract
Expression of the lacZ-sequence is a widely used reporter-tool to assess the transgenic and/or transfection efficacy of a target gene in mice. Once activated, lacZ is permanently expressed. However, protein accumulation is one of the hallmarks of neurodegenerative diseases. Furthermore, the protein product of the bacterial lacZ gene is ß-galactosidase, an analog to the mammalian senescence-associated ß-galactosidase, a molecular marker for aging. Therefore we studied the behavioral, structural and molecular consequences of lacZ expression in distinct neuronal sub-populations. lacZ expression in cortical glutamatergic neurons resulted in severe impairments in hippocampus-dependent memory accompanied by marked structural alterations throughout the CNS. In contrast, GFP expression or the expression of the ChR2/YFP fusion product in the same cell populations did not result in either cognitive or structural deficits. GABAergic lacZ expression caused significantly decreased hyper-arousal and mild cognitive deficits. Attenuated structural and behavioral consequences of lacZ expression could also be induced in adulthood, and lacZ transfection in neuronal cell cultures significantly decreased their viability. Our findings provide a strong caveat against the use of lacZ reporter mice for phenotyping studies and point to a particular sensitivity of the hippocampus formation to detrimental consequences of lacZ expression. © 2016 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- J M Reichel
- Department of Stress Neurobiology and Neurogenetics, Max Planck Institute of Psychiatry, 80804, Munich, Germany.,Department of Molecular Pharmacology, Albert Einstein College of Medicine, 10461, Bronx, New York
| | - B T Bedenk
- Department of Stress Neurobiology and Neurogenetics, Max Planck Institute of Psychiatry, 80804, Munich, Germany.,Core Unit Neuroimaging, Max Planck Institute of Psychiatry, 80804, Munich, Germany
| | - N C Gassen
- Department of Translational Research in Psychiatry, Max Planck Institute of Psychiatry, 80804, Munich, Germany
| | - K Hafner
- Department of Translational Research in Psychiatry, Max Planck Institute of Psychiatry, 80804, Munich, Germany
| | - S A Bura
- Department of Stress Neurobiology and Neurogenetics, Max Planck Institute of Psychiatry, 80804, Munich, Germany
| | - S Almeida-Correa
- Department of Stress Neurobiology and Neurogenetics, Max Planck Institute of Psychiatry, 80804, Munich, Germany
| | - A Genewsky
- Department of Stress Neurobiology and Neurogenetics, Max Planck Institute of Psychiatry, 80804, Munich, Germany
| | - N Dedic
- Department of Stress Neurobiology and Neurogenetics, Max Planck Institute of Psychiatry, 80804, Munich, Germany
| | - F Giesert
- Institute of Developmental Genetics, Helmholtz Zentrum Muenchen, German Research Center for Environmental Health (GmbH), Ingolstaedter Landstrasse 1, Neuherberg, D-85764, Germany
| | - A Agarwal
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University, Baltimore, Maryland
| | - K-A Nave
- Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Goettingen, 37075, Germany
| | - T Rein
- Department of Translational Research in Psychiatry, Max Planck Institute of Psychiatry, 80804, Munich, Germany
| | - M Czisch
- Department of Stress Neurobiology and Neurogenetics, Max Planck Institute of Psychiatry, 80804, Munich, Germany.,Core Unit Neuroimaging, Max Planck Institute of Psychiatry, 80804, Munich, Germany
| | - J M Deussing
- Department of Stress Neurobiology and Neurogenetics, Max Planck Institute of Psychiatry, 80804, Munich, Germany
| | - C T Wotjak
- Department of Stress Neurobiology and Neurogenetics, Max Planck Institute of Psychiatry, 80804, Munich, Germany.
| |
Collapse
|
235
|
Pantano D, Luccarini I, Nardiello P, Servili M, Stefani M, Casamenti F. Oleuropein aglycone and polyphenols from olive mill waste water ameliorate cognitive deficits and neuropathology. Br J Clin Pharmacol 2016; 83:54-62. [PMID: 27131215 DOI: 10.1111/bcp.12993] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Revised: 04/11/2016] [Accepted: 04/28/2016] [Indexed: 01/01/2023] Open
Abstract
AIM In TgCRND8 (Tg) mice we checked the dose-response effect of diet supplementation with oleuropein aglycone (OLE) at 12.5 or 0.5 mg kg-1 of diet. We also studied the effects of dietary intake of the mix of polyphenols present in olive mill waste water administered at a total dose as high as the highest dose of OLE (50 mg kg-1 of diet) previously investigated. METHODS Four month-old Tg mice were equally divided into four groups and treated for 8 weeks with a modified low fat (5.0%) AIN-76 A diet (10 g day-1 per mouse) as such, supplemented with OLE (12.5 or 0.5 mg kg-1 of diet) or with a mix of polyphenols (50 mg kg-1 of diet) found in olive mill waste water. Behavioural performance was evaluated by the step down inhibitory avoidance and object recognition tests. Neuropathology was analyzed by immunohistochemistry. RESULTS OLE supplementation at 12.5 mg kg-1 of diet and the mix of polyphenols was found to improve significantly cognitive functions of Tg mice (P < 0.0001). Aß42 and pE-3Aß plaque area and number were significantly reduced in the cortex by OLE and in the cortex and hippocampus by the mix of polyphenols (P < 0.01, P < 0.001 and P < 0.0001). Similar autophagy induction was found in the brain cortex of differently treated mice. CONCLUSION Our results extend previous data showing that the effects of OLE on behavioural performance and neuropathology are dose-dependent and not closely related to OLE by itself. In fact, diet supplementation with the same dose of a mix of polyphenols found in olive mill waste water resulted in comparable neuroprotection.
Collapse
Affiliation(s)
- Daniela Pantano
- Department of Neuroscience, Psychology, Drug Research and Child Health, Division of Pharmacology and Toxicology, University of Florence, Viale G. Pieraccini, 6, 50139, Florence
| | - Ilaria Luccarini
- Department of Neuroscience, Psychology, Drug Research and Child Health, Division of Pharmacology and Toxicology, University of Florence, Viale G. Pieraccini, 6, 50139, Florence
| | - Pamela Nardiello
- Department of Neuroscience, Psychology, Drug Research and Child Health, Division of Pharmacology and Toxicology, University of Florence, Viale G. Pieraccini, 6, 50139, Florence
| | - Maurizio Servili
- Department of Agricultural Sciences, Food and Environment, University of Perugia, Via S. Costanzo, 06126, Perugia, Italy
| | - Massimo Stefani
- Department of Experimental and Clinical Biomedical Sciences, University of Florence, Viale G. B. Morgagni, 50, 50134, Florence
| | - Fiorella Casamenti
- Department of Neuroscience, Psychology, Drug Research and Child Health, Division of Pharmacology and Toxicology, University of Florence, Viale G. Pieraccini, 6, 50139, Florence
| |
Collapse
|
236
|
Schubert KO, Weiland F, Baune BT, Hoffmann P. The use of MALDI-MSI in the investigation of psychiatric and neurodegenerative disorders: A review. Proteomics 2016; 16:1747-58. [DOI: 10.1002/pmic.201500460] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Revised: 02/08/2016] [Accepted: 02/24/2016] [Indexed: 11/11/2022]
Affiliation(s)
| | - Florian Weiland
- Adelaide Proteomics Centre; The University of Adelaide; Adelaide Australia
- Institute for Photonics and Advanced Sensing (IPAS); The University of Adelaide; Adelaide Australia
| | - Bernhard T. Baune
- Discipline of Psychiatry; The University of Adelaide; Adelaide Australia
| | - Peter Hoffmann
- Adelaide Proteomics Centre; The University of Adelaide; Adelaide Australia
- Institute for Photonics and Advanced Sensing (IPAS); The University of Adelaide; Adelaide Australia
| |
Collapse
|
237
|
Abstract
Large conductance Ca(2+)- and voltage-activated K(+) (BK) channels are widely distributed in the postnatal central nervous system (CNS). BK channels play a pleiotropic role in regulating the activity of brain and spinal cord neural circuits by providing a negative feedback mechanism for local increases in intracellular Ca(2+) concentrations. In neurons, they regulate the timing and duration of K(+) influx such that they can either increase or decrease firing depending on the cellular context, and they can suppress neurotransmitter release from presynaptic terminals. In addition, BK channels located in astrocytes and arterial myocytes modulate cerebral blood flow. Not surprisingly, both loss and gain of BK channel function have been associated with CNS disorders such as epilepsy, ataxia, mental retardation, and chronic pain. On the other hand, the neuroprotective role played by BK channels in a number of pathological situations could potentially be leveraged to correct neurological dysfunction.
Collapse
|
238
|
Ryan SM, Kelly ÁM. Exercise as a pro-cognitive, pro-neurogenic and anti-inflammatory intervention in transgenic mouse models of Alzheimer's disease. Ageing Res Rev 2016; 27:77-92. [PMID: 27039886 DOI: 10.1016/j.arr.2016.03.007] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 03/22/2016] [Accepted: 03/30/2016] [Indexed: 12/20/2022]
Abstract
It is now well established, at least in animal models, that exercise elicits potent pro-cognitive and pro-neurogenic effects. Alzheimer's disease (AD) is one of the leading causes of dementia and represents one of the greatest burdens on healthcare systems worldwide, with no effective treatment for the disease to date. Exercise presents a promising non-pharmacological option to potentially delay the onset of or slow down the progression of AD. Exercise interventions in mouse models of AD have been explored and have been found to reduce amyloid pathology and improve cognitive function. More recent studies have expanded the research question by investigating potential pro-neurogenic and anti-inflammatory effects of exercise. In this review we summarise studies that have examined exercise-mediated effects on AD pathology, cognitive function, hippocampal neurogenesis and neuroinflammation in transgenic mouse models of AD. Furthermore, we attempt to identify the optimum exercise conditions required to elicit the greatest benefits, taking into account age and pathology of the model, as well as type and duration of exercise.
Collapse
|
239
|
Hazra A, Corbett BF, You JC, Aschmies S, Zhao L, Li K, Lepore AC, Marsh ED, Chin J. Corticothalamic network dysfunction and behavioral deficits in a mouse model of Alzheimer's disease. Neurobiol Aging 2016; 44:96-107. [PMID: 27318137 DOI: 10.1016/j.neurobiolaging.2016.04.016] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 04/21/2016] [Accepted: 04/22/2016] [Indexed: 10/21/2022]
Abstract
Alzheimer's disease is associated with cognitive decline and seizures. Growing evidence indicates that seizures contribute to cognitive deficits early in disease, but how they develop and impact cognition are unclear. To investigate potential mechanisms, we studied a mouse model that overexpresses mutant human amyloid precursor protein with high levels of amyloid beta (Aβ). These mice develop generalized epileptiform activity, including nonconvulsive seizures, consistent with alterations in corticothalamic network activity. Amyloid precursor protein mice exhibited reduced activity marker expression in the reticular thalamic nucleus, a key inhibitory regulatory nucleus, and increased activity marker expression in downstream thalamic relay targets that project to cortex and limbic structures. Slice recordings revealed impaired cortical inputs to the reticular thalamic nucleus that may contribute to corticothalamic dysfunction. These results are consistent with our findings of impaired sleep maintenance in amyloid precursor protein mice. Finally, the severity of sleep impairments predicted the severity of deficits in Morris water maze, suggesting corticothalamic dysfunction may relate to hippocampal dysfunction, and may be a pathophysiological mechanism underlying multiple behavioral and cognitive alterations in Alzheimer's disease.
Collapse
Affiliation(s)
- Anupam Hazra
- Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA 19107.,Farber Institute for Neurosciences, Thomas Jefferson University, Philadelphia, PA 19107
| | - Brian F Corbett
- Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA 19107.,Farber Institute for Neurosciences, Thomas Jefferson University, Philadelphia, PA 19107
| | - Jason C You
- Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA 19107.,Farber Institute for Neurosciences, Thomas Jefferson University, Philadelphia, PA 19107
| | - Suzan Aschmies
- Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA 19107.,Farber Institute for Neurosciences, Thomas Jefferson University, Philadelphia, PA 19107
| | - Lijuan Zhao
- Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA 19107.,Farber Institute for Neurosciences, Thomas Jefferson University, Philadelphia, PA 19107
| | - Ke Li
- Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA 19107.,Farber Institute for Neurosciences, Thomas Jefferson University, Philadelphia, PA 19107
| | - Angelo C Lepore
- Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA 19107.,Farber Institute for Neurosciences, Thomas Jefferson University, Philadelphia, PA 19107
| | - Eric D Marsh
- Departments of Pediatrics and Neurology, Children's Hospital of Philadelphia and the Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104
| | - Jeannie Chin
- Department of Neuroscience, Thomas Jefferson University, Philadelphia, PA 19107.,Farber Institute for Neurosciences, Thomas Jefferson University, Philadelphia, PA 19107.,Memory & Brain Research Center, Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030
| |
Collapse
|
240
|
Bouvier DS, Jones EV, Quesseveur G, Davoli MA, A Ferreira T, Quirion R, Mechawar N, Murai KK. High Resolution Dissection of Reactive Glial Nets in Alzheimer's Disease. Sci Rep 2016; 6:24544. [PMID: 27090093 PMCID: PMC4835751 DOI: 10.1038/srep24544] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 03/31/2016] [Indexed: 12/13/2022] Open
Abstract
Fixed human brain samples in tissue repositories hold great potential for unlocking complexities of the brain and its alteration with disease. However, current methodology for simultaneously resolving complex three-dimensional (3D) cellular anatomy and organization, as well as, intricate details of human brain cells in tissue has been limited due to weak labeling characteristics of the tissue and high background levels. To expose the potential of these samples, we developed a method to overcome these major limitations. This approach offers an unprecedented view of cytoarchitecture and subcellular detail of human brain cells, from cellular networks to individual synapses. Applying the method to AD samples, we expose complex features of microglial cells and astrocytes in the disease. Through this methodology, we show that these cells form specialized 3D structures in AD that we refer to as reactive glial nets (RGNs). RGNs are areas of concentrated neuronal injury, inflammation, and tauopathy and display unique features around β-amyloid plaque types. RGNs have conserved properties in an AD mouse model and display a developmental pattern coinciding with the progressive accumulation of neuropathology. The method provided here will help reveal novel features of the healthy and diseased human brain, and aid experimental design in translational brain research.
Collapse
Affiliation(s)
- David S Bouvier
- Centre for Research in Neuroscience, Department of Neurology and Neurosurgery, The Research Institute of the McGill University Health Centre, Montreal General Hospital, Montreal, Quebec, Canada
| | - Emma V Jones
- Centre for Research in Neuroscience, Department of Neurology and Neurosurgery, The Research Institute of the McGill University Health Centre, Montreal General Hospital, Montreal, Quebec, Canada
| | - Gaël Quesseveur
- Centre for Research in Neuroscience, Department of Neurology and Neurosurgery, The Research Institute of the McGill University Health Centre, Montreal General Hospital, Montreal, Quebec, Canada
| | - Maria Antonietta Davoli
- Douglas Mental Health University Institute, Department of Psychiatry, McGill Group for Suicide Studies, McGill University, Montreal, Quebec, Canada
| | - Tiago A Ferreira
- Centre for Research in Neuroscience, Department of Neurology and Neurosurgery, The Research Institute of the McGill University Health Centre, Montreal General Hospital, Montreal, Quebec, Canada
| | - Rémi Quirion
- Douglas Mental Health University Institute, Department of Psychiatry, McGill Group for Suicide Studies, McGill University, Montreal, Quebec, Canada
| | - Naguib Mechawar
- Douglas Mental Health University Institute, Department of Psychiatry, McGill Group for Suicide Studies, McGill University, Montreal, Quebec, Canada
| | - Keith K Murai
- Centre for Research in Neuroscience, Department of Neurology and Neurosurgery, The Research Institute of the McGill University Health Centre, Montreal General Hospital, Montreal, Quebec, Canada
| |
Collapse
|
241
|
Granger MW, Franko B, Taylor MW, Messier C, George-Hyslop PS, Bennett SA. A TgCRND8 Mouse Model of Alzheimer’s Disease Exhibits Sexual Dimorphisms in Behavioral Indices of Cognitive Reserve. J Alzheimers Dis 2016; 51:757-73. [DOI: 10.3233/jad-150587] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Matthew W. Granger
- Neural Regeneration Laboratory, Ottawa Institute of Systems Biology, Department of Biochemistry, Microbiology, and Immunology, University of Ottawa, Ottawa, ON, Canada
| | - Bettina Franko
- Neural Regeneration Laboratory, Ottawa Institute of Systems Biology, Department of Biochemistry, Microbiology, and Immunology, University of Ottawa, Ottawa, ON, Canada
| | - Matthew W. Taylor
- Neural Regeneration Laboratory, Ottawa Institute of Systems Biology, Department of Biochemistry, Microbiology, and Immunology, University of Ottawa, Ottawa, ON, Canada
| | - Claude Messier
- School of Psychology, University of Ottawa, Ottawa, ON, Canada
| | - Peter St. George-Hyslop
- Department of Clinical Neurosciences, Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK and Tanz Centre for Research in Neurodegenerative Diseases University of Toronto, Toronto, ON, Canada
| | - Steffany A.L. Bennett
- Neural Regeneration Laboratory, Ottawa Institute of Systems Biology, Department of Biochemistry, Microbiology, and Immunology, University of Ottawa, Ottawa, ON, Canada
| |
Collapse
|
242
|
Synthesis and Preliminary Biological Evaluation of Fluorescent Glycofused Tricyclic Derivatives of Amyloid β-Peptide Ligands. European J Org Chem 2016. [DOI: 10.1002/ejoc.201501593] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
243
|
Tackling amyloidogenesis in Alzheimer's disease with A2V variants of Amyloid-β. Sci Rep 2016; 6:20949. [PMID: 26864599 PMCID: PMC4750079 DOI: 10.1038/srep20949] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 01/13/2016] [Indexed: 02/05/2023] Open
Abstract
We developed a novel therapeutic strategy for Alzheimer’s disease (AD) exploiting the properties of a natural variant of Amyloid-β (Aβ) carrying the A2V substitution, which protects heterozygous carriers from AD by its ability to interact with wild-type Aβ, hindering conformational changes and assembly thereof. As prototypic compound we designed a six-mer mutated peptide (Aβ1-6A2V), linked to the HIV-related TAT protein, which is widely used for brain delivery and cell membrane penetration of drugs. The resulting molecule [Aβ1-6A2VTAT(D)] revealed strong anti-amyloidogenic effects in vitro and protected human neuroblastoma cells from Aβ toxicity. Preclinical studies in AD mouse models showed that short-term treatment with Aβ1-6A2VTAT(D) inhibits Aβ aggregation and cerebral amyloid deposition, but a long treatment schedule unexpectedly increases amyloid burden, although preventing cognitive deterioration. Our data support the view that the AβA2V-based strategy can be successfully used for the development of treatments for AD, as suggested by the natural protection against the disease in human A2V heterozygous carriers. The undesirable outcome of the prolonged treatment with Aβ1-6A2VTAT(D) was likely due to the TAT intrinsic attitude to increase Aβ production, avidly bind amyloid and boost its seeding activity, warning against the use of the TAT carrier in the design of AD therapeutics.
Collapse
|
244
|
Kimura R, MacTavish D, Yang J, Westaway D, Jhamandas JH. Pramlintide Antagonizes Beta Amyloid (Aβ)- and Human Amylin-Induced Depression of Hippocampal Long-Term Potentiation. Mol Neurobiol 2016; 54:748-754. [PMID: 26768593 DOI: 10.1007/s12035-016-9684-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Accepted: 01/05/2016] [Indexed: 02/02/2023]
Abstract
Accumulation of amyloid-β peptide (Aβ) is a pathological hallmark of Alzheimer's disease (AD). We have previously demonstrated that electrophysiological and neurotoxic effects of Aβ and human amylin are expressed via the amylin receptor. Recently, pramlintide, a synthetic analog of amylin, has been reported to improve cognitive function in transgenic AD mouse models. In this study, we examined the effects of pramlintide on Aβ1-42 and human amylin-evoked depression of long-term potentiation (LTP) at Schaeffer collateral-CA1 hippocampal synapses. In mouse hippocampal brain slices, field excitatory postsynaptic potentials (fEPSPs) were recorded from the stratum radiatum layer of the CA1 area in response to electrical stimulation of Schaeffer collateral afferents and LTP induced by 3-theta-burst stimulation (TBS) protocol. Aβ1-42 (50 nM) and human amylin (50 nM), but not Aβ42-1 (50 nM), depressed LTP. Pre-application of pramlintide (250 nM) blocked Aβ- and human amylin-induced reduction of LTP without affecting baseline transmission or LTP. We also examined the effects of pramlintide on LTP in transgenic mice (TgCRND8) that over-express amyloid precursor protein. In contrast to wild-type controls, where robust LTP was observed, 10- to 12-month-old TgCRND8 mice show blunted LTP. In TgCRND8 mice, basal LTP is enhanced by application of pramlintide. Our data indicate that pramlintide acts as a functional amylin receptor antagonist to reverse the effects of Aβ1-42 and human amylin on LTP and also increases LTP in transgenic mice that demonstrate increased ambient brain amyloid levels. Amylin receptor antagonists may thus serve as potentially useful therapeutic agents in treatment of AD.
Collapse
Affiliation(s)
- R Kimura
- Faculty of Engineering, Tokyo University of Science, Yamaguchi, Sanyo-onoda, Yamaguchi, Japan
- Department of Medicine (Neurology), University of Alberta, Edmonton, AB, T6G 2S2, Canada
| | - D MacTavish
- Department of Medicine (Neurology), University of Alberta, Edmonton, AB, T6G 2S2, Canada
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, T6G 2S2, Canada
| | - J Yang
- Department of Medicine (Neurology), University of Alberta, Edmonton, AB, T6G 2S2, Canada
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, T6G 2S2, Canada
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB, T6G 2S2, Canada
| | - D Westaway
- Department of Medicine (Neurology), University of Alberta, Edmonton, AB, T6G 2S2, Canada
- Department of Biochemistry, University of Alberta, Edmonton, AB, T6G 2S2, Canada
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, T6G 2S2, Canada
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB, T6G 2S2, Canada
| | - Jack H Jhamandas
- Department of Medicine (Neurology), University of Alberta, Edmonton, AB, T6G 2S2, Canada.
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, T6G 2S2, Canada.
| |
Collapse
|
245
|
Kimball BA, Wilson DA, Wesson DW. Alterations of the volatile metabolome in mouse models of Alzheimer's disease. Sci Rep 2016; 6:19495. [PMID: 26762470 PMCID: PMC4725859 DOI: 10.1038/srep19495] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Accepted: 12/14/2015] [Indexed: 12/17/2022] Open
Abstract
In the present study, we tested whether the volatile metabolome was altered by mutations of the Alzheimer's disease (AD)-implicated amyloid precursor protein gene (APP) and comprehensively examined urinary volatiles that may potentially serve as candidate biomarkers of AD. Establishing additional biomarkers in screening populations for AD will provide enhanced diagnostic specificity and will be critical in evaluating disease-modifying therapies. Having strong evidence of gross changes in the volatile metabolome of one line of APP mice, we utilized three unique mouse lines which over-express human mutations of the APP gene and their respective non-transgenic litter-mates (NTg). Head-space gas chromatography/mass spectrometry (GC/MS) of urinary volatiles uncovered several aberrant chromatographic peak responses. We later employed linear discrimination analysis and found that the GC/MS peak responses provide accurate (>84%) genotype classification of urinary samples. These initial data in animal models show that mutant APP gene expression entails a uniquely identifiable urinary odor, which if uncovered in clinical AD populations, may serve as an additional biomarker for the disease.
Collapse
Affiliation(s)
- Bruce A. Kimball
- United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, National Wildlife Research Center, Monell Chemical Senses Center, Philadelphia, PA 19104
| | - Donald A. Wilson
- Emotional Brain Institute, Nathan S. Kline Institute for Psychiatric Research, Orangeburg, NY, 10962
- Department of Child & Adolescent Psychiatry, New York University School of Medicine, New York, NY, 10016
| | - Daniel W. Wesson
- Department of Neurosciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106
- Department of Biology, Case Western Reserve University, Cleveland, OH 44106
| |
Collapse
|
246
|
Impaired Cholinergic Excitation of Prefrontal Attention Circuitry in the TgCRND8 Model of Alzheimer's Disease. J Neurosci 2016; 35:12779-91. [PMID: 26377466 DOI: 10.1523/jneurosci.4501-14.2015] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
UNLABELLED Attention deficits in Alzheimer's disease can exacerbate its other cognitive symptoms, yet relevant disruptions of key prefrontal circuitry are not well understood. Here, in the TgCRND8 mouse model of this neurological disorder, we demonstrate and characterize a disruption of cholinergic excitation in the major corticothalamic layer of the prefrontal cortex, in which modulation by acetylcholine is essential for optimal attentional function. Using electrophysiology with concurrent multiphoton imaging, we show that layer 6 pyramidal cells are unable to sustain cholinergic excitation to the same extent as their nontransgenic littermate controls, as a result of the excessive activation of calcium-activated hyperpolarizing conductances. We report that cholinergic excitation can be improved in TgCRND8 cortex by pharmacological blockade of SK channels, suggesting a novel target for the treatment of cognitive dysfunction in Alzheimer's disease. SIGNIFICANCE STATEMENT Alzheimer's disease is accompanied by attention deficits that exacerbate its other cognitive symptoms. In brain slices of a mouse model of this neurological disorder, we demonstrate, characterize, and rescue impaired cholinergic excitation of neurons essential for optimal attentional performance. In particular, we show that the excessive activation of a calcium-activated potassium conductance disrupts the acetylcholine excitation of prefrontal layer 6 pyramidal neurons and that its blockade normalizes responses. These findings point to a novel potential target for the treatment of cognitive dysfunction in Alzheimer's disease.
Collapse
|
247
|
Better Utilization of Mouse Models of Neurodegenerative Diseases in Preclinical Studies: From the Bench to the Clinic. Methods Mol Biol 2016; 1438:311-47. [PMID: 27150098 DOI: 10.1007/978-1-4939-3661-8_18] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The major symptom of Alzheimer's disease is dementia progressing with age. Its clinical diagnosis is preceded by a long prodromal period of brain pathology that encompasses both formation of extracellular amyloid and intraneuronal tau deposits in the brain and widespread neuronal death. At present, familial cases of dementia provide the most promising foundation for modeling neurodegenerative tauopathies, a group of heterogeneous disorders characterized by prominent intracellular accumulation of hyperphosphorylated tau protein. In this chapter, we describe major behavioral hallmarks of tauopathies, briefly outline the genetics underlying familial cases, and discuss the arising implications for modeling the disease in transgenic mouse systems. The selection of tests performed to evaluate the phenotype of a model should be guided by the key behavioral hallmarks that characterize human disorder and their homology to mouse cognitive systems. We attempt to provide general guidelines and establish criteria for modeling dementia in a mouse; however, interpretations of obtained results should avoid a reductionist "one gene, one disease" explanation of model characteristics. Rather, the focus should be directed to the question of how the mouse genome can cope with the over-expression of the protein coded by transgene(s). While each model is valuable within its own constraints and the experiments performed are guided by specific hypotheses, we seek to expand upon their methodology by offering guidance spanning from issues of mouse husbandry to choices of behavioral tests and routes of drug administration that might increase the external validity of studies and consequently optimize the translational aspect of preclinical research.
Collapse
|
248
|
Abstract
Dementias are among the most common neurological disorders, and Alzheimer's disease (AD) is the most common cause of dementia worldwide. AD remains a looming health crisis despite great efforts to learn the mechanisms surrounding the neuron dysfunction and neurodegeneration that accompanies AD primarily in the medial temporal lobe. In addition to AD, a group of diseases known as frontotemporal dementias (FTDs) are degenerative diseases involving atrophy and degeneration in the frontal and temporal lobe regions. Importantly, AD and a number of FTDs are collectively known as tauopathies due to the abundant accumulation of pathological tau inclusions in the brain. The precise role tau plays in disease pathogenesis remains an area of strong research focus. A critical component to effectively study any human disease is the availability of models that recapitulate key features of the disease. Accordingly, a number of animal models are currently being pursued to fill the current gaps in our knowledge of the causes of dementias and to develop effective therapeutics. Recent developments in gene therapy-based approaches, particularly in recombinant adeno-associated viruses (rAAVs), have provided new tools to study AD and other related neurodegenerative disorders. Additionally, gene therapy approaches have emerged as an intriguing possibility for treating these diseases in humans. This chapter explores the current state of rAAV models of AD and other dementias, discuss recent efforts to improve these models, and describe current and future possibilities in the use of rAAVs and other viruses in treatments of disease.
Collapse
Affiliation(s)
- Benjamin Combs
- Department of Translational Science and Molecular Medicine, College of Human Medicine, Michigan State University, 333 Bostwick Avenue NE, Grand Rapids, MI, 49503, USA
| | - Andrew Kneynsberg
- Department of Translational Science and Molecular Medicine, College of Human Medicine, Michigan State University, 333 Bostwick Avenue NE, Grand Rapids, MI, 49503, USA
- Neuroscience Program, Michigan State University, Grand Rapids, MI, USA
| | - Nicholas M Kanaan
- Department of Translational Science and Molecular Medicine, College of Human Medicine, Michigan State University, 333 Bostwick Avenue NE, Grand Rapids, MI, 49503, USA.
- Neuroscience Program, Michigan State University, Grand Rapids, MI, USA.
| |
Collapse
|
249
|
The cell-permeable Aβ1-6A2VTAT(D) peptide reverts synaptopathy induced by Aβ1-42wt. Neurobiol Dis 2015; 89:101-11. [PMID: 26721320 DOI: 10.1016/j.nbd.2015.12.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Revised: 12/17/2015] [Accepted: 12/21/2015] [Indexed: 02/07/2023] Open
Abstract
Alzheimer disease (AD) is the most prevalent form of dementia. Loss of hippocampal synapses is the first neurodegenerative event in AD. Synaptic loss has been associated with the accumulation in the brain parenchyma of soluble oligomeric forms of amyloid β peptide (Aβ1-42wt). Clinical observations have shown that a mutation in the APP protein (A673V) causes an early onset AD-type dementia in homozygous carriers while heterozygous carriers are unaffected. This mutation leads to the formation of mutated Aβ peptides (Aβ1-42A2V) in homozygous patients, while in heterozygous subjects both Aβ1-42wt and Aβ1-42A2V are present. To better understand the impact of the A673V mutation in AD, we analyzed the synaptotoxic effect of oligomers formed by aggregation of different Aβ peptides (Aβ1-42wt or Aβ1-42A2V) and the combination of the two Aβ1-42MIX (Aβ1-42wt and Aβ1-42A2V) in an in vitro model of synaptic injury. We showed that Aβ1-42A2V oligomers are more toxic than Aβ1-42wt oligomers in hippocampal neurons, confirming the results previously obtained in cell lines. Furthermore, we reported that oligomers obtained by the combination of both wild type and mutated peptides (Aβ1-42MIX) did not exert synaptic toxicity. We concluded that the combination of Aβ1-42wt and Aβ1-42A2V peptides hinders the toxicity of Aβ1-42A2V and counteracts the manifestation of synaptopathy in vitro. Finally we took advantage of this finding to generate a cell-permeable peptide for clinical application, by fusing the first six residues of the Aβ1-42A2V to the TAT cargo sequence (Aβ1-6A2VTAT(D)). Noteworthy, the treatment with Aβ1-6A2VTAT(D) confers neuroprotection against both in vitro and in vivo synaptopathy models. Therefore Aβ1-6A2VTAT(D) may represent an innovative therapeutic tool to prevent synaptic degeneration in AD.
Collapse
|
250
|
Sanchez-Mut JV, Gräff J. Epigenetic Alterations in Alzheimer's Disease. Front Behav Neurosci 2015; 9:347. [PMID: 26734709 PMCID: PMC4681781 DOI: 10.3389/fnbeh.2015.00347] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Accepted: 11/25/2015] [Indexed: 12/11/2022] Open
Abstract
Alzheimer’s disease (AD) is the major cause of dementia in Western societies. It progresses asymptomatically during decades before being belatedly diagnosed when therapeutic strategies have become unviable. Although several genetic alterations have been associated with AD, the vast majority of AD cases do not show strong genetic underpinnings and are thus considered a consequence of non-genetic factors. Epigenetic mechanisms allow for the integration of long-lasting non-genetic inputs on specific genetic backgrounds, and recently, a growing number of epigenetic alterations in AD have been described. For instance, an accumulation of dysregulated epigenetic mechanisms in aging, the predominant risk factor of AD, might facilitate the onset of the disease. Likewise, mutations in several enzymes of the epigenetic machinery have been associated with neurodegenerative processes that are altered in AD such as impaired learning and memory formation. Genome-wide and locus-specific epigenetic alterations have also been reported, and several epigenetically dysregulated genes validated by independent groups. From these studies, a picture emerges of AD as being associated with DNA hypermethylation and histone deacetylation, suggesting a general repressed chromatin state and epigenetically reduced plasticity in AD. Here we review these recent findings and discuss several technical and methodological considerations that are imperative for their correct interpretation. We also pay particular focus on potential implementations and theoretical frameworks that we expect will help to better direct future studies aimed to unravel the epigenetic participation in AD.
Collapse
Affiliation(s)
- Jose V Sanchez-Mut
- Neuroepigenetics Laboratory - UPGRAEFF, Brain Mind Institute, School of Life Sciences, École Polytechnique Fédérale de Lausanne Lausanne, Switzerland
| | - Johannes Gräff
- Neuroepigenetics Laboratory - UPGRAEFF, Brain Mind Institute, School of Life Sciences, École Polytechnique Fédérale de Lausanne Lausanne, Switzerland
| |
Collapse
|