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Zheng J. Hippocampal neurogenesis and pro-neurogenic therapies for Alzheimer's disease. Animal Model Exp Med 2022; 5:3-14. [PMID: 35229998 PMCID: PMC8879631 DOI: 10.1002/ame2.12212] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 12/24/2021] [Accepted: 01/18/2022] [Indexed: 01/01/2023] Open
Abstract
Adult hippocampal neurogenesis (AHN) facilitates hippocampal circuits plasticity and regulates hippocampus-dependent cognition and emotion. However, AHN malfunction has been widely reported in both human and animal models of Alzheimer's disease (AD), the most common form of dementia in the elderly. Pro-neurogenic therapies including rescuing innate AHN, cell engraftment and glia-neuron reprogramming hold great potential for compensating the neuronal loss and rewiring the degenerated neuronal network in AD, but there are still great challenges to be overcome. This review covers recent advances in unraveling the involvement of AHN in AD and highlights the prospect of emerging pro-neurogenic remedies.
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Affiliation(s)
- Jie Zheng
- Department of PharmacologyKey Laboratory of Basic Pharmacology of Ministry of Education and Joint International Research Laboratory of Ethnomedicine of Ministry of EducationKey Laboratory of Basic Pharmacology of Guizhou ProvinceZunyi Medical UniversityZunyiChina
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2
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Implication of Adult Hippocampal Neurogenesis in Alzheimer’s Disease and Potential Therapeutic Approaches. Cells 2022; 11:cells11020286. [PMID: 35053402 PMCID: PMC8773637 DOI: 10.3390/cells11020286] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 01/11/2022] [Accepted: 01/12/2022] [Indexed: 12/31/2022] Open
Abstract
Alzheimer’s disease is the most common neurodegenerative disease, affecting more than 6 million US citizens and representing the most prevalent cause for dementia. Neurogenesis has been repeatedly reported to be impaired in AD mouse models, but the reason for this impairment remains unclear. Several key factors play a crucial role in AD including Aβ accumulation, intracellular neurofibrillary tangles accumulation, and neuronal loss (specifically in the dentate gyrus of the hippocampus). Neurofibrillary tangles have been long associated with the neuronal loss in the dentate gyrus. Of note, Aβ accumulation plays an important role in the impairment of neurogenesis, but recent studies started to shed a light on the role of APP gene expression on the neurogenesis process. In this review, we will discuss the recent approaches to neurogenesis in Alzheimer disease and update the development of therapeutic methods.
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3
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Treadmill Exercise Ameliorates Adult Hippocampal Neurogenesis Possibly by Adjusting the APP Proteolytic Pathway in APP/PS1 Transgenic Mice. Int J Mol Sci 2021; 22:ijms22179570. [PMID: 34502477 PMCID: PMC8431648 DOI: 10.3390/ijms22179570] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 08/30/2021] [Accepted: 08/31/2021] [Indexed: 12/19/2022] Open
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder known to cause cognitive impairment among the elderly worldwide. Although physical exercise-induced adult hippocampal neurogenesis (AHN) improves cognition, understanding its underlying molecular mechanisms requires further investigation using AD mouse models. In this present work, we subjected amyloid precursor protein (APP)/PS1 mice to a 12-week aerobic treadmill exercise to investigate AHN and its potential mechanisms. We divided 3-month-old littermates wild-type and APP/PS1 transgenic male mice into four groups, and the exercise groups performed 12-week treadmill exercise. Next, we evaluated the influence of treadmill exercise on learning and memory capacity, AHN, and APP proteolytic pathway-related factors. As per our results, the treadmill exercise was able to improve the hippocampal microenvironment in APP/PS1 mice probably by regulating various neurotrophic factors and secretases resulting in APP cleavage through a non-amyloidogenic pathway, which seems to further promote new cell proliferation, survival, and differentiation, enhancing hippocampal neurogenesis. All of these effects ameliorate learning and memory capacity. This study provides a theoretical and experimental basis for understanding AHN in an AD mouse model, which is beneficial for preventing and treating AD.
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4
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Paulo SL, Ribeiro-Rodrigues L, Rodrigues RS, Mateus JM, Fonseca-Gomes J, Soares R, Diógenes MJ, Solá S, Sebastião AM, Ribeiro FF, Xapelli S. Sustained Hippocampal Neural Plasticity Questions the Reproducibility of an Amyloid-β-Induced Alzheimer's Disease Model. J Alzheimers Dis 2021; 82:1183-1202. [PMID: 34151790 DOI: 10.3233/jad-201567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND The use of Alzheimer's disease (AD) models obtained by intracerebral infusion of amyloid-β (Aβ) has been increasingly reported in recent years. Nonetheless, these models may present important challenges. OBJECTIVE We have focused on canonical mechanisms of hippocampal-related neural plasticity to characterize a rat model obtained by an intracerebroventricular (icv) injection of soluble amyloid-β42 (Aβ42). METHODS Animal behavior was evaluated in the elevated plus maze, Y-Maze spontaneous or forced alternation, Morris water maze, and open field, starting 2 weeks post-Aβ42 infusion. Hippocampal neurogenesis was assessed 3 weeks after Aβ42 injection. Aβ deposition, tropomyosin receptor kinase B levels, and neuroinflammation were appraised at 3 and 14 days post-Aβ42 administration. RESULTS We found that immature neuronal dendritic morphology was abnormally enhanced, but proliferation and neuronal differentiation in the dentate gyrus was conserved one month after Aβ42 injection. Surprisingly, animal behavior did not reveal changes in cognitive performance nor in locomotor and anxious-related activity. Brain-derived neurotrophic factor related-signaling was also unchanged at 3 and 14 days post-Aβ icv injection. Likewise, astrocytic and microglial markers of neuroinflammation in the hippocampus were unaltered in these time points. CONCLUSION Taken together, our data emphasize a high variability and lack of behavioral reproducibility associated with these Aβ injection-based models, as well as the need for its further optimization, aiming at addressing the gap between preclinical AD models and the human disorder.
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Affiliation(s)
- Sara L Paulo
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal.,Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Leonor Ribeiro-Rodrigues
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal.,Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Rui S Rodrigues
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal.,Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Joana M Mateus
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal.,Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - João Fonseca-Gomes
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal.,Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Rita Soares
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal.,Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal.,Instituto de Biologia Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Maria J Diógenes
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal.,Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Susana Solá
- Research Institute for Medicines (iMed.ULisboa), Faculdade de Farmácia, Universidade de Lisboa, Lisboa, Portugal
| | - Ana M Sebastião
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal.,Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Filipa F Ribeiro
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal.,Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Sara Xapelli
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal.,Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
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5
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Gerberding AL, Zampar S, Stazi M, Liebetanz D, Wirths O. Physical Activity Ameliorates Impaired Hippocampal Neurogenesis in the Tg4-42 Mouse Model of Alzheimer's Disease. ASN Neuro 2020; 11:1759091419892692. [PMID: 31818124 PMCID: PMC6906584 DOI: 10.1177/1759091419892692] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
There is growing evidence from epidemiological studies that especially midlife physical activity might exert a positive influence on the risk and progression of Alzheimer’s disease. In this study, the Tg4-42 mouse model of Alzheimer’s disease has been utilized to assess the effect of different housing conditions on structural changes in the hippocampus. Focusing on the dentate gyrus, we demonstrate that 6-month-old Tg4-42 mice have a reduced number of newborn neurons in comparison to age-matched wild-type mice. Housing these mice for 4 months with either unlimited or intermittent access to a running wheel resulted in a significant rescue of dentate gyrus neurogenesis. Although neither dentate gyrus volume nor neuron number could be modified in this Alzheimer’s disease mouse model, unrestricted access to a running wheel significantly increased dentate gyrus volume and granule cell number in wild-type mice.
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Affiliation(s)
- Anna-Lina Gerberding
- Department of Psychiatry and Psychotherapy, Molecular Psychiatry, University Medical Center (UMG), Georg-August-University, Göttingen, Germany
| | - Silvia Zampar
- Department of Psychiatry and Psychotherapy, Molecular Psychiatry, University Medical Center (UMG), Georg-August-University, Göttingen, Germany
| | - Martina Stazi
- Department of Psychiatry and Psychotherapy, Molecular Psychiatry, University Medical Center (UMG), Georg-August-University, Göttingen, Germany
| | - David Liebetanz
- Department of Clinical Neurophysiology, University Medical Center (UMG), Georg-August-University, Göttingen, Germany
| | - Oliver Wirths
- Department of Psychiatry and Psychotherapy, Molecular Psychiatry, University Medical Center (UMG), Georg-August-University, Göttingen, Germany
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6
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Interneuron Accumulation of Phosphorylated tau Impairs Adult Hippocampal Neurogenesis by Suppressing GABAergic Transmission. Cell Stem Cell 2020; 26:331-345.e6. [PMID: 31978364 DOI: 10.1016/j.stem.2019.12.015] [Citation(s) in RCA: 81] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 10/27/2019] [Accepted: 12/12/2019] [Indexed: 12/27/2022]
Abstract
Phospho-tau accumulation and adult hippocampal neurogenesis (AHN) impairment both contribute importantly to the cognitive decline in Alzheimer's disease (AD), but whether and how tau dysregulates AHN in AD remain poorly understood. Here, we found a prominent accumulation of phosphorylated tau in GABAergic interneurons in the dentate gyrus (DG) of AD patients and mice. Specific overexpression of human tau (hTau) in mice DG interneurons induced AHN deficits but increased neural stem cell-derived astrogliosis, associating with a downregulation of GABA and hyperactivation of neighboring excitatory neurons. Chemogenetic inhibition of excitatory neurons or pharmacologically strengthening GABAergic tempos rescued the tau-induced AHN deficits and improved contextual cognition. These findings evidenced that intracellular accumulation of tau in GABAergic interneurons impairs AHN by suppressing GABAergic transmission and disinhibiting neural circuits within the neurogenic niche, suggesting a potential of GABAergic potentiators for pro-neurogenic or cell therapies of AD.
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Sri S, Pegasiou CM, Cave CA, Hough K, Wood N, Gomez-Nicola D, Deinhardt K, Bannerman D, Perry VH, Vargas-Caballero M. Emergence of synaptic and cognitive impairment in a mature-onset APP mouse model of Alzheimer's disease. Acta Neuropathol Commun 2019; 7:25. [PMID: 30795807 PMCID: PMC6387506 DOI: 10.1186/s40478-019-0670-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 01/29/2019] [Indexed: 01/10/2023] Open
Abstract
The synaptic changes underlying the onset of cognitive impairment in Alzheimer’s disease (AD) are poorly understood. In contrast to the well documented inhibition of long-term potentiation (LTP) in CA3-CA1 synapses by acute Aβ application in adult neurons from rodents, young amyloid precursor protein (APP) transgenic mouse models often, surprisingly, show normal LTP. This suggests that there may be important differences between mature-onset and developmental-onset APP expression/ Aβ accumulation and the ensuing synaptic and behavioural phenotype. Here, in agreement with previous studies, we observed that developmental expression of APPSw,Ind (3–4 month old mice from line 102, PLoS Med 2:e355, 2005), resulted in reduced basal synaptic transmission in CA3-CA1 synapses, normal LTP, impaired spatial working memory, but normal spatial reference memory. To analyse early Aβ-mediated synaptic dysfunction and cognitive impairment in a more mature brain, we used controllable mature-onset APPSw,Ind expression in line 102 mice. Within 3 weeks of mature-onset APPSw,Ind expression and Aβ accumulation, we detected the first synaptic dysfunction: an impairment of LTP in hippocampal CA3-CA1 synapses. Cognitively, at this time point, we observed a deficit in short-term memory. A reduction in basal synaptic strength and deficit in long-term associative spatial memory were only evident following 12 weeks of APPSw,Ind expression. Importantly, the plasticity impairment observed after 3 weeks of mature-onset APP expression is reversible. Together, these findings demonstrate important differences between developmental and mature-onset APP expression. Further research targeted at this early stage of synaptic dysfunction could help identify mechanisms to treat cognitive impairment in mild cognitive impairment (MCI) and early AD.
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El-Magd MA, Khalifa SF, A Alzahrani FA, Badawy AA, El-Shetry ES, Dawood LM, Alruwaili MM, Alrawaili HA, Risha EF, El-Taweel FM, Marei HE. Incensole acetate prevents beta-amyloid-induced neurotoxicity in human olfactory bulb neural stem cells. Biomed Pharmacother 2018; 105:813-823. [PMID: 29913410 DOI: 10.1016/j.biopha.2018.06.014] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 06/02/2018] [Accepted: 06/03/2018] [Indexed: 12/17/2022] Open
Abstract
β-Amyloid peptide (Aβ) is a potent neurotoxic protein associated with Alzheimer's disease (AD) which causes oxidative damage to neurons. Incensole acetate (IA) is a major constituent of Boswellia carterii resin, which has anti-inflammatory and protective properties against damage of a large verity of neural subtypes. However, this neuroprotective effect was not studied on human olfactory bulb neural stem cells (hOBNSCs). Herein, we evaluated this effect and studied the underlying mechanisms. Exposure to Aβ25-35 (5 and 10 μM for 24 h) inhibited proliferation (revealed by downregulation of Nestin and Sox2 gene expression), and induced differentiation (marked by increased expression of the immature neuronal marker Map2 and the astrocyte marker Gfap) of hOBNSCs. However, pre-treatment with IA (100 μM for 4 h) stimulated proliferation and differentiation of neuronal, rather than astrocyte, markers. Moreover, IA pretreatment significantly decreased the Aβ25-35-induced viability loss, apoptotic rate (revealed by decreased caspase 3 activity and protein expression, downregulated expression of Bax, caspase 8, cyto c, caspase3, and upregulated expression of Bcl2 mRNAs and proteins, in addition to elevated mitochondrial membrane potential and lowered intracellular Ca+2). IA reduced Aβ-mediated ROS production (revealed by decreased intracellular ROS and MDA level, and increased SOD, CAT, and GPX contents), and inhibited Aβ-induced inflammation (marked by down-regulated expression of IL1b, TNFa, NfKb, and Cox2 genes). IA also significantly upregulated mRNA and protein expression of Erk1/2 and Nrf2. Notably, IA increased the antioxidant enzyme heme oxygenase-1 (HO-1) expression and this effect was reversed by HO-1 inhibitor zinc protoporphyrin (ZnPP) leading to reduction of the neuroprotective effect of IA against Aβ-induced neurotoxicity. These findings clearly show the ability of IA to initiate proliferation and differentiation of neuronal progenitors in hOBNSCs and induce HO-1 expression, thereby protecting the hOBNSCs cells from Aβ25-35-induced oxidative cell death. Thus, IA may be applicable as a potential preventive agent for AD by its effect on hOBNSCs and could also be used as an adjuvant to hOBNSCs in cellular therapy of neurodegenerative diseases.
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Affiliation(s)
- Mohammed A El-Magd
- Department of Anatomy, Faculty of Veterinary Medicine, Kafrelsheikh University, Egypt.
| | - Sara F Khalifa
- Department of Chemistry, Faculty of Science, Damietta University, Egypt
| | - Faisal Abdulrahman A Alzahrani
- Department of Biological Sciences, Rabigh College of Science and Arts, King Abdulaziz University (Jeddah), Rabigh Branch, Rabigh 21911, Saudi Arabia
| | - Abdelnaser A Badawy
- Department of Medical Biochemistry, Faculty of Medicine, Mansoura University, Egypt
| | - Eman S El-Shetry
- Department of Human Anatomy, Faculty of Medicine, Zagazig University, Egypt
| | - Lamess M Dawood
- Department of Biochemistry, Faculty of Medicine, Tanta University, Egypt
| | - Mohammed M Alruwaili
- Medical Laboratory Technology Department, Faculty of Applied Medical Biosciences, Northern Border University, Arar City, Saudi Arabia
| | - Hedib A Alrawaili
- Medical Laboratory Sciences Department, School of Health Sciences, Quinnipiac University, Hamden, CT, USA
| | - Engi F Risha
- Department of Clinical Pathology, Faculty of Veterinary Medicine, Mansoura University, Egypt
| | - Fathy M El-Taweel
- Department of Chemistry, Faculty of Science, Damietta University, Egypt
| | - Hany E Marei
- Department of Cytology and Histology, Faculty of Veterinary Medicine, Mansoura University, Egypt
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Regensburger M, Schreglmann SR, Stoll S, Rockenstein E, Loskarn S, Xiang W, Masliah E, Winner B. Oligomer-prone E57K-mutant alpha-synuclein exacerbates integration deficit of adult hippocampal newborn neurons in transgenic mice. Brain Struct Funct 2017; 223:1357-1368. [PMID: 29124353 PMCID: PMC5869938 DOI: 10.1007/s00429-017-1561-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Accepted: 11/02/2017] [Indexed: 11/26/2022]
Abstract
In the adult mammalian hippocampus, new neurons are constantly added to the dentate gyrus. Adult neurogenesis is impaired in several neurodegenerative mouse models including α-synuclein (a-syn) transgenic mice. Among different a-syn species, a-syn oligomers were reported to be the most toxic species for neurons. Here, we studied the impact of wild-type vs. oligomer-prone a-syn on neurogenesis. We compared the wild-type a-syn transgenic mouse model (Thy1-WTS) to its equivalent transgenic for oligomer-prone E57K-mutant a-syn (Thy1-E57K). Transgenic a-syn was highly expressed within the hippocampus of both models, but was not present within adult neural stem cells and neuroblasts. Proliferation and survival of newly generated neurons were unchanged in both transgenic models. Thy1-WTS showed a minor integration deficit regarding mushroom spine density of newborn neurons, whereas Thy1-E57K exhibited a severe reduction of all spines. We conclude that cell-extrinsic a-syn impairs mushroom spine formation of adult newborn neurons and that oligomer-prone a-syn exacerbates this integration deficit. Moreover, our data suggest that a-syn reduces the survival of newborn neurons by a cell-intrinsic mechanism during the early neuroblast development. The finding of increased spine pathology in Thy1-E57K is a new pathogenic function of oligomeric a-syn and precedes overt neurodegeneration. Thus, it may constitute a readout for therapeutic approaches.
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Affiliation(s)
- Martin Regensburger
- Department of Stem Cell Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
- IZKF Junior Research Group III, and BMBF Research Group Neuroscience, FAU, Erlangen, Germany
- Department of Neurology, FAU, Erlangen, Germany
| | - Sebastian R Schreglmann
- School of Medicine, University of Regensburg, Regensburg, Germany
- Sobell Department of Motor Neuroscience and Movement Disorders, Institute of Neurology, UCL, London, UK
| | - Svenja Stoll
- Department of Stem Cell Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
- IZKF Junior Research Group III, and BMBF Research Group Neuroscience, FAU, Erlangen, Germany
| | - Edward Rockenstein
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA
| | - Sandra Loskarn
- Department of Stem Cell Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany
- IZKF Junior Research Group III, and BMBF Research Group Neuroscience, FAU, Erlangen, Germany
- Department of Neurology, FAU, Erlangen, Germany
| | - Wei Xiang
- Institute of Biochemistry, FAU, Erlangen, Germany
| | - Eliezer Masliah
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA
| | - Beate Winner
- Department of Stem Cell Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen, Germany.
- IZKF Junior Research Group III, and BMBF Research Group Neuroscience, FAU, Erlangen, Germany.
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10
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Amin H, Nieus T, Lonardoni D, Maccione A, Berdondini L. High-resolution bioelectrical imaging of Aβ-induced network dysfunction on CMOS-MEAs for neurotoxicity and rescue studies. Sci Rep 2017; 7:2460. [PMID: 28550283 PMCID: PMC5446416 DOI: 10.1038/s41598-017-02635-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 05/03/2017] [Indexed: 11/20/2022] Open
Abstract
Neurotoxicity and the accumulation of extracellular amyloid-beta1–42 (Aβ) peptides are associated with the development of Alzheimer’s disease (AD) and correlate with neuronal activity and network dysfunctions, ultimately leading to cellular death. However, research on neurodegenerative diseases is hampered by the paucity of reliable readouts and experimental models to study such functional decline from an early onset and to test rescue strategies within networks at cellular resolution. To overcome this important obstacle, we demonstrate a simple yet powerful in vitro AD model based on a rat hippocampal cell culture system that exploits large-scale neuronal recordings from 4096-electrodes on CMOS-chips for electrophysiological quantifications. This model allows us to monitor network activity changes at the cellular level and to uniquely uncover the early activity-dependent deterioration induced by Aβ-neurotoxicity. We also demonstrate the potential of this in vitro model to test a plausible hypothesis underlying the Aβ-neurotoxicity and to assay potential therapeutic approaches. Specifically, by quantifying N-methyl D-aspartate (NMDA) concentration-dependent effects in comparison with low-concentration allogenic-Aβ, we confirm the role of extrasynaptic-NMDA receptors activation that may contribute to Aβ-neurotoxicity. Finally, we assess the potential rescue of neural stem cells (NSCs) and of two pharmacotherapies, memantine and saffron, for reversing Aβ-neurotoxicity and rescuing network-wide firing.
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Affiliation(s)
- Hayder Amin
- Nets3 Laboratory, Departement of Neuroscience & Brain Technologies (NBT), Fondazione Istituto Italiano di Tecnologia (IIT), via morego 30, 16163, Genova, Italy.
| | - Thierry Nieus
- Nets3 Laboratory, Departement of Neuroscience & Brain Technologies (NBT), Fondazione Istituto Italiano di Tecnologia (IIT), via morego 30, 16163, Genova, Italy
| | - Davide Lonardoni
- Nets3 Laboratory, Departement of Neuroscience & Brain Technologies (NBT), Fondazione Istituto Italiano di Tecnologia (IIT), via morego 30, 16163, Genova, Italy
| | - Alessandro Maccione
- Nets3 Laboratory, Departement of Neuroscience & Brain Technologies (NBT), Fondazione Istituto Italiano di Tecnologia (IIT), via morego 30, 16163, Genova, Italy
| | - Luca Berdondini
- Nets3 Laboratory, Departement of Neuroscience & Brain Technologies (NBT), Fondazione Istituto Italiano di Tecnologia (IIT), via morego 30, 16163, Genova, Italy
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11
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Wirths O. Altered neurogenesis in mouse models of Alzheimer disease. NEUROGENESIS 2017; 4:e1327002. [PMID: 29564360 DOI: 10.1080/23262133.2017.1327002] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Revised: 04/28/2017] [Accepted: 04/28/2017] [Indexed: 10/19/2022]
Abstract
Amyloid-β (Aβ) peptides, as well as a variety of other protein fragments, are derived from proteolytical cleavage of the amyloid precursor protein (APP) and have been demonstrated to play a key role in the pathological changes underlying Alzheimer disease (AD). In AD mouse models, altered neurogenesis has been repeatedly reported to be associated with further AD-typical pathological hallmarks such as extracellular plaque deposition, behavioral deficits or neuroinflammation. While a toxic role of Aβ in neurodegeneration and impaired neuronal progenitor proliferation is likely and well-accepted, recent findings also suggest an important influence of APP-derived proteolitical fragments like the APP intracellular domain (AICD), as well as of APP itself.
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Affiliation(s)
- Oliver Wirths
- Division of Molecular Psychiatry, Department of Psychiatry and Psychotherapy, University Medical Center (UMG), Georg-August-University, Göttingen, Germany
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12
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Exosomes Secreted from HEK293-APP Swe/Ind Cells Impair the Hippocampal Neurogenesis. Neurotox Res 2017; 32:82-93. [DOI: 10.1007/s12640-017-9713-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 02/21/2017] [Accepted: 02/23/2017] [Indexed: 11/25/2022]
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13
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Hong XP, Chen T, Yin NN, Han YM, Yuan F, Duan YJ, Shen F, Zhang YH, Chen ZB. Puerarin Ameliorates D-Galactose Induced Enhanced Hippocampal Neurogenesis and Tau Hyperphosphorylation in Rat Brain. J Alzheimers Dis 2016; 51:605-17. [PMID: 26890737 DOI: 10.3233/jad-150566] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Enhanced neurogenesis has been reported in the hippocampus of patients with Alzheimer's disease (AD), the most common neurodegenerative disorder characterized with amyloid-β (Aβ) aggregation, tau hyperphosphorylation, and progressive neuronal loss. Previously we reported that tau phosphorylation played an essential role in adult hippocampal neurogenesis, and activation of glycogen synthase kinase (GSK-3), a crucial tau kinase, could induce increased hippocampal neurogenesis. In the present study, we found that treatment of D-galactose rats with Puerarin could significantly improve behavioral performance and ameliorate the enhanced neurogenesis and microtubule-associated protein tau hyperphosphorylation in the hippocampus of D-galactose rat brains. FGF-2/GSK-3 signaling pathway might be involved in the effects of Puerarin on hippocampal neurogenesis and tau hyperphosphorylation. Our finding provides primary in vivo evidence that Puerarin can attenuate AD-like enhanced hippocampal neurogenesis and tau hyperphosphorylation. Our finding also suggests Puerarin can be served as a treatment for age-related neurodegenerative disorders, such as AD.
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Affiliation(s)
- Xiao-Ping Hong
- Department of Anatomy and Histology, College of Basic Medicine, Hubei University of Chinese Medicine, Wuhan, People's Republic of China
| | - Tao Chen
- Department of Anatomy and Histology, College of Basic Medicine, Hubei University of Chinese Medicine, Wuhan, People's Republic of China
| | - Ni-Na Yin
- Department of Anatomy and Histology, College of Basic Medicine, Hubei University of Chinese Medicine, Wuhan, People's Republic of China
| | - Yong-Ming Han
- Department of Anatomy and Histology, College of Basic Medicine, Hubei University of Chinese Medicine, Wuhan, People's Republic of China
| | - Fang Yuan
- Central Laboratory of College of Basic Medicine, Hubei University of Chinese Medicine, Wuhan, People's Republic of China
| | - Yan-Jun Duan
- Department of Anatomy and Histology, College of Basic Medicine, Hubei University of Chinese Medicine, Wuhan, People's Republic of China
| | - Feng Shen
- Department of Acupuncture and Moxibustion, College of Acupuncture and Orthopedics, Hubei University of Chinese Medicine, Wuhan, People's Republic of China
| | - Yan-Hong Zhang
- Department of Anatomy and Histology, College of Basic Medicine, Hubei University of Chinese Medicine, Wuhan, People's Republic of China
| | - Ze-Bin Chen
- Department of Anatomy and Histology, College of Basic Medicine, Hubei University of Chinese Medicine, Wuhan, People's Republic of China
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14
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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.
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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
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15
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Pan H, Wang D, Zhang X, Zhou D, Zhang H, Qian Q, He X, Liu Z, Liu Y, Zheng T, Zhang L, Wang M, Sun B. Amyloid β Is Not the Major Factor Accounting for Impaired Adult Hippocampal Neurogenesis in Mice Overexpressing Amyloid Precursor Protein. Stem Cell Reports 2016; 7:707-718. [PMID: 27693425 PMCID: PMC5063569 DOI: 10.1016/j.stemcr.2016.08.019] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Revised: 08/30/2016] [Accepted: 08/31/2016] [Indexed: 11/22/2022] Open
Abstract
Adult hippocampal neurogenesis was impaired in several Alzheimer's disease models overexpressing mutant human amyloid precursor protein (hAPP). However, the effects of wild-type hAPP on adult neurogenesis and whether the impaired adult hippocampal neurogenesis was caused by amyloid β (Aβ) or APP remained unclear. Here, we found that neurogenesis was impaired in the dentate gyrus (DG) of adult mice overexpressing wild-type hAPP (hAPP-I5) compared with controls. However, the adult hippocampal neurogenesis was more severely impaired in hAPP-I5 than that in hAPP-J20 mice, which express similar levels of hAPP mRNA but much higher levels of Aβ. Furthermore, reducing Aβ levels did not affect the number of doublecortin-positive cells in the DG of hAPP-J20 mice. Our results suggested that hAPP was more likely an important factor inhibiting adult neurogenesis, and Aβ was not the major factor affecting neurogenesis in the adult hippocampus of hAPP mice. Overexpression of wild-type hAPP impairs adult hippocampal neurogenesis Adult hippocampal neurogenesis was more severely impaired in hAPP-I5 than in hAPP-J20 Reducing Aβ levels did not affect adult neurogenesis in hAPP-J20 mice Aβ is not the major factor accounting for impaired adult neurogenesis in hAPP mice
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Affiliation(s)
- Hongyu Pan
- Department of Neurobiology, School of Basic Medical Sciences, Key Laboratory of Medical Neurobiology (Ministry of Health of China), Key Laboratory of Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province 310058, China
| | - Dongpi Wang
- Department of Neurobiology, School of Basic Medical Sciences, Key Laboratory of Medical Neurobiology (Ministry of Health of China), Key Laboratory of Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province 310058, China
| | - Xiaoqin Zhang
- Department of Neurobiology, School of Basic Medical Sciences, Key Laboratory of Medical Neurobiology (Ministry of Health of China), Key Laboratory of Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province 310058, China
| | - Dongming Zhou
- Department of Neurobiology, School of Basic Medical Sciences, Key Laboratory of Medical Neurobiology (Ministry of Health of China), Key Laboratory of Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province 310058, China
| | - Heng Zhang
- Department of Neurobiology, School of Basic Medical Sciences, Key Laboratory of Medical Neurobiology (Ministry of Health of China), Key Laboratory of Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province 310058, China
| | - Qi Qian
- Department of Neurology, Brain Medical Center, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province 310058, China
| | - Xiao He
- Department of Neurobiology, School of Basic Medical Sciences, Key Laboratory of Medical Neurobiology (Ministry of Health of China), Key Laboratory of Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province 310058, China
| | - Zhaoling Liu
- Department of Neurobiology, School of Basic Medical Sciences, Key Laboratory of Medical Neurobiology (Ministry of Health of China), Key Laboratory of Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province 310058, China
| | - Yunjin Liu
- Department of Neurobiology, School of Basic Medical Sciences, Key Laboratory of Medical Neurobiology (Ministry of Health of China), Key Laboratory of Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province 310058, China
| | - Tingting Zheng
- Department of Neurology, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province 310058, China
| | - Ling Zhang
- Department of Neurobiology, School of Basic Medical Sciences, Key Laboratory of Medical Neurobiology (Ministry of Health of China), Key Laboratory of Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province 310058, China
| | - Mingkai Wang
- Department of Neurobiology, School of Basic Medical Sciences, Key Laboratory of Medical Neurobiology (Ministry of Health of China), Key Laboratory of Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province 310058, China
| | - Binggui Sun
- Department of Neurobiology, School of Basic Medical Sciences, Key Laboratory of Medical Neurobiology (Ministry of Health of China), Key Laboratory of Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province 310058, China.
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16
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Melnikova T, Park D, Becker L, Lee D, Cho E, Sayyida N, Tian J, Bandeen-Roche K, Borchelt DR, Savonenko AV. Sex-related dimorphism in dentate gyrus atrophy and behavioral phenotypes in an inducible tTa:APPsi transgenic model of Alzheimer's disease. Neurobiol Dis 2016; 96:171-185. [PMID: 27569580 DOI: 10.1016/j.nbd.2016.08.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Revised: 07/07/2016] [Accepted: 08/16/2016] [Indexed: 02/07/2023] Open
Abstract
Sex differences are a well-known phenomenon in Alzheimer's disease (AD), with women having a higher risk for AD than men. Many AD mouse models display a similar sex-dependent pattern, with females showing earlier cognitive deficits and more severe neuropathology than males. However, whether those differences are relevant to human disease is unclear. Here we show that in AD mouse models that overexpress amyloid precursor protein (APP) under control of the prion protein promoter (PrP), female transgenic mice have higher APP expression than males, complicating interpretations of the role of sex-related factors in such models. By contrast, in a tTa:APPsi model, in which APP expression is driven by the tetracycline transactivator (tTa) from the CaMKIIα promoter, there are no sex-related differences in expression or processing of APP. In addition, the levels of Aβ dimers and tetramers, as well as Aβ peptide accumulation, are similar between sexes. Behavioral testing demonstrated that both male and female tTa:APPsi mice develop age-dependent deficits in spatial recognition memory and conditional freezing to context. These cognitive deficits were accompanied by habituation-associated hyperlocomotion and startle hyper-reactivity. Significant sex-related dimorphisms were observed, due to females showing earlier onsets of the deficits in conditioned freezing and hyperlocomotion. In addition, tTa:APPsi males but not females demonstrated a lack of novelty-induced activation. Both males and females showed atrophy of the dentate gyrus (DG) of the dorsal hippocampus, associated with widening of the pyramidal layer of the CA1 area in both sexes. Ventral DG was preserved. Sex-related differences were limited to the DG, with females showing more advanced degeneration than males. Collectively, our data show that the tTa:APPsi model is characterized by a lack of sex-related differences in APP expression, making this model useful in deciphering the mechanisms of sex differences in AD pathogenesis. Sex-related dimorphisms observed in this model under conditions of equal APP expression between sexes suggest a higher sensitivity of females to the effects of APP and/or Aβ production.
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Affiliation(s)
- Tatiana Melnikova
- Department of Pathology, The Johns Hopkins University School of Medicine, 720 Rutland Ave, Ross 558, Baltimore, MD 21205, USA.
| | - DaMin Park
- Department of Pathology, The Johns Hopkins University School of Medicine, 720 Rutland Ave, Ross 558, Baltimore, MD 21205, USA.
| | - Lauren Becker
- Department of Pathology, The Johns Hopkins University School of Medicine, 720 Rutland Ave, Ross 558, Baltimore, MD 21205, USA.
| | - Deidre Lee
- Department of Pathology, The Johns Hopkins University School of Medicine, 720 Rutland Ave, Ross 558, Baltimore, MD 21205, USA.
| | - Eugenia Cho
- Department of Pathology, The Johns Hopkins University School of Medicine, 720 Rutland Ave, Ross 558, Baltimore, MD 21205, USA.
| | - Nuzhat Sayyida
- Department of Pathology, The Johns Hopkins University School of Medicine, 720 Rutland Ave, Ross 558, Baltimore, MD 21205, USA.
| | - Jing Tian
- Department of Biostatistics, School of Public Health, The Johns Hopkins University, 615 N Wolfe St E3527, Baltimore, MD 21205, USA.
| | - Karen Bandeen-Roche
- Department of Biostatistics, School of Public Health, The Johns Hopkins University, 615 N Wolfe St E3527, Baltimore, MD 21205, USA.
| | - David R Borchelt
- Department of Neuroscience, Center for Translational Research in Neurodegenerative Disease, McKnight Brain Institute, University of Florida, 100 Newell Drive, Gainesville, FL 32610, USA.
| | - Alena V Savonenko
- Department of Pathology, The Johns Hopkins University School of Medicine, 720 Rutland Ave, Ross 558, Baltimore, MD 21205, USA.
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17
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Neural stem/progenitor cells in Alzheimer's disease. THE YALE JOURNAL OF BIOLOGY AND MEDICINE 2016; 89:23-35. [PMID: 27505014 PMCID: PMC4797833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Alzheimer's disease (AD) is the most prevalent neurodegenerative disease and a worldwide health challenge. Different therapeutic approaches are being developed to reverse or slow the loss of affected neurons. Another plausible therapeutic way that may complement the studies is to increase the survival of existing neurons by mobilizing the existing neural stem/progenitor cells (NSPCs) - i.e. "induce their plasticity" - to regenerate lost neurons despite the existing pathology and unfavorable environment. However, there is controversy about how NSPCs are affected by the unfavorable toxic environment during AD. In this review, we will discuss the use of stem cells in neurodegenerative diseases and in particular how NSPCs affect the AD pathology and how neurodegeneration affects NSPCs. In the end of this review, we will discuss how zebrafish as a useful model organism with extensive regenerative ability in the brain might help to address the molecular programs needed for NSPCs to respond to neurodegeneration by enhanced neurogenesis.
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18
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Martinez-Canabal A. Reconsidering hippocampal neurogenesis in Alzheimer's disease. Front Neurosci 2014; 8:147. [PMID: 24966809 PMCID: PMC4052799 DOI: 10.3389/fnins.2014.00147] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Accepted: 05/23/2014] [Indexed: 11/13/2022] Open
Affiliation(s)
- Alonso Martinez-Canabal
- Molecular Neuropathology Department, Cell Physiology Institute, National Autonomous University of Mexico Mexico City, Mexico ; Cell Biology Department, Faculty of Sciences, National Autonomous University of Mexico Mexico City, Mexico
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19
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Dawkins E, Small DH. Insights into the physiological function of the β-amyloid precursor protein: beyond Alzheimer's disease. J Neurochem 2014; 129:756-69. [PMID: 24517464 PMCID: PMC4314671 DOI: 10.1111/jnc.12675] [Citation(s) in RCA: 162] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2014] [Revised: 02/02/2014] [Accepted: 02/03/2014] [Indexed: 12/21/2022]
Abstract
The β-amyloid precursor protein (APP) has been extensively studied for its role as the precursor of the β-amyloid protein (Aβ) of Alzheimer's disease. However, the normal function of APP remains largely unknown. This article reviews studies on the structure, expression and post-translational processing of APP, as well as studies on the effects of APP in vitro and in vivo. We conclude that the published data provide strong evidence that APP has a trophic function. APP is likely to be involved in neural stem cell development, neuronal survival, neurite outgrowth and neurorepair. However, the mechanisms by which APP exerts its actions remain to be elucidated. The available evidence suggests that APP interacts both intracellularly and extracellularly to regulate various signal transduction mechanisms. This article reviews studies on the structure, expression and post-translational processing of β-amyloid precursor protein (APP), as well as studies on the effects of APP in vitro and in vivo. We conclude that the published data provide strong evidence that APP has a trophic function. APP is likely to be involved in neural stem cell development, neuronal survival, neurite outgrowth and neurorepair. However, the mechanisms by which APP exerts its actions remain to be elucidated. The available evidence suggests that APP interacts both intracellularly and extracellularly to regulate various signal transduction mechanisms.
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Affiliation(s)
- Edgar Dawkins
- Menzies Research Institute Tasmania, University of Tasmania, Hobart, Tasmania, Australia
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