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Song C, Li S, Mai Y, Li L, Dai G, Zhou Y, Liang X, Zou OM, Wang Y, Zhou L, Liu J, Zou Y. Dysregulated expression of miR-140 and miR-122 compromised microglial chemotaxis and led to reduced restriction of AD pathology. J Neuroinflammation 2024; 21:167. [PMID: 38956605 PMCID: PMC11218311 DOI: 10.1186/s12974-024-03162-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2024] [Accepted: 06/26/2024] [Indexed: 07/04/2024] Open
Abstract
BACKGROUND Deposition of amyloid β, which is produced by amyloidogenic cleavage of APP by β- and γ-secretase, is one of the primary hallmarks of AD pathology. APP can also be processed by α- and γ-secretase sequentially, to generate sAPPα, which has been shown to be neuroprotective by promoting neurite outgrowth and neuronal survival, etc. METHODS: The global expression profiles of miRNA in blood plasma samples taken from 11 AD patients as well as from 14 age and sex matched cognitively normal volunteers were analyzed using miRNA-seq. Then, overexpressed miR-140 and miR-122 both in vivo and in vitro, and knock-down of the endogenous expression of miR-140 and miR-122 in vitro. Used a combination of techniques, including molecular biology, immunohistochemistry, to detect the impact of miRNAs on AD pathology. RESULTS In this study, we identified that two miRNAs, miR-140-3p and miR-122-5p, both targeting ADAM10, the main α-secretase in CNS, were upregulated in the blood plasma of AD patients. Overexpression of these two miRNAs in mouse brains induced cognitive decline in wild type C57BL/6J mice as well as exacerbated dyscognition in APP/PS1 mice. Although significant changes in APP and total Aβ were not detected, significantly downregulated ADAM10 and its non-amyloidogenic product, sAPPα, were observed in the mouse brains overexpressing miR-140/miR-122. Immunohistology analysis revealed increased neurite dystrophy that correlated with the reduced microglial chemotaxis in the hippocampi of these mice, independent of the other two ADAM10 substrates (neuronal CX3CL1 and microglial TREM2) that were involved in regulating the microglial immunoactivity. Further in vitro analysis demonstrated that both the reduced neuritic outgrowth of mouse embryonic neuronal cells overexpressing miR-140/miR-122 and the reduced Aβ phagocytosis in microglia cells co-cultured with HT22 cells overexpressing miR-140/miR-122 could be rescued by overexpressing the specific inhibitory sequence of miR-140/miR-122 TuD as well as by addition of sAPPα, rendering these miRNAs as potential therapeutic targets. CONCLUSIONS Our results suggested that neuroprotective sAPPα was a key player in the neuropathological progression induced by dysregulated expression of miR-140 and miR-122. Targeting these miRNAs might serve as a promising therapeutic strategy in AD treatment.
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Affiliation(s)
- Chao Song
- School of Life Science and Technology, Jinan University, Guangzhou, Guangdong, 510632, China
| | - Shufang Li
- School of Life Science and Technology, Jinan University, Guangzhou, Guangdong, 510632, China
| | - Yingren Mai
- Department of Neurology, Institute of Neuroscience, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, The Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, Guangdong, 510260, China
| | - Linpeng Li
- School of Life Science and Technology, Jinan University, Guangzhou, Guangdong, 510632, China
| | - Guoku Dai
- School of Life Science and Technology, Jinan University, Guangzhou, Guangdong, 510632, China
| | - Yuan Zhou
- School of Life Science and Technology, Jinan University, Guangzhou, Guangdong, 510632, China
| | - Xiaosheng Liang
- School of Life Science and Technology, Jinan University, Guangzhou, Guangdong, 510632, China
- Guangdong-Hongkong-Macau Institute of CNS Regeneration, Ministry of Education CNS Regeneration Collaborative Joint Laboratory, Jinan University, Guangzhou, Guangdong, 510632, China
| | - Olivia Meilan Zou
- School of Life Science and Technology, Jinan University, Guangzhou, Guangdong, 510632, China
| | - Ya Wang
- School of Life Science and Technology, Jinan University, Guangzhou, Guangdong, 510632, China
| | - Libing Zhou
- Guangdong-Hongkong-Macau Institute of CNS Regeneration, Ministry of Education CNS Regeneration Collaborative Joint Laboratory, Jinan University, Guangzhou, Guangdong, 510632, China.
| | - Jun Liu
- Department of Neurology, Institute of Neuroscience, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, The Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, Guangdong, 510260, China.
| | - Yi Zou
- School of Life Science and Technology, Jinan University, Guangzhou, Guangdong, 510632, China.
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2
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Zhang J, Pandey M, Awe A, Lue N, Kittock C, Fikse E, Degner K, Staples J, Mokhasi N, Chen W, Yang Y, Adikaram P, Jacob N, Greenfest-Allen E, Thomas R, Bomeny L, Zhang Y, Petros TJ, Wang X, Li Y, Simonds WF. The association of GNB5 with Alzheimer disease revealed by genomic analysis restricted to variants impacting gene function. Am J Hum Genet 2024; 111:473-486. [PMID: 38354736 PMCID: PMC10940018 DOI: 10.1016/j.ajhg.2024.01.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 01/09/2024] [Accepted: 01/10/2024] [Indexed: 02/16/2024] Open
Abstract
Disease-associated variants identified from genome-wide association studies (GWASs) frequently map to non-coding areas of the genome such as introns and intergenic regions. An exclusive reliance on gene-agnostic methods of genomic investigation could limit the identification of relevant genes associated with polygenic diseases such as Alzheimer disease (AD). To overcome such potential restriction, we developed a gene-constrained analytical method that considers only moderate- and high-risk variants that affect gene coding sequences. We report here the application of this approach to publicly available datasets containing 181,388 individuals without and with AD and the resulting identification of 660 genes potentially linked to the higher AD prevalence among Africans/African Americans. By integration with transcriptome analysis of 23 brain regions from 2,728 AD case-control samples, we concentrated on nine genes that potentially enhance the risk of AD: AACS, GNB5, GNS, HIPK3, MED13, SHC2, SLC22A5, VPS35, and ZNF398. GNB5, the fifth member of the heterotrimeric G protein beta family encoding Gβ5, is primarily expressed in neurons and is essential for normal neuronal development in mouse brain. Homozygous or compound heterozygous loss of function of GNB5 in humans has previously been associated with a syndrome of developmental delay, cognitive impairment, and cardiac arrhythmia. In validation experiments, we confirmed that Gnb5 heterozygosity enhanced the formation of both amyloid plaques and neurofibrillary tangles in the brains of AD model mice. These results suggest that gene-constrained analysis can complement the power of GWASs in the identification of AD-associated genes and may be more broadly applicable to other polygenic diseases.
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Affiliation(s)
- Jianhua Zhang
- Metabolic Diseases Branch, Bldg. 10/Rm 8C-101, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Mritunjay Pandey
- Metabolic Diseases Branch, Bldg. 10/Rm 8C-101, National Institutes of Health, Bethesda, MD 20892, USA
| | - Adam Awe
- Metabolic Diseases Branch, Bldg. 10/Rm 8C-101, National Institutes of Health, Bethesda, MD 20892, USA
| | - Nicole Lue
- Metabolic Diseases Branch, Bldg. 10/Rm 8C-101, National Institutes of Health, Bethesda, MD 20892, USA
| | - Claire Kittock
- Metabolic Diseases Branch, Bldg. 10/Rm 8C-101, National Institutes of Health, Bethesda, MD 20892, USA
| | - Emma Fikse
- Metabolic Diseases Branch, Bldg. 10/Rm 8C-101, National Institutes of Health, Bethesda, MD 20892, USA
| | - Katherine Degner
- Metabolic Diseases Branch, Bldg. 10/Rm 8C-101, National Institutes of Health, Bethesda, MD 20892, USA
| | - Jenna Staples
- Metabolic Diseases Branch, Bldg. 10/Rm 8C-101, National Institutes of Health, Bethesda, MD 20892, USA
| | - Neha Mokhasi
- Metabolic Diseases Branch, Bldg. 10/Rm 8C-101, National Institutes of Health, Bethesda, MD 20892, USA
| | - Weiping Chen
- Genomic Core, National Institute of Diabetes and Digestive and Kidney Diseases, Bldg. 8/Rm 1A11, National Institutes of Health, Bethesda, MD 20892, USA
| | - Yanqin Yang
- Laboratory of Transplantation Genomics, National Heart Lung and Blood Institute, Bldg. 10/Rm 7S261, National Institutes of Health, Bethesda, MD 20892, USA
| | - Poorni Adikaram
- Metabolic Diseases Branch, Bldg. 10/Rm 8C-101, National Institutes of Health, Bethesda, MD 20892, USA
| | - Nirmal Jacob
- Metabolic Diseases Branch, Bldg. 10/Rm 8C-101, National Institutes of Health, Bethesda, MD 20892, USA
| | - Emily Greenfest-Allen
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Rachel Thomas
- Metabolic Diseases Branch, Bldg. 10/Rm 8C-101, National Institutes of Health, Bethesda, MD 20892, USA
| | - Laura Bomeny
- Metabolic Diseases Branch, Bldg. 10/Rm 8C-101, National Institutes of Health, Bethesda, MD 20892, USA
| | - Yajun Zhang
- Unit on Cellular and Molecular Neurodevelopment, Bldg. 35/Rm 3B 1002, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Timothy J Petros
- Unit on Cellular and Molecular Neurodevelopment, Bldg. 35/Rm 3B 1002, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Xiaowen Wang
- Partek Incorporated, 12747 Olive Boulevard, St. Louis, MO 63141, USA
| | - Yulong Li
- Metabolic Diseases Branch, Bldg. 10/Rm 8C-101, National Institutes of Health, Bethesda, MD 20892, USA
| | - William F Simonds
- Metabolic Diseases Branch, Bldg. 10/Rm 8C-101, National Institutes of Health, Bethesda, MD 20892, USA.
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3
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Peralta Cuasolo YM, Dupraz S, Unsain N, Bisbal M, Quassollo G, Galiano MR, Grassi D, Quiroga S, Sosa LJ. The GTPase Rab21 is required for neuronal development and migration in the cerebral cortex. J Neurochem 2023; 166:790-808. [PMID: 37534523 DOI: 10.1111/jnc.15925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 07/04/2023] [Accepted: 07/12/2023] [Indexed: 08/04/2023]
Abstract
Development of the mammalian neocortex requires proper inside-out migration of developing cortical neurons from the germinal ventricular zone toward the cortical plate. The mechanics of this migration requires precise coordination of different cellular phenomena including cytoskeleton dynamics, membrane trafficking, and cell adhesion. The small GTPases play a central role in all these events. The small GTPase Rab21 regulates migration and neurite growth in developing neurons. Moreover, regulators and effectors of Rab21 have been implicated in brain pathologies with cortical malformations, suggesting a key function for the Rab21 signaling pathway in cortical development. Mechanistically, it has been posited that Rab21 influences cell migration by controlling the trafficking of endocytic vesicles containing adhesion molecules. However, direct evidence of the participation of Rab21 or its mechanism of action in the regulation of cortical migration is still incomplete. In this study, we demonstrate that Rab21 plays a critical role in the differentiation and migration of pyramidal neurons by regulating the levels of the amyloid precursor protein on the neuronal cell surface. Rab21 loss of function increased the levels of membrane-exposed APP, resulting in impaired cortical neuronal differentiation and migration. These findings further our understanding of the processes governing the development of the cerebral cortex and shed light onto the molecular mechanisms behind cortical development disorders derived from the malfunctioning of Rab21 signaling effectors.
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Affiliation(s)
- Yael Macarena Peralta Cuasolo
- Departamento de Química Biológica Ranwell Caputto, Facultad de Ciencias Químicas, CIQUIBIC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Sebastián Dupraz
- Axonal Growth and Regeneration, German Center for Neurodegenarative Diseases, Bonn, Germany
| | - Nicolas Unsain
- Instituto de Investigación Médica Mercedes y Martín Ferreyra (INIMEC), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Córdoba, Córdoba, Argentina
- Centro de Biología Celular y Molecular (CeBiCeM, FCEFyN-UNC), Facultad de Ciencias Exactas Físicas y Naturales, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Mariano Bisbal
- Instituto de Investigación Médica Mercedes y Martín Ferreyra (INIMEC), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Córdoba, Córdoba, Argentina
- Instituto Universitario Ciencias Biomédicas de Córdoba (IUCBC), Córdoba, Argentina
| | - Gonzalo Quassollo
- Instituto de Investigación Médica Mercedes y Martín Ferreyra (INIMEC), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Mauricio R Galiano
- Departamento de Química Biológica Ranwell Caputto, Facultad de Ciencias Químicas, CIQUIBIC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Diego Grassi
- Departamento de Química Biológica Ranwell Caputto, Facultad de Ciencias Químicas, CIQUIBIC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Santiago Quiroga
- Departamento de Química Biológica Ranwell Caputto, Facultad de Ciencias Químicas, CIQUIBIC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Lucas Javier Sosa
- Departamento de Química Biológica Ranwell Caputto, Facultad de Ciencias Químicas, CIQUIBIC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
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4
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Baltissen D, Bold CS, Rehra L, Banićević M, Fricke J, Just J, Ludewig S, Buchholz CJ, Korte M, Müller UC. APPsα rescues CDK5 and GSK3β dysregulation and restores normal spine density in Tau transgenic mice. Front Cell Neurosci 2023; 17:1106176. [PMID: 36779015 PMCID: PMC9909437 DOI: 10.3389/fncel.2023.1106176] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Accepted: 01/02/2023] [Indexed: 01/27/2023] Open
Abstract
The Tau protein can be phosphorylated by numerous kinases. In Alzheimer's disease (AD) hyperphosphorylated Tau species accumulate as neurofibrillary tangles that constitute a major hallmark of AD. AD is further characterized by extracellular Aβ plaques, derived from the β-amyloid precursor protein APP. Whereas Aβ is produced by amyloidogenic APP processing, APP processing along the competing non-amyloidogenic pathway results in the secretion of neurotrophic and synaptotrophic APPsα. Recently, we demonstrated that APPsα has therapeutic effects in transgenic AD model mice and rescues Aβ-dependent impairments. Here, we examined the potential of APPsα to regulate two major Tau kinases, GSK3β and CDK5 in THY-Tau22 mice, a widely used mouse model of tauopathy. Immunohistochemistry revealed a dramatic increase in pathologically phosphorylated (AT8 and AT180) or misfolded Tau species (MC1) in the hippocampus of THY-Tau22 mice between 3 and 12 months of age. Using a highly sensitive radioactive kinase assay with recombinant human Tau as a substrate and immunoblotting, we demonstrate an increase in GSK3β and CDK5 activity in the hippocampus of THY-Tau22 mice. Interestingly, AAV-mediated intracranial expression of APPsα in THY-Tau22 mice efficiently restored normal GSK3β and CDK5 activity. Western blot analysis revealed upregulation of the CDK5 regulatory proteins p35 and p25, indicating CDK5 hyperactivation in THY-Tau22 mice. Strikingly, AAV-APPsα rescued p25 upregulation to wild-type levels even at stages of advanced Tau pathology. Sarkosyl fractionation used to study the abundance of soluble and insoluble phospho-Tau species revealed increased soluble AT8-Tau and decreased insoluble AT100-Tau species upon AAV-APPsα injection. Moreover, AAV-APPsα reduced misfolded (MC1) Tau species, particularly in somatodendritic compartments of CA1 pyramidal neurons. Finally, we show that AAV-APPsα upregulated PSD95 expression and rescued deficits in spine density of THY-Tau22 mice. Together our findings suggest that APPsα holds therapeutic potential to mitigate Tau-induced pathology.
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Affiliation(s)
- Danny Baltissen
- Department of Functional Genomics, Institute of Pharmacy and Molecular Biotechnology, Heidelberg University, Heidelberg, Germany
| | - Charlotte S. Bold
- Department of Functional Genomics, Institute of Pharmacy and Molecular Biotechnology, Heidelberg University, Heidelberg, Germany
| | - Lena Rehra
- Department of Functional Genomics, Institute of Pharmacy and Molecular Biotechnology, Heidelberg University, Heidelberg, Germany
| | - Marija Banićević
- Department of Functional Genomics, Institute of Pharmacy and Molecular Biotechnology, Heidelberg University, Heidelberg, Germany
| | - Justus Fricke
- Department of Functional Genomics, Institute of Pharmacy and Molecular Biotechnology, Heidelberg University, Heidelberg, Germany
| | - Jennifer Just
- Department of Cellular Neurobiology, Zoological Institute, Technical University of Braunschweig, Braunschweig, Germany
| | - Susann Ludewig
- Department of Cellular Neurobiology, Zoological Institute, Technical University of Braunschweig, Braunschweig, Germany
| | - Christian J. Buchholz
- Department of Molecular Biotechnology and Gene Therapy, Paul-Ehrlich-Institut, Langen, Germany
| | - Martin Korte
- Department of Cellular Neurobiology, Zoological Institute, Technical University of Braunschweig, Braunschweig, Germany,Helmholtz Centre for Infection Research, Neuroinflammation and Neurodegeneration Group, Braunschweig, Germany
| | - Ulrike C. Müller
- Department of Functional Genomics, Institute of Pharmacy and Molecular Biotechnology, Heidelberg University, Heidelberg, Germany,*Correspondence: Ulrike C. Müller,
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5
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Nahalka J. 1-L Transcription in Alzheimer's Disease. Curr Issues Mol Biol 2022; 44:3533-3551. [PMID: 36005139 PMCID: PMC9406503 DOI: 10.3390/cimb44080243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 08/04/2022] [Accepted: 08/06/2022] [Indexed: 11/23/2022] Open
Abstract
Alzheimer's disease is a very complex disease and better explanations and models are needed to understand how neurons are affected and microglia are activated. A new model of Alzheimer's disease is presented here, the β-amyloid peptide is considered an important RNA recognition/binding peptide. 1-L transcription revealed compatible sequences with AAUAAA (PAS signal) and UUUC (class III ARE rich in U) in the Aβ peptide, supporting the peptide-RNA regulatory model. When a hypothetical model of fibril selection with the prionic character of amyloid assemblies is added to the peptide-RNA regulatory model, the downregulation of the PI3K-Akt pathway and the upregulation of the PLC-IP3 pathway are well explained. The model explains why neurons are less protected from inflammation and why microglia are activated; why mitochondria are destabilized; why the autophagic flux is destabilized; and why the post-transcriptional attenuation of the axonal signal "noise" is interrupted. For example, the model suggests that Aβ peptide may post-transcriptionally control ELAVL2 (ELAV-like RNA binding protein 2) and DCP2 (decapping mRNA protein 2), which are known to regulate RNA processing, transport, and stability.
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Affiliation(s)
- Jozef Nahalka
- Institute of Chemistry, Centre for Glycomics, Slovak Academy of Sciences, Dubravska Cesta 9, SK-84538 Bratislava, Slovakia;
- Institute of Chemistry, Centre of Excellence for White-Green Biotechnology, Slovak Academy of Sciences, Trieda Andreja Hlinku 2, SK-94976 Nitra, Slovakia
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6
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Antonino M, Marmo P, Freites CL, Quassollo GE, Sánchez MF, Lorenzo A, Bignante EA. Aβ Assemblies Promote Amyloidogenic Processing of APP and Intracellular Accumulation of Aβ42 Through Go/Gβγ Signaling. Front Cell Dev Biol 2022; 10:852738. [PMID: 35445022 PMCID: PMC9013780 DOI: 10.3389/fcell.2022.852738] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Accepted: 03/07/2022] [Indexed: 12/16/2022] Open
Abstract
Alzheimer’s disease (AD) is characterized by the deposition of aggregated species of amyloid beta (Aβ) in the brain, which leads to progressive cognitive deficits and dementia. Aβ is generated by the successive cleavage of the amyloid precursor protein (APP), first by β-site APP cleaving enzyme 1 (BACE1) and subsequently by the γ-secretase complex. Those conditions which enhace or reduce its clearance predispose to Aβ aggregation and the development of AD. In vitro studies have demonstrated that Aβ assemblies spark a feed-forward loop heightening Aβ production. However, the underlying mechanism remains unknown. Here, we show that oligomers and fibrils of Aβ enhance colocalization and physical interaction of APP and BACE1 in recycling endosomes of human neurons derived from induced pluripotent stem cells and other cell types, which leads to exacerbated amyloidogenic processing of APP and intracellular accumulation of Aβ42. In cells that are overexpressing the mutant forms of APP which are unable to bind Aβ or to activate Go protein, we have found that treatment with aggregated Aβ fails to increase colocalization of APP with BACE1 indicating that Aβ-APP/Go signaling is involved in this process. Moreover, inhibition of Gβγ subunit signaling with βARKct or gallein prevents Aβ-dependent interaction of APP and BACE1 in endosomes, β-processing of APP, and intracellular accumulation of Aβ42. Collectively, our findings uncover a signaling mechanism leading to a feed-forward loop of amyloidogenesis that might contribute to Aβ pathology in the early stages of AD and suggest that gallein could have therapeutic potential.
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Affiliation(s)
- Magdalena Antonino
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Paula Marmo
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Carlos Leandro Freites
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
| | | | | | - Alfredo Lorenzo
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
- *Correspondence: Elena Anahi Bignante, ; Alfredo Lorenzo,
| | - Elena Anahi Bignante
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
- Instituto Universitario de Ciencias Biomédicas de Córdoba (IUCBC), Córdoba, Argentina
- *Correspondence: Elena Anahi Bignante, ; Alfredo Lorenzo,
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Hermans SJ, Nero TL, Morton CJ, Gooi JH, Crespi GAN, Hancock NC, Gao C, Ishii K, Markulić J, Parker MW. Structural biology of cell surface receptors implicated in Alzheimer’s disease. Biophys Rev 2021; 14:233-255. [DOI: 10.1007/s12551-021-00903-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 11/02/2021] [Indexed: 02/06/2023] Open
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8
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Nutraceutical and Probiotic Approaches to Examine Molecular Interactions of the Amyloid Precursor Protein APP in Drosophila Models of Alzheimer's Disease. Int J Mol Sci 2021; 22:ijms22137022. [PMID: 34209883 PMCID: PMC8269328 DOI: 10.3390/ijms22137022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 06/24/2021] [Accepted: 06/24/2021] [Indexed: 12/12/2022] Open
Abstract
Studies using animal models have shed light into the molecular and cellular basis for the neuropathology observed in patients with Alzheimer’s disease (AD). In particular, the role of the amyloid precursor protein (APP) plays a crucial role in the formation of senile plaques and aging-dependent degeneration. Here, we focus our review on recent findings using the Drosophila AD model to expand our understanding of APP molecular function and interactions, including insights gained from the fly homolog APP-like (APPL). Finally, as there is still no cure for AD, we review some approaches that have shown promising results in ameliorating AD-associated phenotypes, with special attention on the use of nutraceuticals and their molecular effects, as well as interactions with the gut microbiome. Overall, the phenomena described here are of fundamental significance for understanding network development and degeneration. Given the highly conserved nature of fundamental signaling pathways, the insight gained from animal models such as Drosophila melanogaster will likely advance the understanding of the mammalian brain, and thus be relevant to human health.
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Structural Studies Providing Insights into Production and Conformational Behavior of Amyloid-β Peptide Associated with Alzheimer's Disease Development. MOLECULES (BASEL, SWITZERLAND) 2021; 26:molecules26102897. [PMID: 34068293 PMCID: PMC8153327 DOI: 10.3390/molecules26102897] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 05/06/2021] [Accepted: 05/11/2021] [Indexed: 12/18/2022]
Abstract
Alzheimer's disease is the most common type of neurodegenerative disease in the world. Genetic evidence strongly suggests that aberrant generation, aggregation, and/or clearance of neurotoxic amyloid-β peptides (Aβ) triggers the disease. Aβ accumulates at the points of contact of neurons in ordered cords and fibrils, forming the so-called senile plaques. Aβ isoforms of different lengths are found in healthy human brains regardless of age and appear to play a role in signaling pathways in the brain and to have neuroprotective properties at low concentrations. In recent years, different substances have been developed targeting Aβ production, aggregation, interaction with other molecules, and clearance, including peptide-based drugs. Aβ is a product of sequential cleavage of the membrane glycoprotein APP (amyloid precursor protein) by β- and γ-secretases. A number of familial mutations causing an early onset of the disease have been identified in the APP, especially in its transmembrane domain. The mutations are reported to influence the production, oligomerization, and conformational behavior of Aβ peptides. This review highlights the results of structural studies of the main proteins involved in Alzheimer's disease pathogenesis and the molecular mechanisms by which perspective therapeutic substances can affect Aβ production and nucleation.
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10
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Lanchec E, Désilets A, Béliveau F, Fontaine-Carbonneau C, Laniel A, Leduc R, Lavoie C. Matriptase processing of APLP1 ectodomain alters its homodimerization. Sci Rep 2020; 10:10091. [PMID: 32572095 PMCID: PMC7308337 DOI: 10.1038/s41598-020-67005-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 05/29/2020] [Indexed: 11/09/2022] Open
Abstract
The amyloid beta peptide (Aβ) is derived from the amyloid precursor protein (APP) by secretase processing. APP is also cleaved by numerous other proteases, such as the type II transmembrane serine protease matriptase, with consequences on the production of Aβ. Because the APP homolog protein amyloid-like protein 1 (APLP1) shares similarities with APP, we sought to determine if matriptase also plays a role in its processing. Here, we demonstrate that matriptase directly interacts with APLP1 and that APLP1 is cleaved in cellulo by matriptase in its E1 ectodomains at arginine 124. Replacing Arg124 with Ala abolished APLP1 processing by matriptase. Using a bioluminescence resonance energy transfer (BRET) assay we found that matriptase reduces APLP1 homodimeric interactions. This study identifies matriptase as the first protease cleaving APLP1 in its dimerization domain, potentially altering the multiple functions associated with dimer formation.
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Affiliation(s)
- Erwan Lanchec
- Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, J1H5N4, Canada
| | - Antoine Désilets
- Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, J1H5N4, Canada
| | - François Béliveau
- Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, J1H5N4, Canada
| | - Cloé Fontaine-Carbonneau
- Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, J1H5N4, Canada
| | - Andréanne Laniel
- Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, J1H5N4, Canada
| | - Richard Leduc
- Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, J1H5N4, Canada.
| | - Christine Lavoie
- Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, J1H5N4, Canada.
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11
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Gabrych DR, Lau VZ, Niwa S, Silverman MA. Going Too Far Is the Same as Falling Short †: Kinesin-3 Family Members in Hereditary Spastic Paraplegia. Front Cell Neurosci 2019; 13:419. [PMID: 31616253 PMCID: PMC6775250 DOI: 10.3389/fncel.2019.00419] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 09/02/2019] [Indexed: 01/18/2023] Open
Abstract
Proper intracellular trafficking is essential for neuronal development and function, and when any aspect of this process is dysregulated, the resulting "transportopathy" causes neurological disorders. Hereditary spastic paraplegias (HSPs) are a family of such diseases attributed to over 80 spastic gait genes (SPG), specifically characterized by lower extremity spasticity and weakness. Multiple genes in the trafficking pathway such as those relating to microtubule structure and function and organelle biogenesis are representative disease loci. Microtubule motor proteins, or kinesins, are also causal in HSP, specifically mutations in Kinesin-I/KIF5A (SPG10) and two kinesin-3 family members; KIF1A (SPG30) and KIF1C (SPG58). KIF1A is a motor enriched in neurons, and involved in the anterograde transport of a variety of vesicles that contribute to pre- and post-synaptic assembly, autophagic processes, and neuron survival. KIF1C is ubiquitously expressed and, in addition to anterograde cargo transport, also functions in retrograde transport between the Golgi and the endoplasmic reticulum. Only a handful of KIF1C cargos have been identified; however, many have crucial roles such as neuronal differentiation, outgrowth, plasticity and survival. HSP-related kinesin-3 mutants are characterized mainly as loss-of-function resulting in deficits in motility, regulation, and cargo binding. Gain-of-function mutants are also seen, and are characterized by increased microtubule-on rates and hypermotility. Both sets of mutations ultimately result in misdelivery of critical cargos within the neuron. This likely leads to deleterious cell biological cascades that likely underlie or contribute to HSP clinical pathology and ultimately, symptomology. Due to the paucity of histopathological or cell biological data assessing perturbations in cargo localization, it has been difficult to positively link these mutations to the outcomes seen in HSPs. Ultimately, the goal of this review is to encourage future academic and clinical efforts to focus on "transportopathies" through a cargo-centric lens.
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Affiliation(s)
- Dominik R Gabrych
- Department of Biological Sciences, Simon Fraser University, Burnaby, BC, Canada
| | - Victor Z Lau
- Department of Biological Sciences, Simon Fraser University, Burnaby, BC, Canada
| | - Shinsuke Niwa
- Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Sendai, Japan
| | - Michael A Silverman
- Department of Biological Sciences, Simon Fraser University, Burnaby, BC, Canada.,Centre for Cell Biology, Development, and Disease, Simon Fraser University, Burnaby, BC, Canada
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12
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A Novel Apolipoprotein E Antagonist Functionally Blocks Apolipoprotein E Interaction With N-terminal Amyloid Precursor Protein, Reduces β-Amyloid-Associated Pathology, and Improves Cognition. Biol Psychiatry 2019; 86:208-220. [PMID: 31208706 PMCID: PMC6642011 DOI: 10.1016/j.biopsych.2019.04.026] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 03/21/2019] [Accepted: 04/15/2019] [Indexed: 12/28/2022]
Abstract
BACKGROUND The ɛ4 isoform of apolipoprotein E (apoE4) is a major genetic risk factor for the development of sporadic Alzheimer's disease (AD), and its modification has been an intense focus for treatment of AD during recent years. METHODS We investigated the binding of apoE, a peptide corresponding to its low-density lipoprotein receptor binding domain (amino acids 133-152; ApoEp), and modified ApoEp to amyloid precursor protein (APP) and their effects on amyloid-β (Aβ) production in cultured cells. Having discovered a peptide (6KApoEp) that blocks the interaction of apoE with N-terminal APP, we investigated the effects of this peptide and ApoEp on AD-like pathology and behavioral impairment in 3XTg-AD and 5XFAD transgenic mice. RESULTS ApoE and ApoEp, but not truncated apoE lacking the low-density lipoprotein receptor binding domain, physically interacted with N-terminal APP and thereby mediated Aβ production. Interestingly, the addition of 6 lysine residues to the N-terminus of ApoEp (6KApoEp) directly inhibited apoE binding to N-terminal APP and markedly limited apoE- and ApoEp-mediated Aβ generation, presumably through decreasing APP cellular membrane trafficking and p44/42 mitogen-activated protein kinase phosphorylation. Moreover, while promoting apoE interaction with APP by ApoEp exacerbated Aβ and tau brain pathologies in 3XTg-AD mice, disrupting this interaction by 6KApoEp ameliorated cerebral Aβ and tau pathologies, neuronal apoptosis, synaptic loss, and hippocampal-dependent learning and memory impairment in 5XFAD mice without altering cholesterol, low-density lipoprotein receptor, and apoE expression levels. CONCLUSIONS These data suggest that disrupting apoE interaction with N-terminal APP may be a novel disease-modifying therapeutic strategy for AD.
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13
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Novel role of APP cleavage by ADAM10 for breast cancer metastasis. EBioMedicine 2018; 38:5-6. [PMID: 30503863 PMCID: PMC6306391 DOI: 10.1016/j.ebiom.2018.11.050] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Accepted: 11/23/2018] [Indexed: 01/31/2023] Open
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14
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Mondragón-Rodríguez S, Gu N, Manseau F, Williams S. Alzheimer's Transgenic Model Is Characterized by Very Early Brain Network Alterations and β-CTF Fragment Accumulation: Reversal by β-Secretase Inhibition. Front Cell Neurosci 2018; 12:121. [PMID: 29867356 PMCID: PMC5952042 DOI: 10.3389/fncel.2018.00121] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Accepted: 04/13/2018] [Indexed: 11/29/2022] Open
Abstract
Alzheimer's disease (AD) is defined by the presence of amyloid-β (Aβ) and tau protein aggregates. However, increasing data is suggesting that brain network alterations rather than protein deposition could account for the early pathogenesis of the disease. In the present study, we performed in vitro extracellular field recordings in the CA1/subiculum area of the hippocampus from 30 days old J20-TG-AD mice. Here, we found that theta oscillations were significantly less rhythmic than those recorded from control group. In addition, J20 mice displayed significantly less theta-gamma cross-frequency coupling (CFC) as peak modulation indexes for slow (25-45 Hz) and fast (150-250 Hz) gamma frequency oscillations were reduced. Because inhibitory parvalbumin (PV) cells play a vital role in coordinating hippocampal theta and gamma oscillations, whole-cell patch-clamp recordings and extracellular stimulation were performed to access their intrinsic and synaptic properties. Whereas neither the inhibitory output of local interneurons to pyramidal cells (PCs) (inhibitory→PC) nor the excitatory output of PCs to PV cells (PC→PV) differed between control and J20 animals, the intrinsic excitability of PV cells was reduced in J20 mice compared to controls. Interestingly, optogenetic activation of PV interneurons which can directly drive theta oscillations in the hippocampus, did not rescue CFC impairments, suggesting the latter did not simply result from alteration of the underlying theta rhythm. Altered young J20 mice was characterized by the presence of β-CTF, but not with Aβ accumulation, in the hippocampus. Importantly, the β secretase inhibitor AZD3839-AstraZeneca significantly rescued the abnormal early electrophysiological phenotype of J20 mice. In conclusion, our data show that brain network alterations precede the canonical Aβ protein deposition and that, such alterations can be related to β-CTF fragment.
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Affiliation(s)
- Siddhartha Mondragón-Rodríguez
- Department of Psychiatry, Douglas Mental Health University Institute, McGill University, Montreal, QC, Canada
- CONACYT National Council for Science and Technology, Mexico City, Mexico
- UNAM Developmental Neurobiology and Neurophysiology, Institute of Neurobiology, National Autonomous University of Mexico, Querétaro, Mexico
| | - Ning Gu
- Department of Psychiatry, Douglas Mental Health University Institute, McGill University, Montreal, QC, Canada
- Department of Translational Neuroscience, The Royal Mental Health Research Institute, University of Ottawa, Ottawa, ON, Canada
| | - Frederic Manseau
- Department of Psychiatry, Douglas Mental Health University Institute, McGill University, Montreal, QC, Canada
| | - Sylvain Williams
- Department of Psychiatry, Douglas Mental Health University Institute, McGill University, Montreal, QC, Canada
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15
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Bignante EA, Ponce NE, Heredia F, Musso J, Krawczyk MC, Millán J, Pigino GF, Inestrosa NC, Boccia MM, Lorenzo A. APP/Go protein Gβγ-complex signaling mediates Aβ degeneration and cognitive impairment in Alzheimer's disease models. Neurobiol Aging 2017; 64:44-57. [PMID: 29331876 DOI: 10.1016/j.neurobiolaging.2017.12.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Revised: 12/05/2017] [Accepted: 12/10/2017] [Indexed: 11/15/2022]
Abstract
Deposition of amyloid-β (Aβ), the proteolytic product of the amyloid precursor protein (APP), might cause neurodegeneration and cognitive decline in Alzheimer's disease (AD). However, the direct involvement of APP in the mechanism of Aβ-induced degeneration in AD remains on debate. Here, we analyzed the interaction of APP with heterotrimeric Go protein in primary hippocampal cultures and found that Aβ deposition dramatically enhanced APP-Go protein interaction in dystrophic neurites. APP overexpression rendered neurons vulnerable to Aβ toxicity by a mechanism that required Go-Gβγ complex signaling and p38-mitogen-activated protein kinase activation. Gallein, a selective pharmacological inhibitor of Gβγ complex, inhibited Aβ-induced dendritic and axonal dystrophy, abnormal tau phosphorylation, synaptic loss, and neuronal cell death in hippocampal neurons expressing endogenous protein levels. In the 3xTg-AD mice, intrahippocampal application of gallein reversed memory impairment associated with early Aβ pathology. Our data provide further evidence for the involvement of APP/Go protein in Aβ-induced degeneration and reveal that Gβγ complex is a signaling target potentially relevant for developing therapies for halting Aβ degeneration in AD.
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Affiliation(s)
- Elena Anahi Bignante
- Instituto de Investigación Médica "Mercedes y Martín Ferreyra", INIMEC-CONICET- Universidad Nacional de Córdoba, Córdoba, Argentina; Instituto Universitario de Ciencias Biomédicas de Córdoda (IUCBC), Argentina
| | - Nicolás Eric Ponce
- Instituto de Investigación Médica "Mercedes y Martín Ferreyra", INIMEC-CONICET- Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Florencia Heredia
- Instituto de Investigación Médica "Mercedes y Martín Ferreyra", INIMEC-CONICET- Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Juliana Musso
- Instituto de Investigación Médica "Mercedes y Martín Ferreyra", INIMEC-CONICET- Universidad Nacional de Córdoba, Córdoba, Argentina
| | - María C Krawczyk
- Laboratorio de Neurofarmacología de los Procesos de Memoria, Cátedra de Farmacología, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Julieta Millán
- Laboratorio de Neurofarmacología de los Procesos de Memoria, Cátedra de Farmacología, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Gustavo F Pigino
- Instituto de Investigación Médica "Mercedes y Martín Ferreyra", INIMEC-CONICET- Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Nibaldo C Inestrosa
- Centro de Envejecimiento y Regeneración (CARE), Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile; Centro de Excelencia en Biomedicina de Magallanes (CEBIMA), Punta Arenas, Chile
| | - Mariano M Boccia
- Laboratorio de Neurofarmacología de los Procesos de Memoria, Cátedra de Farmacología, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Alfredo Lorenzo
- Instituto de Investigación Médica "Mercedes y Martín Ferreyra", INIMEC-CONICET- Universidad Nacional de Córdoba, Córdoba, Argentina; Departamento de Farmacología, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina.
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16
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Sosa LJ, Cáceres A, Dupraz S, Oksdath M, Quiroga S, Lorenzo A. The physiological role of the amyloid precursor protein as an adhesion molecule in the developing nervous system. J Neurochem 2017; 143:11-29. [PMID: 28677143 DOI: 10.1111/jnc.14122] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Revised: 06/28/2017] [Accepted: 06/29/2017] [Indexed: 12/12/2022]
Abstract
The amyloid precursor protein (APP) is a type I transmembrane glycoprotein better known for its participation in the physiopathology of Alzheimer disease as the source of the beta amyloid fragment. However, the physiological functions of the full length protein and its proteolytic fragments have remained elusive. APP was first described as a cell-surface receptor; nevertheless, increasing evidence highlighted APP as a cell adhesion molecule. In this review, we will focus on the current knowledge of the physiological role of APP as a cell adhesion molecule and its involvement in key events of neuronal development, such as migration, neurite outgrowth, growth cone pathfinding, and synaptogenesis. Finally, since APP is over-expressed in Down syndrome individuals because of the extra copy of chromosome 21, in the last section of the review, we discuss the potential contribution of APP to the neuronal and synaptic defects described in this genetic condition. Read the Editorial Highlight for this article on page 9. Cover Image for this issue: doi. 10.1111/jnc.13817.
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Affiliation(s)
- Lucas J Sosa
- Departamento de Química Biológica Ranwell Caputto, Facultad de Ciencias Químicas, CIQUIBIC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Alfredo Cáceres
- Laboratorio Neurobiología, Instituto Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina.,Instituto Universitario Ciencias Biomédicas Córdoba, Córdoba, Argentina
| | - Sebastián Dupraz
- Axonal Growth and Regeneration, German Center for Neurodegenarative Diseases, Bonn, Germany
| | - Mariana Oksdath
- Departamento de Química Biológica Ranwell Caputto, Facultad de Ciencias Químicas, CIQUIBIC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Santiago Quiroga
- Departamento de Química Biológica Ranwell Caputto, Facultad de Ciencias Químicas, CIQUIBIC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Alfredo Lorenzo
- Laboratorio de Neuropatología Experimental, Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
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17
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Montagna E, Dorostkar MM, Herms J. The Role of APP in Structural Spine Plasticity. Front Mol Neurosci 2017; 10:136. [PMID: 28539872 PMCID: PMC5423954 DOI: 10.3389/fnmol.2017.00136] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Accepted: 04/21/2017] [Indexed: 11/15/2022] Open
Abstract
Amyloid precursor protein (APP) is a transmembrane protein highly expressed in neurons. The full-length protein has cell-adhesion and receptor-like properties, which play roles in synapse formation and stability. Furthermore, APP can be cleaved by several proteases into numerous fragments, many of which affect synaptic function and stability. This review article focuses on the mechanisms of APP in structural spine plasticity, which encompasses the morphological alterations at excitatory synapses. These occur as changes in the number and morphology of dendritic spines, which correspond to the postsynaptic compartment of excitatory synapses. Both overexpression and knockout (KO) of APP lead to impaired synaptic plasticity. Recent data also suggest a role of APP in the regulation of astrocytic D-serine homeostasis, which in turn regulates synaptic plasticity.
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Affiliation(s)
- Elena Montagna
- Department for Translational Brain Research, German Center for Neurodegenerative Diseases (DZNE), Ludwig-Maximilian-University MunichMunich, Germany
| | - Mario M Dorostkar
- Center for Neuropathology and Prion Research, Ludwig-Maximilian-University MunichMunich, Germany
| | - Jochen Herms
- Department for Translational Brain Research, German Center for Neurodegenerative Diseases (DZNE), Ludwig-Maximilian-University MunichMunich, Germany.,Center for Neuropathology and Prion Research, Ludwig-Maximilian-University MunichMunich, Germany.,Munich Cluster of Systems Neurology (SyNergy), Ludwig-Maximilian-University MunichMunich, Germany
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