1
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Chauhan P, Wadhwa K, Singh G, Gupta S, Iqbal D, Abomughaid MM, Almutary AG, Mishra PC, Nelson VK, Jha NK. Exploring complexities of Alzheimer's disease: New insights into molecular and cellular mechanisms of neurodegeneration and targeted therapeutic interventions. Ageing Res Rev 2024:102548. [PMID: 39419399 DOI: 10.1016/j.arr.2024.102548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Revised: 10/09/2024] [Accepted: 10/11/2024] [Indexed: 10/19/2024]
Abstract
Alzheimer's disease (AD), the common form of dementia globally, is a complex condition including neurodegeneration; shares incompletely known pathogenesis. Signal transduction and biological activities, including cell metabolism, growth, and death are regulated by different signaling pathways including AKT/MAPK, Wnt, Leptin, mTOR, ubiquitin, Sirt1, and insulin. Absolute evidence linking specific molecular pathways with the genesis and/or progression of AD is still lacking. Changes in gut microbiota and blood-brain barrier also cause amyloid β aggregation in AD. The current review reports significant characteristics of various signaling pathways, their relationship with each other, and how they interact in disease genesis and/or progression. Nevertheless, due to the enormous complexity of the brain and numerous chemical linkages between these pathways, the use of signaling pathways as possible targets for drug development against AD is minimal. Currently, there is no permanent cure for AD, and there is no way to stop brain cell loss. This review also aimed to draw attention to the role of a novel group of signaling pathways, which can be collectively dubbed "anti-AD pathways", in multi-target therapy for AD, where cellular metabolic functions are severely impaired. Thus, different hypotheses have been formulated and elaborated to explain the genesis of AD, which can be further explored for drug development too.
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Affiliation(s)
- Payal Chauhan
- Department of Pharmaceutical Sciences, Maharshi Dayanand University, Rohtak, Haryana, 124001, India
| | - Karan Wadhwa
- Department of Pharmaceutical Sciences, Maharshi Dayanand University, Rohtak, Haryana, 124001, India
| | - Govind Singh
- Department of Pharmaceutical Sciences, Maharshi Dayanand University, Rohtak, Haryana, 124001, India.
| | - Saurabh Gupta
- Deparment of Biotechnology, GLA University, Mathura, India
| | - Danish Iqbal
- Department of Health Information Management, College of Applied Medical Sciences, Buraydah Private Colleges, Buraydah 51418, Saudi Arabia
| | - Mosleh Mohammad Abomughaid
- Department of Medical Laboratory Sciences, College of Applied Medical Sciences, University of Bisha, Bisha, 61922, Saudi Arabia
| | - Abdulmajeed G Almutary
- Department of Biomedical Sciences, College of Health Sciences, Abu Dhabi University, Abu Dhabi P.O. Box 59911, United Arab Emirates
| | - Prabhu Chandra Mishra
- Department of Biotechnology, School of Engineering and Technology, Sharda University, Greater Noida, India
| | - Vinod Kumar Nelson
- Raghavendra Institute of Pharmaceutical Education and Research, Anantapur, India
| | - Niraj Kumar Jha
- Centre for Global Health Research, Saveetha Medical College, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, India; Centre of Research Impact and Outreach, Chitkara University Institute of Engineering and Technology, Chitkara University, Punjab, India; School of Bioengineering & Biosciences, Lovely Professional University, Phagwara 144411, India.
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2
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Sinha P, Turchyna Y, Mitchell SPC, Sadek M, Armagan G, Perrin F, Maesako M, Berezovska O. Glutamate Transporter 1 as a Novel Negative Regulator of Amyloid β. Cells 2024; 13:1600. [PMID: 39404364 PMCID: PMC11475981 DOI: 10.3390/cells13191600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2024] [Revised: 09/16/2024] [Accepted: 09/17/2024] [Indexed: 10/19/2024] Open
Abstract
Glutamate transporter-1 (GLT-1) dynamics are implicated in excitotoxicity and Alzheimer's disease (AD) progression. Early stages of AD are often marked by hyperactivity and increased epileptiform activity preceding cognitive decline. Previously, we identified a direct interaction between GLT-1 and Presenilin 1 (PS1) in the brain, highlighting GLT-1 as a promising target in AD research. This study reports the significance of this interaction and uncovers a novel role of GLT-1 in modulating amyloid-beta (Aβ) production. Overexpression of GLT-1 in cells reduces the levels of Aβ40 and Aβ42 by decreasing γ-secretase activity pertinent to APP processing and induces a more "open" PS1 conformation, resulting in decreased Aβ42/40 ratio. Inhibition of the GLT-1/PS1 interaction using cell-permeable peptides produced an opposing effect on Aβ, highlighting the pivotal role of this interaction in regulating Aβ levels. These findings emphasize the potential of targeting the GLT-1/PS1 interaction as a novel therapeutic strategy for AD.
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Affiliation(s)
| | | | | | | | | | | | | | - Oksana Berezovska
- Alzheimer Research Unit, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital, Harvard Medical School, 114, 16th Street, Charlestown, MA 02129, USA
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3
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Perrin F, Sinha P, Mitchell SPC, Sadek M, Maesako M, Berezovska O. Identification of PS1/gamma-secretase and glutamate transporter GLT-1 interaction sites. J Biol Chem 2024; 300:107172. [PMID: 38499151 PMCID: PMC11015137 DOI: 10.1016/j.jbc.2024.107172] [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: 09/23/2023] [Revised: 02/02/2024] [Accepted: 03/05/2024] [Indexed: 03/20/2024] Open
Abstract
The recently discovered interaction between Presenilin 1 (PS1), a catalytic subunit of γ-secretase responsible for generating amyloid-β peptides, and GLT-1, a major glutamate transporter in the brain (EAAT2), provides a mechanistic link between these two key factors involved in Alzheimer's disease (AD) pathology. Modulating this interaction can be crucial to understand the consequence of such crosstalk in AD context and beyond. However, the interaction sites between these two proteins are unknown. Herein, we utilized an alanine scanning approach coupled with FRET-based fluorescence lifetime imaging microscopy to identify the interaction sites between PS1 and GLT-1 in their native environment within intact cells. We found that GLT-1 residues at position 276 to 279 (TM5) and PS1 residues at position 249 to 252 (TM6) are crucial for GLT-1-PS1 interaction. These results have been cross validated using AlphaFold Multimer prediction. To further investigate whether this interaction of endogenously expressed GLT-1 and PS1 can be prevented in primary neurons, we designed PS1/GLT-1 cell-permeable peptides (CPPs) targeting the PS1 or GLT-1 binding site. We used HIV TAT domain to allow for cell penetration which was assayed in neurons. First, we assessed the toxicity and penetration of CPPs by confocal microscopy. Next, to ensure the efficiency of CPPs, we monitored the modulation of GLT-1-PS1 interaction in intact neurons by fluorescence lifetime imaging microscopy. We saw significantly less interaction between PS1 and GLT-1 with both CPPs. Our study establishes a new tool to study the functional aspect of GLT-1-PS1 interaction and its relevance in normal physiology and AD models.
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Affiliation(s)
- Florian Perrin
- MassGeneral Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
| | - Priyanka Sinha
- MassGeneral Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
| | - Shane Patrick Clancy Mitchell
- MassGeneral Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
| | - Michael Sadek
- MassGeneral Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
| | - Masato Maesako
- MassGeneral Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
| | - Oksana Berezovska
- MassGeneral Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA.
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4
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Wu C, Ruan T, Yuan Y, Xu C, Du L, Wang F, Xu S. Alterations in Synaptic Connectivity and Synaptic Transmission in Alzheimer's Disease with High Physical Activity. J Alzheimers Dis 2024; 99:1005-1022. [PMID: 38759013 DOI: 10.3233/jad-240123] [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] [Indexed: 05/19/2024]
Abstract
Background Alzheimer's disease (AD) is a progressive neurodegeneration disease. Physical activity is one of the most promising modifiable lifestyles that can be effective in slowing down the progression of AD at an early stage. Objective Explore the molecular processes impaired in AD that were conversely preserved and enhanced by physical activity. Methods Integrated transcriptomic analyses were performed in datasets that contain AD patients and elders with different degrees of physical activity. The changes of the hub genes were validated through analyzing another two datasets. The expression of the hub genes was further detected in the hippocampus and cortexes of APP/PS1 transgenic mice with or without physical activity by Quantitative polymerase chain reaction (qPCR). Results Cross-comparison highlighted 195 DEGs displaying opposed regulation patterns between AD and high physical activity (HPA). The common DEGs were predominantly involved in synaptic vesicle recycling and synaptic transmission, largely downregulated in AD patients but upregulated in the elders with HPA. Two key modules and four hub genes that were related to synaptic vesicle turnover were obtained from the PPI network. The expression of these hub genes (SYT1, SYT4, SH3GL2, and AP2M1) was significantly decreased in AD transgenic mice and was reversed by HPA training. Conclusions HPA may reverse AD pathology by upregulating a range of synaptic vesicle transport related proteins which might improve the efficiency of synaptic vesicle turnover and facilitate inter-neuronal information transfer. The study provides novel insights into the mechanisms underlining the protective effects of HPA on AD.
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Affiliation(s)
- Can Wu
- Department of Physiology and Pathophysiology, Health Science Center, Ningbo University, Ningbo, Zhejiang, China
| | - Tingting Ruan
- Department of Physiology and Pathophysiology, Health Science Center, Ningbo University, Ningbo, Zhejiang, China
| | - Yalan Yuan
- Department of Physiology and Pathophysiology, Health Science Center, Ningbo University, Ningbo, Zhejiang, China
| | - Chunshuang Xu
- Department of Physiology and Pathophysiology, Health Science Center, Ningbo University, Ningbo, Zhejiang, China
| | - Lijuan Du
- Department of Physiology and Pathophysiology, Health Science Center, Ningbo University, Ningbo, Zhejiang, China
- Faculty of Physical Education, Ningbo University, Ningbo, Zhejiang, China
| | - Fang Wang
- Department of Pharmacy, Zhejiang Pharmaceutical University, Ningbo, Zhejiang, China
| | - Shujun Xu
- Department of Physiology and Pathophysiology, Health Science Center, Ningbo University, Ningbo, Zhejiang, China
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5
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Perrin F, Sinha P, Mitchell S, Maesako M, Berezovska O. Identification of PS1/gamma-secretase and glutamate transporter GLT-1 interaction sites. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.30.542955. [PMID: 37398024 PMCID: PMC10312500 DOI: 10.1101/2023.05.30.542955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
The recently discovered interaction between Presenilin 1 (PS1), a catalytic subunit of γ-secretase responsible for generating amyloid-β (Aβ) peptides, and GLT-1, a major glutamate transporter in the brain (EAAT2) provides a mechanistic link between these two key factors involved in Alzheimer's disease (AD) pathology. Modulating this interaction can be crucial to understand the consequence of such crosstalk in AD context and beyond. However, the interaction sites between these two proteins are unknown. Herein, we utilized an alanine scanning approach coupled with FRET-based fluorescence lifetime imaging microscopy (FLIM) to identify the interaction sites between PS1 and GLT-1 in their native environment within intact cells. We found that GLT-1 residues at position 276 to 279 (TM5) and PS1 residues at position 249 to 252 (TM6) are crucial for GLT-1/PS1 interaction. These results have been cross validated using AlphaFold Multimer prediction. To further investigate whether this interaction of endogenously expressed GLT-1 and PS1 can be prevented in primary neurons, we designed PS1/GLT-1 cell-permeable peptides (CPPs) targeting the PS1 or GLT-1 binding site. We used HIV TAT domain to allow for cell penetration which was assayed in neurons. First, we assessed the toxicity and penetration of CPPs by confocal microscopy. Next, to ensure the efficiency of CPPs, we monitored the modulation of GLT-1/PS1 interaction in intact neurons by FLIM. We saw significantly less interaction between PS1 and GLT-1 with both CPPs. Our study establishes a new tool to study the functional aspect of GLT-1/PS1 interaction and its relevance in normal physiology and AD models.
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6
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Restrepo LJ, DePew AT, Moese ER, Tymanskyj SR, Parisi MJ, Aimino MA, Duhart JC, Fei H, Mosca TJ. γ-secretase promotes Drosophila postsynaptic development through the cleavage of a Wnt receptor. Dev Cell 2022; 57:1643-1660.e7. [PMID: 35654038 DOI: 10.1016/j.devcel.2022.05.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 04/06/2022] [Accepted: 05/10/2022] [Indexed: 12/27/2022]
Abstract
Developing synapses mature through the recruitment of specific proteins that stabilize presynaptic and postsynaptic structure and function. Wnt ligands signaling via Frizzled (Fz) receptors play many crucial roles in neuronal and synaptic development, but whether and how Wnt and Fz influence synaptic maturation is incompletely understood. Here, we show that Fz2 receptor cleavage via the γ-secretase complex is required for postsynaptic development and maturation. In the absence of γ-secretase, Drosophila neuromuscular synapses fail to recruit postsynaptic scaffolding and cytoskeletal proteins, leading to behavioral deficits. Introducing presenilin mutations linked to familial early-onset Alzheimer's disease into flies leads to synaptic maturation phenotypes that are identical to those seen in null alleles. This conserved role for γ-secretase in synaptic maturation and postsynaptic development highlights the importance of Fz2 cleavage and suggests that receptor processing by proteins linked to neurodegeneration may be a shared mechanism with aspects of synaptic development.
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Affiliation(s)
- Lucas J Restrepo
- Department of Neuroscience, Vickie and Jack Farber Institute of Neuroscience, Thomas Jefferson University, Bluemle Life Sciences Building, Philadelphia, PA 19107, USA
| | - Alison T DePew
- Department of Neuroscience, Vickie and Jack Farber Institute of Neuroscience, Thomas Jefferson University, Bluemle Life Sciences Building, Philadelphia, PA 19107, USA
| | - Elizabeth R Moese
- Department of Neuroscience, Vickie and Jack Farber Institute of Neuroscience, Thomas Jefferson University, Bluemle Life Sciences Building, Philadelphia, PA 19107, USA
| | - Stephen R Tymanskyj
- Department of Neuroscience, Vickie and Jack Farber Institute of Neuroscience, Thomas Jefferson University, Bluemle Life Sciences Building, Philadelphia, PA 19107, USA
| | - Michael J Parisi
- Department of Neuroscience, Vickie and Jack Farber Institute of Neuroscience, Thomas Jefferson University, Bluemle Life Sciences Building, Philadelphia, PA 19107, USA
| | - Michael A Aimino
- Department of Neuroscience, Vickie and Jack Farber Institute of Neuroscience, Thomas Jefferson University, Bluemle Life Sciences Building, Philadelphia, PA 19107, USA
| | - Juan Carlos Duhart
- Department of Neuroscience, Vickie and Jack Farber Institute of Neuroscience, Thomas Jefferson University, Bluemle Life Sciences Building, Philadelphia, PA 19107, USA
| | - Hong Fei
- Department of Neuroscience, Vickie and Jack Farber Institute of Neuroscience, Thomas Jefferson University, Bluemle Life Sciences Building, Philadelphia, PA 19107, USA
| | - Timothy J Mosca
- Department of Neuroscience, Vickie and Jack Farber Institute of Neuroscience, Thomas Jefferson University, Bluemle Life Sciences Building, Philadelphia, PA 19107, USA.
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7
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Louros N, Ramakers M, Michiels E, Konstantoulea K, Morelli C, Garcia T, Moonen N, D'Haeyer S, Goossens V, Thal DR, Audenaert D, Rousseau F, Schymkowitz J. Mapping the sequence specificity of heterotypic amyloid interactions enables the identification of aggregation modifiers. Nat Commun 2022; 13:1351. [PMID: 35292653 PMCID: PMC8924238 DOI: 10.1038/s41467-022-28955-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 02/11/2022] [Indexed: 02/07/2023] Open
Abstract
Heterotypic amyloid interactions between related protein sequences have been observed in functional and disease amyloids. While sequence homology seems to favour heterotypic amyloid interactions, we have no systematic understanding of the structural rules determining such interactions nor whether they inhibit or facilitate amyloid assembly. Using structure-based thermodynamic calculations and extensive experimental validation, we performed a comprehensive exploration of the defining role of sequence promiscuity in amyloid interactions. Using tau as a model system we demonstrate that proteins with local sequence homology to tau amyloid nucleating regions can modify fibril nucleation, morphology, assembly and spreading of aggregates in cultured cells. Depending on the type of mutation such interactions inhibit or promote aggregation in a manner that can be predicted from structure. We find that these heterotypic amyloid interactions can result in the subcellular mis-localisation of these proteins. Moreover, equilibrium studies indicate that the critical concentration of aggregation is altered by heterotypic interactions. Our findings suggest a structural mechanism by which the proteomic background can modulate the aggregation propensity of amyloidogenic proteins and we discuss how such sequence-specific proteostatic perturbations could contribute to the selective cellular susceptibility of amyloid disease progression. In this work, Louros et al. uncover a rule book for interactions of amyloids with other proteins. This grammar was shown to promote cellular spreading of tau aggregates in cells, but can also be harvested to develop structure-based aggregation blockers.
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Affiliation(s)
- Nikolaos Louros
- Switch Laboratory, VIB Center for Brain and Disease Research, Herestraat 49, 3000, Leuven, Belgium.,Switch Laboratory, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, 3000, Leuven, Belgium
| | - Meine Ramakers
- Switch Laboratory, VIB Center for Brain and Disease Research, Herestraat 49, 3000, Leuven, Belgium.,Switch Laboratory, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, 3000, Leuven, Belgium
| | - Emiel Michiels
- Switch Laboratory, VIB Center for Brain and Disease Research, Herestraat 49, 3000, Leuven, Belgium.,Switch Laboratory, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, 3000, Leuven, Belgium
| | - Katerina Konstantoulea
- Switch Laboratory, VIB Center for Brain and Disease Research, Herestraat 49, 3000, Leuven, Belgium.,Switch Laboratory, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, 3000, Leuven, Belgium
| | - Chiara Morelli
- Switch Laboratory, VIB Center for Brain and Disease Research, Herestraat 49, 3000, Leuven, Belgium.,Switch Laboratory, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, 3000, Leuven, Belgium
| | - Teresa Garcia
- Switch Laboratory, VIB Center for Brain and Disease Research, Herestraat 49, 3000, Leuven, Belgium.,Switch Laboratory, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, 3000, Leuven, Belgium
| | - Nele Moonen
- Switch Laboratory, VIB Center for Brain and Disease Research, Herestraat 49, 3000, Leuven, Belgium.,Switch Laboratory, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, 3000, Leuven, Belgium
| | - Sam D'Haeyer
- VIB Screening Core, Ghent, Belgium.,Centre for Bioassay Development and Screening (C-BIOS), Ghent University, Ghent, Belgium
| | - Vera Goossens
- VIB Screening Core, Ghent, Belgium.,Centre for Bioassay Development and Screening (C-BIOS), Ghent University, Ghent, Belgium
| | - Dietmar Rudolf Thal
- KU Leuven, Leuven Brain Institute, 3000, Leuven, Belgium.,Laboratory for Neuropathology, KU Leuven, and Department of Pathology, UZ Leuven, 3000, Leuven, Belgium
| | - Dominique Audenaert
- VIB Screening Core, Ghent, Belgium.,Centre for Bioassay Development and Screening (C-BIOS), Ghent University, Ghent, Belgium
| | - Frederic Rousseau
- Switch Laboratory, VIB Center for Brain and Disease Research, Herestraat 49, 3000, Leuven, Belgium. .,Switch Laboratory, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, 3000, Leuven, Belgium.
| | - Joost Schymkowitz
- Switch Laboratory, VIB Center for Brain and Disease Research, Herestraat 49, 3000, Leuven, Belgium. .,Switch Laboratory, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, 3000, Leuven, Belgium.
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CMOS Perceptron for Vesicle Fusion Classification. ELECTRONICS 2022. [DOI: 10.3390/electronics11060843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Edge computing (processing data close to its source) is one of the fastest developing areas of modern electronics and hardware information technology. This paper presents the implementation process of an analog CMOS preprocessor for use in a distributed environment for processing medical data close to the source. The task of the circuit is to analyze signals of vesicle fusion, which is the basis of life processes in multicellular organisms. The functionality of the preprocessor is based on a classifier of full and partial fusions. The preprocessor is dedicated to operate in amperometric systems, and the analyzed signals are data from carbon nanotube electrodes. The accuracy of the classifier is at the level of 93.67%. The implementation was performed in the 65 nm CMOS technology with a 0.3 V power supply. The circuit operates in the weak-inversion mode and is dedicated to be powered by thermal cells of the human energy harvesting class. The maximum power consumption of the circuit equals 416 nW, which makes it possible to use it as an implantable chip. The results can be used, among others, in the diagnosis of precancerous conditions.
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9
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Szczęsny S, Pietrzak P. Exocytotic vesicle fusion classification for early disease diagnosis using a mobile GPU microsystem. Neural Comput Appl 2022. [DOI: 10.1007/s00521-021-06676-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
AbstractThis work addresses monitoring vesicle fusions occurring during the exocytosis process, which is the main way of intercellular communication. Certain vesicle behaviors may also indicate certain precancerous conditions in cells. For this purpose we designed a system able to detect two main types of exocytosis: a full fusion and a kiss-and-run fusion, based on data from multiple amperometric sensors at once. It uses many instances of small perceptron neural networks in a massively parallel manner and runs on Jetson TX2 platform, which uses a GPU for parallel processing. Based on performed benchmarking, approximately 140,000 sensors can be processed in real time within the sensor sampling period equal to 10 ms and an accuracy of 99$$\%$$
%
. The work includes an analysis of the system performance with varying neural network sizes, input data sizes, and sampling periods of fusion signals.
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10
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Mohanraj N, Joshi NS, Poulose R, Patil RR, Santhoshkumar R, Kumar A, Waghmare GP, Saha AK, Haider SZ, Markandeya YS, Dey G, Rao LT, Govindaraj P, Mehta B. A proteomic study to unveil lead toxicity-induced memory impairments invoked by synaptic dysregulation. Toxicol Rep 2022; 9:1501-1513. [DOI: 10.1016/j.toxrep.2022.07.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 07/02/2022] [Accepted: 07/05/2022] [Indexed: 11/17/2022] Open
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11
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Haytural H, Benfeitas R, Schedin-Weiss S, Bereczki E, Rezeli M, Unwin RD, Wang X, Dammer EB, Johnson ECB, Seyfried NT, Winblad B, Tijms BM, Visser PJ, Frykman S, Tjernberg LO. Insights into the changes in the proteome of Alzheimer disease elucidated by a meta-analysis. Sci Data 2021; 8:312. [PMID: 34862388 PMCID: PMC8642431 DOI: 10.1038/s41597-021-01090-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 10/21/2021] [Indexed: 11/10/2022] Open
Abstract
Mass spectrometry (MS)-based proteomics is a powerful tool to explore pathogenic changes of a disease in an unbiased manner and has been used extensively in Alzheimer disease (AD) research. Here, by performing a meta-analysis of high-quality proteomic studies, we address which pathological changes are observed consistently and therefore most likely are of great importance for AD pathogenesis. We retrieved datasets, comprising a total of 21,588 distinct proteins identified across 857 postmortem human samples, from ten studies using labeled or label-free MS approaches. Our meta-analysis findings showed significant alterations of 757 and 1,195 proteins in AD in the labeled and label-free datasets, respectively. Only 33 proteins, some of which were associated with synaptic signaling, had the same directional change across the individual studies. However, despite alterations in individual proteins being different between the labeled and the label-free datasets, several pathways related to synaptic signaling, oxidative phosphorylation, immune response and extracellular matrix were commonly dysregulated in AD. These pathways represent robust changes in the human AD brain and warrant further investigation.
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Affiliation(s)
- Hazal Haytural
- Department of Neurobiology, Care Sciences and Society, Division of Neurogeriatrics, Center for Alzheimer Research, Karolinska Institutet, Solna, Sweden.
| | - Rui Benfeitas
- National Bioinformatics Infrastructure Sweden (NBIS), Science for Life Laboratory, Department of Biochemistry and Biophysics, Stockholm University, S-10691, Stockholm, Sweden
| | - Sophia Schedin-Weiss
- Department of Neurobiology, Care Sciences and Society, Division of Neurogeriatrics, Center for Alzheimer Research, Karolinska Institutet, Solna, Sweden
| | - Erika Bereczki
- Department of Neurobiology, Care Sciences and Society, Division of Neurogeriatrics, Center for Alzheimer Research, Karolinska Institutet, Solna, Sweden
| | - Melinda Rezeli
- Division of Clinical Protein Science & Imaging, Department of Clinical Sciences (Lund) and Department of Biomedical Engineering, Lund University, Lund, Sweden
| | - Richard D Unwin
- Stoller Biomarker Discovery Centre, and Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester Academic Health Sciences Centre, CityLabs 1.0, Nelson Street, Manchester, M13 9NQ, UK
| | - Xusheng Wang
- Department of Biology, University of North Dakota, Grand Forks, ND, USA
| | - Eric B Dammer
- Goizueta Alzheimer's Disease Research Center, Emory University School of Medicine, Atlanta, GA, USA
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA
| | - Erik C B Johnson
- Goizueta Alzheimer's Disease Research Center, Emory University School of Medicine, Atlanta, GA, USA
- Department of Neurology, Emory University School of Medicine, Atlanta, GA, USA
| | - Nicholas T Seyfried
- Goizueta Alzheimer's Disease Research Center, Emory University School of Medicine, Atlanta, GA, USA
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA
- Department of Neurology, Emory University School of Medicine, Atlanta, GA, USA
| | - Bengt Winblad
- Department of Neurobiology, Care Sciences and Society, Division of Neurogeriatrics, Center for Alzheimer Research, Karolinska Institutet, Solna, Sweden
- Karolinska University Hospital, Theme of Inflammation and Aging, Huddinge, Sweden
| | - Betty M Tijms
- Alzheimer Center Amsterdam, Department of Neurology, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, Amsterdam UMC, Amsterdam, The Netherlands
| | - Pieter Jelle Visser
- Department of Neurobiology, Care Sciences and Society, Division of Neurogeriatrics, Center for Alzheimer Research, Karolinska Institutet, Solna, Sweden
- Alzheimer Center Amsterdam, Department of Neurology, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, Amsterdam UMC, Amsterdam, The Netherlands
- Alzheimer Center Limburg, School for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands
| | - Susanne Frykman
- Department of Neurobiology, Care Sciences and Society, Division of Neurogeriatrics, Center for Alzheimer Research, Karolinska Institutet, Solna, Sweden
| | - Lars O Tjernberg
- Department of Neurobiology, Care Sciences and Society, Division of Neurogeriatrics, Center for Alzheimer Research, Karolinska Institutet, Solna, Sweden.
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12
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Jęśko H, Wieczorek I, Wencel PL, Gąssowska-Dobrowolska M, Lukiw WJ, Strosznajder RP. Age-Related Transcriptional Deregulation of Genes Coding Synaptic Proteins in Alzheimer's Disease Murine Model: Potential Neuroprotective Effect of Fingolimod. Front Mol Neurosci 2021; 14:660104. [PMID: 34305524 PMCID: PMC8299068 DOI: 10.3389/fnmol.2021.660104] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 05/31/2021] [Indexed: 12/11/2022] Open
Abstract
Alzheimer's disease (AD) induces time-dependent changes in sphingolipid metabolism, which may affect transcription regulation and neuronal phenotype. We, therefore, analyzed the influence of age, amyloid β precursor protein (AβPP), and the clinically approved, bioavailable sphingosine-1-phosphate receptor modulator fingolimod (FTY720) on the expression of synaptic proteins. RNA was isolated, reverse-transcribed, and subjected to real-time PCR. Expression of mutant (V717I) AβPP led to few changes at 3 months of age but reduced multiple mRNA coding for synaptic proteins in a 12-month-old mouse brain. Complexin 1 (Cplx1), SNAP25 (Snap25), syntaxin 1A (Stx1a), neurexin 1 (Nrxn1), neurofilament light (Nefl), and synaptotagmin 1 (Syt1) in the hippocampus, and VAMP1 (Vamp1) and neurexin 1 (Nrxn1) in the cortex were all significantly reduced in 12-month-old mice. Post mortem AD samples from the human hippocampus and cortex displayed lower expression of VAMP, synapsin, neurofilament light (NF-L) and synaptophysin. The potentially neuroprotective FTY720 reversed most AβPP-induced changes in gene expression (Cplx1, Stx1a, Snap25, and Nrxn1) in the 12-month-old hippocampus, which is thought to be most sensitive to early neurotoxic insults, but it only restored Vamp1 in the cortex and had no influence in 3-month-old brains. Further study may reveal the potential usefulness of FTY720 in the modulation of deregulated neuronal phenotype in AD brains.
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Affiliation(s)
- Henryk Jęśko
- Department of Cellular Signalling, Mossakowski Medical Research Institute, Polish Academy of Sciences, Warsaw, Poland
| | - Iga Wieczorek
- Laboratory of Preclinical Research and Environmental Agents, Mossakowski Medical Research Institute, Polish Academy of Sciences, Warsaw, Poland
| | - Przemysław Leonard Wencel
- Laboratory of Preclinical Research and Environmental Agents, Mossakowski Medical Research Institute, Polish Academy of Sciences, Warsaw, Poland
| | | | - Walter J. Lukiw
- LSU Neuroscience Center, Departments of Neurology and Ophthalmology, Louisiana State University School of Medicine, New Orleans, LA, United States
| | - Robert Piotr Strosznajder
- Laboratory of Preclinical Research and Environmental Agents, Mossakowski Medical Research Institute, Polish Academy of Sciences, Warsaw, Poland
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13
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Liang Y, Raven F, Ward JF, Zhen S, Zhang S, Sun H, Miller SJ, Choi SH, Tanzi RE, Zhang C. Upregulation of Alzheimer's Disease Amyloid-β Protein Precursor in Astrocytes Both in vitro and in vivo. J Alzheimers Dis 2021; 76:1071-1082. [PMID: 32597805 DOI: 10.3233/jad-200128] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND The amyloid cascade hypothesis of Alzheimer's disease (AD) posits that amyloid-β (Aβ) protein accumulation underlies the pathogenesis of the disease by leading to the formation of amyloid plaques, a pathologic hallmark of AD. Aβ is a proteolytic product of amyloid-β protein precursor (AβPP; APP), which is expressed in both neurons and astrocytes. Although considerable evidence shows that astrocytes may play critical roles in the pathogenesis of AD, the longitudinal changes of amyloid plaques in relationship to AβPP expression in astrocytes and cellular consequences are largely unknown. OBJECTIVE Here, we aimed to investigate astrocyte-related pathological changes of Aβ and AβPP using immunohistochemistry and biochemical studies in both animal and cell models. METHODS/RESULTS We utilized 5XFAD transgenic mice and found age-dependent upregulation of AβPP in astrocytes demonstrated with astrocytic reactive properties, which followed appearance of amyloid plaques in the brain. We also observed that AβPP proteins presented well-defined punctate immuno reactivity in young animals, whereas AβPP staining showed disrupted structures surrounding amyloid plaques in older mice. Moreover, we utilized astrocyte cell models and showed that pretreatment of Aβ42 resulted in downstream astrocyte autonomous changes, including up regulation in AβPP and BACE1 levels, as well as prolonged amyloidogenesis that could be reduced by pharmacological inhibition of BACE1. CONCLUSION Collectively, our results show that age-dependent AβPP up regulation in astrocytes is a key feature in AD, which will not only provide novel insights for understanding AD progression, but also may offer new therapeutic strategies for treating AD.
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Affiliation(s)
- Yingxia Liang
- Genetics and Aging Research Unit, McCance Center for Brain Health, MassGeneral Institute for Neurodegenerative Diseases (MIND), Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, USA.,Department of Anesthesiology, Weifang Medical University, Weifang, Shandong, China
| | - Frank Raven
- Genetics and Aging Research Unit, McCance Center for Brain Health, MassGeneral Institute for Neurodegenerative Diseases (MIND), Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, USA
| | - Joseph F Ward
- Genetics and Aging Research Unit, McCance Center for Brain Health, MassGeneral Institute for Neurodegenerative Diseases (MIND), Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, USA
| | - Sherri Zhen
- Genetics and Aging Research Unit, McCance Center for Brain Health, MassGeneral Institute for Neurodegenerative Diseases (MIND), Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, USA
| | - Siyi Zhang
- Genetics and Aging Research Unit, McCance Center for Brain Health, MassGeneral Institute for Neurodegenerative Diseases (MIND), Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, USA
| | - Haoqi Sun
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA
| | - Sean J Miller
- Genetics and Aging Research Unit, McCance Center for Brain Health, MassGeneral Institute for Neurodegenerative Diseases (MIND), Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, USA
| | - Se Hoon Choi
- Genetics and Aging Research Unit, McCance Center for Brain Health, MassGeneral Institute for Neurodegenerative Diseases (MIND), Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, USA
| | - Rudolph E Tanzi
- Genetics and Aging Research Unit, McCance Center for Brain Health, MassGeneral Institute for Neurodegenerative Diseases (MIND), Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, USA
| | - Can Zhang
- Genetics and Aging Research Unit, McCance Center for Brain Health, MassGeneral Institute for Neurodegenerative Diseases (MIND), Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, USA
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14
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Spiking Neural Network with Linear Computational Complexity for Waveform Analysis in Amperometry. SENSORS 2021; 21:s21093276. [PMID: 34068538 PMCID: PMC8125990 DOI: 10.3390/s21093276] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 05/03/2021] [Accepted: 05/08/2021] [Indexed: 11/17/2022]
Abstract
The paper describes the architecture of a Spiking Neural Network (SNN) for time waveform analyses using edge computing. The network model was based on the principles of preprocessing signals in the diencephalon and using tonic spiking and inhibition-induced spiking models typical for the thalamus area. The research focused on a significant reduction of the complexity of the SNN algorithm by eliminating most synaptic connections and ensuring zero dispersion of weight values concerning connections between neuron layers. The paper describes a network mapping and learning algorithm, in which the number of variables in the learning process is linearly dependent on the size of the patterns. The works included testing the stability of the accuracy parameter for various network sizes. The described approach used the ability of spiking neurons to process currents of less than 100 pA, typical of amperometric techniques. An example of a practical application is an analysis of vesicle fusion signals using an amperometric system based on Carbon NanoTube (CNT) sensors. The paper concludes with a discussion of the costs of implementing the network as a semiconductor structure.
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15
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Li J, Xu C, Zhang J, Jin C, Shi X, Zhang C, Jia S, Xu J, Gui X, Xing L, Lu L, Xu L. Identification of miRNA-Target Gene Pairs in the Parietal and Frontal Lobes of the Brain in Patients with Alzheimer's Disease Using Bioinformatic Analyses. Neurochem Res 2021; 46:964-979. [PMID: 33586092 DOI: 10.1007/s11064-020-03215-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 12/05/2020] [Accepted: 12/23/2020] [Indexed: 12/17/2022]
Abstract
Alzheimer's disease (AD) is a growing health concern worldwide. MicroRNAs (miRNAs) have been extensively studied in many diseases, including AD. To identify differentially expressed miRNAs (DEmiRNAs) and genes specific to AD, we used bioinformatic analyses to investigate candidate miRNA-mRNA pairs involved in the pathogenesis of AD. We focused on differentially expressed genes (DEGs) that are targets of DEmiRNAs. The GEO2R tool and the HISAT2-DESeq2 software were used to identify DEmiRNAs and DEGs. Bioinformatic tools available online, such as TAM and the Database for Annotation, Visualization and Integrated Discovery (DAVID), were used to perform functional annotation and enrichment analysis. Targets of miRNAs were predicted using the miRTarBase. The Search Tool for the Retrieval of Interacting Genes (STRING) and Cytoscape, which are available online, were utilized to construct protein-protein interaction (PPI) networks and identify hub genes. Furthermore, transcription factors (TFs) encoded by the DEGs were predicted using the TransmiR database and TF-miRNA-mRNA networks were constructed. Finally, the expression profile of a hub gene in peripheral blood mononuclear cells was compared between healthy individuals and AD patients. We identified 26 correlated miRNA-mRNA pairs. In the parietal lobe, miRNA-mRNA pairs involved in protein folding were enriched, and in the frontal lobe, miRNA-mRNA pairs involved in synaptic transmission, abnormal protein degradation, and apoptosis were enriched. In addition, HSP90AB1 in peripheral blood mononuclear cells was found to be significantly downregulated in AD patients, and this was consistent with its expression profile in the parietal lobe of AD patients. Our results provide brain region-specific changes in miRNA-mRNA associations in AD patients, further our understanding of potential underlying molecular mechanisms of AD, and reveal promising diagnostic and therapeutic targets for AD.
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Affiliation(s)
- Jiao Li
- Teaching Laboratory Center of Medicine and Life Science, Tongji University School of Medicine, Shanghai, 200092, China
| | - Chunli Xu
- Department of Neurology, The Seventh People's Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, 200137, China
| | - Junfang Zhang
- Teaching Laboratory Center of Medicine and Life Science, Tongji University School of Medicine, Shanghai, 200092, China
| | - Caixia Jin
- Department of Biochemistry and Molecular Biology, School of Medicine, Tongji University, Shanghai, China
| | - Xiujuan Shi
- Department of Biochemistry and Molecular Biology, School of Medicine, Tongji University, Shanghai, China
| | - Chen Zhang
- Department of Laboratory Research Center, Tongji University School of Medicine, Shanghai, China
| | - Song Jia
- Teaching Laboratory Center of Medicine and Life Science, Tongji University School of Medicine, Shanghai, 200092, China
| | - Jie Xu
- Teaching Laboratory Center of Medicine and Life Science, Tongji University School of Medicine, Shanghai, 200092, China
| | - Xin Gui
- School of Life Science and Technology, Tongji University, Shanghai, China
| | - Libo Xing
- School of Life Science and Technology, Tongji University, Shanghai, China
| | - Lixia Lu
- Department of Biochemistry and Molecular Biology, School of Medicine, Tongji University, Shanghai, China
| | - Lei Xu
- Department of Biochemistry and Molecular Biology, School of Medicine, Tongji University, Shanghai, China.
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16
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Escamilla-Ayala A, Wouters R, Sannerud R, Annaert W. Contribution of the Presenilins in the cell biology, structure and function of γ-secretase. Semin Cell Dev Biol 2020; 105:12-26. [DOI: 10.1016/j.semcdb.2020.02.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 02/06/2020] [Accepted: 02/17/2020] [Indexed: 01/25/2023]
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17
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Miyamoto M, Kuzuya A, Noda Y, Ueda S, Asada-Utsugi M, Ito S, Fukusumi Y, Kawachi H, Takahashi R, Kinoshita A. Synaptic Vesicle Protein 2B Negatively Regulates the Amyloidogenic Processing of AβPP as a Novel Interaction Partner of BACE1. J Alzheimers Dis 2020; 75:173-185. [DOI: 10.3233/jad-200071] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Masakazu Miyamoto
- Department of Neurology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
- Department of Human Health Science, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Akira Kuzuya
- Department of Neurology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Yasuha Noda
- Department of Human Health Science, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Sakiho Ueda
- Department of Neurology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Megumi Asada-Utsugi
- Department of Human Health Science, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Shinji Ito
- Medical Research Support Center, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Yoshiyasu Fukusumi
- Department of Cell Biology, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Hiroshi Kawachi
- Department of Cell Biology, Kidney Research Center, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Ryosuke Takahashi
- Department of Neurology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Ayae Kinoshita
- Department of Human Health Science, Graduate School of Medicine, Kyoto University, Kyoto, Japan
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18
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Maesako M, Zoltowska KM, Berezovska O. Synapsin 1 promotes Aβ generation via BACE1 modulation. PLoS One 2019; 14:e0226368. [PMID: 31830091 PMCID: PMC6907790 DOI: 10.1371/journal.pone.0226368] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Accepted: 11/25/2019] [Indexed: 12/26/2022] Open
Abstract
It has been revealed that β-amyloid (Aβ) is generated and released from the presynaptic terminals in activity-dependent manner. However, molecules modulating the presynaptic Aβ generation remain elusive. Here we test the hypothesis that Synapsin 1 (Syn1) may acts as a modulator of the Aβ production. Using biochemical and Förster resonance energy transfer (FRET)-based imaging approaches we have found that Syn1 knock down decreases, whereas (over)expression of Syn1 in cells increases the Aβ levels. Mechanistically, Syn1 does not seem to affect the activity of Presenilin 1 (PS1)/γ-secretase, PS1 conformation, or the proximity between PS1 and amyloid precursor protein (APP). However, we found that Syn1 is involved in up-regulation of the β-site APP cleaving enzyme 1 (BACE1)/β-secretase activity and increases the APP/BACE1 interaction. Therefore, we conclude that Syn1 may promote Aβ production via the modulation of BACE1.
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Affiliation(s)
- Masato Maesako
- MassGeneral Institute for Neurodegenerative Disease, Alzheimer’s Disease Research Unit, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, United States of America
| | - Katarzyna M. Zoltowska
- MassGeneral Institute for Neurodegenerative Disease, Alzheimer’s Disease Research Unit, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, United States of America
| | - Oksana Berezovska
- MassGeneral Institute for Neurodegenerative Disease, Alzheimer’s Disease Research Unit, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, United States of America
- * E-mail:
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19
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Jia L, Piña-Crespo J, Li Y. Restoring Wnt/β-catenin signaling is a promising therapeutic strategy for Alzheimer's disease. Mol Brain 2019; 12:104. [PMID: 31801553 PMCID: PMC6894260 DOI: 10.1186/s13041-019-0525-5] [Citation(s) in RCA: 171] [Impact Index Per Article: 34.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 11/26/2019] [Indexed: 01/01/2023] Open
Abstract
Alzheimer’s disease (AD) is an aging-related neurological disorder characterized by synaptic loss and dementia. Wnt/β-catenin signaling is an essential signal transduction pathway that regulates numerous cellular processes including cell survival. In brain, Wnt/β-catenin signaling is not only crucial for neuronal survival and neurogenesis, but it plays important roles in regulating synaptic plasticity and blood-brain barrier integrity and function. Moreover, activation of Wnt/β-catenin signaling inhibits amyloid-β production and tau protein hyperphosphorylation in the brain. Critically, Wnt/β-catenin signaling is greatly suppressed in AD brain via multiple pathogenic mechanisms. As such, restoring Wnt/β-catenin signaling represents a unique opportunity for the rational design of novel AD therapies.
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Affiliation(s)
- Lin Jia
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA.,Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, Medical College, Xiamen University, Xiamen, 361102, China
| | - Juan Piña-Crespo
- Neuroscience Initiative, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, 92037, USA
| | - Yonghe Li
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA.
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20
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Zhuang K, Huang C, Leng L, Zheng H, Gao Y, Chen G, Ji Z, Sun H, Hu Y, Wu D, Shi M, Li H, Zhao Y, Zhang Y, Xue M, Bu G, Huang TY, Xu H, Zhang J. Neuron-Specific Menin Deletion Leads to Synaptic Dysfunction and Cognitive Impairment by Modulating p35 Expression. Cell Rep 2019; 24:701-712. [PMID: 30021166 DOI: 10.1016/j.celrep.2018.06.055] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2018] [Revised: 05/03/2018] [Accepted: 06/12/2018] [Indexed: 10/28/2022] Open
Abstract
Menin (MEN1) is a critical modulator of tissue development and maintenance. As such, MEN1 mutations are associated with multiple endocrine neoplasia type 1 (MEN1) syndrome. Although menin is abundantly expressed in the nervous system, little is known with regard to its function in the adult brain. Here, we demonstrate that neuron-specific deletion of Men1 (CcKO) affects dendritic branching and spine formation, resulting in defects in synaptic function, learning, and memory. Furthermore, we find that menin binds to the p35 promoter region to facilitate p35 transcription. As a primary Cdk5 activator, p35 is expressed mainly in neurons and is critical for brain development and synaptic plasticity. Restoration of p35 expression in the hippocampus and cortex of Men1 CcKO mice rescues synaptic and cognitive deficits associated with Men1 deletion. These results reveal a critical role for menin in synaptic and cognitive function by modulating the p35-Cdk5 pathway.
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Affiliation(s)
- Kai Zhuang
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, Medical College, Xiamen University, Xiamen, Fujian 361102, China
| | - Changquan Huang
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, Medical College, Xiamen University, Xiamen, Fujian 361102, China
| | - Lige Leng
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, Medical College, Xiamen University, Xiamen, Fujian 361102, China
| | - Honghua Zheng
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, Medical College, Xiamen University, Xiamen, Fujian 361102, China
| | - Yuehong Gao
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, Medical College, Xiamen University, Xiamen, Fujian 361102, China
| | - Guimiao Chen
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, Medical College, Xiamen University, Xiamen, Fujian 361102, China
| | - Zhilin Ji
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, Medical College, Xiamen University, Xiamen, Fujian 361102, China
| | - Hao Sun
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, Medical College, Xiamen University, Xiamen, Fujian 361102, China
| | - Yu Hu
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, Medical College, Xiamen University, Xiamen, Fujian 361102, China
| | - Di Wu
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, Medical College, Xiamen University, Xiamen, Fujian 361102, China
| | - Meng Shi
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, Medical College, Xiamen University, Xiamen, Fujian 361102, China
| | - Huifang Li
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, Medical College, Xiamen University, Xiamen, Fujian 361102, China
| | - Yingjun Zhao
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, Medical College, Xiamen University, Xiamen, Fujian 361102, China; Neuroscience Initiative, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Yunwu Zhang
- Neuroscience Initiative, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Maoqiang Xue
- Department of Basic Medical Science, Medical College, Xiamen University, Xiamen, Fujian 361102, China
| | - Guojun Bu
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, Medical College, Xiamen University, Xiamen, Fujian 361102, China; Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Timothy Y Huang
- Neuroscience Initiative, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Huaxi Xu
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, Medical College, Xiamen University, Xiamen, Fujian 361102, China; Neuroscience Initiative, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Jie Zhang
- Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, Medical College, Xiamen University, Xiamen, Fujian 361102, China.
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21
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Presenilin 1 increases association with synaptotagmin 1 during normal aging. Neurobiol Aging 2019; 86:156-161. [PMID: 31864759 PMCID: PMC7325863 DOI: 10.1016/j.neurobiolaging.2019.10.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 10/10/2019] [Accepted: 10/10/2019] [Indexed: 12/05/2022]
Abstract
Presenilin 1 (PS1), the catalytic component of gamma secretase, associates with synaptotagmin 1 (Syt-1). This interaction is decreased in the brains of patients with sporadic Alzheimer’s disease. However, it remains unclear how this interaction changes during normal aging. Because aging is a risk factor for Alzheimer’s disease, we sought to identify changes in PS1 and Syt-1 association during aging in primary neurons in vitro and mouse brain sections ex vivo. We also tested the effect of aging on the calcium dependence of the interaction by treating neurons aged in vitro with KCl. We found that PS1 and Syt-1 increase their association with age, an effect that is more robust in neuronal processes than cell bodies. Treatment with KCl triggered the interaction in both young and old neurons. Baseline calcium levels and calcium in ux in response to KCl treatment were significantly higher in older neurons, which can partially explain the increase in PS1/Syt-1 binding with age. These results suggest a compensatory mechanism during normal aging to offset detrimental age-associated effects.
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22
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Wingo AP, Dammer EB, Breen MS, Logsdon BA, Duong DM, Troncosco JC, Thambisetty M, Beach TG, Serrano GE, Reiman EM, Caselli RJ, Lah JJ, Seyfried NT, Levey AI, Wingo TS. Large-scale proteomic analysis of human brain identifies proteins associated with cognitive trajectory in advanced age. Nat Commun 2019; 10:1619. [PMID: 30962425 PMCID: PMC6453881 DOI: 10.1038/s41467-019-09613-z] [Citation(s) in RCA: 115] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Accepted: 03/12/2019] [Indexed: 01/14/2023] Open
Abstract
In advanced age, some individuals maintain a stable cognitive trajectory while others experience a rapid decline. Such variation in cognitive trajectory is only partially explained by traditional neurodegenerative pathologies. Hence, to identify new processes underlying variation in cognitive trajectory, we perform an unbiased proteome-wide association study of cognitive trajectory in a discovery (n = 104) and replication cohort (n = 39) of initially cognitively unimpaired, longitudinally assessed older-adult brain donors. We find 579 proteins associated with cognitive trajectory after meta-analysis. Notably, we present evidence for increased neuronal mitochondrial activities in cognitive stability regardless of the burden of traditional neuropathologies. Furthermore, we provide additional evidence for increased synaptic abundance and decreased inflammation and apoptosis in cognitive stability. Importantly, we nominate proteins associated with cognitive trajectory, particularly the 38 proteins that act independently of neuropathologies and are also hub proteins of protein co-expression networks, as promising targets for future mechanistic studies of cognitive trajectory.
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Affiliation(s)
- Aliza P. Wingo
- Division of Mental Health, Atlanta VA Medical Center, Decatur, GA 30033 USA
- Department of Psychiatry, Emory University School of Medicine, Atlanta, GA 30322 USA
| | - Eric B. Dammer
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322 USA
| | - Michael S. Breen
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
- Department of Genetic and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
- Seaver Autism Center for Research and Treatment, Icahn School of Medicine at Mount Sinai, New York, NY 10029 USA
| | | | - Duc M. Duong
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322 USA
| | | | - Madhav Thambisetty
- Unit of Clinical and Translational Neuroscience, Laboratory of Behavioral Neuroscience, National Institute on Aging, National Institutes of Health, Bethesda, MD 20892 USA
| | - Thomas G. Beach
- Banner Sun Health Research Institute, Sun City, AZ 85351 USA
| | | | - Eric M. Reiman
- Banner Alzheimer’s Institute, Arizona State University and University of Arizona, Phoenix, AZ 85351 USA
| | | | - James J. Lah
- Department of Neurology, Emory University School of Medicine, Atlanta, GA 30322 USA
| | - Nicholas T. Seyfried
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322 USA
| | - Allan I. Levey
- Department of Neurology, Emory University School of Medicine, Atlanta, GA 30322 USA
| | - Thomas S. Wingo
- Department of Neurology, Emory University School of Medicine, Atlanta, GA 30322 USA
- Division of Neurology, Atlanta VA Medical Center, Decatur, GA 30033 USA
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322 USA
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23
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Novel interaction between Alzheimer's disease-related protein presenilin 1 and glutamate transporter 1. Sci Rep 2018; 8:8718. [PMID: 29880815 PMCID: PMC5992168 DOI: 10.1038/s41598-018-26888-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Accepted: 05/18/2018] [Indexed: 12/28/2022] Open
Abstract
Neuronal hyperactivity is one of the earliest events observed in Alzheimer’s disease (AD). Moreover, alterations in the expression of glutamate transporters have been reported to exacerbate amyloid pathology and cognitive deficits in transgenic AD mouse models. However, the molecular links between these pathophysiological changes remain largely unknown. Here, we report novel interaction between presenilin 1 (PS1), the catalytic component of the amyloid precursor protein-processing enzyme, γ-secretase, and a major glutamate transporter-1 (GLT-1). Our data demonstrate that the interaction occurs between PS1 and GLT-1 expressed at their endogenous levels in vivo and in vitro, takes place in both neurons and astrocytes, and is independent of the PS1 autoproteolysis and γ-secretase activity. This intriguing discovery may shed light on the molecular crosstalk between the proteins linked to the maintenance of glutamate homeostasis and Aβ pathology.
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Qin W, Lu H. A novel joint analysis framework improves identification of differentially expressed genes in cross disease transcriptomic analysis. BioData Min 2018; 11:3. [PMID: 29467826 PMCID: PMC5819186 DOI: 10.1186/s13040-018-0163-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2017] [Accepted: 01/29/2018] [Indexed: 11/22/2022] Open
Abstract
Motivation Detecting differentially expressed (DE) genes between disease and normal control group is one of the most common analyses in genome-wide transcriptomic data. Since most studies don’t have a lot of samples, researchers have used meta-analysis to group different datasets for the same disease. Even then, in many cases the statistical power is still not enough. Taking into account the fact that many diseases share the same disease genes, it is desirable to design a statistical framework that can identify diseases’ common and specific DE genes simultaneously to improve the identification power. Results We developed a novel empirical Bayes based mixture model to identify DE genes in specific study by leveraging the shared information across multiple different disease expression data sets. The effectiveness of joint analysis was demonstrated through comprehensive simulation studies and two real data applications. The simulation results showed that our method consistently outperformed single data set analysis and two other meta-analysis methods in identification power. In real data analysis, overall our method demonstrated better identification power in detecting DE genes and prioritized more disease related genes and disease related pathways than single data set analysis. Over 150% more disease related genes are identified by our method in application to Huntington’s disease. We expect that our method would provide researchers a new way of utilizing available data sets from different diseases when sample size of the focused disease is limited. Electronic supplementary material The online version of this article (10.1186/s13040-018-0163-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Wenyi Qin
- 1Department of Bioengineering, University of Illinois at Chicago, 851 S. Morgan, Rm 218, Chicago, IL 60607 USA
| | - Hui Lu
- 1Department of Bioengineering, University of Illinois at Chicago, 851 S. Morgan, Rm 218, Chicago, IL 60607 USA.,2SJTU-Yale Joint Center for Biostatistics, Department of Bioinformatics and Biostatistics, Shanghai Jiaotong University, Shanghai, China.,Shanghai Engineering Research Center for Big Data in Pediatric Precision Medicine, Shanghai, China
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Raven F, Ward JF, Zoltowska KM, Wan Y, Bylykbashi E, Miller SJ, Shen X, Choi SH, Rynearson KD, Berezovska O, Wagner SL, Tanzi RE, Zhang C. Soluble Gamma-secretase Modulators Attenuate Alzheimer's β-amyloid Pathology and Induce Conformational Changes in Presenilin 1. EBioMedicine 2017; 24:93-101. [PMID: 28919280 PMCID: PMC5652037 DOI: 10.1016/j.ebiom.2017.08.028] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 08/18/2017] [Accepted: 08/31/2017] [Indexed: 11/29/2022] Open
Abstract
A central pathogenic event of Alzheimer's disease (AD) is the accumulation of the Aβ42 peptide, which is generated from amyloid-β precursor protein (APP) via cleavages by β- and γ-secretase. We have developed a class of soluble 2-aminothiazole γ-secretase modulators (SGSMs) that preferentially decreases Aβ42 levels. However, the effects of SGSMs in AD animals and cells expressing familial AD mutations, as well as the mechanism of γ-secretase modulation remain largely unknown. Here, a representative of this SGSM scaffold, SGSM-36, was investigated using animals and cells expressing FAD mutations. SGSM-36 preferentially reduced Aβ42 levels without affecting either α- and β-secretase processing of APP nor Notch processing. Furthermore, an allosteric site was identified within the γ-secretase complex that allowed access of SGSM-36 using cell-based, fluorescence lifetime imaging microscopy analysis. Collectively, these studies provide mechanistic insights regarding SGSMs of this class and reinforce their therapeutic potential in AD. A novel class soluble 2-aminothiazole γ-secretase modulators (SGSMs) are characterized as potential therapeutics for AD. A representative compound, SGSM-36, preferentially decreases Aβ42 levels using animal and cell models of AD. An allosteric site was identified within γ-secretase to be accessible by SGSM-36.
Alzheimer's disease (AD) is a devastating neurodegenerative disorder and there is currently no treatment to slow or halt disease progression. Considerable evidence shows that the primary pathological event leading to AD is the production and accumulation of Aβ42 peptide. We have developed a class of soluble 2-aminothiazole γ-secretase modulators (SGSMs) that preferentially decreases Aβ42 levels. The presented studies have primarily elucidated the mechanisms by which our SGSMs decrease Aβ42 levels and attenuate β-amyloid pathology. The results of these experiments will be useful toward the ongoing efforts toward the development of an effective therapy for the treatment and prevention of AD.
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Affiliation(s)
- Frank Raven
- Genetics and Aging Research Unit, MassGeneral Institute for Neurodegenerative Diseases (MIND), Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129-2060, USA; Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen 9747 AG, The Netherlands
| | - Joseph F Ward
- Genetics and Aging Research Unit, MassGeneral Institute for Neurodegenerative Diseases (MIND), Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129-2060, USA
| | - Katarzyna M Zoltowska
- Alzheimer Research Unit, MassGeneral Institute for Neurodegenerative Diseases (MIND), Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129-2060, USA
| | - Yu Wan
- Genetics and Aging Research Unit, MassGeneral Institute for Neurodegenerative Diseases (MIND), Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129-2060, USA; Department of Neurology, Qingdao Municipal Hospital, Qingdao University, PR China
| | - Enjana Bylykbashi
- Genetics and Aging Research Unit, MassGeneral Institute for Neurodegenerative Diseases (MIND), Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129-2060, USA
| | - Sean J Miller
- Genetics and Aging Research Unit, MassGeneral Institute for Neurodegenerative Diseases (MIND), Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129-2060, USA
| | - Xunuo Shen
- Genetics and Aging Research Unit, MassGeneral Institute for Neurodegenerative Diseases (MIND), Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129-2060, USA
| | - Se Hoon Choi
- Genetics and Aging Research Unit, MassGeneral Institute for Neurodegenerative Diseases (MIND), Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129-2060, USA
| | - Kevin D Rynearson
- Department of Neurosciences, University of California, La Jolla, San Diego, CA 92093-0624, USA
| | - Oksana Berezovska
- Alzheimer Research Unit, MassGeneral Institute for Neurodegenerative Diseases (MIND), Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129-2060, USA
| | - Steven L Wagner
- Department of Neurosciences, University of California, La Jolla, San Diego, CA 92093-0624, USA; Research Biologist, VA San Diego Healthcare System, La Jolla, CA, 92161, United States.
| | - Rudolph E Tanzi
- Genetics and Aging Research Unit, MassGeneral Institute for Neurodegenerative Diseases (MIND), Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129-2060, USA.
| | - Can Zhang
- Genetics and Aging Research Unit, MassGeneral Institute for Neurodegenerative Diseases (MIND), Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129-2060, USA.
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Dynamic Nature of presenilin1/γ-Secretase: Implication for Alzheimer's Disease Pathogenesis. Mol Neurobiol 2017; 55:2275-2284. [PMID: 28332150 DOI: 10.1007/s12035-017-0487-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Accepted: 03/12/2017] [Indexed: 12/27/2022]
Abstract
Presenilin 1 (PS1) is a catalytic component of the γ-secretase complex, responsible for the intramembraneous cleavage of more than 90 type I transmembrane proteins, including Alzheimer's disease (AD)-related amyloid precursor protein (APP). The γ-secretase-mediated cleavage of the APP C-terminal membrane stub leads to the production of various amyloid β (Aβ) species. The assembly of Aβ into neurotoxic oligomers, which causes synaptic dysfunction and neurodegeneration, is influenced by the relative ratio of the longer (Aβ42/43) to shorter Aβ (Aβ40) peptides. The ratio of Aβ42 to Aβ40 depends on the conformation and activity of the PS1/γ-secretase enzymatic complex. The latter exists in a dynamic equilibrium of the so called "closed" and "open" conformational states, as determined by the Förster resonance energy transfer (FRET)-based PS1 conformation assay. Here we review several factors that can allosterically influence conformational status of the enzyme, and hence the production of Aβ peptides. These include genetic variations in PS1, APP and other γ-secretase components, environmental stressors implicated in AD pathogenesis and pharmacological agents. Since "closed" PS1 conformation is the common outcome of many AD-related insults, the novel assays monitoring PS1 conformation in live/intact cells in vivo and in vitro might be utilized for diagnostic purposes and for validation of the potential therapeutic approaches.
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