1
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Tang Y, Zhang Y, Zhang D, Liu Y, Nussinov R, Zheng J. Exploring pathological link between antimicrobial and amyloid peptides. Chem Soc Rev 2024; 53:8713-8763. [PMID: 39041297 DOI: 10.1039/d3cs00878a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/24/2024]
Abstract
Amyloid peptides (AMYs) and antimicrobial peptides (AMPs) are considered as the two distinct families of peptides, characterized by their unique sequences, structures, biological functions, and specific pathological targets. However, accumulating evidence has revealed intriguing pathological connections between these peptide families in the context of microbial infection and neurodegenerative diseases. Some AMYs and AMPs share certain structural and functional characteristics, including the ability to self-assemble, the presence of β-sheet-rich structures, and membrane-disrupting mechanisms. These shared features enable AMYs to possess antimicrobial activity and AMPs to acquire amyloidogenic properties. Despite limited studies on AMYs-AMPs systems, the cross-seeding phenomenon between AMYs and AMPs has emerged as a crucial factor in the bidirectional communication between the pathogenesis of neurodegenerative diseases and host defense against microbial infections. In this review, we examine recent developments in the potential interplay between AMYs and AMPs, as well as their pathological implications for both infectious and neurodegenerative diseases. By discussing the current progress and challenges in this emerging field, this account aims to inspire further research and investments to enhance our understanding of the intricate molecular crosstalk between AMYs and AMPs. This knowledge holds great promise for the development of innovative therapies to combat both microbial infections and neurodegenerative disorders.
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Affiliation(s)
- Yijing Tang
- Department of Chemical, Biomolecular, and Corrosion Engineering, The University of Akron, Ohio 44325, USA.
| | - Yanxian Zhang
- Division of Endocrinology and Diabetes, Department of Pediatrics, School of Medicine, Stanford University, Palo Alto, CA 94304, USA
| | - Dong Zhang
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia 30332, USA
| | - Yonglan Liu
- Cancer Innovation Laboratory, National Cancer Institute, Frederick, MD 21702, USA
| | - Ruth Nussinov
- Computational Structural Biology Section, Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA.
- Department of Human Molecular Genetics and Biochemistry Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Jie Zheng
- Department of Chemical, Biomolecular, and Corrosion Engineering, The University of Akron, Ohio 44325, USA.
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2
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Balczon R, Lin MT, Voth S, Nelson AR, Schupp JC, Wagener BM, Pittet JF, Stevens T. Lung endothelium, tau, and amyloids in health and disease. Physiol Rev 2024; 104:533-587. [PMID: 37561137 PMCID: PMC11281824 DOI: 10.1152/physrev.00006.2023] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 06/26/2023] [Accepted: 08/04/2023] [Indexed: 08/11/2023] Open
Abstract
Lung endothelia in the arteries, capillaries, and veins are heterogeneous in structure and function. Lung capillaries in particular represent a unique vascular niche, with a thin yet highly restrictive alveolar-capillary barrier that optimizes gas exchange. Capillary endothelium surveys the blood while simultaneously interpreting cues initiated within the alveolus and communicated via immediately adjacent type I and type II epithelial cells, fibroblasts, and pericytes. This cell-cell communication is necessary to coordinate the immune response to lower respiratory tract infection. Recent discoveries identify an important role for the microtubule-associated protein tau that is expressed in lung capillary endothelia in the host-pathogen interaction. This endothelial tau stabilizes microtubules necessary for barrier integrity, yet infection drives production of cytotoxic tau variants that are released into the airways and circulation, where they contribute to end-organ dysfunction. Similarly, beta-amyloid is produced during infection. Beta-amyloid has antimicrobial activity, but during infection it can acquire cytotoxic activity that is deleterious to the host. The production and function of these cytotoxic tau and amyloid variants are the subject of this review. Lung-derived cytotoxic tau and amyloid variants are a recently discovered mechanism of end-organ dysfunction, including neurocognitive dysfunction, during and in the aftermath of infection.
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Affiliation(s)
- Ron Balczon
- Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, Alabama, United States
- Center for Lung Biology, University of South Alabama, Mobile, Alabama, United States
| | - Mike T Lin
- Department of Physiology and Cell Biology, University of South Alabama, Mobile, Alabama, United States
- Center for Lung Biology, University of South Alabama, Mobile, Alabama, United States
| | - Sarah Voth
- Department of Cell Biology and Physiology, Edward Via College of Osteopathic Medicine, Monroe, Louisiana, United States
| | - Amy R Nelson
- Department of Physiology and Cell Biology, University of South Alabama, Mobile, Alabama, United States
- Center for Lung Biology, University of South Alabama, Mobile, Alabama, United States
| | - Jonas C Schupp
- Pulmonary and Critical Care Medicine, Department of Internal Medicine, Yale University, New Haven, Connecticut, United States
- Department of Respiratory Medicine, Hannover Medical School, Hannover, Germany
- German Center for Lung Research (DZL), Hannover, Germany
| | - Brant M Wagener
- Department of Anesthesiology and Perioperative Medicine, University of Alabama-Birmingham, Birmingham, Alabama, United States
| | - Jean-Francois Pittet
- Department of Anesthesiology and Perioperative Medicine, University of Alabama-Birmingham, Birmingham, Alabama, United States
| | - Troy Stevens
- Department of Physiology and Cell Biology, University of South Alabama, Mobile, Alabama, United States
- Department of Internal Medicine, University of South Alabama, Mobile, Alabama, United States
- Center for Lung Biology, University of South Alabama, Mobile, Alabama, United States
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3
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Wang K, Cai W. Binding mechanism of full-length Aβ40 peptide to a mixed lipid bilayer. Front Chem 2024; 12:1367793. [PMID: 38449479 PMCID: PMC10914957 DOI: 10.3389/fchem.2024.1367793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Accepted: 02/05/2024] [Indexed: 03/08/2024] Open
Abstract
The destructive effect of Aβ peptides on membranes is an important source of its cytotoxicity in the pathogenesis of Alzheimer's disease. We have investigated the binding mechanism between the Aβ42 peptide and bilayer in our former work. However, as another abundant form of Aβ peptides in the physiological environment, the binding mechanism between Aβ40 peptide and the lipid bilayer still remains ambiguous. Hence, we performed all-atom simulations on the Aβ40 peptides with the lipid bilayer herein using replica exchange with the solute tempering 2 method. We obtained four major binding models with the hydrophobic C-terminus as the most preferable binding region. Hydrophobic residues and positively charged residues are the principal residues involved in the peptide-bilayer interactions. Aβ40 peptides in our simulation mainly adopt a β-rich conformation in both bound and unbound states. Besides, we determined peptide-water interactions and found that bound peptides prefer forming hydrogen bonds with water molecules than unbound peptides. Our findings herein may provide new insights for the in-depth understanding of the membrane-destructive mechanism of Aβ peptides.
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Affiliation(s)
| | - Wensheng Cai
- Research Center for Analytical Sciences, College of Chemistry, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Nankai University, Tianjin, China
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4
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Sarkar D, Bhunia A. Delineating the Role of GxxxG Motif in Amyloidogenesis: A New Perspective in Targeting Amyloid-Beta Mediated AD Pathogenesis. ACS BIO & MED CHEM AU 2024; 4:4-19. [PMID: 38404748 PMCID: PMC10885112 DOI: 10.1021/acsbiomedchemau.3c00055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 10/18/2023] [Accepted: 10/18/2023] [Indexed: 02/27/2024]
Abstract
The pursuit of a novel structural motif that can shed light on the key functional attributes is a primary focus in the study of protein folding disorders. Decades of research on Alzheimer's disease (AD) have centered on the Amyloid β (Aβ) pathway, highlighting its significance in understanding the disorder. The diversity in the Aβ pathway and the possible silent tracks which are yet to discover, makes it exceedingly intimidating to the interdisciplinary scientific community. Over the course of AD research, Aβ has consistently been at the forefront of scientific inquiry and discussion. In this review, we epitomize the role of a potential structural motif (GxxxG motif) that may provide a new horizon to the Aβ conflict. We emphasize on how comprehensive understanding of this motif from a structure-function perspective may pave the way for designing novel therapeutics intervention in AD and related diseases.
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Affiliation(s)
- Dibakar Sarkar
- Department of Chemical Sciences, Bose Institute, Unified Academic Campus, Sector V, Salt Lake EN
80, Kolkata 700 091, India
| | - Anirban Bhunia
- Department of Chemical Sciences, Bose Institute, Unified Academic Campus, Sector V, Salt Lake EN
80, Kolkata 700 091, India
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5
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Wang K, Cai W. Aggregation, structure and water permeability of membrane-embedded helical Aβ oligomers. Phys Chem Chem Phys 2024; 26:5128-5140. [PMID: 38259193 DOI: 10.1039/d3cp05317b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
It is widely recognized that membranes can facilitate the aggregation of amyloid-β (Aβ) peptides, while Aβ can in turn cause membrane damage. Many studies focus on the peptide-membrane interactions of Aβ oligomers with β-rich structures. However, the exact aggregation and toxicity mechanism of the membrane-embedded helical Aβ oligomers remain ambiguous. Herein, the molecular dynamics simulations were performed on membrane-embedded helical Aβ42 peptides. Initiated by eight Aβ42 monomers embedded in a lipid bilayer, the monomers aggregate into oligomers with stable transmembrane helix structures. With the aggregation of peptides, the membrane perturbations caused by Aβ aggregates decrease. The molecular architectures of oligomers were characterized and a helix-rich octamer stabilized by an annular network of hydrogen bonds was observed. The oligomers demonstrate the capability to assist transmembrane water transport. Our study may provide new insights for the investigation of transmembrane Aβ oligomers.
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Affiliation(s)
- Ke Wang
- Research Center for Analytical Sciences, College of Chemistry, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Nankai University, Tianjin 300071, China.
| | - Wensheng Cai
- Research Center for Analytical Sciences, College of Chemistry, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Nankai University, Tianjin 300071, China.
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6
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Dadkhah M, Baziar M, Rezaei N. The regulatory role of BDNF in neuroimmune axis function and neuroinflammation induced by chronic stress: A new therapeutic strategies for neurodegenerative disorders. Cytokine 2024; 174:156477. [PMID: 38147741 DOI: 10.1016/j.cyto.2023.156477] [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: 07/15/2023] [Revised: 11/14/2023] [Accepted: 12/10/2023] [Indexed: 12/28/2023]
Abstract
Neurodegenerative disorders account for a high proportion of neurological diseases that significantly threaten public health worldwide. Various factors are involved in the pathophysiology of such diseases which can lead to neurodegeneration and neural damage. Furthermore, neuroinflammation is a well-known factor in predisposing factors of neurological and especially neurodegenerative disorders which can be strongly suppressed by "anti-inflammatory" actions of brain-derived neurotrophic factor (BDNF). Stress has has also been identified as a risk factor in developing neurodegenerative disorders potentially leading to increased neuroinflammation in the brain and progressive loss in neuronal structures and impaired functions in the CNS. Recently, more studies have increasingly been focused on the role of neuroimmune system in regulating the neurobiology of stress. Emerging evidence indicate that exposure to chronic stress might alter the susceptibility to neurodegeneration via influencing the microglia function. Microglia is considered as the first responding group of cells in suppressing neuroinflammation, leading to an increased inflammatory cytokine signaling that promote the synaptic plasticity deficiencies, impairment in neurogenesis, and development of neurodegenerative disorders. In this review we discuss how exposure to chronic stress might alter the neuroimmune response potentially leading to progress of neurodegenerative disorders. We also emphasize on the role of BDNF in regulating the neuroimmune axis function and microglia modulation in neurodegenerative disorders.
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Affiliation(s)
- Masoomeh Dadkhah
- Pharmaceutical Sciences Research Center, Ardabil University of Medical Sciences, Ardabil, Iran.
| | - Milad Baziar
- Student Research Committee, Faculty of Medicine, Ardabil University of Medical Sciences, Ardabil, Iran
| | - Nima Rezaei
- Research Center for Immunodeficiencies, Children's Medical Center Hospital, Tehran University of Medical Sciences, Tehran 1419733151, Iran; Department of Immunology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran; Network of Immunity in Infection, Malignancy and Autoimmunity (NIIMA), Universal Scientific Education Research Network (USERN), Tehran, Iran
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7
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Ghasemitarei M, Ghorbi T, Yusupov M, Zhang Y, Zhao T, Shali P, Bogaerts A. Effects of Nitro-Oxidative Stress on Biomolecules: Part 1-Non-Reactive Molecular Dynamics Simulations. Biomolecules 2023; 13:1371. [PMID: 37759771 PMCID: PMC10527456 DOI: 10.3390/biom13091371] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 09/04/2023] [Accepted: 09/04/2023] [Indexed: 09/29/2023] Open
Abstract
Plasma medicine, or the biomedical application of cold atmospheric plasma (CAP), is an expanding field within plasma research. CAP has demonstrated remarkable versatility in diverse biological applications, including cancer treatment, wound healing, microorganism inactivation, and skin disease therapy. However, the precise mechanisms underlying the effects of CAP remain incompletely understood. The therapeutic effects of CAP are largely attributed to the generation of reactive oxygen and nitrogen species (RONS), which play a crucial role in the biological responses induced by CAP. Specifically, RONS produced during CAP treatment have the ability to chemically modify cell membranes and membrane proteins, causing nitro-oxidative stress, thereby leading to changes in membrane permeability and disruption of cellular processes. To gain atomic-level insights into these interactions, non-reactive molecular dynamics (MD) simulations have emerged as a valuable tool. These simulations facilitate the examination of larger-scale system dynamics, including protein-protein and protein-membrane interactions. In this comprehensive review, we focus on the applications of non-reactive MD simulations in studying the effects of CAP on cellular components and interactions at the atomic level, providing a detailed overview of the potential of CAP in medicine. We also review the results of other MD studies that are not related to plasma medicine but explore the effects of nitro-oxidative stress on cellular components and are therefore important for a broader understanding of the underlying processes.
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Affiliation(s)
- Maryam Ghasemitarei
- Department of Physics, Sharif University of Technology, Tehran 14588-89694, Iran
- Research Group PLASMANT, Department of Chemistry, University of Antwerp, 2610 Antwerp, Belgium
| | - Tayebeh Ghorbi
- Department of Physics, Sharif University of Technology, Tehran 14588-89694, Iran
| | - Maksudbek Yusupov
- School of Engineering, New Uzbekistan University, Tashkent 100007, Uzbekistan
- School of Engineering, Central Asian University, Tashkent 111221, Uzbekistan
- Laboratory of Thermal Physics of Multiphase Systems, Arifov Institute of Ion-Plasma and Laser Technologies, Academy of Sciences of Uzbekistan, Tashkent 100125, Uzbekistan
- Research Group PLASMANT, Department of Chemistry, University of Antwerp, 2610 Antwerp, Belgium
| | - Yuantao Zhang
- School of Electrical Engineering, Shandong University, Jinan 250061, China
| | - Tong Zhao
- School of Electrical Engineering, Shandong University, Jinan 250061, China
| | - Parisa Shali
- Research Unit Plasma Technology, Department of Applied Physics, Faculty of Engineering and Agriculture, Ghent University, 9000 Ghent, Belgium
| | - Annemie Bogaerts
- Research Group PLASMANT, Department of Chemistry, University of Antwerp, 2610 Antwerp, Belgium
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8
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Viles JH. Imaging Amyloid-β Membrane Interactions: Ion-Channel Pores and Lipid-Bilayer Permeability in Alzheimer's Disease. ANGEWANDTE CHEMIE (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 135:e202215785. [PMID: 38515735 PMCID: PMC10952214 DOI: 10.1002/ange.202215785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Indexed: 03/08/2023]
Abstract
The accumulation of the amyloid-β peptides (Aβ) is central to the development of Alzheimer's disease. The mechanism by which Aβ triggers a cascade of events that leads to dementia is a topic of intense investigation. Aβ self-associates into a series of complex assemblies with different structural and biophysical properties. It is the interaction of these oligomeric, protofibril and fibrillar assemblies with lipid membranes, or with membrane receptors, that results in membrane permeability and loss of cellular homeostasis, a key event in Alzheimer's disease pathology. Aβ can have an array of impacts on lipid membranes, reports have included: a carpeting effect; a detergent effect; and Aβ ion-channel pore formation. Recent advances imaging these interactions are providing a clearer picture of Aβ induced membrane disruption. Understanding the relationship between different Aβ structures and membrane permeability will inform therapeutics targeting Aβ cytotoxicity.
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Affiliation(s)
- John H. Viles
- Department of Biochemistry, SBBS, Queen MaryUniversity of LondonUK
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9
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Viles JH. Imaging Amyloid-β Membrane Interactions: Ion-Channel Pores and Lipid-Bilayer Permeability in Alzheimer's Disease. Angew Chem Int Ed Engl 2023; 62:e202215785. [PMID: 36876912 PMCID: PMC10953358 DOI: 10.1002/anie.202215785] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 03/02/2023] [Accepted: 03/03/2023] [Indexed: 03/07/2023]
Abstract
The accumulation of the amyloid-β peptides (Aβ) is central to the development of Alzheimer's disease. The mechanism by which Aβ triggers a cascade of events that leads to dementia is a topic of intense investigation. Aβ self-associates into a series of complex assemblies with different structural and biophysical properties. It is the interaction of these oligomeric, protofibril and fibrillar assemblies with lipid membranes, or with membrane receptors, that results in membrane permeability and loss of cellular homeostasis, a key event in Alzheimer's disease pathology. Aβ can have an array of impacts on lipid membranes, reports have included: a carpeting effect; a detergent effect; and Aβ ion-channel pore formation. Recent advances imaging these interactions are providing a clearer picture of Aβ induced membrane disruption. Understanding the relationship between different Aβ structures and membrane permeability will inform therapeutics targeting Aβ cytotoxicity.
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Affiliation(s)
- John H. Viles
- Department of Biochemistry, SBBS, Queen MaryUniversity of LondonUK
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10
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Bulgart HR, Goncalves I, Weisleder N. Leveraging Plasma Membrane Repair Therapeutics for Treating Neurodegenerative Diseases. Cells 2023; 12:1660. [PMID: 37371130 DOI: 10.3390/cells12121660] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 06/12/2023] [Accepted: 06/16/2023] [Indexed: 06/29/2023] Open
Abstract
Plasma membrane repair is an essential cellular mechanism that reseals membrane disruptions after a variety of insults, and compromised repair capacity can contribute to the progression of many diseases. Neurodegenerative diseases are marked by membrane damage from many sources, reduced membrane integrity, elevated intracellular calcium concentrations, enhanced reactive oxygen species production, mitochondrial dysfunction, and widespread neuronal death. While the toxic intracellular effects of these changes in cellular physiology have been defined, the specific mechanism of neuronal death in certain neurodegenerative diseases remains unclear. An abundance of recent evidence indicates that neuronal membrane damage and pore formation in the membrane are key contributors to neurodegenerative disease pathogenesis. In this review, we have outlined evidence supporting the hypothesis that membrane damage is a contributor to neurodegenerative diseases and that therapeutically enhancing membrane repair can potentially combat neuronal death.
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Affiliation(s)
- Hannah R Bulgart
- Department of Physiology & Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, College of Medicine, The Ohio State University Wexner Medical Center, Columbus, OH 43210, USA
| | - Isabella Goncalves
- Department of Physiology & Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, College of Medicine, The Ohio State University Wexner Medical Center, Columbus, OH 43210, USA
| | - Noah Weisleder
- Department of Physiology & Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, College of Medicine, The Ohio State University Wexner Medical Center, Columbus, OH 43210, USA
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11
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Wang B, Fang T, Chen H. Zinc and Central Nervous System Disorders. Nutrients 2023; 15:2140. [PMID: 37432243 DOI: 10.3390/nu15092140] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2023] [Revised: 04/26/2023] [Accepted: 04/27/2023] [Indexed: 07/12/2023] Open
Abstract
Zinc (Zn2+) is the second most abundant necessary trace element in the human body, exerting a critical role in many physiological processes such as cellular proliferation, transcription, apoptosis, growth, immunity, and wound healing. It is an essential catalyst ion for many enzymes and transcription factors. The maintenance of Zn2+ homeostasis is essential for the central nervous system, in which Zn2+ is abundantly distributed and accumulates in presynaptic vesicles. Synaptic Zn2+ is necessary for neural transmission, playing a pivotal role in neurogenesis, cognition, memory, and learning. Emerging data suggest that disruption of Zn2+ homeostasis is associated with several central nervous system disorders including Alzheimer's disease, depression, Parkinson's disease, multiple sclerosis, schizophrenia, epilepsy, and traumatic brain injury. Here, we reviewed the correlation between Zn2+ and these central nervous system disorders. The potential mechanisms were also included. We hope that this review can provide new clues for the prevention and treatment of nervous system disorders.
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Affiliation(s)
- Bangqi Wang
- Department of Histology and Embryology, Medical College, Nanchang University, Nanchang 330006, China
- Queen Mary School, Medical College, Nanchang University, Nanchang 330006, China
| | - Tianshu Fang
- Department of Histology and Embryology, Medical College, Nanchang University, Nanchang 330006, China
- Queen Mary School, Medical College, Nanchang University, Nanchang 330006, China
| | - Hongping Chen
- Department of Histology and Embryology, Medical College, Nanchang University, Nanchang 330006, China
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12
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Wang K, Shao X, Cai W. Binding Models of Aβ42 Peptide with Membranes Explored by Molecular Simulations. J Chem Inf Model 2022; 62:6482-6493. [PMID: 35984710 DOI: 10.1021/acs.jcim.2c00444] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
One of the factors contributing to the toxicity of amyloid-β (Aβ) peptides is the destruction of membrane integrity through Aβ peptide-membrane interactions. The binding of Aβ peptides to membranes has been studied by experiments and theoretical simulations extensively. The exact binding mechanism, however, still remains elusive. In the present study, the molecular basis of the peptide-bilayer binding mechanism of the full-length Aβ42 monomer with POPC/POPS/CHOL bilayers is investigated by all-atom (AA) simulations. Three main binding models in coil, bend, and turn structures are obtained. Model 1 of the three models with the central hydrophobic core (CHC) buried inside the membrane is the dominant binding model. The structural features of the peptide, the peptide-bilayer interacting regions, the intrapeptide interactions, and peptide-water interactions are studied. The binding of the Aβ42 monomer to the POPC/POPS/CHOL bilayer is also explored by coarse-grained (CG) simulations as a complement. Both the AA and CG simulations show that residues in CHC prefer forming interactions with the bilayer, indicating the crucial role of CHC in peptide-bilayer binding. Our results can provide new insights for the investigation of the peptide-bilayer binding mechanism of the Aβ peptide.
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Affiliation(s)
- Ke Wang
- Research Center for Analytical Sciences, College of Chemistry, Tianjin Key Laboratory of Biosensing and Molecular Recognition, State Key Laboratory of Medicinal Chemical Biology, Nankai University, Tianjin 300071, China.,Haihe Laboratory of Sustainable Chemical Transformations, Tianjin 300192, China
| | - Xueguang Shao
- Research Center for Analytical Sciences, College of Chemistry, Tianjin Key Laboratory of Biosensing and Molecular Recognition, State Key Laboratory of Medicinal Chemical Biology, Nankai University, Tianjin 300071, China.,Haihe Laboratory of Sustainable Chemical Transformations, Tianjin 300192, China
| | - Wensheng Cai
- Research Center for Analytical Sciences, College of Chemistry, Tianjin Key Laboratory of Biosensing and Molecular Recognition, State Key Laboratory of Medicinal Chemical Biology, Nankai University, Tianjin 300071, China.,Haihe Laboratory of Sustainable Chemical Transformations, Tianjin 300192, China
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13
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Zaretsky DV, Zaretskaia MV, Molkov YI. Patients with Alzheimer's disease have an increased removal rate of soluble beta-amyloid-42. PLoS One 2022; 17:e0276933. [PMID: 36315527 PMCID: PMC9621436 DOI: 10.1371/journal.pone.0276933] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2022] [Accepted: 10/17/2022] [Indexed: 11/05/2022] Open
Abstract
Senile plaques, which are mostly composed of beta-amyloid peptide, are the main signature of Alzheimer's disease (AD). Two main forms of beta-amyloid in humans are 40 and 42-amino acid, long; the latter is considered more relevant to AD etiology. The concentration of soluble beta-amyloid-42 (Aβ42) in cerebrospinal fluid (CSF-Aβ42) and the density of amyloid depositions have a strong negative correlation. However, AD patients have lower CSF-Aβ42 levels compared to individuals with normal cognition (NC), even after accounting for this correlation. The goal of this study was to infer deviations of Aβ42 metabolism parameters that underlie this difference using data from the Alzheimer's Disease Neuroimaging Initiative cohort. Aβ42 is released to the interstitial fluid (ISF) by cells and is removed by several processes. First, growth of insoluble fibrils by aggregation decreases the concentration of soluble beta-amyloid in the ISF. Second, Aβ42 is physically transferred from the brain to the CSF and removed with the CSF flow. Finally, there is an intratissue removal of Aβ42 ending in proteolysis, which can occur either in the ISF or inside the cells after the peptide is endocytosed. Unlike aggregation, which preserves the peptide in the brain, transfer to the CSF and intratissue proteolysis together represent amyloid removal. Using a kinetic model of Aβ42 turnover, we found that compared to NC subjects, AD patients had dramatically increased rates of amyloid removal. A group with late-onset mild cognitive impairment (LMCI) also exhibited a higher rate of amyloid removal; however, this was less pronounced than in the AD group. Estimated parameters in the early-onset MCI group did not differ significantly from those in the NC group. We hypothesize that increased amyloid removal is mediated by Aβ42 cellular uptake; this is because CSF flow is not increased in AD patients, while most proteases are intracellular. Aβ cytotoxicity depends on both the amount of beta-amyloid internalized by cells and its intracellular conversion into toxic products. We speculate that AD and LMCI are associated with increased cellular amyloid uptake, which leads to faster disease progression. The early-onset MCI (EMCI) patients do not differ from the NC participants in terms of cellular amyloid uptake. Therefore, EMCI may be mediated by the increased production of toxic amyloid metabolites.
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Affiliation(s)
| | | | - Yaroslav I. Molkov
- Department of Mathematics and Statistics and Neuroscience Institute, Georgia State University, Atlanta, GA, United States of America
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14
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Yan L, Jin Y, Pan J, He X, Zhong S, Zhang R, Choi L, Su W, Chen J. 7,8-Dihydroxycoumarin Alleviates Synaptic Loss by Activated PI3K-Akt-CREB-BDNF Signaling in Alzheimer's Disease Model Mice. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:7130-7138. [PMID: 35657168 PMCID: PMC9204815 DOI: 10.1021/acs.jafc.2c02140] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 05/15/2022] [Accepted: 05/18/2022] [Indexed: 06/15/2023]
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disorder and is clinically characterized by the impairment of memory and cognition. Accumulation of β-amyloid (Aβ) in the brain is considered as a key process in the development of AD because it impairs the synapses' function to impair memory formation. Recent research studies have indicated that a group of edible plant-derived Thymelaeaceae compounds known as coumarin may exert particularly powerful actions on alleviating learning and memory impairment. 7,8-Dithydroxycoumarin (7,8-DHC), a bioactive component of coumarin derived from Thymelaeaceae, showed its function in neuroprotection before. In this study, we found that 7,8-DHC was able to mitigate Aβ accumulation via reducing the level of BACE1 and increasing the level of ADAM17 and ADAM10. More importantly, we found that 7,8-DHC could mitigate memory impairment, promote the dendrite branch density, and increase synaptic protein expression via activating PI3K-Akt-CREB-BDNF signaling. Hence, these results suggested that 7,8-DHC represented a novel bioactive therapeutic agent in mitigating Aβ deposition and synaptic loss in the process of treating AD.
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Affiliation(s)
- Li Yan
- Formula-Pattern
Research Center, School of Traditional Chinese Medicine, Jinan University, Guangzhou 510632, China
| | - Yufan Jin
- Guangdong
Engineering & Technology Research Center for Quality and Efficacy
Reevaluation of Post-Market Traditional Chinese Medicine, Guangdong
Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, No. 135, Xingang Xi Road, Guangzhou 510275, China
| | - Junping Pan
- Department
of Pharmacology, School of Basic Medicine, Jinan University, Guangzhou 510632, China
| | - Xiang He
- Guangdong
Engineering & Technology Research Center for Quality and Efficacy
Reevaluation of Post-Market Traditional Chinese Medicine, Guangdong
Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, No. 135, Xingang Xi Road, Guangzhou 510275, China
| | - Shiqian Zhong
- International
School, Jinan University, No. 601, West Huangpu Avenue, Guangzhou 510632, China
| | - Rongcai Zhang
- International
School, Jinan University, No. 601, West Huangpu Avenue, Guangzhou 510632, China
| | - LokLam Choi
- International
School, Jinan University, No. 601, West Huangpu Avenue, Guangzhou 510632, China
| | - Weiwei Su
- Guangdong
Engineering & Technology Research Center for Quality and Efficacy
Reevaluation of Post-Market Traditional Chinese Medicine, Guangdong
Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, No. 135, Xingang Xi Road, Guangzhou 510275, China
| | - Jiaxu Chen
- Formula-Pattern
Research Center, School of Traditional Chinese Medicine, Jinan University, Guangzhou 510632, China
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15
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Jang H, Park YH, Choe YS, Kang SH, Kang ES, Lee S, Seo SW, Kim HJ, Na DL. Amyloid Positive Hydrocephalus: A Hydrocephalic Variant of Alzheimer's Disease? J Alzheimers Dis 2021; 85:1467-1479. [PMID: 34958024 DOI: 10.3233/jad-215110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Alzheimer's disease (AD) and normal pressure hydrocephalus (NPH) commonly coexist. OBJECTIVE We aimed to characterize an overlapping syndrome of AD and NPH that presents with gait disturbance, ventriculomegaly on magnetic resonance imaging, and significant amyloid deposition on positron emission tomography (PET). METHODS Of 114 patients who underwent cerebrospinal fluid (CSF) drainage for a possible diagnosis of NPH between 2015 and 2020 in Samsung Medical Center, we identified 24 patients (21.1%) with the NPH patients with amyloid deposition on PET, which we referred to as hydrocephalic AD in this study. We compared their clinical and imaging findings with those of 123 typical AD without hydrocephalic signs/symptoms. We also investigated the frequency and potential predictors of the tap test response in hydrocephalic AD. RESULTS Evans' index was 0.36±0.03, and a disproportionately enlarged subarachnoid space was present in 54.2% of the hydrocephalic AD patients. The mean age (75.2±7.3 years) and the APOE4 frequency (68.2%) did not differ from those of AD controls. However, the hydrocephalic AD patients showed better memory and language performance, and a thinner cingulate cortex. About 42% of the hydrocephalic AD patients responded to the tap test, of whom seven underwent shunt surgery. Cognition did not improve, whereas gait improved after shunt surgery in all. CONCLUSION Hydrocephalic AD has different neuropsychological and imaging characteristics from typical AD. Future studies are warranted to further investigate the effect of CSF removal on their clinical course and to elucidate the pathophysiological interaction between amyloid and NPH.
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Affiliation(s)
- Hyemin Jang
- Department of Neurology, Sungkyunkwan University School of Medicine, Seoul, Korea.,Neuroscience Center, Samsung Medical Center, Seoul, Korea.,Samsung Alzheimer Research Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Yu-Hyun Park
- Department of Neurology, Sungkyunkwan University School of Medicine, Seoul, Korea.,Samsung Alzheimer Research Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Young Sim Choe
- Department of Neurology, Sungkyunkwan University School of Medicine, Seoul, Korea.,Samsung Alzheimer Research Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Sung Hoon Kang
- Department of Neurology, Korea University Guro Hospital, Korea University College of Medicine, Seoul, Korea.,Department of Neurology, Sungkyunkwan University School of Medicine, Seoul, Korea.,Neuroscience Center, Samsung Medical Center, Seoul, Korea.,Samsung Alzheimer Research Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Eun-Sook Kang
- Laboratory Medicine and Genetics, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Seunghoon Lee
- Neurosurgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Sang Won Seo
- Department of Neurology, Sungkyunkwan University School of Medicine, Seoul, Korea.,Neuroscience Center, Samsung Medical Center, Seoul, Korea.,Samsung Alzheimer Research Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.,Department of Clinical Research Design & Evaluation, SAIHST, Sungkyunkwan University, Seoul, Korea.,Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, Seoul, Korea
| | - Hee Jin Kim
- Department of Neurology, Sungkyunkwan University School of Medicine, Seoul, Korea.,Neuroscience Center, Samsung Medical Center, Seoul, Korea.,Samsung Alzheimer Research Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Duk L Na
- Department of Neurology, Sungkyunkwan University School of Medicine, Seoul, Korea.,Neuroscience Center, Samsung Medical Center, Seoul, Korea.,Samsung Alzheimer Research Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.,Stem Cell & Regenerative Medicine Institute, Samsung Medical Center, Seoul, South Korea.,Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, Seoul, Korea
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16
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Kim M, Son J, Kim Y. NMR Studies of the Ion Channel-Forming Human Amyloid-β with Zinc Ion Concentrations. MEMBRANES 2021; 11:membranes11110799. [PMID: 34832029 PMCID: PMC8620595 DOI: 10.3390/membranes11110799] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 10/06/2021] [Accepted: 10/14/2021] [Indexed: 11/16/2022]
Abstract
Alzheimer’s disease (AD) is classified as an amyloid-related disease. Amyloid beta (Aβ) is a transmembrane protein known to play a major role in the pathogenesis of AD. These Aβ proteins can form ion channels or pores in the cell membrane. Studies have elucidated the structure of the transmembrane domain of Aβ ion channels. In addition, various studies have investigated substances that block or inhibit the formation of Aβ ion channels. Zinc ions are considered as potential inhibitors of AD. In this study, we focused on the transmembrane domain and some external domains of the Aβ protein (hAPP-TM), and solution-state NMR was used to confirm the effect on residues of the protein in the presence of zinc ions. In addition, we sought to confirm the structure and orientation of the protein in the presence of the bicelle using solid-state NMR.
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Affiliation(s)
| | | | - Yongae Kim
- Correspondence: ; Tel.: +82-31-330-4604; Fax: +82-31-330-4566
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17
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Jadiya P, Garbincius JF, Elrod JW. Reappraisal of metabolic dysfunction in neurodegeneration: Focus on mitochondrial function and calcium signaling. Acta Neuropathol Commun 2021; 9:124. [PMID: 34233766 PMCID: PMC8262011 DOI: 10.1186/s40478-021-01224-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 06/27/2021] [Indexed: 02/06/2023] Open
Abstract
The cellular and molecular mechanisms that drive neurodegeneration remain poorly defined. Recent clinical trial failures, difficult diagnosis, uncertain etiology, and lack of curative therapies prompted us to re-examine other hypotheses of neurodegenerative pathogenesis. Recent reports establish that mitochondrial and calcium dysregulation occur early in many neurodegenerative diseases (NDDs), including Alzheimer's disease, Parkinson's disease, Huntington's disease, and others. However, causal molecular evidence of mitochondrial and metabolic contributions to pathogenesis remains insufficient. Here we summarize the data supporting the hypothesis that mitochondrial and metabolic dysfunction result from diverse etiologies of neuropathology. We provide a current and comprehensive review of the literature and interpret that defective mitochondrial metabolism is upstream and primary to protein aggregation and other dogmatic hypotheses of NDDs. Finally, we identify gaps in knowledge and propose therapeutic modulation of mCa2+ exchange and mitochondrial function to alleviate metabolic impairments and treat NDDs.
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Affiliation(s)
- Pooja Jadiya
- Center for Translational Medicine, Lewis Katz School of Medicine at Temple University, 3500 N Broad St, MERB 949, Philadelphia, PA, 19140, USA
| | - Joanne F Garbincius
- Center for Translational Medicine, Lewis Katz School of Medicine at Temple University, 3500 N Broad St, MERB 949, Philadelphia, PA, 19140, USA
| | - John W Elrod
- Center for Translational Medicine, Lewis Katz School of Medicine at Temple University, 3500 N Broad St, MERB 949, Philadelphia, PA, 19140, USA.
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18
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Zaretsky DV, Zaretskaia MV. Mini-review: Amyloid degradation toxicity hypothesis of Alzheimer's disease. Neurosci Lett 2021; 756:135959. [PMID: 34000347 DOI: 10.1016/j.neulet.2021.135959] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Revised: 04/28/2021] [Accepted: 05/10/2021] [Indexed: 12/21/2022]
Abstract
Alzheimer's disease (AD) is the most common cause of dementia affecting millions of people. Neuronal death in AD is initiated by oligomeric amyloid-β (Aβ) peptides. The amyloid channel hypothesis readily explains the primary molecular damage but does not address major observations associated with AD such as autophagy failure and decreased metabolism. The amyloid degradation toxicity hypothesis provides the interpretation as a sequence of molecular events. Aβ enters a cell by endocytosis, and the endocytic vesicle is merged with a lysosome. Lysosomal peptidases degrade the peptide. Fragments form membrane channels in lysosomal membranes that have a significant negative charge due to the presence of acidic phospholipids. Amyloid channels can transfer various ions (including protons) and even relatively large compounds, which explains lysosomal permeabilization. The neutralization of lysosomal content inactivates degradation enzymes, results in an accumulation of undigested amyloid, and stalls autophagy. Inadequate quality control of mitochondria is associated with an increased production of reactive oxygen species and decreased energy production. Also, the passage of lysosomal proteases through rare extremely large channels results in cell death. Proposed hypothesis identifies biochemical pathways involved in the initiation and progression of cellular damage induced by beta-amyloid and provides new potential pharmacological targets to treat Alzheimer's disease.
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19
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Cascella R, Cecchi C. Calcium Dyshomeostasis in Alzheimer's Disease Pathogenesis. Int J Mol Sci 2021; 22:ijms22094914. [PMID: 34066371 PMCID: PMC8124842 DOI: 10.3390/ijms22094914] [Citation(s) in RCA: 79] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 04/26/2021] [Accepted: 04/30/2021] [Indexed: 01/12/2023] Open
Abstract
Alzheimer’s disease (AD) is the most common age-related neurodegenerative disorder that is characterized by amyloid β-protein deposition in senile plaques, neurofibrillary tangles consisting of abnormally phosphorylated tau protein, and neuronal loss leading to cognitive decline and dementia. Despite extensive research, the exact mechanisms underlying AD remain unknown and effective treatment is not available. Many hypotheses have been proposed to explain AD pathophysiology; however, there is general consensus that the abnormal aggregation of the amyloid β peptide (Aβ) is the initial event triggering a pathogenic cascade of degenerating events in cholinergic neurons. The dysregulation of calcium homeostasis has been studied considerably to clarify the mechanisms of neurodegeneration induced by Aβ. Intracellular calcium acts as a second messenger and plays a key role in the regulation of neuronal functions, such as neural growth and differentiation, action potential, and synaptic plasticity. The calcium hypothesis of AD posits that activation of the amyloidogenic pathway affects neuronal Ca2+ homeostasis and the mechanisms responsible for learning and memory. Aβ can disrupt Ca2+ signaling through several mechanisms, by increasing the influx of Ca2+ from the extracellular space and by activating its release from intracellular stores. Here, we review the different molecular mechanisms and receptors involved in calcium dysregulation in AD and possible therapeutic strategies for improving the treatment.
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20
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Ding Q, Jia Y. Effects of temperature and ion channel blocks on propagation of action potential in myelinated axons. CHAOS (WOODBURY, N.Y.) 2021; 31:053102. [PMID: 34240929 DOI: 10.1063/5.0044874] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 04/14/2021] [Indexed: 06/13/2023]
Abstract
Potassium ion and sodium ion channels play important roles in the propagation of action potentials along a myelinated axon. The random opening and closing of ion channels can cause the fluctuation of action potentials. In this paper, an improved Hodgkin-Huxley chain network model is proposed to study the effects of ion channel blocks, temperature, and ion channel noise on the propagation of action potentials along the myelinated axon. It is found that the chain network has minimum coupling intensity threshold and maximum tolerance temperature threshold that allow the action potentials to pass along the whole axon, and the blockage of ion channels can change these two thresholds. A striking result is that the simulated value of the optimum membrane size (inversely proportional to noise intensity) coincides with the area range of feline thalamocortical relay cells in biological experiments.
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Affiliation(s)
- Qianming Ding
- Department of Physics, Central China Normal University, Wuhan 430079, China
| | - Ya Jia
- Department of Physics, Central China Normal University, Wuhan 430079, China
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21
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Rofo F, Ugur Yilmaz C, Metzendorf N, Gustavsson T, Beretta C, Erlandsson A, Sehlin D, Syvänen S, Nilsson P, Hultqvist G. Enhanced neprilysin-mediated degradation of hippocampal Aβ42 with a somatostatin peptide that enters the brain. Am J Cancer Res 2021; 11:789-804. [PMID: 33391505 PMCID: PMC7738863 DOI: 10.7150/thno.50263] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 10/13/2020] [Indexed: 12/21/2022] Open
Abstract
Background: Aggregation of the amyloid-beta (Aβ) peptide is one of the main neuropathological events in Alzheimer's disease (AD). Neprilysin is the major enzyme degrading Aβ, with its activity enhanced by the neuropeptide somatostatin (SST). SST levels are decreased in the brains of AD patients. The poor delivery of SST over the blood-brain barrier (BBB) and its extremely short half-life of only 3 min limit its therapeutic significance. Methods: We recombinantly fused SST to a BBB transporter binding to the transferrin receptor. Using primary neuronal cultures and neuroblastoma cell lines, the ability of the formed fusion protein to activate neprilysin was studied. SST-scFv8D3 was administered to mice overexpressing the Aβ-precursor protein (AβPP) with the Swedish mutation (APPswe) as a single injection or as a course of three injections over a 72 h period. Levels of neprilysin and Aβ were quantified using an Enzyme-linked immunosorbent assay (ELISA). Distribution of SST-scFv8D3 in the brain, blood and peripheral organs was studied by radiolabeling with iodine-125. Results: The construct, SST-scFv8D3, exhibited 120 times longer half-life than SST alone, reached the brain in high amounts when injected intravenously and significantly increased the brain concentration of neprilysin in APPswe mice. A significant decrease in the levels of membrane-bound Aβ42 was detected in the hippocampus and the adjacent cortical area after only three injections. Conclusion: With intravenous injections of our BBB permeable SST peptide, we were able to significantly increase the levels neprilysin, an effect that was followed by a significant and selective degradation of membrane-bound Aβ42 in the hippocampus. Being that membrane-bound Aβ triggers neuronal toxicity and the hippocampus is the central brain area in the progression of AD, the study has illuminated a new potential treatment paradigm with a promising safety profile targeting only the disease affected areas.
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22
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Wang ZJ, Zhao F, Wang CF, Zhang XM, Xiao Y, Zhou F, Wu MN, Zhang J, Qi JS, Yang W. Xestospongin C, a Reversible IP3 Receptor Antagonist, Alleviates the Cognitive and Pathological Impairments in APP/PS1 Mice of Alzheimer's Disease. J Alzheimers Dis 2020; 72:1217-1231. [PMID: 31683484 DOI: 10.3233/jad-190796] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Exaggerated Ca2+ signaling might be one of primary causes of neural dysfunction in Alzheimer's disease (AD). And the intracellular Ca2+ overload has been closely associated with amyloid-β (Aβ)-induced endoplasmic reticulum (ER) stress and memory impairments in AD. Here we showed for the first time the neuroprotective effects of Xestospongin C (XeC), a reversible IP3 receptor antagonist, on the cognitive behaviors and pathology of APP/PS1 AD mice. Male APP/PS1-AD mice (n = 20) were injected intracerebroventricularly with XeC (3μmol) via Alzet osmotic pumps for four weeks, followed by cognition tests, Aβ plaque examination, and ER stress-related protein measurement. The results showed that XeC pretreatment significantly improved the cognitive behavior of APP/PS1-AD mice, raising the spontaneous alteration accuracy in Y maze, decreasing the escape latency and increasing the target quadrant swimming time in Morris water maze; XeC pretreatment also reduced the number of Aβ plaques and the overexpression of ER stress proteins 78 kDa glucose-regulated protein (GRP-78), caspase-12, and CAAT/enhancer-binding protein (C/EBP) homologous protein (CHOP) in the hippocampus of APP/PS1 mice. In addition, in vitro experiments showed that XeC effectively ameliorated Aβ1 - 42-induced early neuronal apoptosis and intracellular Ca2+ overload in the primary hippocampal neurons. Taken together, IP3R-mediated Ca2+ disorder plays a key role in the cognitive deficits and pathological damages in AD mice. By targeting the IP3 R, XeC might be considered as a novel therapeutic strategy in AD.
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Affiliation(s)
- Zhao-Jun Wang
- Department of Physiology, Key Laboratory of Cellular Physiology, Ministry of Education, Shanxi Medical University, Taiyuan, PR China
| | - Fang Zhao
- Department of Physiology, Key Laboratory of Cellular Physiology, Ministry of Education, Shanxi Medical University, Taiyuan, PR China
| | - Chen-Fang Wang
- Department of Physiology, Key Laboratory of Cellular Physiology, Ministry of Education, Shanxi Medical University, Taiyuan, PR China
| | - Xiu-Min Zhang
- Department of Physiology, Key Laboratory of Cellular Physiology, Ministry of Education, Shanxi Medical University, Taiyuan, PR China
| | - Yi Xiao
- Department of Cardiology, the Third of Kunming People's Hospital, Yunnan, China
| | - Fang Zhou
- Department of Physiology, Key Laboratory of Cellular Physiology, Ministry of Education, Shanxi Medical University, Taiyuan, PR China
| | - Mei-Na Wu
- Department of Physiology, Key Laboratory of Cellular Physiology, Ministry of Education, Shanxi Medical University, Taiyuan, PR China
| | - Jun Zhang
- Department of Physiology, Key Laboratory of Cellular Physiology, Ministry of Education, Shanxi Medical University, Taiyuan, PR China
| | - Jin-Shun Qi
- Department of Physiology, Key Laboratory of Cellular Physiology, Ministry of Education, Shanxi Medical University, Taiyuan, PR China
| | - Wei Yang
- Department of Physiology, Key Laboratory of Cellular Physiology, Ministry of Education, Shanxi Medical University, Taiyuan, PR China
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23
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Zaretsky DV, Zaretskaia MV. Flow cytometry method to quantify the formation of beta-amyloid membrane ion channels. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1863:183506. [PMID: 33171157 DOI: 10.1016/j.bbamem.2020.183506] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Revised: 10/31/2020] [Accepted: 11/05/2020] [Indexed: 11/17/2022]
Abstract
It is accepted that the cytotoxicity of beta-amyloid is mediated by its oligomers. Amyloid peptides can form ion channels in cell membranes and allow calcium and other ions to enter cells. In this project, we developed a technique to quantify the appearance of calcium in liposomes and applied this technique to study the effect of amyloid peptides on the permeability of membranes. Calcium influx was monitored in liposomes made of phosphatidylcholine (PC) or phosphatidylserine (PS) with an addition of a lipid-soluble dye DiD and containing fluorescent calcium-sensitive probe Fluo-3. The intensity of fluorescence of individual liposomes was measured using a flow cytometer. Calcium ionophore ionomycin served as a positive control. The addition of micromolar concentrations of short fragments of amyloid-beta (Aβ25-35) permeabilized a significant number of PS liposomes. This effect was not observed in PC liposomes. Our data supports the hypothesis that the ion channel formation by amyloid peptide is dependent on electrostatic interactions. High concentrations of Aβ25-35 (above 20 μM) increased signal intensity in a recording channel corresponding to the calcium-sensing probe. However, this phenomenon was also observed in Ca2+-free conditions and even in liposomes without Fluo-3, so we interpreted it as an artifact. Using the described technique, we were not able to detect the formation of calcium channels by several other amyloid peptides. Considering that liposomes appeared resistant to reasonable concentrations of solvents, we expect that described flowmetric technique can be used in high-throughput screening applications.
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24
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Stoye NM, Dos Santos Guilherme M, Endres K. Alzheimer's disease in the gut-Major changes in the gut of 5xFAD model mice with ApoA1 as potential key player. FASEB J 2020; 34:11883-11899. [PMID: 32681583 DOI: 10.1096/fj.201903128rr] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 06/17/2020] [Accepted: 06/23/2020] [Indexed: 12/12/2022]
Abstract
Alzheimer's disease (AD) affects around 33 million people worldwide, which makes it the most prominent form of dementia. The main focus of AD research has been on the central nervous system (CNS) for long, but in recent years, the gut gained more attention. The intestinal tract is innervated by the enteric nervous system (ENS), built of numerous different types of neurons showing great similarity to neurons of the CNS. It already has been demonstrated that the amyloid precursor protein, which plays a major role in AD pathology, is also expressed in these cells. We analyzed gut tissue of AD model mice (5xFAD) and the respective wild-type littermates at different pathological stages: pre-pathological, early pathological and late pathological. Our results show significant difference in function of the intestine of 5xFAD mice as compared to wild-type mice. Using a pathway array detecting 84 AD-related gene products, we found ApoA1 expression significantly altered in colon tissue of 5xFAD mice. Furthermore, we unveil ApoA1's beneficial impact on cell viability and calcium homeostasis of cultured enteric neurons of 5xFAD animals. With this study, we demonstrate that the intestine is altered in AD-like pathology and that ApoA1 might be one key player within the gut.
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Affiliation(s)
- Nicolai M Stoye
- Department of Psychiatry and Psychotherapy, University Medical Center of the Johannes Gutenberg-University, Mainz, Germany
| | - Malena Dos Santos Guilherme
- Department of Psychiatry and Psychotherapy, University Medical Center of the Johannes Gutenberg-University, Mainz, Germany
| | - Kristina Endres
- Department of Psychiatry and Psychotherapy, University Medical Center of the Johannes Gutenberg-University, Mainz, Germany
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25
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Majdi A, Sadigh-Eteghad S, Rahigh Aghsan S, Farajdokht F, Vatandoust SM, Namvaran A, Mahmoudi J. Amyloid-β, tau, and the cholinergic system in Alzheimer's disease: seeking direction in a tangle of clues. Rev Neurosci 2020; 31:391-413. [PMID: 32017704 DOI: 10.1515/revneuro-2019-0089] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 12/22/2019] [Indexed: 12/14/2022]
Abstract
The link between histopathological hallmarks of Alzheimer's disease (AD), i.e. amyloid plaques, and neurofibrillary tangles, and AD-associated cognitive impairment, has long been established. However, the introduction of interactions between amyloid-beta (Aβ) as well as hyperphosphorylated tau, and the cholinergic system to the territory of descriptive neuropathology has drastically changed this field by adding the theory of synaptic neurotransmission to the toxic pas de deux in AD. Accumulating data show that a multitarget approach involving all amyloid, tau, and cholinergic hypotheses could better explain the evolution of events happening in AD. Various species of both Aβ and tau could be traced in cholinergic neurons of the basal forebrain system early in the course of the disease. These molecules induce degeneration in the neurons of this system. Reciprocally, aberrant cholinergic system modulation promotes changes in amyloid precursor protein (APP) metabolism and tau phosphorylation, resulting in neurotoxicity, neuroinflammation, and neuronal death. Altogether, these changes may better correlate with the clinical findings and cognitive impairment detected in AD patients. Failure of several of Aβ- and tau-related therapies further highlights the need for special attention to molecules that target all of these mentioned pathologic changes. Another noteworthy fact here is that none of the popular hypotheses of AD such as amyloidopathy or tauopathy seem to be responsible for the changes observed in AD alone. Thus, the main culprit should be sought higher in the stream somewhere in APP metabolism or Wnt signaling in the cholinergic system of the basal forebrain. Future studies should target these pathological events.
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Affiliation(s)
- Alireza Majdi
- Neurosciences Research Center (NSRC), Tabriz University of Medical Sciences, Tabriz 51368, Iran
| | - Saeed Sadigh-Eteghad
- Neurosciences Research Center (NSRC), Tabriz University of Medical Sciences, Tabriz 51368, Iran
| | - Sepideh Rahigh Aghsan
- Department of Clinical Pharmacy, Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz 51368, Iran
| | - Fereshteh Farajdokht
- Neurosciences Research Center (NSRC), Tabriz University of Medical Sciences, Tabriz 51368, Iran
| | - Seyed Mehdi Vatandoust
- Neurosciences Research Center (NSRC), Tabriz University of Medical Sciences, Tabriz 51368, Iran
| | - Ali Namvaran
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz 51368, Iran
| | - Javad Mahmoudi
- Neurosciences Research Center (NSRC), Tabriz University of Medical Sciences, Tabriz 51368, Iran
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26
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Kawahara M, Kato-Negishi M, Tanaka KI. Amyloids: Regulators of Metal Homeostasis in the Synapse. Molecules 2020; 25:molecules25061441. [PMID: 32210005 PMCID: PMC7145306 DOI: 10.3390/molecules25061441] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 03/17/2020] [Accepted: 03/20/2020] [Indexed: 12/11/2022] Open
Abstract
Conformational changes in amyloidogenic proteins, such as β-amyloid protein, prion proteins, and α-synuclein, play a critical role in the pathogenesis of numerous neurodegenerative diseases, including Alzheimer’s disease, prion disease, and Lewy body disease. The disease-associated proteins possess several common characteristics, including the ability to form amyloid oligomers with β-pleated sheet structure, as well as cytotoxicity, although they differ in amino acid sequence. Interestingly, these amyloidogenic proteins all possess the ability to bind trace metals, can regulate metal homeostasis, and are co-localized at the synapse, where metals are abundantly present. In this review, we discuss the physiological roles of these amyloidogenic proteins in metal homeostasis, and we propose hypothetical models of their pathogenetic role in the neurodegenerative process as the loss of normal metal regulatory functions of amyloidogenic proteins. Notably, these amyloidogenic proteins have the capacity to form Ca2+-permeable pores in membranes, suggestive of a toxic gain of function. Therefore, we focus on their potential role in the disruption of Ca2+ homeostasis in amyloid-associated neurodegenerative diseases.
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27
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Pannaccione A, Piccialli I, Secondo A, Ciccone R, Molinaro P, Boscia F, Annunziato L. The Na +/Ca 2+exchanger in Alzheimer's disease. Cell Calcium 2020; 87:102190. [PMID: 32199208 DOI: 10.1016/j.ceca.2020.102190] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 02/26/2020] [Accepted: 03/01/2020] [Indexed: 12/19/2022]
Abstract
As a pivotal player in regulating sodium (Na+) and calcium (Ca2+) homeostasis and signalling in excitable cells, the Na+/Ca2+ exchanger (NCX) is involved in many neurodegenerative disorders in which an imbalance of intracellular Ca2+ and/or Na+ concentrations occurs, including Alzheimer's disease (AD). Although NCX has been mainly implicated in neuroprotective mechanisms counteracting Ca2+ dysregulation, several studies highlighted its role in the neuronal responses to intracellular Na+ elevation occurring in several pathophysiological conditions. Since the alteration of Na+ and Ca2+ homeostasis significantly contributes to synaptic dysfunction and neuronal loss in AD, it is of crucial importance to analyze the contribution of NCX isoforms in the homeostatic responses at neuronal and synaptic levels. Some studies found that an increase of NCX activity in brains of AD patients was correlated with neuronal survival, while other research groups found that protein levels of two NCX subtypes, NCX2 and NCX3, were modulated in parietal cortex of late stage AD brains. In particular, NCX2 positive synaptic terminals were increased in AD cohort while the number of NCX3 positive terminals were reduced. In addition, NCX1, NCX2 and NCX3 isoforms were up-regulated in those synaptic terminals accumulating amyloid-beta (Aβ), the neurotoxic peptide responsible for AD neurodegeneration. More recently, the hyperfunction of a specific NCX subtype, NCX3, has been shown to delay endoplasmic reticulum stress and apoptotic neuronal death in hippocampal neurons exposed to Aβ insult. Despite some issues about the functional role of NCX in synaptic failure and neuronal loss require further studies, these findings highlight the putative neuroprotective role of NCX in AD and open new strategies to develop new druggable targets for AD therapy.
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Affiliation(s)
- Anna Pannaccione
- Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, Federico II University of Naples, Via Pansini, 5, 80131, Naples, Italy.
| | - Ilaria Piccialli
- Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, Federico II University of Naples, Via Pansini, 5, 80131, Naples, Italy
| | - Agnese Secondo
- Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, Federico II University of Naples, Via Pansini, 5, 80131, Naples, Italy
| | - Roselia Ciccone
- Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, Federico II University of Naples, Via Pansini, 5, 80131, Naples, Italy
| | - Pasquale Molinaro
- Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, Federico II University of Naples, Via Pansini, 5, 80131, Naples, Italy
| | - Francesca Boscia
- Division of Pharmacology, Department of Neuroscience, Reproductive and Dentistry Sciences, School of Medicine, Federico II University of Naples, Via Pansini, 5, 80131, Naples, Italy
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Doens D, Valdés-Tresanco ME, Vasquez V, Carreira MB, De La Guardia Y, Stephens DE, Nguyen VD, Nguyen VT, Gu J, Hegde ML, Larionov OV, Valiente PA, Lleonart R, Fernández PL. Hexahydropyrrolo[2,3- b]indole Compounds as Potential Therapeutics for Alzheimer's Disease. ACS Chem Neurosci 2019; 10:4250-4263. [PMID: 31545596 DOI: 10.1021/acschemneuro.9b00297] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Alzheimer's disease (AD) is the most common form of dementia among the elderly and has become a leading public health concern worldwide. It represents a huge economic and psychological burden to caregivers and families. The presence of extracellular amyloid beta (Aβ) plaques is one of the hallmarks of this neurodegenerative disorder. Amyloid plaques are comprised of aggregates of Aβ peptides, mainly Aβ42, originated by the cleavage of the amyloid precursor protein (APP). Aβ is a crucial target for the treatment of AD, but to date, no effective treatment for the clearance of Aβ has been found. We have identified four new hexahydropyrroloindoles (HPI) synthetic compounds that are able to inhibit the aggregation of Aβ42 and/or disaggregate the fibril. Docking experiments suggest that the nonpolar component of the interaction of compounds with Aβ42 contributes favorably to the binding free energy of each complex. Molecular dynamics simulations suggested fibril disaggregating activity of compounds 1 via interaction with hydrophobic moieties of the fibril. Consistently, compounds 1 and 2 were able to mitigate Aβ42 fibrils induced death in rat pheochromocytoma cells (PC 12). One of the compounds reduces the formation of Aβ aggregates in vivo and the paralysis associated with Aβ toxicity in Caenorhabditis elegans. Our study thus augments efforts for the identification and characterization of new agents that may help stop or delay the progression of AD.
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Affiliation(s)
- Deborah Doens
- Centro de Biología Celular y Molecular de Enfermedades, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología (INDICASAT-AIP), City of Knowledge Edif #208, Panama 0843-01103, Panama
- Department of Biotechnology, Acharya Nagarjuna University, Nagarjuna Nagar, Guntur, Andhra Pradesh 522510, India
| | - Mario E. Valdés-Tresanco
- Centro de Estudios de Proteínas, Facultad de Biología, Universidad de La Habana, Calle 25 No. 455, Vedado, La Habana, Cuba
| | - Velmarini Vasquez
- Department of Biotechnology, Acharya Nagarjuna University, Nagarjuna Nagar, Guntur, Andhra Pradesh 522510, India
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston, Texas 77030, United States
| | - Maria Beatriz Carreira
- Centro de Neurociencias, INDICASAT-AIP, City of Knowledge Edif #208, Panama, 0843-01103, Panama
| | - Yila De La Guardia
- Centro de Biología Celular y Molecular de Enfermedades, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología (INDICASAT-AIP), City of Knowledge Edif #208, Panama 0843-01103, Panama
| | - David E. Stephens
- Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249, United States
| | - Viet D. Nguyen
- Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249, United States
| | - Vu T. Nguyen
- Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249, United States
| | - Jianhua Gu
- AFM SEM Core, Houston Methodist Research Institute, Houston, Texas 77030, United States
| | - Muralidhar L. Hegde
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston, Texas 77030, United States
| | - Oleg V. Larionov
- Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249, United States
| | - Pedro A. Valiente
- Centro de Estudios de Proteínas, Facultad de Biología, Universidad de La Habana, Calle 25 No. 455, Vedado, La Habana, Cuba
| | - Ricardo Lleonart
- Centro de Biología Celular y Molecular de Enfermedades, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología (INDICASAT-AIP), City of Knowledge Edif #208, Panama 0843-01103, Panama
| | - Patricia L. Fernández
- Centro de Biología Celular y Molecular de Enfermedades, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología (INDICASAT-AIP), City of Knowledge Edif #208, Panama 0843-01103, Panama
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Arispe N, De Maio A. Memory Loss and the Onset of Alzheimer's Disease Could Be Under the Control of Extracellular Heat Shock Proteins. J Alzheimers Dis 2019; 63:927-934. [PMID: 29689729 DOI: 10.3233/jad-180161] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Alzheimer's disease (AD) is a major contemporary and escalating malady in which amyloid-β (Aβ) peptides are the most likely causative agent. Aβ peptides spontaneously tend to aggregate in extracellular fluids following a progression from a monomeric state, through intermediate forms, ending in amyloid fibers and plaques. It is generally accepted now that the neurotoxic agents leading to cellular death, memory loss, and other AD characteristics are the Aβ intermediate aggregated states. However, Aβ peptides are continuously produced, released into the extracellular space, and rapidly cleared from healthy brains. Coincidentally, members of the heat shock proteins (hsp) family are present in the extracellular medium of healthy cells and body fluids, opening the possibility that hsps and Aβ could meet and interact in the extracellular milieu of the brain. In this perspective and reflection article, we place our investigation showing that the presence of Hsp70s mitigate the formation of low molecular weight Aβ peptide oligomers resulting in a reduction of cellular toxicity, in context of the current understanding of the disease. We propose that it may be an inverse relationship between the presence of Hsp70, the stage of Aβ oligomers, neurotoxicity, and the incidence of AD, particularly since the expression and circulating levels of hsp decrease with aging. Combining these observations, we propose that changes in the dynamics of Hsp70s and Aβ concentrations in the circulating brain fluids during aging defines the control of the formation of Aβ toxic aggregates, thus determining the conditions for neuron degeneration and the incidence of AD.
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Affiliation(s)
- Nelson Arispe
- Department of Anatomy, Physiology and Genetics, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
| | - Antonio De Maio
- Department of Surgery and Neurosciences, University of California, San Diego, School of Medicine, La Jolla, CA, USA
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Zhang X, Zhu C, Beecham G, Vardarajan BN, Ma Y, Lancour D, Farrell JJ, Chung J, Mayeux R, Haines JL, Schellenberg GD, Pericak-Vance MA, Lunetta KL, Farrer LA. A rare missense variant of CASP7 is associated with familial late-onset Alzheimer's disease. Alzheimers Dement 2019; 15:441-452. [PMID: 30503768 PMCID: PMC6408965 DOI: 10.1016/j.jalz.2018.10.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Revised: 10/04/2018] [Accepted: 10/11/2018] [Indexed: 12/21/2022]
Abstract
INTRODUCTION The genetic architecture of Alzheimer's disease (AD) is only partially understood. METHODS We conducted an association study for AD using whole sequence data from 507 genetically enriched AD cases (i.e., cases having close relatives affected by AD) and 4917 cognitively healthy controls of European ancestry (EA) and 172 enriched cases and 179 controls of Caribbean Hispanic ancestry. Confirmation of top findings from stage 1 was sought in two family-based genome-wide association study data sets and in a whole genome-sequencing data set comprising members from 42 EA and 115 Caribbean Hispanic families. RESULTS We identified associations in EAs with variants in 12 novel loci. The most robust finding is a rare CASP7 missense variant (rs116437863; P = 2.44 × 10-10) which improved when combined with results from stage 2 data sets (P = 1.92 × 10-10). DISCUSSION Our study demonstrated that an enriched case design can strengthen genetic signals, thus allowing detection of associations that would otherwise be missed in a traditional case-control study.
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Affiliation(s)
- Xiaoling Zhang
- Department of Medicine (Biomedical Genetics), Boston University School of Medicine, Boston, MA, USA; Department of Biostatistics, Boston University School of Public Health, Boston, MA, USA
| | - Congcong Zhu
- Department of Medicine (Biomedical Genetics), Boston University School of Medicine, Boston, MA, USA
| | - Gary Beecham
- Hussman Institute of Human Genetics, University of Miami, Miami, FL, USA
| | | | - Yiyi Ma
- Department of Medicine (Biomedical Genetics), Boston University School of Medicine, Boston, MA, USA
| | - Daniel Lancour
- Department of Medicine (Biomedical Genetics), Boston University School of Medicine, Boston, MA, USA
| | - John J Farrell
- Department of Medicine (Biomedical Genetics), Boston University School of Medicine, Boston, MA, USA
| | - Jaeyoon Chung
- Department of Medicine (Biomedical Genetics), Boston University School of Medicine, Boston, MA, USA
| | - Richard Mayeux
- Department of Neurology, Columbia University, New York, NY, USA
| | - Jonathan L Haines
- Department of Epidemiology and Biostatistics, Case Western Reserve University, Cleveland, OH, USA
| | - Gerard D Schellenberg
- Department of Pathology and Laboratory Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | | | - Kathryn L Lunetta
- Department of Biostatistics, Boston University School of Public Health, Boston, MA, USA
| | - Lindsay A Farrer
- Department of Medicine (Biomedical Genetics), Boston University School of Medicine, Boston, MA, USA; Department of Biostatistics, Boston University School of Public Health, Boston, MA, USA; Department of Neurology, Boston University School of Medicine, Boston, MA, USA; Department of Ophthalmology, Boston University School of Medicine, Boston, MA, USA; Department of Epidemiology, Boston University School of Public Health, Boston, MA, USA.
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31
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Abstract
Aβ accumulation has been discovered to form large, relatively cation-permeable channels in the plasma membrane of a neuron. These channel formations in the membranes of a neuron could cause cell depolarisation, sodium and potassium dysregulation, depletion of neural energy stores and other types of cellular dysfunction. This study shows that the build-up of amyloid beta (Aβ) depositions during the onset of Alzheimer’s disease has profound effects on the activity of the local community of neurons in the central nervous system. These effects can include enhanced neural activity, spontaneous epileptiform activity and incidence of epileptic seizures. From the results in this area, it can be seen that the neurodegeneration observed in Alzheimer’s disease has been associated with the increase of toxicity of Aβ depositions. In this research paper, we examined this hypothesis in light of a computational model of a neuron.
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Fülöp T, Itzhaki RF, Balin BJ, Miklossy J, Barron AE. Role of Microbes in the Development of Alzheimer's Disease: State of the Art - An International Symposium Presented at the 2017 IAGG Congress in San Francisco. Front Genet 2018; 9:362. [PMID: 30250480 PMCID: PMC6139345 DOI: 10.3389/fgene.2018.00362] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Accepted: 08/21/2018] [Indexed: 12/17/2022] Open
Abstract
This article reviews research results and ideas presented at a special symposium at the International Association of Gerontology and Geriatrics (IAGG) Congress held in July 2017 in San Francisco. Five researchers presented their results related to infection and Alzheimer's disease (AD). Prof. Itzhaki presented her work on the role of viruses, specifically HSV-1, in the pathogenesis of AD. She maintains that although it is true that most people harbor HSV-1 infection, either latent or active, nonetheless aspects of herpes infection can play a role in the pathogenesis of AD, based on extensive experimental evidence from AD brains and infected cell cultures. Dr. Miklossy presented research on the high prevalence of bacterial infections that correlate with AD, specifically spirochete infections, which have been known for a century to be a significant cause of dementia (e.g., in syphilis). She demonstrated how spirochetes drive senile plaque formation, which are in fact biofilms. Prof. Balin then described the involvement of brain tissue infection by the Chlamydia pneumoniae bacterium, with its potential to use the innate immune system in its spread, and its initiation of tissue damage characteristic of AD. Prof. Fülöp described the role of AD-associated amyloid beta (Aβ) peptide as an antibacterial, antifungal and antiviral innate immune effector produced in reaction to microorganisms that attack the brain. Prof. Barron put forward the novel hypothesis that, according to her experiments, there is strong sequence-specific binding between the AD-associated Aβ and another ubiquitous and important human innate immune effector, the cathelicidin peptide LL-37. Given this binding, LL-37 expression in the brain will decrease Aβ deposition via formation of non-toxic, soluble Aβ/LL-37 complexes. Therefore, a chronic underexpression of LL-37 could be the factor that simultaneously permits chronic infections in brain tissue and allows for pathological accumulation of Aβ. This first-of-its-kind symposium opened the way for a paradigm shift in studying the pathogenesis of AD, from the "amyloid cascade hypothesis," which so far has been quite unsuccessful, to a new "infection hypothesis," or perhaps more broadly, "innate immune system dysregulation hypothesis," which may well permit and lead to the discovery of new treatments for AD patients.
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Affiliation(s)
- Tamàs Fülöp
- Department of Medicine, Division of Geriatrics, Research Center on Aging, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Ruth F. Itzhaki
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Brian J. Balin
- Department of Bio-Medical Sciences, Center for Chronic Disorders of Aging, Philadelphia College of Osteopathic Medicine, Philadelphia, PA, United States
| | - Judith Miklossy
- International Alzheimer Research Centre, Prevention Alzheimer International Foundation, Martigny-Croix, Switzerland
| | - Annelise E. Barron
- Department of Bioengineering, Stanford University, Stanford, CA, United States
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Fernández-Pérez EJ, Sepúlveda FJ, Peters C, Bascuñán D, Riffo-Lepe NO, González-Sanmiguel J, Sánchez SA, Peoples RW, Vicente B, Aguayo LG. Effect of Cholesterol on Membrane Fluidity and Association of Aβ Oligomers and Subsequent Neuronal Damage: A Double-Edged Sword. Front Aging Neurosci 2018; 10:226. [PMID: 30123122 PMCID: PMC6085471 DOI: 10.3389/fnagi.2018.00226] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Accepted: 07/03/2018] [Indexed: 02/06/2023] Open
Abstract
Background: The beta-amyloid peptide (Aβ) involved in Alzheimer's disease (AD) has been described to associate/aggregate on the cell surface disrupting the membrane through pore formation and breakage. However, molecular determinants involved for this interaction (e.g., some physicochemical properties of the cell membrane) are largely unknown. Since cholesterol is an important molecule for membrane structure and fluidity, we examined the effect of varying cholesterol content with the association and membrane perforation by Aβ in cultured hippocampal neurons. Methods: To decrease or increase the levels of cholesterol in the membrane we used methyl-β-cyclodextrin (MβCD) and MβCD/cholesterol, respectively. We analyzed if membrane fluidity was affected using generalized polarization (GP) imaging and the fluorescent dye di-4-ANEPPDHQ. Additionally membrane association and perforation was assessed using immunocytochemistry and electrophysiological techniques, respectively. Results: The results showed that cholesterol removal decreased the macroscopic association of Aβ to neuronal membranes (fluorescent-puncta/20 μm: control = 18 ± 2 vs. MβCD = 10 ± 1, p < 0.05) and induced a facilitation of the membrane perforation by Aβ with respect to control cells (half-time for maximal charge transferred: control = 7.2 vs. MβCD = 4.4). Under this condition, we found an increase in membrane fluidity (46 ± 3.3% decrease in GP value, p < 0.001). On the contrary, increasing cholesterol levels incremented membrane rigidity (38 ± 2.7% increase in GP value, p < 0.001) and enhanced the association and clustering of Aβ (fluorescent-puncta/20 μm: control = 18 ± 2 vs. MβCD = 10 ± 1, p < 0.01), but inhibited membrane disruption. Conclusion: Our results strongly support the significance of plasma membrane organization in the toxic effects of Aβ in hippocampal neurons, since fluidity can regulate distribution and insertion of the Aβ peptide in the neuronal membrane.
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Affiliation(s)
- Eduardo J Fernández-Pérez
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
| | - Fernando J Sepúlveda
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
| | - Christian Peters
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
| | - Denisse Bascuñán
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
| | - Nicolás O Riffo-Lepe
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
| | | | - Susana A Sánchez
- Departamento de Polímeros, Facultad de Ciencias Químicas, Universidad de Concepción, Concepción, Chile
| | - Robert W Peoples
- Department of Biomedical Sciences, Marquette University, Milwaukee, WI, United States
| | - Benjamín Vicente
- Department of Psychiatry and Mental Health, Universidad de Concepción, Concepción, Chile
| | - Luis G Aguayo
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
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Choi H, Yoon T, Na S. Length-Dependent Manifestation of Vibration Modes Regulates a Specific Intermediate Morphology of Aβ17-42 in Different Environments. Chemphyschem 2018; 19:1643-1654. [PMID: 29575445 DOI: 10.1002/cphc.201800010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Indexed: 12/25/2022]
Abstract
Various cytotoxic mechanisms for neurodegenerative disease are induced by specific conformations of Aβ intermediates. The efforts to understand the diverse intermediate forms of amyloid oligomers have been focused on understanding the aggregation mechanism of specific morphologies for Aβ intermediates. However, these are still not easy tasks to be accomplished because the diverse conformations of Aβ intermediates can be altered during the aggregation process, even though the same Aβ monomers are present. Thus, efforts to reveal the conformational change mechanism could be a fundamental process to understand the formation of diverse Aβ intermediate conformations. Here, we evaluate the conformational characteristics of Aβ17-42 fibrillar oligomers in different environments according to the length. We observed that Aβ fibrillar oligomers optimize their inherent hydrogen bonds and configurational entropy to stabilize their structure according to the simulation time and their length increase. In addition, we revealed the role of the expressed vibration mode shape in the fibrillar oligomers' elongation and deformation processes. Our results suggest that limitations in amyloid oligomer growth and transformations of their morphologies can be regulated and controlled by modifying the vibration features.
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Affiliation(s)
- Hyunsung Choi
- Department of Mechanical Engineering, Korea University, Seoul, 02841, Republic of Korea
| | - Taeyoung Yoon
- Department of Mechanical Engineering, Korea University, Seoul, 02841, Republic of Korea
| | - Sungsoo Na
- Department of Mechanical Engineering, Korea University, Seoul, 02841, Republic of Korea
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Cascella R, Evangelisti E, Bigi A, Becatti M, Fiorillo C, Stefani M, Chiti F, Cecchi C. Soluble Oligomers Require a Ganglioside to Trigger Neuronal Calcium Overload. J Alzheimers Dis 2018; 60:923-938. [PMID: 28922156 DOI: 10.3233/jad-170340] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
An altered distribution of membrane gangliosides (GM), including GM1, has recently been reported in the brains of Alzheimer's disease (AD) patients. Moreover, amyloid-positive synaptosomes obtained from AD brains were found to contain high-density GM1 clusters, suggesting a pathological significance of GM1 increase at presynaptic neuritic terminals in AD. Here, we show that membrane GM1 specifically recruits small soluble oligomers of the 42-residue form of amyloid-β peptide (Aβ42), with intracellular flux of Ca2+ ions in primary rat hippocampal neurons and in human neuroblastoma cells. Specific membrane proteins appear to be involved in the early and transient influx of Ca2+ ions induced by Aβ42 oligomers with high solvent-exposed hydrophobicity (A+), but not in the sustained late influx of the same oligomers and in that induced by Aβ42 oligomers with low solvent-exposed hydrophobicity (A-) in GM1-enriched cells. In addition, A+ oligomers accumulate in proximity of membrane NMDA and AMPA receptors, inducing the early and transient Ca2+ influx, although FRET shows that the interaction is not direct. These results suggest that age-dependent clustering of GM1 within neuronal membranes could induce neurodegeneration in elderly people as a consequence of an increased ability of the lipid bilayers to recruit membrane-permeabilizing oligomers. We also show that both lipid and protein components of the plasma membrane can contribute to neuronal dysfunction, thus expanding the molecular targets for therapeutic intervention in AD.
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Affiliation(s)
- Roberta Cascella
- Department of Experimental and Clinical Biomedical Sciences, University of Florence, Florence, Italy
| | - Elisa Evangelisti
- Department of Experimental and Clinical Biomedical Sciences, University of Florence, Florence, Italy
| | - Alessandra Bigi
- Department of Experimental and Clinical Biomedical Sciences, University of Florence, Florence, Italy
| | - Matteo Becatti
- Department of Experimental and Clinical Biomedical Sciences, University of Florence, Florence, Italy
| | - Claudia Fiorillo
- Department of Experimental and Clinical Biomedical Sciences, University of Florence, Florence, Italy
| | - Massimo Stefani
- Department of Experimental and Clinical Biomedical Sciences, University of Florence, Florence, Italy
| | - Fabrizio Chiti
- Department of Experimental and Clinical Biomedical Sciences, University of Florence, Florence, Italy
| | - Cristina Cecchi
- Department of Experimental and Clinical Biomedical Sciences, University of Florence, Florence, Italy
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Smith AK, Klimov DK. Binding of Cytotoxic Aβ25–35 Peptide to the Dimyristoylphosphatidylcholine Lipid Bilayer. J Chem Inf Model 2018; 58:1053-1065. [DOI: 10.1021/acs.jcim.8b00045] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Amy K. Smith
- School of Systems Biology, George Mason University, Manassas, Virginia 20110, United States
| | - Dmitri K. Klimov
- School of Systems Biology, George Mason University, Manassas, Virginia 20110, United States
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37
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Ge X, Sun Y, Ding F. Structures and dynamics of β-barrel oligomer intermediates of amyloid-beta16-22 aggregation. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1860:1687-1697. [PMID: 29550287 DOI: 10.1016/j.bbamem.2018.03.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Revised: 03/06/2018] [Accepted: 03/07/2018] [Indexed: 01/13/2023]
Abstract
Accumulating evidence suggests that soluble oligomers are more toxic than final fibrils of amyloid aggregations. Among the mixture of inter-converting intermediates with continuous distribution of sizes and secondary structures, oligomers in the β-barrel conformation - a common class of protein folds with a closed β-sheet - have been postulated as the toxic species with well-defined three-dimensional structures to perform pathological functions. A common mechanism for amyloid toxicity, therefore, implies that all amyloid peptides should be able to form β-barrel oligomers as the aggregation intermediates. Here, we applied all-atom discrete molecular dynamics (DMD) simulations to evaluate the formation of β-barrel oligomers and characterize their structures and dynamics in the aggregation of a seven-residue amyloid peptide, corresponding to the amyloid core of amyloid-β with a sequence of 16KLVFFAE22 (Aβ16-22). We carried out aggregation simulations with various numbers of peptides to study the size dependence of aggregation dynamics and assembly structures. Consistent with previous computational studies, we observed the formation of β-barrel oligomers in all-atom DMD simulations. Using a network-based approach to automatically identify β-barrel conformations, we systematically characterized β-barrels of various sizes. Our simulations revealed the conformational inter-conversion between β-barrels and double-layer β-sheets due to increased structural strains upon forming a closed β-barrel while maximizing backbone hydrogen bonds. The potential of mean force analysis further characterized the free energy barriers between these two states. The obtained structural and dynamic insights of β-barrel oligomers may help better understand the molecular mechanism of oligomer toxicities and design novel therapeutics targeting the toxic β-barrel oligomers. This article is part of a Special Issue entitled: Protein Aggregation and Misfolding at the Cell Membrane Interface edited by Ayyalusamy Ramamoorthy.
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Affiliation(s)
- Xinwei Ge
- Department of Physics and Astronomy, Clemson University, Clemson, SC 29634, United States
| | - Yunxiang Sun
- Department of Physics and Astronomy, Clemson University, Clemson, SC 29634, United States
| | - Feng Ding
- Department of Physics and Astronomy, Clemson University, Clemson, SC 29634, United States.
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Pchitskaya E, Popugaeva E, Bezprozvanny I. Calcium signaling and molecular mechanisms underlying neurodegenerative diseases. Cell Calcium 2018; 70:87-94. [PMID: 28728834 PMCID: PMC5748019 DOI: 10.1016/j.ceca.2017.06.008] [Citation(s) in RCA: 199] [Impact Index Per Article: 33.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 06/22/2017] [Accepted: 06/22/2017] [Indexed: 01/23/2023]
Abstract
Calcium (Ca2+) is a ubiquitous second messenger that regulates various activities in eukaryotic cells. Especially important role calcium plays in excitable cells. Neurons require extremely precise spatial-temporal control of calcium-dependent processes because they regulate such vital functions as synaptic plasticity. Recent evidence indicates that neuronal calcium signaling is abnormal in many of neurodegenerative disorders such as Alzheimer's disease (AD), Huntington's disease (HD) and Parkinson's disease (PD). These diseases represent a major medical, social, financial and scientific problem, but despite enormous research efforts, they are still incurable and only symptomatic relief drugs are available. Thus, new approaches and targets are needed. This review highlight neuronal calcium-signaling abnormalities in these diseases, with particular emphasis on the role of neuronal store-operated Ca2+ entry (SOCE) pathway and its potential relevance as a therapeutic target for treatment of neurodegeneration.
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Affiliation(s)
- Ekaterina Pchitskaya
- Laboratory of Molecular Neurodegeneration, Department of Medical Physics, Peter The Great St. Petersburg Polytechnic University, St. Petersburg, Russian Federation.
| | - Elena Popugaeva
- Laboratory of Molecular Neurodegeneration, Department of Medical Physics, Peter The Great St. Petersburg Polytechnic University, St. Petersburg, Russian Federation.
| | - Ilya Bezprozvanny
- Laboratory of Molecular Neurodegeneration, Department of Medical Physics, Peter The Great St. Petersburg Polytechnic University, St. Petersburg, Russian Federation; Department of Physiology, UT Southwestern Medical Center at Dallas, Dallas, TX, USA.
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Effects of ion channel blocks on electrical activity of stochastic Hodgkin–Huxley neural network under electromagnetic induction. Neurocomputing 2018. [DOI: 10.1016/j.neucom.2017.12.036] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Rivera I, Capone R, Cauvi DM, Arispe N, De Maio A. Modulation of Alzheimer's amyloid β peptide oligomerization and toxicity by extracellular Hsp70. Cell Stress Chaperones 2018; 23:269-279. [PMID: 28956268 PMCID: PMC5823807 DOI: 10.1007/s12192-017-0839-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 08/09/2017] [Accepted: 08/10/2017] [Indexed: 01/20/2023] Open
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disorder leading to dementia caused by advanced neuronal dysfunction and death. The most significant symptoms of AD are observed at late stages of the disease when interventions are most likely too late to ameliorate the condition. Currently, the predominant theory for AD is the "amyloid hypothesis," which states that abnormally increased levels of amyloid β (Aβ) peptides result in the production of a variety of aggregates that are neurotoxic. The specific mechanisms for Aβ peptide-induced cytotoxicity have not yet been completely elucidated. However, since the majority of Aβ is released into the extracellular milieu, it is reasonable to assume that toxicity begins outside the cells and makes its way inside where it disrupts the basic cellular process resulting in cell death. There is increasing evidence that hsp, particularly Hsp70, are exported into the extracellular milieu by an active export mechanism independent of cell death. Therefore, both Aβ peptides and Hsp70 may coexist in a common environment during pathological conditions. We observed that Hsp70 affected the Aβ assembling process in vitro preventing oligomer formation. Moreover, the presence of Hsp70 reduced the Aβ peptide-induced toxicity of cultured neurons (N2A cells). These results suggest a potential mechanism for the reduction of the detrimental effects of Aβ peptides in AD.
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Affiliation(s)
- Isabel Rivera
- Division of Trauma, Critical Care, Burns and Acute Care Surgery, Department of Surgery and Department of Neurosciences, School of Medicine, University of California San Diego, 9500 Gilman Drive, #0739, La Jolla, 92093-0739, CA, USA
- Initiative for Maximizing Student Development (IMSD) Program, University of California San Diego, La Jolla, CA, USA
| | - Ricardo Capone
- Division of Trauma, Critical Care, Burns and Acute Care Surgery, Department of Surgery and Department of Neurosciences, School of Medicine, University of California San Diego, 9500 Gilman Drive, #0739, La Jolla, 92093-0739, CA, USA
| | - David M Cauvi
- Division of Trauma, Critical Care, Burns and Acute Care Surgery, Department of Surgery and Department of Neurosciences, School of Medicine, University of California San Diego, 9500 Gilman Drive, #0739, La Jolla, 92093-0739, CA, USA
| | - Nelson Arispe
- Department of Anatomy, Physiology and Genetics, Uniformed Services University School of Medicine, 4301 Jones Bridge Road, Bethesda, MD, 20814, USA
| | - Antonio De Maio
- Division of Trauma, Critical Care, Burns and Acute Care Surgery, Department of Surgery and Department of Neurosciences, School of Medicine, University of California San Diego, 9500 Gilman Drive, #0739, La Jolla, 92093-0739, CA, USA.
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Liu Y, Ren B, Zhang Y, Sun Y, Chang Y, Liang G, Xu L, Zheng J. Molecular simulation aspects of amyloid peptides at membrane interface. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1860:1906-1916. [PMID: 29421626 DOI: 10.1016/j.bbamem.2018.02.004] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 01/31/2018] [Accepted: 02/01/2018] [Indexed: 12/13/2022]
Abstract
The interactions of amyloid peptides with cell membranes play an important role in maintaining the integrity and functionality of cell membrane. A thorough molecular-level understanding of the structure, dynamics, and interactions between amyloid peptides and cell membranes is critical to amyloid aggregation and toxicity mechanisms for the bench-to-bedside applications. Here we review the most recent computational studies of amyloid peptides at model cell membranes. Different mechanisms of action of amyloid peptides on/in cell membranes, targeted by different computational techniques at different lengthscales and timescales, are rationally discussed. Finally, we have proposed some new insights into the remaining challenges and perspectives for future studies to improve our understanding of the activity of amyloid peptides associated with protein-misfolding diseases. This article is part of a Special Issue entitled: Protein Aggregation and Misfolding at the Cell Membrane Interface edited by Ayyalusamy Ramamoorthy.
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Affiliation(s)
- Yonglan Liu
- Hunan Key Laboratory of Biomedical Nanomaterials and Devices, College of Life Science and Chemistry, Hunan University of Technology, Zhuzhou 412007, PR China; Department of Chemical and Biomolecular Engineering, The University of Akron, Akron, OH 44325, United States
| | - Baiping Ren
- Department of Chemical and Biomolecular Engineering, The University of Akron, Akron, OH 44325, United States
| | - Yanxian Zhang
- Department of Chemical and Biomolecular Engineering, The University of Akron, Akron, OH 44325, United States
| | - Yan Sun
- Department of Biochemical Engineering and Key Laboratory of Systems Bioengineering of the Ministry of Education School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
| | - Yung Chang
- R&D Center for Membrane Technology and Department of Chemical EngineeringChung Yuan Christian University, Chung-Li, Taoyuan 320, Taiwan
| | - Guizhao Liang
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044, PR China
| | - Lijian Xu
- Hunan Key Laboratory of Biomedical Nanomaterials and Devices, College of Life Science and Chemistry, Hunan University of Technology, Zhuzhou 412007, PR China; Department of Chemical and Biomolecular Engineering, The University of Akron, Akron, OH 44325, United States.
| | - Jie Zheng
- Department of Chemical and Biomolecular Engineering, The University of Akron, Akron, OH 44325, United States.
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Fernández-Pérez EJ, Sepúlveda FJ, Peters C, Bascuñán D, Riffo-Lepe NO, González-Sanmiguel J, Sánchez SA, Peoples RW, Vicente B, Aguayo LG. Effect of Cholesterol on Membrane Fluidity and Association of Aβ Oligomers and Subsequent Neuronal Damage: A Double-Edged Sword. Front Aging Neurosci 2018. [PMID: 30123122 DOI: 10.3389/fnagi.2018.002.26] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/09/2023] Open
Abstract
Background: The beta-amyloid peptide (Aβ) involved in Alzheimer's disease (AD) has been described to associate/aggregate on the cell surface disrupting the membrane through pore formation and breakage. However, molecular determinants involved for this interaction (e.g., some physicochemical properties of the cell membrane) are largely unknown. Since cholesterol is an important molecule for membrane structure and fluidity, we examined the effect of varying cholesterol content with the association and membrane perforation by Aβ in cultured hippocampal neurons. Methods: To decrease or increase the levels of cholesterol in the membrane we used methyl-β-cyclodextrin (MβCD) and MβCD/cholesterol, respectively. We analyzed if membrane fluidity was affected using generalized polarization (GP) imaging and the fluorescent dye di-4-ANEPPDHQ. Additionally membrane association and perforation was assessed using immunocytochemistry and electrophysiological techniques, respectively. Results: The results showed that cholesterol removal decreased the macroscopic association of Aβ to neuronal membranes (fluorescent-puncta/20 μm: control = 18 ± 2 vs. MβCD = 10 ± 1, p < 0.05) and induced a facilitation of the membrane perforation by Aβ with respect to control cells (half-time for maximal charge transferred: control = 7.2 vs. MβCD = 4.4). Under this condition, we found an increase in membrane fluidity (46 ± 3.3% decrease in GP value, p < 0.001). On the contrary, increasing cholesterol levels incremented membrane rigidity (38 ± 2.7% increase in GP value, p < 0.001) and enhanced the association and clustering of Aβ (fluorescent-puncta/20 μm: control = 18 ± 2 vs. MβCD = 10 ± 1, p < 0.01), but inhibited membrane disruption. Conclusion: Our results strongly support the significance of plasma membrane organization in the toxic effects of Aβ in hippocampal neurons, since fluidity can regulate distribution and insertion of the Aβ peptide in the neuronal membrane.
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Affiliation(s)
- Eduardo J Fernández-Pérez
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
| | - Fernando J Sepúlveda
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
| | - Christian Peters
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
| | - Denisse Bascuñán
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
| | - Nicolás O Riffo-Lepe
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
| | | | - Susana A Sánchez
- Departamento de Polímeros, Facultad de Ciencias Químicas, Universidad de Concepción, Concepción, Chile
| | - Robert W Peoples
- Department of Biomedical Sciences, Marquette University, Milwaukee, WI, United States
| | - Benjamín Vicente
- Department of Psychiatry and Mental Health, Universidad de Concepción, Concepción, Chile
| | - Luis G Aguayo
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
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Chakraborty S, Rakshit J, Bandyopadhyay J, Basu S. Multi-functional neuroprotective activity of neohesperidin dihydrochalcone: a novel scaffold for Alzheimer's disease therapeutics identified via drug repurposing screening. NEW J CHEM 2018. [DOI: 10.1039/c8nj00853a] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Multi-target screening identifies neohesperidin dihydrochalcone for Alzheimer's disease therapeutics, which exhibits strong BACE1 and amyloid aggregation inhibition along with antioxidant activity.
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Affiliation(s)
| | - Jyotirmoy Rakshit
- Department of Biotechnology
- Maulana Abul Kalam Azad University of Technology
- Kolkata 700064
- India
| | - Jaya Bandyopadhyay
- Department of Biotechnology
- Maulana Abul Kalam Azad University of Technology
- Kolkata 700064
- India
| | - Soumalee Basu
- Department of Microbiology
- University of Calcutta
- Kolkata – 700 019
- India
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Sciacca MFM, Monaco I, La Rosa C, Milardi D. The active role of Ca2+ ions in Aβ-mediated membrane damage. Chem Commun (Camb) 2018; 54:3629-3631. [DOI: 10.1039/c8cc01132j] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Calcium ions inhibits Aβ induced membrane poration by small-sized oligomers but significantly foster fiber-dependent membrane disruption.
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Affiliation(s)
- Michele F. M. Sciacca
- Istituto di Biostrutture e Bioimmagini
- Consiglio Nazionale delle Ricerche
- Sede Secondaria di Catania
- Catania
- Italy
| | - Irene Monaco
- Istituto di Biostrutture e Bioimmagini
- Consiglio Nazionale delle Ricerche
- Sede Secondaria di Catania
- Catania
- Italy
| | - Carmelo La Rosa
- Università degli Studi di Catania
- Dipartimento di Scienze Chimiche
- 95125 Catania
- Italy
| | - Danilo Milardi
- Istituto di Biostrutture e Bioimmagini
- Consiglio Nazionale delle Ricerche
- Sede Secondaria di Catania
- Catania
- Italy
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González-Reyes RE, Nava-Mesa MO, Vargas-Sánchez K, Ariza-Salamanca D, Mora-Muñoz L. Involvement of Astrocytes in Alzheimer's Disease from a Neuroinflammatory and Oxidative Stress Perspective. Front Mol Neurosci 2017; 10:427. [PMID: 29311817 PMCID: PMC5742194 DOI: 10.3389/fnmol.2017.00427] [Citation(s) in RCA: 329] [Impact Index Per Article: 47.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 12/06/2017] [Indexed: 12/19/2022] Open
Abstract
Alzheimer disease (AD) is a frequent and devastating neurodegenerative disease in humans, but still no curative treatment has been developed. Although many explicative theories have been proposed, precise pathophysiological mechanisms are unknown. Due to the importance of astrocytes in brain homeostasis they have become interesting targets for the study of AD. Changes in astrocyte function have been observed in brains from individuals with AD, as well as in AD in vitro and in vivo animal models. The presence of amyloid beta (Aβ) has been shown to disrupt gliotransmission, neurotransmitter uptake, and alter calcium signaling in astrocytes. Furthermore, astrocytes express apolipoprotein E and are involved in the production, degradation and removal of Aβ. As well, changes in astrocytes that precede other pathological characteristics observed in AD, point to an early contribution of astroglia in this disease. Astrocytes participate in the inflammatory/immune responses of the central nervous system. The presence of Aβ activates different cell receptors and intracellular signaling pathways, mainly the advanced glycation end products receptor/nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathway, responsible for the transcription of pro-inflammatory cytokines and chemokines in astrocytes. The release of these pro-inflammatory agents may induce cellular damage or even stimulate the production of Aβ in astrocytes. Additionally, Aβ induces the appearance of oxidative stress (OS) and production of reactive oxygen species and reactive nitrogen species in astrocytes, affecting among others, intracellular calcium levels, NADPH oxidase (NOX), NF-κB signaling, glutamate uptake (increasing the risk of excitotoxicity) and mitochondrial function. Excessive neuroinflammation and OS are observed in AD, and astrocytes seem to be involved in both. The Aβ/NF-κB interaction in astrocytes may play a central role in these inflammatory and OS changes present in AD. In this paper, we also discuss therapeutic measures highlighting the importance of astrocytes in AD pathology. Several new therapeutic approaches involving phenols (curcumin), phytoestrogens (genistein), neuroesteroids and other natural phytochemicals have been explored in astrocytes, obtaining some promising results regarding cognitive improvements and attenuation of neuroinflammation. Novel strategies comprising astrocytes and aimed to reduce OS in AD have also been proposed. These include estrogen receptor agonists (pelargonidin), Bambusae concretio Salicea, Monascin, and various antioxidatives such as resveratrol, tocotrienol, anthocyanins, and epicatechin, showing beneficial effects in AD models.
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Affiliation(s)
- Rodrigo E González-Reyes
- Grupo de Investigación en Neurociencias (NeURos), Escuela de Medicina y Ciencias de la Salud, Universidad del Rosario, Bogotá, Colombia
| | - Mauricio O Nava-Mesa
- Grupo de Investigación en Neurociencias (NeURos), Escuela de Medicina y Ciencias de la Salud, Universidad del Rosario, Bogotá, Colombia
| | - Karina Vargas-Sánchez
- Biomedical Sciences Research Group, School of Medicine, Universidad Antonio Nariño, Bogotá, Colombia
| | - Daniel Ariza-Salamanca
- Grupo de Investigación en Neurociencias (NeURos), Escuela de Medicina y Ciencias de la Salud, Universidad del Rosario, Bogotá, Colombia
| | - Laura Mora-Muñoz
- Grupo de Investigación en Neurociencias (NeURos), Escuela de Medicina y Ciencias de la Salud, Universidad del Rosario, Bogotá, Colombia
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Polanco JC, Li C, Bodea LG, Martinez-Marmol R, Meunier FA, Götz J. Amyloid-β and tau complexity — towards improved biomarkers and targeted therapies. Nat Rev Neurol 2017; 14:22-39. [DOI: 10.1038/nrneurol.2017.162] [Citation(s) in RCA: 235] [Impact Index Per Article: 33.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Role of membrane GM1 on early neuronal membrane actions of Aβ during onset of Alzheimer's disease. Biochim Biophys Acta Mol Basis Dis 2017; 1863:3105-3116. [DOI: 10.1016/j.bbadis.2017.08.013] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Revised: 07/19/2017] [Accepted: 08/14/2017] [Indexed: 11/21/2022]
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Sáez-Orellana F, Fuentes-Fuentes MC, Godoy PA, Silva-Grecchi T, Panes JD, Guzmán L, Yévenes GE, Gavilán J, Egan TM, Aguayo LG, Fuentealba J. P2X receptor overexpression induced by soluble oligomers of amyloid beta peptide potentiates synaptic failure and neuronal dyshomeostasis in cellular models of Alzheimer's disease. Neuropharmacology 2017; 128:366-378. [PMID: 29079292 DOI: 10.1016/j.neuropharm.2017.10.027] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2017] [Revised: 10/13/2017] [Accepted: 10/21/2017] [Indexed: 12/17/2022]
Abstract
The most common cause of dementia is Alzheimer's disease. The etiology of the disease is unknown, although considerable evidence suggests a critical role for the soluble oligomers of amyloid beta peptide (Aβ). Because Aβ increases the expression of purinergic receptors (P2XRs) in vitro and in vivo, we studied the functional correlation between long-term exposure to Aβ and the ability of P2XRs to modulate network synaptic tone. We used electrophysiological recordings and Ca2+ microfluorimetry to assess the effects of chronic exposure (24 h) to Aβ oligomers (0.5 μM) together with known inhibitors of P2XRs, such as PPADS and apyrase on synaptic function. Changes in the expression of P2XR were quantified using RT-qPCR. We observed changes in the expression of P2X1R, P2X7R and an increase in P2X2R; and also in protein levels in PC12 cells (143%) and hippocampal neurons (120%) with Aβ. In parallel, the reduction on the frequency and amplitude of mEPSCs (72% and 35%, respectively) were prevented by P2XR inhibition using a low PPADS concentration. Additionally, the current amplitude and intracellular Ca2+ signals evoked by extracellular ATP were increased (70% and 75%, respectively), suggesting an over activation of purinergic neurotransmission in cells pre-treated with Aβ. Taken together, our findings suggest that Aβ disrupts the main components of synaptic transmission at both pre- and post-synaptic sites, and induces changes in the expression of key P2XRs, especially P2X2R; changing the neuromodulator function of the purinergic tone that could involve the P2X2R as a key factor for cytotoxic mechanisms. These results identify novel targets for the treatment of dementia and other diseases characterized by increased purinergic transmission.
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Affiliation(s)
- Francisco Sáez-Orellana
- Neuroactive Compounds Screening Laboratory, Physiology Department, Biological Sciences Faculty, Universidad de Concepción, Concepción, Chile
| | - María C Fuentes-Fuentes
- Neuroactive Compounds Screening Laboratory, Physiology Department, Biological Sciences Faculty, Universidad de Concepción, Concepción, Chile
| | - Pamela A Godoy
- Neuroactive Compounds Screening Laboratory, Physiology Department, Biological Sciences Faculty, Universidad de Concepción, Concepción, Chile
| | - Tiare Silva-Grecchi
- Neuroactive Compounds Screening Laboratory, Physiology Department, Biological Sciences Faculty, Universidad de Concepción, Concepción, Chile
| | - Jessica D Panes
- Neuroactive Compounds Screening Laboratory, Physiology Department, Biological Sciences Faculty, Universidad de Concepción, Concepción, Chile
| | - Leonardo Guzmán
- Molecular Neurobiology Laboratory, Physiology Department, Biological Sciences Faculty, Universidad de Concepción, Concepción, Chile
| | - Gonzalo E Yévenes
- Neuropharmacology Laboratory, Physiology Department, Biological Sciences Faculty, Universidad de Concepción, Concepción, Chile
| | - Javiera Gavilán
- Neuroactive Compounds Screening Laboratory, Physiology Department, Biological Sciences Faculty, Universidad de Concepción, Concepción, Chile
| | - Terrance M Egan
- Department of Pharmacology and Physiology, School of Medicine, Saint Louis University, St. Louis, MO, USA
| | - Luis G Aguayo
- Neuropharmacology Laboratory, Physiology Department, Biological Sciences Faculty, Universidad de Concepción, Concepción, Chile
| | - Jorge Fuentealba
- Neuroactive Compounds Screening Laboratory, Physiology Department, Biological Sciences Faculty, Universidad de Concepción, Concepción, Chile.
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Lockhart C, Klimov DK. Cholesterol Changes the Mechanisms of Aβ Peptide Binding to the DMPC Bilayer. J Chem Inf Model 2017; 57:2554-2565. [PMID: 28910085 DOI: 10.1021/acs.jcim.7b00431] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Using isobaric-isothermal all-atom replica-exchange molecular dynamics (REMD) simulations, we investigated the equilibrium binding of Aβ10-40 monomers to the zwitterionic dimyristoylphosphatidylcholine (DMPC) bilayer containing cholesterol. Our previous REMD simulations, which studied binding of the same peptide to the cholesterol-free DMPC bilayer, served as a control, against which we measured the impact of cholesterol. Our findings are as follows. First, addition of cholesterol to the DMPC bilayer partially expels the Aβ peptide from the hydrophobic core and promotes its binding to bilayer polar headgroups. Using thermodynamic and energetics analyses, we argued that Aβ partial expulsion is not related to cholesterol-induced changes in lateral pressure within the bilayer but is caused by binding energetics, which favors Aβ binding to the surface of the densely packed cholesterol-rich bilayer. Second, cholesterol has a protective effect on the DMPC bilayer structure against perturbations caused by Aβ binding. More specifically, cholesterol reduces bilayer thinning and overall depletion of bilayer density beneath the Aβ binding footprint. Third, we found that the Aβ peptide contains a single cholesterol binding site, which involves hydrophobic C-terminal amino acids (Ile31-Val36), Phe19, and Phe20 from the central hydrophobic cluster, and cationic Lys28 from the turn region. This binding site accounts for about 76% of all Aβ-cholesterol interactions. Because cholesterol binding site in the Aβ10-40 peptide does not contain the GXXXG motif featured in cholesterol interactions with the transmembrane domain C99 of the β-amyloid precursor protein, we argued that the binding mechanisms for Aβ and C99 are distinct reflecting their different conformations and positions in the lipid bilayer. Fourth, cholesterol sharply reduces the helical propensity in the bound Aβ peptide. As a result, cholesterol largely eliminates the emergence of helical structure observed upon Aβ transition from a water environment to the cholesterol-free DMPC bilayer. We explain this effect by the formation of hydrogen bonds between cholesterol and the Aβ backbone, which prevent helix formation. Taken together, we expect that our simulations will advance understanding of a molecular-level mechanism behind the role of cholesterol in Alzheimer's disease.
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Affiliation(s)
- Christopher Lockhart
- School of Systems Biology, George Mason University , Manassas, Virginia 20110, United States
| | - Dmitri K Klimov
- School of Systems Biology, George Mason University , Manassas, Virginia 20110, United States
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50
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Liang J, Kulasiri D, Samarasinghe S. Computational investigation of Amyloid-β-induced location- and subunit-specific disturbances of NMDAR at hippocampal dendritic spine in Alzheimer's disease. PLoS One 2017; 12:e0182743. [PMID: 28837653 PMCID: PMC5570373 DOI: 10.1371/journal.pone.0182743] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2016] [Accepted: 07/24/2017] [Indexed: 01/22/2023] Open
Abstract
In Alzheimer’s disease (AD), dysregulation of intracellular Ca2+ signalling has been observed as an early event prior to the presence of clinical symptoms and is believed to be a crucial factor contributing to AD pathogenesis. Amyloid-β oligomers (AβOs) disturb the N-methyl-D-aspartate receptor (NMDAR)-mediated postsynaptic Ca2+ signalling in response to presynaptic stimulation by increasing the availability of extracellular glutamate as well as directly disturbing the NMDARs. The abnormal Ca2+ response can further lead to impairments in long-term potentiation (LTP), an important process in memory formation. In this study, we develop a mathematical model of a CA1 pyramidal dendritic spine and conduct computational experiments. We use this model to mimic alterations by AβOs under AD conditions to investigate how they are involved in the Ca2+ dysregulation in the dendritic spine. The alterations in glutamate availability, as well as NMDAR availability and activity, are studied both individually and globally. The simulation results suggest that alterations in glutamate availability mostly affect the synaptic response and have limited effects on the extrasynaptic receptors. Moreover, overactivation of extrasynaptic NMDARs in AD is unlikely to be induced by presynaptic stimulation, but by upregulation of the resting level of glutamate, possibly resulting from these alterations. Furthermore, internalisation of synaptic NR2A-NMDAR shows greater damage to the postsynaptic Ca2+ response in comparison with the internalisation of NR2B-NMDARs; thus, the suggested neuroprotective role of the latter is very limited during synaptic transmission in AD. We integrate a CaMKII state transition model with the Ca2+ model to further study the effects of alterations of NMDARs in the CaMKII state transition, an important downstream event in the early phase of LTP. The model reveals that cooperation between NR2A- and NR2B-NMDAR is required for LTP induction. Under AD conditions, internalisation of membrane NMDARs is suggested to be the cause of the loss of synapse numbers by disrupting CaMKII-NMDAR formation.
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Affiliation(s)
- Jingyi Liang
- Centre for Advanced Computational Solutions (C-fACS), Lincoln University, Christchurch, New Zealand
| | - Don Kulasiri
- Centre for Advanced Computational Solutions (C-fACS), Lincoln University, Christchurch, New Zealand
- * E-mail:
| | - Sandhya Samarasinghe
- Centre for Advanced Computational Solutions (C-fACS), Lincoln University, Christchurch, New Zealand
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