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Fourriere L, Gleeson PA. Organelle perturbation in Alzheimer's disease: do intracellular amyloid-ß and the fragmented Golgi mediate early intracellular neurotoxicity? Front Cell Dev Biol 2025; 13:1550211. [PMID: 40302938 PMCID: PMC12037564 DOI: 10.3389/fcell.2025.1550211] [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: 12/23/2024] [Accepted: 03/17/2025] [Indexed: 05/02/2025] Open
Abstract
Alzheimer's disease is a devastating and incurable neurological disease. Most of the current research has focused on developing drugs to clear the extracellular amyloid plaques in the brain of Alzheimer's disease patients. However, this approach is limited as it does not treat the underlying cause of the disease. In this review, we highlight the evidence in the field showing that the accumulation of intracellular toxic amyloid-ß could underpin very early events in neuronal death in both familial early-onset and sporadic late-onset alzheimer's disease. Indeed, intracellular amyloid-ß, which is produced within intracellular compartments, has been shown to perturb endosomal and secretory organelles, in different neuronal models, and the brain of Alzheimer's patients, leading to membrane trafficking defects and perturbation of neuronal function associated with cognition defects. The Golgi apparatus is a central transport and signaling hub at the crossroads of the secretory and endocytic pathways and perturbation of the Golgi ribbon structure is a hallmark of Alzheimer's disease. Here, we discuss the role of the Golgi as a major player in the regulation of amyloid-β production and propose that the Golgi apparatus plays a key role in a cellular network which can seed the onset of Alzheimer's disease. Moreover, we propose that the Golgi is central in an intracellular feedback loop leading to an enhanced level of amyloid-β production resulting in early neuronal defects before the appearance of clinical symptoms. Further advances in defining the molecular pathways of this intracellular feedback loop could support the design of new therapeutic strategies to target a primary source of neuronal toxicity in this disease.
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Rabanal-Ruiz Y, Pedrero-Prieto CM, Sanchez-Rodriguez L, Flores-Cuadrado A, Saiz-Sanchez D, Frontinan-Rubio J, Ubeda-Banon I, Duran Prado M, Martinez-Marcos A, Peinado JR. Differential accumulation of human β-amyloid and tau from enriched extracts in neuronal and endothelial cells. Biochim Biophys Acta Mol Basis Dis 2024; 1870:167204. [PMID: 38679217 DOI: 10.1016/j.bbadis.2024.167204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 04/23/2024] [Accepted: 04/23/2024] [Indexed: 05/01/2024]
Abstract
While Aβ and Tau cellular distribution has been largely studied, the comparative internalization and subcellular accumulation of Tau and Aβ isolated from human brain extracts in endothelial and neuronal cells has not yet been unveiled. We have previously demonstrated that controlled enrichment of Aβ from human brain extracts constitutes a valuable tool to monitor cellular internalization in vitro and in vivo. Herein, we establish an alternative method to strongly enrich Aβ and Tau aggregates from human AD brains, which has allowed us to study and compare the cellular internalization, distribution and toxicity of both proteins within brain barrier endothelial (bEnd.3) and neuronal (Neuro2A) cells. Our findings demonstrate the suitability of human enriched brain extracts to monitor the intracellular distribution of human Aβ and Tau, which, once internalized, show dissimilar sorting to different organelles within the cell and differential toxicity, exhibiting higher toxic effects on neuronal cells than on endothelial cells. While tau is strongly concentrated preferentially in mitochondria, Aβ is distributed predominantly within the endolysosomal system in endothelial cells, whereas the endoplasmic reticulum was its preferential location in neurons. Altogether, our findings display a picture of the interactions that human Aβ and Tau might establish in these cells.
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Affiliation(s)
- Y Rabanal-Ruiz
- Department of Medical Sciences, Ciudad Real Medical School, Oxidative Stress and Neurodegeneration Group, Regional Center for Biomedical Research, University of Castilla-La Mancha, Ciudad Real, Spain
| | - C M Pedrero-Prieto
- Department of Medical Sciences, Ciudad Real Medical School, Oxidative Stress and Neurodegeneration Group, Regional Center for Biomedical Research, University of Castilla-La Mancha, Ciudad Real, Spain
| | - L Sanchez-Rodriguez
- Department of Medical Sciences, Ciudad Real Medical School, Oxidative Stress and Neurodegeneration Group, Regional Center for Biomedical Research, University of Castilla-La Mancha, Ciudad Real, Spain
| | - A Flores-Cuadrado
- Department of Medical Sciences, Ciudad Real Medical School, Neuroplasticity and Neurodegeneration Group, Regional Center for Biomedical Research, University of Castilla-La Mancha, Ciudad Real, Spain
| | - D Saiz-Sanchez
- Department of Medical Sciences, Ciudad Real Medical School, Neuroplasticity and Neurodegeneration Group, Regional Center for Biomedical Research, University of Castilla-La Mancha, Ciudad Real, Spain
| | - J Frontinan-Rubio
- Department of Medical Sciences, Ciudad Real Medical School, Oxidative Stress and Neurodegeneration Group, Regional Center for Biomedical Research, University of Castilla-La Mancha, Ciudad Real, Spain
| | - I Ubeda-Banon
- Department of Medical Sciences, Ciudad Real Medical School, Neuroplasticity and Neurodegeneration Group, Regional Center for Biomedical Research, University of Castilla-La Mancha, Ciudad Real, Spain
| | - M Duran Prado
- Department of Medical Sciences, Ciudad Real Medical School, Oxidative Stress and Neurodegeneration Group, Regional Center for Biomedical Research, University of Castilla-La Mancha, Ciudad Real, Spain
| | - A Martinez-Marcos
- Department of Medical Sciences, Ciudad Real Medical School, Neuroplasticity and Neurodegeneration Group, Regional Center for Biomedical Research, University of Castilla-La Mancha, Ciudad Real, Spain.
| | - Juan R Peinado
- Department of Medical Sciences, Ciudad Real Medical School, Oxidative Stress and Neurodegeneration Group, Regional Center for Biomedical Research, University of Castilla-La Mancha, Ciudad Real, Spain.
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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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Kuhn TB, Minamide LS, Tahtamouni LH, Alderfer SA, Walsh KP, Shaw AE, Yanouri O, Haigler HJ, Ruff MR, Bamburg JR. Chemokine Receptor Antagonists Prevent and Reverse Cofilin-Actin Rod Pathology and Protect Synapses in Cultured Rodent and Human iPSC-Derived Neurons. Biomedicines 2024; 12:93. [PMID: 38255199 PMCID: PMC10813319 DOI: 10.3390/biomedicines12010093] [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: 11/17/2023] [Revised: 12/20/2023] [Accepted: 12/26/2023] [Indexed: 01/24/2024] Open
Abstract
Synapse loss is the principal cause of cognitive decline in Alzheimer's disease (AD) and related disorders (ADRD). Synapse development depends on the intricate dynamics of the neuronal cytoskeleton. Cofilin, the major protein regulating actin dynamics, can be sequestered into cofilactin rods, intra-neurite bundles of cofilin-saturated actin filaments that can disrupt vesicular trafficking and cause synaptic loss. Rods are a brain pathology in human AD and mouse models of AD and ADRD. Eliminating rods is the focus of this paper. One pathway for rod formation is triggered in ~20% of rodent hippocampal neurons by disease-related factors (e.g., soluble oligomers of Amyloid-β (Aβ)) and requires cellular prion protein (PrPC), active NADPH oxidase (NOX), and cytokine/chemokine receptors (CCRs). FDA-approved antagonists of CXCR4 and CCR5 inhibit Aβ-induced rods in both rodent and human neurons with effective concentrations for 50% rod reduction (EC50) of 1-10 nM. Remarkably, two D-amino acid receptor-active peptides (RAP-103 and RAP-310) inhibit Aβ-induced rods with an EC50 of ~1 pM in mouse neurons and ~0.1 pM in human neurons. These peptides are analogs of D-Ala-Peptide T-Amide (DAPTA) and share a pentapeptide sequence (TTNYT) antagonistic to several CCR-dependent responses. RAP-103 does not inhibit neuritogenesis or outgrowth even at 1 µM, >106-fold above its EC50. N-terminal methylation, or D-Thr to D-Ser substitution, decreases the rod-inhibiting potency of RAP-103 by 103-fold, suggesting high target specificity. Neither RAP peptide inhibits neuronal rod formation induced by excitotoxic glutamate, but both inhibit rods induced in human neurons by several PrPC/NOX pathway activators (Aβ, HIV-gp120 protein, and IL-6). Significantly, RAP-103 completely protects against Aβ-induced loss of mature and developing synapses and, at 0.1 nM, reverses rods in both rodent and human neurons (T½ ~ 3 h) even in the continuous presence of Aβ. Thus, this orally available, brain-permeable peptide should be highly effective in reducing rod pathology in multifactorial neurological diseases with mixed proteinopathies acting through PrPC/NOX.
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Affiliation(s)
- Thomas B. Kuhn
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523, USA; (T.B.K.); (L.S.M.); (L.H.T.); (K.P.W.); (A.E.S.)
| | - Laurie S. Minamide
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523, USA; (T.B.K.); (L.S.M.); (L.H.T.); (K.P.W.); (A.E.S.)
| | - Lubna H. Tahtamouni
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523, USA; (T.B.K.); (L.S.M.); (L.H.T.); (K.P.W.); (A.E.S.)
- Department of Biology and Biotechnology, Faculty of Science, The Hashemite University, Zarqa 13133, Jordan
| | - Sydney A. Alderfer
- Department of Chemical and Biological Engineering and School of Biomedical Engineering, Colorado State University, Fort Collins, CO 80523, USA;
| | - Keifer P. Walsh
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523, USA; (T.B.K.); (L.S.M.); (L.H.T.); (K.P.W.); (A.E.S.)
| | - Alisa E. Shaw
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523, USA; (T.B.K.); (L.S.M.); (L.H.T.); (K.P.W.); (A.E.S.)
| | - Omar Yanouri
- Molecular, Cellular and Integrative Neuroscience Program, Colorado State University, Fort Collins, CO 80523, USA;
| | - Henry J. Haigler
- Creative Bio-Peptides, Inc., 10319 Glen Road, Suite 100, Potomac, MD 20854, USA; (H.J.H.); (M.R.R.)
| | - Michael R. Ruff
- Creative Bio-Peptides, Inc., 10319 Glen Road, Suite 100, Potomac, MD 20854, USA; (H.J.H.); (M.R.R.)
| | - James R. Bamburg
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523, USA; (T.B.K.); (L.S.M.); (L.H.T.); (K.P.W.); (A.E.S.)
- Molecular, Cellular and Integrative Neuroscience Program, Colorado State University, Fort Collins, CO 80523, USA;
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Salazar J, Samhan-Arias AK, Gutierrez-Merino C. The Use of Flavylium Salts as Dynamic Inhibitor Moieties for Human C b5R. Molecules 2022; 28:123. [PMID: 36615312 PMCID: PMC10609148 DOI: 10.3390/molecules28207138] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 12/14/2022] [Accepted: 12/21/2022] [Indexed: 10/29/2023] Open
Abstract
Cytochrome b5 reductase (Cb5R) is a flavoprotein that participates in the reduction of multiple biological redox partners. Co-localization of this protein with nitric oxide sources has been observed in neurons. In addition, the generation of superoxide anion radical by Cb5R has been observed. A search for specific inhibitors of Cb5R to understand the role of this protein in these new functions has been initiated. Previous studies have shown the ability of different flavonoids to inhibit Cb5R. Anthocyanins are a subgroup of flavonoids responsible for most red and blue colors found in flowers and fruits. Although usually represented by the flavylium cation form, these species are only stable at rather acidic pH values (pH ≤ 1). At higher pH values, the flavylium cation is involved in a dynamic reaction network comprising different neutral species with the potential ability to inhibit the activities of Cb5R. This study aims to provide insights into the molecular mechanism of interaction between flavonoids and Cb5R using flavylium salts as dynamic inhibitors. The outcome of this study might lead to the design of improved specific enzyme inhibitors in the future.
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Affiliation(s)
- Jairo Salazar
- Departamento de Química, Universidad Nacional Autónoma de Nicaragua-León, León 21000, Nicaragua
| | - Alejandro K. Samhan-Arias
- Departamento de Bioquímica, Universidad Autónoma de Madrid (UAM), C\Arzobispo Morcillo 4, 28029 Madrid, Spain;
- Instituto de Investigaciones Biomédicas ‘Alberto Sols’ (CSIC-UAM), C\Arturo Duperier 4, 28029 Madrid, Spain
| | - Carlos Gutierrez-Merino
- Instituto de Biomarcadores de Patologías Moleculares, Universidad de Extremadura, 06006 Badajoz, Spain
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Varshavskaya KB, Mitkevich VA, Makarov AA, Barykin EP. Synthetic, Cell-Derived, Brain-Derived, and Recombinant β-Amyloid: Modelling Alzheimer's Disease for Research and Drug Development. Int J Mol Sci 2022; 23:15036. [PMID: 36499362 PMCID: PMC9738609 DOI: 10.3390/ijms232315036] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 11/26/2022] [Accepted: 11/29/2022] [Indexed: 12/02/2022] Open
Abstract
Alzheimer's disease (AD) is the most common cause of dementia in the elderly, characterised by the accumulation of senile plaques and tau tangles, neurodegeneration, and neuroinflammation in the brain. The development of AD is a pathological cascade starting according to the amyloid hypothesis with the accumulation and aggregation of the β-amyloid peptide (Aβ), which induces hyperphosphorylation of tau and promotes the pro-inflammatory activation of microglia leading to synaptic loss and, ultimately, neuronal death. Modelling AD-related processes is important for both studying the molecular basis of the disease and the development of novel therapeutics. The replication of these processes is often achieved with the use of a purified Aβ peptide. However, Aβ preparations obtained from different sources can have strikingly different properties. This review aims to compare the structure and biological effects of Aβ oligomers and aggregates of a higher order: synthetic, recombinant, purified from cell culture, or extracted from brain tissue. The authors summarise the applicability of Aβ preparations for modelling Aβ aggregation, neurotoxicity, cytoskeleton damage, receptor toxicity in vitro and cerebral amyloidosis, synaptic plasticity disruption, and cognitive impairment in vivo and ex vivo. Further, the paper discusses the causes of the reported differences in the effect of Aβ obtained from the sources mentioned above. This review points to the importance of the source of Aβ for AD modelling and could help researchers to choose the optimal way to model the Aβ-induced abnormalities.
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Affiliation(s)
| | | | - Alexander A. Makarov
- Engelhardt Institute of Molecular Biology, Vavilov St. 32, 119991 Moscow, Russia
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Aβ and Tau Interact with Metal Ions, Lipid Membranes and Peptide-Based Amyloid Inhibitors: Are These Common Features Relevant in Alzheimer’s Disease? Molecules 2022; 27:molecules27165066. [PMID: 36014310 PMCID: PMC9414153 DOI: 10.3390/molecules27165066] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 08/04/2022] [Accepted: 08/05/2022] [Indexed: 12/13/2022] Open
Abstract
In the last two decades, the amyloid hypothesis, i.e., the abnormal accumulation of toxic Aβ assemblies in the brain, has been considered the mainstream concept sustaining research in Alzheimer’s Disease (AD). However, the course of cognitive decline and AD development better correlates with tau accumulation rather than amyloid peptide deposition. Moreover, all clinical trials of amyloid-targeting drug candidates have been unsuccessful, implicitly suggesting that the amyloid hypothesis needs significant amendments. Accumulating evidence supports the existence of a series of potentially dangerous relationships between Aβ oligomeric species and tau protein in AD. However, the molecular determinants underlying pathogenic Aβ/tau cross interactions are not fully understood. Here, we discuss the common features of Aβ and tau molecules, with special emphasis on: (i) the critical role played by metal dyshomeostasis in promoting both Aβ and tau aggregation and oxidative stress, in AD; (ii) the effects of lipid membranes on Aβ and tau (co)-aggregation at the membrane interface; (iii) the potential of small peptide-based inhibitors of Aβ and tau misfolding as therapeutic tools in AD. Although the molecular mechanism underlying the direct Aβ/tau interaction remains largely unknown, the arguments discussed in this review may help reinforcing the current view of a synergistic Aβ/tau molecular crosstalk in AD and stimulate further research to mechanism elucidation and next-generation AD therapeutics.
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Kawarabayashi T, Nakamura T, Sato K, Seino Y, Ichii S, Nakahata N, Takatama M, Westaway D, George-Hyslop PS, Shoji M. Lipid Rafts Act as a Common Platform for Amyloid-β Oligomer-Induced Alzheimer’s Disease Pathology. J Alzheimers Dis 2022; 87:1189-1203. [DOI: 10.3233/jad-215662] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Background: Amyloid-β (Aβ) oligomers induce the overproduction of phosphorylated tau and neurodegeneration. These cascades gradually cause cognitive impairment in Alzheimer’s disease (AD). While each pathological event in AD has been studied in detail separately, the spatial and temporal relationships between pathological events in AD remain unclear. Objective: We demonstrated that lipid rafts function as a common platform for the pathological cascades of AD. Methods: Cellular and synaptosomal lipid rafts were prepared from the brains of Aβ amyloid model mice (Tg2576 mice) and double transgenic mice (Tg2576 x TgTauP301L mice) and longitudinally analyzed. Results: Aβ dimers, the cellular prion protein (PrPc), and Aβ dimer/PrPc complexes were detected in the lipid rafts. The levels of Fyn, the phosphorylated NR2B subunit of the N-methyl-D-aspartate receptor, glycogen synthase kinase 3β, total tau, phosphorylated tau, and tau oligomers increased with Aβ dimer accumulation in both the cellular and synaptosomal lipid rafts. Increases in the levels of these molecules were first seen at 6 months of age and corresponded with the early stages of Aβ accumulation in the amyloid model mice. Conclusion: Lipid rafts act as a common platform for the progression of AD pathology. The findings of this study suggest a novel therapeutic approach to AD, involving the modification of lipid raft components and the inhibition of their roles in the sequential pathological events of AD.
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Affiliation(s)
- Takeshi Kawarabayashi
- Department of Neurology, Geriatrics Research Institute and Hospital, Maebashi, Gunma, Japan
- Department of Social Medicine, Hirosaki University Graduate School of Medicine, Hirosaki, Aomori, Japan
- Department of Neurology, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan
| | - Takumi Nakamura
- Department of Social Medicine, Hirosaki University Graduate School of Medicine, Hirosaki, Aomori, Japan
- Department of Neurology, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan
| | - Kaoru Sato
- Department of Orthopaedic Surgery, Hirosaki University Graduate School of Medicine, Hirosaki, Aomori, Japan
| | - Yusuke Seino
- Department of Neurology, Hirosaki National Hospital, Hirosaki, Aomori, Japan
| | - Sadanobu Ichii
- Department of Social Medicine, Hirosaki University Graduate School of Medicine, Hirosaki, Aomori, Japan
| | - Naoko Nakahata
- Department of Social Medicine, Hirosaki University Graduate School of Medicine, Hirosaki, Aomori, Japan
- Department of Speech and Hearing, Hirosaki University of Health and Welfare/JuniorCollege, Hirosaki, Aomori, Japan
| | - Masamitsu Takatama
- Department of Neurology, Geriatrics Research Institute and Hospital, Maebashi, Gunma, Japan
| | - David Westaway
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, AB, Canada
| | - Peter St. George-Hyslop
- Tanz Centre for Research in Neurodegenerative Diseases and Departments of Medicine, Medical Biophysics, and Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| | - Mikio Shoji
- Department of Neurology, Geriatrics Research Institute and Hospital, Maebashi, Gunma, Japan
- Department of Social Medicine, Hirosaki University Graduate School of Medicine, Hirosaki, Aomori, Japan
- Department of Neurology, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan
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Rajendran R, Ragavan RP, Al-Sehemi AG, Uddin MS, Aleya L, Mathew B. Current understandings and perspectives of petroleum hydrocarbons in Alzheimer's disease and Parkinson's disease: a global concern. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:10928-10949. [PMID: 35000177 DOI: 10.1007/s11356-021-17931-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Accepted: 11/30/2021] [Indexed: 06/14/2023]
Abstract
Over the last few decades, the global prevalence of neurodevelopmental and neurodegenerative illnesses has risen rapidly. Although the aetiology remains unclear, evidence is mounting that exposure to persistent hydrocarbon pollutants is a substantial risk factor, predisposing a person to neurological diseases later in life. Epidemiological studies correlate environmental hydrocarbon exposure to brain disorders including neuropathies, cognitive, motor and sensory impairments; neurodevelopmental disorders like autism spectrum disorder (ASD); and neurodegenerative disorders like Alzheimer's disease (AD) and Parkinson's disease (PD). Particulate matter, benzene, toluene, ethylbenzene, xylenes, polycyclic aromatic hydrocarbons and endocrine-disrupting chemicals have all been linked to neurodevelopmental problems in all class of people. There is mounting evidence that supports the prevalence of petroleum hydrocarbon becoming neurotoxic and being involved in the pathogenesis of AD and PD. More study is needed to fully comprehend the scope of these problems in the context of unconventional oil and natural gas. This review summarises in vitro, animal and epidemiological research on the genesis of neurodegenerative disorders, highlighting evidence that supports inexorable role of hazardous hydrocarbon exposure in the pathophysiology of AD and PD. In this review, we offer a summary of the existing evidence gathered through a Medline literature search of systematic reviews and meta-analyses of the most important epidemiological studies published so far.
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Affiliation(s)
- Rajalakshmi Rajendran
- Department of Pharmacy Practice, Amrita School of Pharmacy, Amrita Vishwa Vidyapeetham, Kochi, 682041, Kerala, India
| | - Roshni Pushpa Ragavan
- Research Center for Advanced Materials Science, King Khalid University, Abha, 61413, Saudi Arabia.
| | - Abdullah G Al-Sehemi
- Research Center for Advanced Materials Science, King Khalid University, Abha, 61413, Saudi Arabia
- Department of Chemistry, King Khalid University, Abha, 61413, Saudi Arabia
| | - Md Sahab Uddin
- Department of Pharmacy, Southeast University, Dhaka, Bangladesh
- Pharmakon Neuroscience Research Network, Dhaka, Bangladesh
| | - Lotfi Aleya
- Laboratoire Chrono-Environment, CNRS6249, Universite de Bourgogne Franche-Comte, Besancon, France
| | - Bijo Mathew
- Department of Pharmaceutical Chemistry, Amrita School of Pharmacy, Amrita Vishwa Vidyapeetham, AIMS Health Sciences Campus, Kochi, 682 041, India.
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Yuen SC, Liang X, Zhu H, Jia Y, Leung SW. Prediction of differentially expressed microRNAs in blood as potential biomarkers for Alzheimer's disease by meta-analysis and adaptive boosting ensemble learning. Alzheimers Res Ther 2021; 13:126. [PMID: 34243793 PMCID: PMC8272278 DOI: 10.1186/s13195-021-00862-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Accepted: 06/17/2021] [Indexed: 12/14/2022]
Abstract
BACKGROUND Blood circulating microRNAs that are specific for Alzheimer's disease (AD) can be identified from differentially expressed microRNAs (DEmiRNAs). However, non-reproducible and inconsistent reports of DEmiRNAs hinder biomarker development. The most reliable DEmiRNAs can be identified by meta-analysis. To enrich the pool of DEmiRNAs for potential AD biomarkers, we used a machine learning method called adaptive boosting for miRNA disease association (ABMDA) to identify eligible candidates that share similar characteristics with the DEmiRNAs identified from meta-analysis. This study aimed to identify blood circulating DEmiRNAs as potential AD biomarkers by augmenting meta-analysis with the ABMDA ensemble learning method. METHODS Studies on DEmiRNAs and their dysregulation states were corroborated with one another by meta-analysis based on a random-effects model. DEmiRNAs identified by meta-analysis were collected as positive examples of miRNA-AD pairs for ABMDA ensemble learning. ABMDA identified similar DEmiRNAs according to a set of predefined criteria. The biological significance of all resulting DEmiRNAs was determined by their target genes according to pathway enrichment analyses. The target genes common to both meta-analysis- and ABMDA-identified DEmiRNAs were collected to construct a network to investigate their biological functions. RESULTS A systematic database search found 7841 studies for an extensive meta-analysis, covering 54 independent comparisons of 47 differential miRNA expression studies, and identified 18 reliable DEmiRNAs. ABMDA ensemble learning was conducted based on the meta-analysis results and the Human MicroRNA Disease Database, which identified 10 additional AD-related DEmiRNAs. These 28 DEmiRNAs and their dysregulated pathways were related to neuroinflammation. The dysregulated pathway related to neuronal cell cycle re-entry (CCR) was the only statistically significant pathway of the ABMDA-identified DEmiRNAs. In the biological network constructed from 1865 common target genes of the identified DEmiRNAs, the multiple core ubiquitin-proteasome system, that is involved in neuroinflammation and CCR, was highly connected. CONCLUSION This study identified 28 DEmiRNAs as potential AD biomarkers in blood, by meta-analysis and ABMDA ensemble learning in tandem. The DEmiRNAs identified by meta-analysis and ABMDA were significantly related to neuroinflammation, and the ABMDA-identified DEmiRNAs were related to neuronal CCR.
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Affiliation(s)
- Sze Chung Yuen
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Avenida da Universidade, Taipa, 999078 Macao China
| | - Xiaonan Liang
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Avenida da Universidade, Taipa, 999078 Macao China
| | - Hongmei Zhu
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Avenida da Universidade, Taipa, 999078 Macao China
| | - Yongliang Jia
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Avenida da Universidade, Taipa, 999078 Macao China
- BGI College & Henan Institute of Medical and Pharmaceutical Sciences, Zhengzhou University, Zhengzhou, Henan China
- Department of Obstetrics and Gynecology, The Second Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan China
| | - Siu-wai Leung
- Shenzhen Institute of Artificial Intelligence and Robotics for Society, Shenzhen, China
- Edinburgh Bayes Centre for AI Research in Shenzhen, College of Science and Engineering, University of Edinburgh, Edinburgh, Scotland, UK
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11
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Uddin MS, Al Mamun A, Rahman MA, Behl T, Perveen A, Hafeez A, Bin-Jumah MN, Abdel-Daim MM, Ashraf GM. Emerging Proof of Protein Misfolding and Interactions in Multifactorial Alzheimer's Disease. Curr Top Med Chem 2021; 20:2380-2390. [PMID: 32479244 DOI: 10.2174/1568026620666200601161703] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 04/21/2020] [Accepted: 04/27/2020] [Indexed: 12/23/2022]
Abstract
OBJECTIVE Alzheimer's disease (AD) is a devastating neurodegenerative disorder, characterized by the extracellular accumulations of amyloid beta (Aβ) as senile plaques and intracellular aggregations of tau in the form of neurofibrillary tangles (NFTs) in specific brain regions. In this review, we focus on the interaction of Aβ and tau with cytosolic proteins and several cell organelles as well as associated neurotoxicity in AD. SUMMARY Misfolded proteins present in cells accompanied by correctly folded, intermediately folded, as well as unfolded species. Misfolded proteins can be degraded or refolded properly with the aid of chaperone proteins, which are playing a pivotal role in protein folding, trafficking as well as intermediate stabilization in healthy cells. The continuous aggregation of misfolded proteins in the absence of their proper clearance could result in amyloid disease including AD. The neuropathological changes of AD brain include the atypical cellular accumulation of misfolded proteins as well as the loss of neurons and synapses in the cerebral cortex and certain subcortical regions. The mechanism of neurodegeneration in AD that leads to severe neuronal cell death and memory dysfunctions is not completely understood until now. CONCLUSION Examining the impact, as well as the consequences of protein misfolding, could help to uncover the molecular etiologies behind the complicated AD pathogenesis.
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Affiliation(s)
- Md Sahab Uddin
- Department of Pharmacy, Southeast University, Dhaka, Bangladesh,Pharmakon Neuroscience Research Network, Dhaka, Bangladesh
| | - Abdullah Al Mamun
- Department of Pharmacy, Southeast University, Dhaka, Bangladesh,Pharmakon Neuroscience Research Network, Dhaka, Bangladesh
| | - Md Ataur Rahman
- Center for Neuroscience, Brain Science Institute, Korea Institute of Science and Technology, Seoul, Republic of Korea
| | - Tapan Behl
- Chitkara College of Pharmacy, Chitkara University, Punjab, India
| | - Asma Perveen
- Glocal School of Life Sciences, Glocal University, Saharanpur, India
| | - Abdul Hafeez
- Glocal School of Pharmacy, Glocal University, Saharanpur, India
| | - May N Bin-Jumah
- Department of Biology, College of Science, Princess Nourah bint Abdulrahman University, Riyadh 11474, Saudi Arabia
| | - Mohamed M Abdel-Daim
- Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia,Pharmacology Department, Faculty of Veterinary Medicine, Suez Canal University, Ismailia 41522, Egypt
| | - Ghulam Md Ashraf
- King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia,Department of Medical Laboratory Technology, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
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12
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The Relevance of Amyloid β-Calmodulin Complexation in Neurons and Brain Degeneration in Alzheimer's Disease. Int J Mol Sci 2021; 22:ijms22094976. [PMID: 34067061 PMCID: PMC8125740 DOI: 10.3390/ijms22094976] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 05/02/2021] [Accepted: 05/05/2021] [Indexed: 12/13/2022] Open
Abstract
Intraneuronal amyloid β (Aβ) oligomer accumulation precedes the appearance of amyloid plaques or neurofibrillary tangles and is neurotoxic. In Alzheimer’s disease (AD)-affected brains, intraneuronal Aβ oligomers can derive from Aβ peptide production within the neuron and, also, from vicinal neurons or reactive glial cells. Calcium homeostasis dysregulation and neuronal excitability alterations are widely accepted to play a key role in Aβ neurotoxicity in AD. However, the identification of primary Aβ-target proteins, in which functional impairment initiating cytosolic calcium homeostasis dysregulation and the critical point of no return are still pending issues. The micromolar concentration of calmodulin (CaM) in neurons and its high affinity for neurotoxic Aβ peptides (dissociation constant ≈ 1 nM) highlight a novel function of CaM, i.e., the buffering of free Aβ concentrations in the low nanomolar range. In turn, the concentration of Aβ-CaM complexes within neurons will increase as a function of time after the induction of Aβ production, and free Aβ will rise sharply when accumulated Aβ exceeds all available CaM. Thus, Aβ-CaM complexation could also play a major role in neuronal calcium signaling mediated by calmodulin-binding proteins by Aβ; a point that has been overlooked until now. In this review, we address the implications of Aβ-CaM complexation in the formation of neurotoxic Aβ oligomers, in the alteration of intracellular calcium homeostasis induced by Aβ, and of dysregulation of the calcium-dependent neuronal activity and excitability induced by Aβ.
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13
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Kim CM, Montal V, Diez I, Orwig W, Sepulcre J. Network interdigitations of Tau and amyloid-beta deposits define cognitive levels in aging. Hum Brain Mapp 2021; 42:2990-3004. [PMID: 33955621 PMCID: PMC8193537 DOI: 10.1002/hbm.25350] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 12/16/2020] [Accepted: 01/11/2021] [Indexed: 12/18/2022] Open
Abstract
Amyloid‐beta (Aβ) plaques and tau neurofibrillary tangles are pathological hallmarks of Alzheimer's disease (AD); their contribution to neurodegeneration and clinical manifestations are critical in understanding preclinical AD. At present, the mechanisms related to Aβ and tau pathogenesis leading to cognitive decline in older adults remain largely unknown. Here, we examined graph theory‐based positron emission tomography (PET) analytical approaches, within and between tau and Aβ PET modalities, and tested the effects on cognitive changes in cognitively normal older adults (CN). Particularly, we focused on the network interdigitations of Aβ and tau deposits, along with cognitive test scores in CN at both baseline and 2‐year follow‐up (FU). We found highly significant Aβ‐tau network integrations in AD vulnerable areas, as well as significant associations between those Aβ‐tau interdigitations and general cognitive impairment in CN at baseline and FU. Our findings suggest a distinctive contribution of interlinking network relationships between Aβ and tau deposits in heteromodal areas of the human brain. They support a network‐based interaction between Aβ and tau accumulations as a key factor for cognitive deterioration in CN prior to dementia.
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Affiliation(s)
- Chan-Mi Kim
- Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA.,Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
| | - Victor Montal
- Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA.,Memory Unit, Department of Neurology, Hospital de la Santa Creu i Sant Pau, Biomedical Research Institute Sant Pau, Universitat Autonoma de Barcelona, Barcelona, Spain.,Centro de Investigacón Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Spain
| | - Ibai Diez
- Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA.,Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
| | - William Orwig
- Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA.,Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
| | | | - Jorge Sepulcre
- Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA.,Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
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14
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Saminathan H, Ghosh A, Zhang D, Song C, Jin H, Anantharam V, Kanthasamy A, Kanthasamy AG. Fyn Kinase-Mediated PKCδ Y311 Phosphorylation Induces Dopaminergic Degeneration in Cell Culture and Animal Models: Implications for the Identification of a New Pharmacological Target for Parkinson's Disease. Front Pharmacol 2021; 12:631375. [PMID: 33995031 PMCID: PMC8113680 DOI: 10.3389/fphar.2021.631375] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 04/09/2021] [Indexed: 12/25/2022] Open
Abstract
Oxidative stress, neuroinflammation and apoptosis are some of the key etiological factors responsible for dopamin(DA)ergic degeneration during Parkinson's disease (PD), yet the downstream molecular mechanisms underlying neurodegeneration are largely unknown. Recently, a genome-wide association study revealed the FYN gene to be associated with PD, suggesting that Fyn kinase could be a pharmacological target for PD. In this study, we report that Fyn-mediated PKCδ tyrosine (Y311) phosphorylation is a key event preceding its proteolytic activation in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) model of Parkinsonism. MPP+/MPTP induced Fyn kinase activation in N27 DAergic neuronal cells and the mouse substantia nigra. PKCδ-Y311 phosphorylation by activated Fyn initiates the apoptotic caspase-signaling cascade during DAergic degeneration. Pharmacological attenuation of Fyn activity protected DAergic neurons from MPP+-induced degeneration in primary mesencephalic neuronal cultures. We further employed Fyn wild-type and Fyn knockout (KO) mice to confirm whether Fyn is a valid pharmacological target of DAergic neurodegeneration. Primary mesencephalic neurons from Fyn KO mice were greatly protected from MPP+-induced DAergic cell death, neurite loss and DA reuptake loss. Furthermore, Fyn KO mice were significantly protected from MPTP-induced PKCδ-Y311 phosphorylation, behavioral deficits and nigral DAergic degeneration. This study thus unveils a mechanism by which Fyn regulates PKCδ's pro-apoptotic function and DAergic degeneration. Pharmacological inhibitors directed at Fyn activation could prove to be a novel therapeutic target in the delay or halting of selective DAergic degeneration during PD.
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Affiliation(s)
| | | | | | | | | | | | - Arthi Kanthasamy
- Parkinson Disorders Research Program, Iowa Center for Advanced Neurotoxicology, Department of Biomedical Sciences, Iowa State University, Ames, IA, United States
| | - Anumantha G. Kanthasamy
- Parkinson Disorders Research Program, Iowa Center for Advanced Neurotoxicology, Department of Biomedical Sciences, Iowa State University, Ames, IA, United States
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15
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Poejo J, Salazar J, Mata AM, Gutierrez-Merino C. Binding of Amyloid β(1-42)-Calmodulin Complexes to Plasma Membrane Lipid Rafts in Cerebellar Granule Neurons Alters Resting Cytosolic Calcium Homeostasis. Int J Mol Sci 2021; 22:1984. [PMID: 33671444 PMCID: PMC7923178 DOI: 10.3390/ijms22041984] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Revised: 02/06/2021] [Accepted: 02/09/2021] [Indexed: 12/15/2022] Open
Abstract
Lipid rafts are a primary target in studies of amyloid β (Aβ) cytotoxicity in neurons. Exogenous Aβ peptides bind to lipid rafts, which in turn play a key role in Aβ uptake, leading to the formation of neurotoxic intracellular Aβ aggregates. On the other hand, dysregulation of intracellular calcium homeostasis in neurons has been observed in Alzheimer's disease (AD). In a previous work, we showed that Aβ(1-42), the prevalent Aβ peptide found in the amyloid plaques of AD patients, binds with high affinity to purified calmodulin (CaM), with a dissociation constant ≈1 nM. In this work, to experimentally assess the Aβ(1-42) binding capacity to intracellular CaM, we used primary cultures of mature cerebellar granule neurons (CGN) as a neuronal model. Our results showed a large complexation of submicromolar concentrations of Aβ(1-42) dimers by CaM in CGN, up to 120 ± 13 picomoles of Aβ(1-42) /2.5 × 106 cells. Using fluorescence microscopy imaging, we showed an extensive co-localization of CaM and Aβ(1-42) in lipid rafts in CGN stained with up to 100 picomoles of Aβ(1-42)-HiLyteTM-Fluor555 monomers. Intracellular Aβ(1-42) concentration in this range was achieved by 2 h incubation of CGN with 2 μM Aβ(1-42), and this treatment lowered the resting cytosolic calcium of mature CGN in partially depolarizing 25 mM potassium medium. We conclude that the primary cause of the resting cytosolic calcium decrease is the inhibition of L-type calcium channels of CGN by Aβ(1-42) dimers, whose activity is inhibited by CaM:Aβ(1-42) complexes bound to lipid rafts.
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Affiliation(s)
- Joana Poejo
- Instituto de Biomarcadores de Patologías Moleculares, Universidad de Extremadura, 06006 Badajoz, Spain; (J.P.); (J.S.); (A.M.M.)
| | - Jairo Salazar
- Instituto de Biomarcadores de Patologías Moleculares, Universidad de Extremadura, 06006 Badajoz, Spain; (J.P.); (J.S.); (A.M.M.)
- Departamento de Química, Universidad Nacional Autónoma de Nicaragua-León, León 21000, Nicaragua
| | - Ana M. Mata
- Instituto de Biomarcadores de Patologías Moleculares, Universidad de Extremadura, 06006 Badajoz, Spain; (J.P.); (J.S.); (A.M.M.)
- Departamento de Bioquímica y Biología Molecular y Genética, Facultad de Ciencias, Universidad de Extremadura, 06006 Badajoz, Spain
| | - Carlos Gutierrez-Merino
- Instituto de Biomarcadores de Patologías Moleculares, Universidad de Extremadura, 06006 Badajoz, Spain; (J.P.); (J.S.); (A.M.M.)
- Departamento de Bioquímica y Biología Molecular y Genética, Facultad de Ciencias, Universidad de Extremadura, 06006 Badajoz, Spain
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16
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Engin AB, Engin A. Alzheimer's Disease and Protein Kinases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1275:285-321. [PMID: 33539020 DOI: 10.1007/978-3-030-49844-3_11] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Alzheimer's disease (AD) is the most common neurodegenerative disorder and accounts for more than 60-80% of all cases of dementia. Loss of pyramidal neurons, extracellular amyloid beta (Abeta) accumulated senile plaques, and neurofibrillary tangles that contain hyperphosphorylated tau constitute the main pathological alterations in AD.Synaptic dysfunction and extrasynaptic N-methyl-D-aspartate receptor (NMDAR) hyperactivation contributes to excitotoxicity in patients with AD. Amyloid precursor protein (APP) and Abeta promoted neurodegeneration develop through the activation of protein kinase signaling cascade in AD. Furthermore, ultimate neuronal death in AD is under control of protein kinases-related signaling pathways. In this chapter, critical check-points within the cross-talk between neuron and protein kinases have been defined regarding the initiation and progression of AD. In this context, amyloid cascade hypothesis, neuroinflammation, oxidative stress, granulovacuolar degeneration, loss of Wnt signaling, Abeta-related synaptic alterations, prolonged calcium ions overload and NMDAR-related synaptotoxicity, damage signals hypothesis and type-3 diabetes are discussed briefly.In addition to clinical perspective of AD pathology, recommendations that might be effective in the treatment of AD patients have been reviewed.
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Affiliation(s)
- Ayse Basak Engin
- Department of Toxicology, Faculty of Pharmacy, Gazi University, Ankara, Turkey.
| | - Atilla Engin
- Department of General Surgery, Faculty of Medicine, Gazi University, Ankara, Turkey
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17
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Neuroprotection by Neurotropin through Crosstalk of Neurotrophic and Innate Immune Receptors in PC12 Cells. Int J Mol Sci 2020; 21:ijms21186456. [PMID: 32899630 PMCID: PMC7555716 DOI: 10.3390/ijms21186456] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 08/10/2020] [Accepted: 09/02/2020] [Indexed: 12/21/2022] Open
Abstract
Infected or damaged tissues release multiple “alert” molecules such as alarmins and damage-associated molecular patterns (DAMPs) that are recognized by innate immune receptors, and induce tissue inflammation, regeneration, and repair. Recently, an extract from inflamed rabbit skin inoculated with vaccinia virus (Neurotropin®, NTP) was found to induce infarct tolerance in mice receiving permanent ischemic attack to the middle cerebral artery. Likewise, we report herein that NTP prevented the neurite retraction in PC12 cells by nerve growth factor (NGF) deprivation. This effect was accompanied by interaction of Fyn with high-affinity NGF receptor TrkA. Sucrose density gradient subcellular fractionation of NTP-treated cells showed heretofore unidentified membrane fractions with a high-buoyant density containing Trk, B subunit of cholera toxin-bound ganglioside, flotillin-1 and Fyn. Additionally, these new membrane fractions also contained Toll-like receptor 4 (TLR4). Inhibition of TLR4 function by TAK-242 prevented the formation of these unidentified membrane fractions and suppressed neuroprotection by NTP. These observations indicate that NTP controls TrkA-mediated signaling through the formation of clusters of new membrane microdomains, thus providing a platform for crosstalk between neurotrophic and innate immune receptors. Neuroprotective mechanisms through the interaction with innate immune systems may provide novel mechanism for neuroprotection.
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18
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Fantini J, Chahinian H, Yahi N. Progress toward Alzheimer's disease treatment: Leveraging the Achilles' heel of Aβ oligomers? Protein Sci 2020; 29:1748-1759. [PMID: 32567070 DOI: 10.1002/pro.3906] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Revised: 06/17/2020] [Accepted: 06/19/2020] [Indexed: 12/14/2022]
Abstract
After three decades of false hopes and failures, a pipeline of therapeutic drugs that target the actual root cause of Alzheimer's disease (AD) is now available. Challenging the old paradigm that focused on β-amyloid peptide (Aβ) aggregation in amyloid plaques, these compounds are designed to prevent the neurotoxicity of Aβ oligomers that form Ca2+ permeable pores in the membranes of brain cells. By triggering an intracellular Ca2+ overdose, Aβ oligomers induce a cascade of neurotoxic events including oxidative stress, tau hyperphosphorylation, and neuronal loss. Targeting any post-Ca2+ entry steps (e.g., tau) will not address the root cause of the disease. Thus, preventing Aβ oligomers formation and/or blocking their toxicity is by essence the best approach to stop any progression of AD. Three categories of anti-oligomer compounds are already available: antibodies, synthetic peptides, and small drugs. Independent in silico-based designs of a peptide (AmyP53) and a monoclonal antibody (PMN310) converged to identify a histidine motif (H13/H14) that is critical for oligomer neutralization. This "histidine trick" can be viewed as the Achilles' heel of Aβ in the fight against AD. Moreover, lipid rafts and especially gangliosides play a critical role in the formation and toxicity of Aβ oligomers. Recognizing AD as a membrane disorder and gangliosides as the key anti-oligomer targets will provide innovative opportunities to find an efficient cure. A "full efficient" solution would also need to be affordable to anyone, as the number of patients has been following an exponential increase, affecting every part of the globe.
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Affiliation(s)
- Jacques Fantini
- INSERM UMR_S 1072, Aix-Marseille Université, Marseille, France
| | - Henri Chahinian
- INSERM UMR_S 1072, Aix-Marseille Université, Marseille, France
| | - Nouara Yahi
- INSERM UMR_S 1072, Aix-Marseille Université, Marseille, France
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19
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Pilkington AW, Donohoe GC, Akhmedov NG, Ferrebee T, Valentine SJ, Legleiter J. Hydrogen Peroxide Modifies Aβ-Membrane Interactions with Implications for Aβ 40 Aggregation. Biochemistry 2019; 58:2893-2905. [PMID: 31187978 DOI: 10.1021/acs.biochem.9b00233] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Alzheimer's disease (AD) is pathologically characterized by the formation of extracellular senile plaques, predominately comprised of aggregated β-amyloid (Aβ), deposited in the brain. Aβ aggregation can result in a myriad of distinct aggregate species, from soluble oligomers to insoluble fibrils. Aβ strongly interacts with membranes, which can be linked to a variety of potential toxic mechanisms associated with AD. Oxidative damage accompanies the formation of Aβ aggregates, with a 10-50% proportion of Aβ aggregates being oxidized in vivo. Hydrogen peroxide (H2O2) is a reactive oxygen species implicated in a number of neurodegenerative diseases. Recent evidence has demonstrated that the H2O2 concentration fluctuates rapidly in the brain, resulting in large concentration spikes, especially in the synaptic cleft. Here, the impact of environmental H2O2 on Aβ aggregation in the presence and absence of lipid membranes is investigated. Aβ40 was exposed to H2O2, resulting in the selective oxidation of methionine 35 (Met35) to produce Aβ40Met35[O]. While oxidation mildly reduced the rate of Aβ aggregation and produced a distinct fibril morphology at high H2O2 concentrations, H2O2 had a much more pronounced impact on Aβ aggregation in the presence of total brain lipid extract vesicles. The impact of H2O2 on Aβ aggregation in the presence of lipids was associated with a reduced affinity of Aβ for the vesicle surface. However, this reduced vesicle affinity was predominately associated with lipid peroxidation rather than Aβ oxidation.
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Affiliation(s)
- Albert W Pilkington
- The C. Eugene Bennett Department of Chemistry , West Virginia University , 217 Clark Hall , Morgantown , West Virginia 26506 , United States
| | - Gregory C Donohoe
- The C. Eugene Bennett Department of Chemistry , West Virginia University , 217 Clark Hall , Morgantown , West Virginia 26506 , United States
| | - Novruz G Akhmedov
- The C. Eugene Bennett Department of Chemistry , West Virginia University , 217 Clark Hall , Morgantown , West Virginia 26506 , United States
| | - Timothy Ferrebee
- The C. Eugene Bennett Department of Chemistry , West Virginia University , 217 Clark Hall , Morgantown , West Virginia 26506 , United States
| | - Stephen J Valentine
- The C. Eugene Bennett Department of Chemistry , West Virginia University , 217 Clark Hall , Morgantown , West Virginia 26506 , United States
| | - Justin Legleiter
- The C. Eugene Bennett Department of Chemistry , West Virginia University , 217 Clark Hall , Morgantown , West Virginia 26506 , United States.,Blanchette Rockefeller Neurosciences Institutes , West Virginia University , 1 Medical Center Drive , P.O. Box 9303, Morgantown , West Virginia 26505 , United States.,Department of Neuroscience , West Virginia University , 1 Medical Center Drive , P.O. Box 9303, Morgantown , West Virginia 26505 , United States
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20
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Effect of sterol structure on ordered membrane domain (raft) stability in symmetric and asymmetric vesicles. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2019; 1861:1112-1122. [PMID: 30904407 DOI: 10.1016/j.bbamem.2019.03.012] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Revised: 03/14/2019] [Accepted: 03/15/2019] [Indexed: 12/16/2022]
Abstract
Sterol structure influences liquid ordered domains in membranes, and the dependence of biological functions on sterol structure can help identify processes dependent on ordered domains. In this study we compared the effect of sterol structure on ordered domain formation in symmetric vesicles composed of mixtures of sphingomyelin, 1, 2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) and cholesterol, and in asymmetric vesicles in which sphingomyelin was introduced into the outer leaflet of vesicles composed of DOPC and cholesterol. In most cases, sterol behavior was similar in symmetric and asymmetric vesicles, with ordered domains most strongly stabilized by 7-dehydrocholesterol (7DHC) and cholesterol, stabilized to a moderate degree by lanosterol, epicholesterol and desmosterol, and very little if at all by 4-cholesten-3-one. However, in asymmetric vesicles desmosterol stabilized ordered domain almost as well as cholesterol, and to a much greater degree than epicholesterol, so that the ability to support ordered domains decreased in the order 7-DHC > cholesterol > desmosterol > lanosterol > epicholesterol > 4-cholesten-3-one. This contrasts with values for intermediate stabilizing sterols in symmetric vesicles in which the ranking was cholesterol > lanosterol ~ desmosterol ~ epicholesterol or prior studies in which the ranking was cholesterol ~ epicholesterol > lanosterol ~ desmosterol. The reasons for these differences are discussed. Based on these results, we re-evaluated our prior studies in cells and conclude that endocytosis levels and bacterial uptake are even more closely correlated with the ability of sterols to form ordered domains than previously thought, and do not necessarily require that a sterol have a 3β-OH group.
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21
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Brás IC, Lopes LV, Outeiro TF. Sensing α-Synuclein From the Outside via the Prion Protein: Implications for Neurodegeneration. Mov Disord 2018; 33:1675-1684. [DOI: 10.1002/mds.27478] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 07/24/2018] [Accepted: 07/26/2018] [Indexed: 12/30/2022] Open
Affiliation(s)
- Inês Caldeira Brás
- Department of Experimental Neurodegeneration, Center for Nanoscale Microscopy and Molecular Physiology of the Brain, Center for Biostructural Imaging of Neurodegeneration; University Medical Center Göttingen; Göttingen Germany
| | - Luísa V. Lopes
- Instituto de Medicina Molecular, Faculdade de Medicina; Universidade de Lisboa; Lisboa Portugal
| | - Tiago Fleming Outeiro
- Department of Experimental Neurodegeneration, Center for Nanoscale Microscopy and Molecular Physiology of the Brain, Center for Biostructural Imaging of Neurodegeneration; University Medical Center Göttingen; Göttingen Germany
- CEDOC, Chronic Diseases Research Center, NOVA Medical School
- Faculdade de Ciências Médicas; Universidade Nova de Lisboa, Campo dos Mártires da Pátria; Lisboa Portugal
- Max Planck Institute for Experimental Medicine; Göttingen Germany
- Institute of Neuroscience, The Medical School; Newcastle University; Newcastle Upon Tyne UK
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22
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Phosphorylation of different tau sites during progression of Alzheimer's disease. Acta Neuropathol Commun 2018; 6:52. [PMID: 29958544 PMCID: PMC6027763 DOI: 10.1186/s40478-018-0557-6] [Citation(s) in RCA: 254] [Impact Index Per Article: 36.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Accepted: 06/19/2018] [Indexed: 11/21/2022] Open
Abstract
Alzheimer’s disease is characterized by accumulation of amyloid plaques and tau aggregates in several cortical brain regions. Tau phosphorylation causes formation of neurofibrillary tangles and neuropil threads. Phosphorylation at tau Ser202/Thr205 is well characterized since labeling of this site is used to assign Braak stage based on occurrence of neurofibrillary tangles. Only little is known about the spatial and temporal phosphorylation profile of other phosphorylated tau (ptau) sites. Here, we investigate total tau and ptau at residues Tyr18, Ser199, Ser202/Thr205, Thr231, Ser262, Ser396, Ser422 as well as amyloid-β plaques in human brain tissue of AD patients and controls. Allo- and isocortical brain regions were evaluated applying rater-independent automated quantification based on digital image analysis. We found that the level of ptau at several residues, like Ser199, Ser202/Thr205, and Ser422 was similar in healthy controls and Braak stages I to IV but was increased in Braak stage V/VI throughout the entire isocortex and transentorhinal cortex. Quantification of ThioS-stained plaques showed a similar pattern. Only tau phosphorylation at Tyr18 and Thr231 was already significantly increased in the transentorhinal region at Braak stage III/IV and hence showed a progressive increase with increasing Braak stages. Additionally, the increase in phosphorylation relative to controls was highest at Tyr18, Thr231 and Ser199. By contrast, Ser396 tau and Ser262 tau showed only a weak phosphorylation in all analyzed brain regions and only minor progression. Our results suggest that the ptau burden in the isocortex is comparable between all analyzed ptau sites when using a quantitative approach while levels of ptau at Tyr18 or Thr231 in the transentorhinal region are different between all Braak stages. Hence these sites could be crucial in the pathogenesis of AD already at early stages and therefore represent putative novel therapeutic targets.
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α-synuclein interacts with PrP C to induce cognitive impairment through mGluR5 and NMDAR2B. Nat Neurosci 2017; 20:1569-1579. [PMID: 28945221 DOI: 10.1038/nn.4648] [Citation(s) in RCA: 208] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 08/21/2017] [Indexed: 12/20/2022]
Abstract
Synucleinopathies, such as Parkinson's disease and dementia with Lewy bodies, are neurodegenerative disorders that are characterized by the accumulation of α-synuclein (aSyn) in intracellular inclusions known as Lewy bodies. Prefibrillar soluble aSyn oligomers, rather than larger inclusions, are currently considered to be crucial species underlying synaptic dysfunction. We identified the cellular prion protein (PrPC) as a key mediator in aSyn-induced synaptic impairment. The aSyn-associated impairment of long-term potentiation was blocked in Prnp null mice and rescued following PrPC blockade. We found that extracellular aSyn oligomers formed a complex with PrPC that induced the phosphorylation of Fyn kinase via metabotropic glutamate receptors 5 (mGluR5). aSyn engagement of PrPC and Fyn activated NMDA receptor (NMDAR) and altered calcium homeostasis. Blockade of mGluR5-evoked phosphorylation of NMDAR in aSyn transgenic mice rescued synaptic and cognitive deficits, supporting the hypothesis that a receptor-mediated mechanism, independent of pore formation and membrane leakage, is sufficient to trigger early synaptic damage induced by extracellular aSyn.
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West E, Osborne C, Bate C. The cholesterol ester cycle regulates signalling complexes and synapse damage caused by amyloid-β. J Cell Sci 2017; 130:3050-3059. [PMID: 28760925 DOI: 10.1242/jcs.205484] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Accepted: 07/26/2017] [Indexed: 02/01/2023] Open
Abstract
Cholesterol is required for the formation and function of some signalling platforms. In synaptosomes, amyloid-β (Aβ) oligomers, the causative agent in Alzheimer's disease, bind to cellular prion proteins (PrPC) resulting in increased cholesterol concentrations, translocation of cytoplasmic phospholipase A2 (cPLA2, also known as PLA2G4A) to lipid rafts, and activation of cPLA2 The formation of Aβ-PrPC complexes is controlled by the cholesterol ester cycle. In this study, Aβ activated cholesterol ester hydrolases, which released cholesterol from stores of cholesterol esters and stabilised Aβ-PrPC complexes, resulting in activated cPLA2 Conversely, cholesterol esterification reduced cholesterol concentrations causing the dispersal of Aβ-PrPC complexes. In cultured neurons, the cholesterol ester cycle regulated Aβ-induced synapse damage; cholesterol ester hydrolase inhibitors protected neurons, while inhibition of cholesterol esterification significantly increased Aβ-induced synapse damage. An understanding of the molecular mechanisms involved in the dispersal of signalling complexes is important as failure to deactivate signalling pathways can lead to pathology. This study demonstrates that esterification of cholesterol is a key factor in the dispersal of Aβ-induced signalling platforms involved in the activation of cPLA2 and synapse degeneration.
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Affiliation(s)
- Ewan West
- Department of Pathology and Pathogen Biology, Royal Veterinary College, Hawkshead Lane, North Mymms, Herts, AL9 7TA, UK
| | - Craig Osborne
- Department of Pathology and Pathogen Biology, Royal Veterinary College, Hawkshead Lane, North Mymms, Herts, AL9 7TA, UK
| | - Clive Bate
- Department of Pathology and Pathogen Biology, Royal Veterinary College, Hawkshead Lane, North Mymms, Herts, AL9 7TA, UK
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Norambuena A, Wallrabe H, McMahon L, Silva A, Swanson E, Khan SS, Baerthlein D, Kodis E, Oddo S, Mandell JW, Bloom GS. mTOR and neuronal cell cycle reentry: How impaired brain insulin signaling promotes Alzheimer's disease. Alzheimers Dement 2017; 13:152-167. [PMID: 27693185 PMCID: PMC5318248 DOI: 10.1016/j.jalz.2016.08.015] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Accepted: 08/17/2016] [Indexed: 12/30/2022]
Abstract
A major obstacle to presymptomatic diagnosis and disease-modifying therapy for Alzheimer's disease (AD) is inadequate understanding of molecular mechanisms of AD pathogenesis. For example, impaired brain insulin signaling is an AD hallmark, but whether and how it might contribute to the synaptic dysfunction and neuron death that underlie memory and cognitive impairment has been mysterious. Neuron death in AD is often caused by cell cycle reentry (CCR) mediated by amyloid-β oligomers (AβOs) and tau, the precursors of plaques and tangles. We now report that CCR results from AβO-induced activation of the protein kinase complex, mTORC1, at the plasma membrane and mTORC1-dependent tau phosphorylation, and that CCR can be prevented by insulin-stimulated activation of lysosomal mTORC1. AβOs were also shown previously to reduce neuronal insulin signaling. Our data therefore indicate that the decreased insulin signaling provoked by AβOs unleashes their toxic potential to cause neuronal CCR, and by extension, neuron death.
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Affiliation(s)
- Andrés Norambuena
- Department of Biology, University of Virginia, Charlottesville, VA, USA.
| | - Horst Wallrabe
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Lloyd McMahon
- Department of Cell Biology, University of Virginia, Charlottesville, VA, USA
| | - Antonia Silva
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Eric Swanson
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Shahzad S Khan
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Daniel Baerthlein
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Erin Kodis
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Salvatore Oddo
- Neurodegenerative Disease Research Center, Biodesign Institute, School of Life Sciences, Arizona State University, Tempe, AZ, USA
| | - James W Mandell
- Department of Pathology, University of Virginia, Charlottesville, VA, USA
| | - George S Bloom
- Department of Biology, University of Virginia, Charlottesville, VA, USA; Department of Cell Biology, University of Virginia, Charlottesville, VA, USA; Department of Neuroscience, University of Virginia, Charlottesville, VA, USA.
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26
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St. Clair JR, Wang Q, Li G, London E. Preparation and Physical Properties of Asymmetric Model Membrane Vesicles. SPRINGER SERIES IN BIOPHYSICS 2017. [DOI: 10.1007/978-981-10-6244-5_1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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27
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Eitan E, Hutchison ER, Marosi K, Comotto J, Mustapic M, Nigam SM, Suire C, Maharana C, Jicha GA, Liu D, Machairaki V, Witwer KW, Kapogiannis D, Mattson MP. Extracellular Vesicle-Associated Aβ Mediates Trans-Neuronal Bioenergetic and Ca 2+-Handling Deficits in Alzheimer's Disease Models. NPJ Aging Mech Dis 2016; 2:16019. [PMID: 27928512 PMCID: PMC5137253 DOI: 10.1038/npjamd.2016.19] [Citation(s) in RCA: 103] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Revised: 04/21/2016] [Accepted: 06/05/2016] [Indexed: 12/19/2022] Open
Abstract
Alzheimer's Disease (AD) is an age-related neurodegenerative disorder in which aggregation-prone neurotoxic amyloid β-peptide (Aβ) accumulates in the brain. Extracellular vesicles (EVs) are small 50-150 nanometer membrane vesicles that have recently been implicated in the prion-like spread of self-aggregating proteins. Here we report that EVs isolated from AD patient CSF and plasma, from the plasma of two AD mouse models, and from the medium of neural cells expressing familial AD presenilin 1 mutations, destabilize neuronal Ca2+ homeostasis, impair mitochondrial function, and sensitize neurons to excitotoxicity. EVs contain a relatively low amount of Aβ but have an increased Aβ42/ Aβ40 ratio; the majority of Aβ is located on the surface of the EVs. Impairment of lysosome function results in increased generation EVs with elevated Aβ42 levels. EVs may mediate transcellular spread of pathogenic Aβ species and that impair neuronal Ca2+ handling and mitochondrial function, and may thereby render neurons vulnerable to excitotoxicity.
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Affiliation(s)
- Erez Eitan
- Laboratory of Neurosciences, National Institute on Aging, NIH, Baltimore, MD, USA
| | - Emmette R Hutchison
- Laboratory of Neurosciences, National Institute on Aging, NIH, Baltimore, MD, USA
| | - Krisztina Marosi
- Laboratory of Neurosciences, National Institute on Aging, NIH, Baltimore, MD, USA
| | - James Comotto
- Laboratory of Neurosciences, National Institute on Aging, NIH, Baltimore, MD, USA
| | - Maja Mustapic
- Laboratory of Neurosciences, National Institute on Aging, NIH, Baltimore, MD, USA
| | - Saket M Nigam
- Laboratory of Neurosciences, National Institute on Aging, NIH, Baltimore, MD, USA
| | - Caitlin Suire
- Laboratory of Neurosciences, National Institute on Aging, NIH, Baltimore, MD, USA
| | - Chinmoyee Maharana
- Laboratory of Neurosciences, National Institute on Aging, NIH, Baltimore, MD, USA
| | - Gregory A Jicha
- Sanders-Brown Center on Aging, and Department of Neurology, University of Kentucky College of Medicine, Lexington, KY, USA
| | - Dong Liu
- Laboratory of Neurosciences, National Institute on Aging, NIH, Baltimore, MD, USA
| | - Vasiliki Machairaki
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Kenneth W Witwer
- Department of Molecular and Comparative Pathobiology and Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | | | - Mark P Mattson
- Laboratory of Neurosciences, National Institute on Aging, NIH, Baltimore, MD, USA
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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28
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Arendt T, Stieler JT, Holzer M. Tau and tauopathies. Brain Res Bull 2016; 126:238-292. [PMID: 27615390 DOI: 10.1016/j.brainresbull.2016.08.018] [Citation(s) in RCA: 429] [Impact Index Per Article: 47.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Revised: 08/31/2016] [Accepted: 08/31/2016] [Indexed: 12/11/2022]
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29
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Glimepiride protects neurons against amyloid-β-induced synapse damage. Neuropharmacology 2016; 101:225-36. [DOI: 10.1016/j.neuropharm.2015.09.030] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Revised: 08/04/2015] [Accepted: 09/28/2015] [Indexed: 12/30/2022]
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30
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Bukar Maina M, Al-Hilaly YK, Serpell LC. Nuclear Tau and Its Potential Role in Alzheimer's Disease. Biomolecules 2016; 6:9. [PMID: 26751496 PMCID: PMC4808803 DOI: 10.3390/biom6010009] [Citation(s) in RCA: 100] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Revised: 12/16/2015] [Accepted: 12/23/2015] [Indexed: 12/14/2022] Open
Abstract
Tau protein, found in both neuronal and non-neuronal cells, forms aggregates in neurons that constitutes one of the hallmarks of Alzheimer’s disease (AD). For nearly four decades, research efforts have focused more on tau’s role in physiology and pathology in the context of the microtubules, even though, for over three decades, tau has been localised in the nucleus and the nucleolus. Its nuclear and nucleolar localisation had stimulated many questions regarding its role in these compartments. Data from cell culture, mouse brain, and the human brain suggests that nuclear tau could be essential for genome defense against cellular distress. However, its nature of translocation to the nucleus, its nuclear conformation and interaction with the DNA and other nuclear proteins highly suggest it could play multiple roles in the nucleus. To find efficient tau-based therapies, there is a need to understand more about the functional relevance of the varied cellular distribution of tau, identify whether specific tau transcripts or isoforms could predict tau’s localisation and function and how they are altered in diseases like AD. Here, we explore the cellular distribution of tau, its nuclear localisation and function and its possible involvement in neurodegeneration.
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Affiliation(s)
- Mahmoud Bukar Maina
- School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9QG, East Sussex, UK.
- Department of Human Anatomy, College of Medical Science, Gombe State University, Gombe 760, Nigeria.
| | - Youssra K Al-Hilaly
- School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9QG, East Sussex, UK.
- Chemistry Department, College of Sciences, Al-Mustansiriyah University, Baghdad, Iraq.
| | - Louise C Serpell
- School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9QG, East Sussex, UK.
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31
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Amemori T, Jendelova P, Ruzicka J, Urdzikova LM, Sykova E. Alzheimer's Disease: Mechanism and Approach to Cell Therapy. Int J Mol Sci 2015; 16:26417-51. [PMID: 26556341 PMCID: PMC4661820 DOI: 10.3390/ijms161125961] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Revised: 10/26/2015] [Accepted: 10/26/2015] [Indexed: 12/19/2022] Open
Abstract
Alzheimer’s disease (AD) is the most common form of dementia. The risk of AD increases with age. Although two of the main pathological features of AD, amyloid plaques and neurofibrillary tangles, were already recognized by Alois Alzheimer at the beginning of the 20th century, the pathogenesis of the disease remains unsettled. Therapeutic approaches targeting plaques or tangles have not yet resulted in satisfactory improvements in AD treatment. This may, in part, be due to early-onset and late-onset AD pathogenesis being underpinned by different mechanisms. Most animal models of AD are generated from gene mutations involved in early onset familial AD, accounting for only 1% of all cases, which may consequently complicate our understanding of AD mechanisms. In this article, the authors discuss the pathogenesis of AD according to the two main neuropathologies, including senescence-related mechanisms and possible treatments using stem cells, namely mesenchymal and neural stem cells.
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Affiliation(s)
- Takashi Amemori
- Department of Neuroscience, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Videnska 1083, 142 20 Prague 4, Czech Republic.
| | - Pavla Jendelova
- Department of Neuroscience, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Videnska 1083, 142 20 Prague 4, Czech Republic.
- Department of Neuroscience, 2nd Faculty of Medicine, Charles University, V Uvalu 84, 150 06 Prague 5, Czech Republic.
| | - Jiri Ruzicka
- Department of Neuroscience, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Videnska 1083, 142 20 Prague 4, Czech Republic.
| | - Lucia Machova Urdzikova
- Department of Neuroscience, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Videnska 1083, 142 20 Prague 4, Czech Republic.
| | - Eva Sykova
- Department of Neuroscience, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Videnska 1083, 142 20 Prague 4, Czech Republic.
- Department of Neuroscience, 2nd Faculty of Medicine, Charles University, V Uvalu 84, 150 06 Prague 5, Czech Republic.
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32
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Williams TL, Urbanc B, Marshall KE, Vadukul DM, Jenkins ATA, Serpell LC. Europium as an inhibitor of Amyloid-β(1-42) induced membrane permeation. FEBS Lett 2015; 589:3228-36. [PMID: 26450778 PMCID: PMC4641243 DOI: 10.1016/j.febslet.2015.09.027] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 09/16/2015] [Accepted: 09/25/2015] [Indexed: 11/25/2022]
Abstract
Europium ions complex with GM1 gangliosides in phospholipid membranes. Europium ions cause inhibition Aβ–membrane interactions. Europium blocks an Aβ receptor protecting against membrane permeation. Discrete Aβ binding events correlate to specific membrane permeation events.
Soluble Amyloid-beta (Aβ) oligomers are a source of cytotoxicity in Alzheimer’s disease (AD). The toxicity of Aβ oligomers may arise from their ability to interact with and disrupt cellular membranes mediated by GM1 ganglioside receptors within these membranes. Therefore, inhibition of Aβ–membrane interactions could provide a means of preventing the toxicity associated with Aβ. Here, using Surface Plasmon field-enhanced Fluorescence Spectroscopy, we determine that the lanthanide, Europium III chloride (Eu3+), strongly binds to GM1 ganglioside-containing membranes and prevents the interaction with Aβ42 leading to a loss of the peptides ability to cause membrane permeation. Here we discuss the molecular mechanism by which Eu3+ inhibits Aβ42-membrane interactions and this may lead to protection of membrane integrity against Aβ42 induced toxicity.
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Affiliation(s)
- Thomas L Williams
- School of Life Sciences, University of Sussex, Falmer, East Sussex BN1 9QG, UK; Physics Department, Drexel University, Philadelphia, PA 19104, USA; School of Medicine, Case Western Reserve University, Cleveland, OH 44106, USA.
| | - Brigita Urbanc
- Physics Department, Drexel University, Philadelphia, PA 19104, USA
| | - Karen E Marshall
- School of Life Sciences, University of Sussex, Falmer, East Sussex BN1 9QG, UK
| | - Devkee M Vadukul
- School of Life Sciences, University of Sussex, Falmer, East Sussex BN1 9QG, UK
| | | | - Louise C Serpell
- School of Life Sciences, University of Sussex, Falmer, East Sussex BN1 9QG, UK.
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33
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Bisel B, Pavone FS, Calamai M. GM1 and GM2 gangliosides: recent developments. Biomol Concepts 2015; 5:87-93. [PMID: 25372744 DOI: 10.1515/bmc-2013-0039] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Accepted: 01/08/2014] [Indexed: 11/15/2022] Open
Abstract
GM1 and GM2 gangliosides are important components of the cell membrane and play an integral role in cell signaling and metabolism. In this conceptual overview, we discuss recent developments in our understanding of the basic biological functions of GM1 and GM2 and their involvement in several diseases. In addition to a well-established spectrum of disorders known as gangliosidoses, such as Tay-Sachs disease, more and more evidence points at an involvement of GM1 in Alzheimer's and Parkinson's diseases. New emerging methodologies spanning from single-molecule imaging in vivo to simulations in silico have complemented standard studies based on ganglioside extraction.
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34
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Bate C. Enhanced neuronal degradation of amyloid-β oligomers allows synapse regeneration. Neural Regen Res 2015; 10:700-1. [PMID: 26109937 PMCID: PMC4468754 DOI: 10.4103/1673-5374.156955] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/13/2015] [Indexed: 11/30/2022] Open
Affiliation(s)
- Clive Bate
- Department of Pathology and Pathogen Biology, Royal Veterinary College, Hawkshead Lane, North Mymms, Herts, AL9 7TA, UK
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35
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Williams RSB, Bate C. An in vitro model for synaptic loss in neurodegenerative diseases suggests a neuroprotective role for valproic acid via inhibition of cPLA2 dependent signalling. Neuropharmacology 2015; 101:566-75. [PMID: 26116815 DOI: 10.1016/j.neuropharm.2015.06.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Revised: 06/10/2015] [Accepted: 06/16/2015] [Indexed: 12/28/2022]
Abstract
Many neurodegenerative diseases present the loss of synapses as a common pathological feature. Here we have employed an in vitro model for synaptic loss to investigate the molecular mechanism of a therapeutic treatment, valproic acid (VPA). We show that amyloid-β (Aβ), isolated from patient tissue and thought to be the causative agent of Alzheimer's disease, caused the loss of synaptic proteins including synaptophysin, synapsin-1 and cysteine-string protein from cultured mouse neurons. Aβ-induced synapse damage was reduced by pre-treatment with physiologically relevant concentrations of VPA (10 μM) and a structural variant propylisopropylacetic acid (PIA). These drugs also reduced synaptic damage induced by other neurodegenerative-associated proteins α-synuclein, linked to Lewy body dementia and Parkinson's disease, and the prion-derived peptide PrP82-146. Consistent with these effects, synaptic vesicle recycling was also inhibited by these proteins and protected by VPA and PIA. We show a mechanism for this damage through aberrant activation of cytoplasmic phospholipase A2 (cPLA2) that is reduced by both drugs. Furthermore, Aβ-dependent cPLA2 activation correlates with its accumulation in lipid rafts, and is likely to be caused by elevated cholesterol (stabilising rafts) and decreased cholesterol ester levels, and this mechanism is reduced by VPA and PIA. Such observations suggest that VPA and PIA may provide protection against synaptic damage that occurs during Alzheimer's and Parkinson's and prion diseases.
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Affiliation(s)
- Robin S B Williams
- Centre for Biomedical Sciences, School of Biological Sciences, Royal Holloway University of London, Egham, Surrey, TW20 0EX, UK
| | - Clive Bate
- Department of Pathology and Pathogen Biology, Royal Veterinary College, Hawkshead Lane, North Mymms, Herts, AL9 7TA, UK.
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36
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Zhu D, Bungart BL, Yang X, Zhumadilov Z, Lee JCM, Askarova S. Role of membrane biophysics in Alzheimer's-related cell pathways. Front Neurosci 2015; 9:186. [PMID: 26074758 PMCID: PMC4444756 DOI: 10.3389/fnins.2015.00186] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Accepted: 05/11/2015] [Indexed: 01/04/2023] Open
Abstract
Cellular membrane alterations are commonly observed in many diseases, including Alzheimer's disease (AD). Membrane biophysical properties, such as membrane molecular order, membrane fluidity, organization of lipid rafts, and adhesion between membrane and cytoskeleton, play an important role in various cellular activities and functions. While membrane biophysics impacts a broad range of cellular pathways, this review addresses the role of membrane biophysics in amyloid-β peptide aggregation, Aβ-induced oxidative pathways, amyloid precursor protein processing, and cerebral endothelial functions in AD. Understanding the mechanism(s) underlying the effects of cell membrane properties on cellular processes should shed light on the development of new preventive and therapeutic strategies for this devastating disease.
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Affiliation(s)
- Donghui Zhu
- Department of Chemical, Biological and Bioengineering, North Carolina A&T State UniversityGreensboro, NC, USA
| | - Brittani L. Bungart
- Indiana University School of Medicine Medical Scientist Training Program, Indiana University School of MedicineIndianapolis, IN, USA
| | - Xiaoguang Yang
- Department of Clinical Neuroscience and Rehabilitation, Institute of Neuroscience and Physiology, Sahlgrenska Academy at University of GothenburgGothenburg, Sweden
- The Hope Center for Neurological Disorders and Department of Neurology, Washington University School of MedicineSt. Louis, MO, USA
| | - Zhaxybay Zhumadilov
- Department of Bioengineering and Regenerative Medicine, Center for Life Sciences, Nazarbayev UniversityAstana, Kazakhstan
| | - James C-M. Lee
- Department of Bioengineering, University of Illinois at ChicagoChicago, IL, USA
| | - Sholpan Askarova
- Department of Bioengineering and Regenerative Medicine, Center for Life Sciences, Nazarbayev UniversityAstana, Kazakhstan
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37
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Sharma N, Singh V, Shyma KP. Role of parasitic vaccines in integrated control of parasitic diseases in livestock. Vet World 2015; 8:590-8. [PMID: 27047140 PMCID: PMC4774718 DOI: 10.14202/vetworld.2015.590-598] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Revised: 03/26/2015] [Accepted: 03/31/2015] [Indexed: 11/18/2022] Open
Abstract
Parasitic infections adversely affect animal’s health and threaten profitable animal production, thus affecting the economy of our country. These infections also play a major role in the spread of zoonotic diseases. Parasitic infections cause severe morbidity and mortality in animals especially those affecting the gastrointestinal system and thus affect the economy of livestock owner by decreasing the ability of the farmer to produce economically useful animal products. Due to all these reasons proper control of parasitic infection is critically important for sustained animal production. The most common and regularly used method to control parasitic infection is chemotherapy, which is very effective but has several disadvantages like drug resistance and drug residues. Integrated approaches to control parasitic infections should be formulated including grazing management, biological control, genetic resistance of hosts, and parasitic vaccines. India ranks first in cattle and buffalo population, but the majority of livestock owners have fewer herds, so other measures like grazing management, biological control, genetic resistance of hosts are not much practical to use. The most sustainable and economical approach to control parasitic infection in our country is to vaccinate animals, although vaccines increase the initial cost, but the immunity offered by the vaccine are long lived. Thus, vaccination of animals for various clinical, chronic, subclinical parasitic infections will be a cheaper and effective alternative to control parasitic infection for long time and improve animal production.
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Affiliation(s)
- Neelu Sharma
- Department of Veterinary Parasitology, College of Veterinary Science and Animal Husbandry, Sardarkrushinagar Dantiwada Agricultural University, Sardarkrushinagar - 385 506, Gujarat, India
| | - Veer Singh
- Department of Veterinary Parasitology, College of Veterinary Science and Animal Husbandry, Sardarkrushinagar Dantiwada Agricultural University, Sardarkrushinagar - 385 506, Gujarat, India
| | - K P Shyma
- Department of Veterinary Parasitology, College of Veterinary Science and Animal Husbandry, Sardarkrushinagar Dantiwada Agricultural University, Sardarkrushinagar - 385 506, Gujarat, India
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38
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Uptake of raft components into amyloid β-peptide aggregates and membrane damage. Anal Biochem 2015; 481:18-26. [PMID: 25908557 DOI: 10.1016/j.ab.2015.04.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 03/13/2015] [Accepted: 04/12/2015] [Indexed: 01/26/2023]
Abstract
Amyloid aggregation and deposition of amyloid β-peptide (Aβ) are pathologic characteristics of Alzheimer's disease (AD). Recent reports have shown that the association of Aβ with membranes containing ganglioside GM1 (GM1) plays a pivotal role in amyloid deposition and the pathogenesis of AD. However, the molecular interactions responsible for membrane damage associated with Aβ deposition are not fully understood. In this study, we microscopically observed amyloid aggregation of Aβ in the presence of lipid vesicles and on a substrate-supported planar membrane containing raft components and GM1. The experimental system enabled us to observe lipid-associated aggregation of Aβ, uptake of the raft components into Aβ aggregates, and relevant membrane damage. The results indicate that uptake of raft components from the membrane into Aβ deposits induces macroscopic heterogeneity of the membrane structure.
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Nishikawa T, Takahashi T, Nakamori M, Yamazaki Y, Kurashige T, Nagano Y, Nishida Y, Izumi Y, Matsumoto M. Phosphatidylinositol-4,5-bisphosphate is enriched in granulovacuolar degeneration bodies and neurofibrillary tangles. Neuropathol Appl Neurobiol 2015; 40:489-501. [PMID: 23631697 PMCID: PMC4298759 DOI: 10.1111/nan.12056] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2012] [Accepted: 04/24/2013] [Indexed: 11/29/2022]
Abstract
Aims Among the pathological findings in Alzheimer’s disease (AD), the temporal and spatial profiles of granulovacuolar degeneration (GVD) bodies are characteristic in that they seem to be related to those of neurofibrillary tangles (NFTs), suggesting a common mechanism underlying the pathogenesis of these structures. Flotillin-1, a marker of lipid rafts, accumulates in lysosomes of tangle-bearing neurones in AD patients. In addition, recent reports have shown that GVD bodies accumulate at the nexus of the autophagic and endocytic pathways. The aim of this study was to elucidate the distribution of the lipid component of lipid rafts, phosphatidylinositol-4,5-bisphosphate [PtdIns(4,5)P2], in AD and other neurodegenerative disorders. Methods We compared PtdIns(4,5)P2 immunoreactivity in the hippocampus, entorhinal cortex and neocortex of five AD cases, 17 cases of other neurodegenerative disorders and four controls. In addition, we performed double staining using markers of GVD, NFTs and lipid rafts for further characterization. Results Immunohistochemical analysis revealed that PtdIns(4,5)P2 was selectively enriched in GVD bodies and NFTs. Although immunoreactivity for PtdIns(4,5)P2 was also evident in NFTs composed of hyperphosphorylated tau, PtdIns(4,5)P2 was segregated from phosphorylated tau within NFTs by double immunofluorescence staining. In contrast, PtdIns(4,5)P2 colocalized with the lipid raft markers flotillin-1 and annexin 2, within GVD bodies and NFTs. Conclusions These results suggest that lipid raft components including PtdIns(4,5)P2 play a role in the formation of both GVD bodies and NFTs.
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Affiliation(s)
- Tomokazu Nishikawa
- Department of Clinical Neuroscience and Therapeutics, Hiroshima University Graduate School of Biomedical and Health Sciences
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Singh S, Trikha S, Bhowmick DC, Sarkar AA, Jeremic AM. Role of Cholesterol and Phospholipids in Amylin Misfolding, Aggregation and Etiology of Islet Amyloidosis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2015; 855:95-116. [PMID: 26149927 DOI: 10.1007/978-3-319-17344-3_4] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Amyloidosis is a biological event in which proteins undergo structural transitions from soluble monomers and oligomers to insoluble fibrillar aggregates that are often toxic to cells. Exactly how amyloid proteins, such as the pancreatic hormone amylin, aggregate and kill cells is still unclear. Islet amyloid polypeptide, or amylin, is a recently discovered hormone that is stored and co-released with insulin from pancreatic islet β-cells. The pathology of type 2 diabetes mellitus (T2DM) is characterized by an excessive extracellular and intracellular accumulation of toxic amylin species, soluble oligomers and insoluble fibrils, in islets, eventually leading to β-cell loss. Obesity and elevated serum cholesterol levels are additional risk factors implicated in the development of T2DM. Because the homeostatic balance between cholesterol synthesis and uptake is lost in diabetics, and amylin aggregation is a hallmark of T2DM, this chapter focuses on the biophysical and cell biology studies exploring molecular mechanisms by which cholesterol and phospholipids modulate secondary structure, folding and aggregation of human amylin and other amyloid proteins on membranes and in cells. Amylin turnover and toxicity in pancreatic cells and the regulatory role of cholesterol in these processes are also discussed.
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Affiliation(s)
- Sanghamitra Singh
- Department of Biological Sciences, The George Washington University, 2023 G Street NW, Washington, DC, 20052, USA
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41
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Kam TI, Gwon Y, Jung YK. Amyloid beta receptors responsible for neurotoxicity and cellular defects in Alzheimer's disease. Cell Mol Life Sci 2014; 71:4803-13. [PMID: 25151011 PMCID: PMC11113744 DOI: 10.1007/s00018-014-1706-0] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Revised: 07/24/2014] [Accepted: 08/13/2014] [Indexed: 01/11/2023]
Abstract
Alzheimer's disease (AD) is the most common neurodegenerative disease. Although a major cause of AD is the accumulation of amyloid-β (Aβ) peptide that induces neuronal loss and cognitive impairments, our understanding of its neurotoxic mechanisms is limited. Recent studies have identified putative Aβ-binding receptors that mediate Aβ neurotoxicity in cells and models of AD. Once Aβ interacts with a receptor, a toxic signal is transduced into neurons, resulting in cellular defects including endoplasmic reticulum stress and mitochondrial dysfunction. In addition, Aβ can also be internalized into neurons through unidentified Aβ receptors and induces malfunction of subcellular organelles, which explains some part of Aβ neurotoxicity. Understanding the neurotoxic signaling initiated by Aβ-receptor binding and cellular defects provide insight into new therapeutic windows for AD. In the present review, we summarize the findings on Aβ-binding receptors and the neurotoxicity of oligomeric Aβ.
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Affiliation(s)
- Tae-In Kam
- Global Research Laboratory, School of Biological Sciences, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 151-747 Korea
| | - Youngdae Gwon
- Global Research Laboratory, School of Biological Sciences, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 151-747 Korea
| | - Yong-Keun Jung
- Global Research Laboratory, School of Biological Sciences, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 151-747 Korea
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Shah A, Chen D, Boda AR, Foster LJ, Davis MJ, Hill MM. RaftProt: mammalian lipid raft proteome database. Nucleic Acids Res 2014; 43:D335-8. [PMID: 25392410 PMCID: PMC4383944 DOI: 10.1093/nar/gku1131] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
RaftProt (http://lipid-raft-database.di.uq.edu.au/) is a database of mammalian lipid raft-associated proteins as reported in high-throughput mass spectrometry studies. Lipid rafts are specialized membrane microdomains enriched in cholesterol and sphingolipids thought to act as dynamic signalling and sorting platforms. Given their fundamental roles in cellular regulation, there is a plethora of information on the size, composition and regulation of these membrane microdomains, including a large number of proteomics studies. To facilitate the mining and analysis of published lipid raft proteomics studies, we have developed a searchable database RaftProt. In addition to browsing the studies, performing basic queries by protein and gene names, searching experiments by cell, tissue and organisms; we have implemented several advanced features to facilitate data mining. To address the issue of potential bias due to biochemical preparation procedures used, we have captured the lipid raft preparation methods and implemented advanced search option for methodology and sample treatment conditions, such as cholesterol depletion. Furthermore, we have identified a list of high confidence proteins, and enabled searching only from this list of likely bona fide lipid raft proteins. Given the apparent biological importance of lipid raft and their associated proteins, this database would constitute a key resource for the scientific community.
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Affiliation(s)
- Anup Shah
- The University of Queensland Diamantina Institute, The University of Queensland, Translational Research Institute, Brisbane, QLD, Australia
| | - David Chen
- School of Information and Communication Technology, Griffith University, Brisbane, QLD, Australia
| | - Akash R Boda
- The University of Queensland Diamantina Institute, The University of Queensland, Translational Research Institute, Brisbane, QLD, Australia
| | - Leonard J Foster
- Centre for High-Throughput Biology, University of British Columbia, British Columbia, Canada
| | - Melissa J Davis
- Systems Biology Laboratory, Melbourne School of Engineering, The University of Melbourne, Parkville, VIC, Australia
| | - Michelle M Hill
- The University of Queensland Diamantina Institute, The University of Queensland, Translational Research Institute, Brisbane, QLD, Australia
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Zhou X, Yang C, Liu Y, Li P, Yang H, Dai J, Qu R, Yuan L. Lipid rafts participate in aberrant degradative autophagic-lysosomal pathway of amyloid-beta peptide in Alzheimer's disease. Neural Regen Res 2014; 9:92-100. [PMID: 25206748 PMCID: PMC4146310 DOI: 10.4103/1673-5374.125335] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/25/2013] [Indexed: 11/04/2022] Open
Abstract
Amyloid-beta peptide is the main component of amyloid plaques, which are found in Alzheimer's disease. The generation and deposition of amyloid-beta is one of the crucial factors for the onset and progression of Alzheimer's disease. Lipid rafts are glycolipid-rich liquid domains of the plasma membrane, where certain types of protein tend to aggregate and intercalate. Lipid rafts are involved in the generation of amyloid-beta oligomers and the formation of amyloid-beta peptides. In this paper, we review the mechanism by which lipid rafts disturb the aberrant degradative autophagic-lysosomal pathway of amyloid-beta, which plays an important role in the pathological process of Alzheimer's disease. Moreover, we describe this mechanism from the view of the Two-system Theory of fasciology and thus, suggest that lipid rafts may be a new target of Alzheimer's disease treatment.
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Affiliation(s)
- Xin Zhou
- Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guang-dong Province, China
| | - Chun Yang
- Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guang-dong Province, China
| | - Yufeng Liu
- Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guang-dong Province, China
| | - Peng Li
- Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guang-dong Province, China
| | - Huiying Yang
- Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guang-dong Province, China
| | - Jingxing Dai
- Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guang-dong Province, China
| | - Rongmei Qu
- Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guang-dong Province, China
| | - Lin Yuan
- Department of Human Anatomy, Histology and Embryology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guang-dong Province, China
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Fernandez-Echevarria C, Díaz M, Ferrer I, Canerina-Amaro A, Marin R. Aβ promotes VDAC1 channel dephosphorylation in neuronal lipid rafts. Relevance to the mechanisms of neurotoxicity in Alzheimer's disease. Neuroscience 2014; 278:354-66. [PMID: 25168729 DOI: 10.1016/j.neuroscience.2014.07.079] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Revised: 07/23/2014] [Accepted: 07/24/2014] [Indexed: 11/25/2022]
Abstract
Voltage-dependent anion channel (VDAC) is a mitochondrial protein abundantly found in neuronal lipid rafts. In these membrane domains, VDAC is associated with a complex of signaling proteins that trigger neuroprotective responses. Loss of lipid raft integrity may result in disruption of multicomplex association and alteration of signaling responses that may ultimately promote VDAC activation. Some data have demonstrated that VDAC at the neuronal membrane may be involved in the mechanisms of amyloid beta (Aβ)-induced neurotoxicity, through yet unknown mechanisms. Aβ is generated from amyloid precursor protein (APP), and is released to the extracellular space where it may undergo self-aggregation. Aβ aggregate deposition in the form of senile plaques may lead to Alzheimer's disease (AD) neuropathology, although other pathological hallmarks (such as hyper-phosphorylated Tau deposition) also participate in this neurodegenerative process. The present study demonstrates that VDAC1 associates with APP and Aβ in lipid rafts of neurons. Interaction of VDAC1 with APP was observed in lipid rafts from the frontal and entorhinal cortex of human brains affected by AD at early stages (I-IV/0-B of Braak and Braak). Furthermore, Aβ exposure enhanced the dephosphorylation of VDAC1 that correlated with cell death. Both effects were reverted in the presence of tyrosine phosphatase inhibitors. VDAC1 dephosphorylation was corroborated in lipid rafts of AD brains. These results demonstrate that Aβ is involved in alterations of the phosphorylation state of VDAC in neuronal lipid rafts. Modulation of this channel may contribute to the development and progression of AD pathology.
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Affiliation(s)
- C Fernandez-Echevarria
- Laboratory of Cellular Neurobiology, Department of Physiology, University of La Laguna, School of Medicine, Sta. Cruz de Tenerife, Spain
| | - M Díaz
- Laboratory of Membrane Physiology and Biophysics, Department of Animal Biology, Faculty of Biology, University of La Laguna, Sta. Cruz de Tenerife, Spain
| | - I Ferrer
- Institute of Neuropathology, Bellvitge University Hospital, University of Barcelona, IDIBELL, CIBERNED, Hospitalet de Llobregat, Barcelona, Spain
| | - A Canerina-Amaro
- Laboratory of Cellular Neurobiology, Department of Physiology, University of La Laguna, School of Medicine, Sta. Cruz de Tenerife, Spain
| | - R Marin
- Laboratory of Cellular Neurobiology, Department of Physiology, University of La Laguna, School of Medicine, Sta. Cruz de Tenerife, Spain.
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Watt NT, Griffiths HH, Hooper NM. Lipid rafts: linking prion protein to zinc transport and amyloid-β toxicity in Alzheimer's disease. Front Cell Dev Biol 2014; 2:41. [PMID: 25364748 PMCID: PMC4206978 DOI: 10.3389/fcell.2014.00041] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Accepted: 08/05/2014] [Indexed: 01/01/2023] Open
Abstract
Dysregulation of neuronal zinc homeostasis plays a major role in many processes related to brain aging and neurodegenerative diseases, including Alzheimer's disease (AD). Yet, despite the critical role of zinc in neuronal function, the cellular mechanisms underpinning its homeostatic control are far from clear. We reported that the cellular prion protein (PrPC) is involved in the uptake of zinc into neurons. This PrPC-mediated zinc influx required the metal-binding octapeptide repeats in PrPC and the presence of the zinc permeable AMPA channel with which PrPC directly interacted. Together with the observation that PrPC is evolutionarily related to the ZIP family of zinc transporters, these studies indicate that PrPC plays a key role in neuronal zinc homeostasis. Therefore, PrPC could contribute to cognitive health and protect against age-related zinc dyshomeostasis but PrPC has also been identified as a receptor for amyloid-β oligomers which accumulate in the brains of those with AD. We propose that the different roles that PrPC has are due to its interaction with different ligands and/or co-receptors in lipid raft-based signaling/transport complexes.
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Affiliation(s)
- Nicole T Watt
- Division of Cardiovascular and Diabetes Research, Multidisciplinary Cardiovascular Research Centre, University of Leeds Leeds, UK
| | - Heledd H Griffiths
- Faculty of Medical and Human Sciences, Institute of Brain, Behaviour and Mental Health, University of Manchester Manchester, UK
| | - Nigel M Hooper
- Faculty of Medical and Human Sciences, Institute of Brain, Behaviour and Mental Health, University of Manchester Manchester, UK
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Ko HM, Lee SH, Kim KC, Joo SH, Choi WS, Shin CY. The Role of TLR4 and Fyn Interaction on Lipopolysaccharide-Stimulated PAI-1 Expression in Astrocytes. Mol Neurobiol 2014; 52:8-25. [DOI: 10.1007/s12035-014-8837-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Accepted: 07/28/2014] [Indexed: 01/05/2023]
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Vergara C, Ordóñez-Gutiérrez L, Wandosell F, Ferrer I, del Río JA, Gavín R. Role of PrP(C) Expression in Tau Protein Levels and Phosphorylation in Alzheimer's Disease Evolution. Mol Neurobiol 2014; 51:1206-20. [PMID: 24965601 DOI: 10.1007/s12035-014-8793-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Accepted: 06/15/2014] [Indexed: 10/25/2022]
Abstract
Alzheimer's disease (AD) is characterized by the presence of amyloid plaques mainly consisting of hydrophobic β-amyloid peptide (Aβ) aggregates and neurofibrillary tangles (NFTs) composed principally of hyperphosphorylated tau. Aβ oligomers have been described as the earliest effectors to negatively affect synaptic structure and plasticity in the affected brains, and cellular prion protein (PrP(C)) has been proposed as receptor for these oligomers. The most widely accepted theory holds that the toxic effects of Aβ are upstream of change in tau, a neuronal microtubule-associated protein that promotes the polymerization and stabilization of microtubules. However, tau is considered decisive for the progression of neurodegeneration, and, indeed, tau pathology correlates well with clinical symptoms such as dementia. Different pathways can lead to abnormal phosphorylation, and, as a consequence, tau aggregates into paired helical filaments (PHF) and later on into NFTs. Reported data suggest a regulatory tendency of PrP(C) expression in the development of AD, and a putative relationship between PrP(C) and tau processing is emerging. However, the role of tau/PrP(C) interaction in AD is poorly understood. In this study, we show increased susceptibility to Aβ-derived diffusible ligands (ADDLs) in neuronal primary cultures from PrP(C) knockout mice, compared to wild-type, which correlates with increased tau expression. Moreover, we found increased PrP(C) expression that paralleled with tau at early ages in an AD murine model and in early Braak stages of AD in affected individuals. Taken together, these results suggest a protective role for PrP(C) in AD by downregulating tau expression, and they point to this protein as being crucial in the molecular events that lead to neurodegeneration in AD.
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Affiliation(s)
- C Vergara
- Molecular and Cellular Neurobiotechnology, Institute for Bioengineering of Catalonia, Baldiri Reixac 15-21, 08028, Barcelona, Spain
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Hirsch TZ, Hernandez-Rapp J, Martin-Lannerée S, Launay JM, Mouillet-Richard S. PrP(C) signalling in neurons: from basics to clinical challenges. Biochimie 2014; 104:2-11. [PMID: 24952348 DOI: 10.1016/j.biochi.2014.06.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Accepted: 06/10/2014] [Indexed: 01/05/2023]
Abstract
The cellular prion protein PrP(C) was identified over twenty-five years ago as the normal counterpart of the scrapie prion protein PrP(Sc), itself the main if not the sole component of the infectious agent at the root of Transmissible Spongiform Encephalopathies (TSEs). PrP(C) is a ubiquitous cell surface protein, abundantly expressed in neurons, which constitute the targets of PrP(Sc)-mediated toxicity. Converging evidence have highlighted that neuronal, GPI-anchored PrP(C) is absolutely required for prion-induced neuropathogenesis, which warrants investigating into the normal function exerted by PrP(C) in a neuronal context. It is now well-established that PrP(C) can serve as a cell signalling molecule, able to mobilize transduction cascades in response to interactions with partners. This function endows PrP(C) with the capacity to participate in multiple neuronal processes, ranging from survival to synaptic plasticity. A diverse array of data have allowed to shed light on how this function is corrupted by PrP(Sc). Recently, amyloid Aβ oligomers, whose accumulation is associated with Alzheimer's disease (AD), were shown to similarly instigate toxic events by deviating PrP(C)-mediated signalling. Here, we provide an overview of the various signal transduction cascades ascribed to PrP(C) in neurons, summarize how their subversion by PrP(Sc) or Aβ oligomers contributes to TSE or AD neuropathogenesis and discuss the ensuing clinical implications.
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Affiliation(s)
- Théo Z Hirsch
- INSERM UMR-S1124, 75006 Paris, France; Université Paris Descartes, Sorbonne Paris Cité, UMR-S1124, 75006 Paris, France
| | - Julia Hernandez-Rapp
- INSERM UMR-S1124, 75006 Paris, France; Université Paris Descartes, Sorbonne Paris Cité, UMR-S1124, 75006 Paris, France; Université Paris Sud 11, ED419 Biosigne, 91400 Orsay, France
| | - Séverine Martin-Lannerée
- INSERM UMR-S1124, 75006 Paris, France; Université Paris Descartes, Sorbonne Paris Cité, UMR-S1124, 75006 Paris, France
| | - Jean-Marie Launay
- AP-HP Service de Biochimie, Fondation FondaMental, INSERM U942 Hôpital Lariboisière, 75010 Paris, France; Pharma Research Department, F. Hoffmann-La-Roche Ltd., CH-4070 Basel, Switzerland
| | - Sophie Mouillet-Richard
- INSERM UMR-S1124, 75006 Paris, France; Université Paris Descartes, Sorbonne Paris Cité, UMR-S1124, 75006 Paris, France.
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Tau protein modifications and interactions: their role in function and dysfunction. Int J Mol Sci 2014; 15:4671-713. [PMID: 24646911 PMCID: PMC3975420 DOI: 10.3390/ijms15034671] [Citation(s) in RCA: 266] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Revised: 02/11/2014] [Accepted: 03/04/2014] [Indexed: 01/29/2023] Open
Abstract
Tau protein is abundant in the central nervous system and involved in microtubule assembly and stabilization. It is predominantly associated with axonal microtubules and present at lower level in dendrites where it is engaged in signaling functions. Post-translational modifications of tau and its interaction with several proteins play an important regulatory role in the physiology of tau. As a consequence of abnormal modifications and expression, tau is redistributed from neuronal processes to the soma and forms toxic oligomers or aggregated deposits. The accumulation of tau protein is increasingly recognized as the neuropathological hallmark of a number of dementia disorders known as tauopathies. Dysfunction of tau protein may contribute to collapse of cytoskeleton, thereby causing improper anterograde and retrograde movement of motor proteins and their cargos on microtubules. These disturbances in intraneuronal signaling may compromise synaptic transmission as well as trophic support mechanisms in neurons.
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Simmons C, Ingham V, Williams A, Bate C. Platelet-activating factor antagonists enhance intracellular degradation of amyloid-β42 in neurons via regulation of cholesterol ester hydrolases. Alzheimers Res Ther 2014; 6:15. [PMID: 24625058 PMCID: PMC4055000 DOI: 10.1186/alzrt245] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Accepted: 02/19/2014] [Indexed: 12/26/2022]
Abstract
INTRODUCTION The progressive dementia that is characteristic of Alzheimer's disease is associated with the accumulation of amyloid-beta (Aβ) peptides in extracellular plaques and within neurons. Aβ peptides are targeted to cholesterol-rich membrane micro-domains called lipid rafts. Observations that many raft proteins undertake recycling pathways that avoid the lysosomes suggest that the accumulation of Aβ in neurons may be related to Aβ targeting lipid rafts. Here we tested the hypothesis that the degradation of Aβ by neurons could be increased by drugs affecting raft formation. METHODS Primary neurons were incubated with soluble Aβ preparations. The amounts of Aβ42 in neurons or specific cellular compartments were measured by enzyme-linked immunosorbent assay. The effects of drugs on the degradation of Aβ42 were studied. RESULTS Aβ42 was targeted to detergent-resistant, low-density membranes (lipid rafts), trafficked via a pathway that avoided the lysosomes, and was slowly degraded by neurons (half-life was greater than 5 days). The metabolism of Aβ42 was sensitive to pharmacological manipulation. In neurons treated with the cholesterol synthesis inhibitor squalestatin, less Aβ42 was found within rafts, greater amounts of Aβ42 were found in lysosomes, and the half-life of Aβ42 was reduced to less than 24 hours. Treatment with phospholipase A2 inhibitors or platelet-activating factor (PAF) antagonists had the same effects on Aβ42 metabolism in neurons as squalestatin. PAF receptors were concentrated in the endoplasmic reticulum (ER) along with enzymes that constitute the cholesterol ester cycle. The addition of PAF to ER membranes triggered activation of cholesterol ester hydrolases and the release of cholesterol from stores of cholesterol esters. An inhibitor of cholesterol ester hydrolases (diethylumbelliferyl phosphate) also increased the degradation of Aβ42 in neurons. CONCLUSIONS We conclude that the targeting of Aβ42 to rafts in normal cells is a factor that affects its degradation. Critically, pharmacological manipulation of neurons can significantly increase Aβ42 degradation. These results are consistent with the hypothesis that the Aβ-induced production of PAF controls a cholesterol-sensitive pathway that affects the cellular localization and hence the fate of Aβ42 in neurons.
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Affiliation(s)
- Charlotte Simmons
- Department of Pathology and Pathogen Biology, Royal Veterinary College, Hawkshead Lane, North Mymms, Herts AL9 7TA, UK
| | - Victoria Ingham
- Department of Pathology and Pathogen Biology, Royal Veterinary College, Hawkshead Lane, North Mymms, Herts AL9 7TA, UK
| | - Alun Williams
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 OES, UK
| | - Clive Bate
- Department of Pathology and Pathogen Biology, Royal Veterinary College, Hawkshead Lane, North Mymms, Herts AL9 7TA, UK
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