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Żukowska J, Moss SJ, Subramanian V, Acharya KR. Molecular basis of selective amyloid-β degrading enzymes in Alzheimer's disease. FEBS J 2024; 291:2999-3029. [PMID: 37622248 DOI: 10.1111/febs.16939] [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: 06/07/2023] [Revised: 07/31/2023] [Accepted: 08/22/2023] [Indexed: 08/26/2023]
Abstract
The accumulation of the small 42-residue long peptide amyloid-β (Aβ) has been proposed as a major trigger for the development of Alzheimer's disease (AD). Within the brain, the concentration of Aβ peptide is tightly controlled through production and clearance mechanisms. Substantial experimental evidence now shows that reduced levels of Aβ clearance are present in individuals living with AD. This accumulation of Aβ can lead to the formation of large aggregated amyloid plaques-one of two detectable hallmarks of the disease. Aβ-degrading enzymes (ADEs) are major players in the clearance of Aβ. Stimulating ADE activity or expression, in order to compensate for the decreased clearance in the AD phenotype, provides a promising therapeutic target. It has been reported in mice that upregulation of ADEs can reduce the levels of Aβ peptide and amyloid plaques-in some cases, this led to improved cognitive function. Among several known ADEs, neprilysin (NEP), endothelin-converting enzyme-1 (ECE-1), insulin degrading enzyme (IDE) and angiotensin-1 converting enzyme (ACE) from the zinc metalloprotease family have been identified as important. These ADEs have the capacity to digest soluble Aβ which, in turn, cannot form the toxic oligomeric species. While they are known for their amyloid degradation, they exhibit complexity through promiscuous nature and a broad range of substrates that they can degrade. This review highlights current structural and functional understanding of these key ADEs, giving some insight into the molecular interactions that leads to the hydrolysis of peptide substrates, the crucial tasks performed by them and the potential for therapeutic use in the future.
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2
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Shippy DC, Oliai SF, Ulland TK. Zinc utilization by microglia in Alzheimer's disease. J Biol Chem 2024; 300:107306. [PMID: 38648940 PMCID: PMC11103939 DOI: 10.1016/j.jbc.2024.107306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2024] [Revised: 04/10/2024] [Accepted: 04/15/2024] [Indexed: 04/25/2024] Open
Abstract
Alzheimer's disease (AD) is the most common form of dementia defined by two key pathological characteristics in the brain, amyloid-β (Aβ) plaques and neurofibrillary tangles (NFTs) composed of hyperphosphorylated tau. Microglia, the primary innate immune cells of the central nervous system (CNS), provide neuroprotection through Aβ and tau clearance but may also be neurotoxic by promoting neuroinflammation to exacerbate Aβ and tau pathogenesis in AD. Recent studies have demonstrated the importance of microglial utilization of nutrients and trace metals in controlling their activation and effector functions. Trace metals, such as zinc, have essential roles in brain health and immunity, and zinc dyshomeostasis has been implicated in AD pathogenesis. As a result of these advances, the mechanisms by which zinc homeostasis influences microglial-mediated neuroinflammation in AD is a topic of continuing interest since new strategies to treat AD are needed. Here, we review the roles of zinc in AD, including zinc activation of microglia, the associated neuroinflammatory response, and the application of these findings in new therapeutic strategies.
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Affiliation(s)
- Daniel C Shippy
- Department of Pathology and Laboratory Medicine, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin, USA
| | - Sophia F Oliai
- Department of Pathology and Laboratory Medicine, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin, USA
| | - Tyler K Ulland
- Department of Pathology and Laboratory Medicine, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin, USA; Wisconsin Alzheimer's Disease Research Center, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin, USA.
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3
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Ullah R, Lee EJ. Advances in Amyloid-β Clearance in the Brain and Periphery: Implications for Neurodegenerative Diseases. Exp Neurobiol 2023; 32:216-246. [PMID: 37749925 PMCID: PMC10569141 DOI: 10.5607/en23014] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 07/25/2023] [Accepted: 08/23/2023] [Indexed: 09/27/2023] Open
Abstract
This review examines the role of impaired amyloid-β clearance in the accumulation of amyloid-β in the brain and the periphery, which is closely associated with Alzheimer's disease (AD) and cerebral amyloid angiopathy (CAA). The molecular mechanism underlying amyloid-β accumulation is largely unknown, but recent evidence suggests that impaired amyloid-β clearance plays a critical role in its accumulation. The review provides an overview of recent research and proposes strategies for efficient amyloid-β clearance in both the brain and periphery. The clearance of amyloid-β can occur through enzymatic or non-enzymatic pathways in the brain, including neuronal and glial cells, blood-brain barrier, interstitial fluid bulk flow, perivascular drainage, and cerebrospinal fluid absorption-mediated pathways. In the periphery, various mechanisms, including peripheral organs, immunomodulation/immune cells, enzymes, amyloid-β-binding proteins, and amyloid-β-binding cells, are involved in amyloid-β clearance. Although recent findings have shed light on amyloid-β clearance in both regions, opportunities remain in areas where limited data is available. Therefore, future strategies that enhance amyloid-β clearance in the brain and/or periphery, either through central or peripheral clearance approaches or in combination, are highly encouraged. These strategies will provide new insight into the disease pathogenesis at the molecular level and explore new targets for inhibiting amyloid-β deposition, which is central to the pathogenesis of sporadic AD (amyloid-β in parenchyma) and CAA (amyloid-β in blood vessels).
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Affiliation(s)
- Rahat Ullah
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, School of Medicine, The Johns Hopkins University, Baltimore, MD 21205, USA
- Department of Neurology, School of Medicine, The Johns Hopkins University, Baltimore, MD 21205, USA
| | - Eun Jeong Lee
- Department of Brain Science, Ajou University School of Medicine, Suwon 16499, Korea
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Zhang L, Xia Y, Gui Y. Neuronal ApoE4 in Alzheimer's disease and potential therapeutic targets. Front Aging Neurosci 2023; 15:1199434. [PMID: 37333457 PMCID: PMC10272394 DOI: 10.3389/fnagi.2023.1199434] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Accepted: 05/16/2023] [Indexed: 06/20/2023] Open
Abstract
The most prevalent genetic risk factor for Alzheimer's disease (AD) is Apolipoprotein E (ApoE), a gene located on chromosome 19 that encodes three alleles (e2, e3, and e4) that give rise to the ApoE subtypes E2, E3, and E4, respectively. E2 and E4 have been linked to increased plasma triglyceride concentrations and are known to play a critical role in lipoprotein metabolism. The prominent pathological features of AD mainly include senile plaques formed by amyloid β (Aβ42) aggregation and neuronal fibrous tangles (NFTs), and the deposited plaques are mainly composed of Aβ hyperphosphorylation and truncated head. In the central nervous system, the ApoE protein is primarily derived from astrocytes, but ApoE is also produced when neurons are stressed or affected by certain stress, injury, and aging conditions. ApoE4 in neurons induces Aβ and tau protein pathologies, leading to neuroinflammation and neuronal damage, impairing learning and memory functions. However, how neuronal ApoE4 mediates AD pathology remains unclear. Recent studies have shown that neuronal ApoE4 may lead to greater neurotoxicity, which increases the risk of AD development. This review focuses on the pathophysiology of neuronal ApoE4 and explains how neuronal ApoE4 mediates Aβ deposition, pathological mechanisms of tau protein hyperphosphorylation, and potential therapeutic targets.
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Bader AS, Gnädig MU, Fricke M, Büschgens L, Berger LJ, Klafki HW, Meyer T, Jahn O, Weggen S, Wirths O. Brain Region-Specific Differences in Amyloid-β Plaque Composition in 5XFAD Mice. Life (Basel) 2023; 13:life13041053. [PMID: 37109582 PMCID: PMC10145597 DOI: 10.3390/life13041053] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 04/11/2023] [Accepted: 04/18/2023] [Indexed: 04/29/2023] Open
Abstract
Senile plaques consisting of amyloid-beta (Aβ) peptides are a major pathological hallmark of Alzheimer's disease (AD). Aβ peptides are heterogeneous regarding the exact length of their amino- and carboxy-termini. Aβ1-40 and Aβ1-42 are often considered to represent canonical "full-length" Aβ species. Using immunohistochemistry, we analyzed the distribution of Aβ1-x, Aβx-42 and Aβ4-x species in amyloid deposits in the subiculum, hippocampus and cortex in 5XFAD mice during aging. Overall plaque load increased in all three brain regions, with the subiculum being the area with the strongest relative plaque coverage. In the subiculum, but not in the other brain regions, the Aβ1-x load peaked at an age of five months and decreased thereafter. In contrast, the density of plaques positive for N-terminally truncated Aβ4-x species increased continuously over time. We hypothesize that ongoing plaque remodeling takes place, leading to a conversion of deposited Aβ1-x peptides into Aβ4-x peptides in brain regions with a high Aβ plaque burden.
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Affiliation(s)
- Angelika Sabine Bader
- Department of Psychiatry and Psychotherapy, University Medical Center (UMG), Georg-August-University, 37075 Göttingen, Germany
| | - Marius-Uwe Gnädig
- Department of Psychiatry and Psychotherapy, University Medical Center (UMG), Georg-August-University, 37075 Göttingen, Germany
| | - Merle Fricke
- Department of Psychiatry and Psychotherapy, University Medical Center (UMG), Georg-August-University, 37075 Göttingen, Germany
| | - Luca Büschgens
- Department of Psychiatry and Psychotherapy, University Medical Center (UMG), Georg-August-University, 37075 Göttingen, Germany
| | - Lena Josefine Berger
- Department of Psychiatry and Psychotherapy, University Medical Center (UMG), Georg-August-University, 37075 Göttingen, Germany
| | - Hans-Wolfgang Klafki
- Department of Psychiatry and Psychotherapy, University Medical Center (UMG), Georg-August-University, 37075 Göttingen, Germany
| | - Thomas Meyer
- Department of Psychosomatic Medicine and Psychotherapy, University Medical Center (UMG), Georg-August-University, 37075 Göttingen, Germany
| | - Olaf Jahn
- Department of Psychiatry and Psychotherapy, University Medical Center (UMG), Georg-August-University, 37075 Göttingen, Germany
- Neuroproteomics Group, Department of Molecular Neurobiology, Max Planck Institute for Multidisciplinary Sciences, 37075 Göttingen, Germany
| | - Sascha Weggen
- Department of Neuropathology, Heinrich-Heine-University, 40225 Düsseldorf, Germany
| | - Oliver Wirths
- Department of Psychiatry and Psychotherapy, University Medical Center (UMG), Georg-August-University, 37075 Göttingen, Germany
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Zhang H, Li X, Wang X, Xu J, Elefant F, Wang J. Cellular response to β-amyloid neurotoxicity in Alzheimer's disease and implications in new therapeutics. Animal Model Exp Med 2023; 6:3-9. [PMID: 36872303 PMCID: PMC9986234 DOI: 10.1002/ame2.12313] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 02/07/2023] [Indexed: 03/07/2023] Open
Abstract
β-Amyloid (Aβ) is a specific pathological hallmark of Alzheimer's disease (AD). Because of its neurotoxicity, AD patients exhibit multiple brain dysfunctions. Disease-modifying therapy (DMT) is the central concept in the development of AD therapeutics today, and most DMT drugs that are currently in clinical trials are anti-Aβ drugs, such as aducanumab and lecanemab. Therefore, understanding Aβ's neurotoxic mechanism is crucial for Aβ-targeted drug development. Despite its total length of only a few dozen amino acids, Aβ is incredibly diverse. In addition to the well-known Aβ1-42 , N-terminally truncated, glutaminyl cyclase (QC) catalyzed, and pyroglutamate-modified Aβ (pEAβ) is also highly amyloidogenic and far more cytotoxic. The extracellular monomeric Aβx-42 (x = 1-11) initiates the aggregation to form fibrils and plaques and causes many abnormal cellular responses through cell membrane receptors and receptor-coupled signal pathways. These signal cascades further influence many cellular metabolism-related processes, such as gene expression, cell cycle, and cell fate, and ultimately cause severe neural cell damage. However, endogenous cellular anti-Aβ defense processes always accompany the Aβ-induced microenvironment alterations. Aβ-cleaving endopeptidases, Aβ-degrading ubiquitin-proteasome system (UPS), and Aβ-engulfing glial cell immune responses are all essential self-defense mechanisms that we can leverage to develop new drugs. This review discusses some of the most recent advances in understanding Aβ-centric AD mechanisms and suggests prospects for promising anti-Aβ strategies.
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Affiliation(s)
- Haolin Zhang
- Faculty of Environment and LifeBeijing University of TechnologyBeijingChina
| | - Xianghua Li
- Faculty of Environment and LifeBeijing University of TechnologyBeijingChina
| | - Xiaoli Wang
- Faculty of Environment and LifeBeijing University of TechnologyBeijingChina
| | - Jiayu Xu
- Faculty of Environment and LifeBeijing University of TechnologyBeijingChina
| | - Felice Elefant
- Department of BiologyDrexel UniversityPhiladelphiaPennsylvaniaUSA
| | - Juan Wang
- Faculty of Environment and LifeBeijing University of TechnologyBeijingChina
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All Roads Lead to Rome: Different Molecular Players Converge to Common Toxic Pathways in Neurodegeneration. Cells 2021; 10:cells10092438. [PMID: 34572087 PMCID: PMC8468417 DOI: 10.3390/cells10092438] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 09/12/2021] [Accepted: 09/14/2021] [Indexed: 12/14/2022] Open
Abstract
Multiple neurodegenerative diseases (NDDs) such as Alzheimer’s disease (AD), Parkinson’s disease (PD), amyotrophic lateral sclerosis (ALS) and Huntington’s disease (HD) are being suggested to have common cellular and molecular pathological mechanisms, characterized mainly by protein misfolding and aggregation. These large inclusions, most likely, represent an end stage of a molecular cascade; however, the soluble misfolded proteins, which take part in earlier steps of this cascade, are the more toxic players. These pathological proteins, which characterize each specific disease, lead to the selective vulnerability of different neurons, likely resulting from a combination of different intracellular mechanisms, including mitochondrial dysfunction, ER stress, proteasome inhibition, excitotoxicity, oxidative damage, defects in nucleocytoplasmic transport, defective axonal transport and neuroinflammation. Damage within these neurons is enhanced by damage from the nonneuronal cells, via inflammatory processes that accelerate the progression of these diseases. In this review, while acknowledging the hallmark proteins which characterize the most common NDDs; we place specific focus on the common overlapping mechanisms leading to disease pathology despite these different molecular players and discuss how this convergence may occur, with the ultimate hope that therapies effective in one disease may successfully translate to another.
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Fasae KD, Abolaji AO, Faloye TR, Odunsi AY, Oyetayo BO, Enya JI, Rotimi JA, Akinyemi RO, Whitworth AJ, Aschner M. Metallobiology and therapeutic chelation of biometals (copper, zinc and iron) in Alzheimer's disease: Limitations, and current and future perspectives. J Trace Elem Med Biol 2021; 67:126779. [PMID: 34034029 DOI: 10.1016/j.jtemb.2021.126779] [Citation(s) in RCA: 65] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2020] [Revised: 04/03/2021] [Accepted: 05/10/2021] [Indexed: 02/08/2023]
Abstract
BACKGROUND Alzheimer's disease (AD) is the most prevalent cause of cognitive impairment and dementia worldwide. The pathobiology of the disease has been studied in the form of several hypotheses, ranging from oxidative stress, amyloid-beta (Aβ) aggregation, accumulation of tau forming neurofibrillary tangles (NFT) through metal dysregulation and homeostasis, dysfunction of the cholinergic system, and to inflammatory and autophagic mechanism. However, none of these hypotheses has led to confirmed diagnostics or approved cure for the disease. OBJECTIVE This review is aimed as a basic and an encyclopedic short course into metals in AD and discusses the advances in chelation strategies and developments adopted in the treatment of the disease. Since there is accumulating evidence of the role of both biometal dyshomeostasis (iron (Fe), copper (Cu), and zinc (Zn)) and metal-amyloid interactions that lead to the pathogenesis of AD, this review focuses on unraveling therapeutic chelation strategies that have been considered in the treatment of the disease, aiming to sequester free and protein-bound metal ions and reducing cerebral metal burden. Promising compounds possessing chemically modified moieties evolving as multi-target ligands used as anti-AD drug candidates are also covered. RESULTS AND CONCLUSION Several multidirectional and multifaceted studies on metal chelation therapeutics show the need for improved synthesis, screening, and analysis of compounds to be able to effectively present chelating anti-AD drugs. Most drug candidates studied have limitations in their physicochemical properties; some enhance redistribution of metal ions, while others indirectly activate signaling pathways in AD. The metal chelation process in vivo still needs to be established and the design of potential anti-AD compounds that bi-functionally sequester metal ions as well as inhibit the Aβ aggregation by competing with the metal ions and reducing metal-induced oxidative damage and neurotoxicity may signal a bright end in chelation-based therapeutics of AD.
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Affiliation(s)
- Kehinde D Fasae
- Department of Biochemistry, Molecular Drug Metabolism and Toxicology Unit, College of Medicine, University of Ibadan, Nigeria
| | - Amos O Abolaji
- Department of Biochemistry, Molecular Drug Metabolism and Toxicology Unit, College of Medicine, University of Ibadan, Nigeria.
| | - Tolulope R Faloye
- Department of Biochemistry, Molecular Drug Metabolism and Toxicology Unit, College of Medicine, University of Ibadan, Nigeria
| | - Atinuke Y Odunsi
- Department of Biochemistry, Molecular Drug Metabolism and Toxicology Unit, College of Medicine, University of Ibadan, Nigeria
| | - Bolaji O Oyetayo
- Department of Pharmacology and Therapeutics, Neuropharmacology Unit, College of Medicine, University of Ibadan, Nigeria
| | - Joseph I Enya
- Department of Anatomy, University of Ilorin, Kwara State, Nigeria
| | - Joshua A Rotimi
- Department of Biochemistry and Molecular Biology, Obafemi Awolowo University, Ile-Ife, Nigeria
| | - Rufus O Akinyemi
- Neuroscience and Ageing Research Unit, Institute for Advanced Medical Research and Training, College of Medicine, University of Ibadan, Ibadan, Oyo State, Nigeria
| | | | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, USA.
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9
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Qi J, Yao L. Modulators of neurolysin: promising agents for the treatment of tumor and neurological diseases. Med Chem Res 2021. [DOI: 10.1007/s00044-021-02761-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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10
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Abstract
Protein aggregation and amyloid formation are pathogenic events underlying the development of an increasingly large number of human diseases named “proteinopathies”. Abnormal accumulation in affected tissues of amyloid β (Aβ) peptide, islet amyloid polypeptide (IAPP), and the prion protein, to mention a few, are involved in the occurrence of Alzheimer’s (AD), type 2 diabetes mellitus (T2DM) and prion diseases, respectively. Many reports suggest that the toxic properties of amyloid aggregates are correlated with their ability to damage cell membranes. However, the molecular mechanisms causing toxic amyloid/membrane interactions are still far to be completely elucidated. This review aims at describing the mutual relationships linking abnormal protein conformational transition and self-assembly into amyloid aggregates with membrane damage. A cross-correlated analysis of all these closely intertwined factors is thought to provide valuable insights for a comprehensive molecular description of amyloid diseases and, in turn, the design of effective therapies.
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11
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García-Viñuales S, Sciacca MFM, Lanza V, Santoro AM, Grasso G, Tundo GR, Sbardella D, Coletta M, Grasso G, La Rosa C, Milardi D. The interplay between lipid and Aβ amyloid homeostasis in Alzheimer's Disease: risk factors and therapeutic opportunities. Chem Phys Lipids 2021; 236:105072. [PMID: 33675779 DOI: 10.1016/j.chemphyslip.2021.105072] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 02/15/2021] [Accepted: 03/01/2021] [Indexed: 12/19/2022]
Abstract
Alzheimer's Diseases (AD) is characterized by the accumulation of amyloid deposits of Aβ peptide in the brain. Besides genetic background, the presence of other diseases and an unhealthy lifestyle are known risk factors for AD development. Albeit accumulating clinical evidence suggests that an impaired lipid metabolism is related to Aβ deposition, mechanistic insights on the link between amyloid fibril formation/clearance and aberrant lipid interactions are still unavailable. Recently, many studies have described the key role played by membrane bound Aβ assemblies in neurotoxicity. Moreover, it has been suggested that a derangement of the ubiquitin proteasome pathway and autophagy is significantly correlated with toxic Aβ aggregation and dysregulation of lipid levels. Thus, studies focusing on the role played by lipids in Aβ aggregation and proteostasis could represent a promising area of investigation for the design of valuable treatments. In this review we examine current knowledge concerning the effects of lipids in Aβ aggregation and degradation processes, focusing on the therapeutic opportunities that a comprehensive understanding of all biophysical, biochemical, and biological processes involved may disclose.
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Affiliation(s)
| | - Michele F M Sciacca
- Consiglio Nazionale delle Ricerche, Istituto di Cristallografia, Catania, Italy
| | - Valeria Lanza
- Consiglio Nazionale delle Ricerche, Istituto di Cristallografia, Catania, Italy
| | - Anna Maria Santoro
- Consiglio Nazionale delle Ricerche, Istituto di Cristallografia, Catania, Italy
| | - Giulia Grasso
- Consiglio Nazionale delle Ricerche, Istituto di Cristallografia, Catania, Italy
| | - Grazia R Tundo
- Department of Clinical Sciences and Translational Medicine, University of Rome Tor Vergata, Rome, Italy
| | | | - Massimiliano Coletta
- Department of Clinical Sciences and Translational Medicine, University of Rome Tor Vergata, Rome, Italy
| | - Giuseppe Grasso
- Department of Chemistry, University of Catania, Catania, Italy
| | - Carmelo La Rosa
- Department of Chemistry, University of Catania, Catania, Italy
| | - Danilo Milardi
- Consiglio Nazionale delle Ricerche, Istituto di Cristallografia, Catania, Italy.
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Zhang H, Karisetty BC, Bhatnagar A, Armour EM, Beaver M, Roach TV, Mortazavi S, Mandloi S, Elefant F. Tip60 protects against amyloid-β-induced transcriptomic alterations via different modes of action in early versus late stages of neurodegeneration. Mol Cell Neurosci 2020; 109:103570. [PMID: 33160016 DOI: 10.1016/j.mcn.2020.103570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2020] [Revised: 10/24/2020] [Accepted: 10/31/2020] [Indexed: 10/23/2022] Open
Abstract
Alzheimer's disease (AD) is an age-related neurodegenerative disorder hallmarked by amyloid-β (Aβ) plaque accumulation, neuronal cell death, and cognitive deficits that worsen during disease progression. Histone acetylation dysregulation, caused by an imbalance between reduced histone acetyltransferases (HAT) Tip60 and increased histone deacetylase 2 (HDAC2) levels, can directly contribute to AD pathology. However, whether such AD-associated neuroepigenetic alterations occur in response to Aβ peptide production and can be protected against by increasing Tip60 levels over the course of neurodegenerative progression remains unknown. Here we profile Tip60 HAT/HDAC2 dynamics and transcriptome-wide changes across early and late stage AD pathology in the Drosophila brain produced solely by human amyloid-β42. We show that early Aβ42 induction leads to disruption of Tip60 HAT/HDAC2 balance during early neurodegenerative stages preceding Aβ plaque accumulation that persists into late AD stages. Correlative transcriptome-wide studies reveal alterations in biological processes we classified as transient (early-stage only), late-onset (late-stage only), and constant (both). Increasing Tip60 HAT levels in the Aβ42 fly brain protects against AD functional pathologies that include Aβ plaque accumulation, neural cell death, cognitive deficits, and shorter life-span. Strikingly, Tip60 protects against Aβ42-induced transcriptomic alterations via distinct mechanisms during early and late stages of neurodegeneration. Our findings reveal distinct modes of neuroepigenetic gene changes and Tip60 neuroprotection in early versus late stages in AD that can serve as early biomarkers for AD, and support the therapeutic potential of Tip60 over the course of AD progression.
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Affiliation(s)
- Haolin Zhang
- Department of Biology, Drexel University, Philadelphia, PA, United States
| | | | - Akanksha Bhatnagar
- Department of Biology, Drexel University, Philadelphia, PA, United States
| | - Ellen M Armour
- Department of Biology, Drexel University, Philadelphia, PA, United States
| | - Mariah Beaver
- Department of Biology, Drexel University, Philadelphia, PA, United States
| | - Tiffany V Roach
- Department of Biology, Drexel University, Philadelphia, PA, United States
| | - Sina Mortazavi
- Department of Biology, Drexel University, Philadelphia, PA, United States
| | - Shreya Mandloi
- Department of Biology, Drexel University, Philadelphia, PA, United States
| | - Felice Elefant
- Department of Biology, Drexel University, Philadelphia, PA, United States.
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13
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Zhang L, Wu Y, Yang G, Gan H, Sang D, Zhou J, Su L, Wang R, Ma L. Design, synthesis and biological evaluation of novel osthole-based derivatives as potential neuroprotective agents. Bioorg Med Chem Lett 2020; 30:127633. [PMID: 33132198 DOI: 10.1016/j.bmcl.2020.127633] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 10/13/2020] [Accepted: 10/16/2020] [Indexed: 01/19/2023]
Abstract
A total of 26 compounds based on osthole skeleton were designed, synthesized. Their cytoprotective abilities of antioxidation, anti-inflammation and Aβ42(Amyloid β-protein 42)-induced neurotoxicity were evaluated by MTT assays. Mechanism of the action of selected compounds were investigated by molecular docking. AlogP, logS and blood-brain barrier (BBB) permeability of all these compounds were simulated by admetSAR. Most of the compounds showed better antioxidative and anti-inflammatory activities compared with osthole, especially OST7 and OST17. The compound OST7 showed relative high activity in neuroprotection against H2O2 (45.7 ± 5.5%), oxygen glucose deprivation (64.6 ± 4.8%) and Aβ42 (61.4 ± 5.2%) at a low concentration of 10 μM. EC50 of selected compounds were measured in both H2O2 and OGD induced cytotoxicity models. Moreover, NO inhibiting ability of OST17(50.4 ± 7.1%) already surpassed the positive drug indomethacin. The structure activity relationship study indicated that introduction of piperazine group, tetrahydropyrrole group and aromatic amine group might be beneficial for enhancement of osthole neuroprotective properties. Molecular docking explained that the reason OST7 exhibited relatively stronger neuroprotection against Aβ because of the greater area of interactions between molecule and target protein. OST7 and OST17 both provided novel methods to investigate osthole as anti-AD drugs.
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Affiliation(s)
- Li Zhang
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Yuhang Wu
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Guixiang Yang
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Haixian Gan
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Dayong Sang
- College of Chemical Engineering and Pharmacy, Jingchu University of Technology, Jingmen, Hubei 448000, China
| | - Jiye Zhou
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Lin Su
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Rui Wang
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China.
| | - Lei Ma
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China.
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14
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Lu TT, Wan C, Yang W, Cai Z. Role of Cdk5 in Amyloid-beta Pathology of Alzheimer’s Disease. Curr Alzheimer Res 2020; 16:1206-1215. [PMID: 31820699 DOI: 10.2174/1567205016666191210094435] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 11/29/2019] [Accepted: 12/09/2019] [Indexed: 12/14/2022]
Abstract
Alzheimer’s Disease (AD) is a progressive neurodegenerative disease with irreversible cognitive
impairment. So far, successful treatment and prevention for this disease are deficient in spite of delaying
the progression of cognitive impairment and dementia. Cyclin dependent kinase 5 (Cdk5), a
unique member of the cyclin-dependent kinase family, is involved in AD pathogenesis and may be a
pathophysiological mediator that links the major pathological features of AD. Cdk5 dysregulation interferes
with the proteolytic processing of Amyloid-beta Protein Precursor (APP) and modulates amyloidbeta
(Aβ) by affecting three enzymes called α-, β- and γ-secretase, which are critical for the hydrolysis
of APP. Given that the accumulation and deposition of Aβ derived from APP are a common hinge point
in the numerous pathogenic hypotheses of AD, figuring out that influence of specific mechanisms of
Cdk5 on Aβ pathology will deepen our understanding of AD.
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Affiliation(s)
- Tao-Tao Lu
- Department of Neurology, Chongqing General Hospital, University of Chinese Academy of Sciences, 400013, Chongqing, China
| | - Chengqun Wan
- Department of Neurology, Chongqing General Hospital, University of Chinese Academy of Sciences, 400013, Chongqing, China
| | - Wenming Yang
- Departmentof Neurology, The First Affiliated Hospital of Anhui University of Chinese Medicine, Hefei, 230031 Anhui Province, China
| | - Zhiyou Cai
- Department of Neurology, Chongqing General Hospital, University of Chinese Academy of Sciences, 400013, Chongqing, China
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Hickman SE, Allison EK, Coleman U, Kingery-Gallagher ND, El Khoury J. Heterozygous CX3CR1 Deficiency in Microglia Restores Neuronal β-Amyloid Clearance Pathways and Slows Progression of Alzheimer's Like-Disease in PS1-APP Mice. Front Immunol 2019; 10:2780. [PMID: 31849963 PMCID: PMC6900980 DOI: 10.3389/fimmu.2019.02780] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2019] [Accepted: 11/13/2019] [Indexed: 02/03/2023] Open
Abstract
CX3CR1 is a chemokine receptor expressed on microglia that binds Fractalkine (CX3CL1) and regulates microglial recruitment to sites of neuroinflammation. Full deletion of CX3CR1 in mouse models of Alzheimer's disease have opposing effects on amyloid-β and tau pathologies raising concerns about the benefits of targeting CX3CR1 for treatment of this disease. Since most therapies achieve only partial blockade of their targets, we investigated the effects of partial CX3CR1 deficiency on the development and progression of amyloid-β deposition in the PS1-APP Alzheimer's mouse model. We generated PS1-APP mice heterozygous for CX3CR1 (PS1-APP-CX3CR1+/−) and analyzed these mice for Alzheimer's-like pathology. We found that partial CX3CR1 deficiency was associated with a significant reduction in Aβ levels and in senile-like plaque load in the brain as compared with age-matched PS1-APP mice. Reduced Aβ level in the brain was associated with improved cognitive function. Levels of the neuronal-expressed Aβ-degrading enzymes insulysin and matrix metalloproteinase 9, which are reduced in the brains of regular PS1-APP mice, were significantly higher in PS1-APP-CX3CR1+/− mice. Our data indicate that lowering CX3CR1 levels or partially inhibiting its activity in the brain may be a therapeutic strategy to increase neuronal Aβ clearance, reduce Aβ levels and delay progression of Alzheimer's-Like disease. Our findings also suggest a novel pathway where microglial CX3CR1 can regulates gene expression in neurons.
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Affiliation(s)
- Suzanne E Hickman
- Center for Immunology and Inflammatory Diseases, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, United States
| | - Elizabeth K Allison
- Center for Immunology and Inflammatory Diseases, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, United States
| | - Uwanda Coleman
- Center for Immunology and Inflammatory Diseases, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, United States
| | - Nathan D Kingery-Gallagher
- Center for Immunology and Inflammatory Diseases, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, United States
| | - Joseph El Khoury
- Center for Immunology and Inflammatory Diseases, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, United States.,Division of Infectious Diseases, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, United States
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Du J, Li S, Su Y, Wang H, Liu H, Cui H. The role of extracellular matrix metalloproteinase inducer on the action of dihydrotestosterone against the cellular damage induced by Aβ 42. Mol Cell Endocrinol 2019; 498:110536. [PMID: 31401349 DOI: 10.1016/j.mce.2019.110536] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2019] [Revised: 08/07/2019] [Accepted: 08/08/2019] [Indexed: 11/24/2022]
Abstract
Clinical studies have revealed that the risk of Alzheimer's disease (AD) in men is increased by age-related androgen depletion. The level of β-amyloid (Aβ) is elevated in the brains of AD patients, and Aβ is believed to play a critical role in the pathology of AD. Some studies have indicated that androgens affect AD risk by regulating the metabolism of Aβ by an unclear mechanism. In this study, we investigated the role of the extracellular matrix metalloproteinase inducer (CD147) in this action. Initially, we demonstrated that androgens positively regulate the expression of CD147 in adult male rats and SH-SY5Y cells. Furthermore, this regulation may involve androgen receptor (AR). Additionally, interference of CD147 expression decreased the clearance of Aβ in culture medium and reduced cell viability. It also affected the morphology of the cells and the expression of apoptosis-related proteins. Finally, we found that interference of CD147 expression blocked the dihydrotestosterone (DHT)-induced reduction in Aβ and the protection of cells. DHT regulates MMP-2's expression through CD147. Together, these results imply that androgen regulation of Aβ and cell protection may be affected by interfering with the expression of CD147.
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Affiliation(s)
- Juan Du
- Department of Anatomy, Hebei Medical University, Shijiazhuang, China; Neuroscience Research Center, Hebei Medical University, Shijiazhuang, China; Human Brain Bank, Hebei Medical University, Shijiazhuang, China
| | - Sha Li
- Department of Anatomy, Hebei Medical University, Shijiazhuang, China; Neuroscience Research Center, Hebei Medical University, Shijiazhuang, China; Human Brain Bank, Hebei Medical University, Shijiazhuang, China
| | - Yuhong Su
- Department of Anatomy, Hebei Medical University, Shijiazhuang, China; Neuroscience Research Center, Hebei Medical University, Shijiazhuang, China
| | - Haidong Wang
- Department of Anatomy, Hebei Medical University, Shijiazhuang, China
| | - Hanjie Liu
- Department of Anatomy, Hebei Medical University, Shijiazhuang, China; The Second Hospital of Hebei Medical University, Shijiazhuang, China
| | - Huixian Cui
- Department of Anatomy, Hebei Medical University, Shijiazhuang, China; Neuroscience Research Center, Hebei Medical University, Shijiazhuang, China; Human Brain Bank, Hebei Medical University, Shijiazhuang, China.
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17
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Leroux F, Bosc D, Beghyn T, Hermant P, Warenghem S, Landry V, Pottiez V, Guillaume V, Charton J, Herledan A, Urata S, Liang W, Sheng L, Tang WJ, Deprez B, Deprez-Poulain R. Identification of ebselen as a potent inhibitor of insulin degrading enzyme by a drug repurposing screening. Eur J Med Chem 2019; 179:557-566. [PMID: 31276900 DOI: 10.1016/j.ejmech.2019.06.057] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 06/18/2019] [Accepted: 06/19/2019] [Indexed: 12/15/2022]
Abstract
Insulin-degrading enzyme, IDE, is a metalloprotease implicated in the metabolism of key peptides such as insulin, glucagon, β-amyloid peptide. Recent studies have pointed out its broader role in the cell physiology. In order to identify new drug-like inhibitors of IDE with optimal pharmacokinetic properties to probe its multiple roles, we ran a high-throughput drug repurposing screening. Ebselen, cefmetazole and rabeprazole were identified as reversible inhibitors of IDE. Ebselen is the most potent inhibitor (IC50(insulin) = 14 nM). The molecular mode of action of ebselen was investigated by biophysical methods. We show that ebselen induces the disorder of the IDE catalytic cleft, which significantly differs from the previously reported IDE inhibitors. IDE inhibition by ebselen can explain some of its reported activities in metabolism as well as in neuroprotection.
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Affiliation(s)
- Florence Leroux
- Univ. Lille, Inserm, Institut Pasteur de Lille, U1177, Drugs and Molecules for Living Systems, F-59000, Lille, France
| | - Damien Bosc
- Univ. Lille, Inserm, Institut Pasteur de Lille, U1177, Drugs and Molecules for Living Systems, F-59000, Lille, France
| | | | - Paul Hermant
- Univ. Lille, Inserm, Institut Pasteur de Lille, U1177, Drugs and Molecules for Living Systems, F-59000, Lille, France
| | - Sandrine Warenghem
- Univ. Lille, Inserm, Institut Pasteur de Lille, U1177, Drugs and Molecules for Living Systems, F-59000, Lille, France
| | - Valérie Landry
- Univ. Lille, Inserm, Institut Pasteur de Lille, U1177, Drugs and Molecules for Living Systems, F-59000, Lille, France
| | - Virginie Pottiez
- Univ. Lille, Inserm, Institut Pasteur de Lille, U1177, Drugs and Molecules for Living Systems, F-59000, Lille, France
| | - Valentin Guillaume
- Univ. Lille, Inserm, Institut Pasteur de Lille, U1177, Drugs and Molecules for Living Systems, F-59000, Lille, France
| | - Julie Charton
- Univ. Lille, Inserm, Institut Pasteur de Lille, U1177, Drugs and Molecules for Living Systems, F-59000, Lille, France; European Genomic Institute for Diabetes, EGID, University of Lille, F-59000, France
| | - Adrien Herledan
- Univ. Lille, Inserm, Institut Pasteur de Lille, U1177, Drugs and Molecules for Living Systems, F-59000, Lille, France
| | - Sarah Urata
- Department of Medicine, University of California at San Diego, CA 92093, La Jolla, United States
| | - Wenguang Liang
- Ben-May Institute for Cancer Research, The University of Chicago, IL 60637, Chicago, United States
| | - Li Sheng
- Department of Medicine, University of California at San Diego, CA 92093, La Jolla, United States
| | - Wei-Jen Tang
- Ben-May Institute for Cancer Research, The University of Chicago, IL 60637, Chicago, United States
| | - Benoit Deprez
- Univ. Lille, Inserm, Institut Pasteur de Lille, U1177, Drugs and Molecules for Living Systems, F-59000, Lille, France; APTEEUS, F-59000, Lille, France; European Genomic Institute for Diabetes, EGID, University of Lille, F-59000, France
| | - Rebecca Deprez-Poulain
- Univ. Lille, Inserm, Institut Pasteur de Lille, U1177, Drugs and Molecules for Living Systems, F-59000, Lille, France; European Genomic Institute for Diabetes, EGID, University of Lille, F-59000, France; Institut Universitaire de France, F- 75231, Paris, France.
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18
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Maarouf CL, Walker JE, Sue LI, Dugger BN, Beach TG, Serrano GE. Impaired hepatic amyloid-beta degradation in Alzheimer's disease. PLoS One 2018; 13:e0203659. [PMID: 30192871 PMCID: PMC6128628 DOI: 10.1371/journal.pone.0203659] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 08/26/2018] [Indexed: 12/26/2022] Open
Abstract
Extensive research strongly suggests that amyloid beta (Aβ) aggregates in the brain have a central role in Alzheimer's disease (AD) pathogenesis. Pathological Aβ deposition is likely due to an altered balance between overproduction and elimination. Rodent studies have suggested that the liver has a major role in Aβ degradation. It is possible alterations of liver function could affect brain Aβ levels through changes in blood Aβ concentration. In this study, we hypothesized hepatic Aβ degradation to be impaired in AD subjects. To test our hypothesis, an Aβ degradation assay was developed using synthetic fluorescein-labeled Aβ40 and Aβ42 spiked into human liver homogenates. Aβ degradation rates were lower in AD-derived homogenates as compared with those from non-demented (ND) control subjects, even after accounting for such covariates as age, sex, and APOE genotype. The protein expression of potential Aβ-degrading enzymes were also examined. Neprilysin levels were not different in AD liver samples, while cathepsin D and insulin-degrading enzyme were significantly altered in AD subjects. The results support the possibility that impaired hepatic Aβ degradation could be a factor contributing to increased brain Aβ accumulation and AD.
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Affiliation(s)
- Chera L. Maarouf
- Banner Sun Health Research Institute, Sun City, AZ, United States of America
| | - Jessica E. Walker
- Banner Sun Health Research Institute, Sun City, AZ, United States of America
| | - Lucia I. Sue
- Banner Sun Health Research Institute, Sun City, AZ, United States of America
| | - Brittany N. Dugger
- Department of Pathology and Laboratory Medicine, University of California Davis School of Medicine, Sacramento, CA, United States of America
| | - Thomas G. Beach
- Banner Sun Health Research Institute, Sun City, AZ, United States of America
| | - Geidy E. Serrano
- Banner Sun Health Research Institute, Sun City, AZ, United States of America
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Insulin-signaling Pathway Regulates the Degradation of Amyloid β-protein via Astrocytes. Neuroscience 2018; 385:227-236. [PMID: 29932983 DOI: 10.1016/j.neuroscience.2018.06.018] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2018] [Revised: 06/09/2018] [Accepted: 06/11/2018] [Indexed: 01/06/2023]
Abstract
Alzheimer's disease (AD) has been considered as a metabolic dysfunction disease associated with impaired insulin signaling. Determining the mechanisms underlying insulin signaling dysfunction and resistance in AD will be important for its treatment. Impaired clearance of amyloid-β peptide (Aβ) significantly contributes to amyloid accumulation, which is typically observed in the brain of AD patients. Reduced expression of important Aβ-degrading enzymes in the brain, such as neprilysin (NEP) and insulin-degrading enzyme (IDE), can promote Aβ deposition in sporadic late-onset AD patients. Here, we investigated whether insulin regulates the degradation of Aβ by inducing expression of NEP and IDE in cultured astrocytes. Treatment of astrocytes with insulin significantly reduced cellular NEP levels, but increased IDE expression. The effects of insulin on the expression of NEP and IDE involved activation of an extracellular signal-regulated kinase (ERK)-mediated pathway. The reduction in cellular NEP levels was associated with NEP secretion into the culture medium, whereas IDE was increased in the cell membranes. Moreover, insulin-treated astrocytes significantly facilitated the degradation of exogenous Aβ within the culture medium. Interestingly, pretreatment of astrocytes with an ERK inhibitor prior to insulin exposure markedly inhibited insulin-induced degradation of Aβ. These results suggest that insulin exposure enhanced Aβ degradation via an increase in NEP secretion and IDE expression in astrocytes, via activation of the ERK-mediated pathway. The inhibition of insulin signaling pathways delayed Aβ degradation by attenuating alterations in NEP and IDE levels and competition with insulin and Aβ. Our results provide further insight into the pathological relevance of insulin resistance in AD development.
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Zhao N, Liu CC, Qiao W, Bu G. Apolipoprotein E, Receptors, and Modulation of Alzheimer's Disease. Biol Psychiatry 2018; 83:347-357. [PMID: 28434655 PMCID: PMC5599322 DOI: 10.1016/j.biopsych.2017.03.003] [Citation(s) in RCA: 230] [Impact Index Per Article: 38.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 03/07/2017] [Accepted: 03/08/2017] [Indexed: 12/31/2022]
Abstract
Apolipoprotein E (apoE) is a lipid carrier in both the peripheral and the central nervous systems. Lipid-loaded apoE lipoprotein particles bind to several cell surface receptors to support membrane homeostasis and injury repair in the brain. Considering prevalence and relative risk magnitude, the ε4 allele of the APOE gene is the strongest genetic risk factor for late-onset Alzheimer's disease (AD). ApoE4 contributes to AD pathogenesis by modulating multiple pathways, including but not limited to the metabolism, aggregation, and toxicity of amyloid-β peptide, tauopathy, synaptic plasticity, lipid transport, glucose metabolism, mitochondrial function, vascular integrity, and neuroinflammation. Emerging knowledge on apoE-related pathways in the pathophysiology of AD presents new opportunities for AD therapy. We describe the biochemical and biological features of apoE and apoE receptors in the central nervous system. We also discuss the evidence and mechanisms addressing differential effects of apoE isoforms and the role of apoE receptors in AD pathogenesis, with a particular emphasis on the clinical and preclinical studies related to amyloid-β pathology. Finally, we summarize the current strategies of AD therapy targeting apoE, and postulate that effective strategies require an apoE isoform-specific approach.
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Affiliation(s)
- Na Zhao
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Chia-Chen Liu
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Wenhui Qiao
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Guojun Bu
- Department of Neuroscience, Mayo Clinic, Jacksonville, Florida; Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, College of Medicine, Xiamen University, Xiamen, Fujian, China.
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21
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Transcriptional Effects of ApoE4: Relevance to Alzheimer's Disease. Mol Neurobiol 2017; 55:5243-5254. [PMID: 28879423 DOI: 10.1007/s12035-017-0757-2] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Accepted: 08/24/2017] [Indexed: 10/18/2022]
Abstract
The major genetic risk factor for sporadic Alzheimer's disease (AD) is the lipid binding and transporting carrier protein apolipoprotein E, epsilon 4 allele (ApoE4). One of the unsolved mysteries of AD is how the presence of ApoE4 elicits this age-associated, currently incurable neurodegenerative disease. Recently, we showed that ApoE4 acts as a transcription factor and binds to the promoters of genes involved in a range of processes linked to aging and AD disease pathogenesis. These findings point to novel therapeutic strategies for AD and aging, resulting in an extension of human healthspan, the disease-free and functional period of life. Here, we review the effects and implications of the putative transcriptional role of ApoE4 and propose a model of Alzheimer's disease that focuses on the transcriptional nature of ApoE4 and its downstream effects, with the aim that this knowledge will help to define the role ApoE4 plays as a risk factor for AD, aging, and other processes such as inflammation and cardiovascular disease.
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Pardeshi R, Bolshette N, Gadhave K, Ahire A, Ahmed S, Cassano T, Gupta VB, Lahkar M. Insulin signaling: An opportunistic target to minify the risk of Alzheimer's disease. Psychoneuroendocrinology 2017. [PMID: 28624654 DOI: 10.1016/j.psyneuen.2017.05.004] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Alzheimer's disease (AD) is progressive neurodegenerative disorder characterized by accumulation of senile plaques, neurofibrillary tangles (NFT) and neurodegeneration. The diabetes mellitus (DM) is one of the risk factors for AD pathogenesis by impairment in insulin signaling and glucose metabolism in central as well as peripheral system. Insulin resistance, impaired glucose and lipid metabolism are leading to the Aβ (Aβ) aggregation, Tau phosphorylation, mitochondrial dysfunction, oxidative stress, protein misfolding, memory impairment and also mark over Aβ transport through central to peripheral and vice versa. Several pathways, like enzymatic degradation of Aβ, forkhead box protein O1 (FOXO) signaling, insulin signaling shared common pathological mechanism for both AD and DM. Recent evidence showed that hyperinsulinemia and hyperglycemia affect the onset and progression of AD differently. Some researchers have suggested that hyperglycemia influences vascular tone, while hyperinsulinemia may underlie mitochondrial deficit. The objective of this review is to determine whether existing evidence supports the concept that impairment in insulin signaling and glucose metabolism play an important role in pathogenesis of AD. In the first part of this review, we tried to explain the interconnecting link between AD and DM, whereas the second part includes more information on insulin resistance and its involvement in AD pathogenesis. In the final part of this review, we have focused more toward the AD treatment by targeting insulin signaling like anti-diabetic, antioxidant, nutraceuticals and dietary supplements. To date, more researches should be done in this field in order to explore the pathways in insulin signaling, which might ameliorate the treatment options and reduce the risk of AD due to DM.
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Affiliation(s)
- Rohit Pardeshi
- Department of Biotechnology, National Institute of Pharmaceutical Education and Research (NIPER), Gauhati Medical College, Guwahati 781032, Assam, India
| | - Nityanand Bolshette
- Institutional Level Biotech hub (IBT hub), Department of Biotechnology, National Institute of Pharmaceutical Education and Research (NIPER), Gauhati Medical College, Guwahati 781032, Assam, India
| | - Kundlik Gadhave
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Gauhati Medical College, Guwahati 781032, Assam, India
| | - Ashutosh Ahire
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Gauhati Medical College, Guwahati 781032, Assam, India
| | - Sahabuddin Ahmed
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Gauhati Medical College, Guwahati 781032, Assam, India
| | - Tommaso Cassano
- Department of Clinical and Experimental Medicine, University of Foggia, Via Luigi Pinto, c/o Ospedali Riuniti, 71122 Foggia, Italy
| | - Veer Bala Gupta
- Centre of Excellence for Alzheimer's Disease Research & Care, School of Medical Sciences, Edith-Cowan University, Joondalup, WA 6027, Australia
| | - Mangala Lahkar
- Department of Biotechnology, National Institute of Pharmaceutical Education and Research (NIPER), Gauhati Medical College, Guwahati 781032, Assam, India; Institutional Level Biotech hub (IBT hub), Department of Biotechnology, National Institute of Pharmaceutical Education and Research (NIPER), Gauhati Medical College, Guwahati 781032, Assam, India; Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Gauhati Medical College, Guwahati 781032, Assam, India.
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23
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Amyloid-β Derived from the Brain of the Alzheimer’s Disease Transgenic Mouse Is Resistant to Proteolytic Digestion Due to Its Conformation. J Mol Neurosci 2017; 62:412-419. [DOI: 10.1007/s12031-017-0949-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Accepted: 07/12/2017] [Indexed: 10/19/2022]
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24
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Huang C, Dong D, Jiao Q, Pan H, Ma L, Wang R. Sarsasapogenin-AA13 ameliorates Aβ-induced cognitive deficits via improving neuroglial capacity on Aβ clearance and antiinflammation. CNS Neurosci Ther 2017; 23:498-509. [PMID: 28466999 DOI: 10.1111/cns.12697] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Revised: 03/11/2017] [Accepted: 03/17/2017] [Indexed: 01/14/2023] Open
Abstract
AIMS Sarsasapogenin has been reported to improve dementia symptoms somehow, probably through modulating the function of cholinergic system, suppressing neurofibrillary tangles, and inhibiting inflammation. However, the role of sarsasapogenin in response to beta-amyloid (Aβ) remains to be delineated. This study aimed to determine the therapeutic effect of sarsasapogenin-13 (AA13, a sarsasapogenin derivative) on learning and memory impairments in Aβ-injected mice, as well as the role of AA13 in neuroglia-mediated antiinflammation and Aβ clearance. METHODS Focusing on the role of AA13 in regulating glial responses to Aβ, we conducted behavioral, morphological, and protein expression studies to explore the effects of AA13 on Aβ clearance and inflammatory regulation. RESULTS The results indicated that oral administration of AA13 attenuated the memory deficits of intracerebroventricular (i.c.v.) Aβ-injected mice; also, AA13 protected neuroglial cells against Aβ-induced cytotoxicity. The further mechanical studies demonstrated that AA13 reversed the upregulation of proinflammatory M1 markers and increased the expression of antiinflammatory M2 markers in Aβ-treated cells. Furthermore, AA13 facilitated Aβ clearance through promoting Aβ phagocytosis and degradation. AA13 modulated the expression of fatty acid translocase (CD36), insulin-degrading enzyme (IDE), neprilysin (NEP), and endothelin-converting enzyme (ECE) in neuroglia. CONCLUSION The present study indicated that the neuroprotective effect of AA13 might relate to its modulatory effects on microglia activation state, phagocytic ability, and expression of Aβ-degrading enzymes, which makes it a promising therapeutic agent in the early stage of Alzheimer's disease (AD).
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Affiliation(s)
- Cui Huang
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, China
| | - Dong Dong
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, China
| | - Qian Jiao
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, China
| | - Hui Pan
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, China
| | - Lei Ma
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, China
| | - Rui Wang
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, China
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25
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The effect of angiotensin receptor neprilysin inhibitor, sacubitril/valsartan, on central nervous system amyloid-β concentrations and clearance in the cynomolgus monkey. Toxicol Appl Pharmacol 2017; 323:53-65. [DOI: 10.1016/j.taap.2017.03.014] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Revised: 03/13/2017] [Accepted: 03/14/2017] [Indexed: 01/11/2023]
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26
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Zhao J, Ma B, Nussinov R. Compilation and Analysis of Enzymes, Engineered Antibodies, and Nanoparticles Designed to Interfere with Amyloid-β Aggregation. Isr J Chem 2016. [DOI: 10.1002/ijch.201600093] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Jun Zhao
- Cancer and Inflammation Program; National Cancer Institute; Frederick Maryland 21702 USA
| | - Buyong Ma
- Basic Science Program; Leidos Biomedical Research, Inc.; Cancer and Inflammation Program; National Cancer Institute; Frederick Maryland 21702 USA
| | - Ruth Nussinov
- Basic Science Program; Leidos Biomedical Research, Inc.; Cancer and Inflammation Program; National Cancer Institute; Frederick Maryland 21702 USA
- Sackler Institute of Molecular Medicine; Department of Human Genetics and Molecular Medicine; Sackler School of Medicine; Tel Aviv University; Tel Aviv 69978 Israel
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27
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Liu RX, Huang C, Bennett DA, Li H, Wang R. The characteristics of astrocyte on Aβ clearance altered in Alzheimer's disease were reversed by anti-inflammatory agent (+)-2-(1-hydroxyl-4-oxocyclohexyl) ethyl caffeate. Am J Transl Res 2016; 8:4082-4094. [PMID: 27829994 PMCID: PMC5095303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2016] [Accepted: 08/09/2016] [Indexed: 06/06/2023]
Abstract
Astrocytes are closely related to the amyloid-β (Aβ) deposition in the brain and play crucial roles in Alzheimer's disease (AD) pathology. Meanwhile, inflammation in the CNS has been increasingly demonstrated as a prominent hallmark in AD. Our data from animal models and subjects with Alzheimer's disease (AD) showed GFAP immunoreactivity altered in different stage of AD and had a positive correlation with neprilysin (NEP), suggesting astrocytes might take a protective role in pathogenetic course of AD. Here, we investigate the role of astrocyte in the mechanism of Aβ removal. ELISA and western blotting were performed to determine the ability of astrocyte to clear Aβ1-42. In this study, we demonstrated that cultured astrocytes removed extracellular oligomeric Aβ. However, cultured astrocytes from an AD mouse model showed less capacity to clear extracellular Aβ42 but with hyper-expression of NEP protein than normal astrocytes. In addition, LPS-induced inflammation rather than continuous Aβ stimuli inhibited the capacity of Aβ clearance by astrocytes indicating that inflammation possibly contributed to astrocytic dysfunction. Lastly, HOEC which exhibited anti-inflammatory effects restored the capacity of injured or aged astrocytes to clear Aβ. In conclusion, astrocytes have been shown to exert a direct role in Aβ clearance and undergo functional impair associated with inflammation in the pathogenesis of AD. Therefore, anti-inflammatory treatments aimed at restoring astrocyte functions may represent an appropriate approach to treat AD.
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Affiliation(s)
- Rui-Xuan Liu
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology130 Meilong Road, Shanghai 200237, China
| | - Cui Huang
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology130 Meilong Road, Shanghai 200237, China
| | - David A Bennett
- Department of Nutrition and Food Health, School of Public Health, Wuhan UniversityWuhan, China
- Rush Alzheimer’s Disease Center, Rush University Medical CenterChicago, IL, USA
| | - Honglin Li
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology130 Meilong Road, Shanghai 200237, China
| | - Rui Wang
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology130 Meilong Road, Shanghai 200237, China
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Abstract
The amyloid β-protein (Aβ) plays an indispensable role in the pathogenesis of Alzheimer disease (AD). Aβ is subject to proteolytic degradation by a diverse array of peptidases and proteinases, known collectively as Aβ-degrading proteases (AβDPs). A growing number of AβDPs have been identified that impact Aβ powerfully and in a surprising variety of ways. As such, AβDPs hold considerable therapeutic potential for the treatment and/or prevention of AD. Here, we critically review the relative merits of therapeutic strategies targeting AβDPs compared with current Aβ-lowering strategies focused on immunotherapies and pharmacological modulation of Aβ-producing enzymes. Several innovative advances have increased considerably the feasibility of delivering AβDPs to the brain or enhancing their activity in a non-invasive manner. We argue that therapies targeting AβDPs offer numerous potential advantages that should be explored through continued research into this promising field.
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Affiliation(s)
- Malcolm A Leissring
- Institute for Memory Impairments and Neurological Disorders (UCI MIND), University of California, Office: 5212 Natural Sciences II, Irvine, CA, 92697-1450, USA.
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Erinacine A-enriched Hericium erinaceus mycelium ameliorates Alzheimer's disease-related pathologies in APPswe/PS1dE9 transgenic mice. J Biomed Sci 2016; 23:49. [PMID: 27350344 PMCID: PMC4924315 DOI: 10.1186/s12929-016-0266-z] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Accepted: 06/15/2016] [Indexed: 12/26/2022] Open
Abstract
Background The fruiting body of Hericium erinaceus has been demonstrated to possess anti-dementia activity in mouse model of Alzheimer’s disease and people with mild cognitive impairment. However, the therapeutic potential of Hericium erinaceus mycelia on Alzheimer’s disease remains unclear. In this study, the effects of erinacine A-enriched Hericium erinaceus mycelia (HE-My) on the pathological changes in APPswe/PS1dE9 transgenic mouse model of Alzheimer’s disease are studied. Results After a 30 day oral administration to 5 month-old female APPswe/PS1dE9 transgenic mice, we found that HE-My and its ethanol extracts (HE-Et) attenuated cerebral Aβ plaque burden. It’s worth noting that the attenuated portion of a plaque is the non-compact structure. The level of insulin-degrading enzyme was elevated by both HE-My and HE-Et in cerebral cortex. On the other hand, the number of plaque-activated microglia and astrocytes in cerebral cortex and hippocampus were diminished, the ratio of nerve growth factor (NGF) to NGF precursor (proNGF) was increased and hippocampal neurogenesis was promoted after these administrations. All the mentioned benefits of these administrations may therefore improve the declined activity of daily living skill in APPswe/PS1dE9 transgenic mice. Conclusions These results highlight the therapeutic potential of HE-My and HE-Et on Alzheimer’s disease. Therefore, the effective components of HE-My and HE-Et are worth to be developed to become a therapeutic drug for Alzheimer’s disease.
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Structure of amyloid oligomers and their mechanisms of toxicities: Targeting amyloid oligomers using novel therapeutic approaches. Eur J Med Chem 2016; 114:41-58. [DOI: 10.1016/j.ejmech.2016.02.065] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Revised: 02/25/2016] [Accepted: 02/25/2016] [Indexed: 01/22/2023]
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Tang WJ. Targeting Insulin-Degrading Enzyme to Treat Type 2 Diabetes Mellitus. Trends Endocrinol Metab 2016; 27:24-34. [PMID: 26651592 PMCID: PMC4698235 DOI: 10.1016/j.tem.2015.11.003] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Revised: 11/03/2015] [Accepted: 11/04/2015] [Indexed: 10/22/2022]
Abstract
Insulin-degrading enzyme (IDE) selectively degrades peptides, such as insulin, amylin, and amyloid β (Aβ) that form toxic aggregates, to maintain proteostasis. IDE defects are linked to the development of type 2 diabetes mellitus (T2DM) and Alzheimer's disease (AD). Structural and biochemical analyses revealed the molecular basis for IDE-mediated destruction of amyloidogenic peptides and this information has been exploited to develop promising inhibitors of IDE to improve glucose homeostasis. However, the inhibition of IDE can also lead to glucose intolerance. In this review, I focus on recent advances regarding our understanding of the structure and function of IDE and the discovery of IDE inhibitors, as well as challenges in developing IDE-based therapy for human diseases, particularly T2DM.
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Affiliation(s)
- Wei-Jen Tang
- Ben-May Department for Cancer Research, the University of Chicago, Chicago, IL, USA.
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Grasso G, Satriano C, Milardi D. A neglected modulator of insulin-degrading enzyme activity and conformation: The pH. Biophys Chem 2015; 203-204:33-40. [PMID: 26025789 DOI: 10.1016/j.bpc.2015.05.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Revised: 05/19/2015] [Accepted: 05/21/2015] [Indexed: 12/16/2022]
Abstract
Insulin-degrading enzyme (IDE), a ubiquitously expressed zinc metalloprotease, has multiple activities in addition to insulin degradation and its malfunction is believed to connect type 2 diabetes with Alzheimer's disease. IDE has been found in many different cellular compartments, where it may experience significant physio-pathological pH variations. However, the exact role of pH variations on the interplay between enzyme conformations, stability, oligomerization state and catalysis is not understood. Here, we use ESI mass spectrometry, atomic force microscopy, surface plasmon resonance and circular dichroism to investigate the structure-activity relationship of IDE at different pH values. We show that acidic pH affects the ability of the enzyme to bind the substrate and decrease the stability of the protein by inducing an α-helical bundle conformation with a concomitant dissociation of multi-subunit IDE assemblies into monomeric units and loss of activity. These effects suggest a major role played by electrostatic forces in regulating multi-subunit enzyme assembly and function. Our results clearly indicate a pH dependent coupling among enzyme conformation, assembly and stability and suggest that cellular acidosis can have a large effect on IDE oligomerization state, inducing an enzyme inactivation and an altered insulin degradation that could have an impact on insulin signaling.
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Affiliation(s)
- Giuseppe Grasso
- Dipartimento di Scienze Chimiche, Università degli Studi di Catania, Viale Andrea Doria 6, 95125 Catania, Italy.
| | - Cristina Satriano
- Dipartimento di Scienze Chimiche, Università degli Studi di Catania, Viale Andrea Doria 6, 95125 Catania, Italy
| | - Danilo Milardi
- Istituto Biostrutture e Bioimmagini, CNR, Via P. Gaifami 18, 95126 Catania, Italy
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Kulikova AA, Makarov AA, Kozin SA. Roles of zinc ions and structural polymorphism of β-amyloid in the development of Alzheimer’s disease. Mol Biol 2015. [DOI: 10.1134/s0026893315020065] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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34
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Mitochondrial import and degradation of amyloid-β peptide. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2014; 1837:1069-74. [DOI: 10.1016/j.bbabio.2014.02.007] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Revised: 01/31/2014] [Accepted: 02/10/2014] [Indexed: 01/20/2023]
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35
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Cynis H, Funkelstein L, Toneff T, Mosier C, Ziegler M, Koch B, Demuth HU, Hook V. Pyroglutamate-amyloid-β and glutaminyl cyclase are colocalized with amyloid-β in secretory vesicles and undergo activity-dependent, regulated secretion. NEURODEGENER DIS 2014; 14:85-97. [PMID: 24943989 DOI: 10.1159/000358430] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Accepted: 01/07/2014] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND AND AIMS N-truncated pyroglutamate (pGlu)-amyloid-β [Aβ(3-40/42)] peptides are key components that promote Aβ peptide accumulation, leading to neurodegeneration and memory loss in Alzheimer's disease. Because Aβ deposition in the brain occurs in an activity-dependent manner, it is important to define the subcellular organelle for pGlu-Aβ(3-40/42) production by glutaminyl cyclase (QC) and their colocalization with full-length Aβ(1-40/42) peptides for activity-dependent, regulated secretion. Therefore, the objective of this study was to investigate the hypothesis that pGlu-Aβ and QC are colocalized with Aβ in dense-core secretory vesicles (DCSV) for activity-dependent secretion with neurotransmitters. METHODS Purified DCSV were assessed for pGlu-Aβ(3-40/42), Aβ(1-40/42), QC, and neurotransmitter secretion. Neuron-like chromaffin cells were analyzed for cosecretion of pGlu-Aβ, QC, Aβ, and neuropeptides. The cells were treated with a QC inhibitor, and pGlu-Aβ production was measured. Human neuroblastoma cells were also examined for pGlu-Aβ and QC secretion. RESULTS Isolated DCSV contain pGlu-Aβ(3-40/42), QC, and Aβ(1-40/42) with neuropeptide and catecholamine neurotransmitters. Cellular pGlu-Aβ and QC undergo activity-dependent cosecretion with Aβ and enkephalin and galanin neurotransmitters. The QC inhibitor decreased the level of secreted pGlu-Aβ. The human neuroblastoma cells displayed regulated secretion of pGlu-Aβ that was colocalized with QC. CONCLUSIONS pGlu-Aβ and QC are present with Aβ in DCSV and undergo activity-dependent, regulated cosecretion with neurotransmitters.
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Wang Y, Thinakaran G, Kar S. Overexpression of the IGF-II/M6P receptor in mouse fibroblast cell lines differentially alters expression profiles of genes involved in Alzheimer's disease-related pathology. PLoS One 2014; 9:e98057. [PMID: 24846272 PMCID: PMC4028253 DOI: 10.1371/journal.pone.0098057] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2014] [Accepted: 04/25/2014] [Indexed: 11/29/2022] Open
Abstract
Alzheimer’s disease (AD) is the most common type of senile dementia affecting elderly people. The processing of amyloid precursor protein (APP) leading to the generation of β-amyloid (Aβ) peptide contributes to neurodegeneration and development of AD pathology. The endocytic trafficking pathway, which comprises of the endosomes and lysosomes, acts as an important site for Aβ generation, and endocytic dysfunction has been linked to increased Aβ production and loss of neurons in AD brains. Since insulin-like growth factor-II (IGF-II) receptor plays a critical role in the transport of lysosomal enzymes from the trans-Golgi network to endosomes, it is likely that the receptor may have a role in regulating Aβ metabolism in AD pathology. However, very little is known on how altered levels of the IGF-II receptor can influence the expression/function of various molecules involved in AD pathology. To address this issue, we evaluated the expression profiles of 87 selected genes related to AD pathology in mouse fibroblast MS cells that are deficient in murine IGF-II receptor and corresponding MS9II cells overexpressing ∼500 times the human IGF-II receptors. Our results reveal that an elevation in IGF-II receptor levels alters the expression profiles of a number of genes including APP as well as enzymes regulating Aβ production, degradation and clearance mechanisms. Additionally, it influences the expression of various lysosomal enzymes and protein kinases that are involved in Aβ toxicity. IGF-II receptor overexpression also alters expression of several genes involved in intracellular signalling as well as cholesterol metabolism, which play a critical role in AD pathology. The altered gene profiles observed in this study closely match with the corresponding protein levels, with a few exceptions. These results, taken together, suggest that an elevation in IGF-II receptor levels can influence the expression profiles of transcripts as well as proteins that are involved in AD pathogenesis.
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Affiliation(s)
- Yanlin Wang
- Department of Psychiatry, University of Alberta, Edmonton, Alberta, Canada
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - Gopal Thinakaran
- Departments of Neurobiology, Neurology and Pathology, The University of Chicago, Chicago, Illinois, United States of America
| | - Satyabrata Kar
- Department of Psychiatry, University of Alberta, Edmonton, Alberta, Canada
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
- Department of Medicine (Neurology), University of Alberta, Edmonton, Alberta, Canada
- * E-mail:
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Kerridge C, Belyaev ND, Nalivaeva NN, Turner AJ. The Aβ-clearance protein transthyretin, like neprilysin, is epigenetically regulated by the amyloid precursor protein intracellular domain. J Neurochem 2014; 130:419-31. [PMID: 24528201 DOI: 10.1111/jnc.12680] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Revised: 01/23/2014] [Accepted: 02/03/2014] [Indexed: 12/20/2022]
Abstract
Proteolytic cleavage of the amyloid precursor protein (APP) by the successive actions of β- and γ-secretases generates several biologically active metabolites including the amyloid β-peptide (Aβ) and the APP intracellular domain (AICD). By analogy with the Notch signalling pathway, AICD has been proposed to play a role in transcriptional regulation. Among the cohort of genes regulated by AICD is the Aβ-degrading enzyme neprilysin (NEP). AICD binds to the NEP promoter causing transcriptional activation by competitive replacement with histone deacetylases (HDACs) leading to increased levels of NEP activity and hence increased Aβ clearance. We now show that the Aβ-clearance protein transthyretin (TTR) is also epigenetically up-regulated by AICD. Like NEP regulation, AICD derived specifically from the neuronal APP isoform, APP695 , binds directly to the TTR promoter displacing HDAC1 and HDAC3. Cell treatment with the tyrosine kinase inhibitor Gleevec (imatinib) or with the alkalizing agent NH4 Cl causes an accumulation of 'functional' AICD capable of up-regulating both TTR and NEP, leading to a reduction in total cellular Aβ levels. Pharmacological regulation of both NEP and TTR might represent a viable therapeutic target in Alzheimer's disease.
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Affiliation(s)
- Caroline Kerridge
- School of Molecular & Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK
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38
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The clearance of misfolded proteins in neurodegenerative diseases by zinc metalloproteases: An inorganic perspective. Coord Chem Rev 2014. [DOI: 10.1016/j.ccr.2013.10.008] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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39
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Leissring MA, Turner AJ. Regulation of distinct pools of amyloid β-protein by multiple cellular proteases. ALZHEIMERS RESEARCH & THERAPY 2013; 5:37. [PMID: 23953275 PMCID: PMC3978621 DOI: 10.1186/alzrt194] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Alzheimer’s disease (AD) is a progressive, age-related neurodegenerative disorder characterized by extracellular and intracellular deposition of the amyloid β-protein (Aβ). The study of rare, familial forms of AD has shown that sustained elevations in the production of Aβ (either all forms or specific pathogenic variants thereof) are sufficient to trigger the full spectrum of cognitive and histopathological features of the disease. Although the exact cause or causes remain unknown, emerging evidence suggests that impairments in the clearance of Aβ, after it is produced, may underlie the vast majority of sporadic AD cases. This review focuses on Aβ-degrading proteases (AβDPs), which have emerged as particularly important mediators of Aβ clearance. A wide variety of proteases that – by virtue of their particular regional and subcellular localization profiles – define distinct pools of Aβ have been identified. Different pools of Aβ, in turn, may contribute differentially to the pathogenesis of the disease. The study of individual AβDPs, therefore, promises to offer new insights into the mechanistic basis of AD pathogenesis and, ultimately, may facilitate the development of effective methods for its prevention or treatment or both.
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Affiliation(s)
- Malcolm A Leissring
- Department of Neuroscience, Mayo Clinic, Birdsall Building, Room 117, Jacksonville, FL 32224, USA
| | - Anthony J Turner
- School of Molecular & Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
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40
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Saido T, Leissring MA. Proteolytic degradation of amyloid β-protein. Cold Spring Harb Perspect Med 2013; 2:a006379. [PMID: 22675659 DOI: 10.1101/cshperspect.a006379] [Citation(s) in RCA: 253] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The amyloid β-protein (Aβ) is subject to proteolytic degradation by a diverse array of peptidases and proteinases, known collectively as Aβ-degrading proteases (AβDPs). A growing number of AβDPs have been identified, which, under physiological and/or pathophysiological conditions, contribute significantly to the determination of endogenous cerebral Aβ levels. Despite more than a decade of investigation, the complete set of AβDPs remains to be established, and our understanding of even well-established AβDPs is incomplete. Nevertheless, the study of known AβDPs has contributed importantly to our understanding of the molecular pathogenesis of Alzheimer disease (AD) and has inspired the development of several novel therapeutic approaches to the regulation of cerebral Aβ levels. In this article, we discuss the general features of Aβ degradation and introduce the best-characterized AβDPs, focusing on their diverse properties and the numerous conceptual insights that have emerged from the study of each.
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Affiliation(s)
- Takaomi Saido
- Riken Brain Science Institute, Saitamo 351-0198, Japan
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41
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Pacheco-Quinto J, Herdt A, Eckman CB, Eckman EA. Endothelin-converting enzymes and related metalloproteases in Alzheimer's disease. J Alzheimers Dis 2013; 33 Suppl 1:S101-10. [PMID: 22903130 DOI: 10.3233/jad-2012-129043] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The efficient clearance of amyloid-β (Aβ) is essential to modulate levels of the peptide in the brain and to prevent it from accumulating in senile plaques, a hallmark of Alzheimer's disease (AD) pathology.We and others have shown that failure in Aβ catabolism can produce elevations in Aβ concentration similar to those observed in familial forms of AD. Based on the available evidence, it remains plausible that in late-onset AD, disturbances in the activity of Aβ degrading enzymes could induce Aβ accumulation, and that this increase could result in AD pathology. The following review presents a historical perspective of the parallel discovery of three vasopeptidases (neprilysin and endothelin-converting enzymes-1 and -2) as important Aβ degrading enzymes. The recognition of the role of these vasopeptidases in Aβ degradation, beyond bringing to light a possible explanation of how cardiovascular risk factors may influence AD risk, highlights a possible risk of the use of inhibitors of these enzymes for other clinical indications such as hypertension. We will discuss in detail the experiments conducted to assess the impact of vasopeptidase deficiency (through pharmacological inhibition or genetic mutation) on Aβ accumulation, as well as the cooperative effect of multiple Aβ degrading enzymes to regulate the concentration of the peptide at multiple sites, both intracellular and extracellular, throughout the brain.
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Affiliation(s)
- Javier Pacheco-Quinto
- Biomedical Research Institute of New Jersey, MidAtlantic Neonatology Associates, and Atlantic Health System, Morristown, NJ, USA
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42
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Syrén PO. The solution of nitrogen inversion in amidases. FEBS J 2013; 280:3069-83. [DOI: 10.1111/febs.12241] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2012] [Revised: 03/06/2013] [Accepted: 03/08/2013] [Indexed: 01/06/2023]
Affiliation(s)
- Per-Olof Syrén
- Institute of Technical Biochemistry; University of Stuttgart; Germany
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43
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Park SM, Kim KS. Proteolytic clearance of extracellular α-synuclein as a new therapeutic approach against Parkinson disease. Prion 2012; 7:121-6. [PMID: 23154633 DOI: 10.4161/pri.22850] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Many neurodegenerative diseases such as Alzheimer disease and Parkinson disease show similar characteristics. They typically show deposits of protein aggregates, the formation of which is considered important in their pathogenesis. Recently, aggregation-prone proteins have been shown to spread between cells and so may contribute to the pathogenesis of diseases like prion disease. Such a pathogenesis pathway is possibly common to many neurodegenerative diseases. If confirmed, it could allow the development of therapeutic interventions against many such diseases. In Parkinson disease, α-synuclein, a major component of cytosolic protein inclusions named Lewy body, has been shown to be released and taken up by cells, which may facilitate its progressive pathological spreading between cells. Accordingly, inhibition of spreading by targeting extracellular α-synuclein may represent a new therapy against Parkinson disease. Research into the intercellular spreading of extracellular protein aggregations of α-synuclein and its clearance pathway are reviewed here with a focus on the proteolytic clearance pathway as a therapeutic target for the treatment of Parkinson disease. Considering the similar characteristics of aggregation-prone proteins, these clearance systems might allow treatment of other neurodegenerative diseases beyond Parkinson disease.
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Affiliation(s)
- Sang Myun Park
- Department of Pharmacology, Neuroscience Graduate Program, Chronic Inflammatory Disease Research Center, Ajou University School of Medicine, Suwon, South Korea.
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Jayaraman A, Carroll JC, Morgan TE, Lin S, Zhao L, Arimoto JM, Murphy MP, Beckett TL, Finch CE, Brinton RD, Pike CJ. 17β-estradiol and progesterone regulate expression of β-amyloid clearance factors in primary neuron cultures and female rat brain. Endocrinology 2012; 153:5467-79. [PMID: 22962256 PMCID: PMC3473201 DOI: 10.1210/en.2012-1464] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2012] [Accepted: 08/06/2012] [Indexed: 02/04/2023]
Abstract
The accumulation of β-amyloid protein (Aβ) is a key risk factor in the development of Alzheimer's disease. The ovarian sex steroid hormones 17β-estradiol (E(2)) and progesterone (P(4)) have been shown to regulate Aβ accumulation, although the underlying mechanism(s) remain to be fully elucidated. In this study, we investigate the effects of E(2) and P(4) treatment on the expression levels of Aβ clearance factors including insulin-degrading enzyme, neprilysin, endothelin-converting enzyme 1 and 2, angiotensin-converting enzyme, and transthyretin, both in primary neuron cultures and female rat brains. Our results show that E(2) and P(4) affect the expression levels of several Aβ clearance factors in dose- and time-dependent manners. Most notably, expression of insulin-degrading enzyme is significantly increased by both hormones in cultured neurons and in vivo and is inversely associated with the soluble Aβ levels in vivo. These findings further define sex steroid hormone actions involved in regulation of Aβ, a relationship potentially important to therapeutic approaches aimed at reducing risk of Alzheimer's disease.
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Affiliation(s)
- Anusha Jayaraman
- Neuroscience Graduate Program, University of Southern California, Los Angeles, California 90089, USA
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Protein clearance mechanisms of alpha-synuclein and amyloid-Beta in lewy body disorders. Int J Alzheimers Dis 2012; 2012:391438. [PMID: 23133788 PMCID: PMC3485523 DOI: 10.1155/2012/391438] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2012] [Accepted: 08/30/2012] [Indexed: 12/30/2022] Open
Abstract
Protein clearance is critical for the maintenance of the integrity of neuronal cells, and there is accumulating evidence that in most-if not all-neurodegenerative disorders, impaired protein clearance fundamentally contributes to functional and structural alterations eventually leading to clinical symptoms. Dysfunction of protein clearance leads to intra- and extraneuronal accumulation of misfolded proteins and aggregates. The pathological hallmark of Lewy body disorders (LBDs) is the abnormal accumulation of misfolded proteins such as alpha-synuclein (Asyn) and amyloid-beta (Abeta) in a specific subset of neurons, which in turn has been related to deficits in protein clearance. In this paper we will highlight common intraneuronal (including autophagy and unfolded protein stress response) and extraneuronal (including interaction of neurons with astrocytes and microglia, phagocytic clearance, autoimmunity, cerebrospinal fluid transport, and transport across the blood-brain barrier) protein clearance mechanisms, which may be altered across the spectrum of LBDs. A better understanding of the pathways underlying protein clearance-in particular of Asyn and Abeta-in LBDs may result in the identification of novel biomarkers for disease onset and progression and of new therapeutic targets.
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Abdul-Hay SO, Sahara T, McBride M, Kang D, Leissring MA. Identification of BACE2 as an avid ß-amyloid-degrading protease. Mol Neurodegener 2012; 7:46. [PMID: 22986058 PMCID: PMC3470943 DOI: 10.1186/1750-1326-7-46] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Accepted: 08/16/2012] [Indexed: 11/10/2022] Open
Abstract
Background Proteases that degrade the amyloid ß-protein (Aß) have emerged as key players in the etiology and potential treatment of Alzheimer’s disease (AD), but it is unlikely that all such proteases have been identified. To discover new Aß-degrading proteases (AßDPs), we conducted an unbiased, genome-scale, functional cDNA screen designed to identify proteases capable of lowering net Aß levels produced by cells, which were subsequently characterized for Aß-degrading activity using an array of downstream assays. Results The top hit emerging from the screen was ß-site amyloid precursor protein-cleaving enzyme 2 (BACE2), a rather unexpected finding given the well-established role of its close homolog, BACE1, in the production of Aß. BACE2 is known to be capable of lowering Aß levels via non-amyloidogenic processing of APP. However, in vitro, BACE2 was also found to be a particularly avid AßDP, with a catalytic efficiency exceeding all known AßDPs except insulin-degrading enzyme (IDE). BACE1 was also found to degrade Aß, albeit ~150-fold less efficiently than BACE2. Aß is cleaved by BACE2 at three peptide bonds—Phe19-Phe20, Phe20-Ala21, and Leu34-Met35—with the latter cleavage site being the initial and principal one. BACE2 overexpression in cultured cells was found to lower net Aß levels to a greater extent than multiple, well-established AßDPs, including neprilysin (NEP) and endothelin-converting enzyme-1 (ECE1), while showing comparable effectiveness to IDE. Conclusions This study identifies a new functional role for BACE2 as a potent AßDP. Based on its high catalytic efficiency, its ability to degrade Aß intracellularly, and other characteristics, BACE2 represents a particulary strong therapeutic candidate for the treatment or prevention of AD.
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Affiliation(s)
- Samer O Abdul-Hay
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Road, Birdsall Bldg,, Rm, 117, Jacksonville, FL 32224, USA
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47
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Grasso G, Giuffrida ML, Rizzarelli E. Metallostasis and amyloid β-degrading enzymes. Metallomics 2012; 4:937-49. [DOI: 10.1039/c2mt20105d] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Mulder SD, Veerhuis R, Blankenstein MA, Nielsen HM. The effect of amyloid associated proteins on the expression of genes involved in amyloid-β clearance by adult human astrocytes. Exp Neurol 2012; 233:373-9. [DOI: 10.1016/j.expneurol.2011.11.001] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2011] [Revised: 10/25/2011] [Accepted: 11/01/2011] [Indexed: 11/24/2022]
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Abstract
A promising strategy to delay and perhaps prevent Alzheimer's disease (AD) is to identify the age-related changes that put the brain at risk for the disease. A significant normal age change known to result in tissue-specific dysfunction is the depletion of sex hormones. In women, menopause results in a relatively rapid loss of estradiol and progesterone. In men, aging is associated with a comparatively gradual yet significant decrease in testosterone. We review a broad literature that indicates age-related losses of estrogens in women and testosterone in men are risk factors for AD. Both estrogens and androgens exert a wide range of protective actions that improve multiple aspects of neural health, suggesting that hormone therapies have the potential to combat AD pathogenesis. However, translation of experimental findings into effective therapies has proven challenging. One emerging treatment option is the development of novel hormone mimetics termed selective estrogen and androgen receptor modulators. Continued research of sex hormones and their roles in the aging brain is expected to yield valuable approaches to reducing the risk of AD.
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Affiliation(s)
- Anna M. Barron
- USC Davis School of Gerontology, University of Southern California, Los Angeles, CA 90089 USA
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, 153-8902 Japan
| | - Christian J. Pike
- USC Davis School of Gerontology, University of Southern California, Los Angeles, CA 90089 USA
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Barron AM, Pike CJ. Sex hormones, aging, and Alzheimer's disease. Front Biosci (Elite Ed) 2012. [PMID: 22201929 DOI: 10.2741/434] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
A promising strategy to delay and perhaps prevent Alzheimer's disease (AD) is to identify the age-related changes that put the brain at risk for the disease. A significant normal age change known to result in tissue-specific dysfunction is the depletion of sex hormones. In women, menopause results in a relatively rapid loss of estradiol and progesterone. In men, aging is associated with a comparatively gradual yet significant decrease in testosterone. We review a broad literature that indicates age-related losses of estrogens in women and testosterone in men are risk factors for AD. Both estrogens and androgens exert a wide range of protective actions that improve multiple aspects of neural health, suggesting that hormone therapies have the potential to combat AD pathogenesis. However, translation of experimental findings into effective therapies has proven challenging. One emerging treatment option is the development of novel hormone mimetics termed selective estrogen and androgen receptor modulators. Continued research of sex hormones and their roles in the aging brain is expected to yield valuable approaches to reducing the risk of AD.
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Affiliation(s)
- Anna M Barron
- USC Davis School of Gerontology, University of Southern California, Los Angeles, CA 90089 USA
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