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Svedružić ŽM, Vrbnjak K, Martinović M, Miletić V. Structural Analysis of the Simultaneous Activation and Inhibition of γ-Secretase Activity in the Development of Drugs for Alzheimer's Disease. Pharmaceutics 2021; 13:pharmaceutics13040514. [PMID: 33917979 PMCID: PMC8068388 DOI: 10.3390/pharmaceutics13040514] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 03/31/2021] [Accepted: 04/06/2021] [Indexed: 12/24/2022] Open
Abstract
Significance: The majority of the drugs which target membrane-embedded protease γ-secretase show an unusual biphasic activation–inhibition dose-response in cells, model animals, and humans. Semagacestat and avagacestat are two biphasic drugs that can facilitate cognitive decline in patients with Alzheimer’s disease. Initial mechanistic studies showed that the biphasic drugs, and pathogenic mutations, can produce the same type of changes in γ-secretase activity. Results: DAPT, semagacestat LY-411,575, and avagacestat are four drugs that show different binding constants, and a biphasic activation–inhibition dose-response for amyloid-β-40 products in SH-SY5 cells. Multiscale molecular dynamics studies have shown that all four drugs bind to the most mobile parts in the presenilin structure, at different ends of the 29 Å long active site tunnel. The biphasic dose-response assays are a result of the modulation of γ-secretase activity by the concurrent binding of multiple drug molecules at each end of the active site tunnel. The drugs activate γ-secretase by facilitating the opening of the active site tunnel, when the rate-limiting step is the tunnel opening, and the formation of the enzyme–substrate complex. The drugs inhibit γ-secretase as uncompetitive inhibitors by binding next to the substrate, to dynamic enzyme structures which regulate processive catalysis. The drugs can modulate the production of different amyloid-β catalytic intermediates by penetration into the active site tunnel, to different depths, with different flexibility and different binding affinity. Conclusions: Biphasic drugs and pathogenic mutations can affect the same dynamic protein structures that control processive catalysis. Successful drug-design strategies must incorporate transient changes in the γ-secretase structure in the development of specific modulators of its catalytic activity.
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Affiliation(s)
- Željko M. Svedružić
- Department of Biotechnology, University of Rijeka, 51000 Rijeka, Croatia; (K.V.); (M.M.)
- Laboratory for Medical Biochemistry, Psychiatric Hospital Rab, Kampor 224, 51280 Rab, Croatia
- Correspondence:
| | - Katarina Vrbnjak
- Department of Biotechnology, University of Rijeka, 51000 Rijeka, Croatia; (K.V.); (M.M.)
- Laboratory for Mechanisms of Cell Transformation (VIB-KU Leuven), ON IV Herestraat—Box 912, 3000 Leuven, Belgium
| | - Manuel Martinović
- Department of Biotechnology, University of Rijeka, 51000 Rijeka, Croatia; (K.V.); (M.M.)
| | - Vedran Miletić
- Department of Informatics, University of Rijeka, 51000 Rijeka, Croatia;
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2
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Wolfe MS. Probing Mechanisms and Therapeutic Potential of γ-Secretase in Alzheimer's Disease. MOLECULES (BASEL, SWITZERLAND) 2021; 26:molecules26020388. [PMID: 33450968 PMCID: PMC7828430 DOI: 10.3390/molecules26020388] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 01/02/2021] [Accepted: 01/10/2021] [Indexed: 12/14/2022]
Abstract
The membrane-embedded γ-secretase complex carries out hydrolysis within the lipid bilayer in proteolyzing nearly 150 different membrane protein substrates. Among these substrates, the amyloid precursor protein (APP) has been the most studied, as generation of aggregation-prone amyloid β-protein (Aβ) is a defining feature of Alzheimer's disease (AD). Mutations in APP and in presenilin, the catalytic component of γ-secretase, cause familial AD, strong evidence for a pathogenic role of Aβ. Substrate-based chemical probes-synthetic peptides and peptidomimetics-have been critical to unraveling the complexity of γ-secretase, and small drug-like inhibitors and modulators of γ-secretase activity have been essential for exploring the potential of the protease as a therapeutic target for Alzheimer's disease. Such chemical probes and therapeutic prototypes will be reviewed here, with concluding commentary on the future directions in the study of this biologically important protease complex and the translation of basic findings into therapeutics.
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Affiliation(s)
- Michael S Wolfe
- Department of Medicinal Chemistry, University of Kansas, 1567 Irving Hill Road, GLH-2115, Lawrence, KS 66045, USA
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3
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Lakey-Beitia J, Burillo AM, Penna GL, Hegde ML, Rao K. Polyphenols as Potential Metal Chelation Compounds Against Alzheimer's Disease. J Alzheimers Dis 2021; 82:S335-S357. [PMID: 32568200 PMCID: PMC7809605 DOI: 10.3233/jad-200185] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Alzheimer's disease (AD) is the most common neurodegenerative disease affecting more than 50 million people worldwide. The pathology of this multifactorial disease is primarily characterized by the formation of amyloid-β (Aβ) aggregates; however, other etiological factors including metal dyshomeostasis, specifically copper (Cu), zinc (Zn), and iron (Fe), play critical role in disease progression. Because these transition metal ions are important for cellular function, their imbalance can cause oxidative stress that leads to cellular death and eventual cognitive decay. Importantly, these transition metal ions can interact with the amyloid-β protein precursor (AβPP) and Aβ42 peptide, affecting Aβ aggregation and increasing its neurotoxicity. Considering how metal dyshomeostasis may substantially contribute to AD, this review discusses polyphenols and the underlying chemical principles that may enable them to act as natural chelators. Furthermore, polyphenols have various therapeutic effects, including antioxidant activity, metal chelation, mitochondrial function, and anti-amyloidogenic activity. These combined therapeutic effects of polyphenols make them strong candidates for a moderate chelation-based therapy for AD.
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Affiliation(s)
- Johant Lakey-Beitia
- Centre for Biodiversity and Drug Discovery, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología (INDICASAT AIP), Clayton, City of Knowledge, Panama
| | - Andrea M. Burillo
- Centre for Biodiversity and Drug Discovery, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología (INDICASAT AIP), Clayton, City of Knowledge, Panama
| | - Giovanni La Penna
- National Research Council, Institute of Chemistry of Organometallic Compounds, Sesto Fiorentino (FI), Italy
| | - Muralidhar L. Hegde
- Department of Radiation Oncology, Houston Methodist Research Institute, Houston, TX, USA
- Department of Neurosurgery, Center for Neuroregeneration, Houston Methodist Research Institute, Houston, TX, USA
- Weill Medical College of Cornell University, New York, NY, USA
| | - K.S. Rao
- Centre for Neuroscience, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología (INDICASAT AIP), Clayton, City of Knowledge, Panama
- Zhongke Jianlan Medical Institute, Hangzhou, Republic of China
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4
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Cam M, Durieu E, Bodin M, Manousopoulou A, Koslowski S, Vasylieva N, Barnych B, Hammock BD, Bohl B, Koch P, Omori C, Yamamoto K, Hata S, Suzuki T, Karg F, Gizzi P, Erakovic Haber V, Bencetic Mihaljevic V, Tavcar B, Portelius E, Pannee J, Blennow K, Zetterberg H, Garbis SD, Auvray P, Gerber H, Fraering J, Fraering PC, Meijer L. Induction of Amyloid-β42 Production by Fipronil and Other Pyrazole Insecticides. J Alzheimers Dis 2019; 62:1663-1681. [PMID: 29504531 DOI: 10.3233/jad-170875] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Generation of amyloid-β peptides (Aβs) by proteolytic cleavage of the amyloid-β protein precursor (AβPP), especially increased production of Aβ42/Aβ43 over Aβ40, and their aggregation as oligomers and plaques, represent a characteristic feature of Alzheimer's disease (AD). In familial AD (FAD), altered Aβ production originates from specific mutations of AβPP or presenilins 1/2 (PS1/PS2), the catalytic subunits of γ-secretase. In sporadic AD, the origin of altered production of Aβs remains unknown. We hypothesize that the 'human chemical exposome' contains products able to favor the production of Aβ42/Aβ43 over Aβ40 and shorter Aβs. To detect such products, we screened a library of 3500 + compounds in a cell-based assay for enhanced Aβ42/Aβ43 production. Nine pyrazole insecticides were found to induce a β- and γ-secretase-dependent, 3-10-fold increase in the production of extracellular Aβ42 in various cell lines and neurons differentiated from induced pluripotent stem cells derived from healthy and FAD patients. Immunoprecipitation/mass spectrometry analyses showed increased production of Aβs cleaved at positions 42/43, and reduced production of peptides cleaved at positions 38 and shorter. Strongly supporting a direct effect on γ-secretase activity, pyrazoles shifted the cleavage pattern of another γ-secretase substrate, alcadeinα, and shifted the cleavage of AβPP by highly purified γ-secretase toward Aβ42/Aβ43. Focusing on fipronil, we showed that some of its metabolites, in particular the persistent fipronil sulfone, also favor the production of Aβ42/Aβ43 in both cell-based and cell-free systems. Fipronil administered orally to mice and rats is known to be metabolized rapidly, mostly to fipronil sulfone, which stably accumulates in adipose tissue and brain. In conclusion, several widely used pyrazole insecticides enhance the production of toxic, aggregation prone Aβ42/Aβ43 peptides, suggesting the possible existence of environmental "Alzheimerogens" which may contribute to the initiation and propagation of the amyloidogenic process in sporadic AD.
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Affiliation(s)
- Morgane Cam
- ManRos Therapeutics, Centre de Perharidy, Roscoff, Bretagne, France
| | - Emilie Durieu
- ManRos Therapeutics, Centre de Perharidy, Roscoff, Bretagne, France
| | - Marion Bodin
- ManRos Therapeutics, Centre de Perharidy, Roscoff, Bretagne, France
| | - Antigoni Manousopoulou
- Faculty of Medicine, Cancer Sciences and Clinical and Experimental Medicine, University of Southampton, Southampton, UK
| | - Svenja Koslowski
- ManRos Therapeutics, Centre de Perharidy, Roscoff, Bretagne, France.,C.RIS Pharma, Parc Technopolitain, Atalante Saint Malo, Saint Malo, France
| | - Natalia Vasylieva
- Department of Entomology and Nematology and UCD Comprehensive Cancer Center, University of California, Davis, CA, USA
| | - Bogdan Barnych
- Department of Entomology and Nematology and UCD Comprehensive Cancer Center, University of California, Davis, CA, USA
| | - Bruce D Hammock
- Department of Entomology and Nematology and UCD Comprehensive Cancer Center, University of California, Davis, CA, USA
| | - Bettina Bohl
- Institute of Reconstructive Neurobiology, University of Bonn, Bonn, Germany
| | - Philipp Koch
- Institute of Reconstructive Neurobiology, University of Bonn, Bonn, Germany.,Central Institute of Mental Health, University of Heidelberg/ Medical, Faculty Mannheim and Hector Institut for Translational Brain Research (HITBR gGmbH), Mannheim, Germany
| | - Chiori Omori
- Laboratory of Neuroscience, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan.,Department of Integrated Bioscience, Graduate School of Frontier Sciences, University of Tokyo, Kashiwa, Japan
| | - Kazuo Yamamoto
- Department of Integrated Bioscience, Graduate School of Frontier Sciences, University of Tokyo, Kashiwa, Japan
| | - Saori Hata
- Laboratory of Neuroscience, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
| | - Toshiharu Suzuki
- Laboratory of Neuroscience, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
| | - Frank Karg
- HPC INTERNATIONAL SAS and Atlantis Développement SAS, Noyal-Châtillon sur Seiche, Saint-Erblon, France
| | - Patrick Gizzi
- Plate-forme TechMedILL, UMR 7242, ESBS - Pôle API, Illkirch cedex, France
| | | | | | | | - Erik Portelius
- Clinical Neurochemical Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| | - Josef Pannee
- Clinical Neurochemical Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden.,Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, University of Gothenburg, Mölndal, Sweden
| | - Kaj Blennow
- Clinical Neurochemical Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden.,Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, University of Gothenburg, Mölndal, Sweden
| | - Henrik Zetterberg
- Clinical Neurochemical Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden.,Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, University of Gothenburg, Mölndal, Sweden.,Department of Molecular Neuroscience, UCL Institute of Neurology, Queen Square, London, UK.,UK Dementia Research Institute, London, UK
| | - Spiros D Garbis
- Faculty of Medicine, Cancer Sciences and Clinical and Experimental Medicine, University of Southampton, Southampton, UK
| | - Pierrick Auvray
- C.RIS Pharma, Parc Technopolitain, Atalante Saint Malo, Saint Malo, France
| | - Hermeto Gerber
- Foundation Eclosion, Switzerland.,Campus Biotech Innovation Park, Geneva, Switzerland.,Department of Biology, University of Fribourg, Fribourg, Switzerland
| | - Jeremy Fraering
- Foundation Eclosion, Switzerland.,Campus Biotech Innovation Park, Geneva, Switzerland
| | - Patrick C Fraering
- Foundation Eclosion, Switzerland.,Campus Biotech Innovation Park, Geneva, Switzerland
| | - Laurent Meijer
- ManRos Therapeutics, Centre de Perharidy, Roscoff, Bretagne, France
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5
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Verheijen BM, Stevens JAA, Gentier RJG, van 't Hekke CD, van den Hove DLA, Hermes DJHP, Steinbusch HWM, Ruijter JM, Grimm MOW, Haupenthal VJ, Annaert W, Hartmann T, van Leeuwen FW. Paradoxical effects of mutant ubiquitin on Aβ plaque formation in an Alzheimer mouse model. Neurobiol Aging 2018; 72:62-71. [PMID: 30216939 DOI: 10.1016/j.neurobiolaging.2018.08.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 07/03/2018] [Accepted: 08/10/2018] [Indexed: 01/08/2023]
Abstract
Amyloid-β (Aβ) plaques are a prominent pathological hallmark of Alzheimer's disease (AD). They consist of aggregated Aβ peptides, which are generated through sequential proteolytic processing of the transmembrane protein amyloid precursor protein (APP) and several Aβ-associated factors. Efficient clearance of Aβ from the brain is thought to be important to prevent the development and progression of AD. The ubiquitin-proteasome system (UPS) is one of the major pathways for protein breakdown in cells and it has been suggested that impaired UPS-mediated removal of protein aggregates could play an important role in the pathogenesis of AD. To study the effects of an impaired UPS on Aβ pathology in vivo, transgenic APPSwe/PS1ΔE9 mice (APPPS1) were crossed with transgenic mice expressing mutant ubiquitin (UBB+1), a protein-based inhibitor of the UPS. Surprisingly, the APPPS1/UBB+1 crossbreed showed a remarkable decrease in Aβ plaque load during aging. Further analysis showed that UBB+1 expression transiently restored PS1-NTF expression and γ-secretase activity in APPPS1 mice. Concurrently, UBB+1 decreased levels of β-APP-CTF, which is a γ-secretase substrate. Although UBB+1 reduced Aβ pathology in APPPS1 mice, it did not improve the behavioral deficits in these animals.
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Affiliation(s)
- Bert M Verheijen
- Department of Psychiatry and Neuropsychology, Faculty of Health Medicine and Life Sciences, Maastricht University, Maastricht, The Netherlands
| | - Jo A A Stevens
- Department of Psychiatry and Neuropsychology, Faculty of Health Medicine and Life Sciences, Maastricht University, Maastricht, The Netherlands
| | - Romina J G Gentier
- Department of Psychiatry and Neuropsychology, Faculty of Health Medicine and Life Sciences, Maastricht University, Maastricht, The Netherlands
| | - Christian D van 't Hekke
- Department of Psychiatry and Neuropsychology, Faculty of Health Medicine and Life Sciences, Maastricht University, Maastricht, The Netherlands
| | - Daniel L A van den Hove
- Department of Psychiatry and Neuropsychology, Faculty of Health Medicine and Life Sciences, Maastricht University, Maastricht, The Netherlands; Department of Psychiatry, Psychosomatics and Psychotherapy, University of Würzburg, Würzburg, Germany
| | - Denise J H P Hermes
- Department of Psychiatry and Neuropsychology, Faculty of Health Medicine and Life Sciences, Maastricht University, Maastricht, The Netherlands
| | - Harry W M Steinbusch
- Department of Psychiatry and Neuropsychology, Faculty of Health Medicine and Life Sciences, Maastricht University, Maastricht, The Netherlands
| | - Jan M Ruijter
- Department of Medical Biology, Academic Medical Center, Amsterdam, The Netherlands
| | - Marcus O W Grimm
- Deutsches Institut für Demenzprävention, University of Saarland, Experimental Neurology, Homburg, Germany
| | - Viola J Haupenthal
- Deutsches Institut für Demenzprävention, University of Saarland, Experimental Neurology, Homburg, Germany
| | - Wim Annaert
- VIB Center for Brain and Disease Research and KU Leuven, Gasthuisberg, Belgium
| | - Tobias Hartmann
- Deutsches Institut für Demenzprävention, University of Saarland, Experimental Neurology, Homburg, Germany
| | - Fred W van Leeuwen
- Department of Psychiatry and Neuropsychology, Faculty of Health Medicine and Life Sciences, Maastricht University, Maastricht, The Netherlands.
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6
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Allicin ameliorates cognitive impairment in APP/PS1 mice via Suppressing oxidative stress by Blocking JNK Signaling Pathways. Tissue Cell 2018; 50:89-95. [DOI: 10.1016/j.tice.2017.11.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Revised: 11/16/2017] [Accepted: 11/26/2017] [Indexed: 01/02/2023]
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7
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Portelius E, Durieu E, Bodin M, Cam M, Pannee J, Leuxe C, Mabondzo A, Oumata N, Galons H, Lee JY, Chang YT, Stϋber K, Koch P, Fontaine G, Potier MC, Manousopoulou A, Garbis SD, Covaci A, Van Dam D, De Deyn P, Karg F, Flajolet M, Omori C, Hata S, Suzuki T, Blennow K, Zetterberg H, Meijer L. Specific Triazine Herbicides Induce Amyloid-β42 Production. J Alzheimers Dis 2018; 54:1593-1605. [PMID: 27589520 DOI: 10.3233/jad-160310] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Proteolytic cleavage of the amyloid-β protein precursor (AβPP) by secretases leads to extracellular release of amyloid-β (Aβ) peptides. Increased production of Aβ42 over Aβ40 and aggregation into oligomers and plaques constitute an Alzheimer's disease (AD) hallmark. Identifying products of the 'human chemical exposome' (HCE) able to induce Aβ42 production may be a key to understanding some of the initiating causes of AD and to generate non-genetic, chemically-induced AD animal models. A cell model was used to screen HCE libraries for Aβ42 inducers. Out of 3500+ compounds, six triazine herbicides were found that induced a β- and γ-secretases-dependent, 2-10 fold increase in the production of extracellular Aβ42 in various cell lines, primary neuronal cells, and neurons differentiated from human-induced pluripotent stem cells (iPSCs). Immunoprecipitation/mass spectrometry analyses show enhanced production of Aβ peptides cleaved at positions 42/43, and reduced production of peptides cleaved at positions 38 and lower, a characteristic of AD. Neurons derived from iPSCs obtained from a familial AD (FAD) patient (AβPP K724N) produced more Aβ42 versus Aβ40 than neurons derived from healthy controls iPSCs (AβPP WT). Triazines enhanced Aβ42 production in both control and AD iPSCs-derived neurons. Triazines also shifted the cleavage pattern of alcadeinα, another γ-secretase substrate, suggesting a direct effect of triazines on γ-secretase activity. In conclusion, several widely used triazines enhance the production of toxic, aggregation prone Aβ42/Aβ43 amyloids, suggesting the possible existence of environmental "Alzheimerogens" which may contribute to the initiation and propagation of the amyloidogenic process in late-onset AD.
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Affiliation(s)
- Erik Portelius
- Clinical Neurochemical Laboratory, Institute of Neuroscience & Physiology, University of Gothenburg, Göteborg, Sweden
| | - Emilie Durieu
- ManRos Therapeutics, Centre de Perharidy, Roscoff, France
| | - Marion Bodin
- ManRos Therapeutics, Centre de Perharidy, Roscoff, France
| | - Morgane Cam
- ManRos Therapeutics, Centre de Perharidy, Roscoff, France
| | - Josef Pannee
- Clinical Neurochemical Laboratory, Institute of Neuroscience & Physiology, University of Gothenburg, Göteborg, Sweden
| | - Charlotte Leuxe
- Service de Pharmacologie et d'Immunoanalyse, IBITECS, CEA, Université Paris-Saclay, F-91191 Gif-sur-Yvette Cedex, France
| | - Aloϊse Mabondzo
- Service de Pharmacologie et d'Immunoanalyse, IBITECS, CEA, Université Paris-Saclay, F-91191 Gif-sur-Yvette Cedex, France
| | - Nassima Oumata
- ManRos Therapeutics, Centre de Perharidy, Roscoff, France
| | - Hervé Galons
- ManRos Therapeutics, Centre de Perharidy, Roscoff, France.,Laboratoire de Pharmacochimie, INSERM U1022, Université Paris-Descartes, Paris, France
| | - Jung Yeol Lee
- Department of Chemistry, National University of Singapore, Laboratory of Bioimaging Probe Development, Biopolis, Singapore
| | - Young-Tae Chang
- Department of Chemistry, National University of Singapore, Laboratory of Bioimaging Probe Development, Biopolis, Singapore
| | - Kathrin Stϋber
- Institute of Reconstructive Neurobiology, University of Bonn, Bonn, Germany
| | - Philipp Koch
- Institute of Reconstructive Neurobiology, University of Bonn, Bonn, Germany
| | - Gaëlle Fontaine
- Sorbonne Universités, UPMC Université Paris 06 UMR S1127, Inserm U1127, CNRS UMR7225, ICM, Paris, France
| | - Marie-Claude Potier
- Sorbonne Universités, UPMC Université Paris 06 UMR S1127, Inserm U1127, CNRS UMR7225, ICM, Paris, France
| | - Antigoni Manousopoulou
- Center for Proteomic Research, Institute for Life Sciences, Cancer and Clinical Experimental Science Units, School of Medicine, University of Southampton, Southampton, UK
| | - Spiros D Garbis
- Center for Proteomic Research, Institute for Life Sciences, Cancer and Clinical Experimental Science Units, School of Medicine, University of Southampton, Southampton, UK
| | - Adrian Covaci
- Toxicological Center, University of Antwerp, Wilrijk, Belgium
| | - Debby Van Dam
- Laboratory of Neurochemistry & Behaviour, Department of Biomedical Sciences, Institute Born-Bunge, Wilrijk, Belgium.,University of Groningen, University Medical Center Groningen, Department of Neurology & Alzheimer Research Center, Groningen, The Netherlands
| | - Peter De Deyn
- Laboratory of Neurochemistry & Behaviour, Department of Biomedical Sciences, Institute Born-Bunge, Wilrijk, Belgium.,University of Groningen, University Medical Center Groningen, Department of Neurology & Alzheimer Research Center, Groningen, The Netherlands
| | - Frank Karg
- HPC INTERNATIONAL SAS, Noyal-Châtillon sur Seiche, Saint-Erblon, France
| | - Marc Flajolet
- Laboratory of Molecular & Cellular Neuroscience, The Rockefeller University, New York, NY, USA
| | - Chiori Omori
- Laboratory of Neuroscience, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
| | - Saori Hata
- Laboratory of Neuroscience, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
| | - Toshiharu Suzuki
- Laboratory of Neuroscience, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
| | - Kaj Blennow
- Clinical Neurochemical Laboratory, Institute of Neuroscience & Physiology, University of Gothenburg, Göteborg, Sweden
| | - Henrik Zetterberg
- Clinical Neurochemical Laboratory, Institute of Neuroscience & Physiology, University of Gothenburg, Göteborg, Sweden.,UCL Institute of Neurology, London, UK
| | - Laurent Meijer
- ManRos Therapeutics, Centre de Perharidy, Roscoff, France
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8
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Translational inhibition of APP by Posiphen: Efficacy, pharmacodynamics, and pharmacokinetics in the APP/PS1 mouse. ALZHEIMERS & DEMENTIA-TRANSLATIONAL RESEARCH & CLINICAL INTERVENTIONS 2018; 4:37-45. [PMID: 29955650 PMCID: PMC6021259 DOI: 10.1016/j.trci.2017.12.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Introduction Translational inhibition of amyloid precursor protein (APP) by Posiphen has been shown to reduce APP and its fragments in cell culture, animal models, and mildly cognitively impaired patients, making it a promising drug candidate for the treatment of Alzheimer's disease. Methods We used a mouse model of Alzheimer's disease (APP/presenilin-1) to examine Posiphen's efficacy, pharmacodynamics, and pharmacokinetics. Results Posiphen treatment normalized impairments in spatial working memory, contextual fear learning, and synaptic function in APP/presenilin-1 mice, without affecting their visual acuity, motor skills, or motivation and without affecting wild-type mice. Posiphen had a prolonged effect in reducing APP and all related peptides for at least 9 hours after the last dose. Its concentration was higher in the brain than in plasma, and the most abundant metabolite was N8-norPosiphen. Discussion This is the first study demonstrating the therapeutic efficacy of inhibiting the translation of APP and its fragments in an Alzheimer's disease model.
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9
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Agholme L, Clarin M, Gkanatsiou E, Kettunen P, Chebli J, Brinkmalm G, Blennow K, Bergström P, Portelius E, Zetterberg H. Low-dose γ-secretase inhibition increases secretion of Aβ peptides and intracellular oligomeric Aβ. Mol Cell Neurosci 2017; 85:211-219. [PMID: 29104140 DOI: 10.1016/j.mcn.2017.10.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 10/24/2017] [Accepted: 10/31/2017] [Indexed: 10/18/2022] Open
Abstract
γ-Secretase inhibitors have been considered promising drug candidates against Alzheimer's disease (AD) due to their ability to reduce amyloid-β (Aβ) production. However, clinical trials have been halted due to lack of clinical efficacy and/or side effects. Recent in vitro studies suggest that low doses of γ-secretase inhibitors may instead increase Aβ production. Using a stem cell-derived human model of cortical neurons and low doses of the γ-secretase inhibitor DAPT, the effects on a variety of Aβ peptides were studied using mass spectrometry. One major focus was to develop a novel method for specific detection of oligomeric Aβ (oAβ), and this was used to study the effects of low-dose γ-secretase inhibitor treatment on intracellular oAβ accumulation. Low-dose treatment (2 and 20nM) with DAPT increased the secretion of several Aβ peptides, especially Aβx-42. Furthermore, using the novel method for oAβ detection, we found that 2nM DAPT treatment of cortical neurons resulted in increased oAβ accumulation. Thus, low dose-treatment with DAPT causes both increased production of long, aggregation-prone Aβ peptides and accumulation of intracellular Aβ oligomers, both believed to contribute to AD pathology.
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Affiliation(s)
- Lotta Agholme
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, The Sahlgrenska Academy at University of Gothenburg, S-405 30 Gothenburg, Sweden.
| | - Marcus Clarin
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, The Sahlgrenska Academy at University of Gothenburg, S-405 30 Gothenburg, Sweden; Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, The Sahlgrenska Academy at University of Gothenburg, S-431 80 Mölndal, Sweden
| | - Eleni Gkanatsiou
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, The Sahlgrenska Academy at University of Gothenburg, S-431 80 Mölndal, Sweden
| | - Petronella Kettunen
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, The Sahlgrenska Academy at University of Gothenburg, S-405 30 Gothenburg, Sweden
| | - Jasmine Chebli
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, The Sahlgrenska Academy at University of Gothenburg, S-405 30 Gothenburg, Sweden
| | - Gunnar Brinkmalm
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, The Sahlgrenska Academy at University of Gothenburg, S-431 80 Mölndal, Sweden; Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal S-431 80, Sweden
| | - Kaj Blennow
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, The Sahlgrenska Academy at University of Gothenburg, S-431 80 Mölndal, Sweden; Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal S-431 80, Sweden
| | - Petra Bergström
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, The Sahlgrenska Academy at University of Gothenburg, S-405 30 Gothenburg, Sweden
| | - Erik Portelius
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, The Sahlgrenska Academy at University of Gothenburg, S-431 80 Mölndal, Sweden; Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal S-431 80, Sweden
| | - Henrik Zetterberg
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, The Sahlgrenska Academy at University of Gothenburg, S-431 80 Mölndal, Sweden; Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal S-431 80, Sweden; Institute of Neurology, Department of Molecular Neuroscience, University College London, WC1N 3BG, UK; UK Dementia Research Institute, University College London, London WC1N 3BG, UK
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10
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Raven F, Ward JF, Zoltowska KM, Wan Y, Bylykbashi E, Miller SJ, Shen X, Choi SH, Rynearson KD, Berezovska O, Wagner SL, Tanzi RE, Zhang C. Soluble Gamma-secretase Modulators Attenuate Alzheimer's β-amyloid Pathology and Induce Conformational Changes in Presenilin 1. EBioMedicine 2017; 24:93-101. [PMID: 28919280 PMCID: PMC5652037 DOI: 10.1016/j.ebiom.2017.08.028] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 08/18/2017] [Accepted: 08/31/2017] [Indexed: 11/29/2022] Open
Abstract
A central pathogenic event of Alzheimer's disease (AD) is the accumulation of the Aβ42 peptide, which is generated from amyloid-β precursor protein (APP) via cleavages by β- and γ-secretase. We have developed a class of soluble 2-aminothiazole γ-secretase modulators (SGSMs) that preferentially decreases Aβ42 levels. However, the effects of SGSMs in AD animals and cells expressing familial AD mutations, as well as the mechanism of γ-secretase modulation remain largely unknown. Here, a representative of this SGSM scaffold, SGSM-36, was investigated using animals and cells expressing FAD mutations. SGSM-36 preferentially reduced Aβ42 levels without affecting either α- and β-secretase processing of APP nor Notch processing. Furthermore, an allosteric site was identified within the γ-secretase complex that allowed access of SGSM-36 using cell-based, fluorescence lifetime imaging microscopy analysis. Collectively, these studies provide mechanistic insights regarding SGSMs of this class and reinforce their therapeutic potential in AD. A novel class soluble 2-aminothiazole γ-secretase modulators (SGSMs) are characterized as potential therapeutics for AD. A representative compound, SGSM-36, preferentially decreases Aβ42 levels using animal and cell models of AD. An allosteric site was identified within γ-secretase to be accessible by SGSM-36.
Alzheimer's disease (AD) is a devastating neurodegenerative disorder and there is currently no treatment to slow or halt disease progression. Considerable evidence shows that the primary pathological event leading to AD is the production and accumulation of Aβ42 peptide. We have developed a class of soluble 2-aminothiazole γ-secretase modulators (SGSMs) that preferentially decreases Aβ42 levels. The presented studies have primarily elucidated the mechanisms by which our SGSMs decrease Aβ42 levels and attenuate β-amyloid pathology. The results of these experiments will be useful toward the ongoing efforts toward the development of an effective therapy for the treatment and prevention of AD.
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Affiliation(s)
- Frank Raven
- Genetics and Aging Research Unit, MassGeneral Institute for Neurodegenerative Diseases (MIND), Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129-2060, USA; Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen 9747 AG, The Netherlands
| | - Joseph F Ward
- Genetics and Aging Research Unit, MassGeneral Institute for Neurodegenerative Diseases (MIND), Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129-2060, USA
| | - Katarzyna M Zoltowska
- Alzheimer Research Unit, MassGeneral Institute for Neurodegenerative Diseases (MIND), Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129-2060, USA
| | - Yu Wan
- Genetics and Aging Research Unit, MassGeneral Institute for Neurodegenerative Diseases (MIND), Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129-2060, USA; Department of Neurology, Qingdao Municipal Hospital, Qingdao University, PR China
| | - Enjana Bylykbashi
- Genetics and Aging Research Unit, MassGeneral Institute for Neurodegenerative Diseases (MIND), Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129-2060, USA
| | - Sean J Miller
- Genetics and Aging Research Unit, MassGeneral Institute for Neurodegenerative Diseases (MIND), Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129-2060, USA
| | - Xunuo Shen
- Genetics and Aging Research Unit, MassGeneral Institute for Neurodegenerative Diseases (MIND), Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129-2060, USA
| | - Se Hoon Choi
- Genetics and Aging Research Unit, MassGeneral Institute for Neurodegenerative Diseases (MIND), Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129-2060, USA
| | - Kevin D Rynearson
- Department of Neurosciences, University of California, La Jolla, San Diego, CA 92093-0624, USA
| | - Oksana Berezovska
- Alzheimer Research Unit, MassGeneral Institute for Neurodegenerative Diseases (MIND), Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129-2060, USA
| | - Steven L Wagner
- Department of Neurosciences, University of California, La Jolla, San Diego, CA 92093-0624, USA; Research Biologist, VA San Diego Healthcare System, La Jolla, CA, 92161, United States.
| | - Rudolph E Tanzi
- Genetics and Aging Research Unit, MassGeneral Institute for Neurodegenerative Diseases (MIND), Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129-2060, USA.
| | - Can Zhang
- Genetics and Aging Research Unit, MassGeneral Institute for Neurodegenerative Diseases (MIND), Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129-2060, USA.
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11
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Yin J, Zhao F, Chojnacki JE, Fulp J, Klein WL, Zhang S, Zhu X. NLRP3 Inflammasome Inhibitor Ameliorates Amyloid Pathology in a Mouse Model of Alzheimer's Disease. Mol Neurobiol 2017; 55:1977-1987. [PMID: 28255908 DOI: 10.1007/s12035-017-0467-9] [Citation(s) in RCA: 137] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 02/20/2017] [Indexed: 12/25/2022]
Abstract
The activation of the NLRP3 inflammasome signaling pathway plays an important role in the neuroinflammation in Alzheimer's disease (AD). In this study, we investigated the effects of JC-124, a rationally designed NLRP3 inflammasome inhibitor, on AD-related deficits in CRND8 APP transgenic mice (TgCRND8). We first demonstrated increased formation and activation of NLRP3 inflammasome in TgCRND8 mice compared to non-transgenic littermate controls, which was inhibited by the treatment with JC-124. Importantly, JC-124 treatment led to decreased levels of Aβ deposition and decreased levels of soluble and insoluble Aβ1-42 in the brain of CRND8 mice which was accompanied by reduced β-cleavage of APP, reduced activation of microglia but enhanced astrocytosis. Oxidative stress was decreased and synaptophysin was increased in the CRND8 mice after JC-124 treatment, demonstrating a neuroprotective effect. Overall, these data demonstrated beneficial effects of JC-124 as a specific NLRP3 inflammasome inhibitor in AD mouse model and supported the further development of NLRP3 inflammasome inhibitors as a viable option for AD therapeutics.
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Affiliation(s)
- Jun Yin
- Department of Pathophysiology, School of Basic Medical Sciences, Wuhan University, Wuhan, Hubei, China.,Department of Pathology, Case Western Reserve University, Cleveland, OH, USA
| | - Fanpeng Zhao
- Department of Pathology, Case Western Reserve University, Cleveland, OH, USA
| | - Jeremy E Chojnacki
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, VA, 23298, USA
| | - Jacob Fulp
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, VA, 23298, USA
| | - William L Klein
- Department of Neurobiology, Northwestern University, Evanston, IL, USA
| | - Shijun Zhang
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, VA, 23298, USA.
| | - Xiongwei Zhu
- Department of Pathology, Case Western Reserve University, Cleveland, OH, USA.
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12
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Kumar V, Sami N, Kashav T, Islam A, Ahmad F, Hassan MI. Protein aggregation and neurodegenerative diseases: From theory to therapy. Eur J Med Chem 2016; 124:1105-1120. [DOI: 10.1016/j.ejmech.2016.07.054] [Citation(s) in RCA: 97] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Revised: 07/20/2016] [Accepted: 07/22/2016] [Indexed: 12/23/2022]
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13
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Carroll CM, Li YM. Physiological and pathological roles of the γ-secretase complex. Brain Res Bull 2016; 126:199-206. [PMID: 27133790 DOI: 10.1016/j.brainresbull.2016.04.019] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Revised: 04/19/2016] [Accepted: 04/27/2016] [Indexed: 12/27/2022]
Abstract
Gamma-secretase (GS) is an enzyme complex that cleaves numerous substrates, and it is best known for cleaving amyloid precursor protein (APP) to form amyloid-beta (Aβ) peptides. Aberrant cleavage of APP can lead to Alzheimer's disease, so much research has been done to better understand GS structure and function in hopes of developing therapeutics for Alzheimer's. Therefore, most of the attention in this field has been focused on developing modulators that reduce pathogenic forms of Aβ while leaving Notch and other GS substrates intact, but GS provides multiple avenues of modulation that could improve AD pathology. GS has complex regulation, through its essential subunits and other associated proteins, providing other targets for AD drugs. Therapeutics can also alter GS trafficking and thereby improve cognition, or move beyond Aβ entirely, effecting Notch and neural stem cells. GS also cleaves substrates that affect synaptic morphology and function, presenting another window by which GS modulation could improve AD pathology. Taken together, GS presents a unique cross road for neural processes and an ideal target for AD therapeutics.
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Affiliation(s)
- Courtney M Carroll
- Chemical Biology Program, Memorial Sloan Kettering Cancer Center, NY, United States; Program of Neuroscience, Weill Graduate School of Medical Sciences of Cornell University, NY, United States.
| | - Yue-Ming Li
- Chemical Biology Program, Memorial Sloan Kettering Cancer Center, NY, United States; Program of Neuroscience, Weill Graduate School of Medical Sciences of Cornell University, NY, United States; Program of Pharmacology, Weill Graduate School of Medical Sciences of Cornell University, NY, United States
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14
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Li N, Liu K, Qiu Y, Ren Z, Dai R, Deng Y, Qing H. Effect of Presenilin Mutations on APP Cleavage; Insights into the Pathogenesis of FAD. Front Aging Neurosci 2016; 8:51. [PMID: 27014058 PMCID: PMC4786568 DOI: 10.3389/fnagi.2016.00051] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Accepted: 02/26/2016] [Indexed: 11/13/2022] Open
Abstract
Alzheimer disease (AD) is characterized by progressive memory loss, reduction in cognitive functions, and damage to the brain. The β-amyloid precursor protein can be sequentially cleaved by β- secretase and γ-secretase. Mutations in the presenilin1(PS1) are the most common cause of Familial Alzheimer’s disease (FAD). PS1 mutations can alter the activity of γ-secretase on the cleavage of the β-amyloid precursor protein, causing increased Aβ production. Previous studies show that the βAPP-C-terminal fragment is first cleaved by β-scretase, primarily generating long fragments of Aβ48 and Aβ49, followed by the stepwise cleavage of every three amino acid residues at the C terminus, resulting in Aβ48-, 45-, 42 line and Aβ49-, 46-, 43-, 40 line. Here, we used LC-MS/MS to analyze unique peptides IAT, VVIA, ITL, TVI, IVI through sequential cleavage, combined with ELISA to test the level of Aβ42 and Aβ40 for validation. The results show that most FAD mutant PS1 can alter the level of Aβ42 and Aβ40 monitored by the Aβ42/Aβ40 ratio. Among them, six mutants (I143T, H163P, S170F, Q223R, M233V, and G384A) affect the Aβ42/40 ratio through both Aβ49-40 and Aβ48-38 lines; L166P through decreasing the Aβ49-40 line, six mutants (I143V, M146V, G217A, E280A, L381V, and L392V) through increasing the Aβ48-42 line. More importantly, we found some mutations can affect the γ-secretase cleavage preference of α-CTF and β-CTF. In conclusion, we found that the FAD PS1 mutations mainly increase the generation of Aβ42 by decreasing the cleavage of Aβ42–Aβ38 and Aβ43–Aβ40.
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Affiliation(s)
- Nuomin Li
- School of Life Science, Beijing Institute of Technology Beijing, China
| | - Kefu Liu
- School of Life Science, Beijing Institute of Technology Beijing, China
| | - Yunjie Qiu
- School of Life Science, Beijing Institute of Technology Beijing, China
| | - Zehui Ren
- School of Life Science, Beijing Institute of Technology Beijing, China
| | - Rongji Dai
- School of Life Science, Beijing Institute of Technology Beijing, China
| | - Yulin Deng
- School of Life Science, Beijing Institute of Technology Beijing, China
| | - Hong Qing
- School of Life Science, Beijing Institute of Technology Beijing, China
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15
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Baranello RJ, Bharani KL, Padmaraju V, Chopra N, Lahiri DK, Greig NH, Pappolla MA, Sambamurti K. Amyloid-beta protein clearance and degradation (ABCD) pathways and their role in Alzheimer's disease. Curr Alzheimer Res 2015; 12:32-46. [PMID: 25523424 PMCID: PMC4820400 DOI: 10.2174/1567205012666141218140953] [Citation(s) in RCA: 210] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Revised: 11/16/2014] [Accepted: 12/05/2014] [Indexed: 11/22/2022]
Abstract
Amyloid-β proteins (Aβ) of 42 (Aβ42) and 40 aa (Aβ40) accumulate as senile plaques (SP) and cerebrovascular amyloid protein deposits that are defining diagnostic features of Alzheimer's disease (AD). A number of rare mutations linked to familial AD (FAD) on the Aβ precursor protein (APP), Presenilin-1 (PS1), Presenilin- 2 (PS2), Adamalysin10, and other genetic risk factors for sporadic AD such as the ε4 allele of Apolipoprotein E (ApoE-ε4) foster the accumulation of Aβ and also induce the entire spectrum of pathology associated with the disease. Aβ accumulation is therefore a key pathological event and a prime target for the prevention and treatment of AD. APP is sequentially processed by β-site APP cleaving enzyme (BACE1) and γ-secretase, a multisubunit PS1/PS2-containing integral membrane protease, to generate Aβ. Although Aβ accumulates in all forms of AD, the only pathways known to be affected in FAD increase Aβ production by APP gene duplication or via base substitutions on APP and γ-secretase subunits PS1 and PS2 that either specifically increase the yield of the longer Aβ42 or both Aβ40 and Aβ42. However, the vast majority of AD patients accumulate Aβ without these known mutations. This led to proposals that impairment of Aβ degradation or clearance may play a key role in AD pathogenesis. Several candidate enzymes, including Insulin-degrading enzyme (IDE), Neprilysin (NEP), Endothelin-converting enzyme (ECE), Angiotensin converting enzyme (ACE), Plasmin, and Matrix metalloproteinases (MMPs) have been identified and some have even been successfully evaluated in animal models. Several studies also have demonstrated the capacity of γ-secretase inhibitors to paradoxically increase the yield of Aβ and we have recently established that the mechanism is by skirting Aβ degradation. This review outlines major cellular pathways of Aβ degradation to provide a basis for future efforts to fully characterize the panel of pathways responsible for Aβ turnover.
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Affiliation(s)
| | | | | | | | | | | | | | - Kumar Sambamurti
- Department of Neurosciences, Medical University of South Carolina, 173 Ashley Avenue, BSB 403, Charleston, SC 29425, USA.
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Wolfe MS. Unlocking truths of γ-secretase in Alzheimer's disease: what is the translational potential? FUTURE NEUROLOGY 2014; 9:419-429. [PMID: 26146489 DOI: 10.2217/fnl.14.35] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Considerable evidence, particularly from genetics, points to the aggregation-prone amyloid β-peptide as a pathogenic entity in Alzheimer's disease. Hence, the proteases that produce this peptide from its precursor protein have been prime targets for the development of potential therapeutics. One of these proteases, γ-secretase, has been a particular focus. Many inhibitors and modulators of this membrane-embedded protease complex have been identified, with some brought into late-stage clinical trials, where they have spectacularly failed. The reasons for these failures will be discussed, along with recent findings on the mechanism of γ-secretase and of Alzheimer-causing mutations that may suggest new strategies for targeting this enzyme.
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Affiliation(s)
- Michael S Wolfe
- Center for Neurologic Disease, Brigham & Women's Hospital, Harvard Medical School, Boston, MA 02115, USA; Tel.: +1 617 525 5511
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