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Kinger S, Jagtap YA, Kumar P, Choudhary A, Prasad A, Prajapati VK, Kumar A, Mehta G, Mishra A. Proteostasis in neurodegenerative diseases. Adv Clin Chem 2024; 121:270-333. [PMID: 38797543 DOI: 10.1016/bs.acc.2024.04.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
Proteostasis is essential for normal function of proteins and vital for cellular health and survival. Proteostasis encompasses all stages in the "life" of a protein, that is, from translation to functional performance and, ultimately, to degradation. Proteins need native conformations for function and in the presence of multiple types of stress, their misfolding and aggregation can occur. A coordinated network of proteins is at the core of proteostasis in cells. Among these, chaperones are required for maintaining the integrity of protein conformations by preventing misfolding and aggregation and guide those with abnormal conformation to degradation. The ubiquitin-proteasome system (UPS) and autophagy are major cellular pathways for degrading proteins. Although failure or decreased functioning of components of this network can lead to proteotoxicity and disease, like neuron degenerative diseases, underlying factors are not completely understood. Accumulating misfolded and aggregated proteins are considered major pathomechanisms of neurodegeneration. In this chapter, we have described the components of three major branches required for proteostasis-chaperones, UPS and autophagy, the mechanistic basis of their function, and their potential for protection against various neurodegenerative conditions, like Alzheimer's, Parkinson's, and Huntington's disease. The modulation of various proteostasis network proteins, like chaperones, E3 ubiquitin ligases, proteasome, and autophagy-associated proteins as therapeutic targets by small molecules as well as new and unconventional approaches, shows promise.
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Affiliation(s)
- Sumit Kinger
- Cellular and Molecular Neurobiology Unit, Indian Institute of Technology Jodhpur, Rajasthan, India
| | - Yuvraj Anandrao Jagtap
- Cellular and Molecular Neurobiology Unit, Indian Institute of Technology Jodhpur, Rajasthan, India
| | - Prashant Kumar
- Cellular and Molecular Neurobiology Unit, Indian Institute of Technology Jodhpur, Rajasthan, India
| | - Akash Choudhary
- Cellular and Molecular Neurobiology Unit, Indian Institute of Technology Jodhpur, Rajasthan, India
| | - Amit Prasad
- School of Biosciences and Bioengineering, Indian Institute of Technology Mandi, Mandi, Himachal Pradesh, India
| | - Vijay Kumar Prajapati
- Department of Biochemistry, University of Delhi South Campus, Dhaula Kuan, New Delhi, India
| | - Amit Kumar
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Simrol, Indore, Madhya Pradesh, India
| | - Gunjan Mehta
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Telangana, India
| | - Amit Mishra
- Cellular and Molecular Neurobiology Unit, Indian Institute of Technology Jodhpur, Rajasthan, India.
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2
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Role of Neddylation in Neurodegenerative Diseases. NEUROSCI 2022. [DOI: 10.3390/neurosci3040038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Neurodegenerative diseases are characterized by progressive loss of neurons in specific regions of the brain. Neuronal death is often associated with the accumulation of misfolded proteins due to genetic mutations or abnormal protein homeostasis. An essential mechanism for regulating the clearance of misfolded proteins is neddylation, a post-translational modification closely related to ubiquitination. Neddylation is brought about by conjugating neural precursor cell-expressed developmentally downregulated protein 8 (NEDD8) to target substrates through a cascade of cellular events. Neddylation is crucial for many biological processes, and dysfunctional neddylation is implicated in several neurodegenerative diseases. This review discusses the current understanding of the role of neddylation pathways in neurodegenerative disorders and the emergence of neddylation signaling as a potential target for drug discovery and development in neurodegenerative diseases.
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3
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Leduc-Gaudet JP, Hussain SN, Gouspillou G. Parkin: A potential target to promote healthy aging. J Physiol 2022; 600:3405-3421. [PMID: 35691026 DOI: 10.1113/jp282567] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Accepted: 06/08/2022] [Indexed: 11/08/2022] Open
Abstract
Parkin is an E3 ubiquitin ligase mostly known for its role in regulating the removal of defective mitochondria via mitophagy. However, increasing experimental evidence that Parkin regulates several other aspects of mitochondrial biology in addition to its role in mitophagy has emerged over the past two decades. Indeed, Parkin has been shown to regulate mitochondrial biogenesis and dynamics and mitochondrial-derived vesicle formation, suggesting that Parkin plays key roles in maintaining healthy mitochondria. While Parkin is commonly described as a cytosolic E3 ubiquitin ligase, Parkin was also detected in other cellular compartments, including the nucleus, where it regulates transcription factors and acts as a transcription factor itself. New evidence also suggests that Parkin overexpression can be leveraged to delay aging. In D. melanogaster, for example, Parkin overexpression extends lifespan. In mammals, Parkin overexpression delays hallmarks of aging in several tissues and cell types. Parkin overexpression also confers protection in various models of cellular senescence and neurological disorders closely associated with aging, such as Alzheimer's and Parkinson's diseases. Recently, Parkin overexpression has also been shown to suppress tumor growth. In this review, we discuss newly emerging biological roles of Parkin as a modulator of cellular homeostasis, survival, and healthy aging, and we explore potential mechanisms through which Parkin exerts its beneficial effects on cellular health. Abstract figure legend Parkin: A potential target to promote healthy aging Illustration of key aspects of Parkin biology, including Parkin function and cellular localization and key roles in the regulation of mitochondrial quality control. The organs and systems in which Parkin overexpression was shown to exert protective effects relevant to the promotion of healthy aging are highlighted in the black rectangle at the bottom of the Figure. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Jean-Philippe Leduc-Gaudet
- Department of Biomedical Sciences, Veneto Institute of Molecular Medicine, University of Padova, Padova, Italy.,Meakins-Christie Laboratories, Department of Medicine, McGill University, Montréal, QC, Canada.,Translational Research in Respiratory Diseases Program, Research Institute of the McGill University Health Centre, Montréal, QC, Canada.,Département des sciences de l'activité physique, Faculté des sciences, Université du Québec à Montréal (UQAM), Montréal, QC, Canada
| | - Sabah Na Hussain
- Meakins-Christie Laboratories, Department of Medicine, McGill University, Montréal, QC, Canada.,Translational Research in Respiratory Diseases Program, Research Institute of the McGill University Health Centre, Montréal, QC, Canada
| | - Gilles Gouspillou
- Meakins-Christie Laboratories, Department of Medicine, McGill University, Montréal, QC, Canada.,Département des sciences de l'activité physique, Faculté des sciences, Université du Québec à Montréal (UQAM), Montréal, QC, Canada
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4
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Amyloid beta oligomers-induced parkin aggravates ER stress-mediated cell death through a positive feedback loop. Neurochem Int 2022; 155:105312. [DOI: 10.1016/j.neuint.2022.105312] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 02/08/2022] [Accepted: 02/20/2022] [Indexed: 11/24/2022]
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5
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Murillo-González FE, García-Aguilar R, Vega L, Elizondo G. Regulation of Parkin expression as the key balance between neural survival and cancer cell death. Biochem Pharmacol 2021; 190:114650. [PMID: 34111426 DOI: 10.1016/j.bcp.2021.114650] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 06/02/2021] [Accepted: 06/04/2021] [Indexed: 11/25/2022]
Abstract
Parkin is a cytosolic E3 ubiquitin ligase that plays an important role in neuroprotection by targeting several proteins to be degraded by the 26S proteasome. Its dysfunction has been associated not only with Parkinson's disease (PD) but also with other neurodegenerative pathologies, such as Alzheimer's disease and Huntington's disease. More recently, Parkin has been identified as a tumor suppressor gene implicated in cancer development. Due to the important roles that this E3 ubiquitin ligase plays in cellular homeostasis, its expression, activity, and turnover are tightly regulated. Several reviews have addressed Parkin regulation; however, genetic and epigenetic regulation have been excluded. In addition to posttranslational modifications (PTMs), this review examines the regulatory mechanisms that control Parkin function through gene expression, epigenetic regulation, and degradation. Furthermore, the consequences of disrupting these regulatory processes on human health are discussed.
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Affiliation(s)
| | | | - Libia Vega
- Department of Toxicology, CINVESTAV-IPN, Av. IPN 2508, C.P. 07360 Mexico City, Mexico
| | - Guillermo Elizondo
- Department of Cellular Biology, CINVESTAV-IPN, Av. IPN 2508, C.P. 07360 Mexico City, Mexico.
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6
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Huang Z, Yan Q, Wang Y, Zou Q, Li J, Liu Z, Cai Z. Role of Mitochondrial Dysfunction in the Pathology of Amyloid-β. J Alzheimers Dis 2021; 78:505-514. [PMID: 33044180 DOI: 10.3233/jad-200519] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Mitochondrial dysfunction has been widely reported in several neurodegenerative disorders, including in the brains of patients with Alzheimer's disease (AD), Parkinson's disease, and Huntington disease. An increasing number of studies have implicated altered glucose and energy metabolism in patients with AD. There is compelling evidence of abnormalities in some of the key mitochondrial enzymes involved in glucose metabolism, including the pyruvate dehydrogenase and α-ketoglutarate dehydrogenase complexes, which play a great significance role in the pathogenesis of AD. Changes in some of the enzyme activities of the mitochondria found in AD have been linked with the pathology of amyloid-β (Aβ). This review highlights the role of mitochondrial function in the production and clearance of Aβ and how the pathology of Aβ leads to a decrease in energy metabolism by affecting mitochondrial function.
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Affiliation(s)
- Zhenting Huang
- Chongqing Key Laboratory of Neurodegenerative Diseases, Chongqing, Chongqing, China.,Department of Neurology, Chongqing General Hospital, University of Chinese Academy of Sciences, Chongqing, Chongqing, China
| | - Qian Yan
- Chongqing Key Laboratory of Neurodegenerative Diseases, Chongqing, Chongqing, China.,Department of Neurology, Chongqing General Hospital, University of Chinese Academy of Sciences, Chongqing, Chongqing, China.,Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, China
| | - Yangyang Wang
- Chongqing Key Laboratory of Neurodegenerative Diseases, Chongqing, Chongqing, China.,Department of Neurology, Chongqing General Hospital, University of Chinese Academy of Sciences, Chongqing, Chongqing, China
| | - Qian Zou
- Chongqing Key Laboratory of Neurodegenerative Diseases, Chongqing, Chongqing, China.,Department of Neurology, Chongqing General Hospital, University of Chinese Academy of Sciences, Chongqing, Chongqing, China
| | - Jing Li
- Chongqing Key Laboratory of Neurodegenerative Diseases, Chongqing, Chongqing, China.,Department of Neurology, Chongqing General Hospital, University of Chinese Academy of Sciences, Chongqing, Chongqing, China
| | - Zhou Liu
- Department of Neurology, Affiliated Hospital of Guangdong Medical University, Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases, Zhanjiang, Guangdong, China
| | - Zhiyou Cai
- Chongqing Key Laboratory of Neurodegenerative Diseases, Chongqing, Chongqing, China.,Department of Neurology, Chongqing General Hospital, University of Chinese Academy of Sciences, Chongqing, Chongqing, China
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7
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Liu X, Moussa C. Regulatory Role of Ubiquitin Specific Protease-13 (USP13) in Misfolded Protein Clearance in Neurodegenerative Diseases. Neuroscience 2021; 460:161-166. [PMID: 33577955 DOI: 10.1016/j.neuroscience.2021.02.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 02/02/2021] [Accepted: 02/03/2021] [Indexed: 12/14/2022]
Abstract
Ubiquitin Specific Protease (USP)-13 is a de-ubiquitinase member of the cysteine-dependent protease superfamily that cleaves ubiquitin off protein substrates to reverse ubiquitin-mediated protein degradation. Several findings implicate USPs in neurodegeneration. Ubiquitin targets proteins to major degradation pathways, including the proteasome and the lysosome. In melanoma cells, USP13 regulates the degradation of several proteins primarily via ubiquitination and de-ubiquitination. However, the significance of USP13 in regulating protein clearance in neurodegeneration is largely unknown. This mini-review summarizes the most recent evidence pertaining to the role of USP13 in protein clearance via autophagy and the proteasome in neurodegenerative diseases.
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Affiliation(s)
- Xiaoguang Liu
- Translational Neurotherapeutics Program, Laboratory for Dementia and Parkinsonism, Department of Neurology, Georgetown University Medical Center, Building D, Room 265, 4000 Reservoir Road, NW, Washington DC 20057, USA.
| | - Charbel Moussa
- Translational Neurotherapeutics Program, Laboratory for Dementia and Parkinsonism, Department of Neurology, Georgetown University Medical Center, Building D, Room 265, 4000 Reservoir Road, NW, Washington DC 20057, USA.
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8
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Vaillant-Beuchot L, Mary A, Pardossi-Piquard R, Bourgeois A, Lauritzen I, Eysert F, Kinoshita PF, Cazareth J, Badot C, Fragaki K, Bussiere R, Martin C, Mary R, Bauer C, Pagnotta S, Paquis-Flucklinger V, Buée-Scherrer V, Buée L, Lacas-Gervais S, Checler F, Chami M. Accumulation of amyloid precursor protein C-terminal fragments triggers mitochondrial structure, function, and mitophagy defects in Alzheimer's disease models and human brains. Acta Neuropathol 2021; 141:39-65. [PMID: 33079262 PMCID: PMC7785558 DOI: 10.1007/s00401-020-02234-7] [Citation(s) in RCA: 110] [Impact Index Per Article: 36.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 09/03/2020] [Accepted: 10/01/2020] [Indexed: 02/07/2023]
Abstract
Several lines of recent evidence indicate that the amyloid precursor protein-derived C-terminal fragments (APP-CTFs) could correspond to an etiological trigger of Alzheimer's disease (AD) pathology. Altered mitochondrial homeostasis is considered an early event in AD development. However, the specific contribution of APP-CTFs to mitochondrial structure, function, and mitophagy defects remains to be established. Here, we demonstrate in neuroblastoma SH-SY5Y cells expressing either APP Swedish mutations, or the β-secretase-derived APP-CTF fragment (C99) combined with β- and γ-secretase inhibition, that APP-CTFs accumulation independently of Aβ triggers excessive mitochondrial morphology alteration (i.e., size alteration and cristae disorganization) associated with enhanced mitochondrial reactive oxygen species production. APP-CTFs accumulation also elicit basal mitophagy failure illustrated by enhanced conversion of LC3, accumulation of LC3-I and/or LC3-II, non-degradation of SQSTM1/p62, inconsistent Parkin and PINK1 recruitment to mitochondria, enhanced levels of membrane and matrix mitochondrial proteins, and deficient fusion of mitochondria with lysosomes. We confirm the contribution of APP-CTFs accumulation to morphological mitochondria alteration and impaired basal mitophagy in vivo in young 3xTgAD transgenic mice treated with γ-secretase inhibitor as well as in adeno-associated-virus-C99 injected mice. Comparison of aged 2xTgAD and 3xTgAD mice indicates that, besides APP-CTFs, an additional contribution of Aβ to late-stage mitophagy activation occurs. Importantly, we report on mitochondrial accumulation of APP-CTFs in human post-mortem sporadic AD brains correlating with mitophagy failure molecular signature. Since defective mitochondria homeostasis plays a pivotal role in AD pathogenesis, targeting mitochondrial dysfunctions and/or mitophagy by counteracting early APP-CTFs accumulation may represent relevant therapeutic interventions in AD.
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Affiliation(s)
- Loan Vaillant-Beuchot
- Institut of Molecular and Cellular Pharmacology, Laboratory of Excellence DistALZ, Université Côte d'Azur, INSERM, CNRS, Sophia-Antipolis, 06560, Valbonne, France
| | - Arnaud Mary
- Institut of Molecular and Cellular Pharmacology, Laboratory of Excellence DistALZ, Université Côte d'Azur, INSERM, CNRS, Sophia-Antipolis, 06560, Valbonne, France
| | - Raphaëlle Pardossi-Piquard
- Institut of Molecular and Cellular Pharmacology, Laboratory of Excellence DistALZ, Université Côte d'Azur, INSERM, CNRS, Sophia-Antipolis, 06560, Valbonne, France
| | - Alexandre Bourgeois
- Institut of Molecular and Cellular Pharmacology, Laboratory of Excellence DistALZ, Université Côte d'Azur, INSERM, CNRS, Sophia-Antipolis, 06560, Valbonne, France
| | - Inger Lauritzen
- Institut of Molecular and Cellular Pharmacology, Laboratory of Excellence DistALZ, Université Côte d'Azur, INSERM, CNRS, Sophia-Antipolis, 06560, Valbonne, France
| | - Fanny Eysert
- Institut of Molecular and Cellular Pharmacology, Laboratory of Excellence DistALZ, Université Côte d'Azur, INSERM, CNRS, Sophia-Antipolis, 06560, Valbonne, France
| | - Paula Fernanda Kinoshita
- Institut of Molecular and Cellular Pharmacology, Laboratory of Excellence DistALZ, Université Côte d'Azur, INSERM, CNRS, Sophia-Antipolis, 06560, Valbonne, France
- Department of Pharmacology, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
| | - Julie Cazareth
- Institut of Molecular and Cellular Pharmacology, Laboratory of Excellence DistALZ, Université Côte d'Azur, INSERM, CNRS, Sophia-Antipolis, 06560, Valbonne, France
| | - Céline Badot
- Institut of Molecular and Cellular Pharmacology, Laboratory of Excellence DistALZ, Université Côte d'Azur, INSERM, CNRS, Sophia-Antipolis, 06560, Valbonne, France
| | | | - Renaud Bussiere
- Institut of Molecular and Cellular Pharmacology, Laboratory of Excellence DistALZ, Université Côte d'Azur, INSERM, CNRS, Sophia-Antipolis, 06560, Valbonne, France
- Department of Medicine, Burlington Danes Building, Hammersmith Hospital Campus, Imperial College London, UK Dementia Research Institute, Du Cane Road, London, W12 0NN, UK
| | - Cécile Martin
- Institut of Molecular and Cellular Pharmacology, Laboratory of Excellence DistALZ, Université Côte d'Azur, INSERM, CNRS, Sophia-Antipolis, 06560, Valbonne, France
| | - Rosanna Mary
- Institut of Molecular and Cellular Pharmacology, Laboratory of Excellence DistALZ, Université Côte d'Azur, INSERM, CNRS, Sophia-Antipolis, 06560, Valbonne, France
| | - Charlotte Bauer
- Institut of Molecular and Cellular Pharmacology, Laboratory of Excellence DistALZ, Université Côte d'Azur, INSERM, CNRS, Sophia-Antipolis, 06560, Valbonne, France
| | - Sophie Pagnotta
- Université Côte d'Azur, Centre Commun de Microscopie Appliquée (CCMA), Parc Valrose, 06108, Nice, France
| | | | - Valérie Buée-Scherrer
- Univ. Lille, Inserm, CHU-Lille, Lille Neuroscience and Cognition, Place de Verdun, 59045, Lille, France
- Inserm UMR-S 1172, Laboratory of Excellence DistALZ, 'Alzheimer and Tauopathies', Bâtiment Biserte, rue Polonovski, 59045, Lille Cedex, France
| | - Luc Buée
- Univ. Lille, Inserm, CHU-Lille, Lille Neuroscience and Cognition, Place de Verdun, 59045, Lille, France
- Inserm UMR-S 1172, Laboratory of Excellence DistALZ, 'Alzheimer and Tauopathies', Bâtiment Biserte, rue Polonovski, 59045, Lille Cedex, France
| | - Sandra Lacas-Gervais
- Université Côte d'Azur, Centre Commun de Microscopie Appliquée (CCMA), Parc Valrose, 06108, Nice, France
| | - Frédéric Checler
- Institut of Molecular and Cellular Pharmacology, Laboratory of Excellence DistALZ, Université Côte d'Azur, INSERM, CNRS, Sophia-Antipolis, 06560, Valbonne, France
| | - Mounia Chami
- Institut of Molecular and Cellular Pharmacology, Laboratory of Excellence DistALZ, Université Côte d'Azur, INSERM, CNRS, Sophia-Antipolis, 06560, Valbonne, France.
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9
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Jayatunga DPW, Hone E, Bharadwaj P, Garg M, Verdile G, Guillemin GJ, Martins RN. Targeting Mitophagy in Alzheimer's Disease. J Alzheimers Dis 2020; 78:1273-1297. [PMID: 33285629 DOI: 10.3233/jad-191258] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Mitochondria perform many essential cellular functions including energy production, calcium homeostasis, transduction of metabolic and stress signals, and mediating cell survival and death. Maintaining viable populations of mitochondria is therefore critical for normal cell function. The selective disposal of damaged mitochondria, by a pathway known as mitophagy, plays a key role in preserving mitochondrial integrity and quality. Mitophagy reduces the formation of reactive oxygen species and is considered as a protective cellular process. Mitochondrial dysfunction and deficits of mitophagy have important roles in aging and especially in neurodegenerative disorders such as Alzheimer's disease (AD). Targeting mitophagy pathways has been suggested to have potential therapeutic effects against AD. In this review, we aim to briefly discuss the emerging concepts on mitophagy, molecular regulation of the mitophagy process, current mitophagy detection methods, and mitophagy dysfunction in AD. Finally, we will also briefly examine the stimulation of mitophagy as an approach for attenuating neurodegeneration in AD.
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Affiliation(s)
- Dona P W Jayatunga
- Centre of Excellence for Alzheimer's Disease Research & Care, School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia
| | - Eugene Hone
- Centre of Excellence for Alzheimer's Disease Research & Care, School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia.,Cooperative Research Centre for Mental Health, Carlton, VIC, Australia
| | - Prashant Bharadwaj
- Centre of Excellence for Alzheimer's Disease Research & Care, School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia.,Cooperative Research Centre for Mental Health, Carlton, VIC, Australia
| | - Manohar Garg
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, University of Newcastle, Callaghan, NSW, Australia.,Riddet Institute, Massey University, Palmerston North, New Zealand
| | - Giuseppe Verdile
- Centre of Excellence for Alzheimer's Disease Research & Care, School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia.,School of Pharmacy and Biomedical Sciences, Faculty of Health Sciences, Curtin Health Innovation Research Institute, Curtin University, Perth, WA, Australia
| | - Gilles J Guillemin
- Department of Pharmacology, School of Medical Sciences, Faculty of Medicine, University of New South Wales, Sydney, NSW, Australia.,St. Vincent's Centre for Applied Medical Research, Sydney, NSW, Australia
| | - Ralph N Martins
- Centre of Excellence for Alzheimer's Disease Research & Care, School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia.,Australian Alzheimer's Research Foundation, Ralph and Patricia Sarich Neuroscience Research Institute, Nedlands, WA, Australia.,Department of Biomedical Sciences, Macquarie University, Sydney, NSW, Australia.,School of Psychiatry and Clinical Neurosciences, University of Western Australia, Perth, WA, Australia.,KaRa Institute of Neurological Diseases, Sydney, NSW, Australia
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10
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Montagnani V, Maresca L, Apollo A, Pepe S, Carr RM, Fernandez-Zapico ME, Stecca B. E3 ubiquitin ligase PARK2, an inhibitor of melanoma cell growth, is repressed by the oncogenic ERK1/2-ELK1 transcriptional axis. J Biol Chem 2020; 295:16058-16071. [PMID: 32938713 DOI: 10.1074/jbc.ra120.014615] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 09/09/2020] [Indexed: 12/26/2022] Open
Abstract
Malignant melanoma, the most aggressive form of skin cancer, is characterized by high prevalence of BRAF/NRAS mutations and hyperactivation of extracellular signal-regulated kinase 1 and 2 (ERK1/2), mitogen-activated protein kinases (MAPK), leading to uncontrolled melanoma growth. Efficacy of current targeted therapies against mutant BRAF or MEK1/2 have been hindered by existence of innate or development of acquired resistance. Therefore, a better understanding of the mechanisms controlled by MAPK pathway driving melanogenesis will help develop new treatment approaches targeting this oncogenic cascade. Here, we identify E3 ubiquitin ligase PARK2 as a direct target of ELK1, a known transcriptional effector of MAPK signaling in melanoma cells. We show that pharmacological inhibition of BRAF-V600E or ERK1/2 in melanoma cells increases PARK2 expression. PARK2 overexpression reduces melanoma cell growth in vitro and in vivo and induces apoptosis. Conversely, its genetic silencing increases melanoma cell proliferation and reduces cell death. Further, we demonstrate that ELK1 is required by the BRAF-ERK1/2 pathway to repress PARK2 expression and promoter activity in melanoma cells. Clinically, PARK2 is highly expressed in WT BRAF and NRAS melanomas, but it is expressed at low levels in melanomas carrying BRAF/NRAS mutations. Overall, our data provide new insights into the tumor suppressive role of PARK2 in malignant melanoma and uncover a novel mechanism for the negative regulation of PARK2 via the ERK1/2-ELK1 axis. These findings suggest that reactivation of PARK2 may be a promising therapeutic approach to counteract melanoma growth.
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Affiliation(s)
- Valentina Montagnani
- Core Research Laboratory, Institute for Cancer Research, Prevention and Clinical Network (ISPRO), Florence, Italy
| | - Luisa Maresca
- Core Research Laboratory, Institute for Cancer Research, Prevention and Clinical Network (ISPRO), Florence, Italy
| | - Alessandro Apollo
- Core Research Laboratory, Institute for Cancer Research, Prevention and Clinical Network (ISPRO), Florence, Italy
| | - Sara Pepe
- Core Research Laboratory, Institute for Cancer Research, Prevention and Clinical Network (ISPRO), Florence, Italy; Department of Medical Biotechnologies, University of Siena, Siena, Italy
| | - Ryan M Carr
- Division of Oncology Research, Department of Oncology, Schulze Center for Novel Therapeutics, Mayo Clinic, Rochester, Minnesota USA
| | - Martin E Fernandez-Zapico
- Division of Oncology Research, Department of Oncology, Schulze Center for Novel Therapeutics, Mayo Clinic, Rochester, Minnesota USA
| | - Barbara Stecca
- Core Research Laboratory, Institute for Cancer Research, Prevention and Clinical Network (ISPRO), Florence, Italy.
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11
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Liu X, Hebron M, Shi W, Lonskaya I, Moussa CEH. Ubiquitin specific protease-13 independently regulates parkin ubiquitination and alpha-synuclein clearance in alpha-synucleinopathies. Hum Mol Genet 2019; 28:548-560. [PMID: 30329047 DOI: 10.1093/hmg/ddy365] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Accepted: 10/09/2018] [Indexed: 12/22/2022] Open
Abstract
Ubiquitin specific proteases (USPs) are de-ubiquitinases (DUBs) that control protein ubiquitination cycle. The role of DUBs is poorly understood in neurodegenerative diseases. We found that USP13 is overexpressed in post-mortem Parkinson's disease (PD) brains. We investigated whether changes in USP13 levels can affect two molecules, parkin and alpha-synuclein, that are implicated in PD pathogenesis. Parkin is an E3 ubiquitin ligase that is regulated by ubiquitination and targets certain proteins for degradation, and alpha-synuclein may be ubiquitinated and recycled in the normal brain. We found that USP13 independently regulates parkin and alpha-synuclein ubiquitination in models of alpha-synucleinopathies. USP13 shRNA knockdown increases alpha-synuclein ubiquitination and clearance, in a parkin-independent manner. Furthermore, USP13 overexpression counteracts the effects of a tyrosine kinase inhibitor, Nilotinib, while USP13 knockdown facilitates Nilotinib effects on alpha-synculein clearance, suggesting that alpha-synuclein ubiquitnation is important for its clearance. These studies provide novel evidence of USP13 effects on parkin and alpha-synuclein metabolism and suggest that USP13 is a potential therapeutic target in the alpha-synucleinopathies.
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Affiliation(s)
- Xiaoguang Liu
- Department of Neurology, Laboratory for Dementia and Parkinsonism, Translational Neurotherapeutics Program, National Parkinson's Foundation Center of Excellence, Lewy Body Dementia Research Center of Excellence, Georgetown University Medical Center, N.W. Washington D.C., USA
| | - Michaeline Hebron
- Department of Neurology, Laboratory for Dementia and Parkinsonism, Translational Neurotherapeutics Program, National Parkinson's Foundation Center of Excellence, Lewy Body Dementia Research Center of Excellence, Georgetown University Medical Center, N.W. Washington D.C., USA
| | - Wangke Shi
- Department of Neurology, Laboratory for Dementia and Parkinsonism, Translational Neurotherapeutics Program, National Parkinson's Foundation Center of Excellence, Lewy Body Dementia Research Center of Excellence, Georgetown University Medical Center, N.W. Washington D.C., USA
| | - Irina Lonskaya
- Department of Neurology, Laboratory for Dementia and Parkinsonism, Translational Neurotherapeutics Program, National Parkinson's Foundation Center of Excellence, Lewy Body Dementia Research Center of Excellence, Georgetown University Medical Center, N.W. Washington D.C., USA
| | - Charbel E-H Moussa
- Department of Neurology, Laboratory for Dementia and Parkinsonism, Translational Neurotherapeutics Program, National Parkinson's Foundation Center of Excellence, Lewy Body Dementia Research Center of Excellence, Georgetown University Medical Center, N.W. Washington D.C., USA
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12
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Kumar D, Kumar P. Integrated Mechanism of Lysine 351, PARK2, and STUB1 in AβPP Ubiquitination. J Alzheimers Dis 2019; 68:1125-1150. [DOI: 10.3233/jad-181219] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Dhiraj Kumar
- Molecular Neuroscience and Functional Genomics Laboratory, Delhi Technological University (Formerly DCE), Delhi, India
| | - Pravir Kumar
- Molecular Neuroscience and Functional Genomics Laboratory, Delhi Technological University (Formerly DCE), Delhi, India
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13
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Wei CJ, Cui P, Li H, Lang WJ, Liu GY, Ma XF. Shared genes between Alzheimer's disease and ischemic stroke. CNS Neurosci Ther 2019; 25:855-864. [PMID: 30859738 PMCID: PMC6630005 DOI: 10.1111/cns.13117] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2018] [Revised: 02/12/2019] [Accepted: 02/13/2019] [Indexed: 02/06/2023] Open
Abstract
Aims Although converging evidence from experimental and epidemiological studies indicates Alzheimer's disease (AD) and ischemic stroke (IS) are related, the genetic basis underlying their links is less well characterized. Traditional SNP‐based genome‐wide association studies (GWAS) have failed to uncover shared susceptibility variants of AD and IS. Therefore, this study was designed to investigate whether pleiotropic genes existed between AD and IS to account for their phenotypic association, although this was not reported in previous studies. Methods Taking advantage of large‐scale GWAS summary statistics of AD (17,008 AD cases and 37,154 controls) and IS (10,307 IS cases and 19,326 controls), we performed gene‐based analysis implemented in VEGAS2 and Fisher's meta‐analysis of the set of overlapped genes of nominal significance in both diseases. Subsequently, gene expression analysis in AD‐ or IS‐associated expression datasets was conducted to explore the transcriptional alterations of pleiotropic genes identified. Results 16 AD‐IS pleiotropic genes surpassed the cutoff for Bonferroni‐corrected significance. Notably, MS4A4A and TREM2, two established AD‐susceptibility genes showed remarkable alterations in the spleens and brains afflicted by IS, respectively. Among the prioritized genes identified by virtue of literature‐based knowledge, most are immune‐relevant genes (EPHA1, MS4A4A, UBE2L3 and TREM2), implicating crucial roles of the immune system in the pathogenesis of AD and IS. Conclusions The observation that AD and IS had shared disease‐associated genes offered mechanistic insights into their common pathogenesis, predominantly involving the immune system. More importantly, our findings have important implications for future research directions, which are encouraged to verify the involvement of these candidates in AD and IS and interpret the exact molecular mechanisms of action.
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Affiliation(s)
- Chang-Juan Wei
- Department of Neurology, Tianjin Medical University General Hospital, Tianjin, China.,Tianjin Neurological Institute, Key Laboratory of Post-neurotrauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education, Tianjin, China
| | - Pan Cui
- Department of Neurology, Tianjin Medical University General Hospital, Tianjin, China.,Tianjin Neurological Institute, Key Laboratory of Post-neurotrauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education, Tianjin, China
| | - He Li
- Department of Neurology, Tianjin Medical University General Hospital, Tianjin, China.,Tianjin Neurological Institute, Key Laboratory of Post-neurotrauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education, Tianjin, China
| | - Wen-Jing Lang
- Department of Neurology, Tianjin Medical University General Hospital, Tianjin, China.,Tianjin Neurological Institute, Key Laboratory of Post-neurotrauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education, Tianjin, China
| | - Gui-You Liu
- School of Life Science and Technology, Harbin Institute of Technology, Harbin, China
| | - Xiao-Feng Ma
- Department of Neurology, Tianjin Medical University General Hospital, Tianjin, China.,Tianjin Neurological Institute, Key Laboratory of Post-neurotrauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education, Tianjin, China
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14
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Komura H, Kakio S, Sasahara T, Arai Y, Takino N, Sato M, Satomura K, Ohnishi T, Nabeshima YI, Muramatsu SI, Kii I, Hoshi M. Alzheimer Aβ Assemblies Accumulate in Excitatory Neurons upon Proteasome Inhibition and Kill Nearby NAKα3 Neurons by Secretion. iScience 2019; 13:452-477. [PMID: 30827871 PMCID: PMC6443839 DOI: 10.1016/j.isci.2019.01.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 11/14/2018] [Accepted: 01/11/2019] [Indexed: 12/11/2022] Open
Abstract
We identified ∼30-mer amyloid-β protein (Aβ) assemblies, termed amylospheroids, from brains of patients with Alzheimer disease (AD) as toxic entities responsible for neurodegeneration and showed that Na+,K+-ATPase α3 (NAKα3) is the sole target of amylospheroid-mediated neurodegeneration. However, it remains unclear where in neurons amylospheroids form and how they reach their targets to induce neurodegeneration. Here, we present an in vitro culture system designed to chronologically follow amylospheroid formation in mature neurons expressing amyloid precursor protein bearing early-onset AD mutations. Amylospheroids were found to accumulate mainly in the trans-Golgi network of excitatory neurons and were initially transported in axons. Proteasome inhibition dramatically increased amylospheroid amounts in trans-Golgi by increasing Aβ levels and induced dendritic transport. Amylospheroids were secreted and caused the degeneration of adjacent NAKα3-expressing neurons. Interestingly, the ASPD-producing neurons later died non-apoptotically. Our findings demonstrate a link between ASPD levels and proteasome function, which may have important implications for AD pathophysiology.
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Affiliation(s)
- Hitomi Komura
- Department of Brain and Neurodegenerative Disease Research, Institute of Biomedical Research and Innovation, Foundation for Biomedical Research and Innovation at Kobe, Kobe 650-0047, Japan; TAO Health Life Pharma Co., Ltd., Med-Pharma Collaboration Bldg, Kyoto University, 46-29 Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Shota Kakio
- Department of Brain and Neurodegenerative Disease Research, Institute of Biomedical Research and Innovation, Foundation for Biomedical Research and Innovation at Kobe, Kobe 650-0047, Japan; TAO Health Life Pharma Co., Ltd., Med-Pharma Collaboration Bldg, Kyoto University, 46-29 Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Tomoya Sasahara
- Department of Brain and Neurodegenerative Disease Research, Institute of Biomedical Research and Innovation, Foundation for Biomedical Research and Innovation at Kobe, Kobe 650-0047, Japan; TAO Health Life Pharma Co., Ltd., Med-Pharma Collaboration Bldg, Kyoto University, 46-29 Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Yoshie Arai
- Department of Brain and Neurodegenerative Disease Research, Institute of Biomedical Research and Innovation, Foundation for Biomedical Research and Innovation at Kobe, Kobe 650-0047, Japan; TAO Health Life Pharma Co., Ltd., Med-Pharma Collaboration Bldg, Kyoto University, 46-29 Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Naomi Takino
- Division of Neurology, Jichi Medical University, Shimotsuke 329-0498, Japan
| | - Michio Sato
- Meiji University, Graduate School of Agriculture, Meiji University, Kawasaki 214-8571, Japan
| | - Kaori Satomura
- Department of Brain and Neurodegenerative Disease Research, Institute of Biomedical Research and Innovation, Foundation for Biomedical Research and Innovation at Kobe, Kobe 650-0047, Japan; TAO Health Life Pharma Co., Ltd., Med-Pharma Collaboration Bldg, Kyoto University, 46-29 Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Takayuki Ohnishi
- Department of Brain and Neurodegenerative Disease Research, Institute of Biomedical Research and Innovation, Foundation for Biomedical Research and Innovation at Kobe, Kobe 650-0047, Japan; TAO Health Life Pharma Co., Ltd., Med-Pharma Collaboration Bldg, Kyoto University, 46-29 Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Yo-Ichi Nabeshima
- Department of Gerontology, Institute of Biomedical Research and Innovation, Foundation for Biomedical Research and Innovation at Kobe, Kobe 650-0047, Japan
| | - Shin-Ichi Muramatsu
- Division of Neurology, Jichi Medical University, Shimotsuke 329-0498, Japan; Center for Gene & Cell Therapy, The Institute of Medical Science, University of Tokyo, Tokyo 108-0071, Japan
| | - Isao Kii
- RIKEN Center for Life Science Technologies, Division of Bio-Function Dynamics Imaging, Kobe 650-0047, Japan
| | - Minako Hoshi
- Department of Anatomy and Developmental Biology, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan.
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15
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Genetic activation of parkin rescues TAF15-induced neurotoxicity in a Drosophila model of amyotrophic lateral sclerosis. Neurobiol Aging 2019; 73:68-73. [DOI: 10.1016/j.neurobiolaging.2018.09.023] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 08/09/2018] [Accepted: 09/14/2018] [Indexed: 12/14/2022]
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16
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Briston T, Hicks AR. Mitochondrial dysfunction and neurodegenerative proteinopathies: mechanisms and prospects for therapeutic intervention. Biochem Soc Trans 2018; 46:829-842. [PMID: 29986938 PMCID: PMC6103456 DOI: 10.1042/bst20180025] [Citation(s) in RCA: 78] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 05/10/2018] [Accepted: 05/21/2018] [Indexed: 12/22/2022]
Abstract
Neurodegenerative proteinopathies are a group of pathologically similar, progressive disorders of the nervous system, characterised by structural alterations within and toxic misfolding of susceptible proteins. Oligomerisation of Aβ, tau, α-synuclein and TDP-43 leads to a toxin gain- or loss-of-function contributing to the phenotype observed in Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis and frontotemporal dementia. Misfolded proteins can adversely affect mitochondria, and post-mitotic neurones are especially sensitive to metabolic dysfunction. Misfolded proteins impair mitochondrial dynamics (morphology and trafficking), preventing functional mitochondria reaching the synapse, the primary site of ATP utilisation. Furthermore, a direct association of misfolded proteins with mitochondria may precipitate or augment dysfunctional oxidative phosphorylation and mitochondrial quality control, causing redox dyshomeostasis observed in disease. As such, a significant interest lies in understanding mechanisms of mitochondrial toxicity in neurodegenerative disorders and in dissecting these mechanisms with a view of maintaining mitochondrial homeostasis in disease. Recent advances in understanding mitochondrially controlled cell death pathways and elucidating the mitochondrial permeability pore bioarchitecture are beginning to present new avenues to target neurodegeneration. Novel mitochondrial roles of deubiquitinating enzymes are coming to light and present an opportunity for a new class of proteins to target therapeutically with the aim of promoting mitophagy and the ubiquitin-proteasome system. The brain is enormously metabolically active, placing a large emphasis on maintaining ATP supply. Therefore, identifying mechanisms to sustain mitochondrial function may represent a common intervention point across all proteinopathies.
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Affiliation(s)
- Thomas Briston
- Neurology Innovation Centre, Hatfield Research Laboratories, Eisai Ltd, Hatfield, U.K.
| | - Amy R Hicks
- Neurology Innovation Centre, Hatfield Research Laboratories, Eisai Ltd, Hatfield, U.K
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17
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Tau clearance improves astrocytic function and brain glutamate-glutamine cycle. J Neurol Sci 2018; 391:90-99. [PMID: 30103978 DOI: 10.1016/j.jns.2018.06.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Revised: 06/07/2018] [Accepted: 06/12/2018] [Indexed: 02/01/2023]
Abstract
Tau hyperphosphorylation is a critical factor in neurodegenerative diseases, including dementia and Parkinsonism. Existing animal models of tauopathies express tau in neurons within the forebrain and do not often show tau accumulation in the brainstem and astrocytes. This study aims to understand the effects of differential regional expression of tau on neurotransmitter balance in the brain. To obtain an animal model that expresses tau in the brainstem, we bred hemizygous mice that express P301L tau (TauP301L) and detected hyper-phosphorylated tau (p-tau) predominantly in the hippocampus, cortex, brainstem and thalamus. We previously demonstrated that TauP301L mice [26] express tau under the control of a prion promoter in both neurons and astrocytes, reminiscent of human tauopathies. We treated TauP301L mice with tyrosine kinase inhibitors (TKIs) to determine the effects of tau clearance on neurotransmitter balance and astrocytic function. 13C/1H MRS reveals astrocytic dysfunction via reduced glial aspartate and impaired glutamate-glutamine cycle. An increase in glutamate and GABA and decrease in glutamine were observed in homozygous mice compared to hemizygous and control littermates. Daily treatment with TKIs, nilotinib or bosutinib led to p-tau clearance via autophagy and reversal of neurotransmitter imbalance. These data suggest that accumulation of p-tau in the brainstem does not alter dopamine metabolism but may trigger glutamate toxicity and astrocytic dysfunction in the TauP301L mouse. TKIs reverse tau effects via reversal of neurotransmitter imbalance.
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18
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Sassone J, Serratto G, Valtorta F, Silani V, Passafaro M, Ciammola A. The synaptic function of parkin. Brain 2017; 140:2265-2272. [PMID: 28335015 DOI: 10.1093/brain/awx006] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Accepted: 12/05/2016] [Indexed: 12/11/2022] Open
Abstract
Loss of function mutations in the gene PARK2, which encodes the protein parkin, cause autosomal recessive juvenile parkinsonism, a neurodegenerative disease characterized by degeneration of the dopaminergic neurons localized in the substantia nigra pars compacta. No therapy is effective in slowing disease progression mostly because the pathogenesis of the disease is yet to be understood. From accruing evidence suggesting that the protein parkin directly regulates synapses it can be hypothesized that PARK2 gene mutations lead to early synaptic damage that results in dopaminergic neuron loss over time. We review evidence that supports the role of parkin in modulating excitatory and dopaminergic synapse functions. We also discuss how these findings underpin the concept that autosomal recessive juvenile parkinsonism can be primarily a synaptopathy. Investigation into the molecular interactions between parkin and synaptic proteins may yield novel targets for pharmacologic interventions.
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Affiliation(s)
- Jenny Sassone
- San Raffaele Scientific Institute and Vita-Salute University, Milan, Italy
| | - GiuliaMaia Serratto
- CNR Institute of Neuroscience, Department BIOMETRA, Università degli Studi di Milano, Milan, Italy.,IRCCS Istituto Auxologico Italiano, Department of Neurology and Laboratory of Neuroscience, Milan, Italy
| | - Flavia Valtorta
- San Raffaele Scientific Institute and Vita-Salute University, Milan, Italy
| | - Vincenzo Silani
- IRCCS Istituto Auxologico Italiano, Department of Neurology and Laboratory of Neuroscience, Milan, Italy.,Department of Pathophysiology and Transplantation, 'Dino Ferrari' Centre, Università degli Studi di Milano, Milan, Italy
| | - Maria Passafaro
- CNR Institute of Neuroscience, Department BIOMETRA, Università degli Studi di Milano, Milan, Italy
| | - Andrea Ciammola
- IRCCS Istituto Auxologico Italiano, Department of Neurology and Laboratory of Neuroscience, Milan, Italy
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19
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Chen Y, Deng J, Wang P, Yang M, Chen X, Zhu L, Liu J, Lu B, Shen Y, Fushimi K, Xu Q, Wu JY. PINK1 and Parkin are genetic modifiers for FUS-induced neurodegeneration. Hum Mol Genet 2017; 25:5059-5068. [PMID: 27794540 DOI: 10.1093/hmg/ddw310] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 09/02/2016] [Indexed: 12/13/2022] Open
Abstract
Dysregulation of Fused in Sarcoma (FUS) gene expression is associated with fronto-temporal lobar degeneration (FTLD), and missense mutations in the FUS gene have been identified in patients affected by amyotrophic lateral sclerosis (ALS). However, molecular and cellular defects underlying FUS proteinopathy remain to be elucidated. Here, we examined whether genes important for mitochondrial quality control play a role in FUS proteinopathy. In our genetic screening, Pink1 and Park genes were identified as modifiers of neurodegeneration phenotypes induced by wild type (Wt) or ALS-associated P525L-mutant human FUS. Down-regulating expression of either Pink1 or Parkin genes ameliorated FUS-induced neurodegeneration phenotypes. The protein levels of PINK1 and Parkin were elevated in cells overexpressing FUS. Remarkably, ubiquitinylation of Miro1 protein, a downstream target of the E3 ligase activity of Parkin, was also increased in cells overexpressing FUS protein. In fly motor neurons expressing FUS, both motility and processivity of mitochondrial axonal transport were reduced by expression of either Wt- or P525L-mutant FUS. Finally, down-regulating PINK1 or Parkin partially rescued the locomotive defects and enhanced the survival rate in transgenic flies expressing FUS. Our data indicate that PINK1 and Parkin play an important role in FUS-induced neurodegeneration. This study has uncovered a previously unknown link between FUS proteinopathy and PINK1/Parkin genes, providing new insights into the pathogenesis of FUS proteinopathy.
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Affiliation(s)
- Yanbo Chen
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Science, Beijing, China.,Department of Neurology, Center for Genetic Medicine, Lurie Cancer Center, Northwestern University Feinberg School of Medicine, 303 E. Superior, Chicago, IL, USA.,National Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences & Neuroscience Center, Chinese Academy of Medical Sciences, Beijing, China
| | - Jianwen Deng
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Science, Beijing, China
| | - Peng Wang
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Science, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Mengxue Yang
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Science, Beijing, China.,Department of Neurology, Center for Genetic Medicine, Lurie Cancer Center, Northwestern University Feinberg School of Medicine, 303 E. Superior, Chicago, IL, USA
| | - Xiaoping Chen
- Department of Neurology, Center for Genetic Medicine, Lurie Cancer Center, Northwestern University Feinberg School of Medicine, 303 E. Superior, Chicago, IL, USA
| | - Li Zhu
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Science, Beijing, China
| | - Jianghong Liu
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Science, Beijing, China
| | - Bingwei Lu
- Department of Pathology, Stanford University, School of Medicine, Stanford, CA, USA
| | - Yan Shen
- National Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences & Neuroscience Center, Chinese Academy of Medical Sciences, Beijing, China
| | - Kazuo Fushimi
- Department of Neurology, Center for Genetic Medicine, Lurie Cancer Center, Northwestern University Feinberg School of Medicine, 303 E. Superior, Chicago, IL, USA
| | - Qi Xu
- National Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences & Neuroscience Center, Chinese Academy of Medical Sciences, Beijing, China
| | - Jane Y Wu
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Science, Beijing, China.,Department of Neurology, Center for Genetic Medicine, Lurie Cancer Center, Northwestern University Feinberg School of Medicine, 303 E. Superior, Chicago, IL, USA
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20
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Khan SH, Zhao D, Shah SZA, Hassan MF, Zhu T, Song Z, Zhou X, Yang L. Parkin Overexpression Ameliorates PrP106-126-Induced Neurotoxicity via Enhanced Autophagy in N2a Cells. Cell Mol Neurobiol 2017; 37:717-728. [PMID: 27430567 DOI: 10.1007/s10571-016-0407-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 07/12/2016] [Indexed: 10/21/2022]
Abstract
Transmissible spongiform encephalopathies (TSEs) are caused by the accumulation of the abnormal prion protein scrapie (PrPSc). Prion protein aggregation, misfolding, and cytotoxicity in the brain are the major causes of neuronal dysfunction and ultimate neurodegeneration in all TSEs. Parkin, an E3 ubiquitin ligase, has been studied extensively in all major protein misfolding aggregating diseases, especially Parkinson's disease and Alzheimer's disease, but the role of parkin in TSEs remains unknown. Here we investigated the role of parkin in a prion disease cell model in which neuroblastoma2a (N2a) cells were treated with prion peptide PrP106-126. We observed a gradual decrease in the soluble parkin level upon treatment with PrP106-126 in a time-dependent manner. Furthermore, endogenous parkin colocalized with FITC-tagged prion fragment106-126. Overexpression of parkin in N2a cells via transfection repressed apoptosis by enhancing autophagy. Parkin-overexpressing cells also showed reductions in apoptotic BAX translocation to the mitochondria and cytochrome c release to the cytosol, which ultimately inhibited activation of proapoptotic caspases. Taken together, our findings reveal a parkin-mediated cytoprotective mechanism against PrP106-126 toxicity, which is a novel potential therapeutic target for treating prion diseases.
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Affiliation(s)
- Sher Hayat Khan
- National Animal Transmissible Spongiform Encephalopathy Laboratory, Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine and State Key Laboratory of Agrobiotechnology, China Agricultural University, Beijing, China
| | - Deming Zhao
- National Animal Transmissible Spongiform Encephalopathy Laboratory, Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine and State Key Laboratory of Agrobiotechnology, China Agricultural University, Beijing, China
| | - Syed Zahid Ali Shah
- National Animal Transmissible Spongiform Encephalopathy Laboratory, Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine and State Key Laboratory of Agrobiotechnology, China Agricultural University, Beijing, China
| | - Mohammad Farooque Hassan
- National Animal Transmissible Spongiform Encephalopathy Laboratory, Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine and State Key Laboratory of Agrobiotechnology, China Agricultural University, Beijing, China
| | - Ting Zhu
- Fujian Agriculture and Forestry University, Fuzhou, China
| | - Zhiqi Song
- National Animal Transmissible Spongiform Encephalopathy Laboratory, Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine and State Key Laboratory of Agrobiotechnology, China Agricultural University, Beijing, China
| | - Xiangmei Zhou
- National Animal Transmissible Spongiform Encephalopathy Laboratory, Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine and State Key Laboratory of Agrobiotechnology, China Agricultural University, Beijing, China
| | - Lifeng Yang
- National Animal Transmissible Spongiform Encephalopathy Laboratory, Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, College of Veterinary Medicine and State Key Laboratory of Agrobiotechnology, China Agricultural University, Beijing, China.
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21
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Gupta A, Anjomani-Virmouni S, Koundouros N, Dimitriadi M, Choo-Wing R, Valle A, Zheng Y, Chiu YH, Agnihotri S, Zadeh G, Asara JM, Anastasiou D, Arends MJ, Cantley LC, Poulogiannis G. PARK2 Depletion Connects Energy and Oxidative Stress to PI3K/Akt Activation via PTEN S-Nitrosylation. Mol Cell 2017; 65:999-1013.e7. [PMID: 28306514 PMCID: PMC5426642 DOI: 10.1016/j.molcel.2017.02.019] [Citation(s) in RCA: 95] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Revised: 12/13/2016] [Accepted: 02/17/2017] [Indexed: 11/23/2022]
Abstract
PARK2 is a gene implicated in disease states with opposing responses in cell fate determination, yet its contribution in pro-survival signaling is largely unknown. Here we show that PARK2 is altered in over a third of all human cancers, and its depletion results in enhanced phosphatidylinositol 3-kinase/Akt (PI3K/Akt) activation and increased vulnerability to PI3K/Akt/mTOR inhibitors. PARK2 depletion contributes to AMPK-mediated activation of endothelial nitric oxide synthase (eNOS), enhanced levels of reactive oxygen species, and a concomitant increase in oxidized nitric oxide levels, thereby promoting the inhibition of PTEN by S-nitrosylation and ubiquitination. Notably, AMPK activation alone is sufficient to induce PTEN S-nitrosylation in the absence of PARK2 depletion. Park2 loss and Pten loss also display striking cooperativity to promote tumorigenesis in vivo. Together, our findings reveal an important missing mechanism that might account for PTEN suppression in PARK2-deficient tumors, and they highlight the importance of PTEN S-nitrosylation in supporting cell survival and proliferation under conditions of energy deprivation.
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Affiliation(s)
- Amit Gupta
- Signalling and Cancer Metabolism Team, Division of Cancer Biology, The Institute of Cancer Research, 237 Fulham Road, London SW3 6JB, UK
| | - Sara Anjomani-Virmouni
- Signalling and Cancer Metabolism Team, Division of Cancer Biology, The Institute of Cancer Research, 237 Fulham Road, London SW3 6JB, UK
| | - Nikos Koundouros
- Signalling and Cancer Metabolism Team, Division of Cancer Biology, The Institute of Cancer Research, 237 Fulham Road, London SW3 6JB, UK; Division of Computational and Systems Medicine, Department of Surgery and Cancer, Imperial College London, London SW7 2AZ, UK
| | - Maria Dimitriadi
- Signalling and Cancer Metabolism Team, Division of Cancer Biology, The Institute of Cancer Research, 237 Fulham Road, London SW3 6JB, UK; Department of Biological and Environmental Sciences, University of Hertfordshire, Hatfield AL10 9AB, UK
| | - Rayman Choo-Wing
- Novartis Institutes for BioMedical Research, Inc., 181 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Adamo Valle
- Signalling and Cancer Metabolism Team, Division of Cancer Biology, The Institute of Cancer Research, 237 Fulham Road, London SW3 6JB, UK; Energy Metabolism and Nutrition, University of Balearic Islands, Research Institute of Health Sciences (IUNICS) and Medical Research Institute of Palma (IdISPa), 07122 Palma de Mallorca, Spain; Biomedical Research Networking Center for Physiopathology of Obesity and Nutrition (CIBERobn), Instituto de Salud Carlos III, 28029 Madrid, Spain
| | - Yuxiang Zheng
- Meyer Cancer Center, Department of Medicine, Weill Cornell Medicine, New York, NY 10065, USA
| | - Yu-Hsin Chiu
- Novartis Institutes for BioMedical Research, Inc., 22 Windsor Street, Cambridge, MA 02139, USA
| | - Sameer Agnihotri
- MacFeeters-Hamilton Neurooncology Program, Princess Margaret Cancer Centre, Toronto, ON M5G 2M9, Canada
| | - Gelareh Zadeh
- MacFeeters-Hamilton Neurooncology Program, Princess Margaret Cancer Centre, Toronto, ON M5G 2M9, Canada
| | - John M Asara
- Division of Signal Transduction, Beth Israel Deaconess Medical Center, Boston, MA 02115, USA; Department of Medicine, Harvard Medical School, Boston, MA 02175, USA
| | | | - Mark J Arends
- University of Edinburgh, Division of Pathology, Edinburgh Cancer Research Centre, Institute of Genetics & Molecular Medicine, Western General Hospital, Edinburgh EH4 2XR, UK
| | - Lewis C Cantley
- Meyer Cancer Center, Department of Medicine, Weill Cornell Medicine, New York, NY 10065, USA.
| | - George Poulogiannis
- Signalling and Cancer Metabolism Team, Division of Cancer Biology, The Institute of Cancer Research, 237 Fulham Road, London SW3 6JB, UK; Division of Computational and Systems Medicine, Department of Surgery and Cancer, Imperial College London, London SW7 2AZ, UK.
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22
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Bhowmick DC, Singh S, Trikha S, Jeremic AM. The Molecular Physiopathogenesis of Islet Amyloidosis. Handb Exp Pharmacol 2017; 245:271-312. [PMID: 29043504 DOI: 10.1007/164_2017_62] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Human islet amyloid polypeptide or amylin (hA) is a 37-amino acid peptide hormone produced and co-secreted with insulin by pancreatic β-cells. Under physiological conditions, hA regulates a broad range of biological processes including insulin release and slowing of gastric emptying, thereby maintaining glucose homeostasis. However, under the pathological conditions associated with type 2 diabetes mellitus (T2DM), hA undergoes a conformational transition from soluble random coil monomers to alpha-helical oligomers and insoluble β-sheet amyloid fibrils or amyloid plaques. There is a positive correlation between hA oligomerization/aggregation, hA toxicity, and diabetes progression. Because the homeostatic balance between hA synthesis, release, and uptake is lost in diabetics and hA aggregation is a hallmark of T2DM, this chapter focuses on the biophysical and cell biology studies investigating molecular mechanisms of hA uptake, trafficking, and degradation in pancreatic cells and its relevance to h's toxicity. We will also discuss the regulatory role of endocytosis and proteolytic pathways in clearance of toxic hA species. Finally, we will discuss potential pharmacological approaches for specific targeting of hA trafficking pathways and toxicity in islet β-cells as potential new avenues toward treatments of T2DM patients.
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Affiliation(s)
| | - Sanghamitra Singh
- Department of Biological Sciences, The George Washington University, Washington, DC, 20052, USA
| | - Saurabh Trikha
- Department of Biological Sciences, The George Washington University, Washington, DC, 20052, USA
| | - Aleksandar M Jeremic
- Department of Biological Sciences, The George Washington University, Washington, DC, 20052, USA.
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Alzheimer disease: modeling an Aβ-centered biological network. Mol Psychiatry 2016; 21:861-71. [PMID: 27021818 DOI: 10.1038/mp.2016.38] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Revised: 02/16/2016] [Accepted: 02/18/2016] [Indexed: 01/15/2023]
Abstract
In genetically complex diseases, the search for missing heritability is focusing on rare variants with large effect. Thanks to next generation sequencing technologies, genome-wide characterization of these variants is now feasible in every individual. However, a lesson from current studies is that collapsing rare variants at the gene level is often insufficient to obtain a statistically significant signal in case-control studies, and that network-based analyses are an attractive complement to classical approaches. In Alzheimer disease (AD), according to the prevalent amyloid cascade hypothesis, the pathology is driven by the amyloid beta (Aβ) peptide. In past years, based on experimental studies, several hundreds of proteins have been shown to interfere with Aβ production, clearance, aggregation or toxicity. Thanks to a manual curation of the literature, we identified 335 genes/proteins involved in this biological network and classified them according to their cellular function. The complete list of genes, or its subcomponents, will be of interest in ongoing AD genetic studies.
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Klimczak PF, Ventury DH, Faucz FR, Settas N, Machado de Souza C, Sotomaior VS. Association of a PARK2 Germline Variant and Epithelial Ovarian Cancer in a Southern Brazilian Population. Oncology 2016; 91:101-5. [PMID: 27286703 DOI: 10.1159/000446657] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 04/28/2016] [Indexed: 01/14/2023]
Abstract
Ovarian cancer (OC) is the eighth most common cancer among women in Brazil and seventh in the world population. OC has a high mortality rate and is difficult to diagnose. Currently, OC detection most often occurs at an advanced stage of the disease due to its silent progression, which contributes to the high mortality rate. Available genetic markers are not considered specifically enough for an initial and definite diagnosis. The association with new genes involved with OC can provide a better understanding of this pathology as well as contribute to the development of a marker scenario, providing an improvement in the treatment and survival of patients. The aim of this study was to examine the potential association between the PARK2 gene and epithelial ovarian cancer (EOC). Accordingly, we conducted a study for which 25 patients and 87 controls were recruited. Linkage disequilibrium analysis showed that the four studied tag SNPs (rs2803073, rs6930532, rs1040079, and rs2276201) were independent. Our results using the multivariate analysis between the additive and dominant model demonstrated that tag SNP rs2803073 of PARK2 is associated with susceptibility to EOC (p = 0.018, OR = 0.42). These findings suggest that hereditary variation in the PARK2 gene could influence EOC development mechanisms.
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Affiliation(s)
- Phamela Ferreira Klimczak
- Graduate Program in Health Sciences, School of Medicine, Pontifx00ED;cia Universidade Catx00F3;lica do Paranx00E1; (PUCPR), Curitiba, Brazil
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Zhang CW, Hang L, Yao TP, Lim KL. Parkin Regulation and Neurodegenerative Disorders. Front Aging Neurosci 2016; 7:248. [PMID: 26793099 PMCID: PMC4709595 DOI: 10.3389/fnagi.2015.00248] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Accepted: 12/17/2015] [Indexed: 12/13/2022] Open
Abstract
Parkin is a unique, multifunctional ubiquitin ligase whose various roles in the cell, particularly in neurons, are widely thought to be protective. The pivotal role that Parkin plays in maintaining neuronal survival is underscored by our current recognition that Parkin dysfunction represents not only a predominant cause of familial parkinsonism but also a formal risk factor for the more common, sporadic form of Parkinson’s disease (PD). Accordingly, keen research on Parkin over the past decade has led to an explosion of knowledge regarding its physiological roles and its relevance to PD. However, our understanding of Parkin is far from being complete. Indeed, surprises emerge from time to time that compel us to constantly update the paradigm of Parkin function. For example, we now know that Parkin’s function is not confined to mere housekeeping protein quality control (QC) roles but also includes mitochondrial homeostasis and stress-related signaling. Furthermore, emerging evidence also suggest a role for Parkin in several other major neurodegenerative diseases including Alzheimer’s disease (AD) and Amyotrophic Lateral Sclerosis (ALS). Yet, it remains truly amazing to note that a single enzyme could serve such multitude of functions and cellular roles. Clearly, its activity has to be tightly regulated. In this review, we shall discuss this and how dysregulated Parkin function may precipitate neuronal demise in various neurodegenerative disorders.
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Affiliation(s)
- Cheng-Wu Zhang
- Neurodegeneration Research Laboratory, National Neuroscience InstituteSingapore, Singapore; Institute of Advanced Materials, Nanjing Tech UniversityNanjing, People's Republic of China
| | - Liting Hang
- Department of Physiology, National University of Singapore Singapore, Singapore
| | - Tso-Pang Yao
- Departments of Pharmacology and Cancer Biology, Duke University Medical Center Durham, NC, USA
| | - Kah-Leong Lim
- Neurodegeneration Research Laboratory, National Neuroscience InstituteSingapore, Singapore; Institute of Advanced Materials, Nanjing Tech UniversityNanjing, People's Republic of China; Department of Physiology, National University of SingaporeSingapore, Singapore; Duke-NUS Graduate Medical School, National University of SingaporeSingapore, Singapore
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26
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Lonskaya I, Hebron ML, Selby ST, Turner RS, Moussa CEH. Nilotinib and bosutinib modulate pre-plaque alterations of blood immune markers and neuro-inflammation in Alzheimer's disease models. Neuroscience 2015; 304:316-27. [PMID: 26235435 DOI: 10.1016/j.neuroscience.2015.07.070] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Revised: 07/15/2015] [Accepted: 07/25/2015] [Indexed: 01/08/2023]
Abstract
Alzheimer's disease (AD) brains exhibit plaques and tangles in association with inflammation. The non-receptor tyrosine kinase Abl is linked to neuro-inflammation in AD. Abl inhibition by nilotinib or bosutinib facilitates amyloid clearance and may decrease inflammation. Transgenic mice that express Dutch, Iowa and Swedish APP mutations (TgAPP) and display progressive Aβ plaque deposition were treated with tyrosine kinase inhibitors (TKIs) to determine pre-plaque effects on systemic and CNS inflammation using milliplex® ELISA. Plaque Aβ was detected at 4months in TgAPP and pre-plaque intracellular Aβ accumulation (2.5months) was associated with changes of cytokines and chemokines prior to detection of glial changes. Plaque formation correlated with increased levels of pro-inflammatory cytokines (TNF-α, IL-6, IL-1α, IL-1β) and markers of immunosuppressive and adaptive immunity, including, IL-4, IL-10, IL-2, IL-3, Vascular Endothelial Growth Factor (VEGF) and IFN-γ. An inverse relationship of chemokines was observed as CCL2 and CCL5 were lower than WT mice at 2months and significantly increased after plaque appearance, while soluble CX3CL1 decreased. A change in glial profile was only robustly detected at 6months in Tg-APP mice and TKIs reduced astrocyte and dendritic cell number with no effects on microglia, suggesting alteration of brain immunity. Nilotinib decreased blood and brain cytokines and chemokines and increased CX3CL1. Bosutinib increased brain and blood IL-10 and CX3CL1, suggesting a protective role for soluble CX3CL1. Taken together these data suggest that TKIs regulate systemic and CNS immunity and may be useful treatments in early AD through dual effects on amyloid clearance and immune modulation.
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Affiliation(s)
- I Lonskaya
- Department of Neurology, Laboratory for Dementia and Parkinsonism, Georgetown University Medical Center, Washington D.C. 20007, USA
| | - M L Hebron
- Department of Neurology, Laboratory for Dementia and Parkinsonism, Georgetown University Medical Center, Washington D.C. 20007, USA
| | - S T Selby
- Department of Neurology, Laboratory for Dementia and Parkinsonism, Georgetown University Medical Center, Washington D.C. 20007, USA
| | - R S Turner
- Department of Neurology, Memory Disorders Program, Georgetown University Medical Center, Washington D.C. 20007, USA
| | - C E-H Moussa
- Department of Neurology, Laboratory for Dementia and Parkinsonism, Georgetown University Medical Center, Washington D.C. 20007, USA.
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Moussa CEH. Parkin Is Dispensable for Mitochondrial Function, but Its Ubiquitin Ligase Activity Is Critical for Macroautophagy and Neurotransmitters: Therapeutic Potential beyond Parkinson's Disease. NEURODEGENER DIS 2015; 15:259-70. [DOI: 10.1159/000430888] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Accepted: 04/23/2015] [Indexed: 11/19/2022] Open
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Charan RA, LaVoie MJ. Pathologic and therapeutic implications for the cell biology of parkin. Mol Cell Neurosci 2015; 66:62-71. [PMID: 25697646 DOI: 10.1016/j.mcn.2015.02.008] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Revised: 02/07/2015] [Accepted: 02/15/2015] [Indexed: 01/07/2023] Open
Abstract
Mutations in the E3 ligase parkin are the most common cause of autosomal recessive Parkinson's disease (PD), but it is believed that parkin dysfunction may also contribute to idiopathic PD. Since its discovery, parkin has been implicated in supporting multiple neuroprotective pathways, many revolving around the maintenance of mitochondrial health quality control and governance of cell survival. Recent advances across the structure, biochemistry, and cell biology of parkin have provided great insights into the etiology of parkin-linked and idiopathic PD and may ultimately generate novel therapeutic strategies to slow or halt disease progression. This review describes the various pathways in which parkin acts and the mechanisms by which parkin may be targeted for therapeutic intervention. This article is part of a Special Issue entitled 'Neuronal Protein'.
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Affiliation(s)
- Rakshita A Charan
- Ann Romney Center for Neurologic Diseases, Department of Neurology, Brigham and Women's Hospital, Boston, USA; Harvard Medical School, Boston, USA
| | - Matthew J LaVoie
- Ann Romney Center for Neurologic Diseases, Department of Neurology, Brigham and Women's Hospital, Boston, USA; Harvard Medical School, Boston, USA
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Corsetti V, Florenzano F, Atlante A, Bobba A, Ciotti MT, Natale F, Della Valle F, Borreca A, Manca A, Meli G, Ferraina C, Feligioni M, D'Aguanno S, Bussani R, Ammassari-Teule M, Nicolin V, Calissano P, Amadoro G. NH2-truncated human tau induces deregulated mitophagy in neurons by aberrant recruitment of Parkin and UCHL-1: implications in Alzheimer's disease. Hum Mol Genet 2015; 24:3058-81. [PMID: 25687137 DOI: 10.1093/hmg/ddv059] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Accepted: 02/10/2015] [Indexed: 01/26/2023] Open
Abstract
Disarrangement in functions and quality control of mitochondria at synapses are early events in Alzheimer's disease (AD) pathobiology. We reported that a 20-22 kDa NH2-tau fragment mapping between 26 and 230 amino acids of the longest human tau isoform (aka NH2htau): (i) is detectable in cellular and animal AD models, as well in synaptic mitochondria and cerebrospinal fluids (CSF) from human AD subjects; (ii) is neurotoxic in primary hippocampal neurons; (iii) compromises the mitochondrial biology both directly, by inhibiting the ANT-1-dependent ADP/ATP exchange, and indirectly, by impairing their selective autophagic clearance (mitophagy). Here, we show that the extensive Parkin-dependent turnover of mitochondria occurring in NH2htau-expressing post-mitotic neurons plays a pro-death role and that UCHL-1, the cytosolic Ubiquitin-C-terminal hydrolase L1 which directs the physiological remodeling of synapses by controlling ubiquitin homeostasis, critically contributes to mitochondrial and synaptic failure in this in vitro AD model. Pharmacological or genetic suppression of improper mitophagy, either by inhibition of mitochondrial targeting to autophagosomes or by shRNA-mediated silencing of Parkin or UCHL-1 gene expression, restores synaptic and mitochondrial content providing partial but significant protection against the NH2htau-induced neuronal death. Moreover, in mitochondria from human AD synapses, the endogenous NH2htau is stably associated with Parkin and with UCHL-1. Taken together, our studies show a causative link between the excessive mitochondrial turnover and the NH2htau-induced in vitro neuronal death, suggesting that pathogenetic tau truncation may contribute to synaptic deterioration in AD by aberrant recruitment of Parkin and UCHL-1 to mitochondria making them more prone to detrimental autophagic clearance.
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Affiliation(s)
- V Corsetti
- Institute of Translational Pharmacology (IFT) - National Research Council (CNR), Via Fosso del Cavaliere 100-00133, Rome, Italy
| | - F Florenzano
- European Brain Research Institute (EBRI), Via del Fosso di Fiorano 64-65, 00143 Rome, Italy
| | - A Atlante
- Institute of Biomembranes and Bioenergetics (IBBE)-CNR, Via Amendola 165/A, 70126 Bari, Italy
| | - A Bobba
- Institute of Biomembranes and Bioenergetics (IBBE)-CNR, Via Amendola 165/A, 70126 Bari, Italy
| | - M T Ciotti
- Institute of Cellular Biology and Neuroscience (IBCN)-CNR, IRCSS Santa Lucia Foundation Via del Fosso di Fiorano 64-65, 00143 Rome, Italy
| | - F Natale
- Institute of Cellular Biology and Neuroscience (IBCN)-CNR, IRCSS Santa Lucia Foundation Via del Fosso di Fiorano 64-65, 00143 Rome, Italy
| | - F Della Valle
- Institute of Cellular Biology and Neuroscience (IBCN)-CNR, IRCSS Santa Lucia Foundation Via del Fosso di Fiorano 64-65, 00143 Rome, Italy
| | - A Borreca
- Institute of Cellular Biology and Neuroscience (IBCN)-CNR, IRCSS Santa Lucia Foundation Via del Fosso di Fiorano 64-65, 00143 Rome, Italy
| | - A Manca
- European Brain Research Institute (EBRI), Via del Fosso di Fiorano 64-65, 00143 Rome, Italy
| | - G Meli
- European Brain Research Institute (EBRI), Via del Fosso di Fiorano 64-65, 00143 Rome, Italy
| | - C Ferraina
- European Brain Research Institute (EBRI), Via del Fosso di Fiorano 64-65, 00143 Rome, Italy
| | - M Feligioni
- European Brain Research Institute (EBRI), Via del Fosso di Fiorano 64-65, 00143 Rome, Italy
| | - S D'Aguanno
- Institute of Cellular Biology and Neuroscience (IBCN)-CNR, IRCSS Santa Lucia Foundation Via del Fosso di Fiorano 64-65, 00143 Rome, Italy
| | - R Bussani
- UCO Pathological Anatomy and Histopathology Unit, Cattinara Hospital Strada di Fiume 447, 34149 Trieste, Italy and
| | - M Ammassari-Teule
- Institute of Cellular Biology and Neuroscience (IBCN)-CNR, IRCSS Santa Lucia Foundation Via del Fosso di Fiorano 64-65, 00143 Rome, Italy
| | - V Nicolin
- Department of Medical, Surgical and Health Science, University of Trieste, Strada di Fiume 449, 34149 Trieste, Italy
| | - P Calissano
- European Brain Research Institute (EBRI), Via del Fosso di Fiorano 64-65, 00143 Rome, Italy
| | - G Amadoro
- Institute of Translational Pharmacology (IFT) - National Research Council (CNR), Via Fosso del Cavaliere 100-00133, Rome, Italy European Brain Research Institute (EBRI), Via del Fosso di Fiorano 64-65, 00143 Rome, Italy
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Abstract
SIGNIFICANCE Impairment of the ubiquitin-proteasome system (UPS) has been implicated in the pathogenesis of a wide variety of neurodegenerative disorders, including Alzheimer's, Parkinson's, and Huntington's diseases. The most significant risk factor for the development of these disorders is aging, which is associated with a progressive decline in UPS activity and the accumulation of oxidatively modified proteins. To date, no therapies have been developed that can specifically up-regulate this system. RECENT ADVANCES In the neurodegenerative brain, dysfunction of the UPS has been associated with the deposition of ubiquitinated protein aggregates and widespread disruption of the proteostasis network. Recent research has identified further evidence of impairment in substrate ubiquitination and proteasomal degradation, which could contribute to the loss of cellular proteostasis in neurodegenerative disease. Novel strategies for activation of the UPS by genetic manipulation and treatment with synthetic compounds have also recently been identified. CRITICAL ISSUES Here, we discuss the specific roles of the UPS in the healthy central nervous system and establish how dysfunctional components can contribute to neurotoxicity in the context of disease. FUTURE DIRECTIONS Knowledge of the UPS components that are specifically or preferentially involved in neurodegenerative disease will be critical in the development of targeted therapies which aim at limiting the accumulation of misfolded proteins without gross disturbance of this major proteolytic pathway.
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Affiliation(s)
- Chris McKinnon
- Department of Neurodegenerative Disease, University College London Institute of Neurology , London, United Kingdom
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Lonskaya I, Hebron M, Chen W, Schachter J, Moussa C. Tau deletion impairs intracellular β-amyloid-42 clearance and leads to more extracellular plaque deposition in gene transfer models. Mol Neurodegener 2014; 9:46. [PMID: 25384392 PMCID: PMC4247762 DOI: 10.1186/1750-1326-9-46] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Accepted: 10/21/2014] [Indexed: 01/02/2023] Open
Abstract
Background Tau is an axonal protein that binds to and regulates microtubule function. Hyper-phosphorylation of Tau reduces its binding to microtubules and it is associated with β-amyloid deposition in Alzheimer’s disease. Paradoxically, Tau reduction may prevent β-amyloid pathology, raising the possibility that Tau mediates intracellular Aβ clearance. The current studies investigated the role of Tau in autophagic and proteasomal intracellular Aβ1-42 clearance and the subsequent effect on plaque deposition. Results Tau deletion impaired Aβ clearance via autophagy, but not the proteasome, while introduction of wild type human Tau into Tau−/− mice partially restored autophagic clearance of Aβ1-42, suggesting that exogenous Tau expression can support autophagic Aβ1-42 clearance. Tau deletion impaired autophagic flux and resulted in Aβ1-42 accumulation in pre-lysosomal autophagic vacuoles, affecting Aβ1-42 deposition into the lysosome. This autophagic defect was associated with decreased intracellular Aβ1-42 and increased plaque load in Tau−/− mice, which displayed less cell death. Nilotinib, an Abl tyrosine kinase inhibitor that promotes autophagic clearance mechanisms, reduced Aβ1-42 only when exogenous human Tau was expressed in Tau−/− mice. Conclusions These studies demonstrate that Tau deletion affects intracellular Aβ1-42 clearance, leading to extracellular plaque. Electronic supplementary material The online version of this article (doi:10.1186/1750-1326-9-46) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | | | | | | | - Charbel Moussa
- Department of Neuroscience, Laboratory for Dementia and Parkinsonism, Georgetown University Medical Center, 3970 Reservoir RD, Washington, DC 20057, USA.
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Zhao W, Zhang J, Davis EG, Rebeck GW. Aging reduces glial uptake and promotes extracellular accumulation of Aβ from a lentiviral vector. Front Aging Neurosci 2014; 6:210. [PMID: 25177293 PMCID: PMC4133689 DOI: 10.3389/fnagi.2014.00210] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Accepted: 07/28/2014] [Indexed: 01/27/2023] Open
Abstract
We used a lentiviral system for expressing secreted human Aβ in the brains of young and old APOE knock-in mice. This system allowed us to examine Aβ metabolism in vivo, and test the effects of both aging and APOE genotype, two of the strongest risk factors for Alzheimer’s disease. We injected the Aβ1-42 lentivirus into the motor cortex of young (2 month old) and old (20–22 month old) APOE3 and APOE4 mice. After 2 weeks of lentiviral expression, we analyzed the pattern of Aβ accumulation, glial activation, and phosphor-tau. In young mice, Aβ accumulated mainly within neurons with no evidence of extracellular Aβ. Significantly higher levels of intraneuronal Aβ were observed in APOE4 mice compared to APOE3 mice. In old mice, APOE4 predisposed again to higher levels of Aβ accumulation, but the Aβ was mainly in extracellular spaces. In younger mice, we also observed Aβ in microglia but not astrocytes. The numbers of microglia containing Aβ were significantly higher in APOE3 mice compared to APOE4 mice, and were significantly lower in both genetic backgrounds with aging. The astrocytes in old mice were activated to a greater extent in the brain regions where Aβ was introduced, an effect that was again increased by the presence of APOE4. Finally, phospho-tau accumulated in the region of Aβ expression, with evidence of extracellular phospho-tau increasing with aging. These data suggest that APOE4 predisposes to less microglial clearance of Aβ, leading to more intraneuronal accumulation. In older brains, decreased clearance leads to more extracellular Aβ, and more downstream consequences relating to astrocyte activation and phospho-tau accumulation. We conclude that both aging and APOE genotype affect pathways related to Aβ metabolism by microglia.
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Affiliation(s)
- Wenjuan Zhao
- School of Pharmacy, Shanghai Jiao Tong University Shanghai, China
| | - Jiguo Zhang
- Department of Pharmacology, School of Pharmacy, Taishan Medical University Taian, China
| | - Elizabeth G Davis
- Department of Neuroscience, Georgetown University Medical Center Washington, DC, USA
| | - G William Rebeck
- Department of Neuroscience, Georgetown University Medical Center Washington, DC, USA
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Alternative splicing generates different parkin protein isoforms: evidences in human, rat, and mouse brain. BIOMED RESEARCH INTERNATIONAL 2014; 2014:690796. [PMID: 25136611 PMCID: PMC4124806 DOI: 10.1155/2014/690796] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Accepted: 06/30/2014] [Indexed: 11/17/2022]
Abstract
Parkinson protein 2, E3 ubiquitin protein ligase (PARK2) gene mutations are the most frequent causes of autosomal recessive early onset Parkinson's disease and juvenile Parkinson disease. Parkin deficiency has also been linked to other human pathologies, for example, sporadic Parkinson disease, Alzheimer disease, autism, and cancer. PARK2 primary transcript undergoes an extensive alternative splicing, which enhances transcriptomic diversification. To date several PARK2 splice variants have been identified; however, the expression and distribution of parkin isoforms have not been deeply investigated yet. Here, the currently known PARK2 gene transcripts and relative predicted encoded proteins in human, rat, and mouse are reviewed. By analyzing the literature, we highlight the existing data showing the presence of multiple parkin isoforms in the brain. Their expression emerges from conflicting results regarding the electrophoretic mobility of the protein, but it is also assumed from discrepant observations on the cellular and tissue distribution of parkin. Although the characterization of each predicted isoforms is complex, since they often diverge only for few amino acids, analysis of their expression patterns in the brain might account for the different pathogenetic effects linked to PARK2 gene mutations.
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La Cognata V, Iemmolo R, D'Agata V, Scuderi S, Drago F, Zappia M, Cavallaro S. Increasing the Coding Potential of Genomes Through Alternative Splicing: The Case of PARK2 Gene. Curr Genomics 2014; 15:203-16. [PMID: 24955028 PMCID: PMC4064560 DOI: 10.2174/1389202915666140426003342] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2014] [Revised: 04/05/2014] [Accepted: 04/23/2014] [Indexed: 01/28/2023] Open
Abstract
The completion of the Human Genome Project aroused renewed interest in alternative splicing, an efficient and widespread mechanism that generates multiple protein isoforms from individual genes. Although our knowledge about alternative splicing is growing exponentially, its real impact on cellular life is still to be clarified. Connecting all splicing features (genes, splice transcripts, isoforms, and relative functions) may be useful to resolve this tangle. Herein, we will start from the case of a single gene, Parkinson protein 2, E3 ubiquitin protein ligase (PARK2), one of the largest in our genome. This gene is implicated in the pathogenesis of autosomal recessive juvenile Parkinsonism and it has been recently linked to cancer, leprosy, autism, type 2 diabetes mellitus and Alzheimer’s disease. PARK2 primary transcript undergoes an extensive alternative splicing, which enhances transcriptomic diversification and protein diversity in tissues and cells. This review will provide an update of all human PARK2 alternative splice transcripts and isoforms presently known, and correlate them to those in rat and mouse, two common animal models for studying human disease genes. Alternative splicing relies upon a complex process that could be easily altered by both cis and trans-acting mutations. Although the contribution of PARK2 splicing in human disease remains to be fully explored, some evidences show disruption of this versatile form of genetic regulation may have pathological consequences.
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Affiliation(s)
- Valentina La Cognata
- 1Functional Genomics Center, Institute of Neurological Sciences, Italian National Research Council, Via Paolo Gaifami 18, 95125, Catania, Italy
| | - Rosario Iemmolo
- 1Functional Genomics Center, Institute of Neurological Sciences, Italian National Research Council, Via Paolo Gaifami 18, 95125, Catania, Italy
| | - Velia D'Agata
- 2Department of Bio-Medical Sciences, Section of Anatomy and Histology, University of Catania, Italy
| | - Soraya Scuderi
- 2Department of Bio-Medical Sciences, Section of Anatomy and Histology, University of Catania, Italy
| | - Filippo Drago
- 3Department of Clinical and Molecular Biomedicine, Section of Pharmacology and Biochemistry, University of Catania, Italy
| | - Mario Zappia
- 4Department "G.F. Ingrassia", Section of Neuroscience, University of Catania, Italy
| | - Sebastiano Cavallaro
- 1Functional Genomics Center, Institute of Neurological Sciences, Italian National Research Council, Via Paolo Gaifami 18, 95125, Catania, Italy
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Hong L, Huang HC, Jiang ZF. Relationship between amyloid-beta and the ubiquitin–proteasome system in Alzheimer’s disease. Neurol Res 2014; 36:276-82. [DOI: 10.1179/1743132813y.0000000288] [Citation(s) in RCA: 90] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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36
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Abstract
Ubiquitin-dependent proteolysis is a major mechanism that downregulates misfolded proteins or those that have finished a programmed task. In the last two decades, neddylation has emerged as a major regulatory pathway for ubiquitination. Central to the neddylation pathway is the amyloid precursor protein (APP)-binding protein APP-BP1, which together with Uba3, plays an analogous role to the ubiquitin-activating enzyme E1 in nedd8 activation. Activated nedd8 covalently modifies and activates a major class of ubiquitin ligases called Cullin-RING ligases (CRLs). New evidence suggests that neddylation also modifies Type-1 transmembrane receptors such as APP. Here we review the functions of neddylation and summarize evidence suggesting that dysfunction of neddylation is involved in Alzheimer's disease.
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Affiliation(s)
- Yuzhi Chen
- Department of Geriatrics and Department of Neurobiology & Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA.
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Lonskaya I, Desforges NM, Hebron ML, Moussa CEH. Ubiquitination increases parkin activity to promote autophagic α-synuclein clearance. PLoS One 2013; 8:e83914. [PMID: 24386307 PMCID: PMC3873413 DOI: 10.1371/journal.pone.0083914] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Accepted: 11/11/2013] [Indexed: 12/13/2022] Open
Abstract
Parkinson’s disease (PD) is a movement disorder associated with genetic and age related causes. Although autosomal recessive early onset PD linked to parkin mutations does not exhibit α-Synuclein accumulation, while autosomal dominant and sporadic PD manifest with α-Synuclein inclusions, loss of dopaminergic substantia nigra neurons is a common denominator in PD. Here we show that decreased parkin ubiquitination and loss of parkin stability impair interaction with Beclin-1 and alter α-Synuclein degradation, leading to death of dopaminergic neurons. Tyrosine kinase inhibition increases parkin ubiquitination and interaction with Beclin-1, promoting autophagic α-Synuclein clearance and nigral neuron survival. However, loss of parkin via deletion increases α-Synuclein in the blood compared to the brain, suggesting that functional parkin prevents α-Synuclein release into the blood. These studies demonstrate that parkin ubiquitination affects its protein stability and E3 ligase activity, possibly leading to α-Synuclein sequestration and subsequent clearance.
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Affiliation(s)
- Irina Lonskaya
- Department of Neuroscience, Laboratory for Dementia and Parkinsonism, Georgetown University Medical Center, Washington, DC, United States of America
| | - Nicole M. Desforges
- Department of Neuroscience, Laboratory for Dementia and Parkinsonism, Georgetown University Medical Center, Washington, DC, United States of America
| | - Michaeline L. Hebron
- Department of Neuroscience, Laboratory for Dementia and Parkinsonism, Georgetown University Medical Center, Washington, DC, United States of America
| | - Charbel E-H. Moussa
- Department of Neuroscience, Laboratory for Dementia and Parkinsonism, Georgetown University Medical Center, Washington, DC, United States of America
- * E-mail:
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Rankin CA, Galeva NA, Bae K, Ahmad MN, Witte TM, Richter ML. Isolated RING2 domain of parkin is sufficient for E2-dependent E3 ligase activity. Biochemistry 2013; 53:225-34. [PMID: 24328108 DOI: 10.1021/bi401378p] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The E3 ubiquitin ligase activity of the parkin protein is implicated in playing a protective role against neurodegenerative disorders including Parkinson's, Huntington's, and Alzheimer's diseases. Parkin has four zinc-containing domains: RING0, RING1, IBR (in-between ring), and RING2. Mutational analysis of full-length parkin suggests that the C-terminal RING2 domain contains the catalytic core. Here, a catalytically competent recombinant RING2 containing an N-terminal GB1 solubility peptide is described. In cell-free in vitro ubiqitination reactions, the RING2 construct catalyzes the transfer of ubiquitin from the E2 enzyme UbcH7 to the attached GB1 tag. This intramolecular autoubiquitination reaction indicates that (a) ubiquitination by RING2 can occur in the absence of other parkin domains and (b) UbcH7 can interact directly with RING2 to transfer its bound ubiquitin. Mass spectrometry identified sites of mono- and diubiquitin attachment to two surface-exposed lysine residues (Lys24 and Lys39) on the GB1 peptide. The sites of diubiquitination involved Lys11 and Lys48 linkages, which have been identified as general signals for proteasome degradation. Cleaving the linker between the GB1 tag and RING2 resulted in loss of ubiquitination activity, indicating that the substrate must be tethered to RING2 for proper presentation to the active site. Atomic absorption spectrometry and selective mutation of zinc ligands indicated that only one of the two zinc binding sites on RING2, the N-terminal site, needs to be occupied by zinc for expression of ubiquitination activity. This is consistent with the hypothesis that the second, C-terminal, zinc binding site on RING2 has a regulatory rather than a catalytic function.
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Affiliation(s)
- Carolyn A Rankin
- Departments of Molecular Biosciences and ‡Chemistry, §Analytical Proteomics Laboratory, The University of Kansas , Lawrence, Kansas 66044, United States
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Hebron M, Chen W, Miessau MJ, Lonskaya I, Moussa CEH. Parkin reverses TDP-43-induced cell death and failure of amino acid homeostasis. J Neurochem 2013; 129:350-61. [PMID: 24298989 DOI: 10.1111/jnc.12630] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Revised: 11/27/2013] [Accepted: 11/27/2013] [Indexed: 12/13/2022]
Abstract
The E3 ubiquitin ligase Parkin plays a central role in the pathogenesis of many neurodegenerative diseases. Parkin promotes specific ubiquitination and affects the localization of transactivation response DNA-binding protein 43 (TDP-43), which controls the translation of thousands of mRNAs. Here we tested the effects of lentiviral Parkin and TDP-43 expression on amino acid metabolism in the rat motor cortex using high frequency ¹³C NMR spectroscopy. TDP-43 expression increased glutamate levels, decreased the levels of other amino acids, including glutamine, aspartate, leucine and isoleucine, and impaired mitochondrial tricarboxylic acid cycle. TDP-43 induced lactate accumulation and altered the balance between excitatory (glutamate) and inhibitory (GABA) neurotransmitters. Parkin restored amino acid levels, neurotransmitter balance and tricarboxylic acid cycle metabolism, rescuing neurons from TDP-43-induced apoptotic death. Furthermore, TDP-43 expression led to an increase in 4E-BP levels, perhaps altering translational control and deregulating amino acid synthesis; while Parkin reversed the effects of TDP-43 on the 4E-BP signaling pathway. Taken together, these data suggest that Parkin may affect TDP-43 localization and mitigate its effects on 4E-BP signaling and loss of amino acid homeostasis.
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Affiliation(s)
- Michaeline Hebron
- Department of Neuroscience, Georgetown University Medical Center, Washington, District of Columbia, USA
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Lonskaya I, Hebron ML, Desforges NM, Schachter JB, Moussa CEH. Nilotinib-induced autophagic changes increase endogenous parkin level and ubiquitination, leading to amyloid clearance. J Mol Med (Berl) 2013; 92:373-86. [PMID: 24337465 DOI: 10.1007/s00109-013-1112-3] [Citation(s) in RCA: 106] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Revised: 11/15/2013] [Accepted: 11/28/2013] [Indexed: 12/13/2022]
Abstract
UNLABELLED Alzheimer's disease (AD) is a neurodegenerative disorder associated with amyloid accumulation and autophagic changes. Parkin is an E3 ubiquitin ligase involved in proteasomal and autophagic clearance. We previously demonstrated decreased parkin solubility and interaction with the key autophagy enzyme beclin-1 in AD, but tyrosine kinase inhibition restored parkin-beclin-1 interaction. In the current studies, we determined the mechanisms of nilotinib-induced parkin-beclin-1 interaction, which leads to amyloid clearance. Nilotinib increased endogenous parkin levels and ubiquitination, which may enhance parkin recycling via the proteasome, leading to increased activity and interaction with beclin-1. Parkin solubility was decreased and autophagy was altered in amyloid expressing mice, suggesting that amyloid stress affects parkin stability, leading to failure of protein clearance via the lysosome. Isolation of autophagic vacuoles revealed amyloid and parkin accumulation in autophagic compartments but nilotinib decreased insoluble parkin levels and facilitated amyloid deposition into lysosomes in wild type, but not parkin(-/-) mice, further underscoring an essential role for endogenous parkin in amyloid clearance. These results suggest that nilotinib boosts the autophagic machinery, leading to increased level of endogenous parkin that undergoes ubiquitination and interacts with beclin-1 to facilitate amyloid clearance. These data suggest that nilotinib-mediated autophagic changes may trigger parkin response via increased protein levels, providing a therapeutic strategy to reduce Aβ and Tau in AD. KEY MESSAGE Parkin solubility (stability) is decreased in AD and APP transgenic mice. Nilotinib-induced autophagic changes increase endogenous parkin level. Increased parkin level leads to ubiquitination and proteasomal recycling. Re-cycling decreases insoluble parkin and increases parkin-beclin-1 interaction. Beclin-1-parkin interaction enhances amyloid clearance.
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Affiliation(s)
- Irina Lonskaya
- Department of Neuroscience, Laboratory for Dementia and Parkinsonism, Georgetown University Medical Center, 3970 Reservoir Rd, NW, TRB, Room WP26B, Washington, DC, 20057, USA
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41
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Zhao W, Dumanis SB, Tamboli IY, Rodriguez GA, Jo Ladu M, Moussa CEH, William Rebeck G. Human APOE genotype affects intraneuronal Aβ1-42 accumulation in a lentiviral gene transfer model. Hum Mol Genet 2013; 23:1365-75. [PMID: 24154541 DOI: 10.1093/hmg/ddt525] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Intraneuronal accumulation of β-amyloid (Aβ)42 is one of the earliest pathological events in humans and in animal models of Alzheimer's disease (AD). Apolipoprotein E 4 (APOE4) is the major identified genetic risk factor for late-onset AD, with Aβ deposition beginning earlier in apoE4-positive subjects. To directly determine the effects of APOE genotype on intraneuronal accumulation of Aβ1-42 at the onset of AD pathogenesis, we introduced lentiviral Aβ1-42 into the cortex of APOE targeted replacement (TR) mice at the age of 8-9 months. We demonstrated a significant isoform-dependent effect of human APOE, with dramatically enhanced intracellular Aβ1-42 deposits in the cerebral cortex of APOE4-TR mice 2 weeks after injection. Double-immunofluorescent staining showed that intracellular accumulation of lentiviral Aβ1-42 was mainly present in neurons, localized to late endosomes/lysosomes. This intraneuronal accumulation of Aβ1-42 correlated with increased tau phosphorylation and cell death in the ipsilateral cortex around the injection site. Aβ1-42 was also observed in microglia, but not in astrocytes. Quantitative analysis revealed more neurons with Aβ1-42 while less microglia with Aβ1-42 nearest to the injection site of Aβ1-42 lentivirus in APOE4-TR mice. Finally, apoE was present in neurons of the ipsilateral cortex of APOE-TR mice at 2 weeks after lentivirus injection, in addition to astrocytes and microglia in both the ipsilateral and contralateral cerebral cortex. Taken together, these results demonstrate that apoE4 tips the balance of the glial and neuronal Aβ toward the intraneuronal accumulation of Aβ.
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Affiliation(s)
- Wenjuan Zhao
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai 200240, China
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42
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Hong X, Liu J, Zhu G, Zhuang Y, Suo H, Wang P, Huang D, Xu J, Huang Y, Yu M, Bian M, Sheng Z, Fei J, Song H, Behnisch T, Huang F. Parkin overexpression ameliorates hippocampal long-term potentiation and β-amyloid load in an Alzheimer's disease mouse model. Hum Mol Genet 2013; 23:1056-72. [PMID: 24105468 DOI: 10.1093/hmg/ddt501] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by a severe decline of memory performance. A widely studied AD mouse model is the APPswe/PSEN1ΔE9 (APP/PS1) strain, as mice exhibit amyloid plaques as well as impaired memory capacities. To test whether restoring synaptic plasticity and decreasing β-amyloid load by Parkin could represent a potential therapeutic target for AD, we crossed APP/PS1 transgenic mice with transgenic mice overexpressing the ubiquitin ligase Parkin and analyzed offspring properties. Overexpression of Parkin in APP/PS1 transgenic mice restored activity-dependent synaptic plasticity and rescued behavioral abnormalities. Moreover, overexpression of Parkin was associated with down-regulation of APP protein expression, decreased β-amyloid load and reduced inflammation. Our data suggest that Parkin could be a promising target for AD therapy.
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Affiliation(s)
- Xiaoqi Hong
- State Key Laboratory of Medical Neurobiology, Institutes of Brain Science, Shanghai Medical College, Fudan University, 138 Yixueyuan Road, Shanghai 200032, China
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43
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Checler F, Alves da Costa C. Interplay between Parkin and p53 Governs a Physiological Homeostasis That Is Disrupted in Parkinson's Disease and Cerebral Cancer. NEURODEGENER DIS 2013; 13:118-21. [DOI: 10.1159/000354075] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Accepted: 06/28/2013] [Indexed: 11/19/2022] Open
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Lonskaya I, Hebron ML, Desforges NM, Franjie A, Moussa CEH. Tyrosine kinase inhibition increases functional parkin-Beclin-1 interaction and enhances amyloid clearance and cognitive performance. EMBO Mol Med 2013; 5:1247-62. [PMID: 23737459 PMCID: PMC3944464 DOI: 10.1002/emmm.201302771] [Citation(s) in RCA: 111] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Revised: 05/21/2013] [Accepted: 05/22/2013] [Indexed: 12/12/2022] Open
Abstract
Tyrosine kinase inhibitors (TKIs) are effective therapies for leukaemia. Alzheimer is a neurodegenerative disease characterized by accumulation of β-amyloid (plaques) and hyper-phosphorylated Tau (tangles). Here we show that AD animals have high levels of insoluble parkin and decreased parkin-Beclin-1 interaction, while peripheral administration of TKIs, including Nilotinib and Bosutinib, increases soluble parkin leading to amyloid clearance and cognitive improvement. Blocking Beclin-1 expression with shRNA or parkin deletion prevents tyrosine kinase (TK) inhibition-induced amyloid clearance, suggesting that functional parkin-Beclin-1 interaction mediates amyloid degradation. Isolation of autophagic vacuoles (AVs) in AD mouse brain shows accumulation of parkin and amyloid, consistent with previous results in AD brains, while Bosutinib and Nilotinib increase parkin-Beclin-1 interaction and result in protein deposition in the lysosome. These data suggest that decreased parkin solubility impedes parkin-Beclin-1 interaction and amyloid clearance. We identified two FDA-approved anti-cancer drugs as potential treatment for AD. Two FDA-approved tyrosine kinase inhibitor drugs, Bosutinib and Nilotinib, are shown to ameliorate Alzheimer's disease pathology in mouse models by increasing soluble parkin and leading to amyloid clearance and cognitive improvement.
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Affiliation(s)
- Irina Lonskaya
- Department of Neuroscience, Laboratory for Dementia and Parkinsonism, Georgetown University Medical Center, Washington, DC, USA
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45
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Salminen A, Kaarniranta K, Kauppinen A, Ojala J, Haapasalo A, Soininen H, Hiltunen M. Impaired autophagy and APP processing in Alzheimer's disease: The potential role of Beclin 1 interactome. Prog Neurobiol 2013; 106-107:33-54. [DOI: 10.1016/j.pneurobio.2013.06.002] [Citation(s) in RCA: 198] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Revised: 06/12/2013] [Accepted: 06/18/2013] [Indexed: 12/18/2022]
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46
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Feng D, Liu L, Zhu Y, Chen Q. Molecular signaling toward mitophagy and its physiological significance. Exp Cell Res 2013; 319:1697-1705. [DOI: 10.1016/j.yexcr.2013.03.034] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Revised: 03/23/2013] [Accepted: 03/25/2013] [Indexed: 12/21/2022]
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47
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García-Escudero V, Martín-Maestro P, Perry G, Avila J. Deconstructing mitochondrial dysfunction in Alzheimer disease. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2013; 2013:162152. [PMID: 23840916 PMCID: PMC3693159 DOI: 10.1155/2013/162152] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Accepted: 05/23/2013] [Indexed: 11/17/2022]
Abstract
There is mounting evidence showing that mitochondrial damage plays an important role in Alzheimer disease. Increased oxygen species generation and deficient mitochondrial dynamic balance have been suggested to be the reason as well as the consequence of Alzheimer-related pathology. Mitochondrial damage has been related to amyloid-beta or tau pathology or to the presence of specific presenilin-1 mutations. The contribution of these factors to mitochondrial dysfunction is reviewed in this paper. Due to the relevance of mitochondrial alterations in Alzheimer disease, recent works have suggested the therapeutic potential of mitochondrial-targeted antioxidant. On the other hand, autophagy has been demonstrated to play a fundamental role in Alzheimer-related protein stress, and increasing data shows that this pathway is altered in the disease. Moreover, mitochondrial alterations have been related to an insufficient clearance of dysfunctional mitochondria by autophagy. Consequently, different approaches for the removal of damaged mitochondria or to decrease the related oxidative stress in Alzheimer disease have been described. To understand the role of mitochondrial function in Alzheimer disease it is necessary to generate human cellular models which involve living neurons. We have summarized the novel protocols for the generation of neurons by reprogramming or direct transdifferentiation, which offer useful tools to achieve this result.
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Affiliation(s)
- Vega García-Escudero
- Centro de Biología Molecular “Severo Ochoa” (CSIC-UAM), 28049 Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), 28031 Madrid, Spain
| | - Patricia Martín-Maestro
- Centro de Biología Molecular “Severo Ochoa” (CSIC-UAM), 28049 Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), 28031 Madrid, Spain
| | - George Perry
- University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Jesús Avila
- Centro de Biología Molecular “Severo Ochoa” (CSIC-UAM), 28049 Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), 28031 Madrid, Spain
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48
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Hebron ML, Lonskaya I, Moussa CEH. Nilotinib reverses loss of dopamine neurons and improves motor behavior via autophagic degradation of α-synuclein in Parkinson's disease models. Hum Mol Genet 2013; 22:3315-28. [PMID: 23666528 DOI: 10.1093/hmg/ddt192] [Citation(s) in RCA: 236] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Parkinson's disease is a movement disorder characterized by death of dopaminergic substantia nigra (SN) neurons and brain accumulation of α-synuclein. The tyrosine kinase Abl is activated in neurodegeneration. Here, we show that lentiviral expression of α-synuclein in the mouse SN leads to Abl activation (phosphorylation) and lentiviral Abl expression increases α-synuclein levels, in agreement with Abl activation in PD brains. Administration of the tyrosine kinase inhibitor nilotinib decreases Abl activity and ameliorates autophagic clearance of α-synuclein in transgenic and lentiviral gene transfer models. Subcellular fractionation shows accumulation of α-synuclein and hyper-phosphorylated Tau (p-Tau) in autophagic vacuoles in α-synuclein expressing brains, but nilotinib enhances protein deposition into the lysosomes. Nilotinib is used for adult leukemia treatment and it enters the brain within US Food and Drug Administration approved doses, leading to autophagic degradation of α-synuclein, protection of SN neurons and amelioration of motor performance. These data suggest that nilotinib may be a therapeutic strategy to degrade α-synuclein in PD and other α-synucleinopathies.
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Affiliation(s)
- Michaeline L Hebron
- Department of Neuroscience, Laboratory for Dementia and Parkinsonism, Georgetown University Medical Center, Washington, DC 20057, USA
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49
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Lecanu L, Papadopoulos V. Modeling Alzheimer's disease with non-transgenic rat models. ALZHEIMERS RESEARCH & THERAPY 2013; 5:17. [PMID: 23634826 PMCID: PMC3706888 DOI: 10.1186/alzrt171] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Alzheimer's disease (AD), for which there is no cure, is the most common form of dementia in the elderly. Despite tremendous efforts by the scientific community, the AD drug development pipeline remains extremely limited. Animal models of disease are a cornerstone of any drug development program and should be as relevant as possible to the disease, recapitulating the disease phenotype with high fidelity, to meaningfully contribute to the development of a successful therapeutic agent. Over the past two decades, transgenic models of AD based on the known genetic origins of familial AD have significantly contributed to our understanding of the molecular mechanisms involved in the onset and progression of the disease. These models were extensively used in AD drug development. The numerous reported failures of new treatments for AD in clinical trials indicate that the use of genetic models of AD may not represent the complete picture of AD in humans and that other types of animal models relevant to the sporadic form of the disease, which represents 95% of AD cases, should be developed. In this review, we will discuss the evolution of non-transgenic rat models of AD and how these models may open new avenues for drug development.
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Affiliation(s)
- Laurent Lecanu
- The Research Institute of the McGill University Health Centre, Royal Victoria Hospital, 687 Pine avenue West, room L2-05, Montreal H3A 1A1, QC, Canada ; Department of Medicine, McGill University, Royal Victoria Hospital, 687 Pine avenue West, room L2-05, Montreal H3A 1A1, QC, Canada
| | - Vassilios Papadopoulos
- The Research Institute of the McGill University Health Centre, Royal Victoria Hospital, 687 Pine avenue West, room L2-05, Montreal H3A 1A1, QC, Canada ; Department of Medicine, McGill University, Royal Victoria Hospital, 687 Pine avenue West, room L2-05, Montreal H3A 1A1, QC, Canada ; Departments of Biochemistry and Pharmacology and Therapeutics, McGill University, McIntyre Medical Sciences Bldg, 3655 Promenade Sir-William-Osler, room 1325, Montreal Quebec, Canada H3G 1Y6
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50
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Hebron ML, Lonskaya I, Sharpe K, Weerasinghe PPK, Algarzae NK, Shekoyan AR, Moussa CEH. Parkin ubiquitinates Tar-DNA binding protein-43 (TDP-43) and promotes its cytosolic accumulation via interaction with histone deacetylase 6 (HDAC6). J Biol Chem 2013; 288:4103-15. [PMID: 23258539 PMCID: PMC3567661 DOI: 10.1074/jbc.m112.419945] [Citation(s) in RCA: 102] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The importance of E3 ubiquitin ligases, involved in the degradation of misfolded proteins or promotion of protein-protein interaction, is increasingly recognized in neurodegeneration. TDP-43 is a predominantly nuclear protein, which regulates the transcription of thousands of genes and binds to mRNA of the E3 ubiquitin ligase Parkin to regulate its expression. Wild type and mutated TDP-43 are detected in ubiquitinated forms within the cytosol in several neurodegenerative diseases. We elucidated the mechanisms of TDP-43 interaction with Parkin using transgenic A315T mutant TDP-43 (TDP43-Tg) mice, lentiviral wild type TDP-43, and Parkin gene transfer rat models. TDP-43 expression increased Parkin mRNA and protein levels. Lentiviral TDP-43 increased the levels of nuclear and cytosolic protein, whereas Parkin co-expression mediated Lys-48 and Lys-63-linked ubiquitin to TDP-43 and led to cytosolic co-localization of Parkin with ubiquitinated TDP-43. Parkin and TDP-43 formed a multiprotein complex with HDAC6, perhaps to mediate TDP-43 translocation. In conclusion, Parkin ubiquitinates TDP-43 and facilitates its cytosolic accumulation through a multiprotein complex with HDAC6.
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Affiliation(s)
- Michaeline L. Hebron
- From the Department of Neuroscience, Georgetown University Medical Center, Washington, D. C. 20007
| | - Irina Lonskaya
- From the Department of Neuroscience, Georgetown University Medical Center, Washington, D. C. 20007
| | - Kaydee Sharpe
- From the Department of Neuroscience, Georgetown University Medical Center, Washington, D. C. 20007
| | | | - Norah K. Algarzae
- From the Department of Neuroscience, Georgetown University Medical Center, Washington, D. C. 20007
| | - Ashot R. Shekoyan
- From the Department of Neuroscience, Georgetown University Medical Center, Washington, D. C. 20007
| | - Charbel E.-H. Moussa
- From the Department of Neuroscience, Georgetown University Medical Center, Washington, D. C. 20007, To whom correspondence should be addressed: Laboratory for Dementia and Parkinsonism, Dept. of Neuroscience, Georgetown University School of Medicine, 3970 Reservoir Rd., NW, TRB, Rm. WP09B, Washington, D. C. 20057. Tel.: 202-687-7328; Fax: 202-687-0617; E-mail:
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