1
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Liu HN, Wang T, Hu JJ, Chen L, Shi X, Li YM, Luo SZ. The disordered protein SERF promotes α-Synuclein aggregation through liquid-liquid phase separation. J Biol Chem 2024; 300:105667. [PMID: 38272228 PMCID: PMC10877630 DOI: 10.1016/j.jbc.2024.105667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 12/26/2023] [Accepted: 12/28/2023] [Indexed: 01/27/2024] Open
Abstract
The aggregation of α-Synuclein (α-Syn) into amyloid fibrils is the hallmark of Parkinson's disease. Under stress or other pathological conditions, the accumulation of α-Syn oligomers is the main contributor to the cytotoxicity. A potential approach for treating Parkinson's disease involves preventing the accumulation of these α-Syn oligomers. In this study, we present a novel mechanism involving a conserved group of disorderly proteins known as small EDRK-rich factor (SERF), which promotes the aggregation of α-Syn through a cophase separation process. Using diverse methods like confocal microscopy, fluorescence recovery after photobleaching assays, solution-state NMR spectroscopy, and Western blot, we determined that the N-terminal domain of SERF1a plays a role in the interactions that occur during cophase separation. Within these droplets, α-Syn undergoes a gradual transformation from solid condensates to amyloid fibrils, while SERF1a is excluded from the condensates and dissolves into the solution. Notably, in vivo experiments show that SERF1a cophase separation with α-Syn significantly reduces the deposition of α-Syn oligomers and decreases its cellular toxicity under stress. These findings suggest that SERF1a accelerates the conversion of α-Syn from highly toxic oligomers to less toxic fibrils through cophase separation, thereby mitigating the biological damage of α-Syn aggregation.
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Affiliation(s)
- He-Ning Liu
- Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, China
| | - Ting Wang
- Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, China
| | - Jin-Jian Hu
- Key Lab of Bioorganic Phosphorus Chemistry & Chemical Biology, Department of Chemistry, Tsinghua University, Beijing, China
| | - Long Chen
- Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, China
| | - Xiangyan Shi
- Department of Biology, Shenzhen MSU-BIT University, Shenzhen, China.
| | - Yan-Mei Li
- Key Lab of Bioorganic Phosphorus Chemistry & Chemical Biology, Department of Chemistry, Tsinghua University, Beijing, China.
| | - Shi-Zhong Luo
- Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, China.
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2
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Saramowicz K, Siwecka N, Galita G, Kucharska-Lusina A, Rozpędek-Kamińska W, Majsterek I. Alpha-Synuclein Contribution to Neuronal and Glial Damage in Parkinson's Disease. Int J Mol Sci 2023; 25:360. [PMID: 38203531 PMCID: PMC10778752 DOI: 10.3390/ijms25010360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 12/18/2023] [Accepted: 12/21/2023] [Indexed: 01/12/2024] Open
Abstract
Parkinson's disease (PD) is a complex neurodegenerative disease characterized by the progressive loss of dopaminergic neurons in the substantia nigra and the widespread accumulation of alpha-synuclein (αSyn) protein aggregates. αSyn aggregation disrupts critical cellular processes, including synaptic function, mitochondrial integrity, and proteostasis, which culminate in neuronal cell death. Importantly, αSyn pathology extends beyond neurons-it also encompasses spreading throughout the neuronal environment and internalization by microglia and astrocytes. Once internalized, glia can act as neuroprotective scavengers, which limit the spread of αSyn. However, they can also become reactive, thereby contributing to neuroinflammation and the progression of PD. Recent advances in αSyn research have enabled the molecular diagnosis of PD and accelerated the development of targeted therapies. Nevertheless, despite more than two decades of research, the cellular function, aggregation mechanisms, and induction of cellular damage by αSyn remain incompletely understood. Unraveling the interplay between αSyn, neurons, and glia may provide insights into disease initiation and progression, which may bring us closer to exploring new effective therapeutic strategies. Herein, we provide an overview of recent studies emphasizing the multifaceted nature of αSyn and its impact on both neuron and glial cell damage.
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Affiliation(s)
| | | | | | | | | | - Ireneusz Majsterek
- Department of Clinical Chemistry and Biochemistry, Medical University of Lodz, 92-215 Lodz, Poland; (K.S.); (N.S.); (G.G.); (A.K.-L.); (W.R.-K.)
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3
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Bigi A, Cascella R, Cecchi C. α-Synuclein oligomers and fibrils: partners in crime in synucleinopathies. Neural Regen Res 2023; 18:2332-2342. [PMID: 37282450 PMCID: PMC10360081 DOI: 10.4103/1673-5374.371345] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023] Open
Abstract
The misfolding and aggregation of α-synuclein is the general hallmark of a group of devastating neurodegenerative pathologies referred to as synucleinopathies, such as Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy. In such conditions, a range of different misfolded aggregates, including oligomers, protofibrils, and fibrils, are present both in neurons and glial cells. Growing experimental evidence supports the proposition that soluble oligomeric assemblies, formed during the early phases of the aggregation process, are the major culprits of neuronal toxicity; at the same time, fibrillar conformers appear to be the most efficient at propagating among interconnected neurons, thus contributing to the spreading of α-synuclein pathology. Moreover, α-synuclein fibrils have been recently reported to release soluble and highly toxic oligomeric species, responsible for an immediate dysfunction in the recipient neurons. In this review, we discuss the current knowledge about the plethora of mechanisms of cellular dysfunction caused by α-synuclein oligomers and fibrils, both contributing to neurodegeneration in synucleinopathies.
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Affiliation(s)
- Alessandra Bigi
- Department of Experimental and Clinical Biomedical Sciences, Section of Biochemistry, University of Florence, Florence, Italy
| | - Roberta Cascella
- Department of Experimental and Clinical Biomedical Sciences, Section of Biochemistry, University of Florence, Florence, Italy
| | - Cristina Cecchi
- Department of Experimental and Clinical Biomedical Sciences, Section of Biochemistry, University of Florence, Florence, Italy
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4
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Pinky, Neha, Salman M, Kumar P, Khan MA, Jamal A, Parvez S. Age-related pathophysiological alterations in molecular stress markers and key modulators of hypoxia. Ageing Res Rev 2023; 90:102022. [PMID: 37490963 DOI: 10.1016/j.arr.2023.102022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Revised: 06/30/2023] [Accepted: 07/21/2023] [Indexed: 07/27/2023]
Abstract
Alzheimer's disease (AD) is characterized by an adverse cellular environment and pathological alterations in distinct brain regions. The development is triggered or facilitated by a condition such as hypoxia or ischemia, or inflammation and is associated with disruptions of fundamental cellular functions, including metabolic and ion homeostasis. Increasing evidence suggests that hypoxia may affect many pathological aspects of AD, including oxidative stress, mitochondrial dysfunction, ER stress, amyloidogenic processing of APP, and Aβ accumulation, which may collectively result in neurodegeneration. Further investigation into the relationship between hypoxia and AD may provide an avenue for the effective preservation and pharmacological treatment of this neurodegenerative disease. This review summarizes the effects of normoxia and hypoxia on AD pathogenesis and discusses the underlying mechanisms. Regulation of HIF-1α and the role of its key players, including P53, VEGF, and GLUT1, are also discussed.
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Affiliation(s)
- Pinky
- Department of Toxicology, School of Chemical and Life Sciences, Jamia Hamdard, New Delhi 110062, India.
| | - Neha
- Department of Toxicology, School of Chemical and Life Sciences, Jamia Hamdard, New Delhi 110062, India.
| | - Mohd Salman
- Department of Toxicology, School of Chemical and Life Sciences, Jamia Hamdard, New Delhi 110062, India.
| | - Pratika Kumar
- Department of Toxicology, School of Chemical and Life Sciences, Jamia Hamdard, New Delhi 110062, India.
| | - Mohammad Ahmed Khan
- Department of Pharmacology, School of Pharmaceutical Education and Research, Jamia Hamdard, New Delhi, India.
| | - Azfar Jamal
- Department of Biology, College of Science, Al-Zulfi-, Majmaah University, Al-Majmaah 11952, Saudi Arabia; Health and Basic Science Research Centre, Majmaah University, Al-Majmaah 11952, Saudi Arabia.
| | - Suhel Parvez
- Department of Toxicology, School of Chemical and Life Sciences, Jamia Hamdard, New Delhi 110062, India.
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5
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Suthar SK, Lee SY. Truncation or proteolysis of α-synuclein in Parkinsonism. Ageing Res Rev 2023; 90:101978. [PMID: 37286088 DOI: 10.1016/j.arr.2023.101978] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2022] [Revised: 05/28/2023] [Accepted: 06/03/2023] [Indexed: 06/09/2023]
Abstract
Posttranslational modifications of α-synuclein, such as truncation or abnormal proteolysis, are implicated in Parkinson's disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA). A key focus of this article includes the proteases responsible for inducing truncation, the specific sites susceptible to truncation, and the resultant influence of these truncated species on the seeding and aggregation of endogenous α-synuclein. We also shed light on the unique structural attributes of these truncated species, and how these modifications can lead to distinctive forms of synucleinopathies. In addition, we explore the comparative toxic potentials of various α-synuclein species. An extensive analysis of available evidence of truncated α-synuclein species in human-synucleinopathy brains is also provided. Lastly, we delve into the detrimental impact of truncated species on key cellular structures such as the mitochondria and endoplasmic reticulum. Our article discusses enzymes involved in α-synuclein truncation, including 20 S proteasome, cathepsins, asparagine endopeptidase, caspase-1, calpain-1, neurosin/kallikrein-6, matrix metalloproteinase-1/-3, and plasmin. Truncation patterns impact α-synuclein aggregation - C-terminal truncation accelerates aggregation with larger truncations correlated with shortened aggregation lag times. N-terminal truncation affects aggregation differently based on the truncation location. C-terminally truncated α-synuclein forms compact, shorter fibrils compared to the full-length (FL) protein. N-terminally truncated monomers form fibrils similar in length to FL α-synuclein. Truncated forms show distinct fibril morphologies, increased β-sheet structures, and greater protease resistance. Misfolded α-synuclein can adopt various conformations, leading to unique aggregates and distinct synucleinopathies. Fibrils, with prion-like transmission, are potentially more toxic than oligomers, though this is still debated. Different α-synuclein variants with N- and C-terminal truncations, namely 5-140, 39-140, 65-140, 66-140, 68-140, 71-140, 1-139, 1-135, 1-133, 1-122, 1-119, 1-115, 1-110, and 1-103 have been found in PD, DLB, and MSA patients' brains. In Parkinsonism, excess misfolded α-synuclein overwhelms the proteasome degradation system, resulting in truncated protein production and accumulation in the mitochondria and endoplasmic reticulum.
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Affiliation(s)
| | - Sang-Yoon Lee
- Neuroscience Research Institute, Gachon University, Incheon, South Korea; Department of Neuroscience, College of Medicine, Gachon University, Incheon, South Korea.
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6
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Siwecka N, Saramowicz K, Galita G, Rozpędek-Kamińska W, Majsterek I. Inhibition of Protein Aggregation and Endoplasmic Reticulum Stress as a Targeted Therapy for α-Synucleinopathy. Pharmaceutics 2023; 15:2051. [PMID: 37631265 PMCID: PMC10459316 DOI: 10.3390/pharmaceutics15082051] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 07/22/2023] [Accepted: 07/28/2023] [Indexed: 08/27/2023] Open
Abstract
α-synuclein (α-syn) is an intrinsically disordered protein abundant in the central nervous system. Physiologically, the protein regulates vesicle trafficking and neurotransmitter release in the presynaptic terminals. Pathologies related to misfolding and aggregation of α-syn are referred to as α-synucleinopathies, and they constitute a frequent cause of neurodegeneration. The most common α-synucleinopathy, Parkinson's disease (PD), is caused by abnormal accumulation of α-syn in the dopaminergic neurons of the midbrain. This results in protein overload, activation of endoplasmic reticulum (ER) stress, and, ultimately, neural cell apoptosis and neurodegeneration. To date, the available treatment options for PD are only symptomatic and rely on dopamine replacement therapy or palliative surgery. As the prevalence of PD has skyrocketed in recent years, there is a pending issue for development of new disease-modifying strategies. These include anti-aggregative agents that target α-syn directly (gene therapy, small molecules and immunization), indirectly (modulators of ER stress, oxidative stress and clearance pathways) or combine both actions (natural compounds). Herein, we provide an overview on the characteristic features of the structure and pathogenic mechanisms of α-syn that could be targeted with novel molecular-based therapies.
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Affiliation(s)
| | | | | | | | - Ireneusz Majsterek
- Department of Clinical Chemistry and Biochemistry, Medical University of Lodz, 92-215 Lodz, Poland; (N.S.); (K.S.); (G.G.); (W.R.-K.)
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7
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Canever JB, Soares ES, de Avelar NCP, Cimarosti HI. Targeting α-synuclein post-translational modifications in Parkinson's disease. Behav Brain Res 2023; 439:114204. [PMID: 36372243 DOI: 10.1016/j.bbr.2022.114204] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 10/25/2022] [Accepted: 11/04/2022] [Indexed: 11/13/2022]
Abstract
Parkinson's disease (PD) is a neurodegenerative disease characterized by the progressive loss of dopaminergic neurons in the nigrostriatal pathway. Although the exact mechanisms underlying PD are still not completely understood, it is well accepted that α-synuclein plays key pathophysiological roles as the main constituent of the cytoplasmic inclusions known as Lewy bodies. Several post-translational modifications (PTMs), such as the best-known phosphorylation, target α-synuclein and are thus implicated in its physiological and pathological functions. In this review, we present (1) an overview of the pathophysiological roles of α-synuclein, (2) a descriptive analysis of α-synuclein PTMs, including phosphorylation, ubiquitination, SUMOylation, acetylation, glycation, truncation, and O-GlcNAcylation, as well as (3) a brief summary on α-synuclein PTMs as potential biomarkers for PD. A better understanding of α-synuclein PTMs is of paramount importance for elucidating the mechanisms underlying PD and can thus be expected to improve early detection and monitoring disease progression, as well as identify promising new therapeutic targets.
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Affiliation(s)
- Jaquelini B Canever
- Post-Graduate Program in Neuroscience, Federal University of Santa Catarina (UFSC), Florianópolis, Santa Catarina, Brazil; Laboratory of Aging, Resources and Rheumatology, UFSC, Araranguá, Santa Catarina, Brazil
| | - Ericks Sousa Soares
- Post-Graduate Program in Pharmacology, UFSC, Florianópolis, Santa Catarina, Brazil
| | - Núbia C P de Avelar
- Laboratory of Aging, Resources and Rheumatology, UFSC, Araranguá, Santa Catarina, Brazil
| | - Helena I Cimarosti
- Post-Graduate Program in Neuroscience, Federal University of Santa Catarina (UFSC), Florianópolis, Santa Catarina, Brazil; Post-Graduate Program in Pharmacology, UFSC, Florianópolis, Santa Catarina, Brazil.
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8
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Galzitskaya OV, Grishin SY, Glyakina AV, Dovidchenko NV, Konstantinova AV, Kravchenko SV, Surin AK. The Strategies of Development of New Non-Toxic Inhibitors of Amyloid Formation. Int J Mol Sci 2023; 24:3781. [PMID: 36835194 PMCID: PMC9964835 DOI: 10.3390/ijms24043781] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 02/08/2023] [Accepted: 02/10/2023] [Indexed: 02/16/2023] Open
Abstract
In recent years, due to the aging of the population and the development of diagnostic medicine, the number of identified diseases associated with the accumulation of amyloid proteins has increased. Some of these proteins are known to cause a number of degenerative diseases in humans, such as amyloid-beta (Aβ) in Alzheimer's disease (AD), α-synuclein in Parkinson's disease (PD), and insulin and its analogues in insulin-derived amyloidosis. In this regard, it is important to develop strategies for the search and development of effective inhibitors of amyloid formation. Many studies have been carried out aimed at elucidating the mechanisms of amyloid aggregation of proteins and peptides. This review focuses on three amyloidogenic peptides and proteins-Aβ, α-synuclein, and insulin-for which we will consider amyloid fibril formation mechanisms and analyze existing and prospective strategies for the development of effective and non-toxic inhibitors of amyloid formation. The development of non-toxic inhibitors of amyloid will allow them to be used more effectively for the treatment of diseases associated with amyloid.
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Affiliation(s)
- Oxana V. Galzitskaya
- Institute of Protein Research, Russian Academy of Sciences, 142290 Pushchino, Russia
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, 142290 Pushchino, Russia
| | - Sergei Y. Grishin
- Institute of Protein Research, Russian Academy of Sciences, 142290 Pushchino, Russia
- Institute of Environmental and Agricultural Biology (X-BIO), Tyumen State University, 625003 Tyumen, Russia
| | - Anna V. Glyakina
- Institute of Protein Research, Russian Academy of Sciences, 142290 Pushchino, Russia
- Institute of Mathematical Problems of Biology RAS, The Branch of Keldysh Institute of Applied Mathematics, Russian Academy of Sciences, 142290 Pushchino, Russia
| | - Nikita V. Dovidchenko
- Institute of Protein Research, Russian Academy of Sciences, 142290 Pushchino, Russia
| | - Anastasiia V. Konstantinova
- Institute of Protein Research, Russian Academy of Sciences, 142290 Pushchino, Russia
- Faculty of Biotechnology, Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Sergey V. Kravchenko
- Institute of Environmental and Agricultural Biology (X-BIO), Tyumen State University, 625003 Tyumen, Russia
| | - Alexey K. Surin
- Institute of Protein Research, Russian Academy of Sciences, 142290 Pushchino, Russia
- The Branch of the Institute of Bioorganic Chemistry, Russian Academy of Sciences, 142290 Pushchino, Russia
- State Research Center for Applied Microbiology and Biotechnology, 142279 Obolensk, Russia
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9
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Hetz R, Magaway C, Everett J, Li L, Willard BB, Freeze HH, He P. Comparative proteomics reveals elevated CCN2 in NGLY1-deficient cells. Biochem Biophys Res Commun 2022; 632:165-172. [PMID: 36209585 PMCID: PMC9677521 DOI: 10.1016/j.bbrc.2022.09.100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 09/13/2022] [Accepted: 09/25/2022] [Indexed: 01/05/2023]
Abstract
N-glycanase 1(NGLY1) catalyzes the removal of N-linked glycans from newly synthesized or misfolded protein. NGLY1 deficiency is a recently diagnosed rare genetic disorder. The affected individuals present a broad spectrum of clinical features. Recent studies explored several possible molecular mechanisms of NGLY1 deficiency including defects in proteostasis, mitochondrial homeostasis, innate immunity, and water/ion transport. We demonstrate abnormal accumulation of endoplasmic reticulum-associated degradation (ERAD) substrates in NGLY1-deficient cells. Global quantitative proteomics discovered elevated levels of endogenous proteins in NGLY1-defective human and mouse cells. Further biological validation assays confirmed the altered abundance of several key candidates that were subjected to isobarically labeled proteomic analysis. CCN2 was selected for further analysis due to its significant increase in different cell models of NGLY1 deficiency. Functional assays show elevated CCN2 and over-stimulated TGF-β signaling in NGLY1-deficient cells. Given the important role of CCN2 and TGF-β pathway in mediating systemic fibrosis, we propose a potential link of increased CCN2 and TGF-β signaling to microscopic liver fibrosis in NGLY1 patients.
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Affiliation(s)
- Rebecca Hetz
- Department of Biochemistry, Lake Erie College of Osteopathic Medicine, Erie, PA, USA
| | - Carlo Magaway
- Department of Biochemistry, Lake Erie College of Osteopathic Medicine, Erie, PA, USA
| | - Jaylene Everett
- Department of Biochemistry, Lake Erie College of Osteopathic Medicine, Erie, PA, USA
| | - Ling Li
- Proteomics and Metabolomics Core, Cleveland Clinic Lerner Research Institute, Cleveland, Ohio, USA
| | - Belinda B. Willard
- Proteomics and Metabolomics Core, Cleveland Clinic Lerner Research Institute, Cleveland, Ohio, USA
| | - Hudson H. Freeze
- Human Genetics Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Ping He
- Department of Biochemistry, Lake Erie College of Osteopathic Medicine, Erie, PA, USA,Correspondence: Department of Pre-Clinical Medicine, Lake Erie College of Osteopathic Medicine, 2000 West Grandview Boulevard, Room: 2-107, Erie, PA 16509, USA,
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10
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Checler F, Alves da Costa C. Parkin as a Molecular Bridge Linking Alzheimer’s and Parkinson’s Diseases? Biomolecules 2022; 12:biom12040559. [PMID: 35454148 PMCID: PMC9026546 DOI: 10.3390/biom12040559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 04/04/2022] [Accepted: 04/07/2022] [Indexed: 02/01/2023] Open
Abstract
Alzheimer’s (AD) and Parkinson’s (PD) diseases are two distinct age-related pathologies that are characterized by various common dysfunctions. They are referred to as proteinopathies characterized by ubiquitinated protein accumulation and aggregation. This accumulation is mainly due to altered lysosomal and proteasomal clearing processes and is generally accompanied by ER stress disturbance, autophagic and mitophagic defects, mitochondrial structure and function alterations and enhanced neuronal cell death. Genetic approaches aimed at identifying molecular triggers responsible for familial forms of AD or PD have helped to understand the etiology of their sporadic counterparts. It appears that several proteins thought to contribute to one of these pathologies are also likely to contribute to the other. One such protein is parkin (PK). Here, we will briefly describe anatomical lesions and genetic advances linked to AD and PD as well as the main cellular processes commonly affected in these pathologies. Further, we will focus on current studies suggesting that PK could well participate in AD and thereby act as a molecular bridge between these two pathologies. In particular, we will focus on the transcription factor function of PK and its newly described transcriptional targets that are directly related to AD- and PD-linked cellular defects.
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11
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Myers RR, Sanchez-Garcia J, Leving DC, Melvin RG, Fernandez-Funez P. New Drosophila models to uncover the intrinsic and extrinsic factors that mediate the toxicity of the human prion protein. Dis Model Mech 2022; 15:dmm049184. [PMID: 35142350 PMCID: PMC9093039 DOI: 10.1242/dmm.049184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2021] [Accepted: 02/01/2022] [Indexed: 11/20/2022] Open
Abstract
Misfolding of the prion protein (PrP) is responsible for devastating neurological disorders in humans and other mammals. An unresolved problem in the field is unraveling the mechanisms governing PrP conformational dynamics, misfolding, and the cellular mechanism leading to neurodegeneration. The variable susceptibility of mammals to prion diseases is a natural resource that can be exploited to understand the conformational dynamics of PrP. Here we present a new fly model expressing human PrP with new, robust phenotypes in brain neurons and the eye. By using comparable attP2 insertions, we demonstrated the heightened toxicity of human PrP compared to rodent PrP along with a specific interaction with the amyloid-β peptide. By using this new model, we started to uncover the intrinsic (sequence/structure) and extrinsic (interactions) factors regulating PrP toxicity. We described PERK (officially known as EIF2AK3 in humans) and activating transcription factor 4 (ATF4) as key in the cellular mechanism mediating the toxicity of human PrP and uncover a key new protective activity for 4E-BP (officially known as Thor in Drosophila and EIF4EBP2 in humans), an ATF4 transcriptional target. Lastly, mutations in human PrP (N159D, D167S, N174S) showed partial protective activity, revealing its high propensity to misfold into toxic conformations.
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Affiliation(s)
- Ryan R. Myers
- Department of Biomedical Sciences, University of Minnesota Medical School, Duluth Campus, Duluth, MN 55812, USA
| | | | - Daniel C. Leving
- Department of Biomedical Sciences, University of Minnesota Medical School, Duluth Campus, Duluth, MN 55812, USA
| | - Richard G. Melvin
- Department of Biomedical Sciences, University of Minnesota Medical School, Duluth Campus, Duluth, MN 55812, USA
| | - Pedro Fernandez-Funez
- Department of Biomedical Sciences, University of Minnesota Medical School, Duluth Campus, Duluth, MN 55812, USA
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12
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Gadhe L, Sakunthala A, Mukherjee S, Gahlot N, Bera R, Sawner AS, Kadu P, Maji SK. Intermediates of α-synuclein aggregation: Implications in Parkinson's disease pathogenesis. Biophys Chem 2021; 281:106736. [PMID: 34923391 DOI: 10.1016/j.bpc.2021.106736] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 11/27/2021] [Accepted: 11/27/2021] [Indexed: 12/11/2022]
Abstract
Cytoplasmic deposition of aberrantly misfolded α-synuclein (α-Syn) is a common feature of synucleinopathies, including Parkinson's disease (PD). However, the precise pathogenic mechanism of α-Syn in synucleinopathies remains elusive. Emerging evidence has suggested that α-Syn may contribute to PD pathogenesis in several ways; wherein the contribution of fibrillar species, for exerting toxicity and disease transmission, cannot be neglected. Further, the oligomeric species could be the most plausible neurotoxic species causing neuronal cell death. However, understanding the structural and molecular insights of these oligomers are very challenging due to the heterogeneity and transient nature of the species. In this review, we discuss the recent advancements in understanding the formation and role of α-Syn oligomers in PD pathogenesis. We also summarize the different types of α-Syn oligomeric species and potential mechanisms to exert neurotoxicity. Finally, we address the possible ways to target α-Syn as a promising approach against PD and the possible future directions.
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Affiliation(s)
- Laxmikant Gadhe
- Department of Biosciences and Bioengineering, IIT Bombay, Powai, Mumbai 400076, India
| | - Arunima Sakunthala
- Department of Biosciences and Bioengineering, IIT Bombay, Powai, Mumbai 400076, India
| | - Semanti Mukherjee
- Department of Biosciences and Bioengineering, IIT Bombay, Powai, Mumbai 400076, India
| | - Nitisha Gahlot
- Department of Biosciences and Bioengineering, IIT Bombay, Powai, Mumbai 400076, India
| | - Riya Bera
- Department of Biosciences and Bioengineering, IIT Bombay, Powai, Mumbai 400076, India
| | - Ajay Singh Sawner
- Department of Biosciences and Bioengineering, IIT Bombay, Powai, Mumbai 400076, India
| | - Pradeep Kadu
- Department of Biosciences and Bioengineering, IIT Bombay, Powai, Mumbai 400076, India
| | - Samir K Maji
- Department of Biosciences and Bioengineering, IIT Bombay, Powai, Mumbai 400076, India.
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13
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Wang C, Yang T, Liang M, Xie J, Song N. Astrocyte dysfunction in Parkinson's disease: from the perspectives of transmitted α-synuclein and genetic modulation. Transl Neurodegener 2021; 10:39. [PMID: 34657636 PMCID: PMC8522040 DOI: 10.1186/s40035-021-00265-y] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Accepted: 10/05/2021] [Indexed: 01/20/2023] Open
Abstract
Parkinson's disease (PD) is a common neurodegenerative disorder that primarily affects the elderly. While the etiology of PD is likely multifactorial with the involvement of genetic, environmental, aging and other factors, α-synuclein (α-syn) pathology is a pivotal mechanism underlying the development of PD. In recent years, astrocytes have attracted considerable attention in the field. Although astrocytes perform a variety of physiological functions in the brain, they are pivotal mediators of α-syn toxicity since they internalize α-syn released from damaged neurons, and this triggers an inflammatory response, protein degradation dysfunction, mitochondrial dysfunction and endoplasmic reticulum stress. Astrocytes are indispensable coordinators in the background of several genetic mutations, including PARK7, GBA1, LRRK2, ATP13A2, PINK1, PRKN and PLA2G6. As the most abundant glial cells in the brain, functional astrocytes can be replenished and even converted to functional neurons. In this review, we discuss astrocyte dysfunction in PD with an emphasis on α-syn toxicity and genetic modulation and conclude that astrocyte replenishment is a valuable therapeutic approach in PD.
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Affiliation(s)
- Changjing Wang
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders, School of Basic Medicine, Qingdao University, Qingdao, 266071, China
| | - Tongtong Yang
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders, School of Basic Medicine, Qingdao University, Qingdao, 266071, China
| | - Meiyu Liang
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders, School of Basic Medicine, Qingdao University, Qingdao, 266071, China
| | - Junxia Xie
- Institute of Brain Science and Disease, Qingdao University, Qingdao, 266071, China.
| | - Ning Song
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders, School of Basic Medicine, Qingdao University, Qingdao, 266071, China.
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14
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Manzanza NDO, Sedlackova L, Kalaria RN. Alpha-Synuclein Post-translational Modifications: Implications for Pathogenesis of Lewy Body Disorders. Front Aging Neurosci 2021; 13:690293. [PMID: 34248606 PMCID: PMC8267936 DOI: 10.3389/fnagi.2021.690293] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 05/24/2021] [Indexed: 12/16/2022] Open
Abstract
Lewy Body Disorders (LBDs) lie within the spectrum of age-related neurodegenerative diseases now frequently categorized as the synucleinopathies. LBDs are considered to be among the second most common form of neurodegenerative dementias after Alzheimer's disease. They are progressive conditions with variable clinical symptoms embodied within specific cognitive and behavioral disorders. There are currently no effective treatments for LBDs. LBDs are histopathologically characterized by the presence of abnormal neuronal inclusions commonly known as Lewy Bodies (LBs) and extracellular Lewy Neurites (LNs). The inclusions predominantly comprise aggregates of alpha-synuclein (aSyn). It has been proposed that post-translational modifications (PTMs) such as aSyn phosphorylation, ubiquitination SUMOylation, Nitration, o-GlcNacylation, and Truncation play important roles in the formation of toxic forms of the protein, which consequently facilitates the formation of these inclusions. This review focuses on the role of different PTMs in aSyn in the pathogenesis of LBDs. We highlight how these PTMs interact with aSyn to promote misfolding and aggregation and interplay with cell membranes leading to the potential functional and pathogenic consequences detected so far, and their involvement in the development of LBDs.
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Affiliation(s)
- Nelson de Oliveira Manzanza
- Translational and Clinical Research Institute, Campus for Ageing and Vitality, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Lucia Sedlackova
- Biosciences Institute, Campus for Ageing and Vitality, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Raj N. Kalaria
- Translational and Clinical Research Institute, Campus for Ageing and Vitality, Newcastle University, Newcastle upon Tyne, United Kingdom
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15
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Ren H, Zhai W, Lu X, Wang G. The Cross-Links of Endoplasmic Reticulum Stress, Autophagy, and Neurodegeneration in Parkinson's Disease. Front Aging Neurosci 2021; 13:691881. [PMID: 34168552 PMCID: PMC8218021 DOI: 10.3389/fnagi.2021.691881] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Accepted: 05/10/2021] [Indexed: 12/17/2022] Open
Abstract
Parkinson’s disease (PD) is the most common neurodegenerative movement disorder, and it is characterized by the selective loss of dopaminergic (DA) neurons in the substantia nigra pars compacta (SNpc), as well as the presence of intracellular inclusions with α-synuclein as the main component in surviving DA neurons. Emerging evidence suggests that the imbalance of proteostasis is a key pathogenic factor for PD. Endoplasmic reticulum (ER) stress-induced unfolded protein response (UPR) and autophagy, two major pathways for maintaining proteostasis, play important roles in PD pathology and are considered as attractive therapeutic targets for PD treatment. However, although ER stress/UPR and autophagy appear to be independent cellular processes, they are closely related to each other. In this review, we focused on the roles and molecular cross-links between ER stress/UPR and autophagy in PD pathology. We systematically reviewed and summarized the most recent advances in regulation of ER stress/UPR and autophagy, and their cross-linking mechanisms. We also reviewed and discussed the mechanisms of the coexisting ER stress/UPR activation and dysregulated autophagy in the lesion regions of PD patients, and the underlying roles and molecular crosslinks between ER stress/UPR activation and the dysregulated autophagy in DA neurodegeneration induced by PD-associated genetic factors and PD-related neurotoxins. Finally, we indicate that the combined regulation of ER stress/UPR and autophagy would be a more effective treatment for PD rather than regulating one of these conditions alone.
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Affiliation(s)
- Haigang Ren
- Department of Neurology, Center of Translational Medicine, Taicang Affiliated Hospital of Soochow University, The First People's Hospital of Taicang, Suzhou, China.,Jiangsu Key Laboratory of Translational Research and Therapy for Neuropsychiatric Disorders, Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou, China
| | - Wanqing Zhai
- Department of Neurology, Center of Translational Medicine, Taicang Affiliated Hospital of Soochow University, The First People's Hospital of Taicang, Suzhou, China
| | - Xiaojun Lu
- Department of Neurology, Center of Translational Medicine, Taicang Affiliated Hospital of Soochow University, The First People's Hospital of Taicang, Suzhou, China
| | - Guanghui Wang
- Department of Neurology, Center of Translational Medicine, Taicang Affiliated Hospital of Soochow University, The First People's Hospital of Taicang, Suzhou, China.,Jiangsu Key Laboratory of Translational Research and Therapy for Neuropsychiatric Disorders, Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou, China
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16
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da Costa CA, Manaa WE, Duplan E, Checler F. The Endoplasmic Reticulum Stress/Unfolded Protein Response and Their Contributions to Parkinson's Disease Physiopathology. Cells 2020; 9:cells9112495. [PMID: 33212954 PMCID: PMC7698446 DOI: 10.3390/cells9112495] [Citation(s) in RCA: 52] [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: 10/23/2020] [Revised: 11/13/2020] [Accepted: 11/16/2020] [Indexed: 12/11/2022] Open
Abstract
Parkinson’s disease (PD) is a multifactorial age-related movement disorder in which defects of both mitochondria and the endoplasmic reticulum (ER) have been reported. The unfolded protein response (UPR) has emerged as a key cellular dysfunction associated with the etiology of the disease. The UPR involves a coordinated response initiated in the endoplasmic reticulum that grants the correct folding of proteins. This review gives insights on the ER and its functioning; the UPR signaling cascades; and the link between ER stress, UPR activation, and physiopathology of PD. Thus, post-mortem studies and data obtained by either in vitro and in vivo pharmacological approaches or by genetic modulation of PD causative genes are described. Further, we discuss the relevance and impact of the UPR to sporadic and genetic PD pathology.
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17
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Du XY, Xie XX, Liu RT. The Role of α-Synuclein Oligomers in Parkinson's Disease. Int J Mol Sci 2020; 21:ijms21228645. [PMID: 33212758 PMCID: PMC7697105 DOI: 10.3390/ijms21228645] [Citation(s) in RCA: 103] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Revised: 11/06/2020] [Accepted: 11/09/2020] [Indexed: 12/11/2022] Open
Abstract
α-synuclein (α-syn) is a protein associated with the pathogenesis of Parkinson’s disease (PD), the second most common neurodegeneration disease with no effective treatment. However, how α-syn drives the pathology of PD remains elusive. Recent studies suggest that α-syn oligomers are the primary cause of neurotoxicity and play a critical role in PD. In this review, we discuss the process of α-syn oligomers formation and the current understanding of the structures of oligomers. We also describe seed and propagation effects of oligomeric forms of α-syn. Then, we summarize the mechanism by which α-syn oligomers exert neurotoxicity and promote neurodegeneration, including mitochondrial dysfunction, endoplasmic reticulum stress, proteostasis dysregulation, synaptic impairment, cell apoptosis and neuroinflammation. Finally, we investigate treatment regimens targeting α-syn oligomers at present. Further research is needed to understand the structure and toxicity mechanism of different types of oligomers, so as to provide theoretical basis for the treatment of PD.
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Affiliation(s)
- Xiao-yu Du
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Haidian District, Beijing 100190, China; (X.-y.D.); (X.-x.X.)
- School of Chemical Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xi-xiu Xie
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Haidian District, Beijing 100190, China; (X.-y.D.); (X.-x.X.)
| | - Rui-tian Liu
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Haidian District, Beijing 100190, China; (X.-y.D.); (X.-x.X.)
- Correspondence: ; Tel.: +86-10-82545017
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18
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Uddin MS, Tewari D, Sharma G, Kabir MT, Barreto GE, Bin-Jumah MN, Perveen A, Abdel-Daim MM, Ashraf GM. Molecular Mechanisms of ER Stress and UPR in the Pathogenesis of Alzheimer's Disease. Mol Neurobiol 2020; 57:2902-2919. [PMID: 32430843 DOI: 10.1007/s12035-020-01929-y] [Citation(s) in RCA: 87] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2020] [Accepted: 05/01/2020] [Indexed: 01/01/2023]
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disease involving aggregation of misfolded proteins inside the neuron causing prolonged cellular stress. The neuropathological hallmarks of AD include the formation of senile plaques and neurofibrillary tangles in specific brain regions that lead to synaptic loss and neuronal death. The exact mechanism of neuron dysfunction in AD remains obscure. In recent years, endoplasmic reticulum (ER) dysfunction has been implicated in neuronal degeneration seen in AD. Apart from AD, many other diseases also involve misfolded proteins aggregations in the ER, a condition referred to as ER stress. The response of the cell to ER stress is to activate a group of signaling pathways called unfolded protein response (UPR) that stimulates a particular transcriptional program to restore ER function and ensure cell survival. ER stress also involves the generation of reactive oxygen species (ROS) that, together with mitochondrial ROS and decreased effectiveness of antioxidant mechanisms, producing a condition of chronic oxidative stress. The unfolded proteins may not always produce a response that leads to the restoration of cellular functions, but they may also lead to inflammation by a set of different pathways with deleterious consequences. In this review, we extensively discuss the role of ER stress and how to target it using different pharmacological approaches in AD development and onset.
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Affiliation(s)
- Md Sahab Uddin
- Department of Pharmacy, Southeast University, Dhaka, Bangladesh.
- Pharmakon Neuroscience Research Network, Dhaka, Bangladesh.
| | - Devesh Tewari
- Department of Pharmacognosy, School of Pharmaceutical Sciences, Lovely Professional University, Phagwara, Punjab, India
| | - Gaurav Sharma
- Department of Physiology, AIIMS Jodhpur, Jodhpur, India
| | | | - George E Barreto
- Department of Biological Sciences, University of Limerick, Limerick, Ireland.
- Instituto de Ciencias Biomédicas, Universidad Autónoma de Chile, Santiago, Chile.
| | - May N Bin-Jumah
- Department of Biology, College of Science, Princess Nourah bint Abdulrahman University, Riyadh 11474, Saudi Arabia
| | - Asma Perveen
- Glocal School of Life Sciences, Glocal University, Saharanpur, India
| | - Mohamed M Abdel-Daim
- Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia
- Pharmacology Department, Faculty of Veterinary Medicine, Suez Canal University, Ismailia 41522, Egypt
| | - Ghulam Md Ashraf
- King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia.
- Department of Medical Laboratory Technology, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia.
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19
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Mou Z, Yuan YH, Zhang Z, Song LK, Chen NH. Endoplasmic reticulum stress, an important factor in the development of Parkinson’s disease. Toxicol Lett 2020; 324:20-29. [DOI: 10.1016/j.toxlet.2020.01.019] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 01/22/2020] [Accepted: 01/23/2020] [Indexed: 02/07/2023]
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20
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Vaikath NN, Hmila I, Gupta V, Erskine D, Ingelsson M, El-Agnaf OMA. Antibodies against alpha-synuclein: tools and therapies. J Neurochem 2019; 150:612-625. [PMID: 31055836 DOI: 10.1111/jnc.14713] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2019] [Revised: 04/20/2019] [Accepted: 04/24/2019] [Indexed: 01/04/2023]
Abstract
Synucleinopathies including Parkinson's disease, dementia with Lewy bodies and multiple system atrophy are characterized by the abnormal accumulation and propagation of α-synuclein (α-syn) pathology in the central and peripheral nervous system as Lewy bodies or glial cytoplasmic inclusions. Several antibodies against α-syn have been developed since it was first detected as the major component of Lewy bodies and glial cytoplasmic inclusions. Over the years, researchers have generated specific antibodies that alleviate the accumulation of intracellular aggregated α-syn and associated pathology in cellular and preclinical models of synucleinopathies. So far, antibodies have been the first choice as tools for research and diagnosis and currently, a wide variety of antibody fragments have been developed as an alternative to full-length antibodies for increasing its therapeutic usefulness. Recently, conformation specific antibody-based approaches have been found to be promising as therapeutic strategies, both to block α-syn aggregation and ameliorate the resultant cytotoxicity, and as diagnostic tools. In this review, we summarize different α-syn specific antibodies and provide their usefulness in tackling synucleinopathies. This article is part of the Special Issue "Synuclein".
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Affiliation(s)
- Nishant N Vaikath
- Neurological Disorder Research Center, Qatar Biomedical Research Institute (QBRI), Hamad Bin Khalifa University (HBKU), Qatar Foundation, Doha, Qatar
| | - Issam Hmila
- Neurological Disorder Research Center, Qatar Biomedical Research Institute (QBRI), Hamad Bin Khalifa University (HBKU), Qatar Foundation, Doha, Qatar
| | - Vijay Gupta
- Neurological Disorder Research Center, Qatar Biomedical Research Institute (QBRI), Hamad Bin Khalifa University (HBKU), Qatar Foundation, Doha, Qatar
| | - Daniel Erskine
- Institute of Neuroscience, Campus for Ageing and Vitality, Newcastle University, Newcastle upon Tyne, UK
| | - Martin Ingelsson
- Department of Public Health/Geriatrics, Uppsala University, Uppsala, Sweden
| | - Omar M A El-Agnaf
- Neurological Disorder Research Center, Qatar Biomedical Research Institute (QBRI), Hamad Bin Khalifa University (HBKU), Qatar Foundation, Doha, Qatar
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21
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Zhang J, Li X, Li JD. The Roles of Post-translational Modifications on α-Synuclein in the Pathogenesis of Parkinson's Diseases. Front Neurosci 2019; 13:381. [PMID: 31057362 PMCID: PMC6482271 DOI: 10.3389/fnins.2019.00381] [Citation(s) in RCA: 127] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Accepted: 04/02/2019] [Indexed: 12/15/2022] Open
Abstract
Parkinson’s disease is the second most common neurodegenerative disorder. Although the pathogenesis of Parkinson’s disease is not entirely clear, the aberrant aggregation of α-synuclein has long been considered as an important risk factor. Elucidating the mechanisms that influence the aggregation of α-synuclein is essential for developing an effective diagnostic, preventative and therapeutic strategy to treat this devastating disease. The aggregation of α-synuclein is influenced by several post-translational modifications. Here, we summarized the major post-translational modifications (phosphorylation, ubiquitination, truncation, nitration, O-GlcNAcylation) of α-synuclein and the effect of these modifications on α-synuclein aggregation, which may provide potential targets for future therapeutics.
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Affiliation(s)
- Jiaming Zhang
- Center for Reproductive Medicine, The First Affiliated Hospital, University of South China, Hengyang, China
| | - Xiaoping Li
- Center for Reproductive Medicine, The First Affiliated Hospital, University of South China, Hengyang, China
| | - Jia-Da Li
- Hunan Key Laboratory of Animal Models for Human Diseases, School of Life Sciences, Central South University, Changsha, China.,Hunan Key Laboratory of Medical Genetics, Center for Medical Genetics, Central South University, Changsha, China
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22
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Hashimoto S, Saido TC. Critical review: involvement of endoplasmic reticulum stress in the aetiology of Alzheimer's disease. Open Biol 2019; 8:rsob.180024. [PMID: 29695619 PMCID: PMC5936719 DOI: 10.1098/rsob.180024] [Citation(s) in RCA: 88] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 04/03/2018] [Indexed: 12/18/2022] Open
Abstract
The endoplasmic reticulum (ER) stress response is regarded as an important process in the aetiology of Alzheimer's disease (AD). The accumulation of pathogenic misfolded proteins and the disruption of intracellular calcium (Ca2+) signalling are considered to be fundamental mechanisms that underlie the induction of ER stress, leading to neuronal cell death. Indeed, a number of studies have proposed molecular mechanisms linking ER stress to AD pathogenesis based on results from in vitro systems and AD mouse models. However, stress responsivity was largely different between each mouse model, even though all of these models display AD-related pathologies. While several reports have shown elevated ER stress responses in amyloid precursor protein (APP) and presenilin 1 (PS1) double-transgenic (Tg) AD mouse models, we and other groups, in contrast, observed no such ER stress response in APP-single-Tg or App-knockin mice. Therefore, it is debatable whether the ER stress observed in APP and PS1 double-Tg mice is due to AD pathology. From these findings, the roles of ER stress in AD pathogenesis needs to be carefully addressed in future studies. In this review, we summarize research detailing the relationship between ER stress and AD, and analyse the results in detail.
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Affiliation(s)
- Shoko Hashimoto
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Takaomi C Saido
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
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23
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Heman-Ackah SM, Manzano R, Hoozemans JJM, Scheper W, Flynn R, Haerty W, Cowley SA, Bassett AR, Wood MJA. Alpha-synuclein induces the unfolded protein response in Parkinson's disease SNCA triplication iPSC-derived neurons. Hum Mol Genet 2018; 26:4441-4450. [PMID: 28973645 DOI: 10.1093/hmg/ddx331] [Citation(s) in RCA: 110] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Accepted: 08/17/2017] [Indexed: 11/13/2022] Open
Abstract
The recent generation of induced pluripotent stem cells (iPSCs) from a patient with Parkinson's disease (PD) resulting from triplication of the α-synuclein (SNCA) gene locus allows unprecedented opportunities to explore its contribution to the molecular pathogenesis of PD. We used the double-nicking CRISPR/Cas9 system to conduct site-specific mutagenesis of SNCA in these cells, generating an isogenic iPSC line with normalized SNCA gene dosage. Comparative gene expression analysis of neuronal derivatives from these iPSCs revealed an ER stress phenotype, marked by induction of the IRE1α/XBP1 axis of the unfolded protein response (UPR) and culminating in terminal UPR activation. Neuropathological analysis of post-mortem brain tissue demonstrated that pIRE1α is expressed in PD brains within neurons containing elevated levels of α-synuclein or Lewy bodies. Having used this pair of isogenic iPSCs to define this phenotype, these cells can be further applied in UPR-targeted drug discovery towards the development of disease-modifying therapeutics.
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Affiliation(s)
- Sabrina M Heman-Ackah
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QX, UK.,NIH Oxford-Cambridge Scholars Program, National Institutes of Health, Bethesda, MD 20892, USA.,UNC MD-PhD Program, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Raquel Manzano
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QX, UK
| | | | - Wiep Scheper
- Department of Clinical Genetics and Alzheimer Center, VU University Medical Center, 1007 MB Amsterdam, The Netherlands.,Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, VU University, 1081 HV Amsterdam, The Netherlands
| | - Rowan Flynn
- James Martin Stem Cell Facility, Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK
| | - Wilfried Haerty
- Earlham Institute, Norwich Research Park, Norwich NR4 7UH, UK
| | - Sally A Cowley
- James Martin Stem Cell Facility, Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK
| | - Andrew R Bassett
- Genome Engineering Oxford, Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK
| | - Matthew J A Wood
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3QX, UK
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24
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Alzheimer's disease pathology and the unfolded protein response: prospective pathways and therapeutic targets. Behav Pharmacol 2018; 28:161-178. [PMID: 28252521 DOI: 10.1097/fbp.0000000000000299] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Many vital interdependent cellular functions including proteostasis, lipogenesis and Ca homeostasis are executed by the endoplasmic reticulum (ER). Exogenous insults can impair ER performance: this must be rapidly corrected or cell death will ensue. Protective adaptations can boost the functional capacity of the ER and form the basis of the unfolded protein response (UPR). Activated in response to the accumulation of misfolded proteins, the UPR can halt protein translation while increasing protein-handling chaperones and the degradation of erroneous proteins through a conserved three-tier molecular cascade. However, prolonged activation of the UPR can result in the maladaptation of the system, resulting in the activation of inflammatory and apoptotic effectors. Recently, UPR and its involvement in neurodegenerative disease has attracted much interest and numerous potentially 'drugable' points of crosstalk are now emerging. Here, we summarize the functions of the ER and UPR, and highlight evidence for its potential role in the pathogenesis of Alzheimer's disease, before discussing several key targets with therapeutic potential.
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25
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Bengoa-Vergniory N, Roberts RF, Wade-Martins R, Alegre-Abarrategui J. Alpha-synuclein oligomers: a new hope. Acta Neuropathol 2017; 134:819-838. [PMID: 28803412 PMCID: PMC5663814 DOI: 10.1007/s00401-017-1755-1] [Citation(s) in RCA: 220] [Impact Index Per Article: 31.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Revised: 07/21/2017] [Accepted: 07/22/2017] [Indexed: 01/22/2023]
Abstract
Alpha-synuclein is a protein implicated in Parkinson’s disease and thought to be one of the main pathological drivers in the disease, although it remains unclear how this protein elicits its neurotoxic effects. Recent findings indicate that the assembly of toxic oligomeric species of alpha-synuclein may be one of the key processes for the pathology and spread of the disease. The absence of a sensitive in situ detection method has hindered the study of these oligomeric species and the role they play in the human brain until recently. In this review, we assess the evidence for the toxicity and prion-like activity of oligomeric forms of alpha-synuclein and discuss the advances in our understanding of the role of alpha-synuclein in Parkinson’s disease that may be brought about by the specific and sensitive detection of distinct oligomeric species in post-mortem patient brain. Finally, we discuss current approaches being taken to therapeutically target alpha-synuclein oligomers and their implications.
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Affiliation(s)
- Nora Bengoa-Vergniory
- Department of Physiology, Anatomy and Genetics, Oxford Parkinson's Disease Centre, University of Oxford, South Parks Road, Oxford, OX1 3QT, UK
| | - Rosalind F Roberts
- Montreal Neurological Institute, McGill University, 3801 Rue University, Montreal, QC, H3A 2B4, Canada
| | - Richard Wade-Martins
- Department of Physiology, Anatomy and Genetics, Oxford Parkinson's Disease Centre, University of Oxford, South Parks Road, Oxford, OX1 3QT, UK.
| | - Javier Alegre-Abarrategui
- Department of Physiology, Anatomy and Genetics, Oxford Parkinson's Disease Centre, University of Oxford, South Parks Road, Oxford, OX1 3QT, UK.
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26
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Kishino A, Hayashi K, Hidai C, Masuda T, Nomura Y, Oshima T. XBP1-FoxO1 interaction regulates ER stress-induced autophagy in auditory cells. Sci Rep 2017; 7:4442. [PMID: 28667325 PMCID: PMC5493624 DOI: 10.1038/s41598-017-02960-1] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Accepted: 04/21/2017] [Indexed: 01/07/2023] Open
Abstract
The purpose of this study was to clarify the relationship among X-box-binding protein 1 unspliced, spliced (XBP1u, s), Forkhead box O1 (FoxO1) and autophagy in the auditory cells under endoplasmic reticulum (ER) stress. In addition, the relationship between ER stress that causes unfolded protein response (UPR) and autophagy was also investigated. The present study reported ER stress induction by tunicamycin treatment that resulted in IRE1α-mediated XBP1 mRNA splicing and autophagy. XBP1 mRNA splicing and FoxO1 were found to be involved in ER stress-induced autophagy. This inference was based on the observation that the expression of LC3-II was suppressed by knockdown of IRE1α, XBP1 or FoxO1. In addition, XBP1u was found to interact with XBP1s in auditory cells under ER stress, functioning as a negative feedback regulator that was based on two important findings. Firstly, there was a significant inverse correlation between XBP1u and XBP1s expressions, and secondly, the expression of XBP1 protein showed different dynamics compared to the XBP1 mRNA level. Furthermore, our results regarding the relationship between XBP1 and FoxO1 by small interfering RNA (siRNA) paradoxically showed negative regulation of FoxO1 expression by XBP1. Our findings revealed that the XBP1-FoxO1 interaction regulated the ER stress-induced autophagy in auditory cells.
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Affiliation(s)
- Akihiro Kishino
- Department of Otolaryngology, School of Medicine, Nihon University, Tokyo, 173-8610, Japan
| | - Ken Hayashi
- Department of Otolaryngology, Kamio Memorial Hospital, Tokyo, 101-0063, Japan
| | - Chiaki Hidai
- Department of Physiology, School of Medicine, Nihon University, Tokyo, 173-8610, Japan
| | - Takeshi Masuda
- Department of Otolaryngology, School of Medicine, Nihon University, Tokyo, 173-8610, Japan
| | - Yasuyuki Nomura
- Department of Otolaryngology, School of Medicine, Nihon University, Tokyo, 173-8610, Japan
| | - Takeshi Oshima
- Department of Otolaryngology, School of Medicine, Nihon University, Tokyo, 173-8610, Japan.
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Cissé M, Duplan E, Checler F. The transcription factor XBP1 in memory and cognition: Implications in Alzheimer disease. Mol Med 2017; 22:905-917. [PMID: 28079229 DOI: 10.2119/molmed.2016.00229] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Accepted: 12/23/2016] [Indexed: 12/21/2022] Open
Abstract
X-box binding protein 1 (XBP1) is a unique basic region leucine zipper transcription factor isolated two decades ago in a search for regulators of major histocompatibility complex class II gene expression. XBP1 is a very complex protein regulating many physiological functions, including immune system, inflammatory responses, and lipid metabolism. Evidence over the past few years suggests that XBP1 also plays important roles in pathological settings since its activity as transcription factor has profound effects on the prognosis and progression of diseases such as cancer, neurodegeneration, and diabetes. Here we provide an overview on recent advances in our understanding of this multifaceted molecule, particularly in regulating synaptic plasticity and memory function, and the implications in neurodegenerative diseases with emphasis on Alzheimer disease.
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Affiliation(s)
- Moustapha Cissé
- Université Côte d'Azur, INSERM, CNRS, IPMC, team labeled "Fondation pour la Recherche Médicale" and "Laboratory of Excellence (LABEX) Distalz", 660 route des Lucioles, 06560, Sophia-Antipolis, Valbonne, France
| | - Eric Duplan
- Université Côte d'Azur, INSERM, CNRS, IPMC, team labeled "Fondation pour la Recherche Médicale" and "Laboratory of Excellence (LABEX) Distalz", 660 route des Lucioles, 06560, Sophia-Antipolis, Valbonne, France
| | - Frédéric Checler
- Université Côte d'Azur, INSERM, CNRS, IPMC, team labeled "Fondation pour la Recherche Médicale" and "Laboratory of Excellence (LABEX) Distalz", 660 route des Lucioles, 06560, Sophia-Antipolis, Valbonne, France
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Cabral-Miranda F, Hetz C. ER Stress and Neurodegenerative Disease: A Cause or Effect Relationship? Curr Top Microbiol Immunol 2017; 414:131-157. [PMID: 28864830 DOI: 10.1007/82_2017_52] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The accumulation of protein aggregates has a fundamental role in the patophysiology of distinct neurodegenerative diseases. This phenomenon may have a common origin, where disruption of intracellular mechanisms related to protein homeostasis (here termed proteostasis) control during aging may result in abnormal protein aggregation. The unfolded protein response (UPR) embodies a major element of the proteostasis network triggered by endoplasmic reticulum (ER) stress. Chronic ER stress may operate as possible mechanism of neurodegenerative and synaptic dysfunction, and in addition contribute to the abnormal aggregation of key disease-related proteins. In this article we overview the most recent findings suggesting a causal role of ER stress in neurodegenerative diseases.
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Affiliation(s)
- Felipe Cabral-Miranda
- Faculty of Medicine, Biomedical Neuroscience Institute, University of Chile, Santiago, Chile.,Faculty of Medicine, Center for Geroscience, Brain Health and Metabolism, University of Chile, Santiago, Chile.,Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, University of Chile, Independencia 1027, P.O.BOX 70086, Santiago, Chile.,Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Claudio Hetz
- Faculty of Medicine, Biomedical Neuroscience Institute, University of Chile, Santiago, Chile. .,Faculty of Medicine, Center for Geroscience, Brain Health and Metabolism, University of Chile, Santiago, Chile. .,Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, University of Chile, Independencia 1027, P.O.BOX 70086, Santiago, Chile. .,Buck Institute for Research on Aging, Novato, CA, 94945, USA. .,Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, MA, 02115, USA.
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van Diggelen F, Tepper AWJW, Apetri MM, Otzen DE. α-Synuclein Oligomers: A Study in Diversity. Isr J Chem 2016. [DOI: 10.1002/ijch.201600116] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Femke van Diggelen
- Crossbeta Biosciences; Padualaan 8 3584CH Utrecht The Netherlands
- Interdisciplinary Nanoscience Centre (iNANO); Aarhus University; Gustav Wieds Vej 14 8000C Aarhus Denmark
| | | | | | - Daniel E. Otzen
- Interdisciplinary Nanoscience Centre (iNANO); Aarhus University; Gustav Wieds Vej 14 8000C Aarhus Denmark
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30
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Bell MC, Meier SE, Ingram AL, Abisambra JF. PERK-opathies: An Endoplasmic Reticulum Stress Mechanism Underlying Neurodegeneration. Curr Alzheimer Res 2016; 13:150-63. [PMID: 26679859 PMCID: PMC6542591 DOI: 10.2174/1567205013666151218145431] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Revised: 08/14/2015] [Accepted: 08/18/2015] [Indexed: 11/22/2022]
Abstract
The unfolded protein response (UPR) plays a vital role in maintaining cell homeostasis as a consequence of endoplasmic reticulum (ER) stress. However, prolonged UPR activity leads to cell death. This time-dependent dual functionality of the UPR represents the adaptive and cytotoxic pathways that result from ER stress. Chronic UPR activation in systemic and neurodegenerative diseases has been identified as an early sign of cellular dyshomeostasis. The Protein Kinase R-like ER Kinase (PERK) pathway is one of three major branches in the UPR, and it is the only one to modulate protein synthesis as an adaptive response. The specific identification of prolonged PERK activity has been correlated with the progression of disorders such as diabetes, Alzheimer's disease, and cancer, suggesting that PERK plays a role in the pathology of these disorders. For the first time, the term "PERK-opathies" is used to group these diseases in which PERK mediates detriment to the cell culminating in chronic disorders. This article reviews the literature documenting links between systemic disorders with the UPR, but with a specific emphasis on the PERK pathway. Then, articles reporting links between the UPR, and more specifically PERK, and neurodegenerative disorders are presented. Finally, a therapeutic perspective is discussed, where PERK interventions could be potential remedies for cellular dysfunction in chronic neurodegenerative disorders.
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Affiliation(s)
| | | | | | - Jose F Abisambra
- Sanders-Brown Center on Aging and Department of Physiology, College of Medicine, University of Kentucky, 800 S Limestone Street, Lexington, KY 40536-0230, USA.
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31
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Villar-Piqué A, Lopes da Fonseca T, Outeiro TF. Structure, function and toxicity of alpha-synuclein: the Bermuda triangle in synucleinopathies. J Neurochem 2015; 139 Suppl 1:240-255. [PMID: 26190401 DOI: 10.1111/jnc.13249] [Citation(s) in RCA: 152] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 06/29/2015] [Accepted: 07/14/2015] [Indexed: 12/11/2022]
Abstract
Parkinson's disease belongs to a group of currently incurable neurodegenerative disorders characterized by the misfolding and accumulation of alpha-synuclein aggregates that are commonly known as synucleinopathies. Clinically, synucleinopathies are heterogeneous, reflecting the somewhat selective neuronal vulnerability characteristic of each disease. The precise molecular underpinnings of synucleinopathies remain unclear, but the process of aggregation of alpha-synuclein appears as a central event. However, there is still no consensus with respect to the toxic forms of alpha-synuclein, hampering our ability to use the protein as a target for therapeutic intervention. To decipher the molecular bases of synucleinopathies, it is essential to understand the complex triangle formed between the structure, function and toxicity of alpha-synuclein. Recently, important steps have been undertaken to elucidate the role of the protein in both physiological and pathological conditions. Here, we provide an overview of recent findings in the field of alpha-synuclein research, and put forward a new perspective over paradigms that persist in the field. Establishing whether alpha-synuclein has a causative role in all synucleinopathies will enable the identification of targets for the development of novel therapeutic strategies for this devastating group of disorders. Alpha-synuclein is the speculated cornerstone of several neurodegenerative disorders known as Synucleinopathies. Nevertheless, the mechanisms underlying the pathogenic effects of this protein remain unknown. Here, we review the recent findings in the three corners of alpha-synuclein biology - structure, function and toxicity - and discuss the enigmatic roads that have accompanied alpha-synuclein from the beginning. This article is part of a special issue on Parkinson disease.
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Affiliation(s)
- Anna Villar-Piqué
- Department of NeuroDegeneration and Restorative Research, Center for Nanoscale Microscopy and Molecular Physiology of the Brain, University Medical Center Göttingen, Göttingen, Germany
| | - Tomás Lopes da Fonseca
- Department of NeuroDegeneration and Restorative Research, Center for Nanoscale Microscopy and Molecular Physiology of the Brain, University Medical Center Göttingen, Göttingen, Germany.,Instituto de Fisiologia, Faculty of Medicine, University of Lisbon, Lisboa, Portugal
| | - Tiago Fleming Outeiro
- Department of NeuroDegeneration and Restorative Research, Center for Nanoscale Microscopy and Molecular Physiology of the Brain, University Medical Center Göttingen, Göttingen, Germany. .,Instituto de Fisiologia, Faculty of Medicine, University of Lisbon, Lisboa, Portugal. .,CEDOC, Faculdade de Ciências Médicas, Universidade Nova de Lisboa, Lisboa, Portugal.
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Roberts HL, Brown DR. Seeking a mechanism for the toxicity of oligomeric α-synuclein. Biomolecules 2015; 5:282-305. [PMID: 25816357 PMCID: PMC4496673 DOI: 10.3390/biom5020282] [Citation(s) in RCA: 142] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Revised: 03/08/2015] [Accepted: 03/11/2015] [Indexed: 12/31/2022] Open
Abstract
In a number of neurological diseases including Parkinson’s disease (PD), α‑synuclein is aberrantly folded, forming abnormal oligomers, and amyloid fibrils within nerve cells. Strong evidence exists for the toxicity of increased production and aggregation of α-synuclein in vivo. The toxicity of α-synuclein is popularly attributed to the formation of “toxic oligomers”: a heterogenous and poorly characterized group of conformers that may share common molecular features. This review presents the available evidence on the properties of α-synuclein oligomers and the potential molecular mechanisms of their cellular disruption. Toxic α-synuclein oligomers may impact cells in a number of ways, including the disruption of membranes, mitochondrial depolarization, cytoskeleton changes, impairment of protein clearance pathways, and enhanced oxidative stress. We also examine the relationship between α-synuclein toxic oligomers and amyloid fibrils, in the light of recent studies that paint a more complex picture of α-synuclein toxicity. Finally, methods of studying and manipulating oligomers within cells are described.
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Affiliation(s)
- Hazel L Roberts
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, UK.
| | - David R Brown
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, UK.
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33
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RTCB-1 mediates neuroprotection via XBP-1 mRNA splicing in the unfolded protein response pathway. J Neurosci 2015; 34:16076-85. [PMID: 25429148 DOI: 10.1523/jneurosci.1945-14.2014] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Parkinson's disease (PD), the second most prevalent neurodegenerative disorder, is characterized by the degeneration of dopamine (DA) neurons and age-dependent formation of protein inclusions that contain the α-synuclein (α-syn) protein. RNA interference (RNAi) screening using Caenorhabditis elegans identified RTCB-1, an uncharacterized gene product, as one of several significant modifiers of α-syn protein misfolding. RTCB-1 is the worm ortholog of the human HSPC117 protein, a component of RNA trafficking granules in mammalian neurons. Here we show that RTCB-1 protects C. elegans DA neurons from age-dependent degeneration induced by human α-syn. Moreover, neuronal-specific RNAi depletion of rtcb-1 enhanced α-syn-induced degeneration. Similar results were obtained when worms were exposed to the DA neurotoxin 6-hydroxydopamine. HSPC117 has been characterized recently as an essential subunit of the human tRNA splicing ligase complex. tRNA ligases have alternative functions in RNA repair and nonconventional mRNA splicing events. For example, in yeast, unconventional splicing of HAC1, a transcription factor that controls the unfolded protein response (UPR), is mediated by a tRNA ligase. In C. elegans, we demonstrate that RTCB-1 is necessary for xbp-1 (worm homolog of HAC1) mRNA splicing. Moreover, using a RNA ligase-dead mutant, we determine that the ligase activity of worm RTCB-1 is required for its neuroprotective role, which, in turn, is mediated through XBP-1 in the UPR pathway. Collectively, these studies highlight the mechanistic intersection of RNA processing and proteostasis in mediating neuroprotection.
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Dunys J, Duplan E, Checler F. The transcription factor X-box binding protein-1 in neurodegenerative diseases. Mol Neurodegener 2014; 9:35. [PMID: 25216759 PMCID: PMC4166022 DOI: 10.1186/1750-1326-9-35] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 08/14/2014] [Indexed: 12/12/2022] Open
Abstract
Endoplasmic reticulum (ER) is the cellular compartment where secreted and integral membrane proteins are folded and matured. The accumulation of unfolded or misfolded proteins triggers a stress that is physiologically controlled by an adaptative protective response called Unfolded Protein Response (UPR). UPR is primordial to induce a quality control response and to restore ER homeostasis. When this adaptative response is defective, protein aggregates overwhelm cells and affect, among other mechanisms, synaptic function, signaling transduction and cell survival. Such dysfunction likely contributes to several neurodegenerative diseases that are indeed characterized by exacerbated protein aggregation, protein folding impairment, increased ER stress and UPR activation. This review briefly documents various aspects of the biology of the transcription factor XBP-1 (X-box Binding Protein-1) and summarizes recent findings concerning its putative contribution to the altered UPR response observed in various neurodegenerative disorders including Parkinson’s and Alzheimer’s diseases.
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Affiliation(s)
| | | | - Frédéric Checler
- Institut de Pharmacologie Moléculaire et Cellulaire, UMR7275 CNRS-UNS, Sophia Antipolis, Nice, Valbonne F-06560, France.
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35
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Guerrero-Muñoz MJ, Castillo-Carranza DL, Kayed R. Therapeutic approaches against common structural features of toxic oligomers shared by multiple amyloidogenic proteins. Biochem Pharmacol 2014; 88:468-78. [PMID: 24406245 DOI: 10.1016/j.bcp.2013.12.023] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Revised: 12/18/2013] [Accepted: 12/19/2013] [Indexed: 02/03/2023]
Abstract
Impaired proteostasis is one of the main features of all amyloid diseases, which are associated with the formation of insoluble aggregates from amyloidogenic proteins. The aggregation process can be caused by overproduction or poor clearance of these proteins. However, numerous reports suggest that amyloid oligomers are the most toxic species, rather than insoluble fibrillar material, in Alzheimer's, Parkinson's, and Prion diseases, among others. Although the exact protein that aggregates varies between amyloid disorders, they all share common structural features that can be used as therapeutic targets. In this review, we focus on therapeutic approaches against shared features of toxic oligomeric structures and future directions.
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Affiliation(s)
- Marcos J Guerrero-Muñoz
- Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, TX, USA; Departments of Neurology, Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, TX, USA
| | - Diana L Castillo-Carranza
- Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, TX, USA; Departments of Neurology, Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, TX, USA
| | - Rakez Kayed
- Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, TX, USA; Departments of Neurology, Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, TX, USA.
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36
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Reinhardt S, Schuck F, Grösgen S, Riemenschneider M, Hartmann T, Postina R, Grimm M, Endres K. Unfolded protein response signaling by transcription factor XBP-1 regulates ADAM10 and is affected in Alzheimer's disease. FASEB J 2013; 28:978-97. [PMID: 24165480 DOI: 10.1096/fj.13-234864] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
In Alzheimer's disease (AD), disturbed homeostasis of the proteases competing for amyloid precursor protein processing has been reported: a disintegrin and metalloproteinase 10 (ADAM10), the physiological α-secretase, is decreased in favor of the amyloid-β-generating enzyme BACE-1. To identify transcription factors that modulate the expression of either protease, we performed a screening approach: 48 transcription factors significantly interfered with ADAM10/BACE-1-promoter activity. One selective inducer of ADAM10 gene expression is the X-box binding protein-1 (XBP-1). This protein regulates the unfolded protein-response pathway. We demonstrate that particularly the spliced XBP-1 variant dose dependently regulates ADAM10 expression, which can be synergistically enhanced by 100 nM insulin. Analysis of 2 different transgenic mouse models (APP/PS1 and 5xFAD) revealed that at early time points in pathology XBP-1 metabolism is induced. This is accompanied by a 2-fold augmented ADAM10 amount as compared with nontransgenic littermates (P=0.011). Along with aging of the mice, the system is counterregulated, and XBP-1 together with ADAM10 expression level decreased to ∼50% as compared with control animals. Analyses of expression levels in human AD brains showed that ADAM10 mRNA correlated with active XBP-1 (r=0.3120), but expression did not reach levels of healthy age-matched controls, suggesting deregulation of XBP-1 signaling. Our results demonstrate that XBP-1 is a driver of ADAM10 gene expression and that disturbance of this pathway might contribute to development or progression of AD.
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Affiliation(s)
- Sven Reinhardt
- 1Department of Psychiatry and Psychotherapy, University Medical Center of the Johannes Gutenberg University Mainz, Untere Zahlbacher Strasse 8, 55131 Mainz, Germany.
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Tau accumulation activates the unfolded protein response by impairing endoplasmic reticulum-associated degradation. J Neurosci 2013; 33:9498-507. [PMID: 23719816 DOI: 10.1523/jneurosci.5397-12.2013] [Citation(s) in RCA: 187] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
In Alzheimer's disease (AD), the mechanisms of neuronal loss remain largely unknown. Although tau pathology is closely correlated with neuronal loss, how its accumulation may lead to activation of neurotoxic pathways is unclear. Here we show that tau increased the levels of ubiquitinated proteins in the brain and triggered activation of the unfolded protein response (UPR). This suggested that tau interferes with protein quality control in the endoplasmic reticulum (ER). Consistent with this, ubiquitin was found to associate with the ER in human AD brains and tau transgenic (rTg4510) mouse brains, but this was not always colocalized with tau. The increased levels of ubiquitinated protein were accompanied by increased levels of phosphorylated protein kinase R-like ER kinase (pPERK), a marker that indicates UPR activation. Depleting soluble tau levels in cells and brain could reverse UPR activation. Tau accumulation facilitated its deleterious interaction with ER membrane and associated proteins that are essential for ER-associated degradation (ERAD), including valosin-containing protein (VCP) and Hrd1. Based on this, the effects of tau accumulation on ERAD efficiency were evaluated using the CD3δ reporter, an ERAD substrate. Indeed, CD3δ accumulated in both in vitro and in vivo models of tau overexpression and AD brains. These data suggest that soluble tau impairs ERAD and the result is activation of the UPR. The reversibility of this process, however, suggests that tau-based therapeutics could significantly delay this type of cell death and therefore disease progression.
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38
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Cornejo VH, Hetz C. The unfolded protein response in Alzheimer’s disease. Semin Immunopathol 2013; 35:277-92. [DOI: 10.1007/s00281-013-0373-9] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Accepted: 03/13/2013] [Indexed: 01/05/2023]
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39
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Mercado G, Valdés P, Hetz C. An ERcentric view of Parkinson's disease. Trends Mol Med 2013; 19:165-75. [DOI: 10.1016/j.molmed.2012.12.005] [Citation(s) in RCA: 148] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Revised: 12/18/2012] [Accepted: 12/27/2012] [Indexed: 01/28/2023]
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40
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Liu SY, Wang W, Cai ZY, Yao LF, Chen ZW, Wang CY, Zhao B, Li KS. Polymorphism -116C/G of human X-box-binding protein 1 promoter is associated with risk of Alzheimer's disease. CNS Neurosci Ther 2013; 19:229-34. [PMID: 23421912 DOI: 10.1111/cns.12064] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Revised: 01/08/2013] [Accepted: 01/10/2013] [Indexed: 01/14/2023] Open
Abstract
AIM Alzheimer's disease (AD) is a multifactor disease that has been reported to have a close association with endoplasmic reticulum (ER) stress response. In the response, the regulator factor human X-box-binding protein 1 (XBP1) has been shown to facilitate the refolding and degradation of misfolded proteins, prevent neurotoxicity of amyloid-beta (Aβ) and tau, and play an important role in the survival of neurons. The aim in the study was to analyze the potential association between the -116C/G polymorphism of XBP1 and the risk of AD. METHODS The association between -116C/G polymorphism of XBP1 promoter and possible risk of AD was assessed among 276 patients with AD and 254 matched healthy individuals in a case-control study. RESULTS Overall, there was a significantly statistical difference in genotype (P = 0.0354) and allele frequencies (P = 0.0150, OR = 1.3642, 95% CI = 1.0618-1.7528) between the AD subjects and control subjects, showing that the -116C/G polymorphism of XBP1 might lead to increased susceptibility for AD in a Chinese Han population. In addition, the -116CG and -116GG genotypes were significantly associated with increased AD risk in female (P = 0.0217) and in subjects with APOE є4 (-) (P = 0.0070) in stratified analyses, and the -116CC genotype was significantly associated with fast cognitive deterioration in the AD patients (P = 0.0270). CONCLUSION The study supports a role for the -116C/G polymorphism of XBP1 gene in the pathogenesis of AD, and further studies with a larger sample size and detailed data should be performed in other populations.
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Affiliation(s)
- Sheng-Yuan Liu
- Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases, Affiliated Hospital of Guangdong Medical College, Zhanjiang, China
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