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Saraiva MA. Temperature-Driven Stopped-Flow Experiments for Investigating the Initial Aggregation of the α-Synuclein Amyloid Protein, Focusing on Active and Inactive Phases. J Fluoresc 2024:10.1007/s10895-024-03971-8. [PMID: 39354189 DOI: 10.1007/s10895-024-03971-8] [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: 06/20/2024] [Accepted: 09/26/2024] [Indexed: 10/03/2024]
Abstract
The primary objective of this research is to further examine the events occurring during the active or burst phase by focusing on the aggregation of the Syn amyloid protein. Regarding this aspect, it was initially conducted rapid temperature variations using stopped-flow spectrometry and tyrosyl group fluorescence emission detection, within the initial 500 milliseconds in buffered Syn solutions at pH 7, exploring various temperature ranges to investigate protein aggregation. The results obtained were contrasted with results obtained for the Nα-acetyl-L-tyrosinamide (NAYA) parent compound in the same conditions. The utilization of the NAYA compound is suitable as it mimics the peptide bonds in proteins and contains a tyrosyl group resembling the four tyrosyl groups found in the Syn protein structure (the protein has no tryptophan residues). Furthermore, the NAYA compound adopts an intramolecularly hydrogen-bonded structure even in an aqueous solution, similar to the interactions seen in the hydrophilic face of β-sheets. Additionally, the Syn protein system can exhibit the presence of β-sheets as a result of the existence of very low abundant Syn amyloid precursor forms or nuclei during the initial stages of the protein aggregation. Thus, a relationship is present between the molecular processes in the NAYA and Syn protein systems, making the NAYA's application crucial in this research. Moreover, to aid in understanding the results, it was also compared the events during the quiescent or inactive phase (30-500 milliseconds) with those in the burst phase (up to 10 milliseconds) using stopped-flow spectrometry conditions. Steady-state measurements were beneficial in comprehending the occurrences in both the quiescent and burst phases examined. Although protein aggregation and disaggregation were observed during the quiescent phase, determining these processes in the burst phase was more challenging. In the latter case, the aggregation of the Syn protein is actually initiated by the interaction of the intrinsically disordered Syn monomers. In the quiescent phase, first-order rate constants were measured and analysis showed that Syn protein aggregation and disaggregation occur simultaneously. At lower temperatures, early protein disaggregation outweighs protein aggregation whereas at higher temperatures protein disaggregation and aggregation are rather similar. It is also need to highlight that the burst phase, while distinct from the quiescent phase, can be considered as a possible structural phase for obtaining details about the aggregation of this specific disordered protein in solution on a very short timescale.
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Affiliation(s)
- Marco A Saraiva
- Centro de Química Estrutural, Institute of Molecular Sciences, Instituto Superior Técnico, University of Lisbon, Campus Alameda, Av. Rovisco Pais, Lisbon, 1049-001, Portugal.
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, Oeiras, 2780-157, Portugal.
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Imaura R, Kawata Y, Matsuo K. Salt-Induced Hydrophobic C-Terminal Region of α-Synuclein Triggers Its Fibrillation under the Mimic Physiologic Condition. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:20537-20549. [PMID: 39285698 DOI: 10.1021/acs.langmuir.4c02178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/02/2024]
Abstract
α-Synuclein (αS) causes Parkinson's disease due to the structural alteration into amyloid fibrils that form after the interaction with synaptic membranes in neurons. To understand the alternation mechanism, the effect of salt (NaCl) on the interaction of αS with synaptic mimic membrane was characterized at the molecular level because salt triggered the amyloid fibril formation. The membrane-bound conformation (or the initial conformation before fibrillation) showed that NaCl decreased the number of helical structures and Tyr residues interacting with the membrane surface compared to when NaCl was absent, implying an increase in solvent-exposed regions. The N-terminal region of αS interacted with the membrane, forming the helical structures regardless of NaCl, while the C-terminal region formed a random structure with weak membrane interaction, but NaCl inhibited the interaction of its hydrophobic area, suggesting that salt promoted amyloid fibril formations by exposing the hydrophobic C-terminal region, which can intermolecularly interact with free αS.
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Affiliation(s)
- Ryota Imaura
- Graduate School of Advanced Science and Engineering, Hiroshima University, Hiroshima 739-8511, Japan
| | - Yasushi Kawata
- Graduate School of Engineering, Tottori University, Tottori 680-8552, Japan
| | - Koichi Matsuo
- Graduate School of Advanced Science and Engineering, Hiroshima University, Hiroshima 739-8511, Japan
- Research Institute for Synchrotron Radiation Science, Hiroshima University, Hiroshima 739-0046, Japan
- International Institute for Sustainability with Knotted Chiral Meta Matter (WPI-SKCM2), Hiroshima University, Hiroshima 739-0046, Japan
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Paulėkas E, Vanagas T, Lagunavičius S, Pajėdienė E, Petrikonis K, Rastenytė D. Navigating the Neurobiology of Parkinson's: The Impact and Potential of α-Synuclein. Biomedicines 2024; 12:2121. [PMID: 39335634 PMCID: PMC11429448 DOI: 10.3390/biomedicines12092121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2024] [Revised: 09/15/2024] [Accepted: 09/16/2024] [Indexed: 09/30/2024] Open
Abstract
Parkinson's disease (PD) is the second most prevalent neurodegenerative disease worldwide; therefore, since its initial description, significant progress has been made, yet a mystery remains regarding its pathogenesis and elusive root cause. The widespread distribution of pathological α-synuclein (αSyn) aggregates throughout the body raises inquiries regarding the etiology, which has prompted several hypotheses, with the most prominent one being αSyn-associated proteinopathy. The identification of αSyn protein within Lewy bodies, coupled with genetic evidence linking αSyn locus duplication, triplication, as well as point mutations to familial Parkinson's disease, has underscored the significance of αSyn in initiating and propagating Lewy body pathology throughout the brain. In monogenic and sporadic PD, the presence of early inflammation and synaptic dysfunction leads to αSyn aggregation and neuronal death through mitochondrial, lysosomal, and endosomal functional impairment. However, much remains to be understood about αSyn pathogenesis, which is heavily grounded in biomarkers and treatment strategies. In this review, we provide emerging new evidence on the current knowledge about αSyn's pathophysiological impact on PD, and its presumable role as a specific disease biomarker or main target of disease-modifying therapies, highlighting that this understanding today offers the best potential of disease-modifying therapy in the near future.
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Affiliation(s)
- Erlandas Paulėkas
- Department of Neurology, Lithuanian University of Health Sciences Kaunas Clinics, LT-50161 Kaunas, Lithuania; (T.V.); (S.L.); (E.P.); (K.P.); (D.R.)
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Zali A, Hajyani S, Salari M, Tajabadi-Ebrahimi M, Mortazavian AM, Pakpour B. Co-administration of probiotics and vitamin D reduced disease severity and complications in patients with Parkinson's disease: a randomized controlled clinical trial. Psychopharmacology (Berl) 2024; 241:1905-1914. [PMID: 38805039 DOI: 10.1007/s00213-024-06606-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Accepted: 05/02/2024] [Indexed: 05/29/2024]
Abstract
RATIONALE Probiotics have beneficial effects on the nervous system by modulating the gut-brain axis. Additionally, vitamin D supplementation presents a potential way for ameliorating neuropsychological disorders, particularly in regions with a high prevalence of vitamin D deficiency. OBJECTIVES The current clinical trial aimed to investigate the role of co-administered supplementation of probiotics and Vitamin D on the different inflammatory aspects of patients with Parkinson's disease. METHODS Forty-six patients with PD were recruited From the Functional Neurosurgery Research Center, Tehran, Iran. These patients were randomly allocated to one of the two treatment groups: Group A, who received probiotic/vitamin D supplements (n = 23), and Group B who received placebo capsules (n = 23) for 12 weeks. As primary outcomes, Interferon-Gamma (IFN-γ), interleukin 1 beta (IL-1β), IL-6, IL-10, Tumor Necrosis Factor-Alpha (TNF-α), total antioxidant capacity (TAC), and malondialdehyde (MDA) in serum were evaluated at the baseline and the end of the trial. Moreover, Additional questionnaire-based factors including gastrointestinal symptom rating scale (GSRS), Beck Anxiety Inventory (BAI), and Unified Parkinson's Disease Rating Scale (UPDRS) were evaluated. RESULTS Our findings demonstrated that the consumption of probiotic/vitamin D supplements leads to a significant decrease in IL-1β, INF-γ, IL-6, and MDA levels, while showing a significant increase in IL-10 and TAC levels compared to the placebo group (P < 0.05). Additionally, it leads to a significant decrease in the disease severity, anxiety, and gastrointestinal problems in PD patients in comparison to the placebo group (P < 0.05). CONCLUSIONS Given the acknowledged role of inflammation in the pathogenesis of Parkinson's disease on one hand, and the recognized anti-inflammatory and antioxidant effects associated with probiotics and vitamin D on the other hand, the concurrent administration of probiotics and vitamin D supplements emerges as a promising and potentially effective treatment option for individuals with PD.
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Affiliation(s)
- Alireza Zali
- Functional Neurosurgery Research Center, Shohada Tajrish Neurosurgical Center of Excellence, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Shirin Hajyani
- Department of Biology, Faculty of Sciences, Central Tehran Branch, Islamic Azad University, P O. Box: 14155-8189, Tehran, Iran
| | - Mehri Salari
- Functional Neurosurgery Research Center, Shohada Tajrish Neurosurgical Center of Excellence, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Maryam Tajabadi-Ebrahimi
- Department of Biology, Faculty of Sciences, Central Tehran Branch, Islamic Azad University, P O. Box: 14155-8189, Tehran, Iran.
| | - Amir M Mortazavian
- Food Safety Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Bahareh Pakpour
- Department of Biology, Faculty of Sciences, Central Tehran Branch, Islamic Azad University, P O. Box: 14155-8189, Tehran, Iran
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Baridjavadi Z, Mahmoudi M, Abdollahi N, Ebadpour N, Mollazadeh S, Haghmorad D, Esmaeili SA. The humoral immune landscape in Parkinson's disease: Unraveling antibody and B cell changes. Cell Biochem Funct 2024; 42:e4109. [PMID: 39189398 DOI: 10.1002/cbf.4109] [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: 05/15/2024] [Revised: 08/12/2024] [Accepted: 08/13/2024] [Indexed: 08/28/2024]
Abstract
Parkinson's disease (PD) is a complex neurodegenerative disorder characterized by the accumulation of α-synuclein (α-syn) in the brain and progressive loss of dopaminergic neurons in the substantia nigra (SN) region of the brain. Although the role of neuroinflammation and cellular immunity in PD has been extensively studied, the involvement of humoral immunity mediated by antibodies and B cells has received less attention. This article provides a comprehensive review of the current understanding of humoral immunity in PD. Here, we discuss alterations in B cells in PD, including changes in their number and phenotype. Evidence mostly indicates a decrease in the quantity of B cells in PD, accompanied by a shift in the population from naïve to memory cells. Furthermore, the existence of autoantibodies that target several antigens in PD has been investigated (i.e., anti-α-syn autoantibodies, anti-glial-derived antigen antibodies, anti-Tau antibodies, antineuromelanin antibodies, and antibodies against the renin-angiotensin system). Several autoantibodies are generated in PD, which may either provide protection or have harmful effects on disease progression. Furthermore, we have reviewed studies focusing on the utilization of antibodies as a potential treatment for PD, both in animal and clinical trials. This review sheds light on the intricate interplay between antibodies and the pathological processes in PD, including complement system activation.
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Affiliation(s)
- Zahra Baridjavadi
- Immunology Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
- Immunology Department, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
- Student Research Committee, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Mahmoud Mahmoudi
- Immunology Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
- Immunology Department, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Narges Abdollahi
- Immunology Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
- Immunology Department, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
- Student Research Committee, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Negar Ebadpour
- Immunology Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
- Immunology Department, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
- Student Research Committee, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Samaneh Mollazadeh
- Natural Products and Medicinal Plants Research Center, Khorasan University of Medical Sciences, Bojnurd, Iran
| | - Dariush Haghmorad
- Department of Immunology, Semnan University of Medical Sciences, Semnan, Iran
- Cancer Research Center, Semnan University of Medical Sciences, Semnan, Iran
| | - Seyed-Alireza Esmaeili
- Immunology Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
- Immunology Department, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
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Amaral L, Mendes F, Côrte-Real M, Rego A, Outeiro TF, Chaves SR. A versatile yeast model identifies the pesticides cymoxanil and metalaxyl as risk factors for synucleinopathies. CHEMOSPHERE 2024; 364:143039. [PMID: 39117080 DOI: 10.1016/j.chemosphere.2024.143039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 07/25/2024] [Accepted: 08/05/2024] [Indexed: 08/10/2024]
Abstract
Parkinson's disease (PD) is a neurodegenerative disorder characterized by the loss of dopaminergic neurons and the presence of Lewy bodies, which predominantly consist of aggregated forms of the protein alpha-synuclein (aSyn). While these aggregates are a pathological hallmark of PD, the etiology of most cases remains elusive. Although environmental risk factors have been identified, such as the pesticides dieldrin and MTPT, many others remain to be assessed and their molecular impacts are underexplored. This study aimed to identify pesticides that could enhance aSyn aggregation using a humanized yeast model expressing aSyn fused to GFP as a primary screening platform, which we validated using dieldrin. We found that the pesticides cymoxanil and metalaxyl induce aggregation of aSyn in yeast, which we confirmed also occurs in a model of aSyn inclusion formation using human H4 cells. In conclusion, our approach generated invaluable molecular data on the effect of pesticides, therefore providing insights into mechanisms associated with the onset and progression of PD and other synucleinopathies.
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Affiliation(s)
- Leslie Amaral
- CBMA - Centre of Molecular and Environmental Biology, ARNET - Aquatic Research Network, Department of Biology, School of Sciences, University of Minho, 4710-057, Braga, Portugal; University Medical Center Göttingen, Department of Experimental Neurodegeneration, Center for Biostructural Imaging of Neurodegeneration, Göttingen, Germany
| | - Filipa Mendes
- CBMA - Centre of Molecular and Environmental Biology, ARNET - Aquatic Research Network, Department of Biology, School of Sciences, University of Minho, 4710-057, Braga, Portugal
| | - Manuela Côrte-Real
- CBMA - Centre of Molecular and Environmental Biology, ARNET - Aquatic Research Network, Department of Biology, School of Sciences, University of Minho, 4710-057, Braga, Portugal
| | - António Rego
- Centre of Biological Engineering (CEB), Department of Biological Engineering, University of Minho, Braga, Portugal
| | - Tiago F Outeiro
- University Medical Center Göttingen, Department of Experimental Neurodegeneration, Center for Biostructural Imaging of Neurodegeneration, Göttingen, Germany; Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle Upon Tyne, NE2 4HH, UK; Max Planck Institute for Multidisciplinary Sciences, 37075, Göttingen, Germany; Scientific Employee With an Honorary Contract at Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE), Göttingen, Germany.
| | - Susana R Chaves
- CBMA - Centre of Molecular and Environmental Biology, ARNET - Aquatic Research Network, Department of Biology, School of Sciences, University of Minho, 4710-057, Braga, Portugal.
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7
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Tang Y, Zhang Y, Zhang D, Liu Y, Nussinov R, Zheng J. Exploring pathological link between antimicrobial and amyloid peptides. Chem Soc Rev 2024; 53:8713-8763. [PMID: 39041297 DOI: 10.1039/d3cs00878a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/24/2024]
Abstract
Amyloid peptides (AMYs) and antimicrobial peptides (AMPs) are considered as the two distinct families of peptides, characterized by their unique sequences, structures, biological functions, and specific pathological targets. However, accumulating evidence has revealed intriguing pathological connections between these peptide families in the context of microbial infection and neurodegenerative diseases. Some AMYs and AMPs share certain structural and functional characteristics, including the ability to self-assemble, the presence of β-sheet-rich structures, and membrane-disrupting mechanisms. These shared features enable AMYs to possess antimicrobial activity and AMPs to acquire amyloidogenic properties. Despite limited studies on AMYs-AMPs systems, the cross-seeding phenomenon between AMYs and AMPs has emerged as a crucial factor in the bidirectional communication between the pathogenesis of neurodegenerative diseases and host defense against microbial infections. In this review, we examine recent developments in the potential interplay between AMYs and AMPs, as well as their pathological implications for both infectious and neurodegenerative diseases. By discussing the current progress and challenges in this emerging field, this account aims to inspire further research and investments to enhance our understanding of the intricate molecular crosstalk between AMYs and AMPs. This knowledge holds great promise for the development of innovative therapies to combat both microbial infections and neurodegenerative disorders.
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Affiliation(s)
- Yijing Tang
- Department of Chemical, Biomolecular, and Corrosion Engineering, The University of Akron, Ohio 44325, USA.
| | - Yanxian Zhang
- Division of Endocrinology and Diabetes, Department of Pediatrics, School of Medicine, Stanford University, Palo Alto, CA 94304, USA
| | - Dong Zhang
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia 30332, USA
| | - Yonglan Liu
- Cancer Innovation Laboratory, National Cancer Institute, Frederick, MD 21702, USA
| | - Ruth Nussinov
- Computational Structural Biology Section, Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA.
- Department of Human Molecular Genetics and Biochemistry Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Jie Zheng
- Department of Chemical, Biomolecular, and Corrosion Engineering, The University of Akron, Ohio 44325, USA.
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Martins G, Galamba N. Wild-Type α-Synuclein Structure and Aggregation: A Comprehensive Coarse-Grained and All-Atom Molecular Dynamics Study. J Chem Inf Model 2024; 64:6115-6131. [PMID: 39046235 PMCID: PMC11323248 DOI: 10.1021/acs.jcim.4c00965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2024] [Revised: 07/14/2024] [Accepted: 07/18/2024] [Indexed: 07/25/2024]
Abstract
α-Synuclein (α-syn) is a 140 amino acid intrinsically disordered protein (IDP) and the primary component of cytotoxic oligomers implicated in the etiology of Parkinson's disease (PD). While IDPs lack a stable three-dimensional structure, they sample a heterogeneous ensemble of conformations that can, in principle, be assessed through molecular dynamics simulations. However, describing the structure and aggregation of large IDPs is challenging due to force field (FF) accuracy and sampling limitations. To cope with the latter, coarse-grained (CG) FFs emerge as a potential alternative at the expense of atomic detail loss. Whereas CG models can accurately describe the structure of the monomer, less is known about aggregation. The latter is key for assessing aggregation pathways and designing aggregation inhibitor drugs. Herein, we investigate the structure and dynamics of α-syn using different resolution CG (Martini3 and Sirah2) and all-atom (Amber99sb and Charmm36m) FFs to gain insight into the differences and resemblances between these models. The dependence of the magnitude of protein-water interactions and the putative need for enhanced sampling (replica exchange) methods in CG simulations are analyzed to distinguish between force field accuracy and sampling limitations. The stability of the CG models of an α-syn fibril was also investigated. Additionally, α-syn aggregation was studied through umbrella sampling for the CG models and CG/all-atom models for an 11-mer peptide (NACore) from an amyloidogenic domain of α-syn. Our results show that despite the α-syn structures of Martini3 and Sirah2 with enhanced protein-water interactions being similar, major differences exist concerning aggregation. The Martini3 fibril is not stable, and the binding free energy of α-syn and NACore is positive, opposite to Sirah2. Sirah2 peptides in a zwitterionic form, in turn, display termini interactions that are too strong, resulting in end-to-end orientation. Sirah2, with enhanced protein-water interactions and neutral termini, provides, however, a peptide aggregation free energy profile similar to that found with all-atom models. Overall, we find that Sirah2 with enhanced protein-water interactions is suitable for studying protein-protein and protein-drug aggregation.
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Affiliation(s)
- Gabriel
F. Martins
- BioISI—Biosystems
and Integrative Sciences Institute, Faculty
of Sciences of the University of Lisbon, C8, Campo Grande, 1749-016 Lisbon, Portugal
| | - Nuno Galamba
- BioISI—Biosystems
and Integrative Sciences Institute, Faculty
of Sciences of the University of Lisbon, C8, Campo Grande, 1749-016 Lisbon, Portugal
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Gatzemeier LM, Meyer F, Outeiro TF. Synthesis and Semi-Synthesis of Alpha-Synuclein: Insight into the Chemical Complexity of Synucleinopathies. Chembiochem 2024:e202400253. [PMID: 38965889 DOI: 10.1002/cbic.202400253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2024] [Revised: 07/04/2024] [Accepted: 07/04/2024] [Indexed: 07/06/2024]
Abstract
The chemical rules governing protein folding have intrigued generations of researchers for decades. With the advent of artificial intelligence (AI), prediction of protein structure has improved tremendously. However, there is still a level of analysis that is only possible through wet laboratory experiments, especially in respect to the investigation of the pathological effect of mutations and posttranslational modifications (PTMs) on proteins of interest. This requires the availability of pure peptides and proteins in sufficient quantities for biophysical, biochemical, and functional studies. In this context, chemical protein synthesis and semi-synthesis are powerful tools in protein research, which help to enlighten the role of protein modification in the physiology and pathology of proteins. A protein of high interest in the field of biomedicine is alpha-synuclein (aSyn), a protein deeply associated with several devastating neurodegenerative disorders such as Parkinson's disease (PD), dementia with Lewy bodies (DLB), or multiple systems atrophy (MSA). Here, we describe several methods and pathways to synthesize native or modified aSyn, and discuss how these approaches enable us to address pathological mechanisms that may open novel perspectives for therapeutic intervention.
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Affiliation(s)
- Luisa Maria Gatzemeier
- Institute of Organic and Biomolecular Chemistry, University of Göttingen, Tammannstraße 2, 37077, Göttingen, Germany
- Department of Experimental Neurodegeneration, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, Waldweg 33, 37073, Göttingen, Germany
| | - Franc Meyer
- Institute of Inorganic Chemistry, University of Göttingen, Tammannstraße 4, 37077, Göttingen, Germany
| | - Tiago Fleming Outeiro
- Department of Experimental Neurodegeneration, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, Waldweg 33, 37073, Göttingen, Germany
- Max Planck Institute for Multidisciplinary Sciences, Hermann-Rein-Straße 3, 37075, Göttingen, Germany
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle Upon Tyne, NE2 4HH, United Kingdom
- Scientific employee with an honorary contract at Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE), Von Siebold-Straße 3a, 37075, Göttingen, Germany
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Burré J, Edwards RH, Halliday G, Lang AE, Lashuel HA, Melki R, Murayama S, Outeiro TF, Papa SM, Stefanis L, Woerman AL, Surmeier DJ, Kalia LV, Takahashi R. Research Priorities on the Role of α-Synuclein in Parkinson's Disease Pathogenesis. Mov Disord 2024. [PMID: 38946200 DOI: 10.1002/mds.29897] [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: 01/05/2024] [Revised: 05/16/2024] [Accepted: 06/03/2024] [Indexed: 07/02/2024] Open
Abstract
Various forms of Parkinson's disease, including its common sporadic form, are characterized by prominent α-synuclein (αSyn) aggregation in affected brain regions. However, the role of αSyn in the pathogenesis and evolution of the disease remains unclear, despite vast research efforts of more than a quarter century. A better understanding of the role of αSyn, either primary or secondary, is critical for developing disease-modifying therapies. Previous attempts to hone this research have been challenged by experimental limitations, but recent technological advances may facilitate progress. The Scientific Issues Committee of the International Parkinson and Movement Disorder Society (MDS) charged a panel of experts in the field to discuss current scientific priorities and identify research strategies with potential for a breakthrough. © 2024 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Jacqueline Burré
- Appel Institute for Alzheimer's Disease Research and Brain and Mind Research Institute, Weill Cornell Medicine, New York, New York, USA
| | - Robert H Edwards
- Department of Physiology and Neurology, University of California, San Francisco School of Medicine, San Francisco, California, USA
| | - Glenda Halliday
- Brain and Mind Centre, School of Medical Sciences, The University of Sydney, Camperdown, New South Wales, Australia
| | - Anthony E Lang
- Edmond J. Safra Program in Parkinson's Disease, Krembil Research Institute, Toronto Western Hospital, University Health Network, Toronto, Ontario, Canada
- Division of Neurology, Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Hilal A Lashuel
- Laboratory of Chemical Biology of Neurodegeneration, Brain Mind Institute, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Ronald Melki
- Institut Francois Jacob (MIRCen), CEA and Laboratory of Neurodegenerative Diseases, CNRS, Fontenay-Aux-Roses, France
| | - Shigeo Murayama
- Department of Neuropathology, Tokyo Metropolitan Institute for Geriatrics and Gerontology, Tokyo, Japan
- The Brain Bank for Neurodevelopmental, Neurological and Psychiatric Disorders, United Graduate School of Child Development, Osaka University, Osaka, Japan
| | - Tiago F Outeiro
- Department of Experimental Neurodegeneration, University Medical Center, Göttingen, Germany
- Faculty of Medical Sciences, Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Stella M Papa
- Department of Neurology, School of Medicine, and Emory National Primate Research Center, Emory University, Atlanta, Georgia, USA
| | - Leonidas Stefanis
- First Department of Neurology, Eginitio Hospital, School of Medicine, National and Kapodistrian University of Athens, Athens, Greece
- Biomedical Research Foundation of the Academy of Athens, Athens, Greece
| | - Amanda L Woerman
- Department of Biology, Institute for Applied Life Sciences, University of Massachusetts Amherst, Amherst, Massachusetts, USA
- Department of Microbiology, Immunology, and Pathology, Prion Research Center, Colorado State University, Fort Collins, Colorado, USA
| | - Dalton James Surmeier
- Department of Neuroscience, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
- Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, Maryland, USA
| | - Lorraine V Kalia
- Edmond J. Safra Program in Parkinson's Disease, Krembil Research Institute, Toronto Western Hospital, University Health Network, Toronto, Ontario, Canada
- Division of Neurology, Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Ryosuke Takahashi
- Department of Neurology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
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Bordbar S, Alijanzadeh D, Samieefar N, Khazeei Tabari MA, Pourbakhtyaran E, Rezaei N. The Role of Alpha-Synuclein in Neurodevelopmental Diseases. Mol Neurobiol 2024:10.1007/s12035-024-04305-2. [PMID: 38949729 DOI: 10.1007/s12035-024-04305-2] [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: 07/13/2023] [Accepted: 06/11/2024] [Indexed: 07/02/2024]
Abstract
Neurodevelopmental disorders are a group of diseases with cognitive, motor, and emotional development deficits. Alpha-synuclein (α-syn) is a synaptic protein involved in transmission and neurodevelopment. This protein was previously shown to be associated with several disorders, including Parkinson's disease. Furthermore, a close link between neurodevelopmental disorders and Parkinson's has also been found. Changes in synaptic function have been noticed in neurodevelopmental disorders, including autism spectrum disorder. Impaired neurogenesis and related cognitive problems have been associated with altered expression of α-syn. Various studies reported α-syn in different body fluids and tissues such as blood and serum. Alpha-synuclein can help in better understanding the pathogenesis of neurodevelopmental diseases and facilitating their early diagnosis. This review aims to go over the recent advances in the role of α-syn in the pathophysiology of neurodevelopmental disorders, including autism spectrum disorder, attention deficit hyperactivity disorder, and motor and social impairment, and its value as a diagnostic biomarker.
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Affiliation(s)
- Sanaz Bordbar
- Students' Scientific Research Center, Tehran University of Medical Sciences, Tehran, 1417755331, Iran
- Network of Interdisciplinarity in Neonates and Infants (NINI), Universal Scientific Education and Research Network (USERN), Tehran, Iran
| | - Dorsa Alijanzadeh
- Network of Interdisciplinarity in Neonates and Infants (NINI), Universal Scientific Education and Research Network (USERN), Tehran, Iran
- School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- USERN Office, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Noosha Samieefar
- Network of Interdisciplinarity in Neonates and Infants (NINI), Universal Scientific Education and Research Network (USERN), Tehran, Iran
- School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- USERN Office, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Amin Khazeei Tabari
- Network of Interdisciplinarity in Neonates and Infants (NINI), Universal Scientific Education and Research Network (USERN), Tehran, Iran
- Student Research Committee, Mazandaran University of Medical Sciences, Sari, Iran
- USERN Office, Mazandaran University of Medical Sciences, Sari, Iran
| | - Elham Pourbakhtyaran
- Network of Interdisciplinarity in Neonates and Infants (NINI), Universal Scientific Education and Research Network (USERN), Tehran, Iran
- School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Department of Pediatric Neurology, Pediatrics Center of Excellence, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Nima Rezaei
- Network of Interdisciplinarity in Neonates and Infants (NINI), Universal Scientific Education and Research Network (USERN), Tehran, Iran.
- Research Center for Immunodeficiencies, Pediatrics Center of Excellence, Children's Medical Center Hospital, Tehran University of Medical Sciences, Dr. Qarib St., Keshavarz Blvd, Tehran, 14194, Iran.
- Department of Immunology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
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12
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Masato A, Bubacco L. The αSynuclein half-life conundrum. Neurobiol Dis 2024; 196:106524. [PMID: 38705490 DOI: 10.1016/j.nbd.2024.106524] [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: 03/04/2024] [Revised: 04/22/2024] [Accepted: 05/02/2024] [Indexed: 05/07/2024] Open
Abstract
αSynuclein (αSyn) misfolding and aggregation frequently precedes neuronal loss associated with Parkinson's Disease (PD) and other Synucleinopathies. The progressive buildup of pathological αSyn species results from alterations on αSyn gene and protein sequence, increased local concentrations, variations in αSyn interactome and protein network. Therefore, under physiological conditions, it is mandatory to regulate αSyn proteostasis as an equilibrium among synthesis, trafficking, degradation and extracellular release. In this frame, a crucial parameter is protein half-life. It provides indications of the turnover of a specific protein and depends on mRNA synthesis and translation regulation, subcellular localization, function and clearance by the designated degradative pathways. For αSyn, the molecular mechanisms regulating its proteostasis in neurons have been extensively investigated in various cellular models, either using biochemical or imaging approaches. Nevertheless, a converging estimate of αSyn half-life has not emerged yet. Here, we discuss the challenges in studying αSyn proteostasis under physiological and pathological conditions, the advantages and disadvantages of the experimental strategies proposed so far, and the relevance of determining αSyn half-life from a translational perspective.
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Affiliation(s)
- Anna Masato
- UK Dementia Research Institute at University College London, London, United Kingdom.
| | - Luigi Bubacco
- Department of Biology, University of Padova, Padova, Italy; Centro Studi per la Neurodegenerazione (CESNE), University of Padova, Padova, Italy.
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13
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Luong KD, Singh A. Application of Transformers in Cheminformatics. J Chem Inf Model 2024; 64:4392-4409. [PMID: 38815246 PMCID: PMC11167597 DOI: 10.1021/acs.jcim.3c02070] [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: 12/28/2023] [Revised: 04/05/2024] [Accepted: 05/06/2024] [Indexed: 06/01/2024]
Abstract
By accelerating time-consuming processes with high efficiency, computing has become an essential part of many modern chemical pipelines. Machine learning is a class of computing methods that can discover patterns within chemical data and utilize this knowledge for a wide variety of downstream tasks, such as property prediction or substance generation. The complex and diverse chemical space requires complex machine learning architectures with great learning power. Recently, learning models based on transformer architectures have revolutionized multiple domains of machine learning, including natural language processing and computer vision. Naturally, there have been ongoing endeavors in adopting these techniques to the chemical domain, resulting in a surge of publications within a short period. The diversity of chemical structures, use cases, and learning models necessitate a comprehensive summarization of existing works. In this paper, we review recent innovations in adapting transformers to solve learning problems in chemistry. Because chemical data is diverse and complex, we structure our discussion based on chemical representations. Specifically, we highlight the strengths and weaknesses of each representation, the current progress of adapting transformer architectures, and future directions.
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Affiliation(s)
- Kha-Dinh Luong
- Department of Computer Science, University of California Santa Barbara, Santa Barbara, CA 93106, United States
| | - Ambuj Singh
- Department of Computer Science, University of California Santa Barbara, Santa Barbara, CA 93106, United States
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14
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Bohid S, Ali LK, Romero-Leguizamón CR, Langkilde AE, Dos Santos AB, Kohlmeier KA. Sex-dependent effects of monomeric α-synuclein on calcium and cell death of lateral hypothalamic mouse neurons are altered by orexin. Mol Cell Neurosci 2024; 129:103934. [PMID: 38701995 DOI: 10.1016/j.mcn.2024.103934] [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: 09/19/2023] [Revised: 03/25/2024] [Accepted: 04/28/2024] [Indexed: 05/06/2024] Open
Abstract
Parkinson's Disease (PD) patients experience sleeping disorders in addition to the disease-defining symptomology of movement dysfunctions. The prevalence of PD is sex-based and presence of sleeping disorders in PD also shows sex bias with a stronger phenotype in males. In addition to loss of dopamine-containing neurons in the striatum, arousal-related, orexin-containing neurons in the lateral hypothalamus (LH) are lost in PD, which could contribute to state-related disorders. As orexin has been shown to be involved in sleeping disorders and to have neuroprotective effects, we asked whether orexin could protect sleep-related LH neurons from damage putatively from the protein α-synuclein (α-syn), which is found at high levels in the PD brain and that we have shown is associated with putatively excitotoxic rises in intracellular calcium in brainstem sleep-controlling nuclei, especially in males. Accordingly, we monitored intracellular calcium transients induced by α-syn and whether concurrent exposure to orexin affected those transients in LH cells of the mouse brain slice using calcium imaging. Further, we used an assay of cell death to determine whether LH cell viability was influenced when α-syn and orexin were co-applied when compared to exposure to α-syn alone. We found that excitatory calcium events induced by α-syn were reduced in amplitude and frequency when orexin was co-applied, and when data were evaluated by sex, this effect was found to be greater in females. In addition, α-syn exposure was associated with cell death that was higher in males, and interestingly, reduced cell death was noted when orexin was present, which did not show a sex bias. We interpret our findings to indicate that orexin is protective to α-syn-mediated damage to hypothalamic neurons, and the actions of orexin on α-syn-induced cellular effects differ between sexes, which could underlie sex-based differences in sleeping disorders in PD.
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Affiliation(s)
- Sara Bohid
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Lara Kamal Ali
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Cesar Ramon Romero-Leguizamón
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, 2100 Copenhagen, Denmark.
| | - Annette E Langkilde
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, 2100 Copenhagen, Denmark.
| | - Altair Brito Dos Santos
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Kristi A Kohlmeier
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, 2100 Copenhagen, Denmark.
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Ngwa HA, Bargues-Carot A, Jin H, Anantharam V, Kanthasamy A, Kanthasamy AG. Manganese and Vanadium Co-Exposure Induces Severe Neurotoxicity in the Olfactory System: Relevance to Metal-Induced Parkinsonism. Int J Mol Sci 2024; 25:5285. [PMID: 38791326 PMCID: PMC11121436 DOI: 10.3390/ijms25105285] [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: 03/28/2024] [Revised: 04/29/2024] [Accepted: 05/01/2024] [Indexed: 05/26/2024] Open
Abstract
Chronic environmental exposure to toxic heavy metals, which often occurs as a mixture through occupational and industrial sources, has been implicated in various neurological disorders, including Parkinsonism. Vanadium pentoxide (V2O5) typically presents along with manganese (Mn), especially in welding rods and high-capacity batteries, including electric vehicle batteries; however, the neurotoxic effects of vanadium (V) and Mn co-exposure are largely unknown. In this study, we investigated the neurotoxic impact of MnCl2, V2O5, and MnCl2-V2O5 co-exposure in an animal model. C57BL/6 mice were intranasally administered either de-ionized water (vehicle), MnCl2 (252 µg) alone, V2O5 (182 µg) alone, or a mixture of MnCl2 (252 µg) and V2O5 (182 µg) three times a week for up to one month. Following exposure, we performed behavioral, neurochemical, and histological studies. Our results revealed dramatic decreases in olfactory bulb (OB) weight and levels of tyrosine hydroxylase, dopamine, and 3,4-dihydroxyphenylacetic acid in the treatment groups compared to the control group, with the Mn/V co-treatment group producing the most significant changes. Interestingly, increased levels of α-synuclein expression were observed in the substantia nigra (SN) of treated animals. Additionally, treatment groups exhibited locomotor deficits and olfactory dysfunction, with the co-treatment group producing the most severe deficits. The treatment groups exhibited increased levels of the oxidative stress marker 4-hydroxynonenal in the striatum and SN, as well as the upregulation of the pro-apoptotic protein PKCδ and accumulation of glomerular astroglia in the OB. The co-exposure of animals to Mn/V resulted in higher levels of these metals compared to other treatment groups. Taken together, our results suggest that co-exposure to Mn/V can adversely affect the olfactory and nigral systems. These results highlight the possible role of environmental metal mixtures in the etiology of Parkinsonism.
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Affiliation(s)
- Hilary Afeseh Ngwa
- Iowa Center for Advanced Neurotoxicity, Department of Biomedical Sciences, Iowa State University, Ames, IA 50010, USA
| | - Alejandra Bargues-Carot
- Isakson Center for Neurological Disease Research, Department of Physiology and Pharmacology, University of Georgia, Athens, GA 30602, USA; (A.B.-C.); (H.J.); (V.A.)
| | - Huajun Jin
- Isakson Center for Neurological Disease Research, Department of Physiology and Pharmacology, University of Georgia, Athens, GA 30602, USA; (A.B.-C.); (H.J.); (V.A.)
| | - Vellareddy Anantharam
- Isakson Center for Neurological Disease Research, Department of Physiology and Pharmacology, University of Georgia, Athens, GA 30602, USA; (A.B.-C.); (H.J.); (V.A.)
| | - Arthi Kanthasamy
- Isakson Center for Neurological Disease Research, Department of Physiology and Pharmacology, University of Georgia, Athens, GA 30602, USA; (A.B.-C.); (H.J.); (V.A.)
| | - Anumantha G. Kanthasamy
- Iowa Center for Advanced Neurotoxicity, Department of Biomedical Sciences, Iowa State University, Ames, IA 50010, USA
- Isakson Center for Neurological Disease Research, Department of Physiology and Pharmacology, University of Georgia, Athens, GA 30602, USA; (A.B.-C.); (H.J.); (V.A.)
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16
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Lu X, Lu J, Li S, Feng S, Wang Y, Cui L. The Role of Liquid-Liquid Phase Separation in the Accumulation of Pathological Proteins: New Perspectives on the Mechanism of Neurodegenerative Diseases. Aging Dis 2024:AD.2024.0209. [PMID: 38739933 DOI: 10.14336/ad.2024.0209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Accepted: 04/20/2024] [Indexed: 05/16/2024] Open
Abstract
It is widely accepted that living organisms form highly dynamic membrane-less organelles (MLOS) with various functions through phase separation, and the indispensable role that phase separation plays in the mechanisms of normal physiological functions and pathogenesis is gradually becoming clearer. Pathological aggregates, regarded as hallmarks of neurodegenerative diseases, have been revealed to be closely related to aberrant phase separation. Specific proteins are assembled into condensates and transform into insoluble inclusions through aberrant phase separation, contributing to the development of diseases. In this review, we present an overview of the progress of phase separation research, involving its biological mechanisms and the status of research in neurodegenerative diseases, focusing on five main disease-specific proteins, tau, TDP-43, FUS, α-Syn and HTT, and how exactly these proteins reside within dynamic liquid-like compartments and thus turn into solid deposits. Further studies will yield new perspectives for understanding the aggregation mechanisms and potential therapeutic strategies, and future research directions are anticipated.
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Affiliation(s)
- Xingyu Lu
- Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Jiongtong Lu
- Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Shengnan Li
- Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Sifan Feng
- Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Yan Wang
- Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Lili Cui
- Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
- The Marine Biomedical Research Institute of Guangdong, School of Ocean and Tropical Medicine, Guangdong Medical University, Zhanjiang, Guangdong, China
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17
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Juković M, Ratkaj I, Kalafatovic D, Bradshaw NJ. Amyloids, amorphous aggregates and assemblies of peptides - Assessing aggregation. Biophys Chem 2024; 308:107202. [PMID: 38382283 DOI: 10.1016/j.bpc.2024.107202] [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: 11/29/2023] [Revised: 01/31/2024] [Accepted: 02/14/2024] [Indexed: 02/23/2024]
Abstract
Amyloid and amorphous aggregates represent the two major categories of aggregates associated with diseases, and although exhibiting distinct features, researchers often treat them as equivalent, which demonstrates the need for more thorough characterization. Here, we compare amyloid and amorphous aggregates based on their biochemical properties, kinetics, and morphological features. To further decipher this issue, we propose the use of peptide self-assemblies as minimalistic models for understanding the aggregation process. Peptide building blocks are significantly smaller than proteins that participate in aggregation, however, they make a plausible means to bridge the gap in discerning the aggregation process at the more complex, protein level. Additionally, we explore the potential use of peptide-inspired models to research the liquid-liquid phase separation as a feasible mechanism preceding amyloid formation. Connecting these concepts can help clarify our understanding of aggregation-related disorders and potentially provide novel drug targets to impede and reverse these serious illnesses.
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Affiliation(s)
- Maja Juković
- Faculty of Biotechnology and Drug Development, University of Rijeka, 51000 Rijeka, Croatia
| | - Ivana Ratkaj
- Faculty of Biotechnology and Drug Development, University of Rijeka, 51000 Rijeka, Croatia
| | - Daniela Kalafatovic
- Faculty of Biotechnology and Drug Development, University of Rijeka, 51000 Rijeka, Croatia.
| | - Nicholas J Bradshaw
- Faculty of Biotechnology and Drug Development, University of Rijeka, 51000 Rijeka, Croatia.
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18
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Sharma K, Chib S, Gupta A, Singh R, Chalotra R. Interplay between α-synuclein and parkin genes: Insights of Parkinson's disease. Mol Biol Rep 2024; 51:586. [PMID: 38683365 DOI: 10.1007/s11033-024-09520-7] [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: 01/25/2024] [Accepted: 04/03/2024] [Indexed: 05/01/2024]
Abstract
Parkinson's disease (PD) is a complex and debilitating neurodegenerative disorder characterized by the progressive loss of dopaminergic neurons in the substantia nigra. The pathogenesis of PD is intimately linked to the roles of two key molecular players, α-synuclein (α-syn) and Parkin. Understanding the intricate interplay between α-syn and Parkin is essential for unravelling the molecular underpinnings of PD. Their roles in synaptic function and protein quality control underscore their significance in neuronal health. Dysregulation of these processes, as seen in PD, highlights the potential for targeted therapeutic strategies aimed at restoring normal protein homeostasis and mitigating neurodegeneration. Investigating the connections between α-syn, Parkin, and various pathological mechanisms provides insights into the complex web of factors contributing to PD pathogenesis and offers hope for the development of more effective treatments for this devastating neurological disorder. The present compilation provides an overview of their structures, regional and cellular locations, associations, physiological functions, and pathological roles in the context of PD.
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Affiliation(s)
- Kajal Sharma
- Department of Pharmacology, Central University of Punjab, Bathinda, 151401, India
| | - Shivani Chib
- Department of Pharmacology, Central University of Punjab, Bathinda, 151401, India
| | - Aniket Gupta
- Department of Pharmacology, Central University of Punjab, Bathinda, 151401, India
| | - Randhir Singh
- Department of Pharmacology, Central University of Punjab, Bathinda, 151401, India.
| | - Rishabh Chalotra
- Department of Pharmacology, Central University of Punjab, Bathinda, 151401, India
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19
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Benson DR, Deng B, Kashipathy MM, Lovell S, Battaile KP, Cooper A, Gao P, Fenton AW, Zhu H. The N-terminal intrinsically disordered region of Ncb5or docks with the cytochrome b 5 core to form a helical motif that is of ancient origin. Proteins 2024; 92:554-566. [PMID: 38041394 PMCID: PMC10932899 DOI: 10.1002/prot.26647] [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: 07/21/2023] [Revised: 11/10/2023] [Accepted: 11/17/2023] [Indexed: 12/03/2023]
Abstract
NADH cytochrome b5 oxidoreductase (Ncb5or) is a cytosolic ferric reductase implicated in diabetes and neurological conditions. Ncb5or comprises cytochrome b5 (b5 ) and cytochrome b5 reductase (b5 R) domains separated by a CHORD-Sgt1 (CS) linker domain. Ncb5or redox activity depends on proper inter-domain interactions to mediate electron transfer from NADH or NADPH via FAD to heme. While full-length human Ncb5or has proven resistant to crystallization, we have succeeded in obtaining high-resolution atomic structures of the b5 domain and a construct containing the CS and b5 R domains (CS/b5 R). Ncb5or also contains an N-terminal intrinsically disordered region of 50 residues that has no homologs in other protein families in animals but features a distinctive, conserved L34 MDWIRL40 motif also present in reduced lateral root formation (RLF) protein in rice and increased recombination center 21 in baker's yeast, all attaching to a b5 domain. After unsuccessful attempts at crystallizing a human Ncb5or construct comprising the N-terminal region naturally fused to the b5 domain, we were able to obtain a high-resolution atomic structure of a recombinant rice RLF construct corresponding to residues 25-129 of human Ncb5or (52% sequence identity; 74% similarity). The structure reveals Trp120 (corresponding to invariant Trp37 in Ncb5or) to be part of an 11-residue α-helix (S116 QMDWLKLTRT126 ) packing against two of the four helices in the b5 domain that surround heme (α2 and α5). The Trp120 side chain forms a network of interactions with the side chains of four highly conserved residues corresponding to Tyr85 and Tyr88 (α2), Cys124 (α5), and Leu47 in Ncb5or. Circular dichroism measurements of human Ncb5or fragments further support a key role of Trp37 in nucleating the formation of the N-terminal helix, whose location in the N/b5 module suggests a role in regulating the function of this multi-domain redox enzyme. This study revealed for the first time an ancient origin of a helical motif in the N/b5 module as reflected by its existence in a class of cytochrome b5 proteins from three kingdoms among eukaryotes.
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Affiliation(s)
- David R. Benson
- Department of Chemistry, University of Kansas, Lawrence, KS 66045, U.S.A
| | - Bin Deng
- Department of Physical Therapy and Rehabilitation Science, University of Kansas Medical Center, Kansas City, KS 66160, U.S.A
| | - Maithri M. Kashipathy
- Department of Protein Structure and X-ray Crystallography Laboratory, The University of Kansas, 2034 Becker Drive, Lawrence, KS 66047, USA
| | - Scott Lovell
- Department of Protein Structure and X-ray Crystallography Laboratory, The University of Kansas, 2034 Becker Drive, Lawrence, KS 66047, USA
| | - Kevin P. Battaile
- Department of NYX, New York Structural Biology Center, Upton, NY, 11973, USA
| | - Anne Cooper
- Department of Protein Production Group, The University of Kansas, 2034 Becker Drive, Lawrence, KS 66047, USA
| | - Philip Gao
- Department of Protein Production Group, The University of Kansas, 2034 Becker Drive, Lawrence, KS 66047, USA
| | - Aron W. Fenton
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS 66160, U.S.A
| | - Hao Zhu
- Department of Clinical Laboratory Sciences, University of Kansas Medical Center, Kansas City, KS 66160, U.S.A
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS 66160, U.S.A
- Department of Physical Therapy and Rehabilitation Science, University of Kansas Medical Center, Kansas City, KS 66160, U.S.A
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20
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da Silva ANR, Pereira GRC, Bonet LFS, Outeiro TF, De Mesquita JF. In silico analysis of alpha-synuclein protein variants and posttranslational modifications related to Parkinson's disease. J Cell Biochem 2024; 125:e30523. [PMID: 38239037 DOI: 10.1002/jcb.30523] [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: 08/10/2023] [Revised: 12/11/2023] [Accepted: 12/29/2023] [Indexed: 03/12/2024]
Abstract
Parkinson's disease (PD) is among the most prevalent neurodegenerative disorders, affecting over 10 million people worldwide. The protein encoded by the SNCA gene, alpha-synuclein (ASYN), is the major component of Lewy body (LB) aggregates, a histopathological hallmark of PD. Mutations and posttranslational modifications (PTMs) in ASYN are known to influence protein aggregation and LB formation, possibly playing a crucial role in PD pathogenesis. In this work, we applied computational methods to characterize the effects of missense mutations and PTMs on the structure and function of ASYN. Missense mutations in ASYN were compiled from the literature/databases and underwent a comprehensive predictive analysis. Phosphorylation and SUMOylation sites of ASYN were retrieved from databases and predicted by algorithms. ConSurf was used to estimate the evolutionary conservation of ASYN amino acids. Molecular dynamics (MD) simulations of ASYN wild-type and variants A30G, A30P, A53T, and G51D were performed using the GROMACS package. Seventy-seven missense mutations in ASYN were compiled. Although most mutations were not predicted to affect ASYN stability, aggregation propensity, amyloid formation, and chaperone binding, the analyzed mutations received relatively high rates of deleterious predictions and predominantly occurred at evolutionarily conserved sites within the protein. Moreover, our predictive analyses suggested that the following mutations may be possibly harmful to ASYN and, consequently, potential targets for future investigation: K6N, T22I, K34E, G36R, G36S, V37F, L38P, G41D, and K102E. The MD analyses pointed to remarkable flexibility and essential dynamics alterations at nearly all domains of the studied variants, which could lead to impaired contact between NAC and the C-terminal domain triggering protein aggregation. These alterations may have functional implications for ASYN and provide important insight into the molecular mechanism of PD, supporting the design of future biomedical research and improvements in existing therapies for the disease.
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Affiliation(s)
- Aloma N R da Silva
- Bioinformatics and Computational Biology Laboratory, Department of Genetics and Molecular Biology, Federal University of the State of Rio de Janeiro (UNIRIO), Rio de Janeiro, Rio de Janeiro, Brazil
| | - Gabriel R C Pereira
- Bioinformatics and Computational Biology Laboratory, Department of Genetics and Molecular Biology, Federal University of the State of Rio de Janeiro (UNIRIO), Rio de Janeiro, Rio de Janeiro, Brazil
| | - Luiz Felippe Sarmento Bonet
- Bioinformatics and Computational Biology Laboratory, Department of Genetics and Molecular Biology, Federal University of the State of Rio de Janeiro (UNIRIO), Rio de Janeiro, Rio de Janeiro, Brazil
| | - Tiago Fleming Outeiro
- Department of Experimental Neurodegeneration, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, Göttingen, Germany
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
- Max Planck Institute for Experimental Medicine, Göttingen, Germany
| | - Joelma F De Mesquita
- Bioinformatics and Computational Biology Laboratory, Department of Genetics and Molecular Biology, Federal University of the State of Rio de Janeiro (UNIRIO), Rio de Janeiro, Rio de Janeiro, Brazil
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21
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Choi HI, Kim T, Kim JW, Lee GJ, Choi J, Chae YJ, Kim E, Koo TS. Rat Pharmacokinetics and In Vitro Metabolite Identification of KM-819, a Parkinson's Disease Candidate, Using LC-MS/MS and LC-HRMS. Molecules 2024; 29:1004. [PMID: 38474516 DOI: 10.3390/molecules29051004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Revised: 01/31/2024] [Accepted: 02/23/2024] [Indexed: 03/14/2024] Open
Abstract
FAF1 (FAS-associated factor 1) is involved in the activation of Fas cell surface death receptors and plays a role in apoptosis and necrosis. In patients with Parkinson's disease, FAF1 is overexpressed in dopaminergic neurons in the substantia nigra. KM-819, an FAF1 inhibitor, has shown potential for preventing dopaminergic neuronal cell death, promoting the degradation of α-synuclein and preventing its accumulation. This study aimed to develop and validate a quantitative analytical method for determining KM-819 levels in rat plasma using liquid chromatography-tandem mass spectrometry. This method was then applied to pharmacokinetic (PK) studies in rats. The metabolic stability of KM-819 was assessed in rat, dog, and human hepatocytes. In vitro metabolite identification and metabolic pathways were investigated in rat, dog, and human hepatocytes. The structural analog of KM-819, namely N-[1-(4-bromobenzyl)-3,5-dimethyl-1H-pyrazol-4-yl]-2-(phenylsulfanyl) acetamide, served as the internal standard (IS). Proteins were precipitated from plasma samples using acetonitrile. Analysis was carried out using a reverse-phase C18 column with a mobile phase consisting of 0.1% formic acid in distilled water and 0.1% formic acid in acetonitrile. The analytical method developed for KM-819 exhibited linearity within the concentration range of 0.002-10 μg/mL in rat plasma. The precision and accuracy of the intra- and inter-day measurements were <15% for the lower limit of quantification (LLOQ) and all quality control samples. KM-819 demonstrated stability under various sample storage conditions (6 h at room temperature (25 °C), four weeks at -20 °C, three freeze-thaw cycles, and pretreated samples in the autosampler). The matrix effect and dilution integrity met the criteria set by the Food and Drug Administration and the European Medicines Agency. This sensitive, rapid, and reliable analytical method was successfully applied in pharmacokinetic studies in rats. Pharmacokinetic analysis revealed the dose-independent kinetics of KM-819 at 0.5-5 mg/kg, with a moderate oral bioavailability of ~20% in rats. The metabolic stability of KM-819 was also found to be moderate in rat, dog, and human hepatocytes. Metabolite identification in rat, dog, and human hepatocytes resulted in the discovery of six, six, and eight metabolites, respectively. Glucuronidation and mono-oxidation have been proposed as the major metabolic pathways. Overall, these findings contribute to a better understanding of the pharmacokinetic characteristics of KM-819, thereby aiding future clinical studies.
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Affiliation(s)
- Hae-In Choi
- Graduate School of New Drug Discovery and Development, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Taeheon Kim
- Graduate School of New Drug Discovery and Development, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Jin Woo Kim
- Graduate School of New Drug Discovery and Development, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Gi Ju Lee
- Graduate School of New Drug Discovery and Development, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Jinyoung Choi
- Graduate School of New Drug Discovery and Development, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Yoon-Jee Chae
- College of Pharmacy, Woosuk University, Wanju 55338, Republic of Korea
| | - Eunhee Kim
- College of Biological Sciences and Biotechnology, Chungnam National University, Daejeon 34134, Republic of Korea
- Biopharmaceutical Division, Kainos Medicine Inc., Seongnam 13488, Republic of Korea
| | - Tae-Sung Koo
- Graduate School of New Drug Discovery and Development, Chungnam National University, Daejeon 34134, Republic of Korea
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22
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Mahbub NU, Islam MM, Hong ST, Chung HJ. Dysbiosis of the gut microbiota and its effect on α-synuclein and prion protein misfolding: consequences for neurodegeneration. Front Cell Infect Microbiol 2024; 14:1348279. [PMID: 38435303 PMCID: PMC10904658 DOI: 10.3389/fcimb.2024.1348279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2023] [Accepted: 01/24/2024] [Indexed: 03/05/2024] Open
Abstract
Abnormal behavior of α-synuclein and prion proteins is the hallmark of Parkinson's disease (PD) and prion illnesses, respectively, being complex neurological disorders. A primary cause of protein aggregation, brain injury, and cognitive loss in prion illnesses is the misfolding of normal cellular prion proteins (PrPC) into an infectious form (PrPSc). Aggregation of α-synuclein causes disruptions in cellular processes in Parkinson's disease (PD), leading to loss of dopamine-producing neurons and motor symptoms. Alteration in the composition or activity of gut microbes may weaken the intestinal barrier and make it possible for prions to go from the gut to the brain. The gut-brain axis is linked to neuroinflammation; the metabolites produced by the gut microbiota affect the aggregation of α-synuclein, regulate inflammation and immunological responses, and may influence the course of the disease and neurotoxicity of proteins, even if their primary targets are distinct proteins. This thorough analysis explores the complex interactions that exist between the gut microbiota and neurodegenerative illnesses, particularly Parkinson's disease (PD) and prion disorders. The involvement of the gut microbiota, a complex collection of bacteria, archaea, fungi, viruses etc., in various neurological illnesses is becoming increasingly recognized. The gut microbiome influences neuroinflammation, neurotransmitter synthesis, mitochondrial function, and intestinal barrier integrity through the gut-brain axis, which contributes to the development and progression of disease. The review delves into the molecular mechanisms that underlie these relationships, emphasizing the effects of microbial metabolites such as bacterial lipopolysaccharides (LPS), and short-chain fatty acids (SCFAs) in regulating brain functioning. Additionally, it looks at how environmental influences and dietary decisions affect the gut microbiome and whether they could be risk factors for neurodegenerative illnesses. This study concludes by highlighting the critical role that the gut microbiota plays in the development of Parkinson's disease (PD) and prion disease. It also provides a promising direction for future research and possible treatment approaches. People afflicted by these difficult ailments may find hope in new preventive and therapeutic approaches if the role of the gut microbiota in these diseases is better understood.
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Affiliation(s)
- Nasir Uddin Mahbub
- Department of Biomedical Sciences and Institute for Medical Science, Jeonbuk National University Medical School, Jeonju, Republic of Korea
| | - Md Minarul Islam
- Department of Biomedical Sciences and Institute for Medical Science, Jeonbuk National University Medical School, Jeonju, Republic of Korea
| | - Seong-Tshool Hong
- Department of Biomedical Sciences and Institute for Medical Science, Jeonbuk National University Medical School, Jeonju, Republic of Korea
| | - Hea-Jong Chung
- Gwangju Center, Korea Basic Science Institute, Gwangju, Republic of Korea
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23
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Elbatrawy AA, Ademoye TA, Alnakhala H, Tripathi A, Zami A, Ostafe R, Dettmer U, Fortin JS. Discovery of small molecule benzothiazole and indole derivatives tackling tau 2N4R and α-synuclein fibrils. Bioorg Med Chem 2024; 100:117613. [PMID: 38330847 PMCID: PMC10921547 DOI: 10.1016/j.bmc.2024.117613] [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: 12/02/2023] [Revised: 01/23/2024] [Accepted: 01/26/2024] [Indexed: 02/10/2024]
Abstract
Tau and α-synuclein aggregates are the main histopathological hallmarks present in Alzheimer's disease (AD), Parkinson's disease (PD), and other neurodegenerative disorders. Intraneuronal hyperphosphorylated tau accumulation is significantly connected to the degree of cognitive impairment in AD patients. In particular, the longest 2N4R tau isoform has a propensity to rapidly form oligomers and mature fibrils. On the other hand, misfolding of α-synuclein (α-syn) is the characteristic feature in PD and dementia with Lewy bodies (DLB). There is a strong crosstalk between the two prone-to-aggregation proteins as they coprecipitated in some brains of AD, PD, and DLB patients. Simultaneous targeting of both proteinaceous oligomers and aggregates is still challenging. Here, we rationally designed and synthesized benzothiazole- and indole-based compounds using the structural hybridization strategy between the benzothiazole N744 cyanine dye and the diphenyl pyrazole Anle138b that showed anti-aggregation activity towards 2N4R tau and α-syn, respectively. The anti-aggregation effect of the prepared compounds was monitored using the thioflavin-T (ThT) fluorescence assay, while transmission electron microscopy (TEM) was employed to detect fibrils upon the completion of a time-course study with the ThT assay. Moreover, the photo-induced crosslinking of unmodified protein (PICUP) assay was used to determine the formation of oligomers. Specifically, compounds 46 and 48 demonstrated the highest anti-aggregation activity by decreasing the ThT fluorescence to 4.0 and 14.8%, respectively, against α-syn. Although no noticeable effect on 2N4R tau oligomers, 46 showed promising anti-oligomer activity against α-syn. Both compounds induced a significantly high anti-aggregation effect against the two protein fibrils as visualized by TEM. Moreover, compound 48 remarkably inhibited α-syn inclusion and cell confluence using M17D cells. Collectively, compounds 46 and 48 could serve as a basic structure for further optimization to develop clinically active AD and PD disease-modifying agents.
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Affiliation(s)
- Ahmed A Elbatrawy
- Department of Basic Medical Sciences, College of Veterinary Medicine, Purdue University, West Lafayette, IN 47907, USA
| | - Taiwo A Ademoye
- Department of Basic Medical Sciences, College of Veterinary Medicine, Purdue University, West Lafayette, IN 47907, USA
| | - Heba Alnakhala
- Ann Romney Center for Neurologic Diseases, Department of Neurology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Arati Tripathi
- Ann Romney Center for Neurologic Diseases, Department of Neurology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Ashique Zami
- Molecular Evolution, Protein Engineering, and Production facility in Discovery Park, Purdue University, West Lafayette, IN 47907, USA
| | - Raluca Ostafe
- Molecular Evolution, Protein Engineering, and Production facility in Discovery Park, Purdue University, West Lafayette, IN 47907, USA
| | - Ulf Dettmer
- Ann Romney Center for Neurologic Diseases, Department of Neurology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Jessica S Fortin
- Department of Basic Medical Sciences, College of Veterinary Medicine, Purdue University, West Lafayette, IN 47907, USA.
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24
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Das D, Mattaparthi VSK. Computational investigation on the conformational dynamics of C-terminal truncated α-synuclein bound to membrane. J Biomol Struct Dyn 2024:1-13. [PMID: 38321955 DOI: 10.1080/07391102.2024.2310788] [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: 10/17/2023] [Accepted: 01/22/2024] [Indexed: 02/08/2024]
Abstract
Accelerated progression rates in Parkinson's disease (PD) have been linked to C-terminal domain (CTD) truncations of monomeric α-Synuclein (α-Syn), which have been suggested to increase amyloid aggregation in vivo and in vitro. In the brain of PD patients, CTD truncated α-Syn was found to have lower cell viability and tends to increase in the formation of fibrils. The CTD of α-Syn acts as a guard for regulating the normal functioning of α-Syn. The absence of the CTD may allow the N-terminal of α-Syn to interact with the membrane thereby affecting the normal functioning of α-Syn, and all of which will affect the etiology of PD. In this study, the conformational dynamics of CTD truncated α-Syn (1-99 and 1-108) monomers and their effect on the protein-membrane interactions were demonstrated using the all-atom molecular dynamics (MD) simulation method. From the MD analyses, it was noticed that among the two truncated monomers, α-Syn (1-108) was found to be more stable, shows rigidness at the N-terminal region and contains a significant number of intermolecular hydrogen bonds between the non-amyloid β-component (NAC) region and membrane, and lesser number of extended strands. Further, the bending angle in the N-terminal domain was found to be lesser in the α-Syn (1-108) in comparison with the α-Syn (1-99). Our findings suggest that the truncation on the CTD of α-Syn affects its interaction with the membrane and subsequently has an impact on the aggregation.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Dorothy Das
- Molecular Modelling and Simulation Laboratory, Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur, Assam, India
| | - Venkata Satish Kumar Mattaparthi
- Molecular Modelling and Simulation Laboratory, Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur, Assam, India
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25
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Illes-Toth E, Rempel DL, Gross ML. Exploration of Resveratrol as a Potent Modulator of α-Synuclein Fibril Formation. ACS Chem Neurosci 2024; 15:503-516. [PMID: 38194353 PMCID: PMC10922803 DOI: 10.1021/acschemneuro.3c00571] [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] [Indexed: 01/10/2024] Open
Abstract
The molecular determinants of amyloid protein misfolding and aggregation are key for the development of therapeutic interventions in neurodegenerative disease. Although small synthetic molecules, bifunctional molecules, and natural products offer a potentially advantageous approach to therapeutics to remodel aggregation, their evaluation requires new platforms that are informed at the molecular level. To that end, we chose pulsed hydrogen/deuterium exchange mass spectrometry (HDX-MS) to discern the phenomena of aggregation modulation for a model system of alpha synuclein (αS) and resveratrol, an antiamyloid compound. We invoked, as a complement to HDX, advanced kinetic modeling described here to illuminate the details of aggregation and to determine the number of oligomeric populations by kinetically fitting the experimental data under conditions of limited proteolysis. The misfolding of αS is most evident within and nearby the nonamyloid-β component region, and resveratrol significantly remodels that aggregation. HDX distinguishes readily a less solvent-accessible, more structured oligomer that coexists with a solvent-accessible, more disordered oligomer during aggregation. A view of the misfolding emerges from time-dependent changes in the fractional species across the protein with or without resveratrol, while details were determined through kinetic modeling of the protected species. A detailed picture of the inhibitory action of resveratrol with time and regional specificity emerges, a picture that can be obtained for other inhibitors and amyloid proteins. Moreover, the model reveals that new states of aggregation are sampled, providing new insights on amyloid formation. The findings were corroborated by circular dichroism and transmission electron microscopy.
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Affiliation(s)
- Eva Illes-Toth
- Department of Chemistry, Washington University in St Louis, St Louis, Missouri 63130, United States
| | - Don L Rempel
- Department of Chemistry, Washington University in St Louis, St Louis, Missouri 63130, United States
| | - Michael L Gross
- Department of Chemistry, Washington University in St Louis, St Louis, Missouri 63130, United States
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26
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Savva L, Platts JA. Computational investigation of copper-mediated conformational changes in α-synuclein dimer. Phys Chem Chem Phys 2024; 26:2926-2935. [PMID: 38193190 DOI: 10.1039/d3cp04697d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2024]
Abstract
We report molecular dynamics simulation of dimers of α-synuclein, the peptide closely associated with onset of Parkinson's disease, both as metal-free dimer and with inter-chain bridging provided by Cu(II) ions. Our investigation reveals that the presence of copper-induced inter-chain bridging not only stabilizes α-synuclein dimers, but also leads to enhanced β-sheet formation at critical regions within the N-terminal and NAC regions of the protein. These contacts are larger and longer-lived in the presence of copper, and as a result each peptide chain is more extended and less flexible than in the metal-free dimer. The persistence of these inter-peptide contacts underscores their significance in stabilising the dimers, potentially influencing the aggregation pathway. Moreover, the increased flexibility in the two termini, as well as the absence of persistent contacts in the metal-free dimer, correlates with the presence of amorphous aggregates. This phenomenon is known to mitigate fibrillation, while their absence in the metal-bound dimer suggests an increased propensity to form fibrils in the presence of copper ions.
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Affiliation(s)
- Loizos Savva
- School of Chemistry, Cardiff University, Park Place, Cardiff CF10 3AT, UK.
| | - James A Platts
- School of Chemistry, Cardiff University, Park Place, Cardiff CF10 3AT, UK.
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27
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Gunasinghe KJ, Rahman T, Chee Wezen X. Unraveling the Behavior of Intrinsically Disordered Protein c-Myc: A Study Utilizing Gaussian-Accelerated Molecular Dynamics. ACS OMEGA 2024; 9:2250-2262. [PMID: 38250404 PMCID: PMC10795134 DOI: 10.1021/acsomega.3c05822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 11/02/2023] [Accepted: 11/21/2023] [Indexed: 01/23/2024]
Abstract
The protein c-Myc is a transcription factor that remains largely intrinsically disordered and is known to be involved in various biological processes and is overexpressed in various cancers, making it an attractive drug target. However, intrinsically disordered proteins such as c-Myc do not show funnel-like basins in their free-energy landscapes; this makes their druggability a challenge. For the first time, we propose a heterodimer model of c-Myc/Max in full length in this work. We used Gaussian-accelerated molecular dynamics (GaMD) simulations to explore the behavior of c-Myc and its various regions, including the transactivation domain (TAD) and the basic helix-loop-helix-leucine-zipper (bHLH-Zipper) motif in three different conformational states: (a) monomeric c-Myc, (b) c-Myc when bound to its partner protein, Max, and (c) when Max was removed after binding. We analyzed the GaMD trajectories using root-mean-square deviation (RMSD), radius of gyration, root-mean-square fluctuation, and free-energy landscape (FEL) calculations to elaborate the behaviors of these regions. The results showed that the monomeric c-Myc structure showed a higher RMSD fluctuation as compared with the c-Myc/Max heterodimer in the bHLH-Zipper motif. This indicated that the bHLH-Zipper motif of c-Myc is more stable when it is bound to Max. The TAD region in both monomeric and Max-bound states showed similar plasticity in terms of RMSD. We also conducted residue decomposition calculations and showed that the c-Myc and Max interaction could be driven mainly by electrostatic interactions and the residues Arg299, Ile403, and Leu420 seemed to play important roles in the interaction. Our work provides insights into the behavior of c-Myc and its regions that could support the development of drugs that target c-Myc and other intrinsically disordered proteins.
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Affiliation(s)
| | - Taufiq Rahman
- Department
of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, United Kingdom
| | - Xavier Chee Wezen
- Faculty
of Engineering, Computing and Science, Swinburne
University of Technology Sarawak, Kuching 93350, Malaysia
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28
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So YJ, Lee JU, Yang GS, Yang G, Kim SW, Lee JH, Kim JU. The Potentiality of Natural Products and Herbal Medicine as Novel Medications for Parkinson's Disease: A Promising Therapeutic Approach. Int J Mol Sci 2024; 25:1071. [PMID: 38256144 PMCID: PMC10816678 DOI: 10.3390/ijms25021071] [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: 01/09/2024] [Accepted: 01/12/2024] [Indexed: 01/24/2024] Open
Abstract
As the global population ages, the prevalence of Parkinson's disease (PD) is steadily on the rise. PD demonstrates chronic and progressive characteristics, and many cases can transition into dementia. This increases societal and economic burdens, emphasizing the need to find effective treatments. Among the widely recognized causes of PD is the abnormal accumulation of proteins, and autophagy dysfunction accelerates this accumulation. The resultant Lewy bodies are also commonly found in Alzheimer's disease patients, suggesting an increased potential for the onset of dementia. Additionally, the production of free radicals due to mitochondrial dysfunction contributes to neuronal damage and degeneration. The activation of astrocytes and the M1 phenotype of microglia promote damage to dopamine neurons. The drugs currently used for PD only delay the clinical progression and exacerbation of the disease without targeting its root cause, and come with various side effects. Thus, there is a demand for treatments with fewer side effects, with much potential offered by natural products. In this study, we reviewed a total of 14 articles related to herbal medicines and natural products and investigated their relevance to possible PD treatment. The results showed that the reviewed herbal medicines and natural products are effective against lysosomal disorder, mitochondrial dysfunction, and inflammation, key mechanisms underlying PD. Therefore, natural products and herbal medicines can reduce neurotoxicity and might improve both motor and non-motor symptoms associated with PD. Furthermore, these products, with their multi-target effects, enhance bioavailability, inhibit antibiotic resistance, and might additionally eliminate side effects, making them good alternative therapies for PD treatment.
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Affiliation(s)
- Yu-Jin So
- College of Korean Medicine, Woosuk University, Jeonju-si 54986, Jeollabuk-do, Republic of Korea; (Y.-J.S.); (J.-U.L.); (G.-S.Y.); (G.Y.); (S.-W.K.)
| | - Jae-Ung Lee
- College of Korean Medicine, Woosuk University, Jeonju-si 54986, Jeollabuk-do, Republic of Korea; (Y.-J.S.); (J.-U.L.); (G.-S.Y.); (G.Y.); (S.-W.K.)
| | - Ga-Seung Yang
- College of Korean Medicine, Woosuk University, Jeonju-si 54986, Jeollabuk-do, Republic of Korea; (Y.-J.S.); (J.-U.L.); (G.-S.Y.); (G.Y.); (S.-W.K.)
| | - Gabsik Yang
- College of Korean Medicine, Woosuk University, Jeonju-si 54986, Jeollabuk-do, Republic of Korea; (Y.-J.S.); (J.-U.L.); (G.-S.Y.); (G.Y.); (S.-W.K.)
| | - Sung-Wook Kim
- College of Korean Medicine, Woosuk University, Jeonju-si 54986, Jeollabuk-do, Republic of Korea; (Y.-J.S.); (J.-U.L.); (G.-S.Y.); (G.Y.); (S.-W.K.)
| | - Jun-Ho Lee
- College of Korean Medicine, Woosuk University, Jeonju-si 54986, Jeollabuk-do, Republic of Korea; (Y.-J.S.); (J.-U.L.); (G.-S.Y.); (G.Y.); (S.-W.K.)
- Da CaPo Co., Ltd., 303 Cheonjam-ro, Wansan-gu, Jeonju-si 55069, Jeollabuk-do, Republic of Korea
| | - Jong-Uk Kim
- College of Korean Medicine, Woosuk University, Jeonju-si 54986, Jeollabuk-do, Republic of Korea; (Y.-J.S.); (J.-U.L.); (G.-S.Y.); (G.Y.); (S.-W.K.)
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29
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Sanyal A, Scanavachi G, Somerville E, Saminathan A, Nair A, Oikonomou A, Hatzakis NS, Kirchhausen T. Constitutive Endolysosomal Perforation in Neurons allows Induction of α-Synuclein Aggregation by Internalized Pre-Formed Fibrils. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.12.30.573738. [PMID: 38260258 PMCID: PMC10802249 DOI: 10.1101/2023.12.30.573738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
The endocytic pathway is both an essential route of molecular uptake in cells and a potential entry point for pathology-inducing cargo. The cell-to-cell spread of cytotoxic aggregates, such as those of α-synuclein (α-syn) in Parkinson's Disease (PD), exemplifies this duality. Here we used a human iPSC-derived induced neuronal model (iNs) prone to death mediated by aggregation in late endosomes and lysosomes of endogenous α-syn, seeded by internalized pre-formed fibrils of α-syn (PFFs). This PFF-mediated death was not observed with parental iPSCs or other non-neuronal cells. Using live-cell optical microscopy to visualize the read out of biosensors reporting endo-lysosome wounding, we discovered that up to about 10% of late endosomes and lysosomes in iNs exhibited spontaneous constitutive perforations, regardless of the presence of internalized PFFs. This wounding, absent in parental iPSCs and non-neuronal cells, corresponded to partial damage by nanopores in the limiting membranes of a subset of endolysosomes directly observed by volumetric focused ion beam scanning electron microscopy (FIB-SEM) in iNs and in CA1 pyramidal neurons from mouse brain, and not found in iPSCs or in other non-neuronal cells in culture or in mouse liver and skin. We suggest that the compromised limiting membranes in iNs and neurons in general are the primary conduit for cytosolic α-syn to access PFFs entrapped within endo-lysosomal lumens, initiating PFF-mediated α-syn aggregation. Significantly, eradicating the intrinsic endolysosomal perforations in iNs by inhibiting the endosomal Phosphatidylinositol-3-Phosphate/Phosphatidylinositol 5-Kinase (PIKfyve kinase) using Apilimod or Vacuolin-1 markedly reduced PFF-induced α-syn aggregation, despite PFFs continuing to enter the endolysosomal compartment. Crucially, this intervention also diminished iN death associated with PFF incubation. Our results reveal the surprising presence of intrinsically perforated endo-lysosomes in neurons, underscoring their crucial early involvement in the genesis of toxic α-syn aggregates induced by internalized PFFs. This discovery offers a basis for employing PIKfyve kinase inhibition as a potential therapeutic strategy to counteract synucleinopathies.
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Affiliation(s)
- Anwesha Sanyal
- Department of Cell Biology, Harvard Medical School, 200 Longwood Ave, Boston, MA 02115, USA
- Program in Cellular and Molecular Medicine, Boston Children’s Hospital, 200 Longwood Ave, Boston, MA 02115, USA
| | - Gustavo Scanavachi
- Department of Cell Biology, Harvard Medical School, 200 Longwood Ave, Boston, MA 02115, USA
- Program in Cellular and Molecular Medicine, Boston Children’s Hospital, 200 Longwood Ave, Boston, MA 02115, USA
| | - Elliott Somerville
- Program in Cellular and Molecular Medicine, Boston Children’s Hospital, 200 Longwood Ave, Boston, MA 02115, USA
| | - Anand Saminathan
- Department of Cell Biology, Harvard Medical School, 200 Longwood Ave, Boston, MA 02115, USA
- Program in Cellular and Molecular Medicine, Boston Children’s Hospital, 200 Longwood Ave, Boston, MA 02115, USA
| | - Athul Nair
- Program in Cellular and Molecular Medicine, Boston Children’s Hospital, 200 Longwood Ave, Boston, MA 02115, USA
| | | | - Nikos S. Hatzakis
- Department of Chemistry University of Copenhagen, 2100 Copenhagen, Denmark
| | - Tom Kirchhausen
- Department of Cell Biology, Harvard Medical School, 200 Longwood Ave, Boston, MA 02115, USA
- Program in Cellular and Molecular Medicine, Boston Children’s Hospital, 200 Longwood Ave, Boston, MA 02115, USA
- Department of Pediatrics, Harvard Medical School, 200 Longwood Ave, Boston, MA 02115, USA
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30
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Jastrzębski MK, Wójcik P, Stępnicki P, Kaczor AA. Effects of small molecules on neurogenesis: Neuronal proliferation and differentiation. Acta Pharm Sin B 2024; 14:20-37. [PMID: 38239239 PMCID: PMC10793103 DOI: 10.1016/j.apsb.2023.10.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Revised: 09/06/2023] [Accepted: 09/13/2023] [Indexed: 01/22/2024] Open
Abstract
Neurons are believed to be non-proliferating cells. However, neuronal stem cells are still present in certain areas of the adult brain, although their proliferation diminishes with age. Just as with other cells, their proliferation and differentiation are modulated by various mechanisms. These mechanisms are foundational to the strategies developed to induce neuronal proliferation and differentiation, with potential therapeutic applications for neurodegenerative diseases. The most common among these diseases are Parkinson's disease and Alzheimer's disease, associated with the formation of β -amyloid (Aβ ) aggregates which cause a reduction in the number of neurons. Compounds such as LiCl, 4-aminothiazoles, Pregnenolone, ACEA, harmine, D2AAK1, methyl 3,4-dihydroxybenzoate, and shikonin may induce neuronal proliferation/differentiation through the activation of pathways: MAPK ERK, PI3K/AKT, NFκ B, Wnt, BDNF, and NPAS3. Moreover, combinations of these compounds can potentially transform somatic cells into neurons. This transformation process involves the activation of neuron-specific transcription factors such as NEUROD1, NGN2, ASCL1, and SOX2, which subsequently leads to the transcription of downstream genes, culminating in the transformation of somatic cells into neurons. Neurodegenerative diseases are not the only conditions where inducing neuronal proliferation could be beneficial. Consequently, the impact of pro-proliferative compounds on neurons has also been researched in mouse models of Alzheimer's disease.
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Affiliation(s)
- Michał K. Jastrzębski
- Department of Synthesis and Chemical Technology of Pharmaceutical Substances with Computer Modeling Laboratory, Medical University of Lublin, Faculty of Pharmacy, Lublin PL-20093, Poland
| | - Piotr Wójcik
- Department of Synthesis and Chemical Technology of Pharmaceutical Substances with Computer Modeling Laboratory, Medical University of Lublin, Faculty of Pharmacy, Lublin PL-20093, Poland
| | - Piotr Stępnicki
- Department of Synthesis and Chemical Technology of Pharmaceutical Substances with Computer Modeling Laboratory, Medical University of Lublin, Faculty of Pharmacy, Lublin PL-20093, Poland
| | - Agnieszka A. Kaczor
- Department of Synthesis and Chemical Technology of Pharmaceutical Substances with Computer Modeling Laboratory, Medical University of Lublin, Faculty of Pharmacy, Lublin PL-20093, Poland
- School of Pharmacy, University of Eastern Finland, Kuopio FI-70211, Finland
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31
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Strunge K, Burgin T, Golbek TW, Roeters SJ, Pfaendtner J, Weidner T. Umbrella-like Helical Structure of α-Synuclein at the Air-Water Interface Observed with Experimental and Theoretical Sum Frequency Generation Spectroscopy. J Phys Chem Lett 2023; 14:11030-11035. [PMID: 38047768 DOI: 10.1021/acs.jpclett.3c02543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
The misfolding of α-synuclein (αS) into amyloid aggregates is catalyzed by hydrophobic surfaces and associated with severe brain disorders, such as Parkinson's disease. Despite the important role of interfaces, the three-dimensional structure of αS at the interfaces is still not clear. We report interface-specific sum frequency generation (SFG) experiments of monomeric αS binding to the air-water interface, a model system for the important hydrophobic surfaces. We combine the SFG spectra with calculations of theoretical spectra based on molecular dynamics simulations to show that αS, which is an intrinsically disordered protein in solution, folds into a defined, mostly helical secondary structure at the air-water interface. The binding pose resembles an umbrella shape, where the C-terminus protrudes into the water phase, while the N-terminus and the NAC region span the canopy at the interface. In this binding pose, αS is prone to aggregate, which could explain the catalytic effect of hydrophobic interfaces and air bubbles on αS fibrillation.
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Affiliation(s)
- Kris Strunge
- Department of Chemistry, Aarhus University, Langelandsgade 140, 8000 Aarhus C, Denmark
| | - Tucker Burgin
- Department of Chemical Engineering, University of Washington, Benson Hall 1750, Seattle, Washington 98195-1750, United States
| | - Thaddeus W Golbek
- Department of Chemistry, Aarhus University, Langelandsgade 140, 8000 Aarhus C, Denmark
| | - Steven J Roeters
- Department of Anatomy and Neurosciences, Vrije University, Boelelaan 1108, 1081 HZ Amsterdam, The Netherlands
| | - Jim Pfaendtner
- Department of Chemical Engineering, University of Washington, Benson Hall 1750, Seattle, Washington 98195-1750, United States
| | - Tobias Weidner
- Department of Chemistry, Aarhus University, Langelandsgade 140, 8000 Aarhus C, Denmark
- Department of Chemical Engineering, University of Washington, Benson Hall 1750, Seattle, Washington 98195-1750, United States
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32
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Liu Y, Wang X, Campolo G, Teng X, Ying L, Edel JB, Ivanov AP. Single-Molecule Detection of α-Synuclein Oligomers in Parkinson's Disease Patients Using Nanopores. ACS NANO 2023; 17:22999-23009. [PMID: 37947369 PMCID: PMC10690843 DOI: 10.1021/acsnano.3c08456] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 10/22/2023] [Accepted: 10/26/2023] [Indexed: 11/12/2023]
Abstract
α-Synuclein (α-Syn) is an intrinsically disordered protein whose aggregation in the brain has been significantly implicated in Parkinson's disease (PD). Beyond the brain, oligomers of α-Synuclein are also found in cerebrospinal fluid (CSF) and blood, where the analysis of these aggregates may provide diagnostic routes and enable a better understanding of disease mechanisms. However, detecting α-Syn in CSF and blood is challenging due to its heterogeneous protein size and shape, and low abundance in clinical samples. Nanopore technology offers a promising route for the detection of single proteins in solution; however, the method often lacks the necessary selectivity in complex biofluids, where multiple background biomolecules are present. We address these limitations by developing a strategy that combines nanopore-based sensing with molecular carriers that can specifically capture α-Syn oligomers with sizes of less than 20 nm. We demonstrate that α-Synuclein oligomers can be detected directly in clinical samples, with minimal sample processing, by their ion current characteristics and successfully utilize this technology to differentiate cohorts of PD patients from healthy controls. The measurements indicate that detecting α-Syn oligomers present in CSF may potentially provide valuable insights into the progression and monitoring of Parkinson's disease.
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Affiliation(s)
- Yaxian Liu
- Department
of Chemistry, Imperial College London, Molecular
Sciences Research Hub, London W12 0BZ, United
Kingdom
| | - Xiaoyi Wang
- Department
of Chemistry, Imperial College London, Molecular
Sciences Research Hub, London W12 0BZ, United
Kingdom
| | - Giulia Campolo
- Department
of Chemistry, Imperial College London, Molecular
Sciences Research Hub, London W12 0BZ, United
Kingdom
| | - Xiangyu Teng
- Department
of Chemistry, Imperial College London, Molecular
Sciences Research Hub, London W12 0BZ, United
Kingdom
| | - Liming Ying
- National
Heart and Lung Institute, Imperial College
London, Molecular Sciences Research Hub, London W12 0BZ, United Kingdom
| | - Joshua B. Edel
- Department
of Chemistry, Imperial College London, Molecular
Sciences Research Hub, London W12 0BZ, United
Kingdom
| | - Aleksandar P. Ivanov
- Department
of Chemistry, Imperial College London, Molecular
Sciences Research Hub, London W12 0BZ, United
Kingdom
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33
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Bodily TA, Ramanathan A, Wei S, Karkisaval A, Bhatt N, Jerez C, Haque MA, Ramil A, Heda P, Wang Y, Kumar S, Leite M, Li T, Zhao J, Lal R. In pursuit of degenerative brain disease diagnosis: Dementia biomarkers detected by DNA aptamer-attached portable graphene biosensor. Proc Natl Acad Sci U S A 2023; 120:e2311565120. [PMID: 37956285 PMCID: PMC10666025 DOI: 10.1073/pnas.2311565120] [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: 07/10/2023] [Accepted: 09/25/2023] [Indexed: 11/15/2023] Open
Abstract
Dementia is a brain disease which results in irreversible and progressive loss of cognition and motor activity. Despite global efforts, there is no simple and reliable diagnosis or treatment option. Current diagnosis involves indirect testing of commonly inaccessible biofluids and low-resolution brain imaging. We have developed a portable, wireless readout-based Graphene field-effect transistor (GFET) biosensor platform that can detect viruses, proteins, and small molecules with single-molecule sensitivity and specificity. We report the detection of three important amyloids, namely, Amyloid beta (Aβ), Tau (τ), and α-Synuclein (αS) using DNA aptamer nanoprobes. These amyloids were isolated, purified, and characterized from the autopsied brain tissues of Alzheimer's Disease (AD) and Parkinson's Disease (PD) patients. The limit of detection (LoD) of the sensor is 10 fM, 1-10 pM, 10-100 fM for Aβ, τ, and αS, respectively. Synthetic as well as autopsied brain-derived amyloids showed a statistically significant sensor response with respect to derived thresholds, confirming the ability to define diseased vs. nondiseased states. The detection of each amyloid was specific to their aptamers; Aβ, τ, and αS peptides when tested, respectively, with aptamers nonspecific to them showed statistically insignificant cross-reactivity. Thus, the aptamer-based GFET biosensor has high sensitivity and precision across a range of epidemiologically significant AD and PD variants. This portable diagnostic system would allow at-home and POC testing for neurodegenerative diseases globally.
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Affiliation(s)
| | - Anirudh Ramanathan
- Department of Bioengineering, University of California, San Diego, CA92093
| | - Shanhong Wei
- State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai200050, China
- University of Chinese Academy of Sciences, Beijing100049, China
| | - Abhijith Karkisaval
- Department of Mechanical and Aerospace Engineering, University of California, San Diego, CA92093
| | - Nemil Bhatt
- Mitchell Center for Neurodegenerative Disorders, Department of Neurology, University of Texas Medical Branch, Galveston, TX77555
| | - Cynthia Jerez
- Mitchell Center for Neurodegenerative Disorders, Department of Neurology, University of Texas Medical Branch, Galveston, TX77555
| | - Md Anzarul Haque
- Mitchell Center for Neurodegenerative Disorders, Department of Neurology, University of Texas Medical Branch, Galveston, TX77555
| | - Armando Ramil
- Department of Bioengineering, University of California, San Diego, CA92093
| | - Prachi Heda
- Department of Bioengineering, University of California, San Diego, CA92093
| | - Yi Wang
- State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai200050, China
| | - Sanjeev Kumar
- Department of Computer Science, University of Illinois Urbana-Champaign, Champaign, IL61820
| | - Mikayla Leite
- Department of Bioengineering, University of California, San Diego, CA92093
| | - Tie Li
- State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai200050, China
| | - Jianlong Zhao
- State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai200050, China
| | - Ratnesh Lal
- Department of Bioengineering, University of California, San Diego, CA92093
- Department of Mechanical and Aerospace Engineering, University of California, San Diego, CA92093
- Materials Science and Engineering Program, University of California, San Diego, CA92093
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Reed AL, Mitchell W, Alexandrescu AT, Alder NN. Interactions of amyloidogenic proteins with mitochondrial protein import machinery in aging-related neurodegenerative diseases. Front Physiol 2023; 14:1263420. [PMID: 38028797 PMCID: PMC10652799 DOI: 10.3389/fphys.2023.1263420] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Accepted: 10/02/2023] [Indexed: 12/01/2023] Open
Abstract
Most mitochondrial proteins are targeted to the organelle by N-terminal mitochondrial targeting sequences (MTSs, or "presequences") that are recognized by the import machinery and subsequently cleaved to yield the mature protein. MTSs do not have conserved amino acid compositions, but share common physicochemical properties, including the ability to form amphipathic α-helical structures enriched with basic and hydrophobic residues on alternating faces. The lack of strict sequence conservation implies that some polypeptides can be mistargeted to mitochondria, especially under cellular stress. The pathogenic accumulation of proteins within mitochondria is implicated in many aging-related neurodegenerative diseases, including Alzheimer's, Parkinson's, and Huntington's diseases. Mechanistically, these diseases may originate in part from mitochondrial interactions with amyloid-β precursor protein (APP) or its cleavage product amyloid-β (Aβ), α-synuclein (α-syn), and mutant forms of huntingtin (mHtt), respectively, that are mediated in part through their associations with the mitochondrial protein import machinery. Emerging evidence suggests that these amyloidogenic proteins may present cryptic targeting signals that act as MTS mimetics and can be recognized by mitochondrial import receptors and transported into different mitochondrial compartments. Accumulation of these mistargeted proteins could overwhelm the import machinery and its associated quality control mechanisms, thereby contributing to neurological disease progression. Alternatively, the uptake of amyloidogenic proteins into mitochondria may be part of a protein quality control mechanism for clearance of cytotoxic proteins. Here we review the pathomechanisms of these diseases as they relate to mitochondrial protein import and effects on mitochondrial function, what features of APP/Aβ, α-syn and mHtt make them suitable substrates for the import machinery, and how this information can be leveraged for the development of therapeutic interventions.
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Affiliation(s)
- Ashley L. Reed
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT, United States
| | - Wayne Mitchell
- Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, United States
| | - Andrei T. Alexandrescu
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT, United States
| | - Nathan N. Alder
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT, United States
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Diaw SH, Borsche M, Streubel-Gallasch L, Dulovic-Mahlow M, Hermes J, Lenz I, Seibler P, Klein C, Brüggemann N, Vos M, Lohmann K. Characterization of the pathogenic α-Synuclein Variant V15A in Parkinson´s disease. NPJ Parkinsons Dis 2023; 9:148. [PMID: 37903765 PMCID: PMC10616187 DOI: 10.1038/s41531-023-00584-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Accepted: 10/02/2023] [Indexed: 11/01/2023] Open
Abstract
Despite being a major component of Lewy bodies and Lewy neurites, pathogenic variants in the gene encoding alpha-Synuclein (α-Syn) are rare. To date, only four missense variants in the SNCA gene, encoding α-Syn have unequivocally been shown to be disease-causing. We here describe a Parkinson´s disease patient with early cognitive decline carrying an as yet not fully characterized variant in SNCA (NM_001146055: c.44T > C, p.V15A). We used different cellular models, including stably transfected neuroblastoma (SH-SY5Y) cell cultures, induced pluripotent stem cell (iPSC)-derived neuronal cultures, and generated a Drosophila model to elucidate the impact of the p.V15A variant on α-Syn function and aggregation properties compared to other known pathogenic variants. We demonstrate that p.V15A increased the aggregation potential of α-Syn and the levels of apoptotic markers, and impaired the mitochondrial network. Moreover, p.V15A affects the flying ability and survival of mutant flies. Thus, we provide supporting evidence for the pathogenicity of the p.V15A variant, suggesting its inclusion in genetic testing approaches.
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Affiliation(s)
| | - Max Borsche
- Institute of Neurogenetics, University of Lübeck, 23562, Lübeck, Germany
- Department of Neurology, University Hospital Schleswig Holstein, Lübeck, Germany
| | | | | | - Julia Hermes
- Institute of Neurogenetics, University of Lübeck, 23562, Lübeck, Germany
| | - Insa Lenz
- Institute of Neurogenetics, University of Lübeck, 23562, Lübeck, Germany
| | - Philip Seibler
- Institute of Neurogenetics, University of Lübeck, 23562, Lübeck, Germany
| | - Christine Klein
- Institute of Neurogenetics, University of Lübeck, 23562, Lübeck, Germany
| | - Norbert Brüggemann
- Institute of Neurogenetics, University of Lübeck, 23562, Lübeck, Germany
- Department of Neurology, University Hospital Schleswig Holstein, Lübeck, Germany
| | - Melissa Vos
- Institute of Neurogenetics, University of Lübeck, 23562, Lübeck, Germany
| | - Katja Lohmann
- Institute of Neurogenetics, University of Lübeck, 23562, Lübeck, Germany.
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36
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Zhu W, Neuwirth LS, Cadet P. Regulation of the Endogenous Opiate Signaling Pathway against Oxidative Stress and Inflammation: A Considerable Approach for Exploring Preclinical Treatment of Parkinson's Disease. Pharmacology 2023; 108:550-564. [PMID: 37820589 DOI: 10.1159/000533775] [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: 08/16/2022] [Accepted: 08/22/2023] [Indexed: 10/13/2023]
Abstract
INTRODUCTION Oxidative stress and inflammation are major factors contributing to the progressive death of dopaminergic neurons in Parkinson's disease (PD). Recent studies have demonstrated that morphine's biosynthetic pathway, coupled with nitric oxide (NO) release, is evolutionarily conserved throughout animals and humans. Moreover, dopamine is a key precursor for morphine biosynthesis. METHOD The present study evaluated a series of preclinical experiments to evaluate the effects of low-level morphine treatment upon neuro-immune tissues exposed to rotenone and 6-OHDA as models of PD, followed by an 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide cell proliferation assay and cell/tissue computer-assisted imaging analyses to assess cell/neuronal viability. RESULTS Morphine at normal physiological concentrations (i.e., 10-6 M and 10-7 M) provided neuroprotection, as it significantly inhibited rotenone and 6-OHDA dopaminergic insults; thereby, reducing and/or forestalling cell death in invertebrate ganglia and human nerve cells. To ensure that morphine caused this neuroprotective effect, naloxone, a potent opiate receptor antagonist, was employed and the results showed that it blocked morphine's neuroprotective effects. Additionally, co-incubation of NO synthase inhibitor L-NAME also blocked morphine's neuroprotective effects against rotenone and 6-OHDA insults. CONCLUSIONS Taken together, the present preclinical study showed that while morphine can attenuate lipopolysaccharide-induced inflammation and cell death, both naloxone and L-NAME can abolish this effect. Preincubation of morphine precursors (i.e., L-3,4-dihydroxyphenylalanine, reticuline, and trihexyphenidyl [THP] at physiological concentrations) mimics the observed morphine effect. However, high concentrations of THP, a precursor of the morphine biosynthetic pathway, induced cell death, indicating the physiological importance of morphine biosynthesis in neural tissues. Thus, understanding the morphine biosynthetic pathway coupled with a NO signaling mechanism as a molecular target for neuroprotection against oxidative stress and inflammation in other preclinical models of PD is warranted.
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Affiliation(s)
- Wei Zhu
- SUNY Neuroscience Research Institute (NRI), Old Westbury, New York, USA
- Department of Psychology, SUNY Old Westbury, Old Westbury, New York, USA
- Department of Biology, SUNY Old Westbury, Old Westbury, New York, USA
| | - Lorenz S Neuwirth
- SUNY Neuroscience Research Institute (NRI), Old Westbury, New York, USA
- Department of Psychology, SUNY Old Westbury, Old Westbury, New York, USA
| | - Patrick Cadet
- SUNY Neuroscience Research Institute (NRI), Old Westbury, New York, USA
- Department of Biology, SUNY Old Westbury, Old Westbury, New York, USA
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37
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Roeters SJ, Strunge K, Pedersen KB, Golbek TW, Bregnhøj M, Zhang Y, Wang Y, Dong M, Nielsen J, Otzen DE, Schiøtt B, Weidner T. Elevated concentrations cause upright alpha-synuclein conformation at lipid interfaces. Nat Commun 2023; 14:5731. [PMID: 37723164 PMCID: PMC10507035 DOI: 10.1038/s41467-023-39843-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Accepted: 06/23/2023] [Indexed: 09/20/2023] Open
Abstract
The amyloid aggregation of α-synuclein (αS), related to Parkinson's disease, can be catalyzed by lipid membranes. Despite the importance of lipid surfaces, the 3D-structure and orientation of lipid-bound αS is still not known in detail. Here, we report interface-specific vibrational sum-frequency generation (VSFG) experiments that reveal how monomeric αS binds to an anionic lipid interface over a large range of αS-lipid ratios. To interpret the experimental data, we present a frame-selection method ("ViscaSelect") in which out-of-equilibrium molecular dynamics simulations are used to generate structural hypotheses that are compared to experimental amide-I spectra via excitonic spectral calculations. At low and physiological αS concentrations, we derive flat-lying helical structures as previously reported. However, at elevated and potentially disease-related concentrations, a transition to interface-protruding αS structures occurs. Such an upright conformation promotes lateral interactions between αS monomers and may explain how lipid membranes catalyze the formation of αS amyloids at elevated protein concentrations.
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Affiliation(s)
- Steven J Roeters
- Department of Chemistry, Aarhus University, Langelandsgade 140, 8000, Aarhus C, Denmark.
- Department of Anatomy and Neurosciences, Amsterdam UMC, Vrije Universiteit, De Boelelaan 1108, 1081 HZ, Amsterdam, The Netherlands.
| | - Kris Strunge
- Department of Chemistry, Aarhus University, Langelandsgade 140, 8000, Aarhus C, Denmark
| | - Kasper B Pedersen
- Department of Chemistry, Aarhus University, Langelandsgade 140, 8000, Aarhus C, Denmark
| | - Thaddeus W Golbek
- Department of Chemistry, Aarhus University, Langelandsgade 140, 8000, Aarhus C, Denmark
| | - Mikkel Bregnhøj
- Department of Chemistry, Aarhus University, Langelandsgade 140, 8000, Aarhus C, Denmark
| | - Yuge Zhang
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav Wieds Vej 14, 8000, Aarhus C, Denmark
| | - Yin Wang
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav Wieds Vej 14, 8000, Aarhus C, Denmark
| | - Mingdong Dong
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav Wieds Vej 14, 8000, Aarhus C, Denmark
| | - Janni Nielsen
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav Wieds Vej 14, 8000, Aarhus C, Denmark
| | - Daniel E Otzen
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav Wieds Vej 14, 8000, Aarhus C, Denmark
| | - Birgit Schiøtt
- Department of Chemistry, Aarhus University, Langelandsgade 140, 8000, Aarhus C, Denmark
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav Wieds Vej 14, 8000, Aarhus C, Denmark
| | - Tobias Weidner
- Department of Chemistry, Aarhus University, Langelandsgade 140, 8000, Aarhus C, Denmark.
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38
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Ortigosa-Pascual L, Leiding T, Linse S, Pálmadóttir T. Photo-Induced Cross-Linking of Unmodified α-Synuclein Oligomers. ACS Chem Neurosci 2023; 14:3192-3205. [PMID: 37621159 PMCID: PMC10485903 DOI: 10.1021/acschemneuro.3c00326] [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: 05/12/2023] [Accepted: 08/14/2023] [Indexed: 08/26/2023] Open
Abstract
Photo-induced cross-linking of unmodified proteins (PICUP) has been used in the past to study size distributions of protein assemblies. PICUP may, for example, overcome the significant experimental challenges related to the transient nature, heterogeneity, and low concentration of amyloid protein oligomers relative to monomeric and fibrillar species. In the current study, a reaction chamber was designed, produced, and used for PICUP reaction optimization in terms of reaction conditions and lighting time from ms to s. These efforts make the method more reproducible and accessible and enable the use of shorter reaction times compared to previous studies. We applied the optimized method to an α-synuclein aggregation time course to monitor the relative concentration and size distribution of oligomers over time. The data are compared to the time evolution of the fibril mass concentration, as monitored by thioflavin T fluorescence. At all time points, the smaller the oligomer, the higher its concentration observed after PICUP. Moreover, the total oligomer concentration is highest at short aggregation times, and the decline over time follows the disappearance of monomers. We can therefore conclude that these oligomers form from monomers.
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Affiliation(s)
- Lei Ortigosa-Pascual
- Department of Biochemistry and Structural
Biology, Lund University, 221 00 Lund, Sweden
| | - Thom Leiding
- Department of Biochemistry and Structural
Biology, Lund University, 221 00 Lund, Sweden
| | - Sara Linse
- Department of Biochemistry and Structural
Biology, Lund University, 221 00 Lund, Sweden
| | - Tinna Pálmadóttir
- Department of Biochemistry and Structural
Biology, Lund University, 221 00 Lund, Sweden
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Rocha SM, Kirkley KS, Chatterjee D, Aboellail TA, Smeyne RJ, Tjalkens RB. Microglia-specific knock-out of NF-κB/IKK2 increases the accumulation of misfolded α-synuclein through the inhibition of p62/sequestosome-1-dependent autophagy in the rotenone model of Parkinson's disease. Glia 2023; 71:2154-2179. [PMID: 37199240 PMCID: PMC10330367 DOI: 10.1002/glia.24385] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 05/02/2023] [Accepted: 05/05/2023] [Indexed: 05/19/2023]
Abstract
Parkinson's disease (PD) is the most common neurodegenerative movement disorder worldwide, with a greater prevalence in men than women. The etiology of PD is largely unknown, although environmental exposures and neuroinflammation are linked to protein misfolding and disease progression. Activated microglia are known to promote neuroinflammation in PD, but how environmental agents interact with specific innate immune signaling pathways in microglia to stimulate conversion to a neurotoxic phenotype is not well understood. To determine how nuclear factor kappa B (NF-κB) signaling dynamics in microglia modulate neuroinflammation and dopaminergic neurodegeneration, we generated mice deficient in NF-κB activation in microglia (CX3CR1-Cre::IKK2fl/fl ) and exposed them to 2.5 mg/kg/day of rotenone for 14 days, followed by a 14-day post-lesioning incubation period. We postulated that inhibition of NF-κB signaling in microglia would reduce overall inflammatory injury in lesioned mice. Subsequent analysis indicated decreased expression of the NF-κB-regulated autophagy gene, sequestosome 1 (p62), in microglia, which is required for targeting ubiquitinated α-synuclein (α-syn) for lysosomal degradation. Knock-out animals had increased accumulation of misfolded α-syn within microglia, despite an overall reduction in neurodegeneration. Interestingly, this occurred more prominently in males. These data suggest that microglia play key biological roles in the degradation and clearance of misfolded α-syn and this process works in concert with the innate immune response associated with neuroinflammation. Importantly, the accumulation of misfolded α-syn protein aggregates alone did not increase neurodegeneration following exposure to rotenone but required the NF-κB-dependent inflammatory response in microglia.
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Affiliation(s)
- Savannah M. Rocha
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO 80523
| | - Kelly S. Kirkley
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO 80523
| | - Debotri Chatterjee
- Jefferson Comprehensive Parkinson’s Center, Vickie & Jack Farber Institute for Neuroscience, Thomas Jefferson University, Philadelphia, PA 19107
| | - Tawfik A. Aboellail
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523
| | - Richard J. Smeyne
- Jefferson Comprehensive Parkinson’s Center, Vickie & Jack Farber Institute for Neuroscience, Thomas Jefferson University, Philadelphia, PA 19107
| | - Ronald B. Tjalkens
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO 80523
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40
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de Wet S, Theart R, Loos B. Cogs in the autophagic machine-equipped to combat dementia-prone neurodegenerative diseases. Front Mol Neurosci 2023; 16:1225227. [PMID: 37720551 PMCID: PMC10500130 DOI: 10.3389/fnmol.2023.1225227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Accepted: 07/31/2023] [Indexed: 09/19/2023] Open
Abstract
Neurodegenerative diseases are often characterized by hydrophobic inclusion bodies, and it may be the case that the aggregate-prone proteins that comprise these inclusion bodies are in fact the cause of neurotoxicity. Indeed, the appearance of protein aggregates leads to a proteostatic imbalance that causes various interruptions in physiological cellular processes, including lysosomal and mitochondrial dysfunction, as well as break down in calcium homeostasis. Oftentimes the approach to counteract proteotoxicity is taken to merely upregulate autophagy, measured by an increase in autophagosomes, without a deeper assessment of contributors toward effective turnover through autophagy. There are various ways in which autophagy is regulated ranging from the mammalian target of rapamycin (mTOR) to acetylation status of proteins. Healthy mitochondria and the intracellular energetic charge they preserve are key for the acidification status of lysosomes and thus ensuring effective clearance of components through the autophagy pathway. Both mitochondria and lysosomes have been shown to bear functional protein complexes that aid in the regulation of autophagy. Indeed, it may be the case that minimizing the proteins associated with the respective neurodegenerative pathology may be of greater importance than addressing molecularly their resulting inclusion bodies. It is in this context that this review will dissect the autophagy signaling pathway, its control and the manner in which it is molecularly and functionally connected with the mitochondrial and lysosomal system, as well as provide a summary of the role of autophagy dysfunction in driving neurodegenerative disease as a means to better position the potential of rapamycin-mediated bioactivities to control autophagy favorably.
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Affiliation(s)
- Sholto de Wet
- Department of Physiological Sciences, Stellenbosch University, Stellenbosch, South Africa
| | - Rensu Theart
- Department of Electric and Electronic Engineering, Stellenbosch University, Stellenbosch, South Africa
| | - Ben Loos
- Department of Physiological Sciences, Stellenbosch University, Stellenbosch, South Africa
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Manyilov VD, Ilyinsky NS, Nesterov SV, Saqr BMGA, Dayhoff GW, Zinovev EV, Matrenok SS, Fonin AV, Kuznetsova IM, Turoverov KK, Ivanovich V, Uversky VN. Chaotic aging: intrinsically disordered proteins in aging-related processes. Cell Mol Life Sci 2023; 80:269. [PMID: 37634152 PMCID: PMC11073068 DOI: 10.1007/s00018-023-04897-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Revised: 07/03/2023] [Accepted: 07/24/2023] [Indexed: 08/29/2023]
Abstract
The development of aging is associated with the disruption of key cellular processes manifested as well-established hallmarks of aging. Intrinsically disordered proteins (IDPs) and intrinsically disordered regions (IDRs) have no stable tertiary structure that provide them a power to be configurable hubs in signaling cascades and regulate many processes, potentially including those related to aging. There is a need to clarify the roles of IDPs/IDRs in aging. The dataset of 1702 aging-related proteins was collected from established aging databases and experimental studies. There is a noticeable presence of IDPs/IDRs, accounting for about 36% of the aging-related dataset, which is however less than the disorder content of the whole human proteome (about 40%). A Gene Ontology analysis of the used here aging proteome reveals an abundance of IDPs/IDRs in one-third of aging-associated processes, especially in genome regulation. Signaling pathways associated with aging also contain IDPs/IDRs on different hierarchical levels, revealing the importance of "structure-function continuum" in aging. Protein-protein interaction network analysis showed that IDPs present in different clusters associated with different aging hallmarks. Protein cluster with IDPs enrichment has simultaneously high liquid-liquid phase separation (LLPS) probability, "nuclear" localization and DNA-associated functions, related to aging hallmarks: genomic instability, telomere attrition, epigenetic alterations, and stem cells exhaustion. Intrinsic disorder, LLPS, and aggregation propensity should be considered as features that could be markers of pathogenic proteins. Overall, our analyses indicate that IDPs/IDRs play significant roles in aging-associated processes, particularly in the regulation of DNA functioning. IDP aggregation, which can lead to loss of function and toxicity, could be critically harmful to the cell. A structure-based analysis of aging and the identification of proteins that are particularly susceptible to disturbances can enhance our understanding of the molecular mechanisms of aging and open up new avenues for slowing it down.
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Affiliation(s)
- Vladimir D Manyilov
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Institutskiy Pereulok, 9, Dolgoprudny, 141700, Russia
| | - Nikolay S Ilyinsky
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Institutskiy Pereulok, 9, Dolgoprudny, 141700, Russia.
| | - Semen V Nesterov
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Institutskiy Pereulok, 9, Dolgoprudny, 141700, Russia
- Institute of Cytology, Russian Academy of Sciences, Saint Petersburg, 194064, Russia
| | - Baraa M G A Saqr
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Institutskiy Pereulok, 9, Dolgoprudny, 141700, Russia
| | - Guy W Dayhoff
- Department of Chemistry, University of South Florida, Tampa, FL, USA
| | - Egor V Zinovev
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Institutskiy Pereulok, 9, Dolgoprudny, 141700, Russia
| | - Simon S Matrenok
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Institutskiy Pereulok, 9, Dolgoprudny, 141700, Russia
| | - Alexander V Fonin
- Institute of Cytology, Russian Academy of Sciences, Saint Petersburg, 194064, Russia
| | - Irina M Kuznetsova
- Institute of Cytology, Russian Academy of Sciences, Saint Petersburg, 194064, Russia
| | | | - Valentin Ivanovich
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Institutskiy Pereulok, 9, Dolgoprudny, 141700, Russia
| | - Vladimir N Uversky
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Institutskiy Pereulok, 9, Dolgoprudny, 141700, Russia.
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, 12901 Bruce B. Downs Blvd., MDC07, Tampa, FL, 33612, USA.
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Cordeiro Y, Freire MHO, Wiecikowski AF, do Amaral MJ. (Dys)functional insights into nucleic acids and RNA-binding proteins modulation of the prion protein and α-synuclein phase separation. Biophys Rev 2023; 15:577-589. [PMID: 37681103 PMCID: PMC10480379 DOI: 10.1007/s12551-023-01067-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Accepted: 05/22/2023] [Indexed: 09/09/2023] Open
Abstract
Prion diseases are prototype of infectious diseases transmitted by a protein, the prion protein (PrP), and are still not understandable at the molecular level. Heterogenous species of aggregated PrP can be generated from its monomer. α-synuclein (αSyn), related to Parkinson's disease, has also shown a prion-like pathogenic character, and likewise PrP interacts with nucleic acids (NAs), which in turn modulate their aggregation. Recently, our group and others have characterized that NAs and/or RNA-binding proteins (RBPs) modulate recombinant PrP and/or αSyn condensates formation, and uncontrolled condensation might precede pathological aggregation. Tackling abnormal phase separation of neurodegenerative disease-related proteins has been proposed as a promising therapeutic target. Therefore, understanding the mechanism by which polyanions, like NAs, modulate phase transitions intracellularly, is key to assess their role on toxicity promotion and neuronal death. Herein we discuss data on the nucleic acids binding properties and phase separation ability of PrP and αSyn with a special focus on their modulation by NAs and RBPs. Furthermore, we provide insights into condensation of PrP and/or αSyn in the light of non-trivial subcellular locations such as the nuclear and cytosolic environments.
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Affiliation(s)
- Yraima Cordeiro
- Faculty of Pharmacy, Universidade Federal do Rio de Janeiro, Av Carlos Chagas Filho 373, bloco B, subsolo Sala 36, Rio de Janeiro, RJ 21941-902 Brazil
| | - Maria Heloisa O. Freire
- Faculty of Pharmacy, Universidade Federal do Rio de Janeiro, Av Carlos Chagas Filho 373, bloco B, subsolo Sala 36, Rio de Janeiro, RJ 21941-902 Brazil
| | - Adalgisa Felippe Wiecikowski
- Faculty of Pharmacy, Universidade Federal do Rio de Janeiro, Av Carlos Chagas Filho 373, bloco B, subsolo Sala 36, Rio de Janeiro, RJ 21941-902 Brazil
| | - Mariana Juliani do Amaral
- Faculty of Pharmacy, Universidade Federal do Rio de Janeiro, Av Carlos Chagas Filho 373, bloco B, subsolo Sala 36, Rio de Janeiro, RJ 21941-902 Brazil
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43
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Awasthi S, Ying C, Li J, Mayer M. Simultaneous Determination of the Size and Shape of Single α-Synuclein Oligomers in Solution. ACS NANO 2023; 17:12325-12335. [PMID: 37327131 PMCID: PMC10339783 DOI: 10.1021/acsnano.3c01393] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 06/06/2023] [Indexed: 06/18/2023]
Abstract
Soluble oligomers of amyloid-forming proteins are implicated as toxic species in the context of several neurodegenerative diseases. Since the size and shape of these oligomers influence their toxicity, their biophysical characterization is essential for a better understanding of the structure-toxicity relationship. Amyloid oligomers are difficult to characterize by conventional approaches due to their heterogeneity in size and shape, their dynamic aggregation process, and their low abundance. This work demonstrates that resistive pulse measurements using polymer-coated solid-state nanopores enable single-particle-level characterization of the size and shape of individual αSyn oligomers in solution within minutes. A comparison of the resulting size distribution with single-particle analysis by transmission electron microscopy and mass photometry reveals good agreement with superior resolution by nanopore-based characterization. Moreover, nanopore-based analysis has the capability to combine rapid size analysis with an approximation of the oligomer shape. Applying this shape approximation to putatively toxic oligomeric species that range in size from 18 ± 7 aggregated monomers (10S) to 29 ± 10 aggregated monomers (15S) and in concentration from picomolar to nanomolar revealed oligomer shapes that agree well with previous estimates by cryo-EM with the added advantage that nanopore-based analysis occurs rapidly, in solution, and has the potential to become a widely accessible technique.
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Affiliation(s)
- Saurabh Awasthi
- Adolphe
Merkle Institute, University of Fribourg, Chemin des Verdiers 4, CH-1700 Fribourg, Switzerland
| | - Cuifeng Ying
- Adolphe
Merkle Institute, University of Fribourg, Chemin des Verdiers 4, CH-1700 Fribourg, Switzerland
| | - Jiali Li
- University
of Arkansas, Fayetteville, Arkansas 72701, United States
| | - Michael Mayer
- Adolphe
Merkle Institute, University of Fribourg, Chemin des Verdiers 4, CH-1700 Fribourg, Switzerland
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Martinez-Banaclocha MA. Targeting the Cysteine Redox Proteome in Parkinson's Disease: The Role of Glutathione Precursors and Beyond. Antioxidants (Basel) 2023; 12:1373. [PMID: 37507913 PMCID: PMC10376658 DOI: 10.3390/antiox12071373] [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] [Received: 06/03/2023] [Revised: 06/22/2023] [Accepted: 06/28/2023] [Indexed: 07/30/2023] Open
Abstract
Encouraging recent data on the molecular pathways underlying aging have identified variants and expansions of genes associated with DNA replication and repair, telomere and stem cell maintenance, regulation of the redox microenvironment, and intercellular communication. In addition, cell rejuvenation requires silencing some transcription factors and the activation of pluripotency, indicating that hidden molecular networks must integrate and synchronize all these cellular mechanisms. Therefore, in addition to gene sequence expansions and variations associated with senescence, the optimization of transcriptional regulation and protein crosstalk is essential. The protein cysteinome is crucial in cellular regulation and plays unexpected roles in the aging of complex organisms, which show cumulative somatic mutations, telomere attrition, epigenetic modifications, and oxidative dysregulation, culminating in cellular senescence. The cysteine thiol groups are highly redox-active, allowing high functional versatility as structural disulfides, redox-active disulfides, active-site nucleophiles, proton donors, and metal ligands to participate in multiple regulatory sites in proteins. Also, antioxidant systems control diverse cellular functions, including the transcription machinery, which partially depends on the catalytically active cysteines that can reduce disulfide bonds in numerous target proteins, driving their biological integration. Since we have previously proposed a fundamental role of cysteine-mediated redox deregulation in neurodegeneration, we suggest that cellular rejuvenation of the cysteine redox proteome using GSH precursors, like N-acetyl-cysteine, is an underestimated multitarget therapeutic approach that would be particularly beneficial in Parkinson's disease.
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Di Bartolo AL, Caparotta M, Masone D. Intrinsic Disorder in α-Synuclein Regulates the Exocytotic Fusion Pore Transition. ACS Chem Neurosci 2023. [PMID: 37192400 DOI: 10.1021/acschemneuro.3c00040] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/18/2023] Open
Abstract
Today, it is widely accepted that intrinsic disorder is strongly related to the cell cycle, during mitosis, differentiation, and apoptosis. Of particular interest are hybrid proteins possessing both structured and unstructured domains that are critical in human health and disease, such as α-synuclein. In this work, we describe how α-synuclein interacts with the nascent fusion pore as it evolves toward expansion. We unveil the key role played by its intrinsically disordered region as a thermodynamic regulator of the nucleation-expansion energy barrier. By analyzing a truncated variant of α-synuclein that lacks the disordered region, we find that the landscape of protein interactions with PIP2 and POPS lipids is highly altered, ultimately increasing the energy cost for the fusion pore to transit from nucleation to expansion. We conclude that the intrinsically disordered region in full-length α-synuclein recognizes and allocates pivotal protein:lipid interactions during membrane remodeling in the first stages of the fusion pore.
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Affiliation(s)
- Ary Lautaro Di Bartolo
- Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo (UNCuyo), 5500 Mendoza, Argentina
| | - Marcelo Caparotta
- Quantum Theory Project, Department of Chemistry, University of Florida, Gainesville, Florida 32611, United States
| | - Diego Masone
- Instituto de Histología y Embriología de Mendoza (IHEM) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Cuyo (UNCuyo), 5500 Mendoza, Argentina
- Facultad de Ingeniería, Universidad Nacional de Cuyo (UNCuyo), 5500 Mendoza, Argentina
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46
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Nuzum ND, Szymlek-Gay EA, Loke S, Dawson SL, Teo WP, Hendy AM, Loughman A, Macpherson H. Differences in the gut microbiome across typical ageing and in Parkinson's disease. Neuropharmacology 2023; 235:109566. [PMID: 37150399 DOI: 10.1016/j.neuropharm.2023.109566] [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: 12/22/2022] [Revised: 04/21/2023] [Accepted: 04/30/2023] [Indexed: 05/09/2023]
Abstract
The microbiota-gut-brain axis' role in Parkinson's disease (PD) pathophysiology, and how this differs from typical ageing, is poorly understood. Presently, gut-bacterial diversity, taxonomic abundance and metabolic bacterial pathways were compared across healthy young (n = 22, 18-35 years), healthy older (n = 33, 50-80 years), and PD groups (n = 18, 50-80 years) using shotgun sequencing and compositional data analysis. Associations between the gut-microbiome and PD symptoms, and between lifestyle factors (fibre intake, physical activity, and sleep) and the gut-microbiome were conducted. Alpha-diversity did not differ between PD participants and older adults, whilst beta-diversity differed between these groups. Lower abundance of Butyricimonas synergistica, a butyrate-producer, was associated with worse PD non-motor symptoms in the PD group. Regarding typical ageing, Bifidobacterium bifidum, was greater in the younger compared to older group, with no difference between the older and PD group. Abundance of metabolic pathways related to butyrate production did not differ among the groups, while 100 other metabolic pathways differed among the three groups. Sleep efficiency was positively associated with Roseburia inulinivorans in the older group. These results highlight the relevance of gut-microbiota to PD and that reduced butyrate-production may be involved with PD pathophysiology. Future studies should account for lifestyle factors when investigating gut-microbiomes across ageing and in PD.
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Affiliation(s)
- Nathan D Nuzum
- Deakin University, Institute for Physical Activity and Nutrition (IPAN), School of Exercise and Nutrition Sciences, Geelong, Australia.
| | - Ewa A Szymlek-Gay
- Deakin University, Institute for Physical Activity and Nutrition (IPAN), School of Exercise and Nutrition Sciences, Geelong, Australia
| | - Stella Loke
- Deakin University, School of Life and Environmental Sciences, Australia
| | - Samantha L Dawson
- Deakin University, Food & Mood Centre, IMPACT Strategic Research Centre, School of Medicine, Geelong, Australia
| | - Wei-Peng Teo
- Physical Education and Sports Science Academic Group, National Institute of Education, Nanyang Technological University, Singapore
| | - Ashlee M Hendy
- Deakin University, Institute for Physical Activity and Nutrition (IPAN), School of Exercise and Nutrition Sciences, Geelong, Australia
| | - Amy Loughman
- Deakin University, Food & Mood Centre, IMPACT Strategic Research Centre, School of Medicine, Geelong, Australia
| | - Helen Macpherson
- Deakin University, Institute for Physical Activity and Nutrition (IPAN), School of Exercise and Nutrition Sciences, Geelong, Australia
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Menon S, Mondal J. Conformational Plasticity in α-Synuclein and How Crowded Environment Modulates It. J Phys Chem B 2023; 127:4032-4049. [PMID: 37114769 DOI: 10.1021/acs.jpcb.3c00982] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
A 140-residue intrinsically disordered protein (IDP), α-synuclein (αS), is known to adopt conformations that are vastly plastic and susceptible to environmental cues and crowders. However, the inherently heterogeneous nature of αS has precluded a clear demarcation of its monomeric precursor between aggregation-prone and functionally relevant aggregation-resistant states and how a crowded environment could modulate their mutual dynamic equilibrium. Here, we identify an optimal set of distinct metastable states of αS in aqueous media by dissecting a 73 μs-long molecular dynamics ensemble via building a comprehensive Markov state model (MSM). Notably, the most populated metastable state corroborates with the dimension obtained from PRE-NMR studies of αS monomer, and it undergoes kinetic transition at diverse time scales with a weakly populated random-coil-like ensemble and a globular protein-like state. However, subjecting αS to a crowded environment results in a nonmonotonic compaction of these metastable conformations, thereby skewing the ensemble by either introducing new tertiary contacts or by reinforcing the innate contacts. The early stage of dimerization process is found to be considerably expedited in the presence of crowders, albeit promoting nonspecific interactions. Together with this, using an extensively sampled ensemble of αS, this exposition demonstrates that crowded environments can potentially modulate the conformational preferences of IDP that can either promote or inhibit aggregation events.
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Affiliation(s)
- Sneha Menon
- Tata Institute of Fundamental Research Hyderabad, Telangana 500046, India
| | - Jagannath Mondal
- Tata Institute of Fundamental Research Hyderabad, Telangana 500046, India
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Mazzotta GM, Ceccato N, Conte C. Synucleinopathies Take Their Toll: Are TLRs a Way to Go? Cells 2023; 12:cells12091231. [PMID: 37174631 PMCID: PMC10177040 DOI: 10.3390/cells12091231] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 04/17/2023] [Accepted: 04/22/2023] [Indexed: 05/15/2023] Open
Abstract
The misfolding and subsequent abnormal accumulation and aggregation of α-Synuclein (αSyn) as insoluble fibrils in Lewy bodies and Lewy neurites is the pathological hallmark of Parkinson's disease (PD) and several neurodegenerative disorders. A combination of environmental and genetic factors is linked to αSyn misfolding, among which neuroinflammation is recognized to play an important role. Indeed, a number of studies indicate that a Toll-like receptor (TLR)-mediated neuroinflammation might lead to a dopaminergic neural loss, suggesting that TLRs could participate in the pathogenesis of PD as promoters of immune/neuroinflammatory responses. Here we will summarize our current understanding on the mechanisms of αSyn aggregation and misfolding, focusing on the contribution of TLRs to the progression of α-synucleinopathies and speculating on their link with the non-motor disturbances associated with aging and neurodegenerative disorders.
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Affiliation(s)
| | - Nadia Ceccato
- Department of Biology, University of Padova, 35131 Padova, Italy
| | - Carmela Conte
- Department of Pharmaceutical Sciences, University of Perugia, 06100 Perugia, Italy
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Kumari K, Sharma GS, Gupta A, Singh KS, Singh LR. Functionally active cross-linked protein oligomers formed by homocysteine thiolactone. Sci Rep 2023; 13:5620. [PMID: 37024663 PMCID: PMC10079695 DOI: 10.1038/s41598-023-32694-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 03/31/2023] [Indexed: 04/08/2023] Open
Abstract
Deposition of high-order protein oligomers is a common hallmark of a large number of human diseases and therefore, has been of immense medical interest. From the past several decades, efforts are being made to characterize protein oligomers and explore how they are linked with the disease pathologies. In general, oligomers are non-functional, rather cytotoxic in nature while the functional (non-cytotoxic) oligomers are quite rare. In the present study, we identified new protein oligomers of Ribonuclease-A and Lysozyme that contain functionally active fractions. These functional oligomers are disulfide cross-linked, native-like, and obtained as a result of the covalent modification of the proteins by the toxic metabolite, homocysteine thiolactone accumulated under hyperhomocysteinemia (a condition responsible for cardiovascular complications including atherosclerosis). These results have been obtained from the extensive analysis of the nature of oligomers, functional status, and structural integrity of the proteins using orthogonal techniques. The study implicates the existence of such oligomers as protein sinks that may sequester toxic homocysteines in humans.
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Affiliation(s)
- Kritika Kumari
- Dr. B. R. Ambedkar Center for Biomedical Research, University of Delhi, Delhi, 110007, India
| | - Gurumayum Suraj Sharma
- Department of Botany, Bhaskaracharya College of Applied Sciences, University of Delhi, New Delhi, 110075, India
| | - Akshita Gupta
- Dr. B. R. Ambedkar Center for Biomedical Research, University of Delhi, Delhi, 110007, India
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Verma G, Bhat R. The Anthocyanidin Peonidin Interferes with an Early Step in the Fibrillation Pathway of α-Synuclein and Modulates It toward Amorphous Aggregates. ACS Chem Neurosci 2023. [PMID: 37011370 DOI: 10.1021/acschemneuro.2c00726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2023] Open
Abstract
Parkinson's disease (PD) is characterized by progressive degeneration of the dopaminergic neurons in the brain, accompanied by the accumulation of proteinaceous inclusions, Lewy bodies (LB), mainly comprised of alpha synuclein (α-syn) aggregates. The heterogeneity and the transient nature of the intermediate species formed in the α-syn fibrillation pathway have made it difficult to develop an effective therapeutic intervention. Therefore, any therapeutic molecule that could prevent as well as treat PD would be of great interest. Anthocyanidins are natural flavonoid compounds that have been shown to have neuroprotective properties and to modulate factors that cause neuronal death. Herein, we have explored the modulation and inhibition of α-syn fibrillation by the anthocyanidins cyanidin, delphinidin, and peonidin using a number of biophysical and structural tools. α-Syn fibrillation monitored using thioflavin T (ThT) fluorescence and light scattering suggested concentration dependent inhibition of α-syn fibrillation by all the three anthocyanidins. While cyanidin and delphinidin induced the formation of oligomers and small fibrillar structures of α-syn, respectively, peonidin led to the formation of amorphous aggregates, as observed by Atomic Force Microscopy (AFM). Peonidin proved to be most effective of the three anthocyanidins toward alleviating cell toxicity of SH-SY5Y neuroblastoma cells at concentrations where α-synuclein fibrillation was completely suppressed. Hence, the inhibition mechanism of peonidin was further explored by studying its interaction with α-syn using titration calorimetry and molecular docking. The results show its weak binding (in mM range) to the NAC region of α-syn through hydrogen bonding interactions. Also, circular dichroism and Raman spectroscopy revealed the structural aspects of peonidin-induced α-syn amorphous aggregates showing alpha helical structures with exposed Phe and Tyr regions. Due to the neuroprotective nature of peonidin, the findings reported here are significant and can be further explored toward developing a modifying therapy that could address both disease onset as well as the progression of PD.
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Affiliation(s)
- Geetika Verma
- School of Biotechnology Jawaharlal Nehru University, New Delhi 110067, India
| | - Rajiv Bhat
- School of Biotechnology Jawaharlal Nehru University, New Delhi 110067, India
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