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Hamidpour SK, Amiri M, Ketabforoush AHME, Saeedi S, Angaji A, Tavakol S. Unraveling Dysregulated Cell Signaling Pathways, Genetic and Epigenetic Mysteries of Parkinson's Disease. Mol Neurobiol 2024:10.1007/s12035-024-04128-1. [PMID: 38573414 DOI: 10.1007/s12035-024-04128-1] [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: 12/16/2023] [Accepted: 03/19/2024] [Indexed: 04/05/2024]
Abstract
Parkinson's disease (PD) is a prevalent and burdensome neurodegenerative disorder that has been extensively researched to understand its complex etiology, diagnosis, and treatment. The interplay between genetic and environmental factors in PD makes its pathophysiology difficult to comprehend, emphasizing the need for further investigation into genetic and epigenetic markers involved in the disease. Early diagnosis is crucial for optimal management of the disease, and the development of novel diagnostic biomarkers is ongoing. Although many efforts have been made in the field of recognition and interpretation of the mechanisms involved in the pathophysiology of the disease, the current knowledge about PD is just the tip of the iceberg. By scrutinizing genetic and epigenetic patterns underlying PD, new avenues can be opened for dissecting the pathology of the disorder, leading to more precise and efficient diagnostic and therapeutic approaches. This review emphasizes the importance of studying dysregulated cell signaling pathways and molecular processes associated with genes and epigenetic alterations in understanding PD, paving the way for the development of novel therapeutic strategies to combat this devastating disease.
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Affiliation(s)
- Shayesteh Kokabi Hamidpour
- Department of Cell and Molecular Biology, Faculty of Biological Science, Kharazmi University, Tehran, Iran
| | - Mobina Amiri
- Department of Cell and Molecular Biology, Faculty of Biological Science, Kharazmi University, Tehran, Iran
| | | | - Saeedeh Saeedi
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, NE, USA
| | - Abdolhamid Angaji
- Department of Cell and Molecular Biology, Faculty of Biological Science, Kharazmi University, Tehran, Iran
| | - Shima Tavakol
- Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, 1449614535, Iran.
- Department of Research and Development, Tavakol BioMimetic Technologies Company, Tehran, Iran.
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Banerjee R, Raj A, Potdar C, Kumar Pal P, Yadav R, Kamble N, Holla V, Datta I. Astrocytes Differentiated from LRRK2-I1371V Parkinson's-Disease-Induced Pluripotent Stem Cells Exhibit Similar Yield but Cell-Intrinsic Dysfunction in Glutamate Uptake and Metabolism, ATP Generation, and Nrf2-Mediated Glutathione Machinery. Cells 2023; 12:1592. [PMID: 37371062 DOI: 10.3390/cells12121592] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 05/27/2023] [Accepted: 06/06/2023] [Indexed: 06/29/2023] Open
Abstract
Owing to the presence of multiple enzymatic domains, LRRK2 has been associated with a diverse set of cellular functions and signaling pathways. It also has several pathological mutant-variants, and their incidences show ethnicity biases and drug-response differences with expression in dopaminergic-neurons and astrocytes. Here, we aimed to assess the cell-intrinsic effect of the LRRK2-I1371V mutant variant, prevalent in East Asian populations, on astrocyte yield and biology, involving Nrf2-mediated glutathione machinery, glutamate uptake and metabolism, and ATP generation in astrocytes derived from LRRK2-I1371V PD patient iPSCs and independently confirmed in LRRK2-I1371V-overexpressed U87 cells. Astrocyte yield (GFAP-immunopositive) was comparable between LRRK2-I1371V and healthy control (HC) populations; however, the astrocytic capability to mitigate oxidative stress in terms of glutathione content was significantly reduced in the mutant astrocytes, along with a reduction in the gene expression of the enzymes involved in glutathione machinery and nuclear factor erythroid 2-related factor 2 (Nrf2) expression. Simultaneously, a significant decrease in glutamate uptake was observed in LRRK2-I1371V astrocytes, with lower gene expression of glutamate transporters SLC1A2 and SLC1A3. The reduction in the protein expression of SLC1A2 was also directly confirmed. Enzymes catalyzing the generation of γ glutamyl cysteine (precursor of glutathione) from glutamate and the metabolism of glutamate to enter the Krebs cycle (α-ketoglutaric acid) were impaired, with significantly lower ATP generation in LRRK2-I1371V astrocytes. De novo glutamine synthesis via the conversion of glutamate to glutamine was also affected, indicating glutamate metabolism disorder. Our data demonstrate for the first time that the mutation in the LRRK2-I1371V allele causes significant astrocytic dysfunction with respect to Nrf2-mediated antioxidant machinery, AT -generation, and glutamate metabolism, even with comparable astrocyte yields.
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Affiliation(s)
- Roon Banerjee
- Department of Biophysics, National Institute of Mental Health and Neurosciences, Institute of National Importance, Bengaluru 560029, Karnataka, India
| | - Aishwarya Raj
- Department of Biophysics, National Institute of Mental Health and Neurosciences, Institute of National Importance, Bengaluru 560029, Karnataka, India
| | - Chandrakanta Potdar
- Department of Biophysics, National Institute of Mental Health and Neurosciences, Institute of National Importance, Bengaluru 560029, Karnataka, India
| | - Pramod Kumar Pal
- Department of Neurology, National Institute of Mental Health and Neurosciences, Institute of National Importance, Bengaluru 560029, Karnataka, India
| | - Ravi Yadav
- Department of Neurology, National Institute of Mental Health and Neurosciences, Institute of National Importance, Bengaluru 560029, Karnataka, India
| | - Nitish Kamble
- Department of Neurology, National Institute of Mental Health and Neurosciences, Institute of National Importance, Bengaluru 560029, Karnataka, India
| | - Vikram Holla
- Department of Neurology, National Institute of Mental Health and Neurosciences, Institute of National Importance, Bengaluru 560029, Karnataka, India
| | - Indrani Datta
- Department of Biophysics, National Institute of Mental Health and Neurosciences, Institute of National Importance, Bengaluru 560029, Karnataka, India
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Burgunder JM. Mechanisms underlying phenotypic variation in neurogenetic disorders. Nat Rev Neurol 2023:10.1038/s41582-023-00811-4. [PMID: 37202496 DOI: 10.1038/s41582-023-00811-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/12/2023] [Indexed: 05/20/2023]
Abstract
Neurological diseases associated with pathogenic variants in a specific gene, or even with a specific pathogenic variant, can show profound phenotypic variation with regard to symptom presentation, age at onset and disease course. Highlighting examples from a range of neurogenetic disorders, this Review explores emerging mechanisms that are involved in this variability, including environmental, genetic and epigenetic factors that influence the expressivity and penetrance of pathogenic variants. Environmental factors, some of which can potentially be modified to prevent disease, include trauma, stress and metabolic changes. Dynamic patterns of pathogenic variants might explain some of the phenotypic variations, for example, in the case of disorders caused by DNA repeat expansions such as Huntington disease (HD). An important role for modifier genes has also been identified in some neurogenetic disorders, including HD, spinocerebellar ataxia and X-linked dystonia-parkinsonism. In other disorders, such as spastic paraplegia, the basis for most of the phenotypic variability remains unclear. Epigenetic factors have been implicated in disorders such as SGCE-related myoclonus-dystonia and HD. Knowledge of the mechanisms underlying phenotypic variation is already starting to influence management strategies and clinical trials for neurogenetic disorders.
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Ito G, Utsunomiya-Tate N. Overview of the Impact of Pathogenic LRRK2 Mutations in Parkinson's Disease. Biomolecules 2023; 13:biom13050845. [PMID: 37238714 DOI: 10.3390/biom13050845] [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: 03/08/2023] [Revised: 04/25/2023] [Accepted: 05/15/2023] [Indexed: 05/28/2023] Open
Abstract
Leucine-rich repeat kinase 2 (LRRK2) is a large protein kinase that physiologically phosphorylates and regulates the function of several Rab proteins. LRRK2 is genetically implicated in the pathogenesis of both familial and sporadic Parkinson's disease (PD), although the underlying mechanism is not well understood. Several pathogenic mutations in the LRRK2 gene have been identified, and in most cases the clinical symptoms that PD patients with LRRK2 mutations develop are indistinguishable from those of typical PD. However, it has been shown that the pathological manifestations in the brains of PD patients with LRRK2 mutations are remarkably variable when compared to sporadic PD, ranging from typical PD pathology with Lewy bodies to nigral degeneration with deposition of other amyloidogenic proteins. The pathogenic mutations in LRRK2 are also known to affect the functions and structure of LRRK2, the differences in which may be partly attributable to the variations observed in patient pathology. In this review, in order to help researchers unfamiliar with the field to understand the mechanism of pathogenesis of LRRK2-associated PD, we summarize the clinical and pathological manifestations caused by pathogenic mutations in LRRK2, their impact on the molecular function and structure of LRRK2, and their historical background.
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Affiliation(s)
- Genta Ito
- Department of Biomolecular Chemistry, Faculty of Pharma-Sciences, Teikyo University, Tokyo 173-8605, Japan
| | - Naoko Utsunomiya-Tate
- Department of Biomolecular Chemistry, Faculty of Pharma-Sciences, Teikyo University, Tokyo 173-8605, Japan
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Yahya V, Di Fonzo A, Monfrini E. Genetic Evidence for Endolysosomal Dysfunction in Parkinson’s Disease: A Critical Overview. Int J Mol Sci 2023; 24:ijms24076338. [PMID: 37047309 PMCID: PMC10094484 DOI: 10.3390/ijms24076338] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 03/23/2023] [Accepted: 03/26/2023] [Indexed: 03/30/2023] Open
Abstract
Parkinson’s disease (PD) is the second most common neurodegenerative disorder in the aging population, and no disease-modifying therapy has been approved to date. The pathogenesis of PD has been related to many dysfunctional cellular mechanisms, however, most of its monogenic forms are caused by pathogenic variants in genes involved in endolysosomal function (LRRK2, VPS35, VPS13C, and ATP13A2) and synaptic vesicle trafficking (SNCA, RAB39B, SYNJ1, and DNAJC6). Moreover, an extensive search for PD risk variants revealed strong risk variants in several lysosomal genes (e.g., GBA1, SMPD1, TMEM175, and SCARB2) highlighting the key role of lysosomal dysfunction in PD pathogenesis. Furthermore, large genetic studies revealed that PD status is associated with the overall “lysosomal genetic burden”, namely the cumulative effect of strong and weak risk variants affecting lysosomal genes. In this context, understanding the complex mechanisms of impaired vesicular trafficking and dysfunctional endolysosomes in dopaminergic neurons of PD patients is a fundamental step to identifying precise therapeutic targets and developing effective drugs to modify the neurodegenerative process in PD.
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Affiliation(s)
- Vidal Yahya
- Dino Ferrari Center, Department of Pathophysiology and Transplantation, University of Milan, 20122 Milan, Italy;
- Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Neurology Unit, 20122 Milan, Italy;
| | - Alessio Di Fonzo
- Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Neurology Unit, 20122 Milan, Italy;
| | - Edoardo Monfrini
- Dino Ferrari Center, Department of Pathophysiology and Transplantation, University of Milan, 20122 Milan, Italy;
- Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Neurology Unit, 20122 Milan, Italy;
- Correspondence:
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Mata I, Salles P, Cornejo-Olivas M, Saffie P, Ross OA, Reed X, Bandres-Ciga S. LRRK2: Genetic mechanisms vs genetic subtypes. HANDBOOK OF CLINICAL NEUROLOGY 2023; 193:133-154. [PMID: 36803807 DOI: 10.1016/b978-0-323-85555-6.00018-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
In 2004, the identification of pathogenic variants in the LRRK2 gene across several families with autosomal dominant late-onset Parkinson's disease (PD) revolutionized our understanding of the role of genetics in PD. Previous beliefs that genetics in PD was limited to rare early-onset or familial forms of the disease were quickly dispelled. Currently, we recognize LRRK2 p.G2019S as the most common genetic cause of both sporadic and familial PD, with more than 100,000 affected carriers across the globe. The frequency of LRRK2 p.G2019S is also highly variable across populations, with some regions of Asian or Latin America reporting close to 0%, contrasting to Ashkenazi Jews or North African Berbers reporting up to 13% and 40%, respectively. Patients with LRRK2 pathogenic variants are clinically and pathologically heterogeneous, highlighting the age-related variable penetrance that also characterizes LRRK2-related disease. Indeed, the majority of patients with LRRK2-related disease are characterized by a relatively mild Parkinsonism with less motor symptoms with variable presence of α-synuclein and/or tau aggregates, with pathologic pleomorphism widely described. At a functional cellular level, it is likely that pathogenic variants mediate a toxic gain-of-function of the LRRK2 protein resulting in increased kinase activity perhaps in a cell-specific manner; by contrast, some LRRK2 variants appear to be protective reducing PD risk by decreasing the kinase activity. Therefore, employing this information to define appropriate patient populations for clinical trials of targeted kinase LRRK2 inhibition strategies is very promising and demonstrates a potential future application for PD using precision medicine.
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Affiliation(s)
- Ignacio Mata
- Genomic Medicine Institute (GMI), Cleveland Clinic, Cleveland, OH, United States.
| | - Philippe Salles
- Corporación Centro de Trastornos del Movimiento (CETRAM), Lo Espejo, Santiago, Chile
| | - Mario Cornejo-Olivas
- Neurogenetics Research Center, Instituto Nacional de Ciencias Neurológicas, Lima, Peru
| | - Paula Saffie
- Corporación Centro de Trastornos del Movimiento (CETRAM), Lo Espejo, Santiago, Chile
| | - Owen A Ross
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, United States
| | - Xylena Reed
- Laboratory of Neurogenetics, National Institute on Aging, National Institutes of Health, Bethesda, MD, United States
| | - Sara Bandres-Ciga
- Laboratory of Neurogenetics and Center for Alzheimer's and Related Dementias, National Institute on Aging, National Institutes of Health, Bethesda, MD, United States
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LRRK2 and Proteostasis in Parkinson's Disease. Int J Mol Sci 2022; 23:ijms23126808. [PMID: 35743250 PMCID: PMC9224256 DOI: 10.3390/ijms23126808] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 06/16/2022] [Accepted: 06/17/2022] [Indexed: 02/01/2023] Open
Abstract
Parkinson’s disease is a neurodegenerative condition initially characterized by the presence of tremor, muscle stiffness and impaired balance, with the deposition of insoluble protein aggregates in Lewy’s Bodies the histopathological hallmark of the disease. Although different gene variants are linked to Parkinson disease, mutations in the Leucine-Rich Repeat Kinase 2 (LRRK2) gene are one of the most frequent causes of Parkinson’s disease related to genetic mutations. LRRK2 toxicity has been mainly explained by an increase in kinase activity, but alternative mechanisms have emerged as underlying causes for Parkinson’s disease, such as the imbalance in LRRK2 homeostasis and the involvement of LRRK2 in aggregation and spreading of α-synuclein toxicity. In this review, we recapitulate the main LRRK2 pathological mutations that contribute to Parkinson’s disease and the different cellular and therapeutic strategies devised to correct LRRK2 homeostasis. In this review, we describe the main cellular control mechanisms that regulate LRRK2 folding and aggregation, such as the chaperone network and the protein-clearing pathways such as the ubiquitin–proteasome system and the autophagic-lysosomal pathway. We will also address the more relevant strategies to modulate neurodegeneration in Parkinson’s disease through the regulation of LRRK2, using small molecules or LRRK2 silencing.
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8
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Hobson DE, Del Bigio MR. Beekeeper Parkinsonism. Mov Disord 2022; 37:1573-1574. [PMID: 35638319 DOI: 10.1002/mds.29076] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 03/21/2022] [Accepted: 03/22/2022] [Indexed: 12/19/2022] Open
Affiliation(s)
- Douglas E Hobson
- Department of Medicine, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Marc R Del Bigio
- Department of Pathology, University of Manitoba, Winnipeg, Manitoba, Canada
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Dopamine Transporter, PhosphoSerine129 α-Synuclein and α-Synuclein Levels in Aged LRRK2 G2019S Knock-In and Knock-Out Mice. Biomedicines 2022; 10:biomedicines10040881. [PMID: 35453631 PMCID: PMC9027615 DOI: 10.3390/biomedicines10040881] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 04/07/2022] [Accepted: 04/09/2022] [Indexed: 02/04/2023] Open
Abstract
The G2019S mutation in leucine rich-repeat kinase 2 (LRRK2) is a major cause of familial Parkinson’s disease. We previously reported that G2019S knock-in mice manifest dopamine transporter dysfunction and phosphoSerine129 α-synuclein (pSer129 α-syn) immunoreactivity elevation at 12 months of age, which might represent pathological events leading to neuronal degeneration. Here, the time-dependence of these changes was monitored in the striatum of 6, 9, 12, 18 and 23-month-old G2019S KI mice and wild-type controls using DA uptake assay, Western analysis and immunohistochemistry. Western analysis showed elevation of membrane dopamine transporter (DAT) levels at 9 and 12 months of age, along with a reduction of vesicular monoamine transporter 2 (VMAT2) levels at 12 months. DAT uptake was abnormally elevated from 9 to up to 18 months. DAT and VMAT2 level changes were specific to the G2019S mutation since they were not observed in LRRK2 kinase-dead or knock-out mice. Nonetheless, dysfunctional DAT uptake was not normalized by acute pharmacological inhibition of LRRK2 kinase activity with MLi-2. Immunoblot analysis showed elevation of pSer129 α-syn levels in the striatum of 12-month-old G2019S KI mice, which, however, was not confirmed by immunohistochemical analysis. Instead, total α-syn immunoreactivity was found elevated in the striatum of 23-month-old LRRK2 knock-out mice. These data indicate mild changes in DA transporters and α-syn metabolism in the striatum of 12-month-old G2019S KI mice whose pathological relevance remains to be established.
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Genetics of cognitive dysfunction in Parkinson's disease. PROGRESS IN BRAIN RESEARCH 2022; 269:195-226. [PMID: 35248195 DOI: 10.1016/bs.pbr.2022.01.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Presentation and progression of cognitive symptoms in Parkinson's disease are highly variable. PD is a genetically complex disorder with multiple genetic risk factors and understanding the role that genes play in cognitive outcomes is important for patient counseling and treatment. Currently, there are seven well-described genes that increase the risk for PD, with variable levels of penetrance: SNCA, LRRK2, VPS35, PRKN, PINK1, DJ1 and GBA. In addition, large, genome-wide association studies have identified multiple loci in our DNA which increase PD risk. In this chapter, we summarize what is currently known about each of the seven strongly-associated PD genes and select PD risk variants, including PITX3, TMEM106B, SNCA Rep1, APOɛ4, COMT and MAPT H1/H1, along with their respective relationships to cognition.
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11
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LRRK2 signaling in neurodegeneration: two decades of progress. Essays Biochem 2021; 65:859-872. [PMID: 34897411 DOI: 10.1042/ebc20210013] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 11/13/2021] [Accepted: 11/23/2021] [Indexed: 12/17/2022]
Abstract
Leucine-rich repeat kinase 2 (LRRK2) is a complex GTPase/kinase orchestrating cytoskeletal dynamics and multiple steps of the endolysosomal pathway through interaction with a host of partners and phosphorylation of a subset of Rab GTPases. Mutations in LRRK2 cause late-onset Parkinson's disease (PD) and common variants in the locus containing LRRK2 have been associated with sporadic PD, progressive supranuclear palsy as well as a number of inflammatory diseases. This review encompasses the major discoveries in the field of LRRK2 pathobiology, from the initial gene cloning to the latest progress in LRRK2 inhibition as a promising therapeutic approach to fight neurodegeneration.
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Phytochemicals as Regulators of Genes Involved in Synucleinopathies. Biomolecules 2021; 11:biom11050624. [PMID: 33922207 PMCID: PMC8145209 DOI: 10.3390/biom11050624] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 04/13/2021] [Accepted: 04/14/2021] [Indexed: 12/13/2022] Open
Abstract
Synucleinopathies are a group of neurodegenerative diseases characterized by the accumulation of α-synuclein aggregates in neurons, nerve fibers or glial cells. Three main types of diseases belong to the synucleinopathies: Parkinson’s disease, dementia with Lewy bodies, and multiple system atrophy. All of them develop as a result of an interplay of genetic and environmental factors. Emerging evidence suggests that epigenetic mechanisms play an essential role in the development of synucleinopathies. Since there is no disease-modifying treatment for these disorders at this time, interest is growing in plant-derived chemicals as a potential treatment option. Phytochemicals are substances of plant origin that possess biological activity, which might have effects on human health. Phytochemicals with neuroprotective activity target different elements in pathogenic pathways due to their antioxidants, anti-inflammatory, and antiapoptotic properties, and ability to reduce cellular stress. Multiple recent studies demonstrate that the beneficial effects of phytochemicals may be explained by their ability to modulate the expression of genes implicated in synucleinopathies and other diseases. These substances may regulate transcription directly via transcription factors (TFs) or play the role of epigenetic regulators through their effect on histone modification, DNA methylation, and RNA-based mechanisms. Here, we summarize new data about the impact of phytochemicals on the pathogenesis of synucleinopathies through regulation of gene expression.
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LRRK2 at the Crossroad of Aging and Parkinson's Disease. Genes (Basel) 2021; 12:genes12040505. [PMID: 33805527 PMCID: PMC8066012 DOI: 10.3390/genes12040505] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Revised: 03/24/2021] [Accepted: 03/26/2021] [Indexed: 01/01/2023] Open
Abstract
Parkinson's disease (PD) is a heterogeneous neurodegenerative disease characterized by the progressive loss of dopaminergic neurons in the substantia nigra pars compacta and the widespread occurrence of proteinaceous inclusions known as Lewy bodies and Lewy neurites. The etiology of PD is still far from clear, but aging has been considered as the highest risk factor influencing the clinical presentations and the progression of PD. Accumulating evidence suggests that aging and PD induce common changes in multiple cellular functions, including redox imbalance, mitochondria dysfunction, and impaired proteostasis. Age-dependent deteriorations in cellular dysfunction may predispose individuals to PD, and cellular damages caused by genetic and/or environmental risk factors of PD may be exaggerated by aging. Mutations in the LRRK2 gene cause late-onset, autosomal dominant PD and comprise the most common genetic causes of both familial and sporadic PD. LRRK2-linked PD patients show clinical and pathological features indistinguishable from idiopathic PD patients. Here, we review cellular dysfunctions shared by aging and PD-associated LRRK2 mutations and discuss how the interplay between the two might play a role in PD pathologies.
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Brás IC, Outeiro TF. Alpha-Synuclein: Mechanisms of Release and Pathology Progression in Synucleinopathies. Cells 2021; 10:cells10020375. [PMID: 33673034 PMCID: PMC7917664 DOI: 10.3390/cells10020375] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Revised: 02/09/2021] [Accepted: 02/09/2021] [Indexed: 12/11/2022] Open
Abstract
The accumulation of misfolded alpha-synuclein (aSyn) throughout the brain, as Lewy pathology, is a phenomenon central to Parkinson’s disease (PD) pathogenesis. The stereotypical distribution and evolution of the pathology during disease is often attributed to the cell-to-cell transmission of aSyn between interconnected brain regions. The spreading of conformationally distinct aSyn protein assemblies, commonly referred as strains, is thought to result in a variety of clinically and pathologically heterogenous diseases known as synucleinopathies. Although tremendous progress has been made in the field, the mechanisms involved in the transfer of these assemblies between interconnected neural networks and their role in driving PD progression are still unclear. Here, we present an update of the relevant discoveries supporting or challenging the prion-like spreading hypothesis. We also discuss the importance of aSyn strains in pathology progression and the various putative molecular mechanisms involved in cell-to-cell protein release. Understanding the pathways underlying aSyn propagation will contribute to determining the etiology of PD and related synucleinopathies but also assist in the development of new therapeutic strategies.
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Affiliation(s)
- Inês C. Brás
- Center for Biostructural Imaging of Neurodegeneration, Department of Experimental Neurodegeneration, University Medical Center Göttingen, 37075 Göttingen, Germany;
| | - Tiago F. Outeiro
- Center for Biostructural Imaging of Neurodegeneration, Department of Experimental Neurodegeneration, University Medical Center Göttingen, 37075 Göttingen, Germany;
- Max Planck Institute for Experimental Medicine, 37075 Göttingen, Germany
- Faculty of Medical Sciences, Translational and Clinical Research Institute, Newcastle University, Framlington Place, Newcastle Upon Tyne NE2 4HH, UK
- Scientific Employee with a Honorary Contract at Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE), 37075 Göttingen, Germany
- Correspondence: ; Tel.: +49-(0)-551-391-3544; Fax: +49-(0)-551-392-2693
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Okechukwu C. Deciphering and manipulating the epigenome for the treatment of Parkinson’s and Alzheimer’s disease. MGM JOURNAL OF MEDICAL SCIENCES 2021. [DOI: 10.4103/mgmj.mgmj_90_20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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