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Belur NR, Bustos BI, Lubbe SJ, Mazzulli JR. Nuclear aggregates of NONO/SFPQ and A-to-I-edited RNA in Parkinson's disease and dementia with Lewy bodies. Neuron 2024; 112:2558-2580.e13. [PMID: 38761794 PMCID: PMC11309915 DOI: 10.1016/j.neuron.2024.05.003] [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: 05/27/2023] [Revised: 03/06/2024] [Accepted: 05/01/2024] [Indexed: 05/20/2024]
Abstract
Neurodegenerative diseases are commonly classified as proteinopathies that are defined by the aggregation of a specific protein. Parkinson's disease (PD) and dementia with Lewy bodies (DLB) are classified as synucleinopathies since α-synuclein (α-syn)-containing inclusions histopathologically define these diseases. Unbiased biochemical analysis of PD and DLB patient material unexpectedly revealed novel pathological inclusions in the nucleus comprising adenosine-to-inosine (A-to-I)-edited mRNAs and NONO and SFPQ proteins. These inclusions showed no colocalization with Lewy bodies and accumulated at levels comparable to α-syn. NONO and SFPQ aggregates reduced the expression of the editing inhibitor ADAR3, increasing A-to-I editing mainly within human-specific, Alu-repeat regions of axon, synaptic, and mitochondrial transcripts. Inosine-containing transcripts aberrantly accumulated in the nucleus, bound tighter to recombinant purified SFPQ in vitro, and potentiated SFPQ aggregation in human dopamine neurons, resulting in a self-propagating pathological state. Our data offer new insight into the inclusion composition and pathophysiology of PD and DLB.
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Affiliation(s)
- Nandkishore R Belur
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Bernabe I Bustos
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Steven J Lubbe
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA; Simpson Querrey Center for Neurogenetics, Northwestern University, Feinberg School of Medicine, Chicago, IL, USA
| | - Joseph R Mazzulli
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA.
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2
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Lee E, Park H, Kim S. Transcellular transmission and molecular heterogeneity of aggregation-prone proteins in neurodegenerative diseases. Mol Cells 2024; 47:100089. [PMID: 38971320 PMCID: PMC11286998 DOI: 10.1016/j.mocell.2024.100089] [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: 05/14/2024] [Revised: 06/26/2024] [Accepted: 07/01/2024] [Indexed: 07/08/2024] Open
Abstract
The accumulation of aggregation-prone proteins in a specific neuronal population is a common feature of neurodegenerative diseases, which is correlated with the development of pathological lesions in diseased brains. The formation and progression of pathological protein aggregates in susceptible neurons induce cellular dysfunction, resulting in progressive degeneration. Moreover, recent evidence supports the notion that the cell-to-cell transmission of pathological protein aggregates may be involved in the onset and progression of many neurodegenerative diseases. Indeed, several studies have identified different pathological aggregate strains. Although how these different aggregate strains form remains unclear, a variety of biomolecular compositions or cross-seeding events promoted by the presence of other protein aggregates in the cellular environment may affect the formation of different strains of pathological aggregates, which in turn can influence complex pathologies in diseased brains. In this review, we summarize the recent results regarding cell-to-cell transmission and the molecular heterogeneity of pathological aggregate strains, raising key questions for future research directions.
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Affiliation(s)
- Eunmin Lee
- Department of Biological Sciences and Biotechnology, Chungbuk National University, Cheongju, Chungbuk 28644, Korea
| | - Hyeonwoo Park
- Department of Biological Sciences and Biotechnology, Chungbuk National University, Cheongju, Chungbuk 28644, Korea
| | - Sangjune Kim
- Department of Biological Sciences and Biotechnology, Chungbuk National University, Cheongju, Chungbuk 28644, Korea.
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Wani WY, Zunke F, Belur NR, Mazzulli JR. The hexosamine biosynthetic pathway rescues lysosomal dysfunction in Parkinson's disease patient iPSC derived midbrain neurons. Nat Commun 2024; 15:5206. [PMID: 38897986 PMCID: PMC11186828 DOI: 10.1038/s41467-024-49256-3] [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: 01/30/2023] [Accepted: 05/30/2024] [Indexed: 06/21/2024] Open
Abstract
Disrupted glucose metabolism and protein misfolding are key characteristics of age-related neurodegenerative disorders including Parkinson's disease, however their mechanistic linkage is largely unexplored. The hexosamine biosynthetic pathway utilizes glucose and uridine-5'-triphosphate to generate N-linked glycans required for protein folding in the endoplasmic reticulum. Here we find that Parkinson's patient midbrain cultures accumulate glucose and uridine-5'-triphosphate, while N-glycan synthesis rates are reduced. Impaired glucose flux occurred by selective reduction of the rate-limiting enzyme, GFPT2, through disrupted signaling between the unfolded protein response and the hexosamine pathway. Failure of the unfolded protein response and reduced N-glycosylation caused immature lysosomal hydrolases to misfold and accumulate, while accelerating glucose flux through the hexosamine pathway rescued hydrolase function and reduced pathological α-synuclein. Our data indicate that the hexosamine pathway integrates glucose metabolism with lysosomal activity, and its failure in Parkinson's disease occurs by uncoupling of the unfolded protein response-hexosamine pathway axis. These findings offer new methods to restore proteostasis by hexosamine pathway enhancement.
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Affiliation(s)
- Willayat Y Wani
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA
| | - Friederike Zunke
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Nandkishore R Belur
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA
| | - Joseph R Mazzulli
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA.
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Zalon AJ, Quiriconi DJ, Pitcairn C, Mazzulli JR. α-Synuclein: Multiple pathogenic roles in trafficking and proteostasis pathways in Parkinson's disease. Neuroscientist 2024:10738584241232963. [PMID: 38420922 PMCID: PMC11358363 DOI: 10.1177/10738584241232963] [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] [Indexed: 03/02/2024]
Abstract
Parkinson's disease (PD) is a common age-related neurodegenerative disorder characterized by the loss of dopaminergic neurons in the midbrain. A hallmark of both familial and sporadic PD is the presence of Lewy body inclusions composed mainly of aggregated α-synuclein (α-syn), a presynaptic protein encoded by the SNCA gene. The mechanisms driving the relationship between α-syn accumulation and neurodegeneration are not completely understood, although recent evidence indicates that multiple branches of the proteostasis pathway are simultaneously perturbed when α-syn aberrantly accumulates within neurons. Studies from patient-derived midbrain cultures that develop α-syn pathology through the endogenous expression of PD-causing mutations show that proteostasis disruption occurs at the level of synthesis/folding in the endoplasmic reticulum (ER), downstream ER-Golgi trafficking, and autophagic-lysosomal clearance. Here, we review the fundamentals of protein transport, highlighting the specific steps where α-syn accumulation may intervene and the downstream effects on proteostasis. Current therapeutic efforts are focused on targeting single pathways or proteins, but the multifaceted pathogenic role of α-syn throughout the proteostasis pathway suggests that manipulating several targets simultaneously will provide more effective disease-modifying therapies for PD and other synucleinopathies.
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Affiliation(s)
- Annie J Zalon
- The Ken and Ruth Davee Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Drew J Quiriconi
- The Ken and Ruth Davee Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Caleb Pitcairn
- The Ken and Ruth Davee Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Joseph R Mazzulli
- The Ken and Ruth Davee Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
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5
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Szenci G, Glatz G, Takáts S, Juhász G. The Ykt6-Snap29-Syx13 SNARE complex promotes crinophagy via secretory granule fusion with Lamp1 carrier vesicles. Sci Rep 2024; 14:3200. [PMID: 38331993 PMCID: PMC10853563 DOI: 10.1038/s41598-024-53607-x] [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: 12/14/2023] [Accepted: 02/02/2024] [Indexed: 02/10/2024] Open
Abstract
In the Drosophila larval salivary gland, developmentally programmed fusions between lysosomes and secretory granules (SGs) and their subsequent acidification promote the maturation of SGs that are secreted shortly before puparium formation. Subsequently, ongoing fusions between non-secreted SGs and lysosomes give rise to degradative crinosomes, where the superfluous secretory material is degraded. Lysosomal fusions control both the quality and quantity of SGs, however, its molecular mechanism is incompletely characterized. Here we identify the R-SNARE Ykt6 as a novel regulator of crinosome formation, but not the acidification of maturing SGs. We show that Ykt6 localizes to Lamp1+ carrier vesicles, and forms a SNARE complex with Syntaxin 13 and Snap29 to mediate fusion with SGs. These Lamp1 carriers represent a distinct vesicle population that are functionally different from canonical Arl8+, Cathepsin L+ lysosomes, which also fuse with maturing SGs but are controlled by another SNARE complex composed of Syntaxin 13, Snap29 and Vamp7. Ykt6- and Vamp7-mediated vesicle fusions also determine the fate of SGs, as loss of either of these SNAREs prevents crinosomes from acquiring endosomal PI3P. Our results highlight that fusion events between SGs and different lysosome-related vesicle populations are critical for fine regulation of the maturation and crinophagic degradation of SGs.
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Affiliation(s)
- Győző Szenci
- Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest, 1117, Hungary
- Doctoral School of Biology, Institute of Biology, Eötvös Loránd University, Budapest, 1117, Hungary
| | - Gábor Glatz
- Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest, 1117, Hungary
| | - Szabolcs Takáts
- Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest, 1117, Hungary.
| | - Gábor Juhász
- Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest, 1117, Hungary.
- Institute of Genetics, HUN-REN Biological Research Centre Szeged, Szeged, 6726, Hungary.
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Palamarchuk IS, Slavich GM, Vaillancourt T, Rajji TK. Stress-related cellular pathophysiology as a crosstalk risk factor for neurocognitive and psychiatric disorders. BMC Neurosci 2023; 24:65. [PMID: 38087196 PMCID: PMC10714507 DOI: 10.1186/s12868-023-00831-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Accepted: 10/24/2023] [Indexed: 12/18/2023] Open
Abstract
In this narrative review, we examine biological processes linking psychological stress and cognition, with a focus on how psychological stress can activate multiple neurobiological mechanisms that drive cognitive decline and behavioral change. First, we describe the general neurobiology of the stress response to define neurocognitive stress reactivity. Second, we review aspects of epigenetic regulation, synaptic transmission, sex hormones, photoperiodic plasticity, and psychoneuroimmunological processes that can contribute to cognitive decline and neuropsychiatric conditions. Third, we explain mechanistic processes linking the stress response and neuropathology. Fourth, we discuss molecular nuances such as an interplay between kinases and proteins, as well as differential role of sex hormones, that can increase vulnerability to cognitive and emotional dysregulation following stress. Finally, we explicate several testable hypotheses for stress, neurocognitive, and neuropsychiatric research. Together, this work highlights how stress processes alter neurophysiology on multiple levels to increase individuals' risk for neurocognitive and psychiatric disorders, and points toward novel therapeutic targets for mitigating these effects. The resulting models can thus advance dementia and mental health research, and translational neuroscience, with an eye toward clinical application in cognitive and behavioral neurology, and psychiatry.
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Affiliation(s)
- Iryna S Palamarchuk
- Centre for Addiction and Mental Health, 1001 Queen Street West, Toronto, ON, M6J1H4, Canada.
- Department of Psychiatry, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada.
- Sunnybrook Health Sciences Centre, Division of Neurology, Toronto, ON, Canada.
- Temerty Faculty of Medicine, Toronto Dementia Research Alliance, University of Toronto, Toronto, ON, Canada.
| | - George M Slavich
- Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, Los Angeles, CA, USA
| | - Tracy Vaillancourt
- Counselling Psychology, Faculty of Education, University of Ottawa, Ottawa, ON, Canada
- School of Psychology, Faculty of Social Sciences, University of Ottawa, Ottawa, ON, Canada
| | - Tarek K Rajji
- Centre for Addiction and Mental Health, 1001 Queen Street West, Toronto, ON, M6J1H4, Canada
- Department of Psychiatry, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
- Temerty Faculty of Medicine, Toronto Dementia Research Alliance, University of Toronto, Toronto, ON, Canada
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Yin L, Xu Y, Yin J, Cheng H, Xiao W, Wu Y, Ji D, Gao S. Construction and validation of a risk model based on the key SNARE proteins to predict the prognosis and immune microenvironment of gliomas. Front Mol Neurosci 2023; 16:1304224. [PMID: 38115820 PMCID: PMC10728289 DOI: 10.3389/fnmol.2023.1304224] [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: 09/29/2023] [Accepted: 11/08/2023] [Indexed: 12/21/2023] Open
Abstract
Background Synaptic transmission between neurons and glioma cells can promote glioma progression. The soluble N-ethylmaleimide-sensitive fusion factor attachment protein receptors (SNARE) play a key role in synaptic functions. We aimed to construct and validate a novel model based on the SNARE proteins to predict the prognosis and immune microenvironment of glioma. Methods Differential expression analysis and COX regression analysis were used to identify key SRGs in glioma datasets, and we constructed a prognostic risk model based on the key SRGs. The prognostic value and predictive performance of the model were assessed in The Cancer Genome Atlas (TCGA) and Chinese glioma Genome Atlas (CGGA) datasets. Functional enrichment analysis and immune-related evaluation were employed to reveal the association of risk scores with tumor progression and microenvironment. A prognostic nomogram containing the risk score was established and assessed by calibration curves and time-dependent receiver operating characteristic curves. We verified the changes of the key SRGs in glioma specimens and cells by real-time quantitative PCR and Western blot analyses. Results Vesicle-associated membrane protein 2 (VAMP2) and vesicle-associated membrane protein 5 (VAMP5) were identified as two SRGs affecting the prognoses of glioma patients. High-risk patients characterized by higher VAMP5 and lower VAMP2 expression had a worse prognosis. Higher risk scores were associated with older age, higher tumor grades, IDH wild-type, and 1p19q non-codeletion. The SRGs risk model showed an excellent predictive performance in predicting the prognosis in TCGA and CGGA datasets. Differentially expressed genes between low- and high-risk groups were mainly enriched in the pathways related to immune infiltration, tumor metastasis, and neuronal activity. Immune score, stromal score, estimate score, tumor mutational burden, and expression of checkpoint genes were positively correlated with risk scores. The nomogram containing the risk score showed good performance in predicting the prognosis of glioma. Low VAMP2 and high VAMP5 were found in different grades of glioma specimens and cell lines. Conclusion We constructed and validated a novel risk model based on the expression of VAMP2 and VAMP5 by bioinformatics analysis and experimental confirmation. This model might be helpful for clinically predicting the prognosis and response to immunotherapy of glioma patients.
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Affiliation(s)
- Luxin Yin
- Department of Neurosurgery, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
- Institute of Nervous System Diseases, Xuzhou Medical University, Xuzhou, China
| | - Yiqiang Xu
- Department of Neurosurgery, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
- Institute of Nervous System Diseases, Xuzhou Medical University, Xuzhou, China
| | - Jiale Yin
- Institute of Nervous System Diseases, Xuzhou Medical University, Xuzhou, China
| | - Hai Cheng
- Department of Neurosurgery, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| | - Weihan Xiao
- Department of Neurosurgery, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| | - Yue Wu
- Institute of Nervous System Diseases, Xuzhou Medical University, Xuzhou, China
- Department of Neurosurgery, The Second Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| | - Daofei Ji
- Institute of Nervous System Diseases, Xuzhou Medical University, Xuzhou, China
- Department of Neurosurgery, The Second Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| | - Shangfeng Gao
- Department of Neurosurgery, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
- Institute of Nervous System Diseases, Xuzhou Medical University, Xuzhou, China
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Wang J, Joseph S, Vingill S, Dere E, Tatenhorst L, Ronnenberg A, Lingor P, Preisinger C, Ehrenreich H, Schulz JB, Stegmüller J. Loss of the parkinsonism-associated protein FBXO7 in glutamatergic forebrain neurons in mice leads to abnormal motor behavior and synaptic defects. J Neurochem 2023; 167:296-317. [PMID: 37753846 DOI: 10.1111/jnc.15962] [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: 02/23/2023] [Revised: 08/29/2023] [Accepted: 08/30/2023] [Indexed: 09/28/2023]
Abstract
Mutations in PARK15, which encodes for the F-box protein FBXO7 have been associated with Parkinsonian Pyramidal syndrome, a rare and complex movement disorder with Parkinsonian symptoms, pyramidal tract signs and juvenile onset. Our previous study showed that systemic loss of Fbxo7 in mice causes motor defects and premature death. We have also demonstrated that FBXO7 has a crucial role in neurons as the specific deletion in tyrosine hydroxylase-positive or glutamatergic forebrain neurons leads to late-onset or early-onset motor dysfunction, respectively. In this study, we examined NEX-Cre;Fbxo7fl/fl mice, in which Fbxo7 was specifically deleted in glutamatergic projection neurons. The effects of FBXO7 deficiency on striatal integrity were investigated with HPLC and histological analyses. NEX-Cre;Fbxo7fl/fl mice revealed an increase in striatal dopamine concentrations, changes in the glutamatergic, GABAergic and dopaminergic pathways, astrogliosis and microgliosis and little or no neuronal loss in the striatum. To determine the effects on the integrity of the synapse, we purified synaptic membranes, subjected them to quantitative mass spectrometry analysis and found alterations in the complement system, endocytosis and exocytosis pathways. These neuropathological changes coincide with alterations in spontaneous home cage behavior. Taken together, our findings suggest that FBXO7 is crucial for corticostriatal projections and the synaptic integrity of the striatum, and consequently for proper motor control.
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Affiliation(s)
- Jingbo Wang
- Department of Neurology, RWTH University Hospital, Aachen, Germany
| | - Sabitha Joseph
- Department of Neurology, RWTH University Hospital, Aachen, Germany
| | - Siv Vingill
- Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Ekrem Dere
- Sorbonne Université. Institut de Biologie Paris-Seine, (IBPS), Département UMR 8256, UFR des Sciences de la Vie, Campus Pierre et Marie Curie, Paris Cedex, France
- Clinical Neuroscience, Hermann Rein Strasse 3, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Lars Tatenhorst
- Department of Neurology, University Medical Center, Göttingen, Germany
| | - Anja Ronnenberg
- Clinical Neuroscience, Hermann Rein Strasse 3, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Paul Lingor
- Department of Neurology, School of Medicine, Klinikum rechts der Isar der Technischen Universität München, Munich, Germany
| | | | - Hannelore Ehrenreich
- Clinical Neuroscience, Hermann Rein Strasse 3, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Jörg B Schulz
- Department of Neurology, RWTH University Hospital, Aachen, Germany
- Jülich Aachen Research Alliance (JARA)-BRAIN Institute of Molecular Neuroscience and Neuroimaging, Research Center Jülich and RWTH Aachen University, Aachen, Germany
- Research Training Group 2416 MultiSenses-MultiScales, RWTH Aachen University, Aachen, Germany
| | - Judith Stegmüller
- Department of Neurology, RWTH University Hospital, Aachen, Germany
- Research Training Group 2416 MultiSenses-MultiScales, RWTH Aachen University, Aachen, Germany
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Fagen SJ, Burgess JD, Lim MJ, Amerna D, Kaya ZB, Faroqi AH, Perisetla P, DeMeo NN, Stojkovska I, Quiriconi DJ, Mazzulli JR, Delenclos M, Boschen SL, McLean PJ. Honokiol decreases alpha-synuclein mRNA levels and reveals novel targets for modulating alpha-synuclein expression. Front Aging Neurosci 2023; 15:1179086. [PMID: 37637959 PMCID: PMC10449643 DOI: 10.3389/fnagi.2023.1179086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 07/17/2023] [Indexed: 08/29/2023] Open
Abstract
Background Intracytoplasmic inclusions comprised of aggregated alpha-synuclein (αsyn) represent a key histopathological feature of neurological disorders collectively termed "synucleinopathies," which includes Parkinson's disease (PD). Mutations and multiplications in the SNCA gene encoding αsyn cause familial forms of PD and a large body of evidence indicate a correlation between αsyn accumulation and disease. Decreasing αsyn expression is recognized as a valid target for PD therapeutics, with down-regulation of SNCA expression potentially attenuating downstream cascades of pathologic events. Here, we evaluated if Honokiol (HKL), a polyphenolic compound derived from magnolia tree bark with demonstrated neuroprotective properties, can modulate αsyn levels in multiple experimental models. Methods Human neuroglioma cells stably overexpressing αsyn, mouse primary neurons, and human iPSC-derived neurons were exposed to HKL and αsyn protein and SNCA messenger RNA levels were assessed. The effect of HKL on rotenone-induced overexpression of αsyn levels was further assessed and transcriptional profiling of mouse cortical neurons treated with HKL was performed to identify potential targets of HKL. Results We demonstrate that HKL can successfully reduce αsyn protein levels and SNCA expression in multiple in vitro models of PD with our data supporting a mechanism whereby HKL acts by post-transcriptional modulation of SNCA rather than modulating αsyn protein degradation. Transcriptional profiling of mouse cortical neurons treated with HKL identifies several differentially expressed genes (DEG) as potential targets to modulate SNCA expression. Conclusion This study supports a HKL-mediated downregulation of SNCA as a viable strategy to modify disease progression in PD and other synucleinopathies. HKL has potential as a powerful tool for investigating SNCA gene modulation and its downstream effects.
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Affiliation(s)
- Sara J. Fagen
- Department of Neuroscience, Mayo Clinic, Jackson ville, FL, United States
| | - Jeremy D. Burgess
- Department of Neuroscience, Mayo Clinic, Jackson ville, FL, United States
- Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic College of Medicine, Rochester, MN, United States
| | - Melina J. Lim
- Department of Neuroscience, Mayo Clinic, Jackson ville, FL, United States
| | - Danilyn Amerna
- Department of Neuroscience, Mayo Clinic, Jackson ville, FL, United States
| | - Zeynep B. Kaya
- Department of Neuroscience, Mayo Clinic, Jackson ville, FL, United States
| | - Ayman H. Faroqi
- Department of Neuroscience, Mayo Clinic, Jackson ville, FL, United States
- Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic College of Medicine, Rochester, MN, United States
| | - Priyanka Perisetla
- Department of Neuroscience, Mayo Clinic, Jackson ville, FL, United States
| | - Natasha N. DeMeo
- Department of Neuroscience, Mayo Clinic, Jackson ville, FL, United States
| | - Iva Stojkovska
- Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
| | - Drew J. Quiriconi
- Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
| | - Joseph R. Mazzulli
- Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
| | - Marion Delenclos
- Department of Neuroscience, Mayo Clinic, Jackson ville, FL, United States
| | - Suelen L. Boschen
- Department of Neuroscience, Mayo Clinic, Jackson ville, FL, United States
- Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic College of Medicine, Rochester, MN, United States
- Department of Neurosurgery, Mayo Clinic, Jacksonville, FL, United States
| | - Pamela J. McLean
- Department of Neuroscience, Mayo Clinic, Jackson ville, FL, United States
- Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic College of Medicine, Rochester, MN, United States
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Drobny A, Boros FA, Balta D, Prieto Huarcaya S, Caylioglu D, Qazi N, Vandrey J, Schneider Y, Dobert JP, Pitcairn C, Mazzulli JR, Zunke F. Reciprocal effects of alpha-synuclein aggregation and lysosomal homeostasis in synucleinopathy models. Transl Neurodegener 2023; 12:31. [PMID: 37312133 PMCID: PMC10262594 DOI: 10.1186/s40035-023-00363-z] [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: 01/03/2023] [Accepted: 05/16/2023] [Indexed: 06/15/2023] Open
Abstract
BACKGROUND Lysosomal dysfunction has been implicated in a number of neurodegenerative diseases such as Parkinson's disease (PD). Various molecular, clinical and genetic studies have highlighted a central role of lysosomal pathways and proteins in the pathogenesis of PD. Within PD pathology the synaptic protein alpha-synuclein (αSyn) converts from a soluble monomer to oligomeric structures and insoluble amyloid fibrils. The aim of this study was to unravel the effect of αSyn aggregates on lysosomal turnover, particularly focusing on lysosomal homeostasis and cathepsins. Since these enzymes have been shown to be directly involved in the lysosomal degradation of αSyn, impairment of their enzymatic capacity has extensive consequences. METHODS We used patient-derived induced pluripotent stem cells and a transgenic mouse model of PD to examine the effect of intracellular αSyn conformers on cell homeostasis and lysosomal function in dopaminergic (DA) neurons by biochemical analyses. RESULTS We found impaired lysosomal trafficking of cathepsins in patient-derived DA neurons and mouse models with αSyn aggregation, resulting in reduced proteolytic activity of cathepsins in the lysosome. Using a farnesyltransferase inhibitor, which boosts hydrolase transport via activation of the SNARE protein ykt6, we enhanced the maturation and proteolytic activity of cathepsins and thereby decreased αSyn protein levels. CONCLUSIONS Our findings demonstrate a strong interplay between αSyn aggregation pathways and function of lysosomal cathepsins. It appears that αSyn directly interferes with the enzymatic function of cathepsins, which might lead to a vicious cycle of impaired αSyn degradation. Lysosomal trafficking of cathepsin D (CTSD), CTSL and CTSB is disrupted when alpha-synuclein (αSyn) is aggregated. This results in a decreased proteolytic activity of cathepsins, which directly mediate αSyn clearance. Boosting the transport of the cathepsins to the lysosome increases their activity and thus contributes to efficient αSyn degradation.
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Affiliation(s)
- Alice Drobny
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Fanni Annamária Boros
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Denise Balta
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Susy Prieto Huarcaya
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, 91054 Erlangen, Germany
- Institute of Biochemistry, Christian-Albrechts-University Kiel, Kiel, Germany
| | - Deniz Caylioglu
- Institute of Biochemistry, Christian-Albrechts-University Kiel, Kiel, Germany
| | - Niyeti Qazi
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Julia Vandrey
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Yanni Schneider
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Jan Philipp Dobert
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Caleb Pitcairn
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611 USA
| | - Joseph Robert Mazzulli
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611 USA
| | - Friederike Zunke
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, 91054 Erlangen, Germany
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11
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Gajendran N, Rajasekaran S, Witt SN. Knocking out alpha-synuclein in melanoma cells downregulates L1CAM and decreases motility. Sci Rep 2023; 13:9243. [PMID: 37286800 DOI: 10.1038/s41598-023-36451-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Accepted: 06/03/2023] [Indexed: 06/09/2023] Open
Abstract
The Parkinson's disease (PD) associated protein, alpha-synuclein (α-syn/SNCA), is highly expressed in aggressive melanomas. The goal of this study was to reveal possible mechanism(s) of α-syn involvement in melanoma pathogenesis. Herein, we asked whether α-syn modulates the expression of the pro-oncogenic adhesion molecules L1CAM and N-cadherin. We used two human melanoma cell lines (SK-MEL-28, SK-MEL-29), SNCA-knockout (KO) clones, and two human SH-SY5Y neuroblastoma cell lines. In the melanoma lines, loss of α-syn expression resulted in significant decreases in the expression of L1CAM and N-cadherin and concomitant significant decreases in motility. On average, there was a 75% reduction in motility in the four SNCA-KOs tested compared to control cells. Strikingly, comparing neuroblastoma SH-SY5Y cells that have no detectable α-syn to SH-SY5Y cells that stably express α-syn (SH/+αS), we found that expressing α-syn increased L1CAM and single-cell motility by 54% and 597%, respectively. The reduction in L1CAM level in SNCA-KO clones was not due to a transcriptional effect, rather we found that L1CAM is more efficiently degraded in the lysosome in SNCA-KO clones than in control cells. We propose that α-syn is pro-survival to melanoma (and possibly neuroblastoma) because it promotes the intracellular trafficking of L1CAM to the plasma membrane.
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Affiliation(s)
- Nithya Gajendran
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, USA
| | - Santhanasabapathy Rajasekaran
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, USA
| | - Stephan N Witt
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, USA.
- Feist-Weiller Cancer Center, Louisiana State University Health Shreveport, Shreveport, USA.
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12
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Jung D, Bachmann HS. Regulation of protein prenylation. Biomed Pharmacother 2023; 164:114915. [PMID: 37236024 DOI: 10.1016/j.biopha.2023.114915] [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: 03/27/2023] [Revised: 05/17/2023] [Accepted: 05/18/2023] [Indexed: 05/28/2023] Open
Abstract
Prenyltransferases (PTases) are known to play a role in embryonic development, normal tissue homeostasis and cancer by posttranslationally modifying proteins involved in these processes. They are being discussed as potential drug targets in an increasing number of diseases, ranging from Alzheimer's disease to malaria. Protein prenylation and the development of specific PTase inhibitors (PTIs) have been subject to intense research in recent decades. Recently, the FDA approved lonafarnib, a specific farnesyltransferase inhibitor that acts directly on protein prenylation; and bempedoic acid, an ATP citrate lyase inhibitor that might alter intracellular isoprenoid composition, the relative concentrations of which can exert a decisive influence on protein prenylation. Both drugs represent the first approved agent in their respective substance class. Furthermore, an overwhelming number of processes and proteins that regulate protein prenylation have been identified over the years, many of which have been proposed as molecular targets for pharmacotherapy in their own right. However, certain aspects of protein prenylation, such as the regulation of PTase gene expression or the modulation of PTase activity by phosphorylation, have attracted less attention, despite their reported influence on tumor cell proliferation. Here, we want to summarize the advances regarding our understanding of the regulation of protein prenylation and the potential implications for drug development. Additionally, we want to suggest new lines of investigation that encompass the search for regulatory elements for PTases, especially at the genetic and epigenetic levels.
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Affiliation(s)
- Dominik Jung
- Institute of Pharmacology and Toxicology, Center for Biomedical Education and Research (ZBAF), School of Medicine, Faculty of Health, Witten/Herdecke University, Witten, Germany
| | - Hagen S Bachmann
- Institute of Pharmacology and Toxicology, Center for Biomedical Education and Research (ZBAF), School of Medicine, Faculty of Health, Witten/Herdecke University, Witten, Germany.
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13
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Pitcairn C, Murata N, Zalon AJ, Stojkovska I, Mazzulli JR. Impaired Autophagic-Lysosomal Fusion in Parkinson's Patient Midbrain Neurons Occurs through Loss of ykt6 and Is Rescued by Farnesyltransferase Inhibition. J Neurosci 2023; 43:2615-2629. [PMID: 36788031 PMCID: PMC10082462 DOI: 10.1523/jneurosci.0610-22.2023] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 01/19/2023] [Accepted: 01/26/2023] [Indexed: 02/16/2023] Open
Abstract
Macroautophagy is a catabolic process that coordinates with lysosomes to degrade aggregation-prone proteins and damaged organelles. Loss of macroautophagy preferentially affects neuron viability and is associated with age-related neurodegeneration. We previously found that α-synuclein (α-syn) inhibits lysosomal function by blocking ykt6, a farnesyl-regulated soluble NSF attachment protein receptor (SNARE) protein that is essential for hydrolase trafficking in midbrain neurons. Using Parkinson's disease (PD) patient iPSC-derived midbrain cultures, we find that chronic, endogenous accumulation of α-syn directly inhibits autophagosome-lysosome fusion by impairing ykt6-SNAP-29 complexes. In wild-type (WT) cultures, ykt6 depletion caused a near-complete block of autophagic flux, highlighting its critical role for autophagy in human iPSC-derived neurons. In PD, macroautophagy impairment was associated with increased farnesyltransferase (FTase) activity, and FTase inhibitors restored macroautophagic flux through promoting active forms of ykt6 in human cultures, and male and female mice. Our findings indicate that ykt6 mediates cellular clearance by coordinating autophagic-lysosomal fusion and hydrolase trafficking, and that macroautophagy impairment in PD can be rescued by FTase inhibitors.SIGNIFICANCE STATEMENT The pathogenic mechanisms that lead to the death of neurons in Parkinson's disease (PD) and Dementia with Lewy bodies (LBD) are currently unknown. Furthermore, disease modifying treatments for these diseases do not exist. Our study indicates that a cellular clearance pathway termed autophagy is impaired in patient-derived culture models of PD and in vivo We identified a novel druggable target, a soluble NSF attachment protein receptor (SNARE) protein called ykt6, that rescues autophagy in vitro and in vivo upon blocking its farnesylation. Our work suggests that farnesyltransferase (FTase) inhibitors may be useful therapies for PD and DLB through enhancing autophagic-lysosomal clearance of aggregated proteins.
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Affiliation(s)
- Caleb Pitcairn
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611
| | - Naomi Murata
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611
| | - Annie J Zalon
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611
| | - Iva Stojkovska
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611
| | - Joseph R Mazzulli
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611
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14
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Haque R, Maity D. Small molecule-based fluorescent probes for the detection of α-Synuclein aggregation states. Bioorg Med Chem Lett 2023; 86:129257. [PMID: 36966976 DOI: 10.1016/j.bmcl.2023.129257] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 03/21/2023] [Accepted: 03/22/2023] [Indexed: 03/30/2023]
Abstract
The formation of aggregates due to protein misfolding is encountered in various neurodegenerative diseases. α-Synuclein (α-Syn) aggregation is linked to Parkinson's disease (PD). It is one of the most prevalent neurodegenerative disorders after Alzheimer's disease. Aggregation of α-Syn is associated with Lewy body formation and degeneration of the dopaminergic neurons in the brain. These are the pathological hallmarks of PD progression. α-Syn aggregates in a multi-step process. The native unstructured α-Syn monomers combine to form oligomers, followed by amyloid fibrils, and finally Lewy bodies. Recent evidence suggests that α-Syn oligomerization and fibrils formation play major roles in PD development. α-Syn oligomeric species is the main contributor to neurotoxicity. Therefore, the detection of α-Syn oligomers and fibrils has drawn significant attention for potential diagnostic and therapeutic development. In this regard, the fluorescence strategy has become the most popular approach for following the protein aggregation process. Thioflavin T (ThT) is the most frequently used probe for monitoring amyloid kinetics. Unfortunately, it suffers from several significant drawbacks including the inability to detect neurotoxic oligomers. Researchers developed several small molecule-based advanced fluorescent probes compared to ThT for the detection/monitoring of α-Syn aggregates states. These are summarized here.
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15
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RNAseq Analysis of FABP4 Knockout Mouse Hippocampal Transcriptome Suggests a Role for WNT/β-Catenin in Preventing Obesity-Induced Cognitive Impairment. Int J Mol Sci 2023; 24:ijms24043381. [PMID: 36834799 PMCID: PMC9961923 DOI: 10.3390/ijms24043381] [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: 12/22/2022] [Revised: 02/02/2023] [Accepted: 02/06/2023] [Indexed: 02/10/2023] Open
Abstract
Microglial fatty-acid binding protein 4 (FABP4) is a regulator of neuroinflammation. We hypothesized that the link between lipid metabolism and inflammation indicates a role for FABP4 in regulating high fat diet (HFD)-induced cognitive decline. We have previously shown that obese FABP4 knockout mice exhibit decreased neuroinflammation and cognitive decline. FABP4 knockout and wild type mice were fed 60% HFD for 12 weeks starting at 15 weeks old. Hippocampal tissue was dissected and RNA-seq was performed to measure differentially expressed transcripts. Reactome molecular pathway analysis was utilized to examine differentially expressed pathways. Results showed that HFD-fed FABP4 knockout mice have a hippocampal transcriptome consistent with neuroprotection, including associations with decreased proinflammatory signaling, ER stress, apoptosis, and cognitive decline. This is accompanied by an increase in transcripts upregulating neurogenesis, synaptic plasticity, long-term potentiation, and spatial working memory. Pathway analysis revealed that mice lacking FABP4 had changes in metabolic function that support reduction in oxidative stress and inflammation, and improved energy homeostasis and cognitive function. Analysis suggested a role for WNT/β-Catenin signaling in the protection against insulin resistance, alleviating neuroinflammation and cognitive decline. Collectively, our work shows that FABP4 represents a potential target in alleviating HFD-induced neuroinflammation and cognitive decline and suggests a role for WNT/β-Catenin in this protection.
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16
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Mächtel R, Boros FA, Dobert JP, Arnold P, Zunke F. From Lysosomal Storage Disorders to Parkinson's Disease - Challenges and Opportunities. J Mol Biol 2022:167932. [PMID: 36572237 DOI: 10.1016/j.jmb.2022.167932] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 12/14/2022] [Accepted: 12/19/2022] [Indexed: 12/24/2022]
Abstract
Lysosomes are specialized organelles with an acidic pH that act as recycling hubs for intracellular and extracellular components. They harbour numerous different hydrolytic enzymes to degrade substrates like proteins, peptides, and glycolipids. Reduced catalytic activity of lysosomal enzymes can cause the accumulation of these substrates and loss of lysosomal integrity, resulting in lysosomal dysfunction and lysosomal storage disorders (LSDs). Post-mitotic cells, such as neurons, seem to be highly sensitive to damages induced by lysosomal dysfunction, thus LSDs often manifest with neurological symptoms. Interestingly, some LSDs and Parkinson's disease (PD) share common cellular pathomechanisms, suggesting convergence of aetiology of the two disease types. This is further underlined by genetic associations of several lysosomal genes involved in LSDs with PD. The increasing number of lysosome-associated genetic risk factors for PD makes it necessary to understand functions and interactions of lysosomal proteins/enzymes both in health and disease, thereby holding the potential to identify new therapeutic targets. In this review, we highlight genetic and mechanistic interactions between the complex lysosomal network, LSDs and PD, and elaborate on methodical challenges in lysosomal research.
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Affiliation(s)
- Rebecca Mächtel
- Department of Molecular Neurology, University Clinics Erlangen, Erlangen, Germany
| | | | - Jan Philipp Dobert
- Department of Molecular Neurology, University Clinics Erlangen, Erlangen, Germany
| | - Philipp Arnold
- Institute of Functional and Clinical Anatomy, Friedrich-Alexander-University Erlangen-Nürnberg (FAU), Erlangen, Germany.
| | - Friederike Zunke
- Department of Molecular Neurology, University Clinics Erlangen, Erlangen, Germany.
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17
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Raja WK, Neves E, Burke C, Jiang X, Xu P, Rhodes KJ, Khurana V, Scannevin RH, Chung CY. Patient-derived three-dimensional cortical neurospheres to model Parkinson's disease. PLoS One 2022; 17:e0277532. [PMID: 36454869 PMCID: PMC9714816 DOI: 10.1371/journal.pone.0277532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Accepted: 10/28/2022] [Indexed: 12/03/2022] Open
Abstract
There are currently no preventive or disease-modifying therapies for Parkinson's Disease (PD). Failures in clinical trials necessitate a re-evaluation of existing pre-clinical models in order to adopt systems that better recapitulate underlying disease mechanisms and better predict clinical outcomes. In recent years, models utilizing patient-derived induced pluripotent stem cells (iPSC) have emerged as attractive models to recapitulate disease-relevant neuropathology in vitro without exogenous overexpression of disease-related pathologic proteins. Here, we utilized iPSC derived from patients with early-onset PD and dementia phenotypes that harbored either a point mutation (A53T) or multiplication at the α-synuclein/SNCA gene locus. We generated a three-dimensional (3D) cortical neurosphere culture model to better mimic the tissue microenvironment of the brain. We extensively characterized the differentiation process using quantitative PCR, Western immunoblotting and immunofluorescence staining. Differentiated and aged neurospheres revealed alterations in fatty acid profiles and elevated total and pathogenic phospho-α-synuclein levels in both A53T and the triplication lines compared to their isogenic control lines. Furthermore, treatment of the neurospheres with a small molecule inhibitor of stearoyl CoA desaturase (SCD) attenuated the protein accumulation and aberrant fatty acid profile phenotypes. Our findings suggest that the 3D cortical neurosphere model is a useful tool to interrogate targets for PD and amenable to test small molecule therapeutics.
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Affiliation(s)
- Waseem K. Raja
- Yumanity Therapeutics, Boston, MA, United States of America
- * E-mail: (CYC); (WKR)
| | - Esther Neves
- Yumanity Therapeutics, Boston, MA, United States of America
| | | | - Xin Jiang
- Yumanity Therapeutics, Boston, MA, United States of America
| | - Ping Xu
- Yumanity Therapeutics, Boston, MA, United States of America
| | | | - Vikram Khurana
- Department of Neurology, Brigham and Women’s Hospital and Harvard Medical School, Ann Romney Center for Neurologic Disease, Boston, MA, United States of America
- Harvard Stem Cell Institute, Cambridge, MA, United States of America
- Broad Institute of MIT and Harvard, Cambridge, MA, United States of America
| | | | - Chee Yeun Chung
- Yumanity Therapeutics, Boston, MA, United States of America
- * E-mail: (CYC); (WKR)
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18
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Wang T, Zhou Y, Zheng H, Shen T, Wang D, Zhang J. Chemoproteomics identifies Ykt6 as the direct target of schisandrin A for neuroprotection. CHINESE CHEM LETT 2022. [DOI: 10.1016/j.cclet.2022.107887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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19
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Cuddy LK, Alia AO, Salvo MA, Chandra S, Grammatopoulos TN, Justman CJ, Lansbury PT, Mazzulli JR, Vassar R. Farnesyltransferase inhibitor LNK-754 attenuates axonal dystrophy and reduces amyloid pathology in mice. Mol Neurodegener 2022; 17:54. [PMID: 35987691 PMCID: PMC9392365 DOI: 10.1186/s13024-022-00561-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Accepted: 08/11/2022] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Amyloid plaque deposition and axonal degeneration are early events in AD pathogenesis. Aβ disrupts microtubules in presynaptic dystrophic neurites, resulting in the accumulation of impaired endolysosomal and autophagic organelles transporting β-site amyloid precursor protein cleaving enzyme (BACE1). Consequently, dystrophic neurites generate Aβ42 and significantly contribute to plaque deposition. Farnesyltransferase inhibitors (FTIs) have recently been investigated for repositioning toward the treatment of neurodegenerative disorders and block the action of farnesyltransferase (FTase) to catalyze farnesylation, a post-translational modification that regulates proteins involved in lysosome function and microtubule stability. In postmortem AD brains, FTase and its downstream signaling are upregulated. However, the impact of FTIs on amyloid pathology and dystrophic neurites is unknown. METHODS We tested the effects of the FTIs LNK-754 and lonafarnib in the 5XFAD mouse model of amyloid pathology. RESULTS In 2-month-old 5XFAD mice treated chronically for 3 months, LNK-754 reduced amyloid plaque burden, tau hyperphosphorylation, and attenuated the accumulation of BACE1 and LAMP1 in dystrophic neurites. In 5-month-old 5XFAD mice treated acutely for 3 weeks, LNK-754 reduced dystrophic neurite size and LysoTracker-Green accumulation in the absence of effects on Aβ deposits. Acute treatment with LNK-754 improved memory and learning deficits in hAPP/PS1 amyloid mice. In contrast to LNK-754, lonafarnib treatment was less effective at reducing plaques, tau hyperphosphorylation and dystrophic neurites, which could have resulted from reduced potency against FTase compared to LNK-754. We investigated the effects of FTIs on axonal trafficking of endolysosomal organelles and found that lonafarnib and LNK-754 enhanced retrograde axonal transport in primary neurons, indicating FTIs could support the maturation of axonal late endosomes into lysosomes. Furthermore, FTI treatment increased levels of LAMP1 in mouse primary neurons and in the brains of 5XFAD mice, demonstrating that FTIs stimulated the biogenesis of endolysosomal organelles. CONCLUSIONS We show new data to suggest that LNK-754 promoted the axonal trafficking and function of endolysosomal compartments, which we hypothesize decreased axonal dystrophy, reduced BACE1 accumulation and inhibited amyloid deposition in 5XFAD mice. Our results agree with previous work identifying FTase as a therapeutic target for treating proteinopathies and could have important therapeutic implications in treating AD.
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Affiliation(s)
- Leah K. Cuddy
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611 USA
| | - Alia O. Alia
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611 USA
| | - Miranda A. Salvo
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611 USA
| | - Sidhanth Chandra
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611 USA
| | | | | | - Peter T. Lansbury
- Bial Biotech, Cambridge, MA 02139 USA
- Department of Neurology, Harvard Medical School, Cambridge, MA 02139 USA
| | - Joseph R. Mazzulli
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611 USA
| | - Robert Vassar
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611 USA
- Mesulam Center for Cognitive Neurology and Alzheimer’s Disease, Northwestern University Feinberg School of Medicine, Chicago, IL 60611 USA
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20
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Drobny A, Prieto Huarcaya S, Dobert J, Kluge A, Bunk J, Schlothauer T, Zunke F. The role of lysosomal cathepsins in neurodegeneration: Mechanistic insights, diagnostic potential and therapeutic approaches. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2022; 1869:119243. [PMID: 35217144 DOI: 10.1016/j.bbamcr.2022.119243] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 02/08/2022] [Accepted: 02/10/2022] [Indexed: 12/12/2022]
Abstract
Lysosomes are ubiquitous organelles with a fundamental role in maintaining cellular homeostasis by mediating degradation and recycling processes. Cathepsins are the most abundant lysosomal hydrolyses and are responsible for the bulk degradation of various substrates. A correct autophagic function is essential for neuronal survival, as most neurons are post-mitotic and thus susceptible to accumulate cellular components. Increasing evidence suggests a crucial role of the lysosome in neurodegeneration as a key regulator of aggregation-prone and disease-associated proteins, such as α-synuclein, β-amyloid and huntingtin. Particularly, alterations in lysosomal cathepsins CTSD, CTSB and CTSL can contribute to the pathogenesis of neurodegenerative diseases as seen for neuronal ceroid lipofuscinosis, synucleinopathies (Parkinson's disease, Dementia with Lewy Body and Multiple System Atrophy) as well as Alzheimer's and Huntington's disease. In this review, we provide an overview of recent evidence implicating CTSD, CTSB and CTSL in neurodegeneration, with a special focus on the role of these enzymes in α-synuclein metabolism. In addition, we summarize the potential role of lysosomal cathepsins as clinical biomarkers in neurodegenerative diseases and discuss potential therapeutic approaches by targeting lysosomal function.
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Affiliation(s)
- Alice Drobny
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | | | - Jan Dobert
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Annika Kluge
- Department of Neurology, Christian-Albrechts-University Kiel, Kiel, Germany
| | - Josina Bunk
- Institute of Biochemistry, Christian-Albrechts-University Kiel, Kiel, Germany
| | | | - Friederike Zunke
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany.
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21
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Menon S, Armstrong S, Hamzeh A, Visanji NP, Sardi SP, Tandon A. Alpha-Synuclein Targeting Therapeutics for Parkinson's Disease and Related Synucleinopathies. Front Neurol 2022; 13:852003. [PMID: 35614915 PMCID: PMC9124903 DOI: 10.3389/fneur.2022.852003] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 04/01/2022] [Indexed: 12/14/2022] Open
Abstract
α-Synuclein (asyn) is a key pathogenetic factor in a group of neurodegenerative diseases generically known as synucleinopathies, including Parkinson's disease (PD), dementia with Lewy bodies (DLB) and multiple system atrophy (MSA). Although the initial triggers of pathology and progression are unclear, multiple lines of evidence support therapeutic targeting of asyn in order to limit its prion-like misfolding. Here, we review recent pre-clinical and clinical work that offers promising treatment strategies to sequester, degrade, or silence asyn expression as a means to reduce the levels of seed or substrate. These diverse approaches include removal of aggregated asyn with passive or active immunization or by expression of vectorized antibodies, modulating kinetics of misfolding with small molecule anti-aggregants, lowering asyn gene expression by antisense oligonucleotides or inhibitory RNA, and pharmacological activation of asyn degradation pathways. We also discuss recent technological advances in combining low intensity focused ultrasound with intravenous microbubbles to transiently increase blood-brain barrier permeability for improved brain delivery and target engagement of these large molecule anti-asyn biologics.
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Affiliation(s)
- Sindhu Menon
- Tanz Centre for Research in Neurodegenerative Diseases, Toronto, ON, Canada
| | - Sabrina Armstrong
- Tanz Centre for Research in Neurodegenerative Diseases, Toronto, ON, Canada
| | - Amir Hamzeh
- Tanz Centre for Research in Neurodegenerative Diseases, Toronto, ON, Canada
| | - Naomi P. Visanji
- Tanz Centre for Research in Neurodegenerative Diseases, Toronto, ON, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
- Krembil Research Institute, Toronto, ON, Canada
| | | | - Anurag Tandon
- Tanz Centre for Research in Neurodegenerative Diseases, Toronto, ON, Canada
- Department of Medicine, University of Toronto, Toronto, ON, Canada
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22
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Prieto Huarcaya S, Drobny A, Marques ARA, Di Spiezio A, Dobert JP, Balta D, Werner C, Rizo T, Gallwitz L, Bub S, Stojkovska I, Belur NR, Fogh J, Mazzulli JR, Xiang W, Fulzele A, Dejung M, Sauer M, Winner B, Rose-John S, Arnold P, Saftig P, Zunke F. Recombinant pro-CTSD (cathepsin D) enhances SNCA/α-Synuclein degradation in α-Synucleinopathy models. Autophagy 2022; 18:1127-1151. [PMID: 35287553 PMCID: PMC9196656 DOI: 10.1080/15548627.2022.2045534] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Parkinson disease (PD) is a neurodegenerative disorder characterized by the abnormal intracellular accumulation of SNCA/α-synuclein. While the exact mechanisms underlying SNCA pathology are not fully understood, increasing evidence suggests the involvement of autophagy as well as lysosomal deficiencies. Because CTSD (cathepsin D) has been proposed to be the major lysosomal protease involved in SNCA degradation, its deficiency has been linked to the presence of insoluble SNCA conformers in the brain of mice and humans as well as to the transcellular transmission of SNCA aggregates. We here postulate that SNCA degradation can be enhanced by the application of the recombinant human proform of CTSD (rHsCTSD). Our results reveal that rHsCTSD is efficiently endocytosed by neuronal cells, correctly targeted to lysosomes and matured to an enzymatically active protease. In dopaminergic neurons derived from induced pluripotent stem cells (iPSC) of PD patients harboring the A53T mutation within the SNCA gene, we confirm the reduction of insoluble SNCA after treatment with rHsCTSD. Moreover, we demonstrate a decrease of pathological SNCA conformers in the brain and within primary neurons of a ctsd-deficient mouse model after dosing with rHsCTSD. Boosting lysosomal CTSD activity not only enhanced SNCA clearance in human and murine neurons as well as tissue, but also restored endo-lysosome and autophagy function. Our findings indicate that CTSD is critical for SNCA clearance and function. Thus, enzyme replacement strategies utilizing CTSD may also be of therapeutic interest for the treatment of PD and other synucleinopathies aiming to decrease the SNCA burden.Abbreviations: aa: amino acid; SNCA/α-synuclein: synuclein alpha; APP: amyloid beta precursor protein; BBB: blood brain barrier; BF: basal forebrain; CBB: Coomassie Brilliant Blue; CLN: neuronal ceroid lipofuscinosis; CNL10: neuronal ceroid lipofuscinosis type 10; Corr.: corrected; CTSD: cathepsin D; CTSB: cathepsin B; DA: dopaminergic; DA-iPSn: induced pluripotent stem cell-derived dopaminergic neurons; dox: doxycycline; ERT: enzyme replacement therapy; Fx: fornix, GBA/β-glucocerebrosidase: glucosylceramidase beta; h: hour; HC: hippocampus; HT: hypothalamus; i.c.: intracranially; IF: immunofluorescence; iPSC: induced pluripotent stem cell; KO: knockout; LAMP1: lysosomal associated membrane protein 1; LSDs: lysosomal storage disorders; MAPT: microtubule associated protein tau; M6P: mannose-6-phosphate; M6PR: mannose-6-phosphate receptor; MB: midbrain; mCTSD: mature form of CTSD; neurofil.: neurofilament; PD: Parkinson disease; proCTSD: proform of CTSD; PRNP: prion protein; RFU: relative fluorescence units; rHsCTSD: recombinant human proCTSD; SAPC: Saposin C; SIM: structured illumination microscopy; T-insol: Triton-insoluble; T-sol: Triton-soluble; TEM: transmission electron microscopy, TH: tyrosine hydroxylase; Thal: thalamus.
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Affiliation(s)
| | - Alice Drobny
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg (Fau), Erlangen, Germany
| | - André R A Marques
- iNOVA4Health, Chronic Diseases Research Center (CEDOC), Nova Medical School, Nms, Nova University Lisbon, Lisboa, Portugal
| | | | - Jan Philipp Dobert
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg (Fau), Erlangen, Germany
| | - Denise Balta
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg (Fau), Erlangen, Germany
| | - Christian Werner
- Department of Biotechnology and Biophysics, University of Würzburg, Biocenter, Am Hubland, Würzburg, Germany
| | - Tania Rizo
- Department of Stem Cell Biology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Lisa Gallwitz
- Institute of Biochemistry, Christian-Albrechts-University Kiel, Kiel, Germany
| | - Simon Bub
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg (Fau), Erlangen, Germany
| | - Iva Stojkovska
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois USA
| | - Nandkishore R Belur
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois USA
| | | | - Joseph R Mazzulli
- Department of Biotechnology and Biophysics, University of Würzburg, Biocenter, Am Hubland, Würzburg, Germany
| | - Wei Xiang
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg (Fau), Erlangen, Germany
| | - Amitkumar Fulzele
- Institute of Molecular Biology (IMB), Ackermannweg 4, Mainz, Germany
| | - Mario Dejung
- Institute of Molecular Biology (IMB), Ackermannweg 4, Mainz, Germany
| | - Markus Sauer
- Department of Biotechnology and Biophysics, University of Würzburg, Biocenter, Am Hubland, Würzburg, Germany
| | - Beate Winner
- Department of Stem Cell Biology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Stefan Rose-John
- Institute of Biochemistry, Christian-Albrechts-University Kiel, Kiel, Germany
| | - Philipp Arnold
- Institute of Functional and Clinical Anatomy, Friedrich-Alexander-University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Paul Saftig
- Institute of Biochemistry, Christian-Albrechts-University Kiel, Kiel, Germany
| | - Friederike Zunke
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg (Fau), Erlangen, Germany
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23
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Gasparotto M, Lee YS, Palazzi A, Vacca M, Filippini F. Nuclear and Cytoplasmatic Players in Mitochondria-Related CNS Disorders: Chromatin Modifications and Subcellular Trafficking. Biomolecules 2022; 12:biom12050625. [PMID: 35625553 PMCID: PMC9138954 DOI: 10.3390/biom12050625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 04/19/2022] [Accepted: 04/22/2022] [Indexed: 12/10/2022] Open
Abstract
Aberrant mitochondrial phenotypes are common to many central nervous system (CNS) disorders, including neurodegenerative and neurodevelopmental diseases. Mitochondrial function and homeostasis depend on proper control of several biological processes such as chromatin remodeling and transcriptional control, post-transcriptional events, vesicle and organelle subcellular trafficking, fusion, and morphogenesis. Mutation or impaired regulation of major players that orchestrate such processes can disrupt cellular and mitochondrial dynamics, contributing to neurological disorders. The first part of this review provides an overview of a functional relationship between chromatin players and mitochondria. Specifically, we relied on specific monogenic CNS disorders which share features with mitochondrial diseases. On the other hand, subcellular trafficking is coordinated directly or indirectly through evolutionarily conserved domains and proteins that regulate the dynamics of membrane compartments and organelles, including mitochondria. Among these “building blocks”, longin domains and small GTPases are involved in autophagy and mitophagy, cell reshaping, and organelle fusion. Impairments in those processes significantly impact CNS as well and are discussed in the second part of the review. Hopefully, in filling the functional gap between the nucleus and cytoplasmic organelles new routes for therapy could be disclosed.
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Affiliation(s)
- Matteo Gasparotto
- Synthetic Biology and Biotechnology Unit, Department of Biology, University of Padua, Via Ugo Bassi 58/B, 35131 Padua, Italy;
| | - Yi-Shin Lee
- Institute of Genetics and Biophysics “A. Buzzati Traverso”, CNR, Via Pietro Castellino, 111, 80131 Naples, Italy; (Y.-S.L.); (A.P.); (M.V.)
- Pharmacology Division, Department of Neuroscience, Reproductive and Odontostomatological Sciences, Faculty of Medicine and surgery, University of Naples Federico II, Via Pansini 5, Building 19 (Biological Tower), 80131 Naples, Italy
| | - Alessandra Palazzi
- Institute of Genetics and Biophysics “A. Buzzati Traverso”, CNR, Via Pietro Castellino, 111, 80131 Naples, Italy; (Y.-S.L.); (A.P.); (M.V.)
| | - Marcella Vacca
- Institute of Genetics and Biophysics “A. Buzzati Traverso”, CNR, Via Pietro Castellino, 111, 80131 Naples, Italy; (Y.-S.L.); (A.P.); (M.V.)
| | - Francesco Filippini
- Synthetic Biology and Biotechnology Unit, Department of Biology, University of Padua, Via Ugo Bassi 58/B, 35131 Padua, Italy;
- Correspondence:
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24
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Sepúlveda D, Cisternas-Olmedo M, Arcos J, Nassif M, Vidal RL. Contribution of Autophagy-Lysosomal Pathway in the Exosomal Secretion of Alpha-Synuclein and Its Impact in the Progression of Parkinson’s Disease. Front Mol Neurosci 2022; 15:805087. [PMID: 35250476 PMCID: PMC8891570 DOI: 10.3389/fnmol.2022.805087] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 01/07/2022] [Indexed: 01/07/2023] Open
Abstract
Parkinson’s disease (PD) is caused by the degeneration of dopaminergic neurons due to an accumulation of intraneuronal abnormal alpha-synuclein (α-syn) protein aggregates. It has been reported that the levels of exosomal α-syn of neuronal origin in plasma correlate significantly with motor dysfunction, highlighting the exosomes containing α-syn as a potential biomarker of PD. In addition, it has been found that the selective autophagy-lysosomal pathway (ALP) contributes to the secretion of misfolded proteins involved in neurodegenerative diseases. In this review, we describe the evidence that supports the relationship between the ALP and α-syn exosomal secretion on the PD progression and its implications in the diagnosis and progression of this pathology.
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Affiliation(s)
- Denisse Sepúlveda
- Center for Integrative Biology, Facultad de Ciencias, Universidad Mayor, Santiago, Chile
- Biomedical Neuroscience Institute, University of Chile, Santiago, Chile
- Geroscience Center for Brain Health and Metabolism, Santiago, Chile
| | - Marisol Cisternas-Olmedo
- Center for Integrative Biology, Facultad de Ciencias, Universidad Mayor, Santiago, Chile
- Biomedical Neuroscience Institute, University of Chile, Santiago, Chile
- Geroscience Center for Brain Health and Metabolism, Santiago, Chile
| | - Javiera Arcos
- Center for Integrative Biology, Facultad de Ciencias, Universidad Mayor, Santiago, Chile
- Biomedical Neuroscience Institute, University of Chile, Santiago, Chile
- Geroscience Center for Brain Health and Metabolism, Santiago, Chile
| | - Melissa Nassif
- Center for Integrative Biology, Facultad de Ciencias, Universidad Mayor, Santiago, Chile
- Escuela de Biotecnología, Facultad de Ciencias, Universidad Mayor, Santiago, Chile
| | - René L. Vidal
- Center for Integrative Biology, Facultad de Ciencias, Universidad Mayor, Santiago, Chile
- Biomedical Neuroscience Institute, University of Chile, Santiago, Chile
- Geroscience Center for Brain Health and Metabolism, Santiago, Chile
- *Correspondence: René L. Vidal,
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25
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Abstract
How do protein aggregates contribute to neurodegenerative disorders, and can they be therapeutically targeted? In this issue of Neuron, Stojkovska et al. (2022) show that aggregated α-synuclein disrupts ER and lysosomal function in Parkinson's disease patient-derived neurons and that combined enhancement of multiple arms of the proteostasis network improves these defects.
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Affiliation(s)
- Christopher J Griffey
- Doctoral Program in Neurobiology and Behavior, Medical Scientist Training Program, Columbia University, New York, NY, USA
| | - Ai Yamamoto
- Departments of Neurology, and Pathology and Cell Biology, Columbia University, New York, NY, USA.
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26
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Stojkovska I, Wani WY, Zunke F, Belur NR, Pavlenko EA, Mwenda N, Sharma K, Francelle L, Mazzulli JR. Rescue of α-synuclein aggregation in Parkinson's patient neurons by synergistic enhancement of ER proteostasis and protein trafficking. Neuron 2022; 110:436-451.e11. [PMID: 34793693 PMCID: PMC8815333 DOI: 10.1016/j.neuron.2021.10.032] [Citation(s) in RCA: 39] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 07/19/2021] [Accepted: 10/21/2021] [Indexed: 02/04/2023]
Abstract
Neurodegenerative disorders are characterized by a collapse in proteostasis, as shown by the accumulation of insoluble protein aggregates in the brain. Proteostasis involves a balance of protein synthesis, folding, trafficking, and degradation, but how aggregates perturb these pathways is unknown. Using Parkinson's disease (PD) patient midbrain cultures, we find that aggregated α-synuclein induces endoplasmic reticulum (ER) fragmentation and compromises ER protein folding capacity, leading to misfolding and aggregation of immature lysosomal β-glucocerebrosidase. Despite this, PD neurons fail to initiate the unfolded protein response, indicating perturbations in sensing or transducing protein misfolding signals in the ER. Small molecule enhancement of ER proteostasis machinery promotes β-glucocerebrosidase solubility, while simultaneous enhancement of trafficking improves ER morphology, lysosomal function, and reduces α-synuclein. Our studies suggest that aggregated α-synuclein perturbs the ability of neurons to respond to misfolded proteins in the ER, and that synergistic enhancement of multiple proteostasis branches may provide therapeutic benefit in PD.
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Affiliation(s)
- Iva Stojkovska
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Willayat Y Wani
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Friederike Zunke
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA; Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Nandkishore R Belur
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Egor A Pavlenko
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Nkatha Mwenda
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Karan Sharma
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Laetitia Francelle
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Joseph R Mazzulli
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA.
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27
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Pang SYY, Lo RCN, Ho PWL, Liu HF, Chang EES, Leung CT, Malki Y, Choi ZYK, Wong WY, Kung MHW, Ramsden DB, Ho SL. LRRK2, GBA and their interaction in the regulation of autophagy: implications on therapeutics in Parkinson's disease. Transl Neurodegener 2022; 11:5. [PMID: 35101134 PMCID: PMC8805403 DOI: 10.1186/s40035-022-00281-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Accepted: 01/12/2022] [Indexed: 02/06/2023] Open
Abstract
Mutations in leucine-rich repeat kinase 2 (LRRK2) and glucocerebrosidase (GBA) represent two most common genetic causes of Parkinson’s disease (PD). Both genes are important in the autophagic-lysosomal pathway (ALP), defects of which are associated with α-synuclein (α-syn) accumulation. LRRK2 regulates macroautophagy via activation of the mitogen activated protein kinase/extracellular signal regulated protein kinase (MAPK/ERK) kinase (MEK) and the calcium-dependent adenosine monophosphate (AMP)-activated protein kinase (AMPK) pathways. Phosphorylation of Rab GTPases by LRRK2 regulates lysosomal homeostasis and endosomal trafficking. Mutant LRRK2 impairs chaperone-mediated autophagy, resulting in α-syn binding and oligomerization on lysosomal membranes. Mutations in GBA reduce glucocerebrosidase (GCase) activity, leading to glucosylceramide accumulation, α-syn aggregation and broad autophagic abnormalities. LRRK2 and GBA influence each other: GCase activity is reduced in LRRK2 mutant cells, and LRRK2 kinase inhibition can alter GCase activity in GBA mutant cells. Clinically, LRRK2 G2019S mutation seems to modify the effects of GBA mutation, resulting in milder symptoms than those resulting from GBA mutation alone. However, dual mutation carriers have an increased risk of PD and earlier age of onset compared with single mutation carriers, suggesting an additive deleterious effect on the initiation of PD pathogenic processes. Crosstalk between LRRK2 and GBA in PD exists, but its exact mechanism is unclear. Drugs that inhibit LRRK2 kinase or activate GCase are showing efficacy in pre-clinical models. Since LRRK2 kinase and GCase activities are also altered in idiopathic PD (iPD), it remains to be seen if these drugs will be useful in disease modification of iPD.
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28
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Glucocerebrosidase dysfunction in neurodegenerative disease. Essays Biochem 2021; 65:873-883. [PMID: 34528667 DOI: 10.1042/ebc20210018] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 08/26/2021] [Accepted: 09/01/2021] [Indexed: 12/12/2022]
Abstract
Parkinson's disease (PD) and related neurodegenerative disorders, termed the synucleinopathies, are characterized pathologically by the accumulation of protein aggregates containing α-synuclein (aSyn), resulting in progressive neuronal loss. There is considerable need for the development of neuroprotective strategies to halt or slow disease progression in these disorders. To this end, evaluation of genetic mutations associated with the synucleinopathies has helped to elucidate crucial mechanisms of disease pathogenesis, revealing key roles for lysosomal and mitochondrial dysfunction. The GBA1 gene, which encodes the lysosomal hydrolase β-glucocerebrosidase (GCase) is the most common genetic risk factor for PD and is also linked to other neurodegenerative disorders including dementia with Lewy bodies (DLB). Additionally, homozygous mutations in GBA1 are associated with the rare lysosomal storage disorder, Gaucher's disease (GD). In this review, we discuss the current knowledge in the field regarding the diverse roles of GCase in neurons and the multifactorial effects of loss of GCase enzymatic activity. Importantly, GCase has been shown to have a bidirectional relationship with aSyn, resulting in a pathogenic feedback loop that can lead to progressive aSyn accumulation. Alterations in GCase activity have furthermore been linked to multiple distinct pathways involved in neurodegeneration, and therefore GCase has emerged as a promising target for therapeutic drug development for PD and related neurodegenerative disorders, particularly DLB.
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29
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Fredriksen K, Aivazidis S, Sharma K, Burbidge KJ, Pitcairn C, Zunke F, Gelyana E, Mazzulli JR. Pathological α-syn aggregation is mediated by glycosphingolipid chain length and the physiological state of α-syn in vivo. Proc Natl Acad Sci U S A 2021; 118:e2108489118. [PMID: 34893541 PMCID: PMC8685670 DOI: 10.1073/pnas.2108489118] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/25/2021] [Indexed: 11/18/2022] Open
Abstract
GBA1 mutations that encode lysosomal β-glucocerebrosidase (GCase) cause the lysosomal storage disorder Gaucher disease (GD) and are strong risk factors for synucleinopathies, including Parkinson's disease and Lewy body dementia. Only a subset of subjects with GBA1 mutations exhibit neurodegeneration, and the factors that influence neurological phenotypes are unknown. We find that α-synuclein (α-syn) neuropathology induced by GCase depletion depends on neuronal maturity, the physiological state of α-syn, and specific accumulation of long-chain glycosphingolipid (GSL) GCase substrates. Reduced GCase activity does not initiate α-syn aggregation in neonatal mice or immature human midbrain cultures; however, adult mice or mature midbrain cultures that express physiological α-syn oligomers are aggregation prone. Accumulation of long-chain GSLs (≥C22), but not short-chain species, induced α-syn pathology and neurological dysfunction. Selective reduction of long-chain GSLs ameliorated α-syn pathology through lysosomal cathepsins. We identify specific requirements that dictate synuclein pathology in GD models, providing possible explanations for the phenotypic variability in subjects with GCase deficiency.
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Affiliation(s)
- Kristina Fredriksen
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611
| | - Stefanos Aivazidis
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611
| | - Karan Sharma
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611
| | - Kevin J Burbidge
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611
| | - Caleb Pitcairn
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611
| | - Friederike Zunke
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen 91054, Germany
| | - Eilrayna Gelyana
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611
| | - Joseph R Mazzulli
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611;
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30
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Wyse RK, Stott SRW, Mursaleen L, Matthews H, Dawson VL, Dawson TM. Waiting for PARIS-A Biological Target in Search of a Drug. JOURNAL OF PARKINSONS DISEASE 2021; 12:95-103. [PMID: 34744054 PMCID: PMC8842778 DOI: 10.3233/jpd-212945] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
A recent breakthrough paper published in Science Translational Medicine has provided compelling evidence that inhibition of Parkin Interacting Substrate (PARIS) may offer clinical researchers an important new therapeutic approach since it shows considerable promise as an important biological target potentially capable of pharmaceutical intervention to slow long term neurodegeneration in patients with Parkinson’s disease (PD). We present several PD-relevant perspectives on this paper that were not discussed in that otherwise entirely scientific narrative. We also outline the some of the work leading up to it, including the massive drug screen that proved necessary to discover a clinically suitable inhibitor of PARIS (Farnesol), as well as relevant PD research within the wider drug class, issues surrounding its future formulation, and next steps in translating this new knowledge into the clinic to evaluate possible long-term PD patient benefits.
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Affiliation(s)
| | | | | | | | - Valina L Dawson
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Ted M Dawson
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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31
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Teixeira M, Sheta R, Idi W, Oueslati A. Alpha-Synuclein and the Endolysosomal System in Parkinson's Disease: Guilty by Association. Biomolecules 2021; 11:biom11091333. [PMID: 34572546 PMCID: PMC8472725 DOI: 10.3390/biom11091333] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 09/06/2021] [Accepted: 09/06/2021] [Indexed: 12/13/2022] Open
Abstract
Abnormal accumulation of the protein α- synuclein (α-syn) into proteinaceous inclusions called Lewy bodies (LB) is the neuropathological hallmark of Parkinson's disease (PD) and related disorders. Interestingly, a growing body of evidence suggests that LB are also composed of other cellular components such as cellular membrane fragments and vesicular structures, suggesting that dysfunction of the endolysosomal system might also play a role in LB formation and neuronal degeneration. Yet the link between α-syn aggregation and the endolysosomal system disruption is not fully elucidated. In this review, we discuss the potential interaction between α-syn and the endolysosomal system and its impact on PD pathogenesis. We propose that the accumulation of monomeric and aggregated α-syn disrupt vesicles trafficking, docking, and recycling, leading to the impairment of the endolysosomal system, notably the autophagy-lysosomal degradation pathway. Reciprocally, PD-linked mutations in key endosomal/lysosomal machinery genes (LRRK2, GBA, ATP13A2) also contribute to increasing α-syn aggregation and LB formation. Altogether, these observations suggest a potential synergistic role of α-syn and the endolysosomal system in PD pathogenesis and represent a viable target for the development of disease-modifying treatment for PD and related disorders.
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Affiliation(s)
- Maxime Teixeira
- CHU de Québec Research Center, Axe Neurosciences, Quebec City, QC G1V 4G2, Canada; (M.T.); (R.S.); (W.I.)
- Department of Molecular Medicine, Faculty of Medicine, Université Laval, Quebec City, QC G1V 0A6, Canada
| | - Razan Sheta
- CHU de Québec Research Center, Axe Neurosciences, Quebec City, QC G1V 4G2, Canada; (M.T.); (R.S.); (W.I.)
- Department of Molecular Medicine, Faculty of Medicine, Université Laval, Quebec City, QC G1V 0A6, Canada
| | - Walid Idi
- CHU de Québec Research Center, Axe Neurosciences, Quebec City, QC G1V 4G2, Canada; (M.T.); (R.S.); (W.I.)
- Department of Molecular Medicine, Faculty of Medicine, Université Laval, Quebec City, QC G1V 0A6, Canada
| | - Abid Oueslati
- CHU de Québec Research Center, Axe Neurosciences, Quebec City, QC G1V 4G2, Canada; (M.T.); (R.S.); (W.I.)
- Department of Molecular Medicine, Faculty of Medicine, Université Laval, Quebec City, QC G1V 0A6, Canada
- Correspondence:
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32
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A conformational switch driven by phosphorylation regulates the activity of the evolutionarily conserved SNARE Ykt6. Proc Natl Acad Sci U S A 2021; 118:2016730118. [PMID: 33723042 PMCID: PMC8000380 DOI: 10.1073/pnas.2016730118] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Ykt6 is a conserved SNARE that plays critical roles along multiple vesicular pathways. To achieve its function, Ykt6 cycles between the cytosol and membrane-bound compartments through reversible lipidation. The mechanism that regulates these transitions is unknown. Ykt6 function is disrupted by α-synuclein, a protein critically implicated in synucleinopathies such as Parkinson’s Disease. Through a multidisciplinary approach, we report that phosphorylation regulated by Ca2+ signaling drives a conformational change that allows Ykt6 to switch from a closed cytosolic to an open membrane-bound form. Phosphorylation is also a critical determinant for Ykt6 protein interactions with functional consequences in the secretory and autophagy pathways under normal and α-synuclein conditions. This work provides a mechanistic insight into Ykt6 regulation with therapeutic implications for synucleinopathies. Ykt6 is a soluble N-ethylmaleimide sensitive factor activating protein receptor (SNARE) critically involved in diverse vesicular fusion pathways. While most SNAREs rely on transmembrane domains for their activity, Ykt6 dynamically cycles between the cytosol and membrane-bound compartments where it is active. The mechanism that regulates these transitions and allows Ykt6 to achieve specificity toward vesicular pathways is unknown. Using a Parkinson’s disease (PD) model, we found that Ykt6 is phosphorylated at an evolutionarily conserved site which is regulated by Ca2+ signaling. Through a multidisciplinary approach, we show that phosphorylation triggers a conformational change that allows Ykt6 to switch from a closed cytosolic to an open membrane-bound form. In the phosphorylated open form, the spectrum of protein interactions changes, leading to defects in both the secretory and autophagy pathways, enhancing toxicity in PD models. Our studies reveal a mechanism by which Ykt6 conformation and activity are regulated with potential implications for PD.
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33
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Mallucci GR, Klenerman D, Rubinsztein DC. Developing Therapies for Neurodegenerative Disorders: Insights from Protein Aggregation and Cellular Stress Responses. Annu Rev Cell Dev Biol 2021; 36:165-189. [PMID: 33021824 DOI: 10.1146/annurev-cellbio-040320-120625] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
As the world's population ages, neurodegenerative disorders are poised to become the commonest cause of death. Despite this, they remain essentially untreatable. Characterized pathologically both by the aggregation of disease-specific misfolded proteins and by changes in cellular stress responses, to date, therapeutic approaches have focused almost exclusively on reducing misfolded protein load-notably amyloid beta (Aβ) in Alzheimer's disease. The repeated failure of clinical trials has led to despondency over the possibility that these disorders will ever be treated. We argue that this is in fact a time for optimism: Targeting various generic stress responses is emerging as an increasingly promising means of modifying disease progression across these disorders. New treatments are approaching clinical trials, while novel means of targeting aggregates could eventually act preventively in early disease.
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Affiliation(s)
- Giovanna R Mallucci
- UK Dementia Research Institute at the University of Cambridge, Cambridge CB2 0AH, United Kingdom; .,Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0AH, United Kingdom
| | - David Klenerman
- UK Dementia Research Institute at the University of Cambridge, Cambridge CB2 0AH, United Kingdom; .,Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, United Kingdom
| | - David C Rubinsztein
- UK Dementia Research Institute at the University of Cambridge, Cambridge CB2 0AH, United Kingdom; .,Cambridge Institute for Medical Research, Cambridge CB2 0XY, United Kingdom
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34
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Sakata N, Shirakawa R, Goto K, Trinh DA, Horiuchi H. Double prenylation of SNARE protein Ykt6 is required for lysosomal hydrolase trafficking. J Biochem 2021; 169:363-370. [PMID: 33035318 DOI: 10.1093/jb/mvaa111] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Accepted: 09/18/2020] [Indexed: 11/14/2022] Open
Abstract
Ykt6 is an evolutionarily conserved SNARE protein regulating Golgi membrane fusion and other diverse membrane trafficking pathways. Unlike most SNARE proteins, Ykt6 lacks a transmembrane domain but instead has a tandem cysteine motif at the C-terminus. Recently, we have demonstrated that Ykt6 undergoes double prenylation at the C-terminal two cysteines first by farnesyltransferase and then by a newly identified protein prenyltransferase named geranylgeranyltransferase type-III (GGTase-III). GGTase-III consists of a novel α subunit prenyltransferase alpha subunit repeat containing 1 (PTAR1) and the β subunit of Rab geranylgeranyltransferase. PTAR1 knockout (KO) cells, where Ykt6 is singly prenylated with a farnesyl moiety, exhibit structural and functional abnormalities in the Golgi apparatus with delayed intra-Golgi trafficking and impaired protein glycosylation. It remains unclear whether the second prenylation of Ykt6 is required for proper trafficking of lysosomal hydrolases from Golgi to lysosomes. Here, we show that lysosomal hydrolases, cathepsin D and β-hexosaminidase, were missorted at the trans-Golgi network and secreted into the extracellular space in PTAR1 KO cells. Moreover, maturation of these hydrolases was disturbed. LC3B, an autophagy marker, was accumulated in PTAR1 KO cells, suggesting defects in cellular degradation pathways. Thus, doubly prenylated Ykt6, but not singly prenylated Ykt6, is critical for the efficient sorting and trafficking of acid hydrolases to lysosomes.
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Affiliation(s)
- Natsumi Sakata
- Department of Molecular and Cellular Biology, Institute of Development, Aging and Cancer, Tohoku University, Sendai 980-8575, Japan
| | - Ryutaro Shirakawa
- Department of Molecular and Cellular Biology, Institute of Development, Aging and Cancer, Tohoku University, Sendai 980-8575, Japan
| | - Kota Goto
- Department of Molecular and Cellular Biology, Institute of Development, Aging and Cancer, Tohoku University, Sendai 980-8575, Japan
| | - Duc Anh Trinh
- Department of Molecular and Cellular Biology, Institute of Development, Aging and Cancer, Tohoku University, Sendai 980-8575, Japan
| | - Hisanori Horiuchi
- Department of Molecular and Cellular Biology, Institute of Development, Aging and Cancer, Tohoku University, Sendai 980-8575, Japan
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α-synuclein pathogenesis in hiPSC models of Parkinson's disease. Neuronal Signal 2021; 5:NS20210021. [PMID: 34239711 PMCID: PMC8222967 DOI: 10.1042/ns20210021] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 06/08/2021] [Accepted: 06/14/2021] [Indexed: 12/17/2022] Open
Abstract
α-synuclein is an increasingly prominent player in the pathology of a variety of neurodegenerative conditions. Parkinson’s disease (PD) is a neurodegenerative disorder that affects mainly the dopaminergic (DA) neurons in the substantia nigra of the brain. Typical of PD pathology is the finding of protein aggregations termed ‘Lewy bodies’ in the brain regions affected. α-synuclein is implicated in many disease states including dementia with Lewy bodies (DLB) and Alzheimer’s disease. However, PD is the most common synucleinopathy and continues to be a significant focus of PD research in terms of the α-synuclein Lewy body pathology. Mutations in several genes are associated with PD development including SNCA, which encodes α-synuclein. A variety of model systems have been employed to study α-synuclein physiology and pathophysiology in an attempt to relate more closely to PD pathology. These models include cellular and animal system exploring transgenic technologies, viral vector expression and knockdown approaches, and models to study the potential prion protein-like effects of α-synuclein. The current review focuses on human induced pluripotent stem cell (iPSC) models with a specific focus on mutations or multiplications of the SNCA gene. iPSCs are a rapidly evolving technology with huge promise in the study of normal physiology and disease modeling in vitro. The ability to maintain a patient’s genetic background and replicate similar cell phenotypes make iPSCs a powerful tool in the study of neurological diseases. This review focuses on the current knowledge about α-synuclein physiological function as well as its role in PD pathogenesis based on human iPSC models.
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Abe T, Kuwahara T. Targeting of Lysosomal Pathway Genes for Parkinson's Disease Modification: Insights From Cellular and Animal Models. Front Neurol 2021; 12:681369. [PMID: 34194386 PMCID: PMC8236816 DOI: 10.3389/fneur.2021.681369] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 05/20/2021] [Indexed: 01/01/2023] Open
Abstract
Previous genetic studies on hereditary Parkinson's disease (PD) have identified a set of pathogenic gene mutations that have strong impacts on the pathogenicity of PD. In addition, genome-wide association studies (GWAS) targeted to sporadic PD have nominated an increasing number of genetic variants that influence PD susceptibility. Although the clinical and pathological characteristics in hereditary PD are not identical to those in sporadic PD, α-synuclein, and LRRK2 are definitely associated with both types of PD, with LRRK2 mutations being the most frequent cause of autosomal-dominant PD. On the other hand, a significant portion of risk genes identified from GWAS have been associated with lysosomal functions, pointing to a critical role of lysosomes in PD pathogenesis. Experimental studies have suggested that the maintenance or upregulation of lysosomal activity may protect against neuronal dysfunction or degeneration. Here we focus on the roles of representative PD gene products that are implicated in lysosomal pathway, namely LRRK2, VPS35, ATP13A2, and glucocerebrosidase, and provide an overview of their disease-associated functions as well as their cooperative actions in the pathogenesis of PD, based on the evidence from cellular and animal models. We also discuss future perspectives of targeting lysosomal activation as a possible strategy to treat neurodegeneration.
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Affiliation(s)
- Tetsuro Abe
- Department of Neuropathology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Tomoki Kuwahara
- Department of Neuropathology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
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Coccia E, Ahfeldt T. Towards physiologically relevant human pluripotent stem cell (hPSC) models of Parkinson's disease. Stem Cell Res Ther 2021; 12:253. [PMID: 33926571 PMCID: PMC8082939 DOI: 10.1186/s13287-021-02326-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 04/05/2021] [Indexed: 02/06/2023] Open
Abstract
The derivation of human embryonic stem cells followed by the discovery of induced pluripotent stem cells and leaps in genome editing approaches have continuously fueled enthusiasm for the development of new models of neurodegenerative diseases such as Parkinson's disease (PD). PD is characterized by the relative selective loss of dopaminergic neurons (DNs) in specific areas of substantia nigra pars compacta (SNpc). While degeneration in late stages can be widespread, there is stereotypic early degeneration of these uniquely vulnerable neurons. Various causes of selective vulnerability have been investigated but much remains unclear. Most studies have sought to identify cell autonomous properties of the most vulnerable neurons. However, recent findings from genetic studies and model systems have added to our understanding of non-cell autonomous contributions including regional-specific neuro-immune interactions with astrocytes, resident or damage-activated microglia, neuro-glia cell metabolic interactions, involvement of endothelial cells, and damage to the vascular system. All of these contribute to specific vulnerability and, along with aging and environmental factors, might be integrated in a complex stressor-threshold model of neurodegeneration. In this forward-looking review, we synthesize recent advances in the field of PD modeling using human pluripotent stem cells, with an emphasis on organoid and complex co-culture models of the nigrostriatal niche, with emerging CRISPR applications to edit or perturb expression of causal PD genes and associated risk factors, such as GBA, to understand the impact of these genes on relevant phenotypes.
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Affiliation(s)
- Elena Coccia
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, 10029, NY, US
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, 10029, NY, US
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, 10029, NY, US
- Ronald M. Loeb Center for Alzheimer's Disease, Icahn School of Medicine at Mount Sinai, New York, 10029, NY, US
- Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, 10029, NY, US
| | - Tim Ahfeldt
- Nash Family Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, 10029, NY, US.
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, 10029, NY, US.
- Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, 10029, NY, US.
- Ronald M. Loeb Center for Alzheimer's Disease, Icahn School of Medicine at Mount Sinai, New York, 10029, NY, US.
- Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, 10029, NY, US.
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Kim S, Wong YC, Gao F, Krainc D. Dysregulation of mitochondria-lysosome contacts by GBA1 dysfunction in dopaminergic neuronal models of Parkinson's disease. Nat Commun 2021; 12:1807. [PMID: 33753743 PMCID: PMC7985376 DOI: 10.1038/s41467-021-22113-3] [Citation(s) in RCA: 86] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 02/16/2021] [Indexed: 12/20/2022] Open
Abstract
Mitochondria-lysosome contacts are recently identified sites for mediating crosstalk between both organelles, but their role in normal and diseased human neurons remains unknown. In this study, we demonstrate that mitochondria-lysosome contacts can dynamically form in the soma, axons, and dendrites of human neurons, allowing for their bidirectional crosstalk. Parkinson's disease patient derived neurons harboring mutant GBA1 exhibited prolonged mitochondria-lysosome contacts due to defective modulation of the untethering protein TBC1D15, which mediates Rab7 GTP hydrolysis for contact untethering. This dysregulation was due to decreased GBA1 (β-glucocerebrosidase (GCase)) lysosomal enzyme activity in patient derived neurons, and could be rescued by increasing enzyme activity with a GCase modulator. These defects resulted in disrupted mitochondrial distribution and function, and could be further rescued by TBC1D15 in Parkinson's patient derived GBA1-linked neurons. Together, our work demonstrates a potential role of mitochondria-lysosome contacts as an upstream regulator of mitochondrial function and dynamics in midbrain dopaminergic neurons in GBA1-linked Parkinson's disease.
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Affiliation(s)
- Soojin Kim
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Yvette C Wong
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Fanding Gao
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Dimitri Krainc
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
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Abstract
Lysosomes are critical for maintaining protein homeostasis and cellular metabolism. Lysosomal dysfunction and disrupted protein trafficking contribute to cell death in neurodegenerative disorders, including Parkinson's disease and dementia. We describe three complementary protocols-the use of protein glycosylation, western blotting, immunofluorescence, and hydrolase activity measurement-to analyze the trafficking and activity of lysosomal proteins in patient-derived neurons differentiated from iPSCs. These methods should help to identify lysosomal phenotypes in patient-derived cultures and aid the discovery of therapeutics that augment lysosomal function. For complete details on the use and execution of this protocol, please refer to Cuddy et al. (2019).
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Modelling Parkinson's Disease: iPSCs towards Better Understanding of Human Pathology. Brain Sci 2021; 11:brainsci11030373. [PMID: 33799491 PMCID: PMC8000082 DOI: 10.3390/brainsci11030373] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 03/10/2021] [Accepted: 03/10/2021] [Indexed: 02/07/2023] Open
Abstract
Parkinson’s Disease (PD) is a chronic neurodegenerative disorder characterized by motor and non-motor symptoms, among which are bradykinesia, rigidity, tremor as well as mental symptoms such as dementia. The underlying cause of Parkinson disease is degeneration of dopaminergic neurons. It has been challenging to develop an efficient animal model to accurately represent the complex phenotypes found with PD. However, it has become possible to recapitulate the myriad of phenotypes underlying the PD pathology by using human induced pluripotent stem cell (iPSC) technology. Patient-specific iPSC-derived dopaminergic neurons are available and present an opportunity to study many aspects of the PD phenotypes in a dish. In this review, we report the available data on iPSC-derived neurons derived from PD patients with identified gene mutations. Specifically, we will report on the key phenotypes of the generated iPSC-derived neurons from PD patients with different genetic background. Furthermore, we discuss the relationship these cellular phenotypes have to PD pathology and future challenges and prospects for iPSC modelling and understanding of the pathogenesis of PD.
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Stojkovska I, Mazzulli JR. Detection of pathological alpha-synuclein aggregates in human iPSC-derived neurons and tissue. STAR Protoc 2021; 2:100372. [PMID: 33733241 PMCID: PMC7941090 DOI: 10.1016/j.xpro.2021.100372] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The accumulation of proteins into insoluble aggregates is a common feature of several neurodegenerative diseases. Aggregated α-synuclein is a major component of Lewy bodies that pathologically define Parkinson's disease (PD). Here, we present methods for the detection of pathogenic conformations of α-synuclein in induced pluripotent stem cell (iPSC) patient-derived neuron models and brain tissue. These methods can be applied to studies of PD pathogenesis and the discovery of novel therapeutics that restore physiological α-synuclein. For complete details on the use and execution of this protocol, please refer to Cuddy et al. (2019) and Zunke et al. (2018). α-Synuclein aggregates can be characterized by sequential protein extraction Protocol is optimized for detecting α-synuclein in iPSC-derived neurons or brain tissue Gel filtration is a useful method for the detection of oligomeric intermediates Inclusions can be further analyzed by immunofluorescence and Thioflavin S staining
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Affiliation(s)
- Iva Stojkovska
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
| | - Joseph R Mazzulli
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
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Grabowski GA, Antommaria AHM, Kolodny EH, Mistry PK. Gaucher disease: Basic and translational science needs for more complete therapy and management. Mol Genet Metab 2021; 132:59-75. [PMID: 33419694 PMCID: PMC8809485 DOI: 10.1016/j.ymgme.2020.12.291] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 11/15/2020] [Accepted: 12/18/2020] [Indexed: 12/12/2022]
Affiliation(s)
- Gregory A Grabowski
- Department of Pediatrics, University of Cincinnati College of Medicine, United States of America; Department of Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati College of Medicine, United States of America; Division of Human Genetics, Cincinnati Children's Research Foundation, Cincinnati, OH, United States of America.
| | - Armand H M Antommaria
- Department of Pediatrics, University of Cincinnati College of Medicine, United States of America; Lee Ault Carter Chair of Pediatric Ethics, Cincinnati Children's Research Foundation, Cincinnati, OH, United States of America.
| | - Edwin H Kolodny
- Department of Neurology, New York University Grossman School of Medicine, New York, NY, United States of America.
| | - Pramod K Mistry
- Departments of Medicine and Pediatrics, Yale School of Medicine, New Haven, CT, United States of America.
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Gao L, Wang W, Wang X, Yang F, Xie L, Shen J, Brimble MA, Xiao Q, Yao SQ. Fluorescent probes for bioimaging of potential biomarkers in Parkinson's disease. Chem Soc Rev 2021; 50:1219-1250. [DOI: 10.1039/d0cs00115e] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
This review comprehensively summarizes various types of fluorescent probes for PD and their applications for detection of various PD biomarkers.
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Affiliation(s)
- Liqian Gao
- School of Pharmaceutical Sciences (Shenzhen)
- Sun Yat-sen University
- Shenzhen, 518107
- P. R. China
- Department of Chemistry
| | - Wei Wang
- School of Pharmaceutical Sciences (Shenzhen)
- Sun Yat-sen University
- Shenzhen, 518107
- P. R. China
- Department of Chemistry
| | - Xuan Wang
- School of Pharmaceutical Sciences (Shenzhen)
- Sun Yat-sen University
- Shenzhen, 518107
- P. R. China
| | - Fen Yang
- School of Pharmaceutical Sciences (Shenzhen)
- Sun Yat-sen University
- Shenzhen, 518107
- P. R. China
| | - Liuxing Xie
- School of Pharmaceutical Sciences (Shenzhen)
- Sun Yat-sen University
- Shenzhen, 518107
- P. R. China
| | - Jun Shen
- Department of Radiology
- Sun Yat-Sen Memorial Hospital
- Sun Yat-Sen University
- Guangzhou
- P. R. China
| | - Margaret A. Brimble
- School of Chemical Sciences
- The University of Auckland
- Auckland 1010
- New Zealand
| | - Qicai Xiao
- School of Pharmaceutical Sciences (Shenzhen)
- Sun Yat-sen University
- Shenzhen, 518107
- P. R. China
- Department of Chemistry
| | - Shao Q. Yao
- Department of Chemistry
- National University of Singapore
- Singapore
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Minakaki G, Krainc D, Burbulla LF. The Convergence of Alpha-Synuclein, Mitochondrial, and Lysosomal Pathways in Vulnerability of Midbrain Dopaminergic Neurons in Parkinson's Disease. Front Cell Dev Biol 2020; 8:580634. [PMID: 33381501 PMCID: PMC7767856 DOI: 10.3389/fcell.2020.580634] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 11/10/2020] [Indexed: 12/15/2022] Open
Abstract
Parkinson's disease (PD) is the second most common neurodegenerative disease, characterized by progressive bradykinesia, rigidity, resting tremor, and gait impairment, as well as a spectrum of non-motor symptoms including autonomic and cognitive dysfunction. The cardinal motor symptoms of PD stem from the loss of substantia nigra (SN) dopaminergic (DAergic) neurons, and it remains unclear why SN DAergic neurons are preferentially lost in PD. However, recent identification of several genetic PD forms suggests that mitochondrial and lysosomal dysfunctions play important roles in the degeneration of midbrain dopamine (DA) neurons. In this review, we discuss the interplay of cell-autonomous mechanisms linked to DAergic neuron vulnerability and alpha-synuclein homeostasis. Emerging studies highlight a deleterious feedback cycle, with oxidative stress, altered DA metabolism, dysfunctional lysosomes, and pathological alpha-synuclein species representing key events in the pathogenesis of PD. We also discuss the interactions of alpha-synuclein with toxic DA metabolites, as well as the biochemical links between intracellular iron, calcium, and alpha-synuclein accumulation. We suggest that targeting multiple pathways, rather than individual processes, will be important for developing disease-modifying therapies. In this context, we focus on current translational efforts specifically targeting lysosomal function, as well as oxidative stress via calcium and iron modulation. These efforts could have therapeutic benefits for the broader population of sporadic PD and related synucleinopathies.
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Affiliation(s)
- Georgia Minakaki
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Dimitri Krainc
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Lena F Burbulla
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
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45
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Karuna M P, Witte L, Linnemannstoens K, Choezom D, Danieli-Mackay A, Honemann-Capito M, Gross JC. Phosphorylation of Ykt6 SNARE Domain Regulates Its Membrane Recruitment and Activity. Biomolecules 2020; 10:biom10111560. [PMID: 33207719 PMCID: PMC7696345 DOI: 10.3390/biom10111560] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 11/10/2020] [Accepted: 11/11/2020] [Indexed: 12/17/2022] Open
Abstract
Sensitive factor attachment protein receptors (SNARE) proteins are important mediators of protein trafficking that regulate the membrane fusion of specific vesicle populations and their target organelles. The SNARE protein Ykt6 lacks a transmembrane domain and attaches to different organelle membranes. Mechanistically, Ykt6 activity is thought to be regulated by a conformational change from a closed cytosolic form to an open membrane-bound form, yet the mechanism that regulates this transition is unknown. We identified phosphorylation sites in the SNARE domain of Ykt6 that mediate Ykt6 membrane recruitment and are essential for cellular growth. Using proximity-dependent labeling and membrane fractionation, we found that phosphorylation regulates Ykt6 conversion from a closed to an open conformation. This conformational switch recruits Ykt6 to several organelle membranes, where it functionally regulates the trafficking of Wnt proteins and extracellular vesicle secretion in a concentration-dependent manner. We propose that phosphorylation of its SNARE domain leads to a conformational switch from a cytosolic, auto-inhibited Ykt6 to an active SNARE at different membranes.
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Affiliation(s)
- Pradhipa Karuna M
- Hematology and Oncology, University Medical Center Goettingen, 37077 Goettingen, Germany; (P.K.M.); (L.W.); (K.L.); (D.C.); (A.D.-M.); (M.H.-C.)
- Developmental Biochemistry, University Medical Center Goettingen, 37077 Goettingen, Germany
| | - Leonie Witte
- Hematology and Oncology, University Medical Center Goettingen, 37077 Goettingen, Germany; (P.K.M.); (L.W.); (K.L.); (D.C.); (A.D.-M.); (M.H.-C.)
- Developmental Biochemistry, University Medical Center Goettingen, 37077 Goettingen, Germany
| | - Karen Linnemannstoens
- Hematology and Oncology, University Medical Center Goettingen, 37077 Goettingen, Germany; (P.K.M.); (L.W.); (K.L.); (D.C.); (A.D.-M.); (M.H.-C.)
- Developmental Biochemistry, University Medical Center Goettingen, 37077 Goettingen, Germany
| | - Dolma Choezom
- Hematology and Oncology, University Medical Center Goettingen, 37077 Goettingen, Germany; (P.K.M.); (L.W.); (K.L.); (D.C.); (A.D.-M.); (M.H.-C.)
- Developmental Biochemistry, University Medical Center Goettingen, 37077 Goettingen, Germany
| | - Adi Danieli-Mackay
- Hematology and Oncology, University Medical Center Goettingen, 37077 Goettingen, Germany; (P.K.M.); (L.W.); (K.L.); (D.C.); (A.D.-M.); (M.H.-C.)
- Developmental Biochemistry, University Medical Center Goettingen, 37077 Goettingen, Germany
| | - Mona Honemann-Capito
- Hematology and Oncology, University Medical Center Goettingen, 37077 Goettingen, Germany; (P.K.M.); (L.W.); (K.L.); (D.C.); (A.D.-M.); (M.H.-C.)
- Developmental Biochemistry, University Medical Center Goettingen, 37077 Goettingen, Germany
| | - Julia Christina Gross
- Hematology and Oncology, University Medical Center Goettingen, 37077 Goettingen, Germany; (P.K.M.); (L.W.); (K.L.); (D.C.); (A.D.-M.); (M.H.-C.)
- Developmental Biochemistry, University Medical Center Goettingen, 37077 Goettingen, Germany
- HMU Health and Medical University Potsdam, 14471 Potsdam, Germany
- Correspondence:
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46
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Ho GPH, Ramalingam N, Imberdis T, Wilkie EC, Dettmer U, Selkoe DJ. Upregulation of Cellular Palmitoylation Mitigates α-Synuclein Accumulation and Neurotoxicity. Mov Disord 2020; 36:348-359. [PMID: 33103814 DOI: 10.1002/mds.28346] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 09/29/2020] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Synucleinopathies, including Parkinson's disease (PD), are characterized by α-synuclein (αS) cytoplasmic inclusions. αS-dependent vesicle-trafficking defects are important in PD pathogenesis, but their mechanisms are not well understood. Protein palmitoylation, post-translational addition of the fatty acid palmitate to cysteines, promotes trafficking by anchoring specific proteins to the vesicle membrane. αS itself cannot be palmitoylated as it lacks cysteines, but it binds to membranes, where palmitoylation occurs, via an amphipathic helix. We hypothesized that abnormal αS membrane-binding impairs trafficking by disrupting palmitoylation. Accordingly, we investigated the therapeutic potential of increasing cellular palmitoylation. OBJECTIVES We asked whether upregulating palmitoylation by inhibiting the depalmitoylase acyl-protein-thioesterase-1 (APT1) ameliorates pathologic αS-mediated cellular phenotypes and sought to identify the mechanism. METHODS Using human neuroblastoma cells, rat neurons, and iPSC-derived PD patient neurons, we examined the effects of pharmacologic and genetic downregulation of APT1 on αS-associated phenotypes. RESULTS APT1 inhibition or knockdown decreased αS cytoplasmic inclusions, reduced αS serine-129 phosphorylation (a PD neuropathological marker), and protected against αS-dependent neurotoxicity. We identified the APT1 substrate microtubule-associated-protein-6 (MAP6), which binds to vesicles in a palmitoylation-dependent manner, as a key mediator of these effects. Mechanistically, we found that pathologic αS accelerated palmitate turnover on MAP6, suggesting that APT1 inhibition corrects a pathological αS-dependent palmitoylation deficit. We confirmed the disease relevance of this mechanism by demonstrating decreased MAP6 palmitoylation in neurons from αS gene triplication patients. CONCLUSIONS Our findings demonstrate a novel link between the fundamental process of palmitoylation and αS pathophysiology. Upregulating palmitoylation represents an unexplored therapeutic strategy for synucleinopathies. © 2020 International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Gary P H Ho
- Ann Romney Center for Neurologic Diseases, Department of Neurology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Nagendran Ramalingam
- Ann Romney Center for Neurologic Diseases, Department of Neurology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Thibaut Imberdis
- Ann Romney Center for Neurologic Diseases, Department of Neurology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Erin C Wilkie
- Ann Romney Center for Neurologic Diseases, Department of Neurology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Ulf Dettmer
- Ann Romney Center for Neurologic Diseases, Department of Neurology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Dennis J Selkoe
- Ann Romney Center for Neurologic Diseases, Department of Neurology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
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