251
|
Härd T, Lendel C. Inhibition of amyloid formation. J Mol Biol 2012; 421:441-65. [PMID: 22244855 DOI: 10.1016/j.jmb.2011.12.062] [Citation(s) in RCA: 215] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2011] [Revised: 12/28/2011] [Accepted: 12/29/2011] [Indexed: 12/26/2022]
Abstract
Amyloid is aggregated protein in the form of insoluble fibrils. Amyloid deposition in human tissue-amyloidosis-is associated with a number of diseases including all common dementias and type II diabetes. Considerable progress has been made to understand the mechanisms leading to amyloid formation. It is, however, not yet clear by which mechanisms amyloid and protein aggregates formed on the path to amyloid are cytotoxic. Strategies to prevent protein aggregation and amyloid formation are nevertheless, in many cases, promising and even successful. This review covers research on intervention of amyloidosis and highlights several examples of how inhibition of protein aggregation and amyloid formation has been achieved in practice. For instance, rational design can provide drugs that stabilize a native folded state of a protein, protein engineering can provide new binding proteins that sequester monomeric peptides from aggregation, small molecules and peptides can be designed to block aggregation or direct it into non-cytotoxic paths, and monoclonal antibodies have been developed for therapies towards neurodegenerative diseases based on inhibition of amyloid formation and clearance.
Collapse
Affiliation(s)
- Torleif Härd
- Department of Molecular Biology, Swedish University of Agricultural Sciences, SE-751 24 Uppsala, Sweden.
| | | |
Collapse
|
252
|
Cloutier M, Wellstead P. Dynamic modelling of protein and oxidative metabolisms simulates the pathogenesis of Parkinson's disease. IET Syst Biol 2012; 6:65-72. [DOI: 10.1049/iet-syb.2011.0075] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
|
253
|
Cloutier M, Middleton R, Wellstead P. Feedback motif for the pathogenesis of Parkinson's disease. IET Syst Biol 2012; 6:86-93. [DOI: 10.1049/iet-syb.2011.0076] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
|
254
|
Abstract
Parkinson's disease (PD) is a progressive neurodegenerative disorder that affects movement. Although many of the causes of PD remain unclear, a consistent finding is the abnormal accumulation of the protein α-synuclein. In a recent issue of Cell, Mazzuli et al. provide a molecular explanation for the unexpected link between PD and Gaucher's disease, a glycolipid lysosomal storage disorder caused by loss of the enzyme glucocerebrosidase (GBA). They report a reciprocal connection between loss of GBA activity and the accumulation of α-synuclein in lysosomes that establishes a bidirectional positive feedback loop with pathogenic consequences. Understanding how lysosomes are implicated in PD may reveal new therapeutic targets for treating this disease.
Collapse
Affiliation(s)
- Ted M Dawson
- Neuroregeneration Program, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
| | | |
Collapse
|
255
|
Bate C, Williams A. Ethanol protects cultured neurons against amyloid-β and α-synuclein-induced synapse damage. Neuropharmacology 2011; 61:1406-12. [DOI: 10.1016/j.neuropharm.2011.08.030] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2011] [Revised: 08/04/2011] [Accepted: 08/22/2011] [Indexed: 01/05/2023]
|
256
|
Bellucci A, Navarria L, Zaltieri M, Missale C, Spano P. α-Synuclein synaptic pathology and its implications in the development of novel therapeutic approaches to cure Parkinson's disease. Brain Res 2011; 1432:95-113. [PMID: 22153624 DOI: 10.1016/j.brainres.2011.11.031] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2011] [Revised: 11/11/2011] [Accepted: 11/11/2011] [Indexed: 12/24/2022]
Abstract
Parkinson's disease (PD) is characterized by a progressive loss of dopamine (DA) neurons of the nigrostriatal system and by the presence of Lewy bodies (LB), proteinaceous inclusions mainly composed of filamentous α-synuclein aggregates. Alpha-synuclein is a natively unfolded protein which plays a central role in the control of dopaminergic neuronal functions and which is thought to be critically implicated in PD pathophysiology. Indeed, besides the fact that α-synuclein is the main protein component of LB, genetic studies showed that mutations and multiplications of the α-synuclein gene are responsible for the onset of familial forms of PD. A large body of evidence indicates that α-synuclein pathology at dopaminergic synapses may underlie the onset of neuronal cell dysfunction and degeneration in the PD brain. Thus, since the available therapeutic approaches to cure this disease are still limited, we hypothesized that the analysis of the α-synuclein synaptic proteome/lipidome may represent a tool to identify novel potential therapeutic targets to cure this disorder. We thus performed a critical review of studies describing α-synuclein pathophysiology at synaptic sites in experimental models of PD and in this paper we outline the most relevant findings regarding the specific modulatory effects exerted by α-synuclein in the control of synaptic functions in physiological and pathological conditions. The conclusions of these studies allow to single out novel potential therapeutic targets among the α-synuclein synaptic partners. These targets may be considered for the development of new pharmacological and gene-based strategies to cure PD.
Collapse
Affiliation(s)
- Arianna Bellucci
- Division of Pharmacology, Department of Biomedical Sciences and Biotechnology and National Institute of Neuroscience - Italy, School of Medicine, University of Brescia, Brescia, Italy.
| | | | | | | | | |
Collapse
|
257
|
Yakunin E, Loeb V, Kisos H, Biala Y, Yehuda S, Yaari Y, Selkoe DJ, Sharon R. Α-synuclein neuropathology is controlled by nuclear hormone receptors and enhanced by docosahexaenoic acid in a mouse model for Parkinson's disease. Brain Pathol 2011; 22:280-94. [PMID: 21929559 DOI: 10.1111/j.1750-3639.2011.00530.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
α-Synuclein (α-Syn) is a neuronal protein that accumulates progressively in Parkinson's disease (PD) and related synucleinopathies. Attempting to identify cellular factors that affect α-Syn neuropathology, we previously reported that polyunsaturated fatty acids (PUFAs) promote α-Syn oligomerization and aggregation in cultured cells. We now report that docosahexaenoic acid (DHA), a 22:6 PUFA, affects α-Syn oligomerization by activating retinoic X receptor (RXR) and peroxisome proliferator-activated receptor γ2 (PPARγ2). In addition, we show that dietary changes in brain DHA levels affect α-Syn cytopathology in mice transgenic for the PD-causing A53T mutation in human α-Syn. A diet enriched in DHA, an activating ligand of RXR, increased the accumulation of soluble and insoluble neuronal α-Syn, neuritic injury and astrocytosis. Conversely, abnormal accumulations of α-Syn and its deleterious effects were significantly attenuated by low dietary DHA levels. Our results suggest a role for activated RXR/PPARγ 2, obtained by elevated brain PUFA levels, in α-Syn neuropathology.
Collapse
Affiliation(s)
- Eugenia Yakunin
- Department of Biochemistry and Molecular Biology, IMRIC, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | | | | | | | | | | | | | | |
Collapse
|
258
|
Yap TL, Gruschus JM, Velayati A, Westbroek W, Goldin E, Moaven N, Sidransky E, Lee JC. Alpha-synuclein interacts with Glucocerebrosidase providing a molecular link between Parkinson and Gaucher diseases. J Biol Chem 2011; 286:28080-8. [PMID: 21653695 PMCID: PMC3151053 DOI: 10.1074/jbc.m111.237859] [Citation(s) in RCA: 135] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2011] [Revised: 06/03/2011] [Indexed: 01/26/2023] Open
Abstract
The presynaptic protein α-synuclein (α-syn), particularly in its amyloid form, is widely recognized for its involvement in Parkinson disease (PD). Recent genetic studies reveal that mutations in the gene GBA are the most widespread genetic risk factor for parkinsonism identified to date. GBA encodes for glucocerebrosidase (GCase), the enzyme deficient in the lysosomal storage disorder, Gaucher disease (GD). In this work, we investigated the possibility of a physical linkage between α-syn and GCase, examining both wild type and the GD-related N370S mutant enzyme. Using fluorescence and nuclear magnetic resonance spectroscopy, we determined that α-syn and GCase interact selectively under lysosomal solution conditions (pH 5.5) and mapped the interaction site to the α-syn C-terminal residues, 118-137. This α-syn-GCase complex does not form at pH 7.4 and is stabilized by electrostatics, with dissociation constants ranging from 1.2 to 22 μm in the presence of 25 to 100 mm NaCl. Intriguingly, the N370S mutant form of GCase has a reduced affinity for α-syn, as does the inhibitor conduritol-β-epoxide-bound enzyme. Immunoprecipitation and immunofluorescence studies verified this interaction in human tissue and neuronal cell culture, respectively. Although our data do not preclude protein-protein interactions in other cellular milieux, we suggest that the α-syn-GCase association is favored in the lysosome, and that this noncovalent interaction provides the groundwork to explore molecular mechanisms linking PD with mutant GBA alleles.
Collapse
Affiliation(s)
- Thai Leong Yap
- From the Laboratory of Molecular Biophysics, National Heart Lung and Blood Institute, and
| | - James M. Gruschus
- From the Laboratory of Molecular Biophysics, National Heart Lung and Blood Institute, and
| | - Arash Velayati
- the Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland 20892
| | - Wendy Westbroek
- the Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland 20892
| | - Ehud Goldin
- the Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland 20892
| | - Nima Moaven
- the Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland 20892
| | - Ellen Sidransky
- the Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland 20892
| | - Jennifer C. Lee
- From the Laboratory of Molecular Biophysics, National Heart Lung and Blood Institute, and
| |
Collapse
|
259
|
Gao HM, Hong JS. Gene-environment interactions: key to unraveling the mystery of Parkinson's disease. Prog Neurobiol 2011; 94:1-19. [PMID: 21439347 PMCID: PMC3098527 DOI: 10.1016/j.pneurobio.2011.03.005] [Citation(s) in RCA: 123] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2010] [Revised: 01/26/2011] [Accepted: 03/16/2011] [Indexed: 12/21/2022]
Abstract
Parkinson's disease (PD) is the second most common neurodegenerative disease. The gradual, irreversible loss of dopamine neurons in the substantia nigra is the signature lesion of PD. Clinical symptoms of PD become apparent when 50-60% of nigral dopamine neurons are lost. PD progresses insidiously for 5-7 years (preclinical period) and then continues to worsen even under the symptomatic treatment. To determine what triggers the disease onset and what drives the chronic, self-propelling neurodegenerative process becomes critical and urgent, since lack of such knowledge impedes the discovery of effective treatments to retard PD progression. At present, available therapeutics only temporarily relieve PD symptoms. While the identification of causative gene defects in familial PD uncovers important genetic influences in this disease, the majority of PD cases are sporadic and idiopathic. The current consensus suggests that PD develops from multiple risk factors including aging, genetic predisposition, and environmental exposure. Here, we briefly review research on the genetic and environmental causes of PD. We also summarize very recent genome-wide association studies on risk gene polymorphisms in the emergence of PD. We highlight the new converging evidence on gene-environment interplay in the development of PD with an emphasis on newly developed multiple-hit PD models involving both genetic lesions and environmental triggers.
Collapse
Affiliation(s)
- Hui-Ming Gao
- Neuropharmacology Section, Laboratory of Toxicology & Pharmacology, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA.
| | | |
Collapse
|
260
|
Israeli E, Yakunin E, Zarbiv Y, Hacohen-Solovich A, Kisos H, Loeb V, Lichtenstein M, Ben-Gedalya T, Sabag O, Pikarsky E, Lorberboum-Galski H, Sharon R. α-Synuclein expression selectively affects tumorigenesis in mice modeling Parkinson's disease. PLoS One 2011; 6:e19622. [PMID: 21611169 PMCID: PMC3097187 DOI: 10.1371/journal.pone.0019622] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2011] [Accepted: 04/04/2011] [Indexed: 12/17/2022] Open
Abstract
Alpha Synuclein (α-Syn) is a protein implicated in mechanisms of neuronal degeneration in Parkinson's disease (PD). α-Syn is primarily a neuronal protein, however, its expression is found in various tumors including ovarian, colorectal and melanoma tumors. It has been hypothesized that neurodegeneration may share common mechanisms with oncogenesis. We tested whether α-Syn expression affects tumorigenesis of three types of tumors. Specifically, B16 melanoma, E0771 mammary gland adenocarcinoma and D122 Lewis lung carcinoma. For this aim, we utilized transgenic mice expression the human A53T α-Syn form. We found that the in vivo growth of B16 and E0771 but not D122 was enhanced in the A53T α-Syn mice. The effect on tumorigenesis was not detected in age-matched APP/PS1 mice, modeling Alzheimer's disease (AD), suggesting a specific effect for α-Syn- dependent neurodegeneration. Importantly, transgenic α-Syn expression was detected within the three tumor types. We further show uptake of exogenously added, purified α-Syn, by the cultured tumor cells. In accord, with the affected tumorigenesis in the young A53T α-Syn mice, over- expression of α-Syn in cultured B16 and E0771 cells enhanced proliferation, however, had no effect on the proliferation of D122 cells. Based on these results, we suggest that certain forms of α-Syn may selectively accelerate cellular mechanisms leading to cancer.
Collapse
Affiliation(s)
- Eitan Israeli
- Department of Biochemistry and Molecular Biology, IMRIC, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Eugenia Yakunin
- Department of Biochemistry and Molecular Biology, IMRIC, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Yonaton Zarbiv
- Department of Biochemistry and Molecular Biology, IMRIC, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Amir Hacohen-Solovich
- Department of Biochemistry and Molecular Biology, IMRIC, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Haya Kisos
- Department of Biochemistry and Molecular Biology, IMRIC, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Virginie Loeb
- Department of Biochemistry and Molecular Biology, IMRIC, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Michal Lichtenstein
- Department of Biochemistry and Molecular Biology, IMRIC, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Tziona Ben-Gedalya
- Developmental Biology and Cancer Research, IMRIC, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Ofra Sabag
- Department of Biochemistry and Molecular Biology, IMRIC, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Eli Pikarsky
- Developmental Biology and Cancer Research, IMRIC, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Haya Lorberboum-Galski
- Department of Biochemistry and Molecular Biology, IMRIC, Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Ronit Sharon
- Department of Biochemistry and Molecular Biology, IMRIC, Hebrew University-Hadassah Medical School, Jerusalem, Israel
- * E-mail:
| |
Collapse
|
261
|
Khodr CE, Sapru MK, Pedapati J, Han Y, West NC, Kells AP, Bankiewicz KS, Bohn MC. An α-synuclein AAV gene silencing vector ameliorates a behavioral deficit in a rat model of Parkinson's disease, but displays toxicity in dopamine neurons. Brain Res 2011; 1395:94-107. [PMID: 21565333 DOI: 10.1016/j.brainres.2011.04.036] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2011] [Accepted: 04/19/2011] [Indexed: 12/16/2022]
Abstract
Effects of silencing ectopically expressed hSNCA in rat substantia nigra (SN) were examined as a novel therapeutic approach to Parkinson's disease (PD). AAV-hSNCA with or without an AAV harboring a short-hairpin (sh)RNA targeting hSNCA or luciferase was injected into one SN. At 9weeks, hSNCA-expressing rats had reduced SN dopamine (DA) neurons and exhibited a forelimb deficit. AAV-shRNA-SNCA silenced hSNCA and protected against the forelimb deficit. However, AAV-shRNA-SNCA also led to DA neuron loss suggesting undesirable effects of chronic shRNA expression. Effects on nigrostriatal-projecting neurons were examined using a retrograde tract tracer. Loss of striatal-projecting DA neurons was evident in the vector injection site, whereas DA neurons outside this site were lost in hSNCA-expressing rats, but not in hSNCA-silenced rats. These observations suggest that high levels of shRNA-SNCA were toxic to DA neurons, while neighboring neurons exposed to lower levels were protected by hSNCA gene silencing. Also, data collected on DA levels suggest that neurons other than or in addition to nigrostriatal DA neurons contributed to protection of forelimb use. Our observations suggest that while hSNCA gene silencing in DA neurons holds promise as a novel PD therapy, further development of silencing technology is required.
Collapse
Affiliation(s)
- Christina E Khodr
- Department of Pediatrics, Neurobiology Program, Children's Memorial Research Center, Feinberg School of Medicine, Northwestern University, 2300 Children's Plaza, Box 209, Chicago, IL 60614, USA
| | | | | | | | | | | | | | | |
Collapse
|
262
|
Abstract
Parkinson’s disease is a neurodegenerative movement disorder characterized by loss of midbrain dopaminergic neurons leading to motor abnormalities and autonomic dysfunctions. Despite intensive research, the etiology of Parkinson’s disease remains poorly understood leaving us with no effective therapeutic options. However, the recent identification of genes linked to heritable forms of Parkinson’s disease has revolutionized research in the field and has begun to provide new clues to disease pathogenesis. Here we discuss these recent genetic advances and highlight their significance in our quest to better understand common underlying disease mechanisms that will help us identify innovative neuroprotective therapies for Parkinson’s disease.
Collapse
Affiliation(s)
- Bobby Thomas
- Department of Neurology and Neuroscience, Weill Medical College of Cornell University 525 East 68th Street, A-501, New York, NY 10065 USA
| | | |
Collapse
|
263
|
Dillin A, Cohen E. Ageing and protein aggregation-mediated disorders: from invertebrates to mammals. Philos Trans R Soc Lond B Biol Sci 2011; 366:94-8. [PMID: 21115535 DOI: 10.1098/rstb.2010.0271] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Late onset is a common hallmark character of numerous disorders including human neurodegenerative maladies such as Huntington's, Parkinson's and Alzheimer's diseases. Why these diseases manifest in aged individuals and why distinct disorders share strikingly similar emergence patterns were until recently unsolved enigmas. During the past decade, invertebrate-based studies indicated that the insulin/IGF signalling pathway (IIS) mechanistically links neurodegenerative-associated toxic protein aggregation and ageing; yet, until recently it was unclear whether this link is conserved from invertebrates to mammals. Recent studies performed in Alzheimer's mouse models indicated that ageing alteration by IIS reduction slows the progression of Alzheimer's-like disease, protects the brain and mitigates the behavioural, pathological and biochemical impairments associated with the disease. Here, we review these novel studies and discuss the potential of ageing alteration as a therapeutic approach for the treatment of late onset neurodegeneration.
Collapse
Affiliation(s)
- Andrew Dillin
- Howard Hughes Medical Institute, Glenn Center for Ageing Research, Molecular and Cell Biology Laboratory, The Salk Institute for Biological Studies , 10010 North Torrey Pines Road, La Jolla, CA 92037, USA.
| | | |
Collapse
|
264
|
Unal-Cevik I, Gursoy-Ozdemir Y, Yemisci M, Lule S, Gurer G, Can A, Müller V, Kahle PJ, Dalkara T. Alpha-synuclein aggregation induced by brief ischemia negatively impacts neuronal survival in vivo: a study in [A30P]alpha-synuclein transgenic mouse. J Cereb Blood Flow Metab 2011; 31:913-23. [PMID: 20877387 PMCID: PMC3063624 DOI: 10.1038/jcbfm.2010.170] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Alpha-synuclein oligomerization and aggregation are considered to have a role in the pathogenesis of neurodegenerative diseases. However, despite numerous in vitro studies, the impact of aggregates in the intact brain is unclear. In vitro, oxidative/nitrative stress and acidity induce α-synuclein oligomerization. These conditions favoring α-synuclein fibrillization are present in the ischemic brain, which may serve as an in vivo model to study α-synuclein aggregation. In this study, we show that 30-minute proximal middle cerebral artery (MCA) occlusion and 72 hours reperfusion induce oligomerization of wild-type α-synuclein in the ischemic mouse brain. The nonamyloidogenic isoform β-synuclein did not form oligomers. Alpha-synuclein aggregates were confined to neurons and colocalized with ubiquitin immunoreactivity. We also found that 30 minutes proximal MCA occlusion and 24 hours reperfusion induced larger infarcts in C57BL/6(Thy1)-h[A30P]alphaSYN transgenic mice, which have an increased tendency to form synuclein fibrils. Trangenics also developed more selective neuronal necrosis when subjected to 20 minutes distal MCA occlusion and 72 hours reperfusion. Enhanced 3-nitrotyrosine immunoreactivity in transgenic mice suggests that oxidative/nitrative stress may be one of the mechanisms mediating aggregate toxicity. Thus, the increased vulnerability of transgenic mice to ischemia suggests that α-synuclein aggregates not only form during ischemia but also negatively impact neuronal survival, supporting the idea that α-synuclein misfolding may be neurotoxic.
Collapse
Affiliation(s)
- Isin Unal-Cevik
- Department of Neurology, Faculty of Medicine, Hacettepe University, Ankara, Turkey
| | | | | | | | | | | | | | | | | |
Collapse
|
265
|
Alvarez-Erviti L, Seow Y, Schapira AH, Gardiner C, Sargent IL, Wood MJA, Cooper JM. Lysosomal dysfunction increases exosome-mediated alpha-synuclein release and transmission. Neurobiol Dis 2011; 42:360-7. [PMID: 21303699 PMCID: PMC3107939 DOI: 10.1016/j.nbd.2011.01.029] [Citation(s) in RCA: 545] [Impact Index Per Article: 41.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2010] [Revised: 01/19/2011] [Accepted: 01/28/2011] [Indexed: 01/02/2023] Open
Abstract
Alpha-synuclein aggregation plays a central role in Parkinson's disease pathology. Direct transmission of alpha-synuclein from pathologically affected to healthy unaffected neurons may be important in the anatomical spread of the disease through the nervous system. We have demonstrated that exosomes released from alpha-synuclein over-expressing SH-SY5Y cells contained alpha-synuclein and these exosomes were capable of efficiently transferring alpha-synuclein protein to normal SH-SY5Y cells. Moreover, the incubation of cells with ammonium chloride or bafilomycin A1 to produce the lysosomal dysfunction recently reported in Parkinson's disease led to an increase in the release of alpha-synuclein in exosomes and a concomitant increase in alpha-synuclein transmission to recipient cells. This study clearly demonstrates the importance of exosomes in both the release of alpha synuclein and its transmission between cells and suggests that factors associated with PD pathology accelerate this process. These mechanisms may play an important role in PD pathology and provide a suitable target for therapeutic intervention.
Collapse
Affiliation(s)
- Lydia Alvarez-Erviti
- University Department of Clinical Neurosciences, Institute of Neurology, University College London, UK.
| | | | | | | | | | | | | |
Collapse
|
266
|
Chadchankar H, Ihalainen J, Tanila H, Yavich L. Decreased reuptake of dopamine in the dorsal striatum in the absence of α-synuclein. Brain Res 2011; 1382:37-44. [PMID: 21276428 DOI: 10.1016/j.brainres.2011.01.064] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2010] [Revised: 01/17/2011] [Accepted: 01/19/2011] [Indexed: 10/18/2022]
Abstract
The presynaptic protein alpha-synuclein (α-syn) plays a role in dopaminergic neurotransmission in the nigrostriatal dopaminergic system. Mutations in this protein have been linked to pathogenesis of Parkinson's disease. However, the details of regulation of dopamine homeostasis by α-syn and its molecular targets are generally unknown. We investigated the effect of α-syn deletion on striatal dopaminergic homeostasis. Two α-syn deficient mouse lines, one carrying a spontaneous deletion of α-syn locus and the other a transgenic α-syn knockout, were used in the study. Stimulated and basal extracellular dopamine levels were determined in the dorsal striatum by in vivo voltammetry and in vivo microdialysis, respectively. Dopamine transporter expression was studied by immunohistochemistry. Stimulated dopamine overflow and basal extracellular dopamine levels were higher in mice lacking α-syn with a concomitant decrease in dopamine transporter expression and reuptake in the dorsal striatum. We show that α-syn deletion produces significant adaptive changes in the striatal dopaminergic system via modulation of reuptake.
Collapse
Affiliation(s)
- Heramb Chadchankar
- School of Pharmacy, Faculty of Health Sciences, P. O. Box 1627, University of Eastern Finland, Kuopio Campus, Kuopio 70211, Finland.
| | | | | | | |
Collapse
|
267
|
Alvarez-Erviti L, Couch Y, Richardson J, Cooper JM, Wood MJA. Alpha-synuclein release by neurons activates the inflammatory response in a microglial cell line. Neurosci Res 2011; 69:337-42. [PMID: 21255620 DOI: 10.1016/j.neures.2010.12.020] [Citation(s) in RCA: 148] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2010] [Revised: 12/17/2010] [Accepted: 12/22/2010] [Indexed: 01/14/2023]
Abstract
The neurodegenerative process in Parkinson's disease (PD) is accompanied by the presence of a neuroinflammatory response, which has been suggested as one of the principal components involved in PD progression. In this report we assessed the inflammatory potential of alpha-synuclein, a protein central to PD pathogenesis, released by neurons on the mouse microglia cell line BV-2. BV-2 cells were treated with conditioned medium isolated from normal SH-SY5Y cells and clones that over-express WT or mutant A53T alpha-synuclein. Conditioned medium isolated from over-expressing clones induced the transcription and release of pro-inflammatory cytokines. Treatment of SH-SY5Y alpha-synuclein over-expressing cells with MPP+, the active metabolite of the neurotoxin MPTP, increased the inflammatory response in BV-2 cells. In contrast, the direct exposure of BV-2 cells to MPP+ failed to induce an inflammatory response. These results support the hypothesis that WT and A53T alpha-synuclein has an important role in the initiation and maintenance of inflammation in PD, through the activation of a pro-inflammatory response in microglial cells.
Collapse
Affiliation(s)
- Lydia Alvarez-Erviti
- Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford OX1 3QX, UK.
| | | | | | | | | |
Collapse
|
268
|
Trancikova A, Ramonet D, Moore DJ. Genetic Mouse Models of Neurodegenerative Diseases. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2011; 100:419-82. [DOI: 10.1016/b978-0-12-384878-9.00012-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
|
269
|
Abstract
Genetic studies have provided valuable insight into the pathological mechanisms underlying Parkinson's disease (PD). The elucidation of genetic components to what was once largely considered a nongenetic disease has given rise to a multitude of cell and animal models enabling the dissection of molecular pathways involved in disease etiology. Here, we review advances obtained from models of dominant mutations in α-synuclein and LRRK2 as well as recessive PINK1, parkin and DJ-1 mutations. Recent genome-wide association studies have implicated genetic variability at two of these loci, α-synuclein and LRRK2, as significant risk factors for developing sporadic PD. This, coupled with the established role of mitochondrial impairment in both familial and sporadic PD, highlights the likelihood of common mechanisms fundamental to the etiology of both.
Collapse
Affiliation(s)
- Ian Martin
- NeuroRegeneration and Stem Cell Programs, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Valina L. Dawson
- NeuroRegeneration and Stem Cell Programs, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Ted M. Dawson
- NeuroRegeneration and Stem Cell Programs, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| |
Collapse
|
270
|
Monitoring of Cellular Dynamics with Electrochemical Detection Techniques. MODERN ASPECTS OF ELECTROCHEMISTRY 2011. [DOI: 10.1007/978-1-4614-0347-0_1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
|
271
|
Hisahara S, Shimohama S. Toxin-induced and genetic animal models of Parkinson's disease. PARKINSONS DISEASE 2010; 2011:951709. [PMID: 21234368 PMCID: PMC3014721 DOI: 10.4061/2011/951709] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 10/13/2010] [Accepted: 10/31/2010] [Indexed: 12/21/2022]
Abstract
Parkinson's disease (PD) is a common progressive neurodegenerative disorder. The major pathological hallmarks of PD are the selective loss of nigrostriatal dopaminergic neurons and the presence of intraneuronal aggregates termed Lewy bodies (LBs), but the pathophysiological mechanisms are not fully understood. Epidemiologically, environmental neurotoxins such as pesticides are promising candidates for causative factors of PD. Oxidative stress and mitochondrial dysfunction induced by these toxins could contribute to the progression of PD. While most cases of PD are sporadic, specific mutations in genes that cause familial forms of PD have led to provide new insights into its pathogenesis. This paper focuses on animal models of both toxin-induced and genetically determined PD that have provided significant insight for understanding this disease. We also discuss the validity, benefits, and limitations of representative models.
Collapse
Affiliation(s)
- Shin Hisahara
- Department of Neurology, Sapporo Medical University, South1, West17, chuo-ku, Sapporo 060-8556, Japan
| | | |
Collapse
|
272
|
Waxman EA, Giasson BI. Characterization of kinases involved in the phosphorylation of aggregated α-synuclein. J Neurosci Res 2010; 89:231-47. [PMID: 21162130 DOI: 10.1002/jnr.22537] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2010] [Revised: 09/30/2010] [Accepted: 10/08/2010] [Indexed: 12/31/2022]
Abstract
α-Synuclein (α-syn) is the major component of pathological inclusions characteristic of several neurodegenerative disorders, such as Parkinson's disease. The major posttranslational modification of α-syn is phosphorylation at S129, and previous studies estimate that approximately 90% of α-syn in proteinaceous, pathological inclusions is phosphorylated at this site. α-Syn can be phosphorylated by polo-like kinases (PLKs) 1-3 and casein kinases (CK) 1 and 2; however, the kinases associated with the hyperphosphorylation of aggregated α-syn are still under debate. Using a high-efficiency cellular model of α-syn aggregate formation, we found that selective inhibitors for CK2 and PLKs each partially inhibited S129 phosphorylation of soluble (nonaggregated) α-syn, but only PLK inhibitors modestly attenuated the phosphorylation of aggregated α-syn. In addition, none of the kinase inhibitors used had a substantial effect on the propensity of α-syn to aggregate. Overexpression of all PLKs promoted robust phosphorylation of soluble α-syn, but none altered the propensity of α-syn to aggregate. Overexpression of only PLK2 increased phosphorylation of aggregated α-syn at S129, which likely is due to increased phosphorylation of soluble α-syn, which then was incorporated into aggregates. Overexpression of PLK1 and treatment with BI2536 resulted in a significant reduction of phosphorylated, aggregated α-syn protein, beyond that of BI2536 treatment alone. These studies suggest that phosphorylation of α-syn is independent of α-syn aggregate formation, that PLK1 is involved in the phosphorylation of aggregated α-syn at S129 in this system, and that mechanisms resulting in hyperphosphorylation of aggregated α-syn appear to be independent of those responsible for the phosphorylation of soluble α-syn.
Collapse
Affiliation(s)
- Elisa A Waxman
- Department of Pharmacology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | | |
Collapse
|
273
|
α-synuclein induced synapse damage is enhanced by amyloid-β1-42. Mol Neurodegener 2010; 5:55. [PMID: 21138585 PMCID: PMC3017026 DOI: 10.1186/1750-1326-5-55] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2010] [Accepted: 12/07/2010] [Indexed: 11/24/2022] Open
Abstract
Background The pathogenesis of Parkinson's disease (PD) and dementia with Lewy bodies (DLB) is associated with the accumulation of aggregated forms of the α-synuclein (αSN) protein. An early event in the neuropathology of PD and DLB is the loss of synapses and a corresponding reduction in the level of synaptic proteins. However, the molecular mechanisms involved in synapse damage in these diseases are poorly understood. In this study the process of synapse damage was investigated by measuring the amount of synaptophysin, a pre-synaptic membrane protein essential for neurotransmission, in cultured neurons incubated with αSN, or with amyloid-β (Aβ) peptides that are thought to trigger synapse degeneration in Alzheimer's disease. Results We report that the addition of recombinant human αSN reduced the amount of synaptophysin in cultured cortical and hippocampal neurons indicative of synapse damage. αSN also reduced synaptic vesicle recycling, as measured by the uptake of the fluorescent dye FM1-43. These effects of αSN on synapses were modified by interactions with other proteins. Thus, the addition of βSN reduced the effects of αSN on synapses. In contrast, the addition of amyloid-β (Aβ)1-42 exacerbated the effects of αSN on synaptic vesicle recycling and synapse damage. Similarly, the addition of αSN increased synapse damage induced by Aβ1-42. However, this effect of αSN was selective as it did not affect synapse damage induced by the prion-derived peptide PrP82-146. Conclusions These results are consistent with the hypothesis that oligomers of αSN trigger synapse damage in the brains of Parkinson's disease patients. Moreover, they suggest that the effect of αSN on synapses may be influenced by interactions with other peptides produced within the brain.
Collapse
|
274
|
Castellani RJ, Nugent SL, Morrison AL, Zhu X, Lee HG, Harris PLR, Bajić V, Sharma HS, Chen SG, Oettgen P, Perry G, Smith MA. CD3 in Lewy pathology: does the abnormal recall of neurodevelopmental processes underlie Parkinson's disease. J Neural Transm (Vienna) 2010; 118:23-6. [PMID: 20972807 DOI: 10.1007/s00702-010-0485-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2010] [Accepted: 08/30/2010] [Indexed: 11/28/2022]
Abstract
CD3ζ is a subunit of the CD3 molecule that, until recently, appeared restricted to T cells and natural killer cells. However, experimental studies have demonstrated a role of CD3ζ in dendritic outgrowth in the visual system as well as in synaptic plasticity. Given the increasing evidence for uncharacteristic recapitulation of neurodevelopmental processes in neurodegenerative diseases, in this study, we evaluated brains from subjects with Parkinson's disease and Lewy body dementia for evidence of aberrant CD3 expression. Our data shows marked CD3ζ in association with the α-synuclein containing pathological lesions, i.e., Lewy bodies and Lewy neurites, in the brains of subjects with Parkinson's disease and Lewy body dementia. This finding raises the novel concept of CD3 dysregulation in these disorders as a pathogenic factor and also furthers the increasing evidence that the recall of aberrant neurodevelopmental processes underlies the pathogenesis of neurodegenerative diseases.
Collapse
Affiliation(s)
- Rudy J Castellani
- Department of Pathology, University of Maryland, 22 South Greene Street, Baltimore, MD 21201, USA.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
275
|
McCormack AL, Mak SK, Henderson JM, Bumcrot D, Farrer MJ, Di Monte DA. Alpha-synuclein suppression by targeted small interfering RNA in the primate substantia nigra. PLoS One 2010; 5:e12122. [PMID: 20711464 PMCID: PMC2920329 DOI: 10.1371/journal.pone.0012122] [Citation(s) in RCA: 108] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2010] [Accepted: 07/19/2010] [Indexed: 02/01/2023] Open
Abstract
The protein α-synuclein is involved in the pathogenesis of Parkinson's disease and other neurodegenerative disorders. Its toxic potential appears to be enhanced by increased protein expression, providing a compelling rationale for therapeutic strategies aimed at reducing neuronal α-synuclein burden. Here, feasibility and safety of α-synuclein suppression were evaluated by treating monkeys with small interfering RNA (siRNA) directed against α-synuclein. The siRNA molecule was chemically modified to prevent degradation by exo- and endonucleases and directly infused into the left substantia nigra. Results compared levels of α-synuclein mRNA and protein in the infused (left) vs. untreated (right) hemisphere and revealed a significant 40–50% suppression of α-synuclein expression. These findings could not be attributable to non-specific effects of siRNA infusion since treatment of a separate set of animals with luciferase-targeting siRNA produced no changes in α-synuclein. Infusion with α-synuclein siRNA, while lowering α-synuclein expression, had no overt adverse consequences. In particular, it did not cause tissue inflammation and did not change (i) the number and phenotype of nigral dopaminergic neurons, and (ii) the concentrations of striatal dopamine and its metabolites. The data represent the first evidence of successful anti-α-synuclein intervention in the primate substantia nigra and support further development of RNA interference-based therapeutics.
Collapse
Affiliation(s)
- Alison L. McCormack
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
- SRI International, Menlo Park, California, United States of America
| | - Sally K. Mak
- The Parkinson's Institute, Sunnyvale, California, United States of America
| | | | - David Bumcrot
- Alnylam Pharmaceuticals, Cambridge, Massachusetts, United States of America
| | - Matthew J. Farrer
- Mayo Clinic College of Medicine, Jacksonville, Florida, United States of America
| | - Donato A. Di Monte
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
- SRI International, Menlo Park, California, United States of America
- * E-mail:
| |
Collapse
|
276
|
Abstract
Parkinson's disease (PD) is a progressive neurodegenerative disorder that is characterized by the degeneration of dopamine (DA) and non-DA neurons, the almost uniform presence of Lewy bodies, and motor deficits. Although the majority of PD is sporadic, specific genetic defects in rare familial cases have provided unique insights into the pathogenesis of PD. Through the creation of animal and cellular models of mutations in LRRK2 and alpha-synuclein, which are linked to autosomal-dominant PD, and mutations in parkin, DJ-1, and PINK1, which are responsible for autosomal-recessive PD, insight into the molecular mechanisms of this disorder are leading to new ideas about the pathogenesis of PD. In this review, we discuss the animal models for these genetic causes of PD, their limitations, and value. Moreover, we discuss future directions and potential strategies for optimization of the genetic models.
Collapse
Affiliation(s)
- Ted M Dawson
- Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
| | | | | |
Collapse
|
277
|
Huang JZ, Chen YZ, Su M, Zheng HF, Yang YP, Chen J, Liu CF. dl-3-n-Butylphthalide prevents oxidative damage and reduces mitochondrial dysfunction in an MPP+-induced cellular model of Parkinson's disease. Neurosci Lett 2010; 475:89-94. [DOI: 10.1016/j.neulet.2010.03.053] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2010] [Revised: 03/03/2010] [Accepted: 03/22/2010] [Indexed: 12/22/2022]
|
278
|
Wang MS, Boddapati S, Emadi S, Sierks MR. Curcumin reduces alpha-synuclein induced cytotoxicity in Parkinson's disease cell model. BMC Neurosci 2010; 11:57. [PMID: 20433710 PMCID: PMC2879277 DOI: 10.1186/1471-2202-11-57] [Citation(s) in RCA: 126] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2009] [Accepted: 04/30/2010] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Overexpression and abnormal accumulation of aggregated alpha-synuclein (alphaS) have been linked to Parkinson's disease (PD) and other synucleinopathies. alphaS can misfold and adopt a variety of morphologies but recent studies implicate oligomeric forms as the most cytotoxic species. Both genetic mutations and chronic exposure to neurotoxins increase alphaS aggregation and intracellular reactive oxygen species (ROS), leading to mitochondrial dysfunction and oxidative damage in PD cell models. RESULTS Here we show that curcumin can alleviate alphaS-induced toxicity, reduce ROS levels and protect cells against apoptosis. We also show that both intracellular overexpression of alphaS and extracellular addition of oligomeric alphaS increase ROS which induces apoptosis, suggesting that aggregated alphaS may induce similar toxic effects whether it is generated intra- or extracellulary. CONCLUSIONS Since curcumin is a natural food pigment that can cross the blood brain barrier and has widespread medicinal uses, it has potential therapeutic value for treating PD and other neurodegenerative disorders.
Collapse
Affiliation(s)
- Min S Wang
- Department of Chemical Engineering, Arizona State University, Tempe, AZ 85287-6006, USA
| | | | | | | |
Collapse
|
279
|
Suk JE, Lokappa SB, Ulmer TS. The clustering and spatial arrangement of beta-sheet sequence, but not order, govern alpha-synuclein fibrillogenesis. Biochemistry 2010; 49:1533-40. [PMID: 20121219 DOI: 10.1021/bi901753h] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The intrinsically unstructured protein alpha-synuclein (aS) is prone to misfold into cytotoxic beta-sheet-rich oligomers and amyloid fibrils that underlie the pathogenesis of Lewy body diseases such as Parkinson's disease. An important, recognized fibrillogenesis parameter is amino acid content, whereas the influence of amino acid sequence distribution is not as well understood. The fibril core of aS encompasses five regions of high beta-sheet propensity, termed beta1-beta5. Using four aS variants with identical amino acid compositions but rearranged pseudorepeat motifs, we show that beta2-beta5 sequence clustering, but not order, is important for efficient fibrillogenesis. For molecular species progressing toward the fibrillar state, order invariably increases; i.e., the spatial arrangement of sequence elements becomes restricted. By introducing disulfide bonds in a fibril structure-based manner, we demonstrated that a successful protofibril-to-fibril conversion is dependent upon the spatial arrangement of sequence elements of high beta-sheet propensity. Moreover, a disulfide-linked aS dimer is shown to fibrillize rapidly. We propose that a conformational search underlies the emergence of a fibrillar aS nucleus that is directed by gaps in sequence between beta-sheet regions and the accessible range of spatial beta-sheet arrangements in soluble, prefibrillar oligomers. On the basis of the universal cross-beta-sheet structure of amyloid fibrils, these principles are expected to apply to a wide range of amyloidogenic proteins.
Collapse
Affiliation(s)
- Jae-Eun Suk
- Department of Biochemistry and Molecular Biology and Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, 1501 San Pablo Street, Los Angeles, California 90033, USA
| | | | | |
Collapse
|
280
|
Schneider L, Zhang J. Lysosomal function in macromolecular homeostasis and bioenergetics in Parkinson's disease. Mol Neurodegener 2010; 5:14. [PMID: 20388210 PMCID: PMC2867960 DOI: 10.1186/1750-1326-5-14] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2010] [Accepted: 04/13/2010] [Indexed: 12/21/2022] Open
Abstract
The pathological changes occurring in Parkinson's and several other neurodegenerative diseases are complex and poorly understood, but all clearly involve protein aggregation. Also frequently appearing in neurodegeneration is mitochondrial dysfunction which may precede, coincide or follow protein aggregation. These observations led to the concept that protein aggregation and mitochondrial dysfunction either arise from the same etiological factors or are interactive. Understanding the mechanisms and regulation of processes that lead to protein aggregation or mitochondrial dysfunction may therefore contribute to the design of better therapeutics. Clearance of protein aggregates and dysfunctional organelles is dependent on macroautophagy which is the process through which aged or damaged proteins and organelles are first degraded by the lysosome and then recycled. The macroautophagy-lysosomal pathway is essential for maintaining protein and energy homeostasis. Not surprisingly, failure of the lysosomal system has been implicated in diseases that have features of protein aggregation and mitochondrial dysfunction. This review summarizes 3 major topics: 1) the current understanding of Parkinson's disease pathogenesis in terms of accumulation of damaged proteins and reduction of cellular bioenergetics; 2) evolving insights into lysosomal function and biogenesis and the accumulating evidence that lysosomal dysfunction may cause or exacerbate Parkinsonian pathology and finally 3) the possibility that enhancing lysosomal function may provide a disease modifying therapy.
Collapse
Affiliation(s)
- Lonnie Schneider
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL35294, USA.
| | | |
Collapse
|
281
|
Yakunin E, Moser A, Loeb V, Saada A, Faust P, Crane DI, Baes M, Sharon R. alpha-Synuclein abnormalities in mouse models of peroxisome biogenesis disorders. J Neurosci Res 2010; 88:866-76. [PMID: 19830841 DOI: 10.1002/jnr.22246] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
alpha-Synuclein (alphaS) is a presynaptic protein implicated in Parkinson's disease (PD). Growing evidence implicates mitochondrial dysfunction, oxidative stress, and alphaS-lipid interactions in the gradual accumulation of alphaS in pathogenic forms and its deposition in Lewy bodies, the pathological hallmark of PD and related synucleinopathies. The peroxisomal biogenesis disorders (PBD), with Zellweger syndrome serving as the prototype of this group, are characterized by malformed and functionally impaired peroxisomes. Here we utilized the PBD mouse models Pex2-/-, Pex5-/-, and Pex13-/- to study the potential effects of peroxisomal dysfunction on alphaS-related pathogenesis. We found increased alphaS oligomerization and phosphorylation and its increased deposition in cytoplasmic inclusions in these PBD mouse models. Furthermore, we show that alphaS abnormalities correlate with the altered lipid metabolism and, specifically, with accumulation of long chain, n-6 polyunsaturated fatty acids that occurs in the PBD models.
Collapse
Affiliation(s)
- Eugenia Yakunin
- Department of Biochemistry and Molecular Biology, The Institute for Medical Research-Israel Canada, Hebrew University, Jerusalem, Israel
| | | | | | | | | | | | | | | |
Collapse
|
282
|
Cao P, Yuan Y, Pehek EA, Moise AR, Huang Y, Palczewski K, Feng Z. Alpha-synuclein disrupted dopamine homeostasis leads to dopaminergic neuron degeneration in Caenorhabditis elegans. PLoS One 2010; 5:e9312. [PMID: 20174477 PMCID: PMC2824852 DOI: 10.1371/journal.pone.0009312] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2009] [Accepted: 01/28/2010] [Indexed: 12/01/2022] Open
Abstract
Disruption of dopamine homeostasis may lead to dopaminergic neuron degeneration, a proposed explanation for the specific vulnerability of dopaminergic neurons in Parkinson's disease. While expression of human α-synuclein in C. elegans results in dopaminergic neuron degeneration, the effects of α-synuclein on dopamine homeostasis and its contribution to dopaminergic neuron degeneration in C. elegans have not been reported. Here, we examined the effects of α-synuclein overexpression on worm dopamine homeostasis. We found that α-synuclein expression results in upregulation of dopamine synthesis and content, and redistribution of dopaminergic synaptic vesicles, which significantly contribute to dopaminergic neuron degeneration. These results provide in vivo evidence supporting a critical role for dopamine homeostasis in supporting dopaminergic neuron integrity.
Collapse
Affiliation(s)
- Pengxiu Cao
- Department of Pharmacology, School of Medicine, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Yiyuan Yuan
- Department of Pharmacology, School of Medicine, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Elizabeth A. Pehek
- Departments of Psychiatry and Neurosciences, School of Medicine, Case Western Reserve University, Cleveland, Ohio, United States of America
- Department of Veterans Affairs, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, Ohio, United States of America
| | - Alex R. Moise
- Department of Pharmacology, School of Medicine, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Ying Huang
- Department of Pharmacology, School of Medicine, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Krzysztof Palczewski
- Department of Pharmacology, School of Medicine, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Zhaoyang Feng
- Department of Pharmacology, School of Medicine, Case Western Reserve University, Cleveland, Ohio, United States of America
- Department of Physiology, College of Medicine, Xi'an Jiaotong University, Xi'an, Shaanxi, China
- * E-mail:
| |
Collapse
|
283
|
Pérez-Sánchez F, Milán M, Buendía P, Cano-Jaimez M, Ambrosio S, Rosenthal A, Fariñas I. Prosurvival effect of human wild-type alpha-synuclein on MPTP-induced toxicity to central but not peripheral catecholaminergic neurons isolated from transgenic mice. Neuroscience 2010; 167:261-76. [PMID: 20156526 DOI: 10.1016/j.neuroscience.2010.02.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2009] [Revised: 02/01/2010] [Accepted: 02/08/2010] [Indexed: 12/15/2022]
Abstract
In the present work we report the generation of a new line of alpha-synuclein (alpha-SYN) transgenic mice in which the human wild-type alpha-SYN cDNA is expressed under the control of a tyrosine hydroxylase (TH) promoter. We provide evidence that the ectopic protein is found in TH expressing neurons of both central and peripheral nervous systems. The transgene is expressed very early in development coinciding with the activity of the TH promoter and in the adult brain the human protein distributes normally to the nerve endings and cell bodies of dopaminergic nigral neurons without any evidence of abnormal aggregation. Our results indicate that expression of human wild-type alpha-SYN does not affect normal development or maintenance of TH immunoreactive nigral neurons, striatal dopamine content, or locomotor activity. Systemic administration of the parkinsonian neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) induces a loss of TH immunoreactive nigral neurons and terminals and of dopamine levels to the same degree in both transgenic and non-transgenic adult mice. Intoxication also results in a similar loss of cardiac noradrenaline in both genotypes. Surprisingly, cultured transgenic ventral mesencephalic fetal dopaminergic neurons exhibit complete resistance to cell death induced by 1-methyl-4-phenylpyridinium ion (MPP(+)) intoxication, without changes in dopamine transporter (DAT) surface levels. Interestingly, this protection is not observed in other populations of catecholaminergic neurons such as peripheral sympathetic neurons, despite their high sensitivity to MPP(+)in vitro.
Collapse
Affiliation(s)
- F Pérez-Sánchez
- Departament de Biologia cellular and Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Universitat de València, 46100 Burjassot, València, Spain.
| | | | | | | | | | | | | |
Collapse
|
284
|
Waxman EA, Giasson BI. A novel, high-efficiency cellular model of fibrillar alpha-synuclein inclusions and the examination of mutations that inhibit amyloid formation. J Neurochem 2010; 113:374-88. [PMID: 20132485 DOI: 10.1111/j.1471-4159.2010.06592.x] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Intracytoplasmic alpha-synuclein (alpha-syn) amyloidogenic inclusions are a major pathological feature of Parkinson's disease, dementia with Lewy body disease and multiple systems atrophy. The mechanisms involved in the formation and inhibition of these aggregates are areas of intense investigation. The present study characterizes a novel cellular model for the study of alpha-syn aggregation, incorporating nucleation-dependent aggregation and a new function for calcium phosphate precipitation. Cultured cells were readily induced to develop large, cytoplasmic alpha-syn filamentous aggregates that were hyperphosphorylated, often ubiquitinated and thioflavin positive. These cellular aggregates formed in the majority of transfected cells and recruited approximately half of endogenously expressed alpha-syn. Using this system, we examined single-point mutations that inhibit alpha-syn amyloid formation in vitro. Three mutations (V66P, T72P and T75P) significantly hindered alpha-syn aggregation in this cell model. The T75P mutant, which could abrogate amyloid formation of wild-type alpha-syn in vitro, did not prevent wild-type alpha-syn cellular aggregates. These studies suggest that the propensity of alpha-syn to form cellular aggregates may be more pronounced than in isolated in vitro studies. This novel high-efficiency cellular model of alpha-syn aggregation is a valuable system that may be used to further understand alpha-syn aggregation and allow for the generation of future therapeutics.
Collapse
Affiliation(s)
- Elisa A Waxman
- Department of Pharmacology, University of Pennsylvania, Philadelphia, PA 19104-6084, USA
| | | |
Collapse
|
285
|
Vulnerability of peripheral catecholaminergic neurons to MPTP is not regulated by alpha-synuclein. Neurobiol Dis 2010; 38:92-103. [PMID: 20079841 DOI: 10.1016/j.nbd.2010.01.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2009] [Revised: 12/19/2009] [Accepted: 01/07/2010] [Indexed: 12/21/2022] Open
Abstract
Although generally considered a prototypical movement disorder, Parkinson's disease is commonly associated with a broad-spectrum of non-motor symptoms, including autonomic dysfunctions caused by significant alterations in catecholaminergic neurons of the peripheral sympathetic nervous system. Here we present evidence that alpha-synuclein is highly expressed by sympathetic ganglion neurons throughout embryonic and postnatal life and that it is found in tyrosine hydroxylase-positive sympathetic fibers innervating the heart of adult mice. However, mice deficient in alpha-synuclein do not exhibit any apparent alterations in sympathetic development. Sympathetic neurons isolated from mouse embryos and early postnatal mice are sensitive to the parkinsonian drug MPTP/MPP(+) and intoxication requires entry of the neurotoxin through the noradrenaline transporter. Furthermore, recovery of noradrenaline from cardiac sympathetic fibers is reduced in adult mice treated with MPTP systemically. However, MPP(+)-induced sympathetic neuron loss in vitro or MPTP-induced cardiac noradrenaline depletion in vivo is not modified in mice lacking alpha-synuclein. This is in clear contrast with the observation that dopaminergic neurons of the central nervous system are significantly less vulnerable to MPTP/MPP(+) in the absence of alpha-synuclein, suggesting different actions of this molecule in central and peripheral catecholaminergic neurons.
Collapse
|
286
|
Loeb V, Yakunin E, Saada A, Sharon R. The transgenic overexpression of alpha-synuclein and not its related pathology associates with complex I inhibition. J Biol Chem 2010; 285:7334-43. [PMID: 20053987 DOI: 10.1074/jbc.m109.061051] [Citation(s) in RCA: 91] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Alpha-synuclein (alphaS) is a protein involved in the cytopathology and genetics of Parkinson disease and is thought to affect mitochondrial complex I activity. Previous studies have shown that mitochondrial toxins and specifically inhibitors of complex I activity enhance alphaS pathogenesis. Here we show that alphaS overexpression specifically inhibits complex I activity in dopaminergic cells and in A53T alphaS transgenic mouse brains. Importantly, our results indicate that the inhibitory effect on complex I activity is not associated with alphaS-related pathology. Specifically, complex I activity measured in purified mitochondria from A53T alphaS transgenic mouse brains was not affected by mouse age; Parkinson disease-like symptoms; levels of alphaS soluble oligomers; levels of insoluble, lipid-associated alphaS; or alphaS intraneuronal depositions in vivo. Likewise, no correlation was found between complex I activity and polyunsaturated fatty acid-induced alphaS depositions in Lewy body-like inclusions in cultured dopaminergic cells. We further show that the effect of alphaS on complex I activity is not due to altered mitochondrial protein levels or affected complex I assembly. Based on the results herein, we suggest that alphaS expression negatively regulates complex I activity as part of its normal, physiological role.
Collapse
Affiliation(s)
- Virginie Loeb
- Department of Biochemistry and Molecular Biology, The Institute for Medical Research, Israel-Canada, Hebrew University, Jerusalem 91120, Israel
| | | | | | | |
Collapse
|
287
|
Hettiarachchi NT, Parker A, Dallas ML, Pennington K, Hung CC, Pearson HA, Boyle JP, Robinson P, Peers C. α-Synuclein modulation of Ca2+signaling in human neuroblastoma (SH-SY5Y) cells. J Neurochem 2009; 111:1192-201. [DOI: 10.1111/j.1471-4159.2009.06411.x] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
|
288
|
Chen L, Periquet M, Wang X, Negro A, McLean PJ, Hyman BT, Feany MB. Tyrosine and serine phosphorylation of alpha-synuclein have opposing effects on neurotoxicity and soluble oligomer formation. J Clin Invest 2009; 119:3257-3265. [PMID: 19855133 PMCID: PMC2769182 DOI: 10.1172/jci39088] [Citation(s) in RCA: 108] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2009] [Accepted: 08/26/2009] [Indexed: 09/27/2023] Open
Abstract
Mutations in the neuronal protein alpha-synuclein cause familial Parkinson disease. Phosphorylation of alpha-synuclein at serine 129 is prominent in Parkinson disease and influences alpha-synuclein neurotoxicity. Here we report that alpha-synuclein is also phosphorylated at tyrosine 125 in transgenic Drosophila expressing wild-type human alpha-synuclein and that this tyrosine phosphorylation protects from alpha-synuclein neurotoxicity in a Drosophila model of Parkinson disease. Western blot analysis of fly brain homogenates showed that levels of soluble oligomeric species of alpha-synuclein were increased by phosphorylation at serine 129 and decreased by tyrosine 125 phosphorylation. Tyrosine 125 phosphorylation diminished during the normal aging process in both humans and flies. Notably, cortical tissue from patients with the Parkinson disease-related synucleinopathy dementia with Lewy bodies showed less phosphorylation at tyrosine 125. Our findings suggest that alpha-synuclein neurotoxicity in Parkinson disease and related synucleinopathies may result from an imbalance between the detrimental, oligomer-promoting effect of serine 129 phosphorylation and a neuroprotective action of tyrosine 125 phosphorylation that inhibits toxic oligomer formation.
Collapse
Affiliation(s)
- Li Chen
- Department of Pathology and
Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts, USA.
Department of Biochemistry, Università di Padova, Padua, Italy.
Department of Neurology, Massachusetts General Hospital, Charlestown, Massachusetts, USA
| | - Magali Periquet
- Department of Pathology and
Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts, USA.
Department of Biochemistry, Università di Padova, Padua, Italy.
Department of Neurology, Massachusetts General Hospital, Charlestown, Massachusetts, USA
| | - Xu Wang
- Department of Pathology and
Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts, USA.
Department of Biochemistry, Università di Padova, Padua, Italy.
Department of Neurology, Massachusetts General Hospital, Charlestown, Massachusetts, USA
| | - Alessandro Negro
- Department of Pathology and
Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts, USA.
Department of Biochemistry, Università di Padova, Padua, Italy.
Department of Neurology, Massachusetts General Hospital, Charlestown, Massachusetts, USA
| | - Pamela J. McLean
- Department of Pathology and
Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts, USA.
Department of Biochemistry, Università di Padova, Padua, Italy.
Department of Neurology, Massachusetts General Hospital, Charlestown, Massachusetts, USA
| | - Bradley T. Hyman
- Department of Pathology and
Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts, USA.
Department of Biochemistry, Università di Padova, Padua, Italy.
Department of Neurology, Massachusetts General Hospital, Charlestown, Massachusetts, USA
| | - Mel B. Feany
- Department of Pathology and
Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts, USA.
Department of Biochemistry, Università di Padova, Padua, Italy.
Department of Neurology, Massachusetts General Hospital, Charlestown, Massachusetts, USA
| |
Collapse
|
289
|
Forebrain overexpression of alpha-synuclein leads to early postnatal hippocampal neuron loss and synaptic disruption. Exp Neurol 2009; 221:86-97. [PMID: 19833127 DOI: 10.1016/j.expneurol.2009.10.005] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2009] [Revised: 10/01/2009] [Accepted: 10/03/2009] [Indexed: 11/22/2022]
Abstract
Transgenic (Tg) mouse models of Parkinson's disease (PD) generated to date have primarily been designed to overexpress human alpha-synuclein (alpha-syn) to recapitulate PD-like motor impairments as well as PD-like nigrostriatal degeneration and alpha-syn pathology. However, cognitive impairments and cortical alpha-syn pathology are also common in PD patients. To model these features of PD, we created forebrain-specific conditional Tg mice that overexpress human wild type (WT) or A53T mutant alpha-syn. Here we show that both WT and A53T mutant alpha-syn lead to massive degeneration of postmitotic neurons in the hippocampal dentate gyrus (DG) during postnatal development, with hippocampal synapse loss as evidenced by reduced levels of pre- and postsynaptic markers. However, when mutant and WT alpha-syn expression was repressed until the Tg mice were mature postnatally and then induced for several months, no hippocampal neuron loss was observed. These data imply that developing neurons are more vulnerable to degenerate than mature neurons as a consequence of forebrain WT and mutant alpha-syn overexpression.
Collapse
|
290
|
Hatano T, Kubo SI, Sato S, Hattori N. Pathogenesis of familial Parkinson's disease: new insights based on monogenic forms of Parkinson's disease. J Neurochem 2009; 111:1075-93. [PMID: 19780902 DOI: 10.1111/j.1471-4159.2009.06403.x] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Parkinson's disease (PD) is one of the most common movement disorders caused by the loss of dopaminergic neuronal cells. The molecular mechanisms underlying neuronal degeneration in PD remain unknown; however, it is now clear that genetic factors contribute to the pathogenesis of this disease. Approximately, 5% of patients with clinical features of PD have clear familial etiology, which show a classical recessive or dominant Mendelian mode of inheritance. Over the decade, more than 15 loci and 11 causative genes have been identified so far and many studies shed light on their implication in not only monogenic but also sporadic form of PD. Recent studies revealed that PD-associated genes play important roles in cellular functions, such as mitochondrial functions, ubiquitin-proteasomal system, autophagy-lysosomal pathway and membrane trafficking. Furthermore, the proteins encoded by PD-associated genes can interact with each other and such gene products may share a common pathway that leads to nigral degeneration. However, their precise roles in the disease and their normal functions remain poorly understood. In this study, we review recent progress in knowledge about the genes associated with familial PD.
Collapse
Affiliation(s)
- Taku Hatano
- Department of Neurology, Juntendo University, School of Medicine, Hongo Bunkyo Tokyo, Japan
| | | | | | | |
Collapse
|
291
|
Expression of alpha-synuclein is increased in the hippocampus of rats with high levels of innate anxiety. Mol Psychiatry 2009; 14:894-905. [PMID: 18427558 DOI: 10.1038/mp.2008.43] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
A genomic region neighboring the alpha-synuclein gene, on rat chromosome 4, has been associated with anxiety- and alcohol-related behaviors in different rat strains. In this study, we have investigated potential molecular and physiological links between alpha-synuclein and the behavioral differences observed between Lewis (LEW) and Spontaneously Hypertensive (SHR) inbred rats, a genetic model of anxiety. As expected, LEW rats appeared more fearful than SHR rats in three anxiety models: open field, elevated plus maze and light/dark box. Moreover, LEW rats displayed a higher preference for alcohol and consumed higher quantities of alcohol than SHR rats. alpha-Synuclein mRNA and protein concentrations were higher in the hippocampus, but not the hypothalamus of LEW rats. This result inversely correlated with differences in dopamine turnover in the hippocampus of LEW and SHR rats, supporting the hypothesis that alpha-synuclein is important in the downregulation of dopamine neurotransmission. A novel single nucleotide polymorphism was identified in the 3'-untranslated region (3'-UTR) of the alpha-synuclein cDNA between these two rat strains. Plasmid constructs based on the LEW 3'-UTR sequence displayed increased expression of a reporter gene in transiently transfected PC12 cells, in accordance with in-vivo findings, suggesting that this nucleotide exchange might participate in the differential expression of alpha-synuclein between LEW and SHR rats. These results are consistent with a novel role for alpha-synuclein in modulating rat anxiety-like behaviors, possibly through dopaminergic mechanisms. Since the behavioral and genetic differences between these two strains are the product of independent evolutionary histories, the possibility that polymorphisms in the alpha-synuclein gene may be associated with vulnerability to anxiety-related disorders in humans requires further investigation.
Collapse
|
292
|
Kritzer JA, Hamamichi S, McCaffery JM, Santagata S, Naumann TA, Caldwell KA, Caldwell GA, Lindquist S. Rapid selection of cyclic peptides that reduce alpha-synuclein toxicity in yeast and animal models. Nat Chem Biol 2009; 5:655-63. [PMID: 19597508 PMCID: PMC2729362 DOI: 10.1038/nchembio.193] [Citation(s) in RCA: 109] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2009] [Accepted: 05/08/2009] [Indexed: 11/25/2022]
Abstract
Phage display has demonstrated the utility of cyclic peptides as general protein ligands but cannot access proteins inside eukaryotic cells. Expanding a new chemical genetics tool, we describe the first expressed library of head-to-tail cyclic peptides in yeast (Saccharomyces cerevisiae). We applied the library to selections in a yeast model of alpha-synuclein toxicity that recapitulates much of the cellular pathology of Parkinson's disease. From a pool of 5 million transformants, we isolated two related cyclic peptide constructs that specifically reduced the toxicity of human alpha-synuclein. These expressed cyclic peptide constructs also prevented dopaminergic neuron loss in an established Caenorhabditis elegans Parkinson's model. This work highlights the speed and efficiency of using libraries of expressed cyclic peptides for forward chemical genetics in cellular models of human disease.
Collapse
Affiliation(s)
- Joshua A. Kritzer
- Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge MA 02142
| | - Shusei Hamamichi
- Department of Biological Sciences, University of Alabama, Tuscaloosa, AL 35487
| | - J. Michael McCaffery
- Integrated Imaging Center and Department of Biology, Johns Hopkins University, Baltimore, MD 21218
| | - Sandro Santagata
- Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge MA 02142
- Department of Pathology, Brigham and Women's Hospital, Boston, MA, USA, and Harvard Medical School, Boston, Massachusetts, USA
| | - Todd A. Naumann
- Department of Chemistry, The Pennsylvania State University, University Park, PA 16802
| | - Kim A. Caldwell
- Department of Biological Sciences, University of Alabama, Tuscaloosa, AL 35487
| | - Guy A. Caldwell
- Department of Biological Sciences, University of Alabama, Tuscaloosa, AL 35487
| | - Susan Lindquist
- Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge MA 02142
- Howard Hughes Medical Institute, Department of Biology, Massachusetts Institute of Technology, Cambridge MA 02139
| |
Collapse
|
293
|
Waxman EA, Covy JP, Bukh I, Li X, Dawson TM, Giasson BI. Leucine-rich repeat kinase 2 expression leads to aggresome formation that is not associated with alpha-synuclein inclusions. J Neuropathol Exp Neurol 2009; 68:785-96. [PMID: 19535993 DOI: 10.1097/nen.0b013e3181aaf4fd] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Mutations in leucine-rich repeat kinase-2 (LRRK2) are the most common known cause of Parkinson disease, but how this protein results in the pathobiology of Parkinson disease is unknown. Moreover, there is variability in pathology among cases, and alpha-synuclein (alpha-syn) neuronal inclusions are often present, but whether LRRK2 is present in these pathological inclusions is controversial. This study characterizes novel LRRK2 antibodies, some of which preferentially recognize an aggregated form of LRRK2, as observed in cell culture models. Large perinuclear aggregates containing LRRK2 were promoted by proteasome inhibition and prevented by microtubule polymerization inhibition. Furthermore, they were vimentin- and gamma-tubulin- but not lamp1-immunoreactive, suggesting that these structures fit the definition of aggresomes. Inhibition of heat shock protein 90 led to the degradation of only the soluble/cytosolic pool of LRRK2, suggesting that the aggresomes formed independent of the stability provided by the heat shock protein 90. Although these novel anti-LRRK2 antibodies identified aggregates in model cell systems, they did not immunostain pathological inclusions in human brains. Furthermore, coexpression of LRRK2 and alpha-syn did not recruit alpha-syn into aggresomes in cultured cells, even in the presence of proteasome inhibition. Thus, although LRRK2 is a model system for aggresome formation, LRRK2 is not present in alpha-syn pathological inclusions.
Collapse
Affiliation(s)
- Elisa A Waxman
- Department of Pharmacology, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6084, USA
| | | | | | | | | | | |
Collapse
|
294
|
Ovádi J, Orosz F. An unstructured protein with destructive potential: TPPP/p25 in neurodegeneration. Bioessays 2009; 31:676-86. [DOI: 10.1002/bies.200900008] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
|
295
|
Lessing D, Bonini NM. Maintaining the brain: insight into human neurodegeneration from Drosophila melanogaster mutants. Nat Rev Genet 2009; 10:359-70. [PMID: 19434080 PMCID: PMC2820605 DOI: 10.1038/nrg2563] [Citation(s) in RCA: 133] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The fruitfly Drosophila melanogaster has enabled significant advances in neurodegenerative disease research, notably in the identification of genes that are required to maintain the structural integrity of the brain, defined by recessive mutations that cause adult onset neurodegeneration. Here, we survey these genes in the fly and classify them according to five key cell biological processes. Over half of these genes have counterparts in mice or humans that are also associated with neurodegeneration. Fly genetics continues to be instrumental in the analysis of degenerative disease, with notable recent advances in our understanding of several inherited disorders, Parkinson's disease, and the central role of mitochondria in neuronal maintenance.
Collapse
Affiliation(s)
- Derek Lessing
- Howard Hughes Medical Institute, University of Pennsylvania, Philadelphia, PA 19104
| | - Nancy M. Bonini
- Howard Hughes Medical Institute, University of Pennsylvania, Philadelphia, PA 19104
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19104
| |
Collapse
|
296
|
Effect of pseudorepeat rearrangement on alpha-synuclein misfolding, vesicle binding, and micelle binding. J Mol Biol 2009; 390:516-29. [PMID: 19481090 DOI: 10.1016/j.jmb.2009.05.058] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2009] [Revised: 05/14/2009] [Accepted: 05/18/2009] [Indexed: 01/13/2023]
Abstract
The pathological and physiological hallmarks of the protein alpha-synuclein (aS) are its misfolding into cytotoxic aggregates and its binding to synaptic vesicles, respectively. Both events are mediated by seven 11-residue amphiphilic pseudorepeats and, most generally, involve a transition from intrinsically unstructured conformations to structured conformations. Based on aS interactions with aggregation-inhibiting small molecules, an aS variant termed shuffled alpha-synuclein (SaS), wherein the first six pseudorepeats had been rearranged, was introduced. Here, the effects of this rearrangement on misfolding, vesicle binding, and micelle binding are examined in reference to aS and beta-synuclein to study the sequence characteristics underlying these processes. Fibrillization correlates with the distinct clustering of residues with high beta-sheet propensities, while vesicle affinities depend on the mode of pseudorepeat interchange and loss. In the presence of micelles, the pseudorepeat region of SaS adopts an essentially continuous helix, whereas aS and beta-synuclein encounter a distinct helix break, indicating that a more homogeneous distribution of surfactant affinities in SaS prevented the formation of an extensive helix break in the micelle-bound state. By demonstrating the importance of the distribution of beta-sheet propensities and by revealing inhomogeneous aS surfactant affinities, the present study provides novel insights into two central themes of synuclein biology.
Collapse
|
297
|
Marambaud P, Dreses-Werringloer U, Vingtdeux V. Calcium signaling in neurodegeneration. Mol Neurodegener 2009; 4:20. [PMID: 19419557 PMCID: PMC2689218 DOI: 10.1186/1750-1326-4-20] [Citation(s) in RCA: 232] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2009] [Accepted: 05/06/2009] [Indexed: 12/16/2022] Open
Abstract
Calcium is a key signaling ion involved in many different intracellular and extracellular processes ranging from synaptic activity to cell-cell communication and adhesion. The exact definition at the molecular level of the versatility of this ion has made overwhelming progress in the past several years and has been extensively reviewed. In the brain, calcium is fundamental in the control of synaptic activity and memory formation, a process that leads to the activation of specific calcium-dependent signal transduction pathways and implicates key protein effectors, such as CaMKs, MAPK/ERKs, and CREB. Properly controlled homeostasis of calcium signaling not only supports normal brain physiology but also maintains neuronal integrity and long-term cell survival. Emerging knowledge indicates that calcium homeostasis is not only critical for cell physiology and health, but also, when deregulated, can lead to neurodegeneration via complex and diverse mechanisms involved in selective neuronal impairments and death. The identification of several modulators of calcium homeostasis, such as presenilins and CALHM1, as potential factors involved in the pathogenesis of Alzheimer's disease, provides strong support for a role of calcium in neurodegeneration. These observations represent an important step towards understanding the molecular mechanisms of calcium signaling disturbances observed in different brain diseases such as Alzheimer's, Parkinson's, and Huntington's diseases.
Collapse
Affiliation(s)
- Philippe Marambaud
- Litwin-Zucker Research Center for the Study of Alzheimer's Disease, The Feinstein Institute for Medical Research, North Shore-LIJ, Manhasset, New York 11030, USA.
| | | | | |
Collapse
|
298
|
Bacterial artificial chromosome transgenic mice expressing a truncated mutant parkin exhibit age-dependent hypokinetic motor deficits, dopaminergic neuron degeneration, and accumulation of proteinase K-resistant alpha-synuclein. J Neurosci 2009; 29:1962-76. [PMID: 19228951 DOI: 10.1523/jneurosci.5351-08.2009] [Citation(s) in RCA: 129] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Recessive mutations in parkin are the most common cause of familial early-onset Parkinson's disease (PD). Recent studies suggest that certain parkin mutants may exert dominant toxic effects to cultured cells and such dominant toxicity can lead to progressive dopaminergic (DA) neuron degeneration in Drosophila. To explore whether mutant parkin could exert similar pathogenic effects to mammalian DA neurons in vivo, we developed a BAC (bacterial artificial chromosome) transgenic mouse model expressing a C-terminal truncated human mutant parkin (Parkin-Q311X) in DA neurons driven by a dopamine transporter promoter. Parkin-Q311X mice exhibit multiple late-onset and progressive hypokinetic motor deficits. Stereological analyses reveal that the mutant mice develop age-dependent DA neuron degeneration in substantia nigra accompanied by a significant loss of DA neuron terminals in the striatum. Neurochemical analyses reveal a significant reduction of the striatal dopamine level in mutant mice, which is significantly correlated with their hypokinetic motor deficits. Finally, mutant Parkin-Q311X mice, but not wild-type controls, exhibit age-dependent accumulation of proteinase K-resistant endogenous alpha-synuclein in substantia nigra and colocalized with 3-nitrotyrosine, a marker for oxidative protein damage. Hence, our study provides the first mammalian genetic evidence that dominant toxicity of a parkin mutant is sufficient to elicit age-dependent hypokinetic motor deficits and DA neuron loss in vivo, and uncovers a causal relationship between dominant parkin toxicity and progressive alpha-synuclein accumulation in DA neurons. Our study underscores the need to further explore the putative link between parkin dominant toxicity and PD.
Collapse
|
299
|
Rospigliosi CC, McClendon S, Schmid AW, Ramlall TF, Barré P, Lashuel HA, Eliezer D. E46K Parkinson's-linked mutation enhances C-terminal-to-N-terminal contacts in alpha-synuclein. J Mol Biol 2009; 388:1022-32. [PMID: 19345692 DOI: 10.1016/j.jmb.2009.03.065] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2009] [Revised: 03/21/2009] [Accepted: 03/28/2009] [Indexed: 10/20/2022]
Abstract
Parkinson's disease (PD) is associated with the deposition of fibrillar aggregates of the protein alpha-synuclein (alphaS) in neurons. Intramolecular contacts between the acidic C-terminal tail of alphaS and its N-terminal region have been proposed to regulate alphaS aggregation, and two originally described PD mutations, A30P and A53T, reportedly reduce such contacts. We find that the most recently discovered PD-linked alphaS mutation E46K, which also accelerates the aggregation of the protein, does not interfere with C-terminal-to-N-terminal contacts and instead enhances such contacts. Furthermore, we do not observe a substantial reduction in such contacts in the two previously characterized mutants. Our results suggest that C-terminal-to-N-terminal contacts in alphaS are not strongly protective against aggregation, and that the dominant mechanism by which PD-linked mutations facilitate alphaS aggregation may be altering the physicochemical properties of the protein such as net charge (E46K) and secondary structure propensity (A30P and A53T).
Collapse
Affiliation(s)
- Carla C Rospigliosi
- Department of Biochemistry and Program in Structural Biology, Weill Cornell Medical College, New York, NY 10065, USA
| | | | | | | | | | | | | |
Collapse
|
300
|
Abstract
Parkinson's disease (PD) is a common neurodegenerative disease characterized by the loss of dopaminergic neurons leading to bradykinesia, rest tremor and rigidity. Although the majority of PD is sporadic, rare genetic causes of PD are providing tremendous insight into the pathogenesis of PD. Here I shortly review the major genes implicated in autosomal dominant and autosomal recessive PD. Understanding how mutations in these PD associated genes holds particular promise for development of new therapies to treat PD.
Collapse
Affiliation(s)
- Ted M Dawson
- Institute for Cell Engineering, Departments of Neurology and Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
| |
Collapse
|