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Nunes ACL, Carmo M, Behrenswerth A, Canas PM, Agostinho P, Cunha RA. Adenosine A 2A Receptor Blockade Provides More Effective Benefits at the Onset Rather than after Overt Neurodegeneration in a Rat Model of Parkinson's Disease. Int J Mol Sci 2024; 25:4903. [PMID: 38732120 PMCID: PMC11084368 DOI: 10.3390/ijms25094903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2024] [Revised: 04/24/2024] [Accepted: 04/26/2024] [Indexed: 05/13/2024] Open
Abstract
Adenosine A2A receptor (A2AR) antagonists are the leading nondopaminergic therapy to manage Parkinson's disease (PD) since they afford both motor benefits and neuroprotection. PD begins with a synaptic dysfunction and damage in the striatum evolving to an overt neuronal damage of dopaminergic neurons in the substantia nigra. We tested if A2AR antagonists are equally effective in controlling these two degenerative processes. We used a slow intracerebroventricular infusion of the toxin MPP+ in male rats for 15 days, which caused an initial loss of synaptic markers in the striatum within 10 days, followed by a neuronal loss in the substantia nigra within 30 days. Interestingly, the initial loss of striatal nerve terminals involved a loss of both dopaminergic and glutamatergic synaptic markers, while GABAergic markers were preserved. The daily administration of the A2AR antagonist SCH58261 (0.1 mg/kg, i.p.) in the first 10 days after MPP+ infusion markedly attenuated both the initial loss of striatal synaptic markers and the subsequent loss of nigra dopaminergic neurons. Strikingly, the administration of SCH58261 (0.1 mg/kg, i.p. for 10 days) starting 20 days after MPP+ infusion was less efficacious to attenuate the loss of nigra dopaminergic neurons. This prominent A2AR-mediated control of synaptotoxicity was directly confirmed by showing that the MPTP-induced dysfunction (MTT assay) and damage (lactate dehydrogenase release assay) of striatal synaptosomes were prevented by 50 nM SCH58261. This suggests that A2AR antagonists may be more effective to counteract the onset rather than the evolution of PD pathology.
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Affiliation(s)
- Ana Carla L. Nunes
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal; (A.C.L.N.); (M.C.); (A.B.); (P.M.C.); (P.A.)
| | - Marta Carmo
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal; (A.C.L.N.); (M.C.); (A.B.); (P.M.C.); (P.A.)
| | - Andrea Behrenswerth
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal; (A.C.L.N.); (M.C.); (A.B.); (P.M.C.); (P.A.)
| | - Paula M. Canas
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal; (A.C.L.N.); (M.C.); (A.B.); (P.M.C.); (P.A.)
| | - Paula Agostinho
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal; (A.C.L.N.); (M.C.); (A.B.); (P.M.C.); (P.A.)
- Faculty of Medicine, University of Coimbra, 3004-504 Coimbra, Portugal
| | - Rodrigo A. Cunha
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal; (A.C.L.N.); (M.C.); (A.B.); (P.M.C.); (P.A.)
- Faculty of Medicine, University of Coimbra, 3004-504 Coimbra, Portugal
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2
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Yang S, Park JH, Lu HC. Axonal energy metabolism, and the effects in aging and neurodegenerative diseases. Mol Neurodegener 2023; 18:49. [PMID: 37475056 PMCID: PMC10357692 DOI: 10.1186/s13024-023-00634-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 06/08/2023] [Indexed: 07/22/2023] Open
Abstract
Human studies consistently identify bioenergetic maladaptations in brains upon aging and neurodegenerative disorders of aging (NDAs), such as Alzheimer's disease, Parkinson's disease, Huntington's disease, and Amyotrophic lateral sclerosis. Glucose is the major brain fuel and glucose hypometabolism has been observed in brain regions vulnerable to aging and NDAs. Many neurodegenerative susceptible regions are in the topological central hub of the brain connectome, linked by densely interconnected long-range axons. Axons, key components of the connectome, have high metabolic needs to support neurotransmission and other essential activities. Long-range axons are particularly vulnerable to injury, neurotoxin exposure, protein stress, lysosomal dysfunction, etc. Axonopathy is often an early sign of neurodegeneration. Recent studies ascribe axonal maintenance failures to local bioenergetic dysregulation. With this review, we aim to stimulate research in exploring metabolically oriented neuroprotection strategies to enhance or normalize bioenergetics in NDA models. Here we start by summarizing evidence from human patients and animal models to reveal the correlation between glucose hypometabolism and connectomic disintegration upon aging/NDAs. To encourage mechanistic investigations on how axonal bioenergetic dysregulation occurs during aging/NDAs, we first review the current literature on axonal bioenergetics in distinct axonal subdomains: axon initial segments, myelinated axonal segments, and axonal arbors harboring pre-synaptic boutons. In each subdomain, we focus on the organization, activity-dependent regulation of the bioenergetic system, and external glial support. Second, we review the mechanisms regulating axonal nicotinamide adenine dinucleotide (NAD+) homeostasis, an essential molecule for energy metabolism processes, including NAD+ biosynthetic, recycling, and consuming pathways. Third, we highlight the innate metabolic vulnerability of the brain connectome and discuss its perturbation during aging and NDAs. As axonal bioenergetic deficits are developing into NDAs, especially in asymptomatic phase, they are likely exaggerated further by impaired NAD+ homeostasis, the high energetic cost of neural network hyperactivity, and glial pathology. Future research in interrogating the causal relationship between metabolic vulnerability, axonopathy, amyloid/tau pathology, and cognitive decline will provide fundamental knowledge for developing therapeutic interventions.
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Affiliation(s)
- Sen Yang
- The Linda and Jack Gill Center for Biomolecular Sciences, Indiana University, Bloomington, IN, 47405, USA
- Department of Psychological and Brain Sciences, Indiana University, Bloomington, IN, 47405, USA
- Program in Neuroscience, Indiana University, Bloomington, IN, 47405, USA
| | - Jung Hyun Park
- The Linda and Jack Gill Center for Biomolecular Sciences, Indiana University, Bloomington, IN, 47405, USA
- Department of Psychological and Brain Sciences, Indiana University, Bloomington, IN, 47405, USA
- Program in Neuroscience, Indiana University, Bloomington, IN, 47405, USA
| | - Hui-Chen Lu
- The Linda and Jack Gill Center for Biomolecular Sciences, Indiana University, Bloomington, IN, 47405, USA.
- Department of Psychological and Brain Sciences, Indiana University, Bloomington, IN, 47405, USA.
- Program in Neuroscience, Indiana University, Bloomington, IN, 47405, USA.
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3
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Overmeyer C, Jorgensen K, Vohra BPS. The Translocase of the Outer Mitochondrial Membrane (TOM40) is required for mitochondrial dynamics and neuronal integrity in Dorsal Root Ganglion Neurons. Mol Cell Neurosci 2023; 125:103853. [PMID: 37100265 DOI: 10.1016/j.mcn.2023.103853] [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: 02/28/2023] [Revised: 04/04/2023] [Accepted: 04/12/2023] [Indexed: 04/28/2023] Open
Abstract
Polymorphisms and altered expression of the Translocase of the Outer Mitochondrial Membrane - 40 kD (Tom40) are observed in neurodegenerative disease subjects. We utilized in vitro cultured dorsal root ganglion (DRG) neurons to investigate the association of TOM40 depletion to neurodegeneration, and to unravel the mechanism of neurodegeneration induced by decreased levels of TOM40 protein. We provide evidence that severity of neurodegeneration induced in the TOM40 depleted neurons increases with the increase in the depletion of TOM40 and is exacerbated by an increase in the duration of TOM40 depletion. We also demonstrate that TOM40 depletion causes a surge in neuronal calcium levels, decreases mitochondrial motility, increases mitochondrial fission, and decreases neuronal ATP levels. We observed that alterations in the neuronal calcium homeostasis and mitochondrial dynamics precede BCL-xl and NMNAT1 dependent neurodegenerative pathways in the TOM40 depleted neurons. This data also suggests that manipulation of BCL-xl and NMNAT1 may be of therapeutic value in TOM40 associated neurodegenerative disorders.
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Affiliation(s)
| | - Kylie Jorgensen
- Department of Biology, William Jewell College Liberty, MO 64068
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4
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Meng L, Wang H, Zou T, Wang X, Chen H, Xie F, Li R. Attenuated brain white matter functional network interactions in Parkinson's disease. Hum Brain Mapp 2022; 43:4567-4579. [PMID: 35674466 PMCID: PMC9491278 DOI: 10.1002/hbm.25973] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 05/24/2022] [Accepted: 05/29/2022] [Indexed: 01/21/2023] Open
Abstract
Parkinson's disease (PD) is a neurodegenerative disorder characterized by extensive structural abnormalities in cortical and subcortical brain areas. However, an association between changes in the functional networks in brain white matter (BWM) and Parkinson's symptoms remains unclear. With confirming evidence that resting‐state functional magnetic resonance imaging (rs‐fMRI) of BWM signals can effectively describe neuronal activity, this study investigated the interactions among BWM functional networks in PD relative to healthy controls (HC). Sixty‐eight patients with PD and sixty‐three HC underwent rs‐fMRI. Twelve BWM functional networks were identified by K‐means clustering algorithm, which were further classified as deep, middle, and superficial layers. Network‐level interactions were examined via coefficient Granger causality analysis. Compared with the HC, the patients with PD displayed significantly weaker functional interaction strength within the BWM networks, particularly excitatory influences from the superficial to deep networks. The patients also showed significantly weaker inhibitory influences from the deep to superficial networks. Additionally, the sum of the absolutely positive/negative regression coefficients of the tri‐layered networks in the patients was lower relative to HC (p < .05, corrected for false discovery rate). Moreover, we found the functional interactions involving the deep BWM networks negatively correlated with part III of the Unified Parkinson's Disease Rating Scales and Hamilton Depression Scales. Taken together, we demonstrated attenuated BWM interactions in PD and these abnormalities were associated with clinical motor and nonmotor symptoms. These findings may aid understanding of the neuropathology of PD and its progression throughout the nervous system from the perspective of BWM function.
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Affiliation(s)
- Li Meng
- Department of Radiology, Xiangya Hospital, Central South University, Changsha, People's Republic of China.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Hongyu Wang
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Laboratory for Neuroinformation, High-Field Magnetic Resonance Brain Imaging Key Laboratory of Sichuan Province, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, People's Republic of China
| | - Ting Zou
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Laboratory for Neuroinformation, High-Field Magnetic Resonance Brain Imaging Key Laboratory of Sichuan Province, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, People's Republic of China
| | - Xuyang Wang
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Laboratory for Neuroinformation, High-Field Magnetic Resonance Brain Imaging Key Laboratory of Sichuan Province, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, People's Republic of China
| | - Huafu Chen
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Laboratory for Neuroinformation, High-Field Magnetic Resonance Brain Imaging Key Laboratory of Sichuan Province, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, People's Republic of China
| | - Fangfang Xie
- Department of Radiology, Xiangya Hospital, Central South University, Changsha, People's Republic of China.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Rong Li
- The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Laboratory for Neuroinformation, High-Field Magnetic Resonance Brain Imaging Key Laboratory of Sichuan Province, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, People's Republic of China
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5
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Yakhine-Diop SMS, Rodríguez-Arribas M, Canales-Cortés S, Martínez-Chacón G, Uribe-Carretero E, Blanco-Benítez M, Duque-González G, Paredes-Barquero M, Alegre-Cortés E, Climent V, Aiastui A, López de Munain A, Bravo-San Pedro JM, Niso-Santano M, Fuentes JM, González-Polo RA. The parkinsonian LRRK2 R1441G mutation shows macroautophagy-mitophagy dysregulation concomitant with endoplasmic reticulum stress. Cell Biol Toxicol 2021; 38:889-911. [PMID: 34060004 DOI: 10.1007/s10565-021-09617-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 05/12/2021] [Indexed: 12/15/2022]
Abstract
Autophagy is a mechanism responsible for the degradation of cellular components to maintain their homeostasis. However, autophagy is commonly altered and compromised in several diseases, including neurodegenerative disorders. Parkinson's disease (PD) can be considered a multifactorial disease because environmental factors, genetic factors, and aging are involved. Several genes are involved in PD pathology, among which the LRRK2 gene and its mutations, inherited in an autosomal dominant manner, are responsible for most genetic PD cases. The R1441G LRRK2 mutation is, after G2019S, the most important in PD pathogenesis. Our results demonstrate a relationship between the R1441G LRRK2 mutation and a mechanistic dysregulation of autophagy that compromises cell viability. This altered autophagy mechanism is associated with organellar stress including mitochondrial (which induces mitophagy) and endoplasmic reticulum (ER) stress, consistent with the fact that patients with this mutation are more vulnerable to toxins related to PD, such as MPP+.
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Affiliation(s)
- Sokhna M S Yakhine-Diop
- Departamento de Bioquímica Y Biología Molecular Y Genética, Facultad de Enfermería Y Terapia Ocupacional, Universidad de Extremadura, Cáceres, Spain.,Centro de Investigación Biomédica en Red de Enfermedades (CIBERNED), Madrid, Spain.,Instituto de Investigación Biosanitaria de Extremadura (INUBE), Cáceres, Spain
| | - Mario Rodríguez-Arribas
- Departamento de Bioquímica Y Biología Molecular Y Genética, Facultad de Enfermería Y Terapia Ocupacional, Universidad de Extremadura, Cáceres, Spain.,Centro de Investigación Biomédica en Red de Enfermedades (CIBERNED), Madrid, Spain.,Instituto de Investigación Biosanitaria de Extremadura (INUBE), Cáceres, Spain
| | - Saray Canales-Cortés
- Departamento de Bioquímica Y Biología Molecular Y Genética, Facultad de Enfermería Y Terapia Ocupacional, Universidad de Extremadura, Cáceres, Spain
| | - Guadalupe Martínez-Chacón
- Departamento de Bioquímica Y Biología Molecular Y Genética, Facultad de Enfermería Y Terapia Ocupacional, Universidad de Extremadura, Cáceres, Spain.,Centro de Investigación Biomédica en Red de Enfermedades (CIBERNED), Madrid, Spain.,Instituto de Investigación Biosanitaria de Extremadura (INUBE), Cáceres, Spain
| | - Elisabet Uribe-Carretero
- Departamento de Bioquímica Y Biología Molecular Y Genética, Facultad de Enfermería Y Terapia Ocupacional, Universidad de Extremadura, Cáceres, Spain.,Centro de Investigación Biomédica en Red de Enfermedades (CIBERNED), Madrid, Spain.,Instituto de Investigación Biosanitaria de Extremadura (INUBE), Cáceres, Spain
| | - Mercedes Blanco-Benítez
- Departamento de Bioquímica Y Biología Molecular Y Genética, Facultad de Enfermería Y Terapia Ocupacional, Universidad de Extremadura, Cáceres, Spain
| | - Gema Duque-González
- Departamento de Bioquímica Y Biología Molecular Y Genética, Facultad de Enfermería Y Terapia Ocupacional, Universidad de Extremadura, Cáceres, Spain
| | - Marta Paredes-Barquero
- Departamento de Bioquímica Y Biología Molecular Y Genética, Facultad de Enfermería Y Terapia Ocupacional, Universidad de Extremadura, Cáceres, Spain
| | - Eva Alegre-Cortés
- Departamento de Bioquímica Y Biología Molecular Y Genética, Facultad de Enfermería Y Terapia Ocupacional, Universidad de Extremadura, Cáceres, Spain
| | - Vicente Climent
- Departamento de Anatomía Y Embriología Humana, Facultad de Medicina, Universidad de Extremadura, Badajoz, Spain
| | - Ana Aiastui
- Cell Culture Platform, Donostia University Hospital, San Sebastián, Spain.,Neuroscience Area of Biodonostia Health Research Institute, Donostia University Hospital, San Sebastián, Spain
| | - Adolfo López de Munain
- Centro de Investigación Biomédica en Red de Enfermedades (CIBERNED), Madrid, Spain.,Department of Neurology, Donostia University Hospital, San Sebastian, Spain.,Ilundain Foundation, San Sebastian, Spain.,Department of Neurosciences, University of the Basque Country UPV-EHU, San Sebastián, Spain
| | - José M Bravo-San Pedro
- Centro de Investigación Biomédica en Red de Enfermedades (CIBERNED), Madrid, Spain.,Departamento de Fisiología, Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain
| | - Mireia Niso-Santano
- Departamento de Bioquímica Y Biología Molecular Y Genética, Facultad de Enfermería Y Terapia Ocupacional, Universidad de Extremadura, Cáceres, Spain. .,Centro de Investigación Biomédica en Red de Enfermedades (CIBERNED), Madrid, Spain. .,Instituto de Investigación Biosanitaria de Extremadura (INUBE), Cáceres, Spain.
| | - José M Fuentes
- Departamento de Bioquímica Y Biología Molecular Y Genética, Facultad de Enfermería Y Terapia Ocupacional, Universidad de Extremadura, Cáceres, Spain. .,Centro de Investigación Biomédica en Red de Enfermedades (CIBERNED), Madrid, Spain. .,Instituto de Investigación Biosanitaria de Extremadura (INUBE), Cáceres, Spain.
| | - Rosa A González-Polo
- Departamento de Bioquímica Y Biología Molecular Y Genética, Facultad de Enfermería Y Terapia Ocupacional, Universidad de Extremadura, Cáceres, Spain. .,Centro de Investigación Biomédica en Red de Enfermedades (CIBERNED), Madrid, Spain. .,Instituto de Investigación Biosanitaria de Extremadura (INUBE), Cáceres, Spain.
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6
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Pathogenic LRRK2 requires secondary factors to induce cellular toxicity. Biosci Rep 2021; 40:226517. [PMID: 32975566 PMCID: PMC7560525 DOI: 10.1042/bsr20202225] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 09/08/2020] [Accepted: 09/24/2020] [Indexed: 12/02/2022] Open
Abstract
Pathogenic mutations in the leucine-rich repeat kinase 2 (LRRK2) gene belong to the most common genetic causes of inherited Parkinson’s disease (PD) and variations in its locus increase the risk to develop sporadic PD. Extensive research efforts aimed at understanding how changes in the LRRK2 function result in molecular alterations that ultimately lead to PD. Cellular LRRK2-based models revealed several potential pathophysiological mechanisms including apoptotic cell death, LRRK2 protein accumulation and deficits in neurite outgrowth. However, highly variable outcomes between different cellular models have been reported. Here, we have investigated the effect of different experimental conditions, such as the use of different tags and gene transfer methods, in various cellular LRRK2 models. Readouts included cell death, sensitivity to oxidative stress, LRRK2 relocalization, α-synuclein aggregation and neurite outgrowth in cell culture, as well as neurite maintenance in vivo. We show that overexpression levels and/or the tag fused to LRRK2 affect the relocalization of LRRK2 to filamentous and skein-like structures. We found that overexpression of LRRK2 per se is not sufficient to induce cellular toxicity or to affect α-synuclein-induced toxicity and aggregate formation. Finally, neurite outgrowth/retraction experiments in cell lines and in vivo revealed that secondary, yet unknown, factors are required for the pathogenic LRRK2 effects on neurite length. Our findings stress the importance of technical and biological factors in LRRK2-induced cellular phenotypes and hence imply that conclusions based on these types of LRRK2-based assays should be interpreted with caution.
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7
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Wang Z, Liu Y, Ruan X, Li Y, Li E, Zhang G, Li M, Wei X. Aberrant Amplitude of Low-Frequency Fluctuations in Different Frequency Bands in Patients With Parkinson's Disease. Front Aging Neurosci 2020; 12:576682. [PMID: 33343329 PMCID: PMC7744880 DOI: 10.3389/fnagi.2020.576682] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Accepted: 10/26/2020] [Indexed: 12/16/2022] Open
Abstract
Previous studies reported abnormal spontaneous neural activity in Parkinson's disease (PD) patients using resting-state functional magnetic resonance imaging (R-fMRI). However, the frequency-dependent neural activity in PD is largely unknown. Here, 35 PD patients and 35 age- and education-matched healthy controls (HCs) underwent R-fMRI scanning to investigate abnormal spontaneous neural activity of PD using the amplitude of low-frequency fluctuation (ALFF) approach within the conventional band (typical band: 0.01-0.08 Hz) and specific frequency bands (slow-5: 0.010-0.027 Hz and slow-4: 0.027-0.073 Hz). Compared with HCs, PD patients exhibited increased ALFF in the parieto-temporo-occipital regions, such as the bilateral inferior temporal gyrus/fusiform gyrus (ITG/FG) and left angular gyrus/posterior middle temporal gyrus (AG/pMTG), and displayed decreased ALFF in the left cerebellum, right precuneus, and left postcentral gyrus/supramarginal gyrus (PostC/SMG) in the typical band. PD patients showed greater increased ALFF in the left caudate/putamen, left anterior cingulate cortex/medial superior frontal gyrus (ACC/mSFG), left middle cingulate cortex (MCC), right ITG, and left hippocampus, along with greater decreased ALFF in the left pallidum in the slow-5 band, whereas greater increased ALFF in the left ITG/FG/hippocampus accompanied by greater decreased ALFF in the precentral gyrus/PostC was found in the slow-4 band (uncorrected). Additionally, the left caudate/putamen was positively correlated with levodopa equivalent daily dose (LEDD), Hoehn and Yahr (HY) stage, and disease duration. Our results suggest that PD is related to widespread abnormal brain activities and that the abnormalities of ALFF in PD are associated with specific frequency bands. Future studies should take frequency band effects into account when examining spontaneous neural activity in PD.
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Affiliation(s)
- Zhaoxiu Wang
- Department of Radiology, Guangzhou First People’s Hospital, School of Medicine, South China University of Technology, Guangzhou, China
| | - Yanjun Liu
- Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
- Padova Neuroscience Center (PNC), University of Padova, Padua, Italy
| | - Xiuhang Ruan
- Department of Radiology, Guangzhou First People’s Hospital, School of Medicine, South China University of Technology, Guangzhou, China
| | - Yuting Li
- Department of Radiology, Guangzhou First People’s Hospital, School of Medicine, South China University of Technology, Guangzhou, China
| | - E. Li
- Department of Radiology, Guangzhou First People’s Hospital, Guangzhou Medical University, Guangzhou, China
| | - Guoqin Zhang
- Department of Radiology, Guangzhou First People’s Hospital, Guangzhou Medical University, Guangzhou, China
| | - Mengyan Li
- Department of Neurology, Guangzhou First People’s Hospital, School of Medicine, South China University of Technology, Guangzhou, China
| | - Xinhua Wei
- Department of Radiology, Guangzhou First People’s Hospital, School of Medicine, South China University of Technology, Guangzhou, China
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8
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Kamiya K, Kamagata K, Ogaki K, Hatano T, Ogawa T, Takeshige-Amano H, Murata S, Andica C, Murata K, Feiweier T, Hori M, Hattori N, Aoki S. Brain White-Matter Degeneration Due to Aging and Parkinson Disease as Revealed by Double Diffusion Encoding. Front Neurosci 2020; 14:584510. [PMID: 33177985 PMCID: PMC7594529 DOI: 10.3389/fnins.2020.584510] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 09/22/2020] [Indexed: 11/16/2022] Open
Abstract
Microstructure imaging by means of multidimensional diffusion encoding is increasingly applied in clinical research, with expectations that it yields a parameter that better correlates with clinical disability than current methods based on single diffusion encoding. Under the assumption that diffusion within a voxel can be well described by a collection of diffusion tensors, several parameters of this diffusion tensor distribution can be derived, including mean size, variance of sizes, orientational dispersion, and microscopic anisotropy. The information provided by multidimensional diffusion encoding also enables us to decompose the sources of the conventional fractional anisotropy and mean kurtosis. In this study, we explored the utility of the diffusion tensor distribution approach for characterizing white-matter degeneration in aging and in Parkinson disease by using double diffusion encoding. Data from 23 healthy older subjects and 27 patients with Parkinson disease were analyzed. Advanced age was associated with greater mean size and size variances, as well as smaller microscopic anisotropy. By analyzing the parameters underlying diffusion kurtosis, we found that the reductions of kurtosis in aging and Parkinson disease reported in the literature are likely driven by the reduction in microscopic anisotropy. Furthermore, microscopic anisotropy correlated with the severity of motor impairment in the patients with Parkinson disease. The present results support the use of multidimensional diffusion encoding in clinical studies and are encouraging for its future clinical implementation.
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Affiliation(s)
- Kouhei Kamiya
- Department of Radiology, Juntendo University School of Medicine, Tokyo, Japan.,Department of Radiology, Toho University, Tokyo, Japan
| | - Koji Kamagata
- Department of Radiology, Juntendo University School of Medicine, Tokyo, Japan
| | - Kotaro Ogaki
- Department of Neurology, Juntendo University School of Medicine, Tokyo, Japan
| | - Taku Hatano
- Department of Neurology, Juntendo University School of Medicine, Tokyo, Japan
| | - Takashi Ogawa
- Department of Neurology, Juntendo University School of Medicine, Tokyo, Japan
| | | | - Syo Murata
- Department of Radiology, Juntendo University School of Medicine, Tokyo, Japan
| | - Christina Andica
- Department of Radiology, Juntendo University School of Medicine, Tokyo, Japan
| | | | | | - Masaaki Hori
- Department of Radiology, Juntendo University School of Medicine, Tokyo, Japan.,Department of Radiology, Toho University, Tokyo, Japan
| | - Nobutaka Hattori
- Department of Neurology, Juntendo University School of Medicine, Tokyo, Japan
| | - Shigeki Aoki
- Department of Radiology, Juntendo University School of Medicine, Tokyo, Japan
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9
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Salvadores N, Court FA. The necroptosis pathway and its role in age-related neurodegenerative diseases: will it open up new therapeutic avenues in the next decade? Expert Opin Ther Targets 2020; 24:679-693. [PMID: 32310729 DOI: 10.1080/14728222.2020.1758668] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
INTRODUCTION Necroptosis is a programmed form of necrotic cell death. Growing evidence demonstrates that necroptosis contributes to cell demise in different pathological conditions including age-dependent neurodegenerative diseases (NDs). These findings open new avenues for understanding the mechanisms of neuronal loss in NDs, which might eventually translate into novel therapeutic interventions. AREAS COVERED We reviewed key aspects of necroptosis, in health and disease, focusing on evidence demonstrating its involvement in the pathogenesis of age-related NDs. We then highlight the activation of this pathway in the mechanism of axonal degeneration. We searched on PubMed the literature regarding necroptosis published between 2008 and 2020 and reviewed all publications were necroptosis was studied in the context of age-related NDs. EXPERT OPINION Axonal loss and neuronal death are the ultimate consequences of NDs that translate into disease phenotypes. Targeting degenerative mechanisms of the neuron appears as a strategy that might cover a wide range of diseases. Thus, the participation of necroptosis as a common mediator of neuronal demise emerges as a promising target for therapeutic intervention. Considering evidence demonstrating that necroptosis mediates axonal degeneration, we propose and discuss the potential of targeting necroptosis-mediated axonal destruction as a strategy to tackle NDs before neuronal loss occurs.
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Affiliation(s)
- Natalia Salvadores
- Faculty of Sciences, Center for Integrative Biology, Universidad Mayor , Santiago, Chile.,Fondap Geroscience Center for Brain Health and Metabolism , Santiago, Chile
| | - Felipe A Court
- Faculty of Sciences, Center for Integrative Biology, Universidad Mayor , Santiago, Chile.,Fondap Geroscience Center for Brain Health and Metabolism , Santiago, Chile
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10
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Alpha-Synuclein and LRRK2 in Synaptic Autophagy: Linking Early Dysfunction to Late-Stage Pathology in Parkinson's Disease. Cells 2020; 9:cells9051115. [PMID: 32365906 PMCID: PMC7290471 DOI: 10.3390/cells9051115] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Revised: 04/22/2020] [Accepted: 04/23/2020] [Indexed: 12/24/2022] Open
Abstract
The lack of effective disease-modifying strategies is the major unmet clinical need in Parkinson’s disease. Several experimental approaches have attempted to validate cellular targets and processes. Of these, autophagy has received considerable attention in the last 20 years due to its involvement in the clearance of pathologic protein aggregates and maintenance of neuronal homeostasis. However, this strategy mainly addresses a very late stage of the disease, when neuropathology and neurodegeneration have likely “tipped over the edge” and disease modification is extremely difficult. Very recently, autophagy has been demonstrated to modulate synaptic activity, a process distinct from its catabolic function. Abnormalities in synaptic transmission are an early event in neurodegeneration with Leucine-Rich Repeat Kinase 2 (LRRK2) and alpha-synuclein strongly implicated. In this review, we analyzed these processes separately and then discussed the unification of these biomolecular fields with the aim of reconstructing a potential “molecular timeline” of disease onset and progression. We postulate that the elucidation of these pathogenic mechanisms will form a critical basis for the design of novel, effective disease-modifying therapies that could be applied early in the disease process.
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11
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Richardson RJ, Fink JK, Glynn P, Hufnagel RB, Makhaeva GF, Wijeyesakere SJ. Neuropathy target esterase (NTE/PNPLA6) and organophosphorus compound-induced delayed neurotoxicity (OPIDN). ADVANCES IN NEUROTOXICOLOGY 2020; 4:1-78. [PMID: 32518884 PMCID: PMC7271139 DOI: 10.1016/bs.ant.2020.01.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Systemic inhibition of neuropathy target esterase (NTE) with certain organophosphorus (OP) compounds produces OP compound-induced delayed neurotoxicity (OPIDN), a distal degeneration of axons in the central nervous system (CNS) and peripheral nervous system (PNS), thereby providing a powerful model for studying a spectrum of neurodegenerative diseases. Axonopathies are important medical entities in their own right, but in addition, illnesses once considered primary neuronopathies are now thought to begin with axonal degeneration. These disorders include Alzheimer's disease, Parkinson's disease, and motor neuron diseases such as amyotrophic lateral sclerosis (ALS). Moreover, conditional knockout of NTE in the mouse CNS produces vacuolation and other degenerative changes in large neurons in the hippocampus, thalamus, and cerebellum, along with degeneration and swelling of axons in ascending and descending spinal cord tracts. In humans, NTE mutations cause a variety of neurodegenerative conditions resulting in a range of deficits including spastic paraplegia and blindness. Mutations in the Drosophila NTE orthologue SwissCheese (SWS) produce neurodegeneration characterized by vacuolization that can be partially rescued by expression of wild-type human NTE, suggesting a potential therapeutic approach for certain human neurological disorders. This chapter defines NTE and OPIDN, presents an overview of OP compounds, provides a rationale for NTE research, and traces the history of discovery of NTE and its relationship to OPIDN. It then briefly describes subsequent studies of NTE, including practical applications of the assay; aspects of its domain structure, subcellular localization, and tissue expression; abnormalities associated with NTE mutations, knockdown, and conventional or conditional knockout; and hypothetical models to help guide future research on elucidating the role of NTE in OPIDN.
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Affiliation(s)
- Rudy J. Richardson
- Molecular Simulations Laboratory, Department of Environmental Health Sciences, University of Michigan, Ann Arbor, MI, United States,Department of Neurology, University of Michigan Medical School, Ann Arbor, MI, United States,Center for Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann Arbor, MI, United States,Michigan Institute for Computational Discovery and Engineering, University of Michigan, Ann Arbor, MI, United States,Corresponding author:
| | - John K. Fink
- Department of Neurology, University of Michigan Medical School, Ann Arbor, MI, United States,Ann Arbor Veterans Affairs Medical Center, Ann Arbor, MI, United States
| | - Paul Glynn
- Department of Molecular and Cell Biology, University of Leicester, Leicester, United Kingdom
| | - Robert B. Hufnagel
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, MD, United States
| | - Galina F. Makhaeva
- Institute of Physiologically Active Compounds Russian Academy of Sciences, Chernogolovka, Russia
| | - Sanjeeva J. Wijeyesakere
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI, United States
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12
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The necroptosis machinery mediates axonal degeneration in a model of Parkinson disease. Cell Death Differ 2019; 27:1169-1185. [PMID: 31591470 DOI: 10.1038/s41418-019-0408-4] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Revised: 07/14/2019] [Accepted: 08/06/2019] [Indexed: 11/09/2022] Open
Abstract
Parkinson's disease (PD) is the second most common neurodegenerative condition, characterized by motor impairment due to the progressive degeneration of dopaminergic neurons in the substantia nigra and depletion of dopamine release in the striatum. Accumulating evidence suggest that degeneration of axons is an early event in the disease, involving destruction programs that are independent of the survival of the cell soma. Necroptosis, a programmed cell death process, is emerging as a mediator of neuronal loss in models of neurodegenerative diseases. Here, we demonstrate activation of necroptosis in postmortem brain tissue from PD patients and in a toxin-based mouse model of the disease. Inhibition of key components of the necroptotic pathway resulted in a significant delay of 6-hydroxydopamine-dependent axonal degeneration of dopaminergic and cortical neurons in vitro. Genetic ablation of necroptosis mediators MLKL and RIPK3, as well as pharmacological inhibition of RIPK1 in preclinical models of PD, decreased dopaminergic neuron degeneration, improving motor performance. Together, these findings suggest that axonal degeneration in PD is mediated by the necroptosis machinery, a process here referred to as necroaxoptosis, a druggable pathway to target dopaminergic neuronal loss.
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13
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Vidyadhara DJ, Lee JE, Chandra SS. Role of the endolysosomal system in Parkinson's disease. J Neurochem 2019; 150:487-506. [PMID: 31287913 PMCID: PMC6707858 DOI: 10.1111/jnc.14820] [Citation(s) in RCA: 80] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Revised: 07/01/2019] [Accepted: 07/03/2019] [Indexed: 12/13/2022]
Abstract
Parkinson's disease (PD) is one of the most common neurodegenerative disorders, affecting 1-1.5% of the total population. While progress has been made in understanding the neurodegenerative mechanisms that lead to cell death in late stages of PD, mechanisms for early, causal pathogenic events are still elusive. Recent developments in PD genetics increasingly point at endolysosomal (E-L) system dysfunction as the early pathomechanism and key pathway affected in PD. Clathrin-mediated synaptic endocytosis, an integral part of the neuronal E-L system, is probably the main early target as evident in auxilin, RME-8, and synaptojanin-1 mutations that cause PD. Autophagy, another important pathway in the E-L system, is crucial in maintaining proteostasis and a healthy mitochondrial pool, especially in neurons considering their inability to divide and requirement to function an entire life-time. PINK1 and Parkin mutations severely perturb autophagy of dysfunctional mitochondria (mitophagy), both in the cell body and synaptic terminals of dopaminergic neurons, leading to PD. Endolysosomal sorting and trafficking is also crucial, which is complex in multi-compartmentalized neurons. VPS35 and VPS13C mutations noted in PD target these mechanisms. Mutations in GBA comprise the most common risk factor for PD and initiate pathology by compromising lysosomal function. This is also the case for ATP13A2 mutations. Interestingly, α-synuclein and LRRK2, key proteins involved in PD, function in different steps of the E-L pathway and target their components to induce disease pathogenesis. In this review, we discuss these E-L system genes that are linked to PD and how their dysfunction results in PD pathogenesis. This article is part of the Special Issue "Synuclein".
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Affiliation(s)
- D J Vidyadhara
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut, USA
- Department of Neuroscience, Yale University School of Medicine, New Haven, Connecticut, USA
| | - John E Lee
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut, USA
- Department of Neuroscience, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Sreeganga S Chandra
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut, USA
- Department of Neuroscience, Yale University School of Medicine, New Haven, Connecticut, USA
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14
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Carmo M, Gonçalves FQ, Canas PM, Oses JP, Fernandes FD, Duarte FV, Palmeira CM, Tomé AR, Agostinho P, Andrade GM, Cunha RA. Enhanced ATP release and CD73-mediated adenosine formation sustain adenosine A 2A receptor over-activation in a rat model of Parkinson's disease. Br J Pharmacol 2019; 176:3666-3680. [PMID: 31220343 DOI: 10.1111/bph.14771] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2018] [Revised: 05/01/2019] [Accepted: 06/01/2019] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND AND PURPOSE Parkinson's disease (PD) involves an initial loss of striatal dopamine terminals evolving into degeneration of dopamine neurons in substantia nigra (SN), which can be modelled by 6-hydroxydopamine (6-OHDA) administration. Adenosine A2A receptor blockade attenuates PD features in animal models, but the source of the adenosine causing A2A receptor over-activation is unknown. As ATP is a stress signal, we have tested if extracellular catabolism of adenine nucleotides into adenosine (through ecto-5'-nucleotidase or CD73) leads to A2A receptor over-activation in PD. EXPERIMENTAL APPROACH Effects of blocking CD73 with α,β-methylene ADP (AOPCP) were assayed in 6-OHDA-treated rats and dopamine-differentiated neuroblastoma SH-SY5Y cells. KEY RESULTS 6-OHDA increased ATP release and extracellular conversion into adenosine through CD73 up-regulation in SH-SY5Y cells. Removing extracellular adenosine with adenosine deaminase, blocking CD73 with AOPCP, or blocking A2A receptors with SCH58261 were equi-effective in preventing 6-OHDA-induced damage in SH-SY5Y cells. In vivo striatal exposure to 6-OHDA increased ATP release and extracellular formation of adenosine from adenosine nucleotides and up-regulated CD73 and A2A receptors in striatal synaptosomes. Intracerebroventricular administration of AOPCP phenocopied effects of SCH58261, attenuating 6-OHDA-induced (a) increase of contralateral rotations after apomorphine, (b) reduction of dopamine content in striatum and SN, (c) loss of TH staining in striatum and SN, (d) motor dysfunction in the cylinder test, and (e) short-term memory impairment in the object recognition test. CONCLUSION AND IMPLICATIONS Our data indicate that increased ATP-derived adenosine formation is responsible for A2A receptor over-activation in PD, suggesting CD73 as a new target to manage PD.
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Affiliation(s)
- Marta Carmo
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,Department of Physiology and Pharmacology, Federal University of Ceará, Fortaleza, Brazil
| | - Francisco Q Gonçalves
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Paula M Canas
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Jean-Pierre Oses
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Francisco D Fernandes
- Department of Physiology and Pharmacology, Federal University of Ceará, Fortaleza, Brazil
| | - Filipe V Duarte
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Carlos M Palmeira
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,Department of Life Sciences, Faculty of Science and Technology, University of Coimbra, Coimbra, Portugal
| | - Angelo R Tomé
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,Department of Life Sciences, Faculty of Science and Technology, University of Coimbra, Coimbra, Portugal
| | - Paula Agostinho
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,FMUC-Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| | - Geanne M Andrade
- Department of Physiology and Pharmacology, Federal University of Ceará, Fortaleza, Brazil
| | - Rodrigo A Cunha
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,FMUC-Faculty of Medicine, University of Coimbra, Coimbra, Portugal
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15
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Age- and disease-related cerebral white matter changes in patients with Parkinson's disease. Neurobiol Aging 2019; 80:203-209. [DOI: 10.1016/j.neurobiolaging.2019.05.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 04/26/2019] [Accepted: 05/06/2019] [Indexed: 11/18/2022]
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16
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Ji G, Ren C, Li Y, Sun J, Liu T, Gao Y, Xue D, Shen L, Cheng W, Zhu C, Tian Y, Hu P, Chen X, Wang K. Regional and network properties of white matter function in Parkinson's disease. Hum Brain Mapp 2019; 40:1253-1263. [PMID: 30414340 PMCID: PMC6865582 DOI: 10.1002/hbm.24444] [Citation(s) in RCA: 79] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 10/05/2018] [Accepted: 10/16/2018] [Indexed: 02/01/2023] Open
Abstract
Parkinson's disease (PD) is a neurodegenerative disorder with dysfunction in cortices as well as white matter (WM) tracts. While the changes to WM structure have been extensively investigated in PD, the nature of the functional changes to WM remains unknown. In this study, the regional activity and functional connectivity of WM were compared between PD patients (n = 57) and matched healthy controls (n = 52), based on multimodel magnetic resonance imaging data sets. By tract-based spatial statistical analyses of regional activity, patients showed decreased structural-functional coupling in the left corticospinal tract compared to controls. This tract also displayed abnormally increased functional connectivity within the left post-central gyrus and left putamen in PD patients. At the network level, the WM functional network showed small-worldness in both controls and PD patients, yet it was abnormally increased in the latter group. Based on the features of the WM functional connectome, previously un-evaluated individuals could be classified with fair accuracy (73%) and area under the curve of the receiver operating characteristics (75%). These neuroimaging findings provide direct evidence for WM functional changes in PD, which is crucial to understand the functional role of fiber tracts in the pathology of neural circuits.
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Affiliation(s)
- Gong‐Jun Ji
- Department of Medical Psychology, Chaohu Clinical Medical CollegeAnhui Medical UniversityHefeiChina
| | - Cuiping Ren
- Department of Neurology, The First Affiliated Hospital of Anhui Medical UniversityHefeiChina
- Collaborative Innovation Centre of Neuropsychiatric Disorder and Mental HealthHefeiChina
- Anhui Province Key Laboratory of Cognition and Neuropsychiatric DisordersHefeiChina
| | - Ying Li
- Department of Neurology, The First Affiliated Hospital of Anhui Medical UniversityHefeiChina
- Collaborative Innovation Centre of Neuropsychiatric Disorder and Mental HealthHefeiChina
- Anhui Province Key Laboratory of Cognition and Neuropsychiatric DisordersHefeiChina
| | - Jinmei Sun
- Department of Neurology, The First Affiliated Hospital of Anhui Medical UniversityHefeiChina
- Collaborative Innovation Centre of Neuropsychiatric Disorder and Mental HealthHefeiChina
- Anhui Province Key Laboratory of Cognition and Neuropsychiatric DisordersHefeiChina
| | - Tingting Liu
- Department of Neurology, The First Affiliated Hospital of Anhui Medical UniversityHefeiChina
- Collaborative Innovation Centre of Neuropsychiatric Disorder and Mental HealthHefeiChina
- Anhui Province Key Laboratory of Cognition and Neuropsychiatric DisordersHefeiChina
| | - Yaxiang Gao
- Collaborative Innovation Centre of Neuropsychiatric Disorder and Mental HealthHefeiChina
- Anhui Province Key Laboratory of Cognition and Neuropsychiatric DisordersHefeiChina
| | - Dongzhang Xue
- Department of NeurologyThe 123 Hospital of People's Liberation ArmyBengbuChina
| | - Longshan Shen
- Department of ImagingThe Second Affiliated Hospital of Bengbu Medical CollegeBengbuChina
| | - Wen Cheng
- College of Literature and EducationBengbu CollegeBengbuChina
| | - Chunyan Zhu
- Department of Medical Psychology, Chaohu Clinical Medical CollegeAnhui Medical UniversityHefeiChina
- Collaborative Innovation Centre of Neuropsychiatric Disorder and Mental HealthHefeiChina
- Anhui Province Key Laboratory of Cognition and Neuropsychiatric DisordersHefeiChina
| | - Yanghua Tian
- Department of Neurology, The First Affiliated Hospital of Anhui Medical UniversityHefeiChina
- Collaborative Innovation Centre of Neuropsychiatric Disorder and Mental HealthHefeiChina
- Anhui Province Key Laboratory of Cognition and Neuropsychiatric DisordersHefeiChina
| | - Panpan Hu
- Department of Neurology, The First Affiliated Hospital of Anhui Medical UniversityHefeiChina
- Collaborative Innovation Centre of Neuropsychiatric Disorder and Mental HealthHefeiChina
- Anhui Province Key Laboratory of Cognition and Neuropsychiatric DisordersHefeiChina
| | - Xianwen Chen
- Department of Neurology, The First Affiliated Hospital of Anhui Medical UniversityHefeiChina
- Collaborative Innovation Centre of Neuropsychiatric Disorder and Mental HealthHefeiChina
- Anhui Province Key Laboratory of Cognition and Neuropsychiatric DisordersHefeiChina
| | - Kai Wang
- Department of Neurology, The First Affiliated Hospital of Anhui Medical UniversityHefeiChina
- Collaborative Innovation Centre of Neuropsychiatric Disorder and Mental HealthHefeiChina
- Anhui Province Key Laboratory of Cognition and Neuropsychiatric DisordersHefeiChina
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17
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Pan PY, Zhu Y, Shen Y, Yue Z. Crosstalk between presynaptic trafficking and autophagy in Parkinson's disease. Neurobiol Dis 2019; 122:64-71. [PMID: 29723605 PMCID: PMC10942671 DOI: 10.1016/j.nbd.2018.04.020] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 04/20/2018] [Accepted: 04/28/2018] [Indexed: 01/22/2023] Open
Abstract
Parkinson's disease (PD) is a debilitating neurodegenerative disorder that profoundly affects one's motor functions. The disease is characterized pathologically by denervation of dopaminergic (DAergic) nigrostriatal terminal and degeneration of DAergic neurons in the substantia nigra par compacta (SNpc); however, the precise molecular mechanism underlying disease pathogenesis remains poorly understood. Animal studies in both toxin-induced and genetic PD models suggest that presynaptic impairments may underlie the early stage of DA depletion and neurodegeneration (reviewed in Schirinzi, T., et al. 2016). Supporting this notion, human genetic studies and genomic analysis have identified an increasing number of PD risk variants that are associated with synaptic vesicle (SV) trafficking, regulation of synaptic function and autophagy/lysosomal system (Chang, D., et al. 2017, reviewed in Trinh, J. & Farrer, M. 2013; Singleton, A.B., et al. 2013). Although the precise mechanism for autophagy regulation in neurons is currently unclear, many studies demonstrate that autophagosomes form at the presynaptic terminal (Maday, S. & Holzbaur, E.L. 2014; Vanhauwaert, R., et al. 2017; reviewed in Yue, Z. 2007). Growing evidence has revealed overlapping genes involved in both SV recycling and autophagy, suggesting that the two membrane trafficking processes are inter-connected. Here we will review emergent evidence linking SV endocytic genes and autophagy genes at the presynaptic terminal. We will discuss their potential relevance to PD pathogenesis.
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Affiliation(s)
- Ping-Yue Pan
- Department of Neurology, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, Hess Research Center 9th Floor, New York, NY 10029, USA
| | - Yingbo Zhu
- Department of Psychiatry, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai 200072, China
| | - Yuan Shen
- Department of Psychiatry, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai 200072, China
| | - Zhenyu Yue
- Department of Neurology, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, Hess Research Center 9th Floor, New York, NY 10029, USA.
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18
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Fahn S, Sulzer D, Kang UJ, Bressman S. In memoriam: Robert E. Burke, MD, 1949–2018. Mov Disord 2019. [DOI: 10.1002/mds.27612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Stanley Fahn
- Division of Movement Disorders, Department of Neurology Columbia University Irving Medical Center New York New York USA
| | - David Sulzer
- Division of Movement Disorders, Department of Neurology Columbia University Irving Medical Center New York New York USA
- Departments of Psychiatry, Neurology and Pharmacology Columbia University Irving Medical Center New York New York USA
| | - Un Jung Kang
- Division of Movement Disorders, Department of Neurology Columbia University Irving Medical Center New York New York USA
| | - Susan Bressman
- Department of Neurology, Beth Israel Campus Mount Sinai Medical Center New York New York USA
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19
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Tozzi A, Durante V, Bastioli G, Mazzocchetti P, Novello S, Mechelli A, Morari M, Costa C, Mancini A, Di Filippo M, Calabresi P. Dopamine D2 receptor activation potently inhibits striatal glutamatergic transmission in a G2019S LRRK2 genetic model of Parkinson's disease. Neurobiol Dis 2018; 118:1-8. [DOI: 10.1016/j.nbd.2018.06.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 06/04/2018] [Accepted: 06/12/2018] [Indexed: 12/28/2022] Open
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20
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Abstract
LRRK2 mutations are associated with the loss of neurons, that is to say toxicity, in patients and in experimental model systems. However, the mechanisms by which mutations can be linked to neurodegeneration are not fully defined. Here I will argue that mechanism in this context encompasses a variety of levels of information. Mutations or alterations in gene expression at a genetic level are one set of mechanisms that are reflected at the biochemical level likely in enhanced or persistent function of LRRK2. By impacting cellular pathways, prominently including changes in autophagy but also microtubule function, mitochondria and protein synthesis, in neurons and immune cells, the LRRK2 brain is primed for neurodegeneration in an age-dependent manner. These concepts have implications for not only modeling LRRK2 disease but also perhaps for Parkinson's disease more generally, including the development of therapeutic modalities.
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21
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Sasaki Y. Metabolic aspects of neuronal degeneration: From a NAD + point of view. Neurosci Res 2018; 139:9-20. [PMID: 30006197 DOI: 10.1016/j.neures.2018.07.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 06/21/2018] [Accepted: 06/22/2018] [Indexed: 12/14/2022]
Abstract
Cellular metabolism maintains the life of cells, allowing energy production required for building cellular constituents and maintaining homeostasis under constantly changing external environments. Neuronal cells maintain their structure and function for the entire life of organisms and the loss of neurons, with limited neurogenesis in adults, directly causes loss of complexity in the neuronal networks. The nervous system organizes the neurons by placing cell bodies containing nuclei of similar types of neurons in discrete regions. Accordingly, axons must travel great distances to connect different types of neurons and peripheral organs. The enormous surface area of neurons makes them high-energy demanding to keep their membrane potential. Distal axon survival is dependent on axonal transport that is another energy demanding process. All of these factors make metabolic stress a potential risk factor for neuronal death and neuronal degeneration often associated with metabolic diseases. This review discusses recent findings on metabolic dysregulations under neuronal degeneration and pathways protecting neurons in these conditions.
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Affiliation(s)
- Yo Sasaki
- Department of Genetics, Washington University in St. Louis, Couch Biomedical Research Building, 4515 McKinley Ave., Saint Louis, MO, 63110, United States
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22
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Sheehan P, Yue Z. Deregulation of autophagy and vesicle trafficking in Parkinson's disease. Neurosci Lett 2018; 697:59-65. [PMID: 29627340 DOI: 10.1016/j.neulet.2018.04.013] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Revised: 04/03/2018] [Accepted: 04/04/2018] [Indexed: 12/19/2022]
Abstract
Parkinson's disease (PD) is a common neurodegenerative disease characterized pathologically by the selective loss of dopaminergic neurons in the substantia nigra and the intracellular accumulation of α-synuclein in the Lewy bodies. While the pathogenic mechanisms of PD are poorly understood, many lines of evidence point to a role of altered autophagy and membrane trafficking in the development of the disease. Emerging studies show that connections between the deregulation of autophagy and synaptic vesicle (SV) trafficking may contribute to PD. Here we review the evidence that many PD related-genes have roles in both autophagy and SV trafficking and examine how deregulation of these pathways contributes to PD pathogenesis. This review also discusses recent studies aimed at uncovering the role of PD-linked genes in autophagy-lysosome function.
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Affiliation(s)
- Patricia Sheehan
- Department of Neurology, The Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, 10029, USA
| | - Zhenyu Yue
- Department of Neurology, The Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, 10029, USA.
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23
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Tozzi A, Tantucci M, Marchi S, Mazzocchetti P, Morari M, Pinton P, Mancini A, Calabresi P. Dopamine D2 receptor-mediated neuroprotection in a G2019S Lrrk2 genetic model of Parkinson's disease. Cell Death Dis 2018; 9:204. [PMID: 29434188 PMCID: PMC5833812 DOI: 10.1038/s41419-017-0221-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Revised: 12/04/2017] [Accepted: 12/12/2017] [Indexed: 12/17/2022]
Abstract
Parkinson's disease (PD) is a neurodegenerative disorder in which genetic and environmental factors synergistically lead to loss of midbrain dopamine (DA) neurons. Mutation of leucine-rich repeated kinase2 (Lrrk2) genes is responsible for the majority of inherited familial cases of PD and can also be found in sporadic cases. The pathophysiological role of this kinase has to be fully understood yet. Hyperactivation of Lrrk2 kinase domain might represent a predisposing factor for both enhanced striatal glutamatergic release and mitochondrial vulnerability to environmental factors that are observed in PD. To investigate possible alterations of striatal susceptibility to mitochondrial dysfunction, we performed electrophysiological recordings from the nucleus striatum of a G2019S Lrrk2 mouse model of PD, as well as molecular and morphological analyses of G2019S Lrrk2-expressing SH-SY5Y neuroblastoma cells. In G2019S mice, we found reduced striatal DA levels, according to the hypothesis of alteration of dopaminergic transmission, and increased loss of field potential induced by the mitochondrial complex I inhibitor rotenone. This detrimental effect is reversed by the D2 DA receptor agonist quinpirole via the inhibition of the cAMP/PKA intracellular pathway. Analysis of mitochondrial functions in G2019S Lrrk2-expressing SH-SY5Y cells revealed strong rotenone-induced oxidative stress characterized by reduced Ca2+ buffering capability and ATP synthesis, production of reactive oxygen species, and increased mitochondrial fragmentation. Importantly, quinpirole was able to prevent all these changes. We suggest that the G2019S-Lrrk2 mutation is a predisposing factor for enhanced striatal susceptibility to mitochondrial dysfunction induced by exposure to mitochondrial environmental toxins and that the D2 receptor stimulation is neuroprotective on mitochondrial function, via the inhibition of cAMP/PKA intracellular pathway. We suggest new possible neuroprotective strategies for patients carrying this genetic alteration based on drugs specifically targeting Lrrk2 kinase domain and mitochondrial functionality.
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Affiliation(s)
- Alessandro Tozzi
- Santa Lucia Foundation IRCCS, Rome, Italy
- Department of Experimental Medicine, Section of Physiology and Biochemistry, University of Perugia, Perugia, Italy
| | - Michela Tantucci
- Neurological clinic, Department of Medicine, University of Perugia, Santa Maria della Misericordia Hospital, Perugia, Italy
| | - Saverio Marchi
- Department of Morphology, Surgery and Experimental Medicine, University of Ferrara, Ferrara, Italy
| | - Petra Mazzocchetti
- Neurological clinic, Department of Medicine, University of Perugia, Santa Maria della Misericordia Hospital, Perugia, Italy
| | - Michele Morari
- Department of Medical Sciences, University of Ferrara, Ferrara, Italy
| | - Paolo Pinton
- Department of Morphology, Surgery and Experimental Medicine, University of Ferrara, Ferrara, Italy
| | - Andrea Mancini
- Neurological clinic, Department of Medicine, University of Perugia, Santa Maria della Misericordia Hospital, Perugia, Italy
| | - Paolo Calabresi
- Santa Lucia Foundation IRCCS, Rome, Italy.
- Neurological clinic, Department of Medicine, University of Perugia, Santa Maria della Misericordia Hospital, Perugia, Italy.
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24
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Jiang P, Dickson DW. Parkinson's disease: experimental models and reality. Acta Neuropathol 2018; 135:13-32. [PMID: 29151169 PMCID: PMC5828522 DOI: 10.1007/s00401-017-1788-5] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 11/08/2017] [Accepted: 11/09/2017] [Indexed: 12/15/2022]
Abstract
Parkinson's disease (PD) is a chronic, progressive movement disorder of adults and the second most common neurodegenerative disease after Alzheimer's disease. Neuropathologic diagnosis of PD requires moderate-to-marked neuronal loss in the ventrolateral substantia nigra pars compacta and α-synuclein (αS) Lewy body pathology. Nigrostriatal dopaminergic neurodegeneration correlates with the Parkinsonian motor features, but involvement of other peripheral and central nervous system regions leads to a wide range of non-motor features. Nigrostriatal dopaminergic neurodegeneration is shared with other parkinsonian disorders, including some genetic forms of parkinsonism, but many of these disorders do not have Lewy bodies. An ideal animal model for PD, therefore, should exhibit age-dependent and progressive dopaminergic neurodegeneration, motor dysfunction, and abnormal αS pathology. Rodent models of PD using genetic or toxin based strategies have been widely used in the past several decades to investigate the pathogenesis and therapeutics of PD, but few recapitulate all the major clinical and pathologic features of PD. It is likely that new strategies or better understanding of fundamental disease processes may facilitate development of better animal models. In this review, we highlight progress in generating rodent models of PD based on impairments of four major cellular functions: mitochondrial oxidative phosphorylation, autophagy-lysosomal metabolism, ubiquitin-proteasome protein degradation, and endoplasmic reticulum stress/unfolded protein response. We attempt to evaluate how impairment of these major cellular systems contribute to PD and how they can be exploited in rodent models. In addition, we review recent cell biological studies suggesting a link between αS aggregation and impairment of nuclear membrane integrity, as observed during cellular models of apoptosis. We also briefly discuss the role of incompetent phagocytic clearance and how this may be a factor to consider in developing new rodent models of PD.
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Affiliation(s)
- Peizhou Jiang
- Neuropathology Laboratory, Department of Neuroscience, Mayo Clinic, 4500 San Pablo Road, Jacksonville, FL, 32224, USA
| | - Dennis W Dickson
- Neuropathology Laboratory, Department of Neuroscience, Mayo Clinic, 4500 San Pablo Road, Jacksonville, FL, 32224, USA.
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25
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Kurowska Z, Kordower JH, Stoessl AJ, Burke RE, Brundin P, Yue Z, Brady ST, Milbrandt J, Trapp BD, Sherer TB, Medicetty S. Is Axonal Degeneration a Key Early Event in Parkinson's Disease? JOURNAL OF PARKINSONS DISEASE 2017; 6:703-707. [PMID: 27497486 DOI: 10.3233/jpd-160881] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Recent research suggests that in Parkinson's disease the long, thin and unmyelinated axons of dopaminergic neurons degenerate early in the disease process. We organized a workshop entitled 'Axonal Pathology in Parkinson's disease', on March 23rd, 2016, in Cleveland, Ohio with the goals of summarizing the state-of-the-art and defining key gaps in knowledge. A group of eight research leaders discussed new developments in clinical pathology, functional imaging, animal models, and mechanisms of degeneration including neuroinflammation, autophagy and axonal transport deficits. While the workshop focused on PD, comparisons were made to other neurological conditions where axonal degeneration is well recognized.
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Affiliation(s)
- Zuzanna Kurowska
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA.,Renovo Neural Inc., Cleveland, OH, USA
| | - Jeffrey H Kordower
- Research Center for Brain Repair, Rush University Medical Center, Chicago, IL, USA.,Van Andel Research Institute, Center for Neurodegenerative Science, Grand Rapids, MI, USA
| | - A Jon Stoessl
- Pacific Parkinson's Research Centre, Division of Neurology and Djavad Mowafaghian Centre for Brain Health, University of British Columbia and Vancouver Coastal Health, BC, Canada
| | - Robert E Burke
- Departments of Neurology and Pathology & Cell Biology, Columbia University Medical Center, New York City, NY, USA
| | - Patrik Brundin
- Van Andel Research Institute, Center for Neurodegenerative Science, Grand Rapids, MI, USA
| | - Zhenyu Yue
- Departments of Neurology and Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Scott T Brady
- Department of Anatomy and Cell Biology, University of Illinois at Chicago, Chicago, IL, USA; Marine Biological Laboratory, Woods Hole, MA, USA
| | - Jeffrey Milbrandt
- Department of Genetics, Washington University School of Medicine in St. Louis, St. Louis, MO, USA; Hope Center for Neurological Disorders, Washington University School of Medicine in St. Louis, St. Louis, MO, USA
| | - Bruce D Trapp
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA.,Renovo Neural Inc., Cleveland, OH, USA
| | - Todd B Sherer
- The Michael J. Fox Foundation for Parkinson's Research, New York, NY, USA
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26
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Hegarty SV, Wyatt SL, Howard L, Stappers E, Huylebroeck D, Sullivan AM, O'Keeffe GW. Zeb2 is a negative regulator of midbrain dopaminergic axon growth and target innervation. Sci Rep 2017; 7:8568. [PMID: 28819210 PMCID: PMC5561083 DOI: 10.1038/s41598-017-08900-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 07/14/2017] [Indexed: 11/09/2022] Open
Abstract
Neural connectivity requires neuronal differentiation, axon growth, and precise target innervation. Midbrain dopaminergic neurons project via the nigrostriatal pathway to the striatum to regulate voluntary movement. While the specification and differentiation of these neurons have been extensively studied, the molecular mechanisms that regulate midbrain dopaminergic axon growth and target innervation are less clear. Here we show that the transcription factor Zeb2 cell-autonomously represses Smad signalling to limit midbrain dopaminergic axon growth and target innervation. Zeb2 levels are downregulated in the embryonic rodent midbrain during the period of dopaminergic axon growth, when BMP pathway components are upregulated. Experimental knockdown of Zeb2 leads to an increase in BMP-Smad-dependent axon growth. Consequently there is dopaminergic hyperinnervation of the striatum, without an increase in the numbers of midbrain dopaminergic neurons, in conditional Zeb2 (Nestin-Cre based) knockout mice. Therefore, these findings reveal a new mechanism for the regulation of midbrain dopaminergic axon growth during central nervous system development.
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Affiliation(s)
- Shane V Hegarty
- Department of Anatomy & Neuroscience, University College Cork (UCC), Cork, Ireland
| | - Sean L Wyatt
- School of Biosciences, Cardiff University, Museum Avenue, Cardiff, CF10 3AT, UK
| | - Laura Howard
- School of Biosciences, Cardiff University, Museum Avenue, Cardiff, CF10 3AT, UK
| | - Elke Stappers
- Department of Development and Regeneration, Laboratory of Molecular Biology (Celgen), KU Leuven, 3000, Leuven, Belgium.,Department of Cell Biology, Erasmus University Medical Center, 3015 CN, Rotterdam, The Netherlands
| | - Danny Huylebroeck
- Department of Development and Regeneration, Laboratory of Molecular Biology (Celgen), KU Leuven, 3000, Leuven, Belgium.,Department of Cell Biology, Erasmus University Medical Center, 3015 CN, Rotterdam, The Netherlands
| | - Aideen M Sullivan
- Department of Anatomy & Neuroscience, University College Cork (UCC), Cork, Ireland. .,APC Microbiome Institute, UCC, Cork, Ireland.
| | - Gerard W O'Keeffe
- Department of Anatomy & Neuroscience, University College Cork (UCC), Cork, Ireland. .,APC Microbiome Institute, UCC, Cork, Ireland. .,The INFANT Centre, CUMH and UCC, Cork, Ireland.
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27
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Phan JA, Stokholm K, Zareba-Paslawska J, Jakobsen S, Vang K, Gjedde A, Landau AM, Romero-Ramos M. Early synaptic dysfunction induced by α-synuclein in a rat model of Parkinson's disease. Sci Rep 2017; 7:6363. [PMID: 28743955 PMCID: PMC5526979 DOI: 10.1038/s41598-017-06724-9] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Accepted: 06/15/2017] [Indexed: 02/08/2023] Open
Abstract
Evidence suggests that synapses are affected first in Parkinson’s disease (PD). Here, we tested the claim that pathological accumulation of α-synuclein, and subsequent synaptic disruption, occur in absence of dopaminergic neuron loss in PD. We determined early synaptic changes in rats that overexpress human α-synuclein by local injection of viral-vectors in midbrain. We aimed to achieve α-synuclein levels sufficient to induce terminal pathology without significant loss of nigral neurons. We tested synaptic disruption in vivo by analyzing motor defects and binding of a positron emission tomography (PET) radioligand to the vesicular monoamine transporter 2, (VMAT2), [11C]dihydrotetrabenazine (DTBZ). Animals overexpressing α-synuclein had progressive motor impairment and, 12 weeks post-surgery, showed asymmetric in vivo striatal DTBZ binding. The PET images matched ligand binding in post-mortem tissue, and histological markers of dopaminergic integrity. Histology confirmed the absence of nigral cell death with concomitant significant loss of striatal terminals. Progressive aggregation of proteinase-K resistant and Ser129-phosphorylated α-synuclein was observed in dopaminergic terminals, in dystrophic swellings that resembled axonal spheroids and contained mitochondria and vesicular proteins. In conclusion, pathological α-synuclein in nigro-striatal axonal terminals leads to early axonal pathology, synaptic disruption, dysfunction of dopaminergic neurotransmission, motor impairment, and measurable change of VMAT2 in the absence of cell loss.
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Affiliation(s)
- Jenny-Ann Phan
- Department of Biomedicine, NEURODIN AU IDEAS Center, Aarhus University, Wilhelm Meyers Allé 4, bldg. 1242, Aarhus C, 8000, Denmark.,Department of Nuclear Medicine and PET Centre, Aarhus University and Hospital, Norrebrogade 44, bldg. 10G, Aarhus C, 8000, Denmark
| | - Kathrine Stokholm
- Department of Biomedicine, NEURODIN AU IDEAS Center, Aarhus University, Wilhelm Meyers Allé 4, bldg. 1242, Aarhus C, 8000, Denmark.,Department of Nuclear Medicine and PET Centre, Aarhus University and Hospital, Norrebrogade 44, bldg. 10G, Aarhus C, 8000, Denmark
| | - Justyna Zareba-Paslawska
- Department of Biomedicine, NEURODIN AU IDEAS Center, Aarhus University, Wilhelm Meyers Allé 4, bldg. 1242, Aarhus C, 8000, Denmark
| | - Steen Jakobsen
- Department of Nuclear Medicine and PET Centre, Aarhus University and Hospital, Norrebrogade 44, bldg. 10G, Aarhus C, 8000, Denmark
| | - Kim Vang
- Department of Nuclear Medicine and PET Centre, Aarhus University and Hospital, Norrebrogade 44, bldg. 10G, Aarhus C, 8000, Denmark
| | - Albert Gjedde
- Department of Neuroscience and Pharmacology, University of Copenhagen, Blegdamsvej 3, Copenhagen, 2200, Denmark.,Center of Neuroscience, University of Copenhagen, Copenhagen, Denmark.,Dept of Radiology & Radiological Science, Johns Hopkins University, Baltimore, MD, USA.,Department of Neurology and Neurosurgery, McGill University, Montreal, Quebec, Canada.,Neurosciences Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.,Department of Clinical Medicine, University of Southern Denmark, Odense, Denmark
| | - Anne M Landau
- Department of Nuclear Medicine and PET Centre, Aarhus University and Hospital, Norrebrogade 44, bldg. 10G, Aarhus C, 8000, Denmark. .,Translational Neuropsychiatry Unit, Aarhus University, Skovagervej 2, Risskov, 8240, Denmark.
| | - Marina Romero-Ramos
- Department of Biomedicine, NEURODIN AU IDEAS Center, Aarhus University, Wilhelm Meyers Allé 4, bldg. 1242, Aarhus C, 8000, Denmark.
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28
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Giesert F, Glasl L, Zimprich A, Ernst L, Piccoli G, Stautner C, Zerle J, Hölter SM, Vogt Weisenhorn DM, Wurst W. The pathogenic LRRK2 R1441C mutation induces specific deficits modeling the prodromal phase of Parkinson's disease in the mouse. Neurobiol Dis 2017; 105:179-193. [PMID: 28576705 DOI: 10.1016/j.nbd.2017.05.013] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2017] [Revised: 05/13/2017] [Accepted: 05/29/2017] [Indexed: 12/11/2022] Open
Abstract
The aim of the present study was to further explore the in vivo function of the Leucine-rich repeat kinase 2 (LRRK2)-gene, which is mutated in certain familial forms of Parkinson's disease (PD). We generated a mouse model harboring the disease-associated point mutation R1441C in the GTPase domain of the endogenous murine LRRK2 gene (LRRK2 R1441C line) and performed a comprehensive analysis of these animals throughout lifespan in comparison with an existing knockdown line of LRRK2 (LRRK2 knockdown line). Animals of both lines do not exhibit severe motor dysfunction or pathological signs of neurodegeneration neither at young nor old age. However, at old age the homozygous LRRK2 R1441C animals exhibit clear phenotypes related to the prodromal phase of PD such as impairments in fine motor tasks, gait, and olfaction. These phenotypes are only marginally observable in the LRRK2 knockdown animals, possibly due to activation of compensatory mechanisms as suggested by in vitro studies of synaptic transmission. Thus, at the organismal level the LRRK2 R1441C mutation does not emerge as a loss of function of the protein, but induces mutation specific deficits. Furthermore, judged by the phenotypes presented, the LRRK2-R1441C knock-in line is a valid preclinical model for the prodromal phase of PD.
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Affiliation(s)
- F Giesert
- Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Developmental Genetics, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany; Technische Universität München-Weihenstephan, Lehrstuhl für Entwicklungsgenetik, c/o Helmholtz Zentrum München, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
| | - L Glasl
- Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Developmental Genetics, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
| | - A Zimprich
- Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Developmental Genetics, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
| | - L Ernst
- Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Developmental Genetics, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
| | - G Piccoli
- Center for Integrative Biology (CIBIO), University of Trento and Dulbecco Telethon Institute Trento, Italy
| | - C Stautner
- Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Developmental Genetics, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
| | - J Zerle
- Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Developmental Genetics, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
| | - S M Hölter
- Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Developmental Genetics, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
| | - D M Vogt Weisenhorn
- Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Developmental Genetics, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany; Technische Universität München-Weihenstephan, Lehrstuhl für Entwicklungsgenetik, c/o Helmholtz Zentrum München, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
| | - W Wurst
- Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Developmental Genetics, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany; Technische Universität München-Weihenstephan, Lehrstuhl für Entwicklungsgenetik, c/o Helmholtz Zentrum München, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany; Munich Cluster for Systems Neurology (SyNergy), Feodor-Lynen-Str. 17, 81377 Munich, Germany; Deutsches Zentrum für Neurodegenerative Erkrankungen e. V. (DZNE), Standort München, Feodor-Lynen-Str. 17, 81377 München, Germany.
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29
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Targeting bone morphogenetic protein signalling in midbrain dopaminergic neurons as a therapeutic approach in Parkinson's disease. Neuronal Signal 2017; 1:NS20170027. [PMID: 32714578 PMCID: PMC7373244 DOI: 10.1042/ns20170027] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Revised: 02/20/2017] [Accepted: 02/23/2017] [Indexed: 11/17/2022] Open
Abstract
Parkinson's disease (PD) is the second most common neurodegenerative disease, characterized by the degeneration of midbrain dopaminergic (mDA) neurons and their axons, and aggregation of α-synuclein, which leads to motor and late-stage cognitive impairments. As the motor symptoms of PD are caused by the degeneration of a specific population of mDA neurons, PD lends itself to neurotrophic factor therapy. The goal of this therapy is to apply a neurotrophic factor that can slow down, halt or even reverse the progressive degeneration of mDA neurons. While the best known neurotrophic factors are members of the glial cell line-derived neurotrophic factor (GDNF) family, their lack of clinical efficacy to date means that it is important to continue to study other neurotrophic factors. Bone morphogenetic proteins (BMPs) are naturally secreted proteins that play critical roles during nervous system development and in the adult brain. In this review, we provide an overview of the BMP ligands, BMP receptors (BMPRs) and their intracellular signalling effectors, the Smad proteins. We review the available evidence that BMP-Smad signalling pathways play an endogenous role in mDA neuronal survival in vivo, before outlining how exogenous application of BMPs exerts potent effects on mDA neuron survival and axon growth in vitro and in vivo. We discuss the molecular mechanisms that mediate these effects, before highlighting the potential of targeting the downstream effectors of BMP-Smad signalling as a novel neuroprotective approach to slow or stop the degeneration of mDA neurons in PD.
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30
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Liu HF, Ho PWL, Leung GCT, Lam CSC, Pang SYY, Li L, Kung MHW, Ramsden DB, Ho SL. Combined LRRK2 mutation, aging and chronic low dose oral rotenone as a model of Parkinson's disease. Sci Rep 2017; 7:40887. [PMID: 28098219 PMCID: PMC5241661 DOI: 10.1038/srep40887] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Accepted: 11/22/2016] [Indexed: 12/18/2022] Open
Abstract
Aging, genetics and environmental toxicity are important etiological factors in Parkinson’s disease (PD). However, its pathogenesis remains unclear. A major obstacle is the lack of an appropriate experimental model which incorporates genetic susceptibility, aging and prolonged environmental toxicity. Here, we explored the interplay amongst these factors using mutant LRRK2R1441G (leucine-rich-repeat-kinase-2) knockin mice. We found that mutant primary cortical and mesencephalic dopaminergic neurons were more susceptible to rotenone-induced ATP deficiency and cell death. Compared with wild-type controls, striatal synaptosomes isolated from young mutant mice exhibited significantly lower dopamine uptake after rotenone toxicity, due to reduced striatal synaptosomal mitochondria and synaptic vesicular proton pump protein (V-ATPase H) levels. Mutant mice developed greater locomotor deficits in open-field tests than wild-type mice following low oral rotenone doses given twice weekly over 50 weeks (half their lifespan). The increased locomotor deficit was associated with specific reduction in striatal mitochondrial Complex-I (NDUFS4) in rotenone-treated mutant but not in similarly treated wild-type mice. Our unique experimental model which incorporates genetic effect, natural aging and prolonged oral environmental toxicity administered to mutant knockin LRRK2 mice over half their life span, with observable and measurable phenotype, is invaluable in further studies of the pathogenic process and therapeutics of PD.
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Affiliation(s)
- Hui-Fang Liu
- Division of Neurology, Department of Medicine, University of Hong Kong, Hong Kong
| | - Philip Wing-Lok Ho
- Division of Neurology, Department of Medicine, University of Hong Kong, Hong Kong
| | | | - Colin Siu-Chi Lam
- Division of Neurology, Department of Medicine, University of Hong Kong, Hong Kong
| | - Shirley Yin-Yu Pang
- Division of Neurology, Department of Medicine, University of Hong Kong, Hong Kong
| | - Lingfei Li
- Division of Neurology, Department of Medicine, University of Hong Kong, Hong Kong
| | | | - David Boyer Ramsden
- Institute of Metabolism and Systems Research, University of Birmingham, United Kingdom
| | - Shu-Leong Ho
- Division of Neurology, Department of Medicine, University of Hong Kong, Hong Kong
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31
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Tagliaferro P, Burke RE. Retrograde Axonal Degeneration in Parkinson Disease. JOURNAL OF PARKINSONS DISEASE 2017; 6:1-15. [PMID: 27003783 PMCID: PMC4927911 DOI: 10.3233/jpd-150769] [Citation(s) in RCA: 161] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
In spite of tremendous research efforts we have not yet achieved two of our principal therapeutic goals in the treatment of Parkinson’s disease (PD), to prevent its onward progression and to provide restoration of systems that have already been damaged by the time of diagnosis. There are many possible reasons for our inability to make progress. One possibility is that our efforts thus far may not have been directed towards the appropriate cellular compartments. Up until now research has been largely focused on the loss of neurons in the disease. Thus, neuroprotection approaches have been largely aimed at blocking mechanisms that lead to destruction of the neuronal cell body. Attempts to provide neurorestoration have been almost entirely focused on replacement of neurons. We herein review the evidence that the axonal component of diseased neuronal systems merit more of our attention. Evidence from imaging studies, from postmortem neurochemical studies, and from genetic animal models suggests that the axons of the dopaminergic system are involved predominantly and early in PD. Since the mechanisms of axonal destruction are distinct from those of neuron cell body degeneration, a focus on axonal neurobiology will offer new opportunities for preventing their degeneration. At present these mechanisms remain largely obscure. However, defining them is likely to offer new opportunities for neuroprotection. In relation to neurorestoration, while it has been classically believed that neurons of the adult central nervous system are incapable of new axon growth, recent evidence shows that this is not true for the dopaminergic projection. In conclusion, the neurobiology of axons is likely to offer many new approaches to protective and restorative therapeutics.
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Affiliation(s)
| | - Robert E Burke
- Department of Neurology, Columbia University Medical Center, New York, NY, USA.,Departments of Pathology and Cell Biology, Columbia University Medical Center, New York, NY, USA
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32
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Thomas JM, Li T, Yang W, Xue F, Fishman PS, Smith WW. 68 and FX2149 Attenuate Mutant LRRK2-R1441C-Induced Neural Transport Impairment. Front Aging Neurosci 2017; 8:337. [PMID: 28119604 PMCID: PMC5222795 DOI: 10.3389/fnagi.2016.00337] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Accepted: 12/26/2016] [Indexed: 11/27/2022] Open
Abstract
Leucine-rich repeat kinase 2 is a large protein with implications in genetic and sporadic causes of Parkinson's disease. The physiological functions of LRRK2 are largely unknown. In this report, we investigated whether LRRK2 alters neural transport using live-cell imaging techniques and human neuroblastoma SH-SY5Y cells. Our results demonstrated that expression of the PD-linked mutant, LRRK2-R1441C, induced mitochondrial, and lysosomal transport defects in neurites of SH-SY5Y cells. Most importantly, recently identified GTP-binding inhibitors, 68 and FX2149, can reduce LRRK2 GTP-binding activity and attenuates R1441C-induced mitochondrial and lysosomal transport impairments. These results provide direct evidence and an early mechanism for neurite injury underlying LRRK2-induced neurodegeneration. This is the first report to show that LRRK2 GTP-binding activity plays a critical role during neurite transport, suggesting inhibition of LRRK2 GTP-binding could be a potential novel strategy for PD intervention.
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Affiliation(s)
- Joseph M Thomas
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy Baltimore, MD, USA
| | - Tianxia Li
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy Baltimore, MD, USA
| | - Wei Yang
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy Baltimore, MD, USA
| | - Fengtian Xue
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy Baltimore, MD, USA
| | - Paul S Fishman
- Department of Neurology, University of Maryland School of MedicineBaltimore, MD, USA; Neurology Service, VA Maryland Healthcare SystemBaltimore, MD, USA
| | - Wanli W Smith
- Department of Psychiatry, Johns Hopkins University School of Medicine Baltimore, MD, USA
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33
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Nguyen APT, Moore DJ. Understanding the GTPase Activity of LRRK2: Regulation, Function, and Neurotoxicity. ADVANCES IN NEUROBIOLOGY 2017; 14:71-88. [PMID: 28353279 DOI: 10.1007/978-3-319-49969-7_4] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Mutations in the leucine-rich repeat kinase 2 (LRRK2) gene are the most frequent cause of Parkinson's disease (PD) with late-onset and autosomal-dominant inheritance. LRRK2 belongs to the ROCO superfamily of proteins, characterized by a Ras-of-complex (Roc) GTPase domain in tandem with a C-terminal-of-Roc (COR) domain. LRRK2 also contains a protein kinase domain adjacent to the Roc-COR tandem domain in addition to multiple repeat domains. Disease-causing familial mutations cluster within the Roc-COR tandem and kinase domains of LRRK2, where they act to either impair GTPase activity or enhance kinase activity. Familial LRRK2 mutations share in common the capacity to induce neuronal toxicity in cultured cells. While the contribution of the frequent G2019S mutation, located within the kinase domain, to kinase activity and neurotoxicity has been extensively investigated, the contribution of GTPase activity has received less attention. The GTPase domain has been shown to play an important role in regulating kinase activity, in dimerization, and in mediating the neurotoxic effects of LRRK2. Accordingly, the GTPase domain has emerged as a potential therapeutic target for inhibiting the pathogenic effects of LRRK2 mutations. Many important mechanisms remain to be elucidated, including how the GTPase cycle of LRRK2 is regulated, whether GTPase effectors exist for LRRK2, and how GTPase activity contributes to the overall functional output of LRRK2. In this review, we discuss the importance of the GTPase domain for LRRK2-linked PD focusing in particular on its regulation, function, and contribution to neurotoxic mechanisms.
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Affiliation(s)
- An Phu Tran Nguyen
- Center for Neurodegenerative Science, Van Andel Research Institute, 333 Bostwick Ave NE, Grand Rapids, MI, 49503, USA
| | - Darren J Moore
- Center for Neurodegenerative Science, Van Andel Research Institute, 333 Bostwick Ave NE, Grand Rapids, MI, 49503, USA.
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34
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Tinaz S, Lauro PM, Ghosh P, Lungu C, Horovitz SG. Changes in functional organization and white matter integrity in the connectome in Parkinson's disease. NEUROIMAGE-CLINICAL 2016; 13:395-404. [PMID: 28116232 PMCID: PMC5226806 DOI: 10.1016/j.nicl.2016.12.019] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Revised: 12/08/2016] [Accepted: 12/16/2016] [Indexed: 11/27/2022]
Abstract
Parkinson's disease (PD) leads to dysfunction in multiple cortico-striatal circuits. The neurodegeneration has also been associated with impaired white matter integrity. This structural and functional “disconnection” in PD needs further characterization. We investigated the structural and functional organization of the PD whole brain connectome consisting of 200 nodes using diffusion tensor imaging and resting-state functional MRI, respectively. Data from 20 non-demented PD patients on dopaminergic medication and 20 matched controls were analyzed using graph theory-based methods. We focused on node strength, clustering coefficient, and local efficiency as measures of local network properties; and network modularity as a measure of information flow. PD patients showed reduced white matter connectivity in frontoparietal-striatal nodes compared to controls, but no change in modular organization of the white matter tracts. PD group also showed reduction in functional local network metrics in many nodes distributed across the connectome. There was also decreased functional modularity in the core cognitive networks including the default mode and dorsal attention networks, and sensorimotor network, as well as a lack of modular distinction in the orbitofrontal and basal ganglia nodes in the PD group compared to controls. Our results suggest that despite subtle white matter connectivity changes, the overall structural organization of the PD connectome remains robust at relatively early disease stages. However, there is a breakdown in the functional modular organization of the PD connectome. DTI and rs-fMRI investigation of the connectome in Parkinson's disease (PD) Local network properties and modularity were examined using graph theory. White matter connectivity was decreased in frontoparietal-striatal nodes in PD. Functional modularity of cognitive and motor networks was reduced in PD.
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Affiliation(s)
- Sule Tinaz
- Division of Movement Disorders, Department of Neurology, Yale School of Medicine, New Haven, CT, USA; Human Motor Control Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Peter M Lauro
- Office of the Clinical Director, National Institute of Neurologic Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Pritha Ghosh
- Office of the Clinical Director, National Institute of Neurologic Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA; Parkinson's Disease and Movement Disorders Program, Department of Neurology, George Washington University, Washington, DC, USA
| | - Codrin Lungu
- Office of the Clinical Director, National Institute of Neurologic Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Silvina G Horovitz
- Human Motor Control Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
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Gangalum RK, Bhat AM, Kohan SA, Bhat SP. Inhibition of the Expression of the Small Heat Shock Protein αB-Crystallin Inhibits Exosome Secretion in Human Retinal Pigment Epithelial Cells in Culture. J Biol Chem 2016; 291:12930-42. [PMID: 27129211 DOI: 10.1074/jbc.m115.698530] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Indexed: 01/15/2023] Open
Abstract
Exosomes carry cell type-specific molecular cargo to extracellular destinations and therefore act as lateral vectors of intercellular communication and transfer of genetic information from one cell to the other. We have shown previously that the small heat shock protein αB-crystallin (αB) is exported out of the adult human retinal pigment epithelial cells (ARPE19) packaged in exosomes. Here, we demonstrate that inhibition of the expression of αB via shRNA inhibits exosome secretion from ARPE19 cells indicating that exosomal cargo may have a role in exosome biogenesis (synthesis and/or secretion). Sucrose density gradient fractionation of the culture medium and cellular extracts suggests continued synthesis of exosomes but an inhibition of exosome secretion. In cells where αB expression was inhibited, the distribution of CD63 (LAMP3), an exosome marker, is markedly altered from the normal dispersed pattern to a stacked perinuclear presence. Interestingly, the total anti-CD63(LAMP3) immunofluorescence in the native and αB-inhibited cells remains unchanged suggesting continued exosome synthesis under conditions of impaired exosome secretion. Importantly, inhibition of the expression of αB results in a phenotype of the RPE cell that contains an increased number of vacuoles and enlarged (fused) vesicles that show increased presence of CD63(LAMP3) and LAMP1 indicating enhancement of the endolysosomal compartment. This is further corroborated by increased Rab7 labeling of this compartment (RabGTPase 7 is known to be associated with late endosome maturation). These data collectively point to a regulatory role for αB in exosome biogenesis possibly via its involvement at a branch point in the endocytic pathway that facilitates secretion of exosomes.
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Affiliation(s)
| | - Ankur M Bhat
- From the Jules Stein Eye Institute, Geffen School of Medicine
| | - Sirus A Kohan
- Brain Research Institute, UCLA, Los Angeles, California 90095
| | - Suraj P Bhat
- From the Jules Stein Eye Institute, Geffen School of Medicine, Brain Research Institute, UCLA, Los Angeles, California 90095 Molecular Biology Institute and
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