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Currim F, Tanwar R, Brown-Leung JM, Paranjape N, Liu J, Sanders LH, Doorn JA, Cannon JR. Selective dopaminergic neurotoxicity modulated by inherent cell-type specific neurobiology. Neurotoxicology 2024; 103:266-287. [PMID: 38964509 PMCID: PMC11288778 DOI: 10.1016/j.neuro.2024.06.016] [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: 02/18/2024] [Revised: 06/27/2024] [Accepted: 06/28/2024] [Indexed: 07/06/2024]
Abstract
Parkinson's disease (PD) is a debilitating neurodegenerative disease affecting millions of individuals worldwide. Hallmark features of PD pathology are the formation of Lewy bodies in neuromelanin-containing dopaminergic (DAergic) neurons of the substantia nigra pars compacta (SNpc), and the subsequent irreversible death of these neurons. Although genetic risk factors have been identified, around 90 % of PD cases are sporadic and likely caused by environmental exposures and gene-environment interaction. Mechanistic studies have identified a variety of chemical PD risk factors. PD neuropathology occurs throughout the brain and peripheral nervous system, but it is the loss of DAergic neurons in the SNpc that produce many of the cardinal motor symptoms. Toxicology studies have found specifically the DAergic neuron population of the SNpc exhibit heightened sensitivity to highly variable chemical insults (both in terms of chemical structure and mechanism of neurotoxic action). Thus, it has become clear that the inherent neurobiology of nigral DAergic neurons likely underlies much of this neurotoxic response to broad insults. This review focuses on inherent neurobiology of nigral DAergic neurons and how such neurobiology impacts the primary mechanism of neurotoxicity. While interactions with a variety of other cell types are important in disease pathogenesis, understanding how inherent DAergic biology contributes to selective sensitivity and primary mechanisms of neurotoxicity is critical to advancing the field. Specifically, key biological features of DAergic neurons that increase neurotoxicant susceptibility.
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Affiliation(s)
- Fatema Currim
- School of Health Sciences, Purdue University, West Lafayette, IN 47901, USA; Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN 47901, USA
| | - Reeya Tanwar
- School of Health Sciences, Purdue University, West Lafayette, IN 47901, USA; Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN 47901, USA
| | - Josephine M Brown-Leung
- School of Health Sciences, Purdue University, West Lafayette, IN 47901, USA; Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN 47901, USA
| | - Neha Paranjape
- Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, Iowa City, IA 52242, USA
| | - Jennifer Liu
- Departments of Neurology and Pathology, Duke University School of Medicine, Durham, NC 27710, USA; Duke Center for Neurodegeneration and Neurotherapeutics, Duke University School of Medicine, Durham, NC 27710, USA
| | - Laurie H Sanders
- Departments of Neurology and Pathology, Duke University School of Medicine, Durham, NC 27710, USA; Duke Center for Neurodegeneration and Neurotherapeutics, Duke University School of Medicine, Durham, NC 27710, USA
| | - Jonathan A Doorn
- Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, University of Iowa, Iowa City, IA 52242, USA
| | - Jason R Cannon
- School of Health Sciences, Purdue University, West Lafayette, IN 47901, USA; Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN 47901, USA.
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Huenchuguala S, Segura-Aguilar J. Targets to Search for New Pharmacological Treatment in Idiopathic Parkinson's Disease According to the Single-Neuron Degeneration Model. Biomolecules 2024; 14:673. [PMID: 38927076 PMCID: PMC11201619 DOI: 10.3390/biom14060673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Revised: 05/28/2024] [Accepted: 05/29/2024] [Indexed: 06/28/2024] Open
Abstract
One of the biggest problems in the treatment of idiopathic Parkinson's disease is the lack of new drugs that slow its progression. L-Dopa remains the star drug in the treatment of this disease, although it induces severe side effects. The failure of clinical studies with new drugs depends on the use of preclinical models based on neurotoxins that do not represent what happens in the disease since they induce rapid and expansive neurodegeneration. We have recently proposed a single-neuron degeneration model for idiopathic Parkinson's disease that requires years to accumulate enough lost neurons for the onset of motor symptoms. This single-neuron degeneration model is based on the excessive formation of aminochrome during neuromelanin synthesis that surpass the neuroprotective action of the enzymes DT-diaphorase and glutathione transferase M2-2, which prevent the neurotoxic effects of aminochrome. Although the neurotoxic effects of aminochrome do not have an expansive effect, a stereotaxic injection of this endogenous neurotoxin cannot be used to generate a preclinical model in an animal. Therefore, the aim of this review is to evaluate the strategies for pharmacologically increasing the expression of DT diaphorase and GSTM2-2 and molecules that induce the expression of vesicular monoamine transporter 2, such as pramipexole.
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Affiliation(s)
- Sandro Huenchuguala
- Escuela de Tecnología Médica, Facultad de Salud, Universidad Santo Tomás, Santiago 8370003, Chile;
| | - Juan Segura-Aguilar
- Molecular & Clinical Pharmacology, ICBM, Faculty of Medicine, University of Chile, Santiago 8330111, Chile
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Kampmann M. Molecular and cellular mechanisms of selective vulnerability in neurodegenerative diseases. Nat Rev Neurosci 2024; 25:351-371. [PMID: 38575768 DOI: 10.1038/s41583-024-00806-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/01/2024] [Indexed: 04/06/2024]
Abstract
The selective vulnerability of specific neuronal subtypes is a hallmark of neurodegenerative diseases. In this Review, I summarize our current understanding of the brain regions and cell types that are selectively vulnerable in different neurodegenerative diseases and describe the proposed underlying cell-autonomous and non-cell-autonomous mechanisms. I highlight how recent methodological innovations - including single-cell transcriptomics, CRISPR-based screens and human cell-based models of disease - are enabling new breakthroughs in our understanding of selective vulnerability. An understanding of the molecular mechanisms that determine selective vulnerability and resilience would shed light on the key processes that drive neurodegeneration and point to potential therapeutic strategies to protect vulnerable cell populations.
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Affiliation(s)
- Martin Kampmann
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA, USA.
- Institute for Neurodegenerative Diseases, University of California, San Francisco, San Francisco, CA, USA.
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Huenchuguala S, Segura-Aguilar J. On the Role of Iron in Idiopathic Parkinson's Disease. Biomedicines 2023; 11:3094. [PMID: 38002094 PMCID: PMC10669582 DOI: 10.3390/biomedicines11113094] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Revised: 11/04/2023] [Accepted: 11/17/2023] [Indexed: 11/26/2023] Open
Abstract
The transition metal characteristics of iron allow it to play a fundamental role in several essential aspects of human life such as the transport of oxygen through hemoglobin or the transport of electrons in the mitochondrial respiratory chain coupled to the synthesis of ATP. However, an excess or deficiency of iron is related to certain pathologies. The maintenance of iron homeostasis is essential to avoid certain pathologies related to iron excess or deficiency. The existence of iron deposits in postmortem tissues of Parkinson's patients has been interpreted as evidence that iron plays a fundamental role in the degenerative process of the nigrostriatal system in this disease. The use of iron chelators has been successful in the treatment of diseases such as transfusion-dependent thalassemia and pantothenate kinase-associated neurodegeneration. However, a clinical study with the iron chelator deferiprone in patients with Parkinson's disease has not shown positive effects but rather worsened clinical symptoms. This suggests that iron may not play a role in the degenerative process of Parkinson's disease.
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Affiliation(s)
- Sandro Huenchuguala
- Escuela de Tecnología Médica, Facultad de Salud, Universidad Santo Tomás, Santiago 8370003, Chile
| | - Juan Segura-Aguilar
- Molecular & Clinical Pharmacology, Institute of Biomedical Sciences (ICBM), Faculty of Medicine, University of Chile, Santiago 8380453, Chile
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Huenchuguala S, Segura-Aguilar J. Why are neuromelanin-containing dopaminergic neurons lost in idiopathic Parkinson's disease? Cell Mol Life Sci 2023; 80:281. [PMID: 37688601 PMCID: PMC11071948 DOI: 10.1007/s00018-023-04880-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 05/31/2023] [Accepted: 07/16/2023] [Indexed: 09/11/2023]
Affiliation(s)
- Sandro Huenchuguala
- Escuela de Tecnología Médica, Facultad de Salud, Universidad Santo Tomás, Los Carreras 753, Osorno, Chile
| | - Juan Segura-Aguilar
- Molecular and Clinical Pharmacology, ICBM, Faculty of Medicine, University of Chile, Santiago, Chile.
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Zhang D, Yao J, Sun J, Wang J, Chen L, He H, Wu T. Iron accumulation in the ventral tegmental area in Parkinson's disease. Front Aging Neurosci 2023; 15:1187684. [PMID: 37448687 PMCID: PMC10338054 DOI: 10.3389/fnagi.2023.1187684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Accepted: 06/09/2023] [Indexed: 07/15/2023] Open
Abstract
Introduction The ventral tegmental area (VTA) is less affected compared to substantia nigra pars compacta (SNc) in Parkinson's disease (PD). This study aimed to quantitatively evaluate iron content in the VTA across different stages of PD in order to help explain the selective loss of dopamine neurons in PD. Methods Quantitative susceptibility mapping (QSM) data were obtained from 101 PD patients, 35 idiopathic rapid eye movement sleep behavior disorder (RBD) patients, and 62 healthy controls (HCs). The mean QSM values in the VTA and SNc were calculated and compared among the groups. Results Both RBD and PD patients had increased iron values in the bilateral SNc compared with HCs. RBD and PD patients in the Hoehn-Yahr (H & Y) stage 1 did not show elevated iron values in the VTA, while PD patients with more than 1.5 H & Y staging had increased iron values in bilateral VTA compared to HCs. Discussion This study shows that there is no increased iron accumulation in the VTA during the prodromal and early clinical stages of PD, but iron deposition increases significantly as the disease becomes more severe.
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Affiliation(s)
- Dongling Zhang
- Center for Movement Disorders, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
- China National Clinical Research Center for Neurological Diseases, Beijing, China
- Parkinson's Disease Center, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
| | - Junye Yao
- Center for Brain Imaging Science and Technology, College of Biomedical Engineering and Instrument Science, Zhejiang University, Hangzhou, Zhejiang, China
| | - Junyan Sun
- Center for Movement Disorders, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
- China National Clinical Research Center for Neurological Diseases, Beijing, China
- Parkinson's Disease Center, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
| | - Junling Wang
- Center for Movement Disorders, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
- China National Clinical Research Center for Neurological Diseases, Beijing, China
- Parkinson's Disease Center, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
| | - Lili Chen
- Center for Movement Disorders, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
- China National Clinical Research Center for Neurological Diseases, Beijing, China
- Parkinson's Disease Center, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
| | - Hongjian He
- Center for Brain Imaging Science and Technology, College of Biomedical Engineering and Instrument Science, Zhejiang University, Hangzhou, Zhejiang, China
- School of Physics, Zhejiang University, Hangzhou, Zhejiang, China
| | - Tao Wu
- Center for Movement Disorders, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
- China National Clinical Research Center for Neurological Diseases, Beijing, China
- Parkinson's Disease Center, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
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Pifl C, Reither H, Attems J, Zecca L. Dopamine and vesicular monoamine transport loss supports incidental Lewy body disease as preclinical idiopathic Parkinson. NPJ Parkinsons Dis 2023; 9:89. [PMID: 37322038 DOI: 10.1038/s41531-023-00514-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Accepted: 04/27/2023] [Indexed: 06/17/2023] Open
Abstract
Incidental Lewy body disease (ILBD) is a neuropathological diagnosis of brains with Lewy bodies without clinical neuropsychiatric symptoms. Dopaminergic deficits suggest a relationship to preclinical Parkinson's disease (PD). We now report a subregional pattern of striatal dopamine loss in ILBD cases, with dopamine found significantly decreased in the putamen (-52%) and only to a lower extent in the caudate (-38%, not statistically significant); this is similar to the pattern in idiopathic PD in various neurochemical and in vivo imaging studies. We aimed to find out if our recently reported impaired storage of dopamine in striatal synaptic vesicles prepared from striatal tissue of cases with idiopathic PD might be an early or even causative event. We undertook parallel measurements of [3H]dopamine uptake and vesicular monoamine transporter (VMAT)2 binding sites by the specific label [3H]dihydrotetrabenazine on vesicular preparation from caudate and putamen in ILBD. Neither specific uptake of dopamine and binding of [3H]dihydrotetrabenazine, nor mean values of the calculated ratios of dopamine uptake and VMAT2 binding, a measure of uptake rate per transport site, were significantly different between ILBD and controls. ATP-dependence of [3H]dopamine uptake revealed significantly higher rates in putamen than in caudate at saturating concentrations of ATP in controls, a subregional difference lost in ILBD. Our findings support a loss of the normally higher VMAT2 activity in putamen as a contributing factor to the higher susceptibility of the putamen to dopamine depletion in idiopathic PD. Moreover, we suggest ILBD postmortem tissue as a valuable source for testing hypotheses on processes in idiopathic PD.
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Affiliation(s)
- Christian Pifl
- Center for Brain Research, Medical University of Vienna, Vienna, Austria.
| | - Harald Reither
- Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Johannes Attems
- Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne, UK
| | - Luigi Zecca
- Institute of Biomedical Technologies, National Research Council of Italy, Segrate, Milan, Italy
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Mitra R, Premraj L, Khoo TK. Neuromelanin: Its role in the pathogenesis of idiopathic Parkinson's disease and potential as a therapeutic target. Parkinsonism Relat Disord 2023:105448. [PMID: 37236833 DOI: 10.1016/j.parkreldis.2023.105448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2023] [Revised: 05/10/2023] [Accepted: 05/18/2023] [Indexed: 05/28/2023]
Abstract
Parkinson's disease is an increasingly prevalent condition that involves the marked loss of dopaminergic neurons in the substantia nigra pars compacta. These neurons pigmented with neuromelanin along with other regions of the brain are almost exclusively victims of neurodegeneration in the disease. The link between neuromelanin and Parkinson's disease has been widely studied for decades. While many studies have outlined the pigment's neuroprotective function as a potent free radical scavenger, antioxidant, and ion-chelator, it has also been observed to play a role in cell death due to mitochondrial dysfunction and oxidative stress, especially in the parkinsonian disease state. This is due to the damaging effects of neuromelanin precursors, neuromelanin-related ion dysregulation and intra- and extraneuronal neuromelanin accumulation. Current and emerging therapeutic endeavours guided by these pathological processes may include antioxidant therapy, proteostasis enhancement, ion chelation and neuromelanin-targeted immunotherapy to prevent the accumulation, formation and effects of neuromelanin and oxidative neuromelanin precursors. Some of these therapeutic strategies are already in nascent stages, while others have produced mixed results in clinical trials. This review aims to provide an update on how neuromelanin and neuromelanin-related substances may be linked to the pathogenesis of Parkinson's disease and how future therapeutic strategies may be able to hamper or prevent neuromelanin-related pathological processes and ultimately modify disease progression in Parkinson's.
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Affiliation(s)
- Ritoban Mitra
- College of Medicine and Public Health, Flinders University, South Australia, Australia.
| | - Lavienraj Premraj
- School of Medicine & Dentistry, Griffith University, Queensland, Australia
| | - Tien K Khoo
- School of Medicine & Dentistry, Griffith University, Queensland, Australia; Graduate School of Medicine, University of Wollongong, New South Wales, Australia
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Huang Q, Chen C, Chen W, Cai C, Xing H, Li J, Li M, Ma S. Cell type- and region-specific translatomes in an MPTP mouse model of Parkinson's disease. Neurobiol Dis 2023; 180:106105. [PMID: 36977454 DOI: 10.1016/j.nbd.2023.106105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 03/16/2023] [Accepted: 03/24/2023] [Indexed: 03/28/2023] Open
Abstract
Parkinson's disease (PD) is the most common neurodegenerative movement disorder, characterized by the progressive loss of nigrostriatal dopaminergic neurons (DANs), involving the dysregulation of both neurons and glial cells. Cell type- and region-specific gene expression profiles can provide an effective source for revealing the mechanisms of PD. In this study, we adopted the RiboTag approach to obtain cell type (DAN, microglia, astrocytes)- and brain region (substantia nigra, caudate-putamen)-specific translatomes at an early stage in an MPTP-induced mouse model of PD. Through DAN-specific translatome analysis, the glycosphingolipid biosynthetic process was identified as a significantly downregulated pathway in the MPTP-treated mice. ST8Sia6, a key downregulated gene related to glycosphingolipid biosynthesis, was confirmed to be downregulated in nigral DANs from postmortem brains of patients with PD. Specific expression of ST8Sia6 in DANs exerts anti-inflammatory and neuroprotective effects in MPTP-treated mice. Through cell type (microglia vs. astrocyte) and brain region (substantia nigra vs. caudate-putamen) comparisons, nigral microglia showed the most intense immune responses. Microglia and astrocytes in the substantia nigra showed similar levels of activation in interferon-related pathways and interferon gamma (IFNG) was identified as the top upstream regulator in both cell types. This work highlights that the glycosphingolipid metabolism pathway in the DAN is involved in neuroinflammation and neurodegeneration in an MPTP mouse model of PD and provides a new data source for elucidating the pathogenesis of PD.
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Gonzalez-Sepulveda M, Compte J, Cuadros T, Nicolau A, Guillard-Sirieix C, Peñuelas N, Lorente-Picon M, Parent A, Romero-Giménez J, Cladera-Sastre JM, Laguna A, Vila M. In vivo reduction of age-dependent neuromelanin accumulation mitigates features of Parkinson's disease. Brain 2023; 146:1040-1052. [PMID: 36717986 PMCID: PMC9976971 DOI: 10.1093/brain/awac445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 10/10/2022] [Accepted: 11/08/2022] [Indexed: 02/01/2023] Open
Abstract
Humans accumulate with age the dark-brown pigment neuromelanin inside specific neuronal groups. Neurons with the highest neuromelanin levels are particularly susceptible to degeneration in Parkinson's disease, especially dopaminergic neurons of the substantia nigra, the loss of which leads to characteristic motor Parkinson's disease symptoms. In contrast to humans, neuromelanin does not appear spontaneously in most animals, including rodents, and Parkinson's disease is an exclusively human condition. Using humanized neuromelanin-producing rodents, we recently found that neuromelanin can trigger Parkinson's disease pathology when accumulated above a specific pathogenic threshold. Here, by taking advantage of this newly developed animal model, we assessed whether the intracellular build-up of neuromelanin that occurs with age can be slowed down in vivo to prevent or attenuate Parkinson's disease. Because neuromelanin derives from the oxidation of free cytosolic dopamine, we enhanced dopamine vesicular encapsulation in the substantia nigra of neuromelanin-producing rats by viral vector-mediated overexpression of vesicular monoamine transporter 2 (VMAT2). This strategy reduced the formation of potentially toxic oxidized dopamine species that can convert into neuromelanin and maintained intracellular neuromelanin levels below their pathogenic threshold. Decreased neuromelanin production was associated with an attenuation of Lewy body-like inclusion formation and a long-term preservation of dopamine homeostasis, nigrostriatal neuronal integrity and motor function in these animals. Our results demonstrate the feasibility and therapeutic potential of modulating age-dependent intracellular neuromelanin production in vivo, thereby opening an unexplored path for the treatment of Parkinson's disease and, in a broader sense, brain ageing.
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Affiliation(s)
| | | | - Thais Cuadros
- Neurodegenerative Diseases Research Group, Vall d’Hebron Research Institute (VHIR)-Center for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED), 08035 Barcelona, Spain,Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
| | - Alba Nicolau
- Neurodegenerative Diseases Research Group, Vall d’Hebron Research Institute (VHIR)-Center for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED), 08035 Barcelona, Spain,Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
| | - Camille Guillard-Sirieix
- Neurodegenerative Diseases Research Group, Vall d’Hebron Research Institute (VHIR)-Center for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED), 08035 Barcelona, Spain,Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
| | - Núria Peñuelas
- Neurodegenerative Diseases Research Group, Vall d’Hebron Research Institute (VHIR)-Center for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED), 08035 Barcelona, Spain,Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
| | - Marina Lorente-Picon
- Neurodegenerative Diseases Research Group, Vall d’Hebron Research Institute (VHIR)-Center for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED), 08035 Barcelona, Spain,Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
| | - Annabelle Parent
- Neurodegenerative Diseases Research Group, Vall d’Hebron Research Institute (VHIR)-Center for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED), 08035 Barcelona, Spain,Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
| | - Jordi Romero-Giménez
- Neurodegenerative Diseases Research Group, Vall d’Hebron Research Institute (VHIR)-Center for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED), 08035 Barcelona, Spain
| | - Joana M Cladera-Sastre
- Neurodegenerative Diseases Research Group, Vall d’Hebron Research Institute (VHIR)-Center for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED), 08035 Barcelona, Spain,Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
| | - Ariadna Laguna
- Neurodegenerative Diseases Research Group, Vall d’Hebron Research Institute (VHIR)-Center for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED), 08035 Barcelona, Spain,Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA,Institut de Neurociències (INc-UAB), Autonomous University of Barcelona, 08193 Bellaterra, Barcelona, Spain
| | - Miquel Vila
- Correspondence to: Miquel Vila Vall d’Hebron Research Institute (VHIR), Neurodegenerative Diseases Passeig Vall d’Hebron, 119-129 08035 Barcelona, Spain E-mail:
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Zucca FA, Capucciati A, Bellei C, Sarna M, Sarna T, Monzani E, Casella L, Zecca L. Neuromelanins in brain aging and Parkinson's disease: synthesis, structure, neuroinflammatory, and neurodegenerative role. IUBMB Life 2023; 75:55-65. [PMID: 35689524 PMCID: PMC10084223 DOI: 10.1002/iub.2654] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 05/10/2022] [Indexed: 12/29/2022]
Abstract
Neuromelanins are compounds accumulating in neurons of human and animal brain during aging, with neurons of substantia nigra and locus coeruleus having the highest levels of neuromelanins. These compounds have melanic, lipid, peptide, and inorganic components and are contained inside special autolysosomes. Neuromelanins can participate in neuroprotective or toxic processes occurring in Parkinson's disease according to cellular environment. Their synthesis depends on the concentration of cytosolic catechols and is a protective process since it prevents the toxic accumulation of catechols-derived reactive compounds. Neuromelanins can be neuroprotective also by binding reactive/toxic metals to produce stable and non-toxic complexes. Extraneuronal neuromelanin released by dying dopamine neurons in Parkinson's disease activates microglia which generate reactive oxygen species, reactive nitrogen species, and proinflammatory molecules, thus producing still neuroinflammation and neuronal death. Synthetic neuromelanins have been prepared with melanic, protein structure, and metal content closely mimicking the natural brain pigment, and these models are also able to activate microglia. Neuromelanins have different structure, synthesis, cellular/subcellular distribution, and role than melanins of hair, skin, and other tissues. The main common aspect between brain neuromelanin and peripheral melanin is the presence of eumelanin and/or pheomelanin moieties in their structure.
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Affiliation(s)
- Fabio A Zucca
- Institute of Biomedical Technologies, National Research Council of Italy, Segrate (Milan), Italy
| | | | - Chiara Bellei
- Institute of Biomedical Technologies, National Research Council of Italy, Segrate (Milan), Italy
| | - Michał Sarna
- Department of Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland
| | - Tadeusz Sarna
- Department of Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland
| | - Enrico Monzani
- Department of Chemistry, University of Pavia, Pavia, Italy
| | - Luigi Casella
- Department of Chemistry, University of Pavia, Pavia, Italy
| | - Luigi Zecca
- Institute of Biomedical Technologies, National Research Council of Italy, Segrate (Milan), Italy
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The Proteome of Neuromelanin Granules in Dementia with Lewy Bodies. Cells 2022; 11:cells11223538. [PMID: 36428966 PMCID: PMC9688080 DOI: 10.3390/cells11223538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 10/28/2022] [Accepted: 11/02/2022] [Indexed: 11/12/2022] Open
Abstract
Neuromelanin granules (NMGs) are organelle-like structures present in the human substantia nigra pars compacta. In addition to neuromelanin, NMGs contain proteins, lipids and metals. As NMG-containing dopaminergic neurons are preferentially lost in Parkinson's disease and dementia with Lewy bodies (DLB), it is assumed that NMGs may play a role in neurodegenerative processes. Until now, this role is not completely understood and needs further investigation. We therefore set up an exploratory proteomic study to identify differences in the proteomic profile of NMGs from DLB patients (n = 5) compared to healthy controls (CTRL, n = 5). We applied a laser microdissection and mass-spectrometry-based approach, in which we used targeted mass spectrometric experiments for validation. In NMG-surrounding (SNSurr.) tissue of DLB patients, we found evidence for ongoing oxidative damage and an impairment of protein degradation. As a potentially disease-related mechanism, we found α-synuclein and protein S100A9 to be enriched in NMGs of DLB cases, while the abundance of several ribosomal proteins was significantly decreased. As S100A9 is known to be able to enhance the formation of toxic α-synuclein fibrils, this finding points towards an involvement of NMGs in pathogenesis, however the exact role of NMGs as either neuroprotective or neurotoxic needs to be further investigated. Nevertheless, our study provides evidence for an impairment of protein degradation, ongoing oxidative damage and accumulation of potentially neurotoxic protein aggregates to be central mechanisms of neurodegeneration in DLB.
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13
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Interactions of dopamine, iron, and alpha-synuclein linked to dopaminergic neuron vulnerability in Parkinson's disease and neurodegeneration with brain iron accumulation disorders. Neurobiol Dis 2022; 175:105920. [DOI: 10.1016/j.nbd.2022.105920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 10/21/2022] [Accepted: 11/04/2022] [Indexed: 11/08/2022] Open
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14
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Carving the senescent phenotype by the chemical reactivity of catecholamines: An integrative review. Ageing Res Rev 2022; 75:101570. [PMID: 35051644 DOI: 10.1016/j.arr.2022.101570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 01/11/2022] [Accepted: 01/15/2022] [Indexed: 11/21/2022]
Abstract
Macromolecules damaged by covalent modifications produced by chemically reactive metabolites accumulate in the slowly renewable components of living bodies and compromise their functions. Among such metabolites, catecholamines (CA) are unique, compared with the ubiquitous oxygen, ROS, glucose and methylglyoxal, in that their high chemical reactivity is confined to a limited set of cell types, including the dopaminergic and noradrenergic neurons and their direct targets, which suffer from CA propensities for autoxidation yielding toxic quinones, and for Pictet-Spengler reactions with carbonyl-containing compounds, which yield mitochondrial toxins. The functions progressively compromised because of that include motor performance, cognition, reward-driven behaviors, emotional tuning, and the neuroendocrine control of reproduction. The phenotypic manifestations of the resulting disorders culminate in such conditions as Parkinson's and Alzheimer's diseases, hypertension, sarcopenia, and menopause. The reasons to suspect that CA play some special role in aging accumulated since early 1970-ies. Published reviews address the role of CA hazardousness in the development of specific aging-associated diseases. The present integrative review explores how the bizarre discrepancy between CA hazardousness and biological importance could have emerged in evolution, how much does the chemical reactivity of CA contribute to the senescent phenotype in mammals, and what can be done with it.
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15
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Neuroprotection against Aminochrome Neurotoxicity: Glutathione Transferase M2-2 and DT-Diaphorase. Antioxidants (Basel) 2022; 11:antiox11020296. [PMID: 35204179 PMCID: PMC8868244 DOI: 10.3390/antiox11020296] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 01/20/2022] [Accepted: 01/24/2022] [Indexed: 02/04/2023] Open
Abstract
Glutathione is an important antioxidant that plays a crucial role in the cellular protection against oxidative stress and detoxification of electrophilic mutagens, and carcinogens. Glutathione transferases are enzymes catalyzing glutathione-dependent reactions that lead to inactivation and conjugation of toxic compounds, processes followed by subsequent excretion of the detoxified products. Degeneration and loss of neuromelanin-containing dopaminergic neurons in the nigrostriatal neurons generally involves oxidative stress, neuroinflammation, alpha-synuclein aggregation to neurotoxic oligomers, mitochondrial dysfunction, protein degradation dysfunction, and endoplasmic reticulum stress. However, it is still unclear what triggers these neurodegenerative processes. It has been reported that aminochrome may elicit all of these mechanisms and, interestingly, aminochrome is formed inside neuromelanin-containing dopaminergic neurons during neuromelanin synthesis. Aminochrome is a neurotoxic ortho-quinone formed in neuromelanin synthesis. However, it seems paradoxical that the neurotoxin aminochrome is generated during neuromelanin synthesis, even though healthy seniors have these neurons intact when they die. The explanation of this paradox is the existence of protective tools against aminochrome neurotoxicity composed of the enzymes DT-diaphorase, expressed in these neurons, and glutathione transferase M2-2, expressed in astrocytes. Recently, it has been reported that dopaminergic neurons can be protected by glutathione transferase M2-2 from astrocytes, which secrete exosomes containing the protective enzyme.
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16
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Influences of dopaminergic system dysfunction on late-life depression. Mol Psychiatry 2022; 27:180-191. [PMID: 34404915 PMCID: PMC8850529 DOI: 10.1038/s41380-021-01265-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 07/28/2021] [Accepted: 08/04/2021] [Indexed: 12/15/2022]
Abstract
Deficits in cognition, reward processing, and motor function are clinical features relevant to both aging and depression. Individuals with late-life depression often show impairment across these domains, all of which are moderated by the functioning of dopaminergic circuits. As dopaminergic function declines with normal aging and increased inflammatory burden, the role of dopamine may be particularly salient for late-life depression. We review the literature examining the role of dopamine in the pathogenesis of depression, as well as how dopamine function changes with aging and is influenced by inflammation. Applying a Research Domain Criteria (RDoC) Initiative perspective, we then review work examining how dopaminergic signaling affects these domains, specifically focusing on Cognitive, Positive Valence, and Sensorimotor Systems. We propose a unified model incorporating the effects of aging and low-grade inflammation on dopaminergic functioning, with a resulting negative effect on cognition, reward processing, and motor function. Interplay between these systems may influence development of a depressive phenotype, with an initial deficit in one domain reinforcing decline in others. This model extends RDoC concepts into late-life depression while also providing opportunities for novel and personalized interventions.
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17
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Ueno F, Iwata Y, Nakajima S, Caravaggio F, Rubio JM, Horga G, Cassidy CM, Torres-Carmona E, de Luca V, Tsugawa S, Honda S, Moriguchi S, Noda Y, Gerretsen P, Graff-Guerrero A. Neuromelanin accumulation in patients with schizophrenia: A systematic review and meta-analysis. Neurosci Biobehav Rev 2021; 132:1205-1213. [PMID: 34718049 PMCID: PMC9059704 DOI: 10.1016/j.neubiorev.2021.10.028] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 10/21/2021] [Accepted: 10/24/2021] [Indexed: 11/25/2022]
Abstract
Although schizophrenia is associated with increased presynaptic dopamine function in the striatum, it remains unclear if neuromelanin levels, which are thought to serve as a biomarker for midbrain dopamine neuron function, are increased in patients with schizophrenia. We conducted a systematic review and meta-analysis of magnetic resonance imaging (MRI) and postmortem studies comparing neuromelanin (NM) levels between patients with schizophrenia and healthy controls (HCs). Standard mean differences were calculated to assess group differences in NM accumulation levels between patients with schizophrenia and HCs. This study included 7 articles in total. Five studies employed NM-sensitive MRI (NM-MRI) and two were postmortem brain studies. The patient group (n = 163) showed higher NM levels in the substantia nigra (SN) than HCs (n = 228) in both the analysis of the seven studies and the subgroup analysis of the 5 NM-MRI studies. This analysis suggest increased NM levels in the SN may be a potential biomarker for stratifying schizophrenia, warranting further research that accounts for the heterogeneity of this disorder.
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Affiliation(s)
- Fumihiko Ueno
- Brain Health Imaging Centre, Centre for Addiction and Mental Health (CAMH), Toronto, Ontario, Canada; Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada; Department of Neuropsychiatry, Keio University School of Medicine, Tokyo, Japan
| | - Yusuke Iwata
- Department of Neuropsychiatry, University of Yamanashi, Faculty of Medicine, Yamanashi, Japan
| | - Shinichiro Nakajima
- Brain Health Imaging Centre, Centre for Addiction and Mental Health (CAMH), Toronto, Ontario, Canada; Department of Neuropsychiatry, Keio University School of Medicine, Tokyo, Japan.
| | - Fernando Caravaggio
- Brain Health Imaging Centre, Centre for Addiction and Mental Health (CAMH), Toronto, Ontario, Canada; Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
| | - Jose M Rubio
- Barbara and Donald Zucker School of Medicine at Hofstra University - Northwell Health, Hempstead, NY, USA; Institute of Behavioral Science, Feinstein Institutes of Medical Research, Manhasset, NY, USA; Division of Psychiatry Research, Zucker Hillside Hospital, Glen Oaks, NY, USA
| | - Guillermo Horga
- Department of Psychiatry, Columbia University, New York, NY, USA; Division of Translational Imaging, New York State Psychiatric Institute, New York, NY, USA
| | - Clifford M Cassidy
- The Royal's Institute of Mental Health Research Affiliated with the University of Ottawa, Ottawa, Ontario, Canada
| | - Edgardo Torres-Carmona
- Brain Health Imaging Centre, Centre for Addiction and Mental Health (CAMH), Toronto, Ontario, Canada; Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
| | - Vincenzo de Luca
- Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada; Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada; Campbell Family Mental Health Research Institute, CAMH, Toronto, Ontario, Canada
| | - Sakiko Tsugawa
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo, Japan
| | - Shiori Honda
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo, Japan
| | - Sho Moriguchi
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo, Japan
| | - Yoshihiro Noda
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo, Japan
| | - Philip Gerretsen
- Brain Health Imaging Centre, Centre for Addiction and Mental Health (CAMH), Toronto, Ontario, Canada; Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada; Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada; Campbell Family Mental Health Research Institute, CAMH, Toronto, Ontario, Canada
| | - Ariel Graff-Guerrero
- Brain Health Imaging Centre, Centre for Addiction and Mental Health (CAMH), Toronto, Ontario, Canada; Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada; Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada; Campbell Family Mental Health Research Institute, CAMH, Toronto, Ontario, Canada.
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18
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Toxic Feedback Loop Involving Iron, Reactive Oxygen Species, α-Synuclein and Neuromelanin in Parkinson's Disease and Intervention with Turmeric. Mol Neurobiol 2021; 58:5920-5936. [PMID: 34426907 DOI: 10.1007/s12035-021-02516-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 08/03/2021] [Indexed: 12/20/2022]
Abstract
Parkinson's disease (PD) is a movement disorder associated with severe loss of mainly dopaminergic neurons in the substantia nigra. Pathological hallmarks include Lewy bodies, and loss of neuromelanin, due to degeneration of neuromelanin-containing dopaminergic neurons. Despite being described over 200 years ago, the etiology of PD remains unknown. Here, we highlight the roles of reactive oxygen species (ROS), iron, alpha synuclein (α-syn) and neuromelanin in a toxic feedback loop culminating in neuronal death and spread of the disease. Dopaminergic neurons are particularly vulnerable due to decreased antioxidant concentration with aging, constant exposure to ROS and presence of neurotoxic compounds (e.g. ortho-quinones). ROS and iron increase each other's levels, creating a state of oxidative stress. α-Syn aggregation is influenced by ROS and iron but also increases ROS and iron via its induced mitochondrial dysfunction and ferric-reductase activity. Neuromelanin's binding affinity is affected by increased ROS and iron. Furthermore, during neuronal death, neuromelanin is degraded in the extracellular space, releasing its bound toxins. This cycle of events continues to neighboring neurons in the form of a toxic loop, causing PD pathology. The increase in ROS and iron may be an important target for therapies to disrupt this toxic loop, and therefore diets rich in certain 'nutraceuticals' may be beneficial. Turmeric is an attractive candidate, as it is known to have anti-oxidant and iron chelating properties. More studies are needed to test this theory and if validated, this would be a step towards development of lifestyle-based therapeutic modalities to complement existing PD treatments.
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19
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Gasiorowska A, Wydrych M, Drapich P, Zadrozny M, Steczkowska M, Niewiadomski W, Niewiadomska G. The Biology and Pathobiology of Glutamatergic, Cholinergic, and Dopaminergic Signaling in the Aging Brain. Front Aging Neurosci 2021; 13:654931. [PMID: 34326765 PMCID: PMC8315271 DOI: 10.3389/fnagi.2021.654931] [Citation(s) in RCA: 64] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Accepted: 06/14/2021] [Indexed: 12/12/2022] Open
Abstract
The elderly population is growing worldwide, with important health and socioeconomic implications. Clinical and experimental studies on aging have uncovered numerous changes in the brain, such as decreased neurogenesis, increased synaptic defects, greater metabolic stress, and enhanced inflammation. These changes are associated with cognitive decline and neurobehavioral deficits. Although aging is not a disease, it is a significant risk factor for functional worsening, affective impairment, disease exaggeration, dementia, and general disease susceptibility. Conversely, life events related to mental stress and trauma can also lead to accelerated age-associated disorders and dementia. Here, we review human studies and studies on mice and rats, such as those modeling human neurodegenerative diseases, that have helped elucidate (1) the dynamics and mechanisms underlying the biological and pathological aging of the main projecting systems in the brain (glutamatergic, cholinergic, and dopaminergic) and (2) the effect of defective glutamatergic, cholinergic, and dopaminergic projection on disabilities associated with aging and neurodegenerative disorders, such as Alzheimer's and Parkinson's diseases. Detailed knowledge of the mechanisms of age-related diseases can be an important element in the development of effective ways of treatment. In this context, we briefly analyze which adverse changes associated with neurodegenerative diseases in the cholinergic, glutaminergic and dopaminergic systems could be targeted by therapeutic strategies developed as a result of our better understanding of these damaging mechanisms.
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Affiliation(s)
- Anna Gasiorowska
- Mossakowski Medical Research Institute, Polish Academy of Sciences, Warsaw, Poland
| | - Malgorzata Wydrych
- Mossakowski Medical Research Institute, Polish Academy of Sciences, Warsaw, Poland
| | - Patrycja Drapich
- Mossakowski Medical Research Institute, Polish Academy of Sciences, Warsaw, Poland
| | - Maciej Zadrozny
- Mossakowski Medical Research Institute, Polish Academy of Sciences, Warsaw, Poland
| | - Marta Steczkowska
- Mossakowski Medical Research Institute, Polish Academy of Sciences, Warsaw, Poland
| | - Wiktor Niewiadomski
- Mossakowski Medical Research Institute, Polish Academy of Sciences, Warsaw, Poland
| | - Grazyna Niewiadomska
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
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20
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Chen APF, Chen L, Kim TA, Xiong Q. Integrating the Roles of Midbrain Dopamine Circuits in Behavior and Neuropsychiatric Disease. Biomedicines 2021; 9:biomedicines9060647. [PMID: 34200134 PMCID: PMC8228225 DOI: 10.3390/biomedicines9060647] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 06/01/2021] [Accepted: 06/03/2021] [Indexed: 01/11/2023] Open
Abstract
Dopamine (DA) is a behaviorally and clinically diverse neuromodulator that controls CNS function. DA plays major roles in many behaviors including locomotion, learning, habit formation, perception, and memory processing. Reflecting this, DA dysregulation produces a wide variety of cognitive symptoms seen in neuropsychiatric diseases such as Parkinson’s, Schizophrenia, addiction, and Alzheimer’s disease. Here, we review recent advances in the DA systems neuroscience field and explore the advancing hypothesis that DA’s behavioral function is linked to disease deficits in a neural circuit-dependent manner. We survey different brain areas including the basal ganglia’s dorsomedial/dorsolateral striatum, the ventral striatum, the auditory striatum, and the hippocampus in rodent models. Each of these regions have different reported functions and, correspondingly, DA’s reflecting role in each of these regions also has support for being different. We then focus on DA dysregulation states in Parkinson’s disease, addiction, and Alzheimer’s Disease, emphasizing how these afflictions are linked to different DA pathways. We draw upon ideas such as selective vulnerability and region-dependent physiology. These bodies of work suggest that different channels of DA may be dysregulated in different sets of disease. While these are great advances, the fine and definitive segregation of such pathways in behavior and disease remains to be seen. Future studies will be required to define DA’s necessity and contribution to the functional plasticity of different striatal regions.
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Affiliation(s)
- Allen PF Chen
- Department of Neurobiology and Behavior, Renaissance School of Medicine at Stony Brook University, Stony Brook, NY 11794, USA; (A.P.C.); (L.C.); (T.A.K.)
- Medical Scientist Training Program, Renaissance School of Medicine at Stony Brook University, Stony Brook, NY 11794, USA
| | - Lu Chen
- Department of Neurobiology and Behavior, Renaissance School of Medicine at Stony Brook University, Stony Brook, NY 11794, USA; (A.P.C.); (L.C.); (T.A.K.)
| | - Thomas A. Kim
- Department of Neurobiology and Behavior, Renaissance School of Medicine at Stony Brook University, Stony Brook, NY 11794, USA; (A.P.C.); (L.C.); (T.A.K.)
- Medical Scientist Training Program, Renaissance School of Medicine at Stony Brook University, Stony Brook, NY 11794, USA
| | - Qiaojie Xiong
- Department of Neurobiology and Behavior, Renaissance School of Medicine at Stony Brook University, Stony Brook, NY 11794, USA; (A.P.C.); (L.C.); (T.A.K.)
- Correspondence:
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21
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Cassidy CM, Konova AB, Abi-Dargham A, Martinez D, Horga G. Ubiquitous Dopamine Deficit Hypotheses in Cocaine Use Disorder Lack Support: Response to Leyton. Am J Psychiatry 2021; 178:469-470. [PMID: 33979543 DOI: 10.1176/appi.ajp.2020.20111581r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Clifford M Cassidy
- University of Ottawa Institute of Mental Health Research, affiliated with The Royal, Ottawa (Cassidy); Department of Psychiatry, Columbia University College of Physicians and Surgeons, and New York State Psychiatric Institute, New York (Cassidy, Abi-Dargham, Martinez, Horga); Department of Psychiatry, Rutgers University, Piscataway, N.J. (Konova); Department of Psychiatry, Stony Brook University, Stony Brook, N.Y. (Abi-Dargham)
| | - Anna B Konova
- University of Ottawa Institute of Mental Health Research, affiliated with The Royal, Ottawa (Cassidy); Department of Psychiatry, Columbia University College of Physicians and Surgeons, and New York State Psychiatric Institute, New York (Cassidy, Abi-Dargham, Martinez, Horga); Department of Psychiatry, Rutgers University, Piscataway, N.J. (Konova); Department of Psychiatry, Stony Brook University, Stony Brook, N.Y. (Abi-Dargham)
| | - Anissa Abi-Dargham
- University of Ottawa Institute of Mental Health Research, affiliated with The Royal, Ottawa (Cassidy); Department of Psychiatry, Columbia University College of Physicians and Surgeons, and New York State Psychiatric Institute, New York (Cassidy, Abi-Dargham, Martinez, Horga); Department of Psychiatry, Rutgers University, Piscataway, N.J. (Konova); Department of Psychiatry, Stony Brook University, Stony Brook, N.Y. (Abi-Dargham)
| | - Diana Martinez
- University of Ottawa Institute of Mental Health Research, affiliated with The Royal, Ottawa (Cassidy); Department of Psychiatry, Columbia University College of Physicians and Surgeons, and New York State Psychiatric Institute, New York (Cassidy, Abi-Dargham, Martinez, Horga); Department of Psychiatry, Rutgers University, Piscataway, N.J. (Konova); Department of Psychiatry, Stony Brook University, Stony Brook, N.Y. (Abi-Dargham)
| | - Guillermo Horga
- University of Ottawa Institute of Mental Health Research, affiliated with The Royal, Ottawa (Cassidy); Department of Psychiatry, Columbia University College of Physicians and Surgeons, and New York State Psychiatric Institute, New York (Cassidy, Abi-Dargham, Martinez, Horga); Department of Psychiatry, Rutgers University, Piscataway, N.J. (Konova); Department of Psychiatry, Stony Brook University, Stony Brook, N.Y. (Abi-Dargham)
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22
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Muddapu VR, Chakravarthy VS. Influence of energy deficiency on the subcellular processes of Substantia Nigra Pars Compacta cell for understanding Parkinsonian neurodegeneration. Sci Rep 2021; 11:1754. [PMID: 33462293 PMCID: PMC7814067 DOI: 10.1038/s41598-021-81185-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Accepted: 12/23/2020] [Indexed: 01/29/2023] Open
Abstract
Parkinson's disease (PD) is the second most prominent neurodegenerative disease around the world. Although it is known that PD is caused by the loss of dopaminergic cells in substantia nigra pars compacta (SNc), the decisive cause of this inexorable cell loss is not clearly elucidated. We hypothesize that "Energy deficiency at a sub-cellular/cellular/systems level can be a common underlying cause for SNc cell loss in PD." Here, we propose a comprehensive computational model of SNc cell, which helps us to understand the pathophysiology of neurodegeneration at the subcellular level in PD. The aim of the study is to see how deficits in the supply of energy substrates (glucose and oxygen) lead to a deficit in adenosine triphosphate (ATP). The study also aims to show that deficits in ATP are the common factor underlying the molecular-level pathological changes, including alpha-synuclein aggregation, reactive oxygen species formation, calcium elevation, and dopamine dysfunction. The model suggests that hypoglycemia plays a more crucial role in leading to ATP deficits than hypoxia. We believe that the proposed model provides an integrated modeling framework to understand the neurodegenerative processes underlying PD.
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Affiliation(s)
- Vignayanandam Ravindernath Muddapu
- grid.417969.40000 0001 2315 1926Computational Neuroscience Lab, Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Sardar Patel Road, Chennai, 600036 Tamil Nadu India
| | - V. Srinivasa Chakravarthy
- grid.417969.40000 0001 2315 1926Computational Neuroscience Lab, Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Sardar Patel Road, Chennai, 600036 Tamil Nadu India
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23
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The Neuromelanin Paradox and Its Dual Role in Oxidative Stress and Neurodegeneration. Antioxidants (Basel) 2021; 10:antiox10010124. [PMID: 33467040 PMCID: PMC7829956 DOI: 10.3390/antiox10010124] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 01/12/2021] [Accepted: 01/13/2021] [Indexed: 12/12/2022] Open
Abstract
Aging is associated with an increasing dysfunction of key brain homeostasis mechanisms and represents the main risk factor across most neurodegenerative disorders. However, the degree of dysregulation and the affectation of specific pathways set apart normal aging from neurodegenerative disorders. In particular, the neuronal metabolism of catecholaminergic neurotransmitters appears to be a specifically sensitive pathway that is affected in different neurodegenerations. In humans, catecholaminergic neurons are characterized by an age-related accumulation of neuromelanin (NM), rendering the soma of the neurons black. This intracellular NM appears to serve as a very efficient quencher for toxic molecules. However, when a neuron degenerates, NM is released together with its load (many undegraded cellular components, transition metals, lipids, xenobiotics) contributing to initiate and worsen an eventual immune response, exacerbating the oxidative stress, ultimately leading to the neurodegenerative process. This review focuses on the analysis of the role of NM in normal aging and neurodegeneration related to its capabilities as an antioxidant and scavenging of harmful molecules, versus its involvement in oxidative stress and aberrant immune response, depending on NM saturation state and its extracellular release.
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Cassidy CM, Carpenter KM, Konova AB, Cheung V, Grassetti A, Zecca L, Abi-Dargham A, Martinez D, Horga G. Evidence for Dopamine Abnormalities in the Substantia Nigra in Cocaine Addiction Revealed by Neuromelanin-Sensitive MRI. Am J Psychiatry 2020; 177:1038-1047. [PMID: 32854531 PMCID: PMC9108998 DOI: 10.1176/appi.ajp.2020.20010090] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Recent evidence supports the use of neuromelanin-sensitive MRI (NM-MRI) as a novel tool to investigate dopamine function in the human brain. The authors investigated the NM-MRI signal in individuals with cocaine use disorder, compared with age- and sex-matched control subjects, based on previous imaging studies showing that this disorder is associated with blunted presynaptic striatal dopamine. METHODS NM-MRI and T1-weighted images were acquired from 20 participants with cocaine use disorder and 35 control subjects. Diagnostic group effects in NM-MRI signal were determined using a voxelwise analysis within the substantia nigra. A subset of 20 cocaine users and 17 control subjects also underwent functional MRI imaging using the monetary incentive delay task, in order to investigate whether NM-MRI signal was associated with alterations in reward processing. RESULTS Compared with control subjects, cocaine users showed significantly increased NM-MRI signal in ventrolateral regions of the substantia nigra (area under the receiver operating characteristic curve=0.83). Exploratory analyses did not find a significant correlation of NM-MRI signal to activation of the ventral striatum during anticipation of monetary reward. CONCLUSIONS Given that previous imaging studies show decreased dopamine signaling in the striatum, the finding of increased NM-MRI signal in the substantia nigra provides additional insight into the pathophysiology of cocaine use disorder. One interpretation is that cocaine use disorder is associated with a redistribution of dopamine between cytosolic and vesicular pools, leading to increased accumulation of neuromelanin. The study findings thus suggest that NM-MRI can serve as a practical imaging tool for interrogating the dopamine system in addiction.
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Affiliation(s)
- Clifford M Cassidy
- University of Ottawa Institute of Mental Health Research, affiliated with The Royal, Ottawa, ON,Department of Psychiatry, Columbia University College of Physicians and Surgeons and the New York State Psychiatric Institute, New York, NY,Corresponding author: Clifford Cassidy, 1145 Carling Ave, Ottawa ON, K1Z 7K4, Canada.
| | - Kenneth M Carpenter
- Department of Psychiatry, Columbia University College of Physicians and Surgeons and the New York State Psychiatric Institute, New York, NY
| | - Anna B Konova
- Department of Psychiatry, Rutgers University, Newark, NJ
| | - Victoria Cheung
- University of Ottawa Institute of Mental Health Research, affiliated with The Royal, Ottawa, ON
| | - Alexander Grassetti
- Department of Psychiatry, Columbia University College of Physicians and Surgeons and the New York State Psychiatric Institute, New York, NY
| | - Luigi Zecca
- Institute of Biomedical Technologies, National Research Council of Italy, Milan, Italy
| | - Anissa Abi-Dargham
- Department of Psychiatry, Columbia University College of Physicians and Surgeons and the New York State Psychiatric Institute, New York, NY,Department of Psychiatry, Stony Brook University, Stony Brook, NY
| | - Diana Martinez
- Department of Psychiatry, Columbia University College of Physicians and Surgeons and the New York State Psychiatric Institute, New York, NY
| | - Guillermo Horga
- Department of Psychiatry, Columbia University College of Physicians and Surgeons and the New York State Psychiatric Institute, New York, NY
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25
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Muddapu VR, Dharshini SAP, Chakravarthy VS, Gromiha MM. Neurodegenerative Diseases - Is Metabolic Deficiency the Root Cause? Front Neurosci 2020; 14:213. [PMID: 32296300 PMCID: PMC7137637 DOI: 10.3389/fnins.2020.00213] [Citation(s) in RCA: 120] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Accepted: 02/26/2020] [Indexed: 01/31/2023] Open
Abstract
Neurodegenerative diseases, including Alzheimer, Parkinson, Huntington, and amyotrophic lateral sclerosis, are a prominent class of neurological diseases currently without a cure. They are characterized by an inexorable loss of a specific type of neurons. The selective vulnerability of specific neuronal clusters (typically a subcortical cluster) in the early stages, followed by the spread of the disease to higher cortical areas, is a typical pattern of disease progression. Neurodegenerative diseases share a range of molecular and cellular pathologies, including protein aggregation, mitochondrial dysfunction, glutamate toxicity, calcium load, proteolytic stress, oxidative stress, neuroinflammation, and aging, which contribute to neuronal death. Efforts to treat these diseases are often limited by the fact that they tend to address any one of the above pathological changes while ignoring others. Lack of clarity regarding a possible root cause that underlies all the above pathologies poses a significant challenge. In search of an integrative theory for neurodegenerative pathology, we hypothesize that metabolic deficiency in certain vulnerable neuronal clusters is the common underlying thread that links many dimensions of the disease. The current review aims to present an outline of such an integrative theory. We present a new perspective of neurodegenerative diseases as metabolic disorders at molecular, cellular, and systems levels. This helps to understand a common underlying mechanism of the many facets of the disease and may lead to more promising disease-modifying therapeutic interventions. Here, we briefly discuss the selective metabolic vulnerability of specific neuronal clusters and also the involvement of glia and vascular dysfunctions. Any failure in satisfaction of the metabolic demand by the neurons triggers a chain of events that precipitate various manifestations of neurodegenerative pathology.
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Affiliation(s)
- Vignayanandam Ravindernath Muddapu
- Laboratory for Computational Neuroscience, Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai, India
| | - S. Akila Parvathy Dharshini
- Protein Bioinformatics Lab, Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai, India
| | - V. Srinivasa Chakravarthy
- Laboratory for Computational Neuroscience, Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai, India
| | - M. Michael Gromiha
- Protein Bioinformatics Lab, Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai, India
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26
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Parkinson's disease treatment: past, present, and future. J Neural Transm (Vienna) 2020; 127:785-791. [PMID: 32172471 DOI: 10.1007/s00702-020-02167-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Accepted: 03/03/2020] [Indexed: 12/15/2022]
Abstract
The substantial contributions of Dr. Gerald Stern to past and current treatments for Parkinson's disease patients are reviewed, which form the foundation for an evaluation of future options to control symptoms and halt progression of the disease. These opportunities will depend on a greater understanding of the relative contributions of the environment, genetic and epigenetic influences to disease onset, and promise to emerge as strategies for improving mitochondrial function, halting accumulation of synuclein and neuromelanin, in addition to refinement of stem cell and gene therapies. Such advances will be achieved through deployment of improved models for the disease.
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27
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Kaalund SS, Passamonti L, Allinson KSJ, Murley AG, Robbins TW, Spillantini MG, Rowe JB. Locus coeruleus pathology in progressive supranuclear palsy, and its relation to disease severity. Acta Neuropathol Commun 2020; 8:11. [PMID: 32019605 PMCID: PMC7001334 DOI: 10.1186/s40478-020-0886-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 01/26/2020] [Indexed: 01/28/2023] Open
Abstract
The locus coeruleus is the major source of noradrenaline to the brain and contributes to a wide range of physiological and cognitive functions including arousal, attention, autonomic control, and adaptive behaviour. Neurodegeneration and pathological aggregation of tau protein in the locus coeruleus are early features of progressive supranuclear palsy (PSP). This pathology is proposed to contribute to the clinical expression of disease, including the PSP Richardson's syndrome. We test the hypothesis that tau pathology and neuronal loss are associated with clinical heterogeneity and severity in PSP.We used immunohistochemistry in post mortem tissues from 31 patients with a clinical diagnosis of PSP (22 with Richardson's syndrome) and 6 control cases. We quantified the presence of hyperphosphorylated tau, the number of pigmented cells indicative of noradrenergic neurons, and the percentage of pigmented neurons with tau-positive inclusions. Ante mortem assessment of clinical severity using the PSP rating scale was available within 1.8 (±0.9) years for 23 patients.We found an average 49% reduction of pigmented neurons in PSP patients relative to controls. The loss of pigmented neurons correlated with disease severity, even after adjusting for disease duration and the interval between clinical assessment and death. The degree of neuronal loss was negatively associated with tau-positive inclusions, with an average of 44% of pigmented neurons displaying tau-inclusions.Degeneration and tau pathology in the locus coeruleus are related to clinical heterogeneity of PSP. The noradrenergic deficit in the locus coeruleus is a candidate target for pharmacological treatment. Recent developments in ultra-high field magnetic resonance imaging to quantify in vivo structural integrity of the locus coeruleus may provide biomarkers for noradrenergic experimental medicines studies in PSP.
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Affiliation(s)
- Sanne Simone Kaalund
- Cambridge University Centre for Parkinson-plus and Department of Clinical Neurosciences, University of Cambridge, Robinson Way, Cambridge, CB2 0SZ UK
- Danish Research Centre for Magnetic Resonance (DRCMR), Centre for Functional and Diagnostic Imaging Research, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark
| | - Luca Passamonti
- Cambridge University Centre for Parkinson-plus and Department of Clinical Neurosciences, University of Cambridge, Robinson Way, Cambridge, CB2 0SZ UK
- Consiglio Nazionale delle Ricerche (CNR), Istituto di Bioimmagini e Fisiologia Molecolare (IBFM), Milan, Italy
- Cambridge University Hospitals NHS Foundation Trust and the Cambridge Brain Bank, Cambridge, UK
| | - Kieren S. J. Allinson
- Cambridge University Hospitals NHS Foundation Trust and the Cambridge Brain Bank, Cambridge, UK
| | - Alexander G. Murley
- Cambridge University Centre for Parkinson-plus and Department of Clinical Neurosciences, University of Cambridge, Robinson Way, Cambridge, CB2 0SZ UK
| | - Trevor W. Robbins
- Department of Psychology and Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, UK
| | - Maria Grazia Spillantini
- Cambridge University Centre for Parkinson-plus and Department of Clinical Neurosciences, University of Cambridge, Robinson Way, Cambridge, CB2 0SZ UK
| | - James B. Rowe
- Cambridge University Centre for Parkinson-plus and Department of Clinical Neurosciences, University of Cambridge, Robinson Way, Cambridge, CB2 0SZ UK
- Danish Research Centre for Magnetic Resonance (DRCMR), Centre for Functional and Diagnostic Imaging Research, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark
- Cambridge University Hospitals NHS Foundation Trust and the Cambridge Brain Bank, Cambridge, UK
- Medical Research Council Cognition and Brain Sciences Unit, University of Cambridge, Cambridge, UK
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28
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Zhang C, Huo S, Fan Y, Gao Y, Yang Y, Sun D. Autophagy May Be Involved in Fluoride-Induced Learning Impairment in Rats. Biol Trace Elem Res 2020; 193:502-507. [PMID: 31111310 DOI: 10.1007/s12011-019-01735-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Accepted: 01/22/2019] [Indexed: 12/30/2022]
Abstract
Fluoride can induce neurotoxicity, but the mechanism is not clear. In this study, we explored the role of autophagy in F--induced neurotoxicity of Wistar rats. Eighty Wistar rats were randomly divided into four groups: the control group (distilled water containing less than 0.1 mg/L F-) and three NaF-treated groups (F- was respectively administered at 25, 50, and 100 mg/L orally via drinking water). The water maze experiment showed that NaF exposure impaired the learning capabilities of the rats. When compared with the control group, the mean escape latency of the rats in the 100 mg/L F- group was much longer (P < 0.05). Immunohistochemical analysis showed that NaF exposure induced autophagy, as shown by the significant increase of Beclin-1 expression in the hippocampal CA1 region and DG region. Transmission electron microscopy was used to observe the ultrastructural changes of hippocampal neurons. With the increase of F- concentration, the ultrastructural abnormalities of hippocampal neurons increased. These results indicate that fluoride can impair the learning ability of rats, which may be related to the induction of autophagy in rat hippocampal neurons.
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Affiliation(s)
- Chengzhi Zhang
- Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Key Lab of Etiology and Epidemiology, Education Bureau of Heilongjiang Province & Ministry of Health, Harbin, 150081, China
| | - Simeng Huo
- Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Key Lab of Etiology and Epidemiology, Education Bureau of Heilongjiang Province & Ministry of Health, Harbin, 150081, China
| | - Yumei Fan
- Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Key Lab of Etiology and Epidemiology, Education Bureau of Heilongjiang Province & Ministry of Health, Harbin, 150081, China
| | - Yanhui Gao
- Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Key Lab of Etiology and Epidemiology, Education Bureau of Heilongjiang Province & Ministry of Health, Harbin, 150081, China
| | - Yanmei Yang
- Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Key Lab of Etiology and Epidemiology, Education Bureau of Heilongjiang Province & Ministry of Health, Harbin, 150081, China
| | - Dianjun Sun
- Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Key Lab of Etiology and Epidemiology, Education Bureau of Heilongjiang Province & Ministry of Health, Harbin, 150081, China.
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29
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Wengler K, He X, Abi-Dargham A, Horga G. Reproducibility assessment of neuromelanin-sensitive magnetic resonance imaging protocols for region-of-interest and voxelwise analyses. Neuroimage 2019; 208:116457. [PMID: 31841683 PMCID: PMC7118586 DOI: 10.1016/j.neuroimage.2019.116457] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 12/05/2019] [Accepted: 12/09/2019] [Indexed: 01/02/2023] Open
Abstract
Neuromelanin-sensitive MRI (NM-MRI) provides a noninvasive measure of the content of neuromelanin (NM), a product of dopamine metabolism that accumulates with age in dopamine neurons of the substantia nigra (SN). NM-MRI has been validated as a measure of both dopamine neuron loss, with applications in neurodegenerative disease, and dopamine function, with applications in psychiatric disease. Furthermore, a voxelwise-analysis approach has been validated to resolve substructures, such as the ventral tegmental area (VTA), within midbrain dopaminergic nuclei thought to have distinct anatomical targets and functional roles. NM-MRI is thus a promising tool that could have diverse research and clinical applications to noninvasively interrogate in vivo the dopamine system in neuropsychiatric illness. Although a test-retest reliability study by Langley et al. using the standard NM-MRI protocol recently reported high reliability, a systematic and comprehensive investigation of the performance of the method for various acquisition parameters and preprocessing methods has not been conducted. In particular, most previous studies used relatively thick MRI slices (~3 mm), compared to the typical in-plane resolution (~0.5 mm) and to the height of the SN (~15 mm), to overcome technical limitations such as specific absorption rate and signal-to-noise ratio, at the cost of partial-volume effects. Here, we evaluated the effect of various acquisition and preprocessing parameters on the strength and test-retest reliability of the NM-MRI signal to determine optimized protocols for both region-of-interest (including whole SN-VTA complex and atlas-defined dopaminergic nuclei) and voxelwise measures. Namely, we determined a combination of parameters that optimizes the strength and reliability of the NM-MRI signal, including acquisition time, slice-thickness, spatial-normalization software, and degree of spatial smoothing. Using a newly developed, detailed acquisition protocol, across two scans separated by 13 days on average, we obtained intra-class correlation values indicating excellent reliability and high contrast, which could be achieved with a different set of parameters depending on the measures of interest and experimental constraints such as acquisition time. Based on this, we provide detailed guidelines covering acquisition through analysis and recommendations for performing NM-MRI experiments with high quality and reproducibility. This work provides a foundation for the optimization and standardization of NM-MRI, a promising MRI approach with growing applications throughout clinical and basic neuroscience.
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Affiliation(s)
- Kenneth Wengler
- Department of Psychiatry, Columbia University, and New York State Psychiatric Institute, New York, NY, USA; Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY, USA.
| | - Xiang He
- Department of Radiology, Stony Brook University, Stony Brook, NY, USA
| | - Anissa Abi-Dargham
- Department of Radiology, Stony Brook University, Stony Brook, NY, USA; Department of Psychiatry, Stony Brook University, Stony Brook, NY, USA
| | - Guillermo Horga
- Department of Psychiatry, Columbia University, and New York State Psychiatric Institute, New York, NY, USA
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30
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Sergi D, Renaud J, Simola N, Martinoli MG. Diabetes, a Contemporary Risk for Parkinson's Disease: Epidemiological and Cellular Evidences. Front Aging Neurosci 2019; 11:302. [PMID: 31787891 PMCID: PMC6856011 DOI: 10.3389/fnagi.2019.00302] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Accepted: 10/22/2019] [Indexed: 12/14/2022] Open
Abstract
Diabetes mellitus (DM), a group of diseases characterized by defective glucose metabolism, is the most widespread metabolic disorder affecting over 400 million adults worldwide. This pathological condition has been implicated in the pathogenesis of a number of central encephalopathies and peripheral neuropathies. In further support of this notion, recent epidemiological evidence suggests a link between DM and Parkinson’s disease (PD), with hyperglycemia emerging as one of the culprits in neurodegeneration involving the nigrostriatal pathway, the neuroanatomical substrate of the motor symptoms affecting parkinsonian patients. Indeed, dopaminergic neurons located in the mesencephalic substantia nigra appear to be particularly vulnerable to oxidative stress and degeneration, likely because of their intrinsic susceptibility to mitochondrial dysfunction, which may represent a direct consequence of hyperglycemia and hyperglycemia-induced oxidative stress. Other pathological pathways induced by increased intracellular glucose levels, including the polyol and the hexosamine pathway as well as the formation of advanced glycation end-products, may all play a pivotal role in mediating the detrimental effects of hyperglycemia on nigral dopaminergic neurons. In this review article, we will examine the epidemiological as well as the molecular and cellular clues supporting the potential susceptibility of nigrostriatal dopaminergic neurons to hyperglycemia.
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Affiliation(s)
- Domenico Sergi
- Nutrition and Health Substantiation Group, Nutrition and Health Program, Health and Biosecurity, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Adelaide, SA, Australia.,Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
| | - Justine Renaud
- Cellular Neurobiology, Department of Medical Biology, Université du Québec, Trois-Rivières, QC, Canada
| | - Nicola Simola
- Department of Biomedical Sciences, University of Cagliari, Cagliari, Italy.,National Institute for Neuroscience (INN), University of Cagliari, Cagliari, Italy
| | - Maria-Grazia Martinoli
- Cellular Neurobiology, Department of Medical Biology, Université du Québec, Trois-Rivières, QC, Canada.,Department of Psychiatry and Neuroscience, Université Laval and CHU Research Center, Québec, QC, Canada
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31
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Vila M. Neuromelanin, aging, and neuronal vulnerability in Parkinson's disease. Mov Disord 2019; 34:1440-1451. [PMID: 31251435 PMCID: PMC7079126 DOI: 10.1002/mds.27776] [Citation(s) in RCA: 68] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 05/29/2019] [Accepted: 05/30/2019] [Indexed: 12/22/2022] Open
Abstract
Neuromelanin, a dark brown intracellular pigment, has long been associated with Parkinson's disease (PD). In PD, neuromelanin-containing neurons preferentially degenerate, tell-tale neuropathological inclusions form in close association with this pigment, and neuroinflammation is restricted to neuromelanin-containing areas. In humans, neuromelanin accumulates with age, which in turn is the main risk factor for PD. The potential contribution of neuromelanin to PD pathogenesis remains unknown because, in contrast to humans, common laboratory animals lack neuromelanin. The recent introduction of a rodent model exhibiting an age-dependent production of human-like neuromelanin has allowed, for the first time, for the consequences of progressive neuromelanin accumulation-up to levels reached in elderly human brains-to be assessed in vivo. In these animals, intracellular neuromelanin accumulation above a specific threshold compromises neuronal function and triggers a PD-like pathology. As neuromelanin levels reach this threshold in PD patients and presymptomatic PD patients, the modulation of neuromelanin accumulation could provide a therapeutic benefit for PD patients and delay brain aging. © 2019 The Author. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Miquel Vila
- Neurodegenerative Diseases Research GroupVall d'Hebron Research Institute–Center for Networked Biomedical Research on Neurodegenerative DiseasesBarcelonaSpain
- Department of Biochemistry and Molecular BiologyAutonomous University of BarcelonaBarcelonaSpain
- Catalan Institution for Research and Advanced StudiesBarcelonaSpain
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32
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Development of a Competition-Binding Assay to Determine Binding Affinity of Molecules to Neuromelanin via Fluorescence Spectroscopy. Biomolecules 2019; 9:biom9050175. [PMID: 31072013 PMCID: PMC6572089 DOI: 10.3390/biom9050175] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Revised: 05/02/2019] [Accepted: 05/03/2019] [Indexed: 11/16/2022] Open
Abstract
Neuromelanin, the polymeric form of dopamine which accumulates in aging neuronal tissue, is increasingly recognized as a functional and critical component of a healthy and active adult human brain. Notorious in plant and insect literature for their ability to bind and retain amines for long periods of time, catecholamine polymers known colloquially as 'melanins' are nevertheless curiously absent from most textbooks regarding biochemistry, neuroscience, and evolution. Recent research has brought attention to the brain pigment due to its possible role in neurodegeneration. This linkage is best illustrated by Parkinson's disease, which is characterized by the loss of pigmented dopaminergic neurons and the 'white brain' pathological state. As such, the ability to determine the binding affinity of neurotoxic agents, as well as any potential specific endogenous ligands to neuromelanin are of interest and potential value. Neuromelanin has been shown to have saturable binding interactions with nicotine as monitored by a fluorimeter. This interaction provides a signal to allow for a competition-binding assay with target molecules which do not themselves produce signal. The current report establishes the viability of this competition assay toward three compounds with central relevance to Parkinson's disease. The Kd of binding toward neuromelanin by methyl-phenyl-pyridinium ion (MPP+), dopamine, and 6-hydroxydopamine were found to be 1 mM, 0.05 mM, and 0.1 mM, respectively in the current study. In addition, we demonstrate that 6-hydroxydopamine polymerizes to form neuromelanin granules in cultured dopaminergic neurons that treated with 2,4,5-trihydroxy-l-phenylalanine. Immunohistochemical analysis using fluor-tagged anti-dopamine antibodies suggests that the incorporation of 6-hydroxydopamine (following internalization and decarboxylation analogous to levodopa and dopamine) alters the localized distribution of bound dopamine in these cells.
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33
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Segura-Aguilar J. The importance of choosing a preclinical model that reflects what happens in Parkinson's disease. Neurochem Int 2019; 126:203-209. [PMID: 30922924 DOI: 10.1016/j.neuint.2019.03.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 03/19/2019] [Accepted: 03/21/2019] [Indexed: 02/06/2023]
Abstract
One of the major problems in the translation of successful preclinical results to clinical studies and new therapies in Parkinson's disease is the use of preclinical models based on exogenous neurotoxins that do not replicate what happens in the disease. The loss of dopaminergic neurons containing neuromelanin in Parkinson´s disease takes years, contrasting the very rapid degeneration induced by exogenous neurotoxins. We discuss the role of endogenous neurotoxins generated during dopamine oxidation and its possible use as new preclinical models for Parkinson´s disease.
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Affiliation(s)
- Juan Segura-Aguilar
- Molecular and Clinical Pharmacology, ICBM, Faculty of Medicine, University of Chile, Independencia 1027, 8350453, Independencia, Santiago, Chile.
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34
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Monzani E, Nicolis S, Dell'Acqua S, Capucciati A, Bacchella C, Zucca FA, Mosharov EV, Sulzer D, Zecca L, Casella L. Dopamin, oxidativer Stress und Protein‐Chinonmodifikationen bei Parkinson und anderen neurodegenerativen Erkrankungen. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201811122] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Enrico Monzani
- Department of ChemistryUniversity of Pavia 27100 Pavia Italien
| | | | | | | | | | - Fabio A. Zucca
- Institute of Biomedical TechnologiesNational Research Council of Italy Segrate (Mailand) Italien
| | - Eugene V. Mosharov
- Department of PsychiatryColumbia University Medical CenterNew York State Psychiatric Institute New York NY USA
- Departments Neurology, PharmacologyColumbia University Medical Center New York NY USA
| | - David Sulzer
- Department of PsychiatryColumbia University Medical CenterNew York State Psychiatric Institute New York NY USA
- Departments Neurology, PharmacologyColumbia University Medical Center New York NY USA
| | - Luigi Zecca
- Institute of Biomedical TechnologiesNational Research Council of Italy Segrate (Mailand) Italien
- Department of PsychiatryColumbia University Medical CenterNew York State Psychiatric Institute New York NY USA
| | - Luigi Casella
- Department of ChemistryUniversity of Pavia 27100 Pavia Italien
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35
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Monzani E, Nicolis S, Dell'Acqua S, Capucciati A, Bacchella C, Zucca FA, Mosharov EV, Sulzer D, Zecca L, Casella L. Dopamine, Oxidative Stress and Protein-Quinone Modifications in Parkinson's and Other Neurodegenerative Diseases. Angew Chem Int Ed Engl 2019; 58:6512-6527. [PMID: 30536578 DOI: 10.1002/anie.201811122] [Citation(s) in RCA: 144] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Revised: 12/10/2018] [Indexed: 12/19/2022]
Abstract
Dopamine (DA) is the most important catecholamine in the brain, as it is the most abundant and the precursor of other neurotransmitters. Degeneration of nigrostriatal neurons of substantia nigra pars compacta in Parkinson's disease represents the best-studied link between DA neurotransmission and neuropathology. Catecholamines are reactive molecules that are handled through complex control and transport systems. Under normal conditions, small amounts of cytosolic DA are converted to neuromelanin in a stepwise process involving melanization of peptides and proteins. However, excessive cytosolic or extraneuronal DA can give rise to nonselective protein modifications. These reactions involve DA oxidation to quinone species and depend on the presence of redox-active transition metal ions such as iron and copper. Other oxidized DA metabolites likely participate in post-translational protein modification. Thus, protein-quinone modification is a heterogeneous process involving multiple DA-derived residues that produce structural and conformational changes of proteins and can lead to aggregation and inactivation of the modified proteins.
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Affiliation(s)
- Enrico Monzani
- Department of Chemistry, University of Pavia, 27100, Pavia, Italy
| | - Stefania Nicolis
- Department of Chemistry, University of Pavia, 27100, Pavia, Italy
| | | | | | - Chiara Bacchella
- Department of Chemistry, University of Pavia, 27100, Pavia, Italy
| | - Fabio A Zucca
- Institute of Biomedical Technologies, National Research Council of Italy, Segrate (Milano), Italy
| | - Eugene V Mosharov
- Department of Psychiatry, Columbia University Medical Center, New York State Psychiatric Institute, New York, NY, USA
| | - David Sulzer
- Department of Psychiatry, Columbia University Medical Center, New York State Psychiatric Institute, New York, NY, USA.,Departments of Neurology and Pharmacology, Columbia University Medical Center, New York, NY, USA
| | - Luigi Zecca
- Institute of Biomedical Technologies, National Research Council of Italy, Segrate (Milano), Italy.,Department of Psychiatry, Columbia University Medical Center, New York State Psychiatric Institute, New York, NY, USA
| | - Luigi Casella
- Department of Chemistry, University of Pavia, 27100, Pavia, Italy
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36
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Muddapu VR, Mandali A, Chakravarthy VS, Ramaswamy S. A Computational Model of Loss of Dopaminergic Cells in Parkinson's Disease Due to Glutamate-Induced Excitotoxicity. Front Neural Circuits 2019; 13:11. [PMID: 30858799 PMCID: PMC6397878 DOI: 10.3389/fncir.2019.00011] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Accepted: 02/05/2019] [Indexed: 01/04/2023] Open
Abstract
Parkinson's disease (PD) is a neurodegenerative disease associated with progressive and inexorable loss of dopaminergic cells in Substantia Nigra pars compacta (SNc). Although many mechanisms have been suggested, a decisive root cause of this cell loss is unknown. A couple of the proposed mechanisms, however, show potential for the development of a novel line of PD therapeutics. One of these mechanisms is the peculiar metabolic vulnerability of SNc cells compared to other dopaminergic clusters; the other is the SubThalamic Nucleus (STN)-induced excitotoxicity in SNc. To investigate the latter hypothesis computationally, we developed a spiking neuron network-model of SNc-STN-GPe system. In the model, prolonged stimulation of SNc cells by an overactive STN leads to an increase in ‘stress' variable; when the stress in a SNc neuron exceeds a stress threshold, the neuron dies. The model shows that the interaction between SNc and STN involves a positive-feedback due to which, an initial loss of SNc cells that crosses a threshold causes a runaway-effect, leading to an inexorable loss of SNc cells, strongly resembling the process of neurodegeneration. The model further suggests a link between the two aforementioned mechanisms of SNc cell loss. Our simulation results show that the excitotoxic cause of SNc cell loss might initiate by weak-excitotoxicity mediated by energy deficit, followed by strong-excitotoxicity, mediated by a disinhibited STN. A variety of conventional therapies were simulated to test their efficacy in slowing down SNc cell loss. Among them, glutamate inhibition, dopamine restoration, subthalamotomy and deep brain stimulation showed superior neuroprotective-effects in the proposed model.
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Affiliation(s)
| | - Alekhya Mandali
- Department of Psychiatry, Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, United Kingdom
| | - V Srinivasa Chakravarthy
- Computational Neuroscience Lab, Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, IIT-Madras, Chennai, India
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37
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Uhl GR. Dopamine compartmentalization, selective dopaminergic vulnerabilities in Parkinson's disease and therapeutic opportunities. Ann Clin Transl Neurol 2019; 6:406-415. [PMID: 30847375 PMCID: PMC6389739 DOI: 10.1002/acn3.707] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 09/29/2018] [Accepted: 11/05/2018] [Indexed: 12/13/2022] Open
Abstract
Progressive depletion of selected dopamine neurons is central to much Parkinson's disease (PD) disability. Although symptomatic treatments can ameliorate the disabilities that this neuronal depletion causes, no current strategy is documented to slow these losses. There is substantial evidence that dopamine in intracytoplasmic/extravesicular neuronal compartments can be toxic. Here, I review evidence that supports roles for dopamine compartmentalization, mediated largely by serial actions of plasma membrane SLC6A3/DAT and vesicular SLC18A2/VMAT2 transporters, in the selective patterns of dopamine neuronal loss found in PD brains. This compartmentalization hypothesis for the dopamine cell type specificity of PD lesions nominates available drugs for amelioration of damage arising from miscompartmentalized dopamine and raises cautions in using other drugs.
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Affiliation(s)
- George R. Uhl
- Neurology and Research ServicesNew Mexico VA HealthCare SystemAlbuquerqueNew Mexico87108
- Biomedical Research Institute of New MexicoAlbuquerqueNew Mexico87108
- Departments of Neurology, Neuroscience and Molecular Genetics and MicrobiologyUniversity of New MexicoAlbuquerqueNew Mexico87108
- Departments of Neurology, Neuroscience and Mental HealthJohns Hopkins Medical InstitutionsBaltimoreMaryland21287
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38
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Dopamine: Functions, Signaling, and Association with Neurological Diseases. Cell Mol Neurobiol 2018; 39:31-59. [PMID: 30446950 DOI: 10.1007/s10571-018-0632-3] [Citation(s) in RCA: 459] [Impact Index Per Article: 76.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 11/02/2018] [Indexed: 02/07/2023]
Abstract
The dopaminergic system plays important roles in neuromodulation, such as motor control, motivation, reward, cognitive function, maternal, and reproductive behaviors. Dopamine is a neurotransmitter, synthesized in both central nervous system and the periphery, that exerts its actions upon binding to G protein-coupled receptors. Dopamine receptors are widely expressed in the body and function in both the peripheral and the central nervous systems. Dopaminergic signaling pathways are crucial to the maintenance of physiological processes and an unbalanced activity may lead to dysfunctions that are related to neurodegenerative diseases. Unveiling the neurobiology and the molecular mechanisms that underlie these illnesses may contribute to the development of new therapies that could promote a better quality of life for patients worldwide. In this review, we summarize the aspects of dopamine as a catecholaminergic neurotransmitter and discuss dopamine signaling pathways elicited through dopamine receptor activation in normal brain function. Furthermore, we describe the potential involvement of these signaling pathways in evoking the onset and progression of some diseases in the nervous system, such as Parkinson's, Schizophrenia, Huntington's, Attention Deficit and Hyperactivity Disorder, and Addiction. A brief description of new dopaminergic drugs recently approved and under development treatments for these ailments is also provided.
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Zucca FA, Vanna R, Cupaioli FA, Bellei C, De Palma A, Di Silvestre D, Mauri P, Grassi S, Prinetti A, Casella L, Sulzer D, Zecca L. Neuromelanin organelles are specialized autolysosomes that accumulate undegraded proteins and lipids in aging human brain and are likely involved in Parkinson's disease. NPJ Parkinsons Dis 2018; 4:17. [PMID: 29900402 PMCID: PMC5988730 DOI: 10.1038/s41531-018-0050-8] [Citation(s) in RCA: 88] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Revised: 04/10/2018] [Accepted: 04/17/2018] [Indexed: 01/08/2023] Open
Abstract
During aging, neuronal organelles filled with neuromelanin (a dark-brown pigment) and lipid bodies accumulate in the brain, particularly in the substantia nigra, a region targeted in Parkinson's disease. We have investigated protein and lipid systems involved in the formation of these organelles and in the synthesis of the neuromelanin of human substantia nigra. Membrane and matrix proteins characteristic of lysosomes were found in neuromelanin-containing organelles at a lower number than in typical lysosomes, indicating a reduced enzymatic activity and likely impaired capacity for lysosomal and autophagosomal fusion. The presence of proteins involved in lipid transport may explain the accumulation of lipid bodies in the organelle and the lipid component in neuromelanin structure. The major lipids observed in lipid bodies of the organelle are dolichols with lower amounts of other lipids. Proteins of aggregation and degradation pathways were present, suggesting a role for accumulation by this organelle when the ubiquitin-proteasome system is inadequate. The presence of proteins associated with aging and storage diseases may reflect impaired autophagic degradation or impaired function of lysosomal enzymes. The identification of typical autophagy proteins and double membranes demonstrates the organelle's autophagic nature and indicates that it has engulfed neuromelanin precursors from the cytosol. Based on these data, it appears that the neuromelanin-containing organelle has a very slow turnover during the life of a neuron and represents an intracellular compartment of final destination for numerous molecules not degraded by other systems.
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Affiliation(s)
- Fabio A. Zucca
- Institute of Biomedical Technologies, National Research Council of Italy, Segrate, Milan, Italy
| | - Renzo Vanna
- Institute of Biomedical Technologies, National Research Council of Italy, Segrate, Milan, Italy
- IRCCS Don Carlo Gnocchi ONLUS Foundation, Milan, Italy
| | - Francesca A. Cupaioli
- Institute of Biomedical Technologies, National Research Council of Italy, Segrate, Milan, Italy
| | - Chiara Bellei
- Institute of Biomedical Technologies, National Research Council of Italy, Segrate, Milan, Italy
| | - Antonella De Palma
- Institute of Biomedical Technologies, National Research Council of Italy, Segrate, Milan, Italy
| | - Dario Di Silvestre
- Institute of Biomedical Technologies, National Research Council of Italy, Segrate, Milan, Italy
| | - Pierluigi Mauri
- Institute of Biomedical Technologies, National Research Council of Italy, Segrate, Milan, Italy
| | - Sara Grassi
- Department of Medical Biotechnology and Translational Medicine, University of Milan, Segrate, Milan, Italy
| | - Alessandro Prinetti
- Department of Medical Biotechnology and Translational Medicine, University of Milan, Segrate, Milan, Italy
| | - Luigi Casella
- Department of Chemistry, University of Pavia, Pavia, Italy
| | - David Sulzer
- Department of Psychiatry, Columbia University Medical Center, New York State Psychiatric Institute, New York, NY USA
- Department of Neurology, Columbia University Medical Center, New York, NY USA
- Department of Pharmacology, Columbia University Medical Center, New York, NY USA
| | - Luigi Zecca
- Institute of Biomedical Technologies, National Research Council of Italy, Segrate, Milan, Italy
- Department of Psychiatry, Columbia University Medical Center, New York State Psychiatric Institute, New York, NY USA
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Barek H, Veraksa A, Sugumaran M. Drosophila melanogaster has the enzymatic machinery to make the melanic component of neuromelanin. Pigment Cell Melanoma Res 2018; 31:683-692. [PMID: 29741814 DOI: 10.1111/pcmr.12709] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Revised: 03/28/2018] [Accepted: 04/11/2018] [Indexed: 11/28/2022]
Abstract
In Drosophila, the same set of genes that are used for cuticle pigmentation and sclerotization are present in the nervous system and are responsible for neurotransmitter recycling. In this study, we carried out biochemical analysis to determine whether insects have the enzymatic machinery to make melanic component of neuromelanin. We focused our attention on two key enzymes of melanogenesis, namely phenoloxidase and dopachrome decarboxylase/tautomerase. Activity staining of the proteins isolated from the Drosophila larval brain tissue, separated by native polyacrylamide gel electrophoresis, indicated the presence of these two enzymes. Mass spectral sequence analysis of the band also supported this finding. To best of our knowledge, this is the first report on the presence of the enzymatic machinery to make melanin part of neuromelanin in any insect brain.
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Affiliation(s)
- Hanine Barek
- Department of Biology, University of Massachusetts Boston, Boston, Massachusetts
| | - Alexey Veraksa
- Department of Biology, University of Massachusetts Boston, Boston, Massachusetts
| | - Manickam Sugumaran
- Department of Biology, University of Massachusetts Boston, Boston, Massachusetts
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Sulzer D, Cassidy C, Horga G, Kang UJ, Fahn S, Casella L, Pezzoli G, Langley J, Hu XP, Zucca FA, Isaias IU, Zecca L. Neuromelanin detection by magnetic resonance imaging (MRI) and its promise as a biomarker for Parkinson's disease. NPJ PARKINSONS DISEASE 2018; 4:11. [PMID: 29644335 PMCID: PMC5893576 DOI: 10.1038/s41531-018-0047-3] [Citation(s) in RCA: 146] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 03/05/2018] [Accepted: 03/08/2018] [Indexed: 11/10/2022]
Abstract
The diagnosis of Parkinson’s disease (PD) occurs after pathogenesis is advanced and many substantia nigra (SN) dopamine neurons have already died. Now that therapies to block this neuronal loss are under development, it is imperative that the disease be diagnosed at earlier stages and that the response to therapies is monitored. Recent studies suggest this can be accomplished by magnetic resonance imaging (MRI) detection of neuromelanin (NM), the characteristic pigment of SN dopaminergic, and locus coeruleus (LC) noradrenergic neurons. NM is an autophagic product synthesized via oxidation of catecholamines and subsequent reactions, and in the SN and LC it increases linearly during normal aging. In PD, however, the pigment is lost when SN and LC neurons die. As shown nearly 25 years ago by Zecca and colleagues, NM’s avid binding of iron provides a paramagnetic source to enable electron and nuclear magnetic resonance detection, and thus a means for safe and noninvasive measure in living human brain. Recent technical improvements now provide a means for MRI to differentiate between PD patients and age-matched healthy controls, and should be able to identify changes in SN NM with age in individuals. We discuss how MRI detects NM and how this approach might be improved. We suggest that MRI of NM can be used to confirm PD diagnosis and monitor disease progression. We recommend that for subjects at risk for PD, and perhaps generally for older people, that MRI sequences performed at regular intervals can provide a pre-clinical means to detect presymptomatic PD.
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Affiliation(s)
- David Sulzer
- 1Department of Psychiatry, Columbia University Medical Center , New York State Psychiatric Institute, New York, NY USA.,2Department of Neurology, Columbia University Medical Center, New York, NY USA.,3Department of Pharmacology, Columbia University Medical Center, New York, NY USA
| | - Clifford Cassidy
- 4The Royal's Institute of Mental Health Research, Affiliated with the University of Ottawa, Ottawa, ON Canada
| | - Guillermo Horga
- 1Department of Psychiatry, Columbia University Medical Center , New York State Psychiatric Institute, New York, NY USA
| | - Un Jung Kang
- 2Department of Neurology, Columbia University Medical Center, New York, NY USA
| | - Stanley Fahn
- 2Department of Neurology, Columbia University Medical Center, New York, NY USA
| | - Luigi Casella
- 5Department of Chemistry, University of Pavia, Pavia, Italy
| | - Gianni Pezzoli
- Parkinson Institute, ASST "Gaetano Pini-CTO", Milan, Italy
| | - Jason Langley
- 7Center for Advanced NeuroImaging, University of California Riverside, Riverside, CA USA
| | - Xiaoping P Hu
- 8Department of Bioengineering, University of California Riverside, Riverside, CA USA
| | - Fabio A Zucca
- 9Institute of Biomedical Technologies, National Research Council of Italy, Milan, Italy
| | - Ioannis U Isaias
- Department of Neurology, University Hospital and Julius-Maximillian-University, Wuerzburg, Germany
| | - Luigi Zecca
- 9Institute of Biomedical Technologies, National Research Council of Italy, Milan, Italy
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Maxwell N, Castro RW, Sutherland NM, Vaughan KL, Szarowicz MD, de Cabo R, Mattison JA, Valdez G. α-Motor neurons are spared from aging while their synaptic inputs degenerate in monkeys and mice. Aging Cell 2018; 17. [PMID: 29397579 PMCID: PMC5847869 DOI: 10.1111/acel.12726] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/11/2017] [Indexed: 12/11/2022] Open
Abstract
Motor function deteriorates with advancing age, increasing the risk of adverse health outcomes. While it is well established that skeletal muscles and neuromuscular junctions (NMJs) degenerate with increasing age, the effect of aging on α‐motor neurons and their innervating synaptic inputs remains largely unknown. In this study, we examined the soma of α‐motor neurons and innervating synaptic inputs in the spinal cord of aged rhesus monkeys and mice, two species with vastly different lifespans. We found that, in both species, α‐motor neurons retain their soma size despite an accumulation of large amounts of cellular waste or lipofuscin. Interestingly, the lipofuscin profile varied considerably, indicating that α‐motor neurons age at different rates. Although the rate of aging varies, α‐motor neurons do not atrophy in old age. In fact, there is no difference in the number of motor axons populating ventral roots in old mice compared to adult mice. Moreover, the transcripts and proteins associated with α‐motor neurons do not decrease in the spinal cord of old mice. However, in aged rhesus monkeys and mice, there were fewer cholinergic and glutamatergic synaptic inputs directly abutting α‐motor neurons, evidence that aging causes α‐motor neurons to shed synaptic inputs. Thus, the loss of synaptic inputs may contribute to age‐related dysfunction of α‐motor neurons. These findings broaden our understanding of the degeneration of the somatic motor system that precipitates motor dysfunction with advancing age.
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Affiliation(s)
- Nicholas Maxwell
- Virginia Tech Carilion Research Institute; Virginia Tech; Roanoke VA USA
| | - Ryan W. Castro
- Virginia Tech Carilion Research Institute; Virginia Tech; Roanoke VA USA
- Graduate Program in Translational Biology, Medicine, and Health; Virginia Tech; Blacksburg VA USA
| | | | - Kelli L. Vaughan
- Translational Gerontology Branch; National Institute on Aging; NIH; Baltimore MD USA
- SoBran, Inc.; Burtonsville MD USA
| | - Mark D. Szarowicz
- Translational Gerontology Branch; National Institute on Aging; NIH; Baltimore MD USA
- SoBran, Inc.; Burtonsville MD USA
| | - Rafael de Cabo
- Translational Gerontology Branch; National Institute on Aging; NIH; Baltimore MD USA
| | - Julie A. Mattison
- Translational Gerontology Branch; National Institute on Aging; NIH; Baltimore MD USA
| | - Gregorio Valdez
- Virginia Tech Carilion Research Institute; Virginia Tech; Roanoke VA USA
- Department of Biological Sciences; Virginia Tech; Blacksburg VA USA
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Segura-Aguilar J, Huenchuguala S. Aminochrome Induces Irreversible Mitochondrial Dysfunction by Inducing Autophagy Dysfunction in Parkinson's Disease. Front Neurosci 2018; 12:106. [PMID: 29593482 PMCID: PMC5859232 DOI: 10.3389/fnins.2018.00106] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Accepted: 02/12/2018] [Indexed: 01/21/2023] Open
Affiliation(s)
- Juan Segura-Aguilar
- Molecular and Clinical Pharmacology, Faculty of Medicine, Instituto de Ciencias Biomédicas (ICBM), University of Chile, Santiago, Chile
| | - Sandro Huenchuguala
- Departamento de Ciencias Biológicas y Químicas, Facultad de Ciencia, Universidad San Sebastián, Puerto Montt, Chile
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Agim ZS, Cannon JR. Alterations in the nigrostriatal dopamine system after acute systemic PhIP exposure. Toxicol Lett 2018; 287:31-41. [PMID: 29378243 DOI: 10.1016/j.toxlet.2018.01.017] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Revised: 01/10/2018] [Accepted: 01/23/2018] [Indexed: 11/30/2022]
Abstract
Heterocyclic amines (HCAs) are primarily formed during cooking of meat at high temperature. HCAs have been extensively studied as mutagens and possible carcinogens. Emerging data suggest that HCAs are neurotoxic and may be relevant to Parkinson's disease (PD) etiology. However, the majority of HCAs have not been evaluated for in vivo neurotoxicity. Here, we investigated acute in vivo neurotoxicity of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP). PhIP is the most prevalent genotoxin in many types of meats. Adult, male Sprague-Dawley rats were subjected to acute, systemic PhIP at doses and time-points that have been extensively utilized in cancer studies (100 and 200 mg/kg for 8, 24 h) and evaluated for changes in dopaminergic, serotoninergic, GABAergic, and glutamatergic neurotransmission. PhIP exposure resulted in decreased striatal dopamine metabolite levels and dopamine turnover in the absence of changes to vesicular monoamine transporter 2 levels; other neurotransmitter systems were unaffected. Quantification of intracellular nitrotyrosine revealed higher levels of oxidative damage in dopaminergic neurons in the substantia nigra after PhIP exposure, while other neuronal populations were less sensitive. These changes occurred in the absence of an overt lesion to the nigrostriatal dopamine system. Collectively, our study suggests that acute PhIP treatment in vivo targets the nigrostriatal dopaminergic system and that PhIP should be further examined in chronic, low-dose studies for PD relevance.
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Affiliation(s)
- Zeynep Sena Agim
- School of Health Sciences, Purdue University, West Lafayette, IN 47907, United States; Purdue Institute for Integrative Neurosciences, Purdue University, West Lafayette, IN 47907, United States.
| | - Jason R Cannon
- School of Health Sciences, Purdue University, West Lafayette, IN 47907, United States; Purdue Institute for Integrative Neurosciences, Purdue University, West Lafayette, IN 47907, United States.
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Segura-Aguilar J. Neurotoxins as Preclinical Models for Parkinson's Disease. Neurotox Res 2018; 34:870-877. [PMID: 29313219 DOI: 10.1007/s12640-017-9856-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Revised: 12/13/2017] [Accepted: 12/18/2017] [Indexed: 12/21/2022]
Abstract
Translational medicine is one of the major concerns in this century. While significant advances have been made with scientific knowledge, the translation of their promising results has not led to any new therapies. In Parkinson's disease, a long list of clinical studies, based on preclinical models with exogenous neurotoxins, has failed. Therefore, the aim of this opinion paper is to open discussion about preclinical models for Parkinson's disease based on neurotoxins.
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Affiliation(s)
- Juan Segura-Aguilar
- Department of Molecular and Clinical Pharmacology, Faculty of Medicine, University of Chile, Santiago, Chile.
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46
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Rizzi G, Tan KR. Dopamine and Acetylcholine, a Circuit Point of View in Parkinson's Disease. Front Neural Circuits 2017; 11:110. [PMID: 29311846 PMCID: PMC5744635 DOI: 10.3389/fncir.2017.00110] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2017] [Accepted: 12/14/2017] [Indexed: 12/30/2022] Open
Abstract
Data from the World Health Organization (National Institute on Aging, 2011) and the National Institutes of Health (He et al., 2016) predicts that while today the worldwide population over 65 years of age is estimated around 8.5%, this number will reach an astounding 17% by 2050. In this framework, solving current neurodegenerative diseases primarily associated with aging becomes more pressing than ever. In 2017, we celebrate a grim 200th anniversary since the very first description of Parkinson’s disease (PD) and its related symptomatology. Two centuries after this debilitating disease was first identified, finding a cure remains a hopeful goal rather than an attainable objective on the horizon. Tireless work has provided insight into the characterization and progression of the disease down to a molecular level. We now know that the main motor deficits associated with PD arise from the almost total loss of dopaminergic cells in the substantia nigra pars compacta. A concomitant loss of cholinergic cells entails a cognitive decline in these patients, and current therapies are only partially effective, often inducing side-effects after a prolonged treatment. This review covers some of the recent developments in the field of Basal Ganglia (BG) function in physiology and pathology, with a particular focus on the two main neuromodulatory systems known to be severely affected in PD, highlighting some of the remaining open question from three main stand points: - Heterogeneity of midbrain dopamine neurons. - Pairing of dopamine (DA) sub-circuits. - Dopamine-Acetylcholine (ACh) interaction. A vast amount of knowledge has been accumulated over the years from experimental conditions, but very little of it is reflected or used at a translational or clinical level. An initiative to implement the knowledge that is emerging from circuit-based approaches to tackle neurodegenerative disorders like PD will certainly be tremendously beneficial.
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Affiliation(s)
| | - Kelly R Tan
- Biozentrum, University of Basel, Basel, Switzerland
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Ito H, Kawaguchi H, Kodaka F, Takuwa H, Ikoma Y, Shimada H, Kimura Y, Seki C, Kubo H, Ishii S, Takano H, Suhara T. Normative data of dopaminergic neurotransmission functions in substantia nigra measured with MRI and PET: Neuromelanin, dopamine synthesis, dopamine transporters, and dopamine D2 receptors. Neuroimage 2017; 158:12-17. [DOI: 10.1016/j.neuroimage.2017.06.066] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Revised: 06/20/2017] [Accepted: 06/23/2017] [Indexed: 10/19/2022] Open
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Zucca FA, Segura-Aguilar J, Ferrari E, Muñoz P, Paris I, Sulzer D, Sarna T, Casella L, Zecca L. Interactions of iron, dopamine and neuromelanin pathways in brain aging and Parkinson's disease. Prog Neurobiol 2017; 155:96-119. [PMID: 26455458 PMCID: PMC4826627 DOI: 10.1016/j.pneurobio.2015.09.012] [Citation(s) in RCA: 415] [Impact Index Per Article: 59.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Revised: 09/14/2015] [Accepted: 09/17/2015] [Indexed: 12/11/2022]
Abstract
There are several interrelated mechanisms involving iron, dopamine, and neuromelanin in neurons. Neuromelanin accumulates during aging and is the catecholamine-derived pigment of the dopamine neurons of the substantia nigra and norepinephrine neurons of the locus coeruleus, the two neuronal populations most targeted in Parkinson's disease. Many cellular redox reactions rely on iron, however an altered distribution of reactive iron is cytotoxic. In fact, increased levels of iron in the brain of Parkinson's disease patients are present. Dopamine accumulation can induce neuronal death; however, excess dopamine can be removed by converting it into a stable compound like neuromelanin, and this process rescues the cell. Interestingly, the main iron compound in dopamine and norepinephrine neurons is the neuromelanin-iron complex, since neuromelanin is an effective metal chelator. Neuromelanin serves to trap iron and provide neuronal protection from oxidative stress. This equilibrium between iron, dopamine, and neuromelanin is crucial for cell homeostasis and in some cellular circumstances can be disrupted. Indeed, when neuromelanin-containing organelles accumulate high load of toxins and iron during aging a neurodegenerative process can be triggered. In addition, neuromelanin released by degenerating neurons activates microglia and the latter cause neurons death with further release of neuromelanin, then starting a self-propelling mechanism of neuroinflammation and neurodegeneration. Considering the above issues, age-related accumulation of neuromelanin in dopamine neurons shows an interesting link between aging and neurodegeneration.
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Affiliation(s)
- Fabio A Zucca
- Institute of Biomedical Technologies, National Research Council of Italy, Segrate, Milan, Italy
| | - Juan Segura-Aguilar
- Faculty of Medicine, Molecular and Clinical Pharmacology, ICBM, University of Chile, Santiago, Chile
| | - Emanuele Ferrari
- Institute of Biomedical Technologies, National Research Council of Italy, Segrate, Milan, Italy
| | - Patricia Muñoz
- Faculty of Medicine, Molecular and Clinical Pharmacology, ICBM, University of Chile, Santiago, Chile
| | - Irmgard Paris
- Faculty of Medicine, Molecular and Clinical Pharmacology, ICBM, University of Chile, Santiago, Chile; Department of Basic Sciences, Faculty of Sciences, Santo Tomás University, Viña del Mar, Chile
| | - David Sulzer
- Department of Psychiatry, Columbia University Medical Center, New York, NY, USA; Department of Neurology, Columbia University Medical Center, New York, NY, USA; Department of Pharmacology, Columbia University Medical Center, New York, NY, USA
| | - Tadeusz Sarna
- Department of Biophysics, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland
| | - Luigi Casella
- Department of Chemistry, University of Pavia, Pavia, Italy
| | - Luigi Zecca
- Institute of Biomedical Technologies, National Research Council of Italy, Segrate, Milan, Italy.
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Smith ES, Clark ME, Hardy GA, Kraan DJ, Biondo E, Gonzalez-Lima F, Cormack LK, Monfils M, Lee HJ. Daily consumption of methylene blue reduces attentional deficits and dopamine reduction in a 6-OHDA model of Parkinson's disease. Neuroscience 2017; 359:8-16. [PMID: 28694175 DOI: 10.1016/j.neuroscience.2017.07.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Revised: 06/01/2017] [Accepted: 07/02/2017] [Indexed: 01/05/2023]
Abstract
Recently, alternative drug therapies for Parkinson's disease (PD) have been investigated as there are many shortcomings of traditional dopamine-based therapies including difficulties in treating cognitive and attentional dysfunction. A promising therapeutic avenue is to target mitochondrial dysfunction and oxidative stress in PD. One option might be the use of methylene blue (MB), an antioxidant and metabolic enhancer. MB has been shown to improve cognitive function in both intact rodents and rodent disease models. Therefore, we investigated whether MB might treat attentional deficits in a rat model of PD induced by 6-hydroxydopamine (6-OHDA). MB also has neuroprotective capabilities against neurotoxic insult, so we also assessed the ability of MB to provide neuroprotection in our PD model. The results show that MB could preserve some dopamine neurons in the substantia nigra par compacta when 6-OHDA was infused into the medial forebrain bundle. This neuroprotection did not yield a significant behavioral improvement when motor functions were measured. However, MB significantly improved attentional performance in the five-choice task designed to measure selective and sustained attention. In conclusion, MB might be useful in improving some attentional function and preserving dopaminergic cells in this model. Future work should continue to study and optimize the abilities of MB for the treatment of PD.
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Affiliation(s)
- Elizabeth S Smith
- The University of Texas at Austin, Department of Psychology, United States
| | - Madeline E Clark
- The University of Texas at Austin, Department of Psychology, United States
| | - Gwendolyn A Hardy
- The University of Texas at Austin, Department of Psychology, United States
| | - David J Kraan
- The University of Texas at Austin, Department of Psychology, United States
| | - Elisa Biondo
- The University of Texas at Austin, Department of Psychology, United States
| | - F Gonzalez-Lima
- The University of Texas at Austin, Department of Psychology, United States
| | - Lawrence K Cormack
- The University of Texas at Austin, Department of Psychology, United States
| | - Marie Monfils
- The University of Texas at Austin, Department of Psychology, United States
| | - Hongjoo J Lee
- The University of Texas at Austin, Department of Psychology, United States.
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50
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Segura-Aguilar J. On the role of endogenous neurotoxins and neuroprotection in Parkinson's disease. Neural Regen Res 2017; 12:897-901. [PMID: 28761417 PMCID: PMC5514859 DOI: 10.4103/1673-5374.208560] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/15/2017] [Indexed: 11/30/2022] Open
Abstract
For 50 years ago was introduced L-3,4-dihydroxyphenylalanine (L-dopa) in Parkinson's disease treatment and during this significant advances has been done but what trigger the degeneration of the nigrostriatal system remain unknown. There is a general agreement in the scientific community that mitochondrial dysfunction, protein degradation dysfunction, alpha-synuclein aggregation to neurotoxic oligomers, neuroinflammation, oxidative and endoplasmic reticulum stress are involved in the loss of dopaminergic neurons containing neuromelanin in Parkinson's disease. The question is what triggers these mechanisms. The age of normal onset in idiopathic Parkinson's disease suggests that environmental factors such as metals, pollutants or genetic mutations cannot be involved because these factors are related to early onset of Parkinsonism. Therefore, we have to search for endogenous neurotoxins and neuroprotection in order to understand what trigger the loss of dopaminergic neurons. One important feature of Parkinson's disease is the rate of the degenerative process before the motor symptoms are evident and during the disease progression. The extremely slow rate of Parkinson's disease suggests that the neurotoxins and the neuroprotection have to be related to dopamine metabolism. Possible candidates for endogenous neurotoxins are alpha-synuclein neurotoxic oligomers, 4-dihydroxyphenylacetaldehyde and ortho-quinones formed during dopamine oxidation to neuromelanin. Vesicular monoamine transporter-2, DT-diaphorase and glutathione transferase M2-2 seems to be the most important neuroprotective mechanism to prevent neurotoxic mechanism during dopamine oxidation.
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Affiliation(s)
- Juan Segura-Aguilar
- Molecular and Clinical Pharmacology, ICBM, Faculty of Medicine, University of Chile, Santiago, Chile
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