1
|
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.
Collapse
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.
| |
Collapse
|
2
|
Bucher ML, Dunn AR, Bradner JM, Egerton KS, Burkett JP, Johnson MA, Miller GW. Synaptic vesicle glycoprotein 2C enhances vesicular storage of dopamine and counters dopaminergic toxicity. Eur J Neurosci 2024; 59:2483-2501. [PMID: 38532289 DOI: 10.1111/ejn.16311] [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: 06/20/2023] [Revised: 02/14/2024] [Accepted: 02/22/2024] [Indexed: 03/28/2024]
Abstract
Dopaminergic neurons of the substantia nigra exist in a persistent state of vulnerability resulting from high baseline oxidative stress, high-energy demand, and broad unmyelinated axonal arborisations. Impairments in the storage of dopamine compound this stress because of cytosolic reactions that transform the vital neurotransmitter into an endogenous neurotoxicant, and this toxicity is thought to contribute to the dopamine neuron degeneration that occurs Parkinson's disease. We have previously identified synaptic vesicle glycoprotein 2C (SV2C) as a modifier of vesicular dopamine function, demonstrating that genetic ablation of SV2C in mice results in decreased dopamine content and evoked dopamine release in the striatum. Here, we adapted a previously published in vitro assay utilising false fluorescent neurotransmitter 206 (FFN206) to visualise how SV2C regulates vesicular dopamine dynamics and determined that SV2C promotes the uptake and retention of FFN206 within vesicles. In addition, we present data indicating that SV2C enhances the retention of dopamine in the vesicular compartment with radiolabelled dopamine in vesicles isolated from immortalised cells and from mouse brain. Further, we demonstrate that SV2C enhances the ability of vesicles to store the neurotoxicant 1-methyl-4-phenylpyridinium (MPP+) and that genetic ablation of SV2C results in enhanced 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced vulnerability in mice. Together, these findings suggest that SV2C functions to enhance vesicular storage of dopamine and neurotoxicants and helps maintain the integrity of dopaminergic neurons.
Collapse
Affiliation(s)
- Meghan L Bucher
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, New York, USA
| | - Amy R Dunn
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA
- The Jackson Laboratory, Bar Harbor, Maine, USA
| | - Joshua M Bradner
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, New York, USA
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA
- AbbVie CRC, Cambridge, Massachusetts, USA
| | - Kristen Stout Egerton
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA
- School of Education and Health Sciences, North Central College, Naperville, Illinois, USA
| | - James P Burkett
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA
- Department of Neurosciences, University of Toledo College of Medicine, Toledo, Ohio, USA
| | - Michelle A Johnson
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA
- College of Arts and Sciences, Oberlin College, Oberlin, Ohio, USA
| | - Gary W Miller
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, New York, USA
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA
- Department of Molecular Pharmacology and Therapeutics, Vagelos College of Physicians and Surgeons, Columbia University, New York, New York, USA
| |
Collapse
|
3
|
Bucher ML, Dunn AR, Bradner JM, Egerton KS, Burkett JP, Johnson MA, Miller GW. Synaptic vesicle glycoprotein 2C enhances vesicular storage of dopamine and counters dopaminergic toxicity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.26.546143. [PMID: 37425736 PMCID: PMC10326994 DOI: 10.1101/2023.06.26.546143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/11/2023]
Abstract
Dopaminergic neurons of the substantia nigra exist in a persistent state of vulnerability resulting from high baseline oxidative stress, high energy demand, and broad unmyelinated axonal arborizations. Impairments in the storage of dopamine compound this stress due to cytosolic reactions that transform the vital neurotransmitter into an endogenous neurotoxicant, and this toxicity is thought to contribute to the dopamine neuron degeneration that occurs Parkinson's disease. We have previously identified synaptic vesicle glycoprotein 2C (SV2C) as a modifier of vesicular dopamine function, demonstrating that genetic ablation of SV2C in mice results in decreased dopamine content and evoked dopamine release in the striatum. Here, we adapted a previously published in vitro assay utilizing false fluorescent neurotransmitter 206 (FFN206) to visualize how SV2C regulates vesicular dopamine dynamics and determined that SV2C promotes the uptake and retention of FFN206 within vesicles. In addition, we present data indicating that SV2C enhances the retention of dopamine in the vesicular compartment with radiolabeled dopamine in vesicles isolated from immortalized cells and from mouse brain. Further, we demonstrate that SV2C enhances the ability of vesicles to store the neurotoxicant 1-methyl-4-phenylpyridinium (MPP+) and that genetic ablation of SV2C results in enhanced 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced vulnerability in mice. Together, these findings suggest that SV2C functions to enhance vesicular storage of dopamine and neurotoxicants, and helps maintain the integrity of dopaminergic neurons.
Collapse
Affiliation(s)
- Meghan L Bucher
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY 10032, USA
| | - Amy R Dunn
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA
| | - Joshua M Bradner
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY 10032, USA
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA
| | - Kristen Stout Egerton
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA
| | - James P Burkett
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA
| | - Michelle A Johnson
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA
| | - Gary W Miller
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY 10032, USA
- Department of Molecular Pharmacology and Therapeutics, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY 10031, USA
| |
Collapse
|
4
|
Zeng F, Parker K, Zhan Y, Miller M, Zhu MY. Upregulated DNA Damage-Linked Biomarkers in Parkinson's Disease Model Mice. ASN Neuro 2023; 15:17590914231152099. [PMID: 36683340 PMCID: PMC9880594 DOI: 10.1177/17590914231152099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 12/31/2022] [Accepted: 01/03/2023] [Indexed: 01/24/2023] Open
Abstract
SUMMARY STATEMENT The present study examined expression of DNA damage markers in VMAT2 Lo PD model mice. The results demonstrate there is a significant increase in these DNA damage markers mostly in the brain regions of 18- and 23-month-old model mice, indicating oxidative stress-induced DNA lesion is an important pathologic feature of this mouse model.
Collapse
Affiliation(s)
- Fei Zeng
- Department of Neurology, Renmin Hospital of the Wuhan University,
Wuhan, China
- Departments of Biomedical Sciences, Quillen College of Medicine, East Tennessee State
University, Johnson City, TN, USA
| | - Karsten Parker
- Departments of Biomedical Sciences, Quillen College of Medicine, East Tennessee State
University, Johnson City, TN, USA
| | - Yanqiang Zhan
- Department of Neurology, Renmin Hospital of the Wuhan University,
Wuhan, China
- Departments of Biomedical Sciences, Quillen College of Medicine, East Tennessee State
University, Johnson City, TN, USA
| | - Matthew Miller
- Departments of Biomedical Sciences, Quillen College of Medicine, East Tennessee State
University, Johnson City, TN, USA
| | - Meng-Yang Zhu
- Departments of Biomedical Sciences, Quillen College of Medicine, East Tennessee State
University, Johnson City, TN, USA
| |
Collapse
|
5
|
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.
Collapse
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
| |
Collapse
|
6
|
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
|
7
|
Du Y, Choi S, Pilski A, Graves SM. Differential vulnerability of locus coeruleus and dorsal raphe neurons to chronic methamphetamine-induced degeneration. Front Cell Neurosci 2022; 16:949923. [PMID: 35936499 PMCID: PMC9354074 DOI: 10.3389/fncel.2022.949923] [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: 05/21/2022] [Accepted: 07/04/2022] [Indexed: 12/15/2022] Open
Abstract
Methamphetamine (meth) increases monoamine oxidase (MAO)-dependent mitochondrial stress in axons of substantia nigra pars compacta (SNc), and ventral tegmental area (VTA) dopamine neurons. Chronic administration of meth results in SNc degeneration and MAO inhibition is neuroprotective, whereas, the VTA is resistant to degeneration. This differential vulnerability is attributed, at least in part, to the presence of L-type Ca2+ channel-dependent mitochondrial stress in SNc but not VTA dopamine neurons. MAO is also expressed in other monoaminergic neurons such as noradrenergic locus coeruleus (LC) and serotonergic dorsal raphe (DR) neurons. The impact of meth on mitochondrial stress in LC and DR neurons is unknown. In the current study we used a genetically encoded redox biosensor to investigate meth-induced MAO-dependent mitochondrial stress in LC and DR neurons. Similar to SNc and VTA neurons, meth increased MAO-dependent mitochondrial stress in axonal but not somatic compartments of LC norepinephrine and DR serotonin neurons. Chronic meth administration (5 mg/kg; 28-day) resulted in degeneration of LC neurons and MAO inhibition was neuroprotective whereas DR neurons were resistant to degeneration. Activating L-type Ca2+ channels increased mitochondrial stress in LC but not DR axons and inhibiting L-type Ca2+ channels in vivo with isradipine prevented meth-induced LC degeneration. These data suggest that similar to recent findings in SNc and VTA dopamine neurons, the differential vulnerability between LC and DR neurons can be attributed to the presence of L-type Ca2+ channel-dependent mitochondrial stress. Taken together, the present study demonstrates that both meth-induced MAO- and L-type Ca2+ channel-dependent mitochondrial stress are necessary for chronic meth-induced neurodegeneration.
Collapse
|
8
|
Rai SN, Singh P, Varshney R, Chaturvedi VK, Vamanu E, Singh MP, Singh BK. Promising drug targets and associated therapeutic interventions in Parkinson's disease. Neural Regen Res 2021; 16:1730-1739. [PMID: 33510062 PMCID: PMC8328771 DOI: 10.4103/1673-5374.306066] [Citation(s) in RCA: 66] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 10/26/2020] [Accepted: 12/17/2020] [Indexed: 12/11/2022] Open
Abstract
Parkinson's disease (PD) is one of the most debilitating brain diseases. Despite the availability of symptomatic treatments, response towards the health of PD patients remains scarce. To fulfil the medical needs of the PD patients, an efficacious and etiological treatment is required. In this review, we have compiled the information covering limitations of current therapeutic options in PD, novel drug targets for PD, and finally, the role of some critical beneficial natural products to control the progression of PD.
Collapse
Affiliation(s)
| | - Payal Singh
- Department of Zoology, Institute of Science, Banaras Hindu University, Varanasi, India
| | - Ritu Varshney
- Department of Bioengineering and Chemistry, Indian Institute of Technology Gandhinagar, Palaj, Gujarat, India
| | | | - Emanuel Vamanu
- Faculty of Biotechnology, University of Agronomic Science and Veterinary Medicine, Bucharest, Romania
| | - M. P. Singh
- Centre of Biotechnology, University of Allahabad, Prayagraj, India
| | - Brijesh Kumar Singh
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY, USA
| |
Collapse
|
9
|
Kang SS, Ahn EH, Liu X, Bryson M, Miller GW, Weinshenker D, Ye K. ApoE4 inhibition of VMAT2 in the locus coeruleus exacerbates Tau pathology in Alzheimer's disease. Acta Neuropathol 2021; 142:139-158. [PMID: 33895869 DOI: 10.1007/s00401-021-02315-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 04/08/2021] [Accepted: 04/17/2021] [Indexed: 01/20/2023]
Abstract
ApoE4 enhances Tau neurotoxicity and promotes the early onset of AD. Pretangle Tau in the noradrenergic locus coeruleus (LC) is the earliest detectable AD-like pathology in the human brain. However, a direct relationship between ApoE4 and Tau in the LC has not been identified. Here we show that ApoE4 selectively binds to the vesicular monoamine transporter 2 (VMAT2) and inhibits neurotransmitter uptake. The exclusion of norepinephrine (NE) from synaptic vesicles leads to its oxidation into the toxic metabolite 3,4-dihydroxyphenyl glycolaldehyde (DOPEGAL), which subsequently activates cleavage of Tau at N368 by asparagine endopeptidase (AEP) and triggers LC neurodegeneration. Our data reveal that ApoE4 boosts Tau neurotoxicity via VMAT2 inhibition, reduces hippocampal volume, and induces cognitive dysfunction in an AEP- and Tau N368-dependent manner, while conversely ApoE3 binds Tau and protects it from cleavage. Thus, ApoE4 exacerbates Tau neurotoxicity by increasing VMAT2 vesicle leakage and facilitating AEP-mediated Tau proteolytic cleavage in the LC via DOPEGAL.
Collapse
Affiliation(s)
- Seong Su Kang
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, 615 Michael St. Whitehead BLDG Room #141, Atlanta, GA, 30322, USA
| | - Eun Hee Ahn
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, 615 Michael St. Whitehead BLDG Room #141, Atlanta, GA, 30322, USA
| | - Xia Liu
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, 615 Michael St. Whitehead BLDG Room #141, Atlanta, GA, 30322, USA
| | - Matthew Bryson
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, 615 Michael St. Whitehead BLDG Room #141, Atlanta, GA, 30322, USA
| | - Gary W Miller
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, USA
| | - David Weinshenker
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Keqiang Ye
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, 615 Michael St. Whitehead BLDG Room #141, Atlanta, GA, 30322, USA.
| |
Collapse
|
10
|
Limanaqi F, Busceti CL, Celli R, Biagioni F, Fornai F. Autophagy as a gateway for the effects of methamphetamine: From neurotransmitter release and synaptic plasticity to psychiatric and neurodegenerative disorders. Prog Neurobiol 2021; 204:102112. [PMID: 34171442 DOI: 10.1016/j.pneurobio.2021.102112] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 02/27/2021] [Accepted: 06/18/2021] [Indexed: 02/07/2023]
Abstract
As a major eukaryotic cell clearing machinery, autophagy grants cell proteostasis, which is key for neurotransmitter release, synaptic plasticity, and neuronal survival. In line with this, besides neuropathological events, autophagy dysfunctions are bound to synaptic alterations that occur in mental disorders, and early on, in neurodegenerative diseases. This is also the case of methamphetamine (METH) abuse, which leads to psychiatric disturbances and neurotoxicity. While consistently altering the autophagy machinery, METH produces behavioral and neurotoxic effects through molecular and biochemical events that can be recapitulated by autophagy blockade. These consist of altered physiological dopamine (DA) release, abnormal stimulation of DA and glutamate receptors, as well as oxidative, excitotoxic, and neuroinflammatory events. Recent molecular insights suggest that METH early impairs the autophagy machinery, though its functional significance remains to be investigated. Here we discuss evidence suggesting that alterations of DA transmission and autophagy are intermingled within a chain of events underlying behavioral alterations and neurodegenerative phenomena produced by METH. Understanding how METH alters the autophagy machinery is expected to provide novel insights into the neurobiology of METH addiction sharing some features with psychiatric disorders and parkinsonism.
Collapse
Affiliation(s)
- Fiona Limanaqi
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Via Roma, 55, 56126, Pisa, PI, Italy
| | | | - Roberta Celli
- IRCCS Neuromed, Via Atinense 18, 86077 Pozzilli, IS, Italy
| | | | - Francesco Fornai
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Via Roma, 55, 56126, Pisa, PI, Italy; IRCCS Neuromed, Via Atinense 18, 86077 Pozzilli, IS, Italy.
| |
Collapse
|
11
|
Vecchio LM, Sullivan P, Dunn AR, Bermejo MK, Fu R, Masoud ST, Gregersen E, Urs NM, Nazari R, Jensen PH, Ramsey A, Goldstein DS, Miller GW, Salahpour A. Enhanced tyrosine hydroxylase activity induces oxidative stress, causes accumulation of autotoxic catecholamine metabolites, and augments amphetamine effects in vivo. J Neurochem 2021; 158:960-979. [PMID: 33991113 PMCID: PMC8376767 DOI: 10.1111/jnc.15432] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 05/10/2021] [Accepted: 05/10/2021] [Indexed: 12/12/2022]
Abstract
In Parkinson's disease, dopamine‐containing nigrostriatal neurons undergo profound degeneration. Tyrosine hydroxylase (TH) is the rate‐limiting enzyme in dopamine biosynthesis. TH increases in vitro formation of reactive oxygen species, and previous animal studies have reported links between cytosolic dopamine build‐up and oxidative stress. To examine effects of increased TH activity in catecholaminergic neurons in vivo, we generated TH‐over‐expressing mice (TH‐HI) using a BAC‐transgenic approach that results in over‐expression of TH with endogenous patterns of expression. The transgenic mice were characterized by western blot, qPCR, and immunohistochemistry. Tissue contents of dopamine, its metabolites, and markers of oxidative stress were evaluated. TH‐HI mice had a 3‐fold increase in total and phosphorylated TH levels and an increased rate of dopamine synthesis. Coincident with elevated dopamine turnover, TH‐HI mice showed increased striatal production of H2O2 and reduced glutathione levels. In addition, TH‐HI mice had elevated striatal levels of the neurotoxic dopamine metabolites 3,4‐dihydroxyphenylacetaldehyde and 5‐S‐cysteinyl‐dopamine and were more susceptible than wild‐type mice to the effects of amphetamine and methamphetamine. These results demonstrate that increased TH alone is sufficient to produce oxidative stress in vivo, build up autotoxic dopamine metabolites, and augment toxicity.
Collapse
Affiliation(s)
- Laura M Vecchio
- Department of Pharmacology and Toxicology, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Patricia Sullivan
- Autonomic Medicine Section, Clinical Neurosciences Program, Division of Intramural Research, National Institute of Neurological, Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Amy R Dunn
- The Jackson Laboratory. Bar Harbor, Maine, USA
| | - Marie Kristel Bermejo
- Department of Pharmacology and Toxicology, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Rong Fu
- Department of Pharmacology, Emory University School of Medicine, Atlanta, GA, USA
| | - Shababa T Masoud
- Department of Pharmacology and Toxicology, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Emil Gregersen
- Danish Research Institute of Translational Neuroscience - DANDRITE, Department of Biomedicine, Faculty of Health, Aarhus University, Aarhus C., Denmark
| | - Nikhil M Urs
- Department of Pharmacology and Therapeutics, University of Florida, Gainsville, FL, USA
| | - Reza Nazari
- Department of Pharmacology and Toxicology, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Poul Henning Jensen
- Danish Research Institute of Translational Neuroscience - DANDRITE, Department of Biomedicine, Faculty of Health, Aarhus University, Aarhus C., Denmark
| | - Amy Ramsey
- Department of Pharmacology and Toxicology, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - David S Goldstein
- Autonomic Medicine Section, Clinical Neurosciences Program, Division of Intramural Research, National Institute of Neurological, Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Gary W Miller
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University Medical Centre, New York, NY, USA
| | - Ali Salahpour
- Department of Pharmacology and Toxicology, Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| |
Collapse
|
12
|
Goldstein DS. The Catecholaldehyde Hypothesis for the Pathogenesis of Catecholaminergic Neurodegeneration: What We Know and What We Do Not Know. Int J Mol Sci 2021; 22:ijms22115999. [PMID: 34206133 PMCID: PMC8199574 DOI: 10.3390/ijms22115999] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 05/25/2021] [Accepted: 05/28/2021] [Indexed: 01/10/2023] Open
Abstract
3,4-Dihydroxyphenylacetaldehyde (DOPAL) is the focus of the catecholaldehyde hypothesis for the pathogenesis of Parkinson’s disease and other Lewy body diseases. The catecholaldehyde is produced via oxidative deamination catalyzed by monoamine oxidase (MAO) acting on cytoplasmic dopamine. DOPAL is autotoxic, in that it can harm the same cells in which it is produced. Normally, DOPAL is detoxified by aldehyde dehydrogenase (ALDH)-mediated conversion to 3,4-dihydroxyphenylacetic acid (DOPAC), which rapidly exits the neurons. Genetic, environmental, or drug-induced manipulations of ALDH that build up DOPAL promote catecholaminergic neurodegeneration. A concept derived from the catecholaldehyde hypothesis imputes deleterious interactions between DOPAL and the protein alpha-synuclein (αS), a major component of Lewy bodies. DOPAL potently oligomerizes αS, and αS oligomers impede vesicular and mitochondrial functions, shifting the fate of cytoplasmic dopamine toward the MAO-catalyzed formation of DOPAL—destabilizing vicious cycles. Direct and indirect effects of DOPAL and of DOPAL-induced misfolded proteins could “freeze” intraneuronal reactions, plasticity of which is required for neuronal homeostasis. The extent to which DOPAL toxicity is mediated by interactions with αS, and vice versa, is poorly understood. Because of numerous secondary effects such as augmented spontaneous oxidation of dopamine by MAO inhibition, there has been insufficient testing of the catecholaldehyde hypothesis in animal models. The clinical pathophysiological significance of genetics, emotional stress, environmental agents, and interactions with numerous proteins relevant to the catecholaldehyde hypothesis are matters for future research. The imposing complexity of intraneuronal catecholamine metabolism seems to require a computational modeling approach to elucidate clinical pathogenetic mechanisms and devise pathophysiology-based, individualized treatments.
Collapse
Affiliation(s)
- David S Goldstein
- Autonomic Medicine Section, Clinical Neurosciences Program, Division of Intramural Research, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| |
Collapse
|
13
|
Cui K, Yang F, Tufan T, Raza MU, Zhan Y, Fan Y, Zeng F, Brown RW, Price JB, Jones TC, Miller GW, Zhu MY. Restoration of Noradrenergic Function in Parkinson's Disease Model Mice. ASN Neuro 2021; 13:17590914211009730. [PMID: 33940943 PMCID: PMC8114769 DOI: 10.1177/17590914211009730] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Dysfunction of the central noradrenergic and dopaminergic systems is the primary neurobiological characteristic of Parkinson’s disease (PD). Importantly, neuronal loss in the locus coeruleus (LC) that occurs in early stages of PD may accelerate progressive loss of dopaminergic neurons. Therefore, restoring the activity and function of the deficient noradrenergic system may be an important therapeutic strategy for early PD. In the present study, the lentiviral constructions of transcription factors Phox2a/2b, Hand2 and Gata3, either alone or in combination, were microinjected into the LC region of the PD model VMAT2 Lo mice at 12 and 18 month age. Biochemical analysis showed that microinjection of lentiviral expression cassettes into the LC significantly increased mRNA levels of Phox2a, and Phox2b, which were accompanied by parallel increases of mRNA and proteins of dopamine β-hydroxylase (DBH) and tyrosine hydroxylase (TH) in the LC. Furthermore, there was considerable enhancement of DBH protein levels in the frontal cortex and hippocampus, as well as enhanced TH protein levels in the striatum and substantia nigra. Moreover, these manipulations profoundly increased norepinephrine and dopamine concentrations in the striatum, which was followed by a remarkable improvement of the spatial memory and locomotor behavior. These results reveal that over-expression of these transcription factors in the LC improves noradrenergic and dopaminergic activities and functions in this rodent model of PD. It provides the necessary groundwork for the development of gene therapies of PD, and expands our understanding of the link between the LC-norepinephrine and dopamine systems during the progression of PD.
Collapse
Affiliation(s)
- Kui Cui
- Department of Biomedical Sciences, Quillen College of Medicine, East Tennessee State University, Johnson City, United States
| | - Fan Yang
- Department of Biomedical Sciences, Quillen College of Medicine, East Tennessee State University, Johnson City, United States.,Hong Kong Institute, Asia Metropolitan University, Hong Kong, China
| | - Turan Tufan
- Department of Biomedical Sciences, Quillen College of Medicine, East Tennessee State University, Johnson City, United States
| | - Muhammad U Raza
- Department of Biomedical Sciences, Quillen College of Medicine, East Tennessee State University, Johnson City, United States
| | - Yanqiang Zhan
- Department of Biomedical Sciences, Quillen College of Medicine, East Tennessee State University, Johnson City, United States.,Department of Neurology, Renmin Hospital of the Wuhan University, Wuhan, China
| | - Yan Fan
- Department of Biomedical Sciences, Quillen College of Medicine, East Tennessee State University, Johnson City, United States.,Department of Biochemistry, Nantong University College of Medicine, Nantong, China
| | - Fei Zeng
- Department of Biomedical Sciences, Quillen College of Medicine, East Tennessee State University, Johnson City, United States.,Department of Neurology, Renmin Hospital of the Wuhan University, Wuhan, China
| | - Russell W Brown
- Department of Biomedical Sciences, Quillen College of Medicine, East Tennessee State University, Johnson City, United States
| | - Jennifer B Price
- Department of Biological Sciences, College of Arts and Sciences; East Tennessee State University, Johnson City, United States
| | - Thomas C Jones
- Department of Biological Sciences, College of Arts and Sciences; East Tennessee State University, Johnson City, United States
| | - Gary W Miller
- Department of Environmental Health Sciences, Mailmen School of Public Health, Columbia University, New York, New York, United States
| | - Meng-Yang Zhu
- Department of Biomedical Sciences, Quillen College of Medicine, East Tennessee State University, Johnson City, United States
| |
Collapse
|
14
|
Bradner JM, Kalia V, Lau FK, Sharma M, Bucher ML, Johnson M, Chen M, Walker DI, Jones DP, Miller GW. Genetic or Toxicant-Induced Disruption of Vesicular Monoamine Storage and Global Metabolic Profiling in Caenorhabditis elegans. Toxicol Sci 2021; 180:313-324. [PMID: 33538833 PMCID: PMC8041460 DOI: 10.1093/toxsci/kfab011] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
The proper storage and release of monoamines contributes to a wide range of neuronal activity. Here, we examine the effects of altered vesicular monoamine transport in the nematode Caenorhabditis elegans. The gene cat-1 is responsible for the encoding of the vesicular monoamine transporter (VMAT) in C. elegans and is analogous to the mammalian vesicular monoamine transporter 2 (VMAT2). Our laboratory has previously shown that reduced VMAT2 activity confers vulnerability on catecholamine neurons in mice. The purpose of this article was to determine whether this function is conserved and to determine the impact of reduced VMAT activity in C. elegans. Here we show that deletion of cat-1/VMAT increases sensitivity to the neurotoxicant 1-methyl-4-phenylpyridinium (MPP+) as measured by enhanced degeneration of dopamine neurons. Reduced cat-1/VMAT also induces changes in dopamine-mediated behaviors. High-resolution mass spectrometry-based metabolomics in the whole organism reveals changes in amino acid metabolism, including tyrosine metabolism in the cat-1/VMAT mutants. Treatment with MPP+ disrupted tryptophan metabolism. Both conditions altered glycerophospholipid metabolism, suggesting a convergent pathway of neuronal dysfunction. Our results demonstrate the evolutionarily conserved nature of monoamine function in C. elegans and further suggest that high-resolution mass spectrometry-based metabolomics can be used in this model to study environmental and genetic contributors to complex human disease.
Collapse
Affiliation(s)
- Joshua M Bradner
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, New York 10032, USA
| | - Vrinda Kalia
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, New York 10032, USA
| | - Fion K Lau
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, New York 10032, USA
| | - Monica Sharma
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, New York 10032, USA
| | - Meghan L Bucher
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, New York 10032, USA
| | - Michelle Johnson
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia 30322, USA
| | - Merry Chen
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia 30322, USA
| | - Douglas I Walker
- Department of Environmental Medicine and Public Health, Icahn School of Medicine at Mount Sinai, New York, New York 10029, USA
| | - Dean P Jones
- Department of Medicine, School of Medicine, Emory University, Atlanta, Georgia 30303, USA
| | - Gary W Miller
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, New York 10032, USA
| |
Collapse
|
15
|
Bekdash RA. The Cholinergic System, the Adrenergic System and the Neuropathology of Alzheimer's Disease. Int J Mol Sci 2021; 22:ijms22031273. [PMID: 33525357 PMCID: PMC7865740 DOI: 10.3390/ijms22031273] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 01/23/2021] [Accepted: 01/25/2021] [Indexed: 12/16/2022] Open
Abstract
Neurodegenerative diseases are a major public health problem worldwide with a wide spectrum of symptoms and physiological effects. It has been long reported that the dysregulation of the cholinergic system and the adrenergic system are linked to the etiology of Alzheimer’s disease. Cholinergic neurons are widely distributed in brain regions that play a role in cognitive functions and normal cholinergic signaling related to learning and memory is dependent on acetylcholine. The Locus Coeruleus norepinephrine (LC-NE) is the main noradrenergic nucleus that projects and supplies norepinephrine to different brain regions. Norepinephrine has been shown to be neuroprotective against neurodegeneration and plays a role in behavior and cognition. Cholinergic and adrenergic signaling are dysregulated in Alzheimer’s disease. The degeneration of cholinergic neurons in nucleus basalis of Meynert in the basal forebrain and the degeneration of LC-NE neurons were reported in Alzheimer’s disease. The aim of this review is to describe current literature on the role of the cholinergic system and the adrenergic system (LC-NE) in the pathology of Alzheimer’s disease and potential therapeutic implications.
Collapse
Affiliation(s)
- Rola A Bekdash
- Department of Biological Sciences, Rutgers University, Newark, NJ 07102, USA
| |
Collapse
|
16
|
Autophagy status as a gateway for stress-induced catecholamine interplay in neurodegeneration. Neurosci Biobehav Rev 2021; 123:238-256. [PMID: 33497785 DOI: 10.1016/j.neubiorev.2021.01.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 01/08/2021] [Accepted: 01/09/2021] [Indexed: 12/13/2022]
Abstract
The catecholamine-containing brainstem nuclei locus coeruleus (LC) and ventral tegmental area (VTA) are critically involved in stress responses. Alterations of catecholamine systems during chronic stress may contribute to neurodegeneration, including cognitive decline. Stress-related catecholamine alterations, while contributing to anxiety and depression, might accelerate neuronal degeneration by increasing the formation of toxic dopamine and norepinephrine by-products. These, in turn, may impair proteostasis within a variety of cortical and subcortical areas. In particular, the molecular events governing neurotransmission, neuroplasticity, and proteostasis within LC and VTA affect a variety of brain areas. Therefore, we focus on alterations of autophagy machinery in these nuclei as a relevant trigger in this chain of events. In fact, these catecholamine-containing areas are mostly prone to autophagy-dependent neurodegeneration. Thus, we propose a dynamic hypothesis according to which stress-induced autophagy alterations within the LC-VTA network foster a cascade towards early neurodegeneration within these nuclei.
Collapse
|
17
|
Bucher ML, Barrett CW, Moon CJ, Mortimer AD, Burton EA, Greenamyre JT, Hastings TG. Acquired dysregulation of dopamine homeostasis reproduces features of Parkinson's disease. NPJ PARKINSONS DISEASE 2020; 6:34. [PMID: 33298952 PMCID: PMC7666186 DOI: 10.1038/s41531-020-00134-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 10/08/2020] [Indexed: 12/24/2022]
Abstract
The catecholamine neurotransmitter dopamine has the potential to act as an endogenous neurotoxin when its vesicular sequestration is dysregulated. Despite postmortem analyses from patients with Parkinson’s disease that demonstrate decreased vesicular sequestration of dopamine with a corresponding increase in dopamine metabolism, dopamine’s contribution to nigrostriatal dopaminergic degeneration in Parkinson’s disease has been debated. Here, we present a new in vivo model demonstrating the induction of Parkinson’s disease-associated pathogenic mechanisms of degeneration resulting from acquired dysregulation of dopamine sequestration in nigrostriatal dopaminergic neurons in adult rats. Utilizing adeno-associated virus (serotype 2), viral-mediated small-hairpin RNA interference of endogenous vesicular monoamine transporter 2 (VMAT2) expression resulted in a loss of VMAT2 protein expression in transduced dopaminergic cell bodies in the substantia nigra with a corresponding loss of VMAT2 protein within the striatal terminals. The loss of VMAT2 resulted in an accumulation of cytosolic dopamine and subsequent increased dopamine metabolism, deficits in dopamine-mediated behaviors, and degeneration of nigrostriatal dopaminergic neurons that was rescued through reintroduction of exogenous VMAT2, demonstrating that the toxicity was specific to the loss of VMAT2. Analysis of parkinsonian pathogenic mechanisms of degeneration identified oxidative damage, activation of Parkinson’s disease-associated kinase LRRK2, and the formation of aberrant α-synuclein. This model demonstrates that a progressive acquired loss of VMAT2 expression in adulthood is sufficient to induce Parkinson’s disease-associated pathogenic mechanisms of degeneration and provides a new model to further investigate the consequences of cytosolic dopamine.
Collapse
Affiliation(s)
- Meghan L Bucher
- Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, PA, USA.,Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.,Department of Neuroscience, University of Pittsburgh School of Arts and Sciences, Pittsburgh, PA, USA.,Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY, USA
| | - Caitlyn W Barrett
- Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, PA, USA.,Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Connor J Moon
- Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, PA, USA.,Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.,Department of Neuroscience, University of Pittsburgh School of Arts and Sciences, Pittsburgh, PA, USA
| | - Amanda D Mortimer
- Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, PA, USA.,Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Edward A Burton
- Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, PA, USA.,Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.,Geriatric Research, Education and Clinical Center, Pittsburgh VA Healthcare System, Pittsburgh, PA, USA
| | - J Timothy Greenamyre
- Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, PA, USA.,Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Teresa G Hastings
- Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, PA, USA. .,Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA. .,Department of Neuroscience, University of Pittsburgh School of Arts and Sciences, Pittsburgh, PA, USA.
| |
Collapse
|
18
|
Goldstein DS. The "Sick-but-not-Dead" Phenomenon Applied to Catecholamine Deficiency in Neurodegenerative Diseases. Semin Neurol 2020; 40:502-514. [PMID: 32906170 PMCID: PMC10680399 DOI: 10.1055/s-0040-1713874] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The catecholamines dopamine and norepinephrine are key central neurotransmitters that participate in many neurobehavioral processes and disease states. Norepinephrine is also the main neurotransmitter mediating regulation of the circulation by the sympathetic nervous system. Several neurodegenerative disorders feature catecholamine deficiency. The most common is Parkinson's disease (PD), in which putamen dopamine content is drastically reduced. PD also entails severely decreased myocardial norepinephrine content, a feature that characterizes two other Lewy body diseases-pure autonomic failure and dementia with Lewy bodies. It is widely presumed that tissue catecholamine depletion in these conditions results directly from loss of catecholaminergic neurons; however, as highlighted in this review, there are also important functional abnormalities in extant residual catecholaminergic neurons. We refer to this as the "sick-but-not-dead" phenomenon. The malfunctions include diminished dopamine biosynthesis via tyrosine hydroxylase (TH) and L-aromatic-amino-acid decarboxylase (LAAAD), inefficient vesicular sequestration of cytoplasmic catecholamines, and attenuated neuronal reuptake via cell membrane catecholamine transporters. A unifying explanation for catecholaminergic neurodegeneration is autotoxicity exerted by 3,4-dihydroxyphenylacetaldehyde (DOPAL), an obligate intermediate in cytoplasmic dopamine metabolism. In PD, putamen DOPAL is built up with respect to dopamine, associated with a vesicular storage defect and decreased aldehyde dehydrogenase activity. Probably via spontaneous oxidation, DOPAL potently oligomerizes and forms quinone-protein adducts with ("quinonizes") α-synuclein (AS), a major constituent in Lewy bodies, and DOPAL-induced AS oligomers impede vesicular storage. DOPAL also quinonizes numerous intracellular proteins and inhibits enzymatic activities of TH and LAAAD. Treatments targeting DOPAL formation and oxidation therefore might rescue sick-but-not-dead catecholaminergic neurons in Lewy body diseases.
Collapse
Affiliation(s)
- David S. Goldstein
- Autonomic Medicine Section, Clinical Neurosciences Program, Division of Intramural Research, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland
| |
Collapse
|
19
|
Branco RC, Burkett JP, Black CA, Winokur E, Elsworth W, Dhamsania RK, Lohr KM, Schroeder JP, Weinshenker D, Jovanovic T, Miller GW. Vesicular monoamine transporter 2 mediates fear behavior in mice. GENES, BRAIN, AND BEHAVIOR 2020; 19:e12634. [PMID: 31898856 PMCID: PMC8170828 DOI: 10.1111/gbb.12634] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 12/27/2019] [Accepted: 12/29/2019] [Indexed: 11/26/2022]
Abstract
A subset of people exposed to a traumatic event develops post-traumatic stress disorder (PTSD), which is associated with dysregulated fear behavior. Genetic variation in SLC18A2, the gene that encodes vesicular monoamine transporter 2 (VMAT2), has been reported to affect risk for the development of PTSD in humans. Here, we use transgenic mice that express either 5% (VMAT2-LO mice) or 200% (VMAT2-HI mice) of wild-type levels of VMAT2 protein. We report that VMAT2-LO mice have reduced VMAT2 protein in the hippocampus and amygdala, impaired monoaminergic vesicular storage capacity in both the striatum and frontal cortex, decreased monoamine metabolite abundance and a greatly reduced capacity to release dopamine upon stimulation. Furthermore, VMAT2-LO mice showed exaggerated cued and contextual fear expression, altered fear habituation, inability to discriminate threat from safety cues, altered startle response compared with wild-type mice and an anxiogenic-like phenotype, but displayed no deficits in social function. By contrast, VMAT2-HI mice exhibited increased VMAT2 protein throughout the brain, higher vesicular storage capacity and greater dopamine release upon stimulation compared with wild-type controls. Behaviorally, VMAT2-HI mice were similar to wild-type mice in most assays, with some evidence of a reduced anxiety-like responses. Together, these data show that presynaptic monoamine function mediates PTSD-like outcomes in our mouse model, and suggest a causal link between reduced VMAT2 expression and fear behavior, consistent with the correlational relationship between VMAT2 genotype and PTSD risk in humans. Targeting this system is a potential strategy for the development of pharmacotherapies for disorders like PTSD.
Collapse
Affiliation(s)
- Rachel C. Branco
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia
| | - James P. Burkett
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia
| | - Carlie A. Black
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia
| | - Emily Winokur
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia
| | - William Elsworth
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia
| | - Rohan K. Dhamsania
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia
| | - Kelly M. Lohr
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia
| | - Jason P. Schroeder
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia
| | - David Weinshenker
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia
| | - Tanja Jovanovic
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, Georgia
| | - Gary W. Miller
- Department of Environmental Health, Rollins School of Public Health, Department of Pharmacology, Department of Neurology, Center for Neurodegenerative Diseases, Emory University, Atlanta, Georgia
| |
Collapse
|
20
|
Jiang S, Berger S, Hu Y, Bartsch D, Tian Y. Alterations of the Motor and Olfactory Functions Related to Parkinson's Disease in Transgenic Mice With a VMAT2-Deficiency in Dopaminergic Neurons. Front Neurosci 2020; 14:356. [PMID: 32410942 PMCID: PMC7198702 DOI: 10.3389/fnins.2020.00356] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 03/24/2020] [Indexed: 12/26/2022] Open
Abstract
Parkinson's disease (PD) is one of the most common neurodegenerative diseases, with approximately six million people affected worldwide. Vesicular monoamine transporter 2 (VMAT2) dysfunction has recently become a hot topic in the pathophysiology of PD, and the advent of transgenic mice has also accelerated the development of behavioral studies in animal models. However, there are only a few systematic behavioral tests that embrace abundant motor and non-motor performance in a unique mutant mouse model which correspond to the varied symptoms observed in human PD. The aim of this study is to evaluate the responsibility of the unique reduction of dopamine in the varied motor and non-motor symptoms of PD via a transgenic mice model. We analyzed neurotransmitter concentrations in the brain tissue of 18-month-old mutant mice, with selective inactivation of one allele of Vmat2 in dopaminergic neurons (VMAT2DATcre-HET) to confirm the selective reduction of dopamine, and then examined behavioral functions. Neurochemical tests showed lower dopamine concentrations in specific brain regions of VMAT2DATcre-HET mice, especially the ventral tegmental area/substantia nigra and striatum, together with relatively unchanging concentrations of norepinephrine and serotonin, demonstrating the dopaminergic specificity of this mouse model. Behavioral tasks showed impairments in several motor functions and major defects in olfactory abilities in the VMAT2DATcre-HET mice. However, no significant changes were found in the majority of non-motor tests, such as emotional performance and sleep patterns. We concluded from this study that the selective inactivation of one allele of the Vmat2 gene in dopaminergic neurons was related to dopamine reduction, resulting in phenotypes resembling some of the major deficits in PD, especially those of motor symptoms and olfactory functions.
Collapse
Affiliation(s)
- Song Jiang
- Department of Neurology, First Affiliated Hospital of Anhui Medical University, Hefei, China.,Department of Molecular Biology, Central Institute of Mental Health, Heidelberg University Faculty of Medicine in Mannheim, Mannheim, Germany
| | - Stefan Berger
- Department of Molecular Biology, Central Institute of Mental Health, Heidelberg University Faculty of Medicine in Mannheim, Mannheim, Germany
| | - Yajuan Hu
- Department of Neurology, First Affiliated Hospital of Anhui Medical University, Hefei, China.,Anhui Province Key Laboratory of Cognition and Neuropsychiatric Disorders, Anhui Medical University, Hefei, China
| | - Dusan Bartsch
- Department of Molecular Biology, Central Institute of Mental Health, Heidelberg University Faculty of Medicine in Mannheim, Mannheim, Germany
| | - Yanghua Tian
- Department of Neurology, First Affiliated Hospital of Anhui Medical University, Hefei, China.,Anhui Province Key Laboratory of Cognition and Neuropsychiatric Disorders, Anhui Medical University, Hefei, China.,Collaborative Innovation Center of Neuropsychiatric Disorders and Mental Health, Hefei, China
| |
Collapse
|
21
|
Goldstein DS. The catecholaldehyde hypothesis: where MAO fits in. J Neural Transm (Vienna) 2020; 127:169-177. [PMID: 31807952 PMCID: PMC10680281 DOI: 10.1007/s00702-019-02106-9] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 11/14/2019] [Indexed: 12/13/2022]
Abstract
Monoamine oxidase (MAO) plays a central role in the metabolism of the neurotransmitters dopamine, norepinephrine, and serotonin. This brief review focuses on 3,4-dihydroxyphenylacetaldehyde (DOPAL), which is the immediate product of MAO acting on cytoplasmic dopamine. DOPAL is toxic; however, normally DOPAL is converted via aldehyde dehydrogenase (ALDH) to 3,4-dihydroxyphenylacetic acid (DOPAC), which rapidly exits the neurons. In addition to vesicular uptake of dopamine via the vesicular monoamine transporter (VMAT), the two-enzyme sequence of MAO and ALDH keeps cytoplasmic dopamine levels low. Dopamine oxidizes readily to form toxic products that could threaten neuronal homeostasis. The catecholaldehyde hypothesis posits that diseases featuring catecholaminergic neurodegeneration result from harmful interactions between DOPAL and the protein alpha-synuclein, a major component of Lewy bodies in diseases such as Parkinson disease, dementia with Lewy bodies, and pure autonomic failure. DOPAL potently oligomerizes alpha-synuclein, and alpha-synuclein oligomers impede vesicular functions, shifting the fate of cytoplasmic dopamine toward MAO-catalyzed formation of DOPAL-a vicious cycle. When MAO deaminates dopamine to form DOPAL, hydrogen peroxide is generated; and DOPAL, hydrogen peroxide, and divalent metal cations react to form hydroxyl radicals, which peroxidate lipid membranes. Lipid peroxidation products in turn inhibit ALDH, causing DOPAL to accumulate-another vicious cycle. MAO inhibition decreases DOPAL formation but concurrently increases the spontaneous oxidation of dopamine, potentially trading off one form of toxicity for another. These considerations rationalize a neuroprotection strategy based on concurrent treatment with an MAO inhibitor and an anti-oxidant.
Collapse
Affiliation(s)
- David S Goldstein
- Autonomic Medicine Section, Clinical Neurosciences Program, Division of Intramural Research, National Institute of Neurological, Disorders and Stroke, National Institutes of Health, 9000 Rockville Pike MSC-1620, Building 10 Room 8N260, Bethesda, MD, 20892-1620, USA.
| |
Collapse
|
22
|
Castañeyra-Ruiz L, Castañeyra A, González-Santana A, Machado JD, Borges R. Combining the lack of chromogranins with chronic L-DOPA treatment affects motor activity in mice. Cell Tissue Res 2020; 380:59-66. [PMID: 31900665 DOI: 10.1007/s00441-019-03159-8] [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: 09/09/2019] [Accepted: 12/10/2019] [Indexed: 11/29/2022]
Abstract
We have tested whether the lack of chromogranins (Cgs) A and B could provoke CNS disorders when combined with an excess of dopamine. We chronically treated (over 6 months) mice lacking both chromogranins A and B (Cgs-KO) with a low oral dosage of L-DOPA/benserazide (10/2.5 mg/kg). Motor performance in the rota-rod test, open field activity, and metabolic cages indicated a progressive impairment in motor coordination in these mice, and an increase in rearing behavior, which was accompanied by an increase in DA within the substantia nigra. We conclude that mild chronic L-DOPA treatment does not produce nigro-striatal toxicity that could be associated with parkinsonism, neither in control nor Cgs-KO mice. Rather, Cgs-KO mice exhibit behaviors compatible with an amphetamine-like effect, probably caused by the excess of catecholamines in the CNS.
Collapse
Affiliation(s)
- Leandro Castañeyra-Ruiz
- Department of Neurosurgery, School of Medicine, Washington University in Saint Louis, St. Louis, MO, USA
- Unidad de Farmacología, Facultad de Medicina, Universidad de La Laguna, E-38200, La Laguna, Tenerife, Spain
| | - Agustín Castañeyra
- Dept. Ciencias Médicas Basicas, Facultad de Medicina, Universidad de La Laguna, Tenerife, Spain
| | - Ayoze González-Santana
- Department of Neurosurgery, School of Medicine, Washington University in Saint Louis, St. Louis, MO, USA
- Unidad de Farmacología, Facultad de Medicina, Universidad de La Laguna, E-38200, La Laguna, Tenerife, Spain
- Dept. Ciencias Médicas Basicas, Facultad de Medicina, Universidad de La Laguna, Tenerife, Spain
| | - José D Machado
- Unidad de Farmacología, Facultad de Medicina, Universidad de La Laguna, E-38200, La Laguna, Tenerife, Spain
| | - Ricardo Borges
- Unidad de Farmacología, Facultad de Medicina, Universidad de La Laguna, E-38200, La Laguna, Tenerife, Spain.
| |
Collapse
|
23
|
Zhan Y, Raza MU, Yuan L, Zhu MY. Critical Role of Oxidatively Damaged DNA in Selective Noradrenergic Vulnerability. Neuroscience 2019; 422:184-201. [PMID: 31698021 DOI: 10.1016/j.neuroscience.2019.09.036] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 09/25/2019] [Accepted: 09/27/2019] [Indexed: 12/21/2022]
Abstract
An important pathology in Parkinson's disease (PD) is the earlier and more severe degeneration of noradrenergic neurons in the locus coeruleus (LC) than dopaminergic neurons in the substantia nigra. However, the basis of such selective vulnerability to insults remains obscure. Using noradrenergic and dopaminergic cell lines, as well as primary neuronal cultures from rat LC and ventral mesencephalon (VM), the present study compared oxidative DNA damage response markers after exposure of these cells to hydrogen peroxide (H2O2). The results showed that H2O2 treatment resulted in more severe cell death in noradrenergic cell lines SK-N-BE(2)-M17 and PC12 than dopaminergic MN9D cells. Furthermore, there were higher levels of oxidative DNA damage response markers in noradrenergic cells and primary neuronal cultures from the LC than dopaminergic cells and primary cultures from the VM. It included increased tail moments and tail lengths in Comet assay, and increased protein levels of phosphor-p53 and γ-H2AX after treatments with H2O2. Consistent with these measurements, exposure of SK-N-BE(2)-M17 cells to H2O2 resulted in higher levels of reactive oxygen species (ROS). Further experiments showed that exposure of SK-N-BE(2)-M17 cells to H2O2 caused an increased level of noradrenergic transporter, reduced protein levels of copper transporter (Ctr1) and 8-oxoGua DNA glycosylase, as well as amplified levels of Cav1.2 and Cav1.3 expression. Taken together, these experiments indicated that noradrenergic neuronal cells seem to be more vulnerable to oxidative damage than dopaminergic neurons, which may be related to the intrinsic characteristics of noradrenergic neuronal cells.
Collapse
Affiliation(s)
- Yanqiang Zhan
- Department of Neurology, Remin Hospital of the Wuhan University, Wuhan, China
| | - Muhammad U Raza
- Department of Biomedical Sciences, Quillen College of Medicine, East Tennessee State University, Johnson City, TN, USA
| | - Lian Yuan
- Department of Biomedical Sciences, Quillen College of Medicine, East Tennessee State University, Johnson City, TN, USA
| | - Meng-Yang Zhu
- Department of Biomedical Sciences, Quillen College of Medicine, East Tennessee State University, Johnson City, TN, USA.
| |
Collapse
|
24
|
Abstract
Noradrenergic system of brain supplies the neurotransmitter noradrenalin throughout the brain through widespread efferent projections and play pivotal role in cognitive activities and could be involve in motor and non-motor symptoms of Parkinson's disease (PD) pathology. Profound loss of noradrenergic pathways has been reported in both Parkinson's and Alzheimer's disease (AD) pathology however their employment in therapeutics is still scarce. Therefore the present review is providing the various aspects for involvement on noradrenergic pathways in PD and AD pathology as well as the imaging of locus coeruleus as indicative diagnostic marker for disease. The present review is describing about the role of tiny nucleus locus coeruleus located noradrenergic pathways in said pathologies and discussing the past research as well as lacunas in this regard.
Collapse
Affiliation(s)
- Sarika Singh
- Toxicology and Experimental Medicine Division, CDRI-CSIR, Lucknow, UP, India
| |
Collapse
|
25
|
Sitagliptin and Liraglutide Modulate L-dopa Effect and Attenuate Dyskinetic Movements in Rotenone-Lesioned Rats. Neurotox Res 2019; 35:635-653. [DOI: 10.1007/s12640-019-9998-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 12/15/2018] [Accepted: 01/08/2019] [Indexed: 12/12/2022]
|
26
|
Goldstein DS, Sharabi Y. The heart of PD: Lewy body diseases as neurocardiologic disorders. Brain Res 2019; 1702:74-84. [PMID: 29030055 PMCID: PMC10712237 DOI: 10.1016/j.brainres.2017.09.033] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2017] [Revised: 09/27/2017] [Accepted: 09/28/2017] [Indexed: 01/01/2023]
Abstract
This review provides an update about cardiac sympathetic denervation in Lewy body diseases. The family of Lewy body diseases includes Parkinson's disease (PD), pure autonomic failure (PAF), and dementia with Lewy bodies (DLB). All three feature intra-neuronal cytoplasmic deposits of the protein, alpha-synuclein. Multiple system atrophy (MSA), the parkinsonian form of which can be difficult to distinguish from PD with orthostatic hypotension, involves glial cytoplasmic inclusions that contain alpha-synuclein. By now there is compelling neuroimaging, neuropathologic, and neurochemical evidence for cardiac sympathetic denervation in Lewy body diseases. In addition to denervation, there is decreased storage of catecholamines in the residual terminals. The degeneration develops in a centripetal, retrograde, "dying back" sequence. Across synucleinopathies the putamen and cardiac catecholaminergic lesions seem to occur independently of each other, whereas non-motor aspects of PD (e.g., anosmia, dementia, REM behavior disorder, OH) are associated with each other and with cardiac sympathetic denervation. Cardiac sympathetic denervation can be caused by synucleinopathy in inherited PD. According to the catecholaldehyde hypothesis, 3,4-dihydroxyphenylacetaldehyde (DOPAL), an intermediary metabolite of dopamine, causes or contributes to the death of catecholamine neurons, especially by interacting with proteins such as alpha-synuclein. DOPAL oxidizes spontaneously to DOPAL-quinone, which probably converts alpha-synuclein to its toxic oligomeric form. Decreasing DOPAL production and oxidation might slow the neurodegenerative process. Tracking cardiac sympathetic innervation over time could be the basis for a proof of principle experimental therapeutics trial targeting DOPAL.
Collapse
Affiliation(s)
- David S Goldstein
- Clinical Neurocardiology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892-1620, United States.
| | - Yehonatan Sharabi
- Chaim Sheba Medical Center and Tel Aviv University Sackler Faculty of Medicine, Israel.
| |
Collapse
|
27
|
Lillethorup TP, Glud AN, Alstrup AKO, Noer O, Nielsen EHT, Schacht AC, Landeck N, Kirik D, Orlowski D, Sørensen JCH, Doudet DJ, Landau AM. Longitudinal monoaminergic PET imaging of chronic proteasome inhibition in minipigs. Sci Rep 2018; 8:15715. [PMID: 30356172 PMCID: PMC6200778 DOI: 10.1038/s41598-018-34084-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Accepted: 10/11/2018] [Indexed: 02/08/2023] Open
Abstract
Impairment of the ubiquitin proteasome system has been implicated in Parkinson’s disease. We used positron emission tomography to investigate longitudinal effects of chronic intracerebroventricular exposure to the proteasome inhibitor lactacystin on monoaminergic projections and neuroinflammation. Göttingen minipigs were implanted in the cisterna magna with a catheter connected to a subcutaneous injection port. Minipigs were imaged at baseline and after cumulative doses of 200 and 400 μg lactacystin, respectively. Main radioligands included [11C]-DTBZ (vesicular monoamine transporter type 2) and [11C]-yohimbine (α2-adrenoceptor). [11C]-DASB (serotonin transporter) and [11C]-PK11195 (activated microglia) became available later in the study and we present their results in a smaller subset of animals for information purposes only. Striatal [11C]-DTBZ binding potentials decreased significantly by 16% after 200 μg compared to baseline, but the decrease was not sustained after 400 μg (n = 6). [11C]-yohimbine volume of distribution increased by 18–25% in the pons, grey matter and the thalamus after 200 μg, which persisted at 400 μg (n = 6). In the later subset of minipigs, we observed decreased [11C]-DASB (n = 5) and increased [11C]-PK11195 (n = 3) uptake after 200 μg. These changes may mimic monoaminergic changes and compensatory responses in early Parkinson’s disease.
Collapse
Affiliation(s)
- Thea P Lillethorup
- Department of Nuclear Medicine and PET Center, Department of Clinical Medicine, Aarhus University and Hospital, Aarhus, Denmark
| | - Andreas N Glud
- Center for Experimental Neuroscience (CENSE), Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Aage K O Alstrup
- Department of Nuclear Medicine and PET Center, Department of Clinical Medicine, Aarhus University and Hospital, Aarhus, Denmark
| | - Ove Noer
- Department of Nuclear Medicine and PET Center, Department of Clinical Medicine, Aarhus University and Hospital, Aarhus, Denmark
| | - Erik H T Nielsen
- Department of Nuclear Medicine and PET Center, Department of Clinical Medicine, Aarhus University and Hospital, Aarhus, Denmark
| | - Anna C Schacht
- Department of Nuclear Medicine and PET Center, Department of Clinical Medicine, Aarhus University and Hospital, Aarhus, Denmark
| | - Natalie Landeck
- Brain Repair and Imaging in Neural Systems (BRAINS) Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Deniz Kirik
- Brain Repair and Imaging in Neural Systems (BRAINS) Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Dariusz Orlowski
- Center for Experimental Neuroscience (CENSE), Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Jens Christian H Sørensen
- Center for Experimental Neuroscience (CENSE), Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Doris J Doudet
- Department of Medicine/Neurology, University of British Columbia, Vancouver, BC, Canada
| | - Anne M Landau
- Department of Nuclear Medicine and PET Center, Department of Clinical Medicine, Aarhus University and Hospital, Aarhus, Denmark. .,Translational Neuropsychiatry Unit, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.
| |
Collapse
|
28
|
Hou L, Che Y, Sun F, Wang Q. Taurine protects noradrenergic locus coeruleus neurons in a mouse Parkinson's disease model by inhibiting microglial M1 polarization. Amino Acids 2018; 50:547-556. [PMID: 29508060 DOI: 10.1007/s00726-018-2547-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2017] [Accepted: 02/23/2018] [Indexed: 10/17/2022]
Abstract
Beyond nigrostriatal dopaminergic system, the noradrenergic locus coeruleus (LC/NE) neurons are also degenerated in patients with Parkinson's disease (PD), the second most common neurodegenerative disorder. We previously reported that microglia-mediated neuroinflammation contributes to LC/NE neurodegeneration. The purpose of this study is aimed to test whether taurine, an endogenous amino acid, could be able to protect LC/NE neurons through inhibition of microglial activation using paraquat and maneb-induced mouse PD model. Taurine (150 mg/kg) was administrated (i.p) to mice 30 min prior to paraquat (10 mg/kg) and maneb (30 mg/kg) intoxication for consecutive 6 weeks (twice per week). The results clearly demonstrated that paraquat and maneb co-exposure resulted in loss of tyrosine hydroxylase-positive neurons in the LC in mice, which was significantly ameliorated by taurine. Mechanistically, inhibition of microglia-mediated neuroinflammation contributed to taurine-afforded neuroprotection. Taurine attenuated paraquat and maneb-induced microglial activation and M1 polarization as well as release of proinflammatory cytokines in brainstem of mice. Taurine also abrogated microglial NADPH oxidase activation and oxidative damage in paraquat and maneb-treated mice. Furthermore, inhibition of nuclear factor-κB (NF-κB) but not signal transducers and activators of transcription 1/3 (STAT1/3) signaling pathway participated in taurine-inhibited microglial activation. Collectively, taurine exerted LC/NE neuroprotection against microglia-mediated neurotoxicity. The robust neuroprotective effects of taurine suggest that taurine may be a promising candidate for potential therapy for patients suffering from PD.
Collapse
Affiliation(s)
- Liyan Hou
- School of Public Health, Dalian Medical University, No. 9 W. Lvshun South Road, Dalian, 116044, China
| | - Yuning Che
- School of Public Health, Dalian Medical University, No. 9 W. Lvshun South Road, Dalian, 116044, China
| | - Fuqiang Sun
- School of Public Health, Dalian Medical University, No. 9 W. Lvshun South Road, Dalian, 116044, China
| | - Qingshan Wang
- School of Public Health, Dalian Medical University, No. 9 W. Lvshun South Road, Dalian, 116044, China.
| |
Collapse
|
29
|
Isonaka R, Sullivan P, Jinsmaa Y, Corrales A, Goldstein DS. Spectrum of abnormalities of sympathetic tyrosine hydroxylase and alpha-synuclein in chronic autonomic failure. Clin Auton Res 2018; 28:223-230. [PMID: 29396794 DOI: 10.1007/s10286-017-0495-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Accepted: 12/19/2017] [Indexed: 11/28/2022]
Abstract
OBJECTIVE Lewy body forms of primary chronic autonomic failure (CAF) such as incidental Lewy body disease (ILBD), Parkinson's disease (PD), and pure autonomic failure evolving into dementia with Lewy bodies (PAF+DLB) feature cardiac sympathetic denervation, whereas multiple system atrophy (MSA) in most cases does not. What links Lewy bodies with cardiac sympathetic denervation in CAF? In familial PD, abnormalities of the alpha-synuclein (AS) gene cause CAF and cardiac sympathetic denervation; and in sporadic PD, brainstem Lewy bodies contain AS co-localized with tyrosine hydroxylase (TH), a marker of catecholaminergic neurons. Cytotoxicity from AS deposition within sympathetic neurons might explain noradrenergic denervation in Lewy body forms of CAF. We used immunofluorescence microscopy (IM) to explore this possibility in sympathetic ganglia obtained at autopsy from CAF patients. METHODS Immunoreactive AS and TH were imaged in sympathetic ganglion tissue from 6 control subjects (2 with ILBD), 5 PD patients (1 with concurrent PSP), and 3 patients with CAF (2 PAF + DLB, 1 MSA). RESULTS MSA involved normal ganglionic TH and no AS deposition. In ILBD TH was variably decreased, and TH and AS were co-localized in Lewy bodies. In PD TH was substantially decreased, and TH and AS were co-localized in Lewy bodies. In PAF + DLB TH was virtually absent, but AS was present in Lewy bodies. The PD + PSP patient had AS co-localized with tau but not TH. CONCLUSIONS Sympathetic denervation and intraneuronal AS deposition are correlated across CAF syndromes, consistent with a pathogenic contribution of synucleinopathy to cardiac noradrenergic deficiency in Lewy body diseases.
Collapse
Affiliation(s)
- Risa Isonaka
- Clinical Neurocardiology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, 10 Center Drive MSC-1620, Building 10 Room 8N260, Bethesda, MD, 20892-1620, USA
| | - Patti Sullivan
- Clinical Neurocardiology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, 10 Center Drive MSC-1620, Building 10 Room 8N260, Bethesda, MD, 20892-1620, USA
| | - Yunden Jinsmaa
- Clinical Neurocardiology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, 10 Center Drive MSC-1620, Building 10 Room 8N260, Bethesda, MD, 20892-1620, USA
| | - Abraham Corrales
- Clinical Neurocardiology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, 10 Center Drive MSC-1620, Building 10 Room 8N260, Bethesda, MD, 20892-1620, USA
| | - David S Goldstein
- Clinical Neurocardiology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, 10 Center Drive MSC-1620, Building 10 Room 8N260, Bethesda, MD, 20892-1620, USA.
| |
Collapse
|
30
|
|
31
|
Schildknecht S, Di Monte DA, Pape R, Tieu K, Leist M. Tipping Points and Endogenous Determinants of Nigrostriatal Degeneration by MPTP. Trends Pharmacol Sci 2017; 38:541-555. [DOI: 10.1016/j.tips.2017.03.010] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Revised: 03/23/2017] [Accepted: 03/27/2017] [Indexed: 12/11/2022]
|
32
|
Linking Stress, Catecholamine Autotoxicity, and Allostatic Load with Neurodegenerative Diseases: A Focused Review in Memory of Richard Kvetnansky. Cell Mol Neurobiol 2017; 38:13-24. [PMID: 28488009 DOI: 10.1007/s10571-017-0497-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2017] [Accepted: 04/27/2017] [Indexed: 12/21/2022]
Abstract
In this Focused Review, we provide an update about evolving concepts that may link chronic stress and catecholamine autotoxicity with neurodegenerative diseases such as Parkinson's disease. Richard Kvetnansky's contributions to the field of stress and catecholamine systems inspired some of the ideas presented here. We propose that coordination of catecholaminergic systems mediates adjustments maintaining health and that senescence-related disintegration of these systems leads to disorders of regulation and to neurodegenerative diseases such as Parkinson's disease. Chronically repeated episodes of stress-related catecholamine release and reuptake, with attendant increases in formation of the toxic dopamine metabolite 3,4-dihydroxyphenylacetaldehyde, might accelerate this process.
Collapse
|
33
|
Synaptic vesicle glycoprotein 2C (SV2C) modulates dopamine release and is disrupted in Parkinson disease. Proc Natl Acad Sci U S A 2017; 114:E2253-E2262. [PMID: 28246328 PMCID: PMC5358362 DOI: 10.1073/pnas.1616892114] [Citation(s) in RCA: 84] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Here we describe a role for the synaptic vesicle glycoprotein 2C (SV2C) in dopamine neurotransmission and Parkinson disease (PD). SV2C is expressed on the vesicles of dopamine-producing neurons, and genetic deletion of SV2C causes a reduction in synaptic release of dopamine. The reduced dopamine release is associated with a decrease in motor activity. SV2C is suspected of mediating the neuroprotective effects of nicotine, and we show an ablated neurochemical response to nicotine in SV2C-knockout mice. Last, we demonstrate that SV2C expression is specifically disrupted in mice that express mutated α-synuclein and in humans with PD. Together, these data establish SV2C as an important mediator of dopamine homeostasis and a potential contributor to PD pathogenesis. Members of the synaptic vesicle glycoprotein 2 (SV2) family of proteins are involved in synaptic function throughout the brain. The ubiquitously expressed SV2A has been widely implicated in epilepsy, although SV2C with its restricted basal ganglia distribution is poorly characterized. SV2C is emerging as a potentially relevant protein in Parkinson disease (PD), because it is a genetic modifier of sensitivity to l-DOPA and of nicotine neuroprotection in PD. Here we identify SV2C as a mediator of dopamine homeostasis and report that disrupted expression of SV2C within the basal ganglia is a pathological feature of PD. Genetic deletion of SV2C leads to reduced dopamine release in the dorsal striatum as measured by fast-scan cyclic voltammetry, reduced striatal dopamine content, disrupted α-synuclein expression, deficits in motor function, and alterations in neurochemical effects of nicotine. Furthermore, SV2C expression is dramatically altered in postmortem brain tissue from PD cases but not in Alzheimer disease, progressive supranuclear palsy, or multiple system atrophy. This disruption was paralleled in mice overexpressing mutated α-synuclein. These data establish SV2C as a mediator of dopamine neuron function and suggest that SV2C disruption is a unique feature of PD that likely contributes to dopaminergic dysfunction.
Collapse
|
34
|
Lohr KM, Masoud ST, Salahpour A, Miller GW. Membrane transporters as mediators of synaptic dopamine dynamics: implications for disease. Eur J Neurosci 2017; 45:20-33. [PMID: 27520881 PMCID: PMC5209277 DOI: 10.1111/ejn.13357] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Revised: 07/12/2016] [Accepted: 08/02/2016] [Indexed: 12/14/2022]
Abstract
Dopamine was first identified as a neurotransmitter localized to the midbrain over 50 years ago. The dopamine transporter (DAT; SLC6A3) and the vesicular monoamine transporter 2 (VMAT2; SLC18A2) are regulators of dopamine homeostasis in the presynaptic neuron. DAT transports dopamine from the extracellular space into the cytosol of the presynaptic terminal. VMAT2 then packages this cytosolic dopamine into vesicular compartments for subsequent release upon neurotransmission. Thus, DAT and VMAT2 act in concert to move the transmitter efficiently throughout the neuron. Accumulation of dopamine in the neuronal cytosol can trigger oxidative stress and neurotoxicity, suggesting that the proper compartmentalization of dopamine is critical for neuron function and risk of disease. For decades, studies have examined the effects of reduced transporter function in mice (e.g. DAT-KO, VMAT2-KO, VMAT2-deficient). However, we have only recently been able to assess the effects of elevated transporter expression using BAC transgenic methods (DAT-tg, VMAT2-HI mice). Complemented with in vitro work and neurochemical techniques to assess dopamine compartmentalization, a new focus on the importance of transporter proteins as both models of human disease and potential drug targets has emerged. Here, we review the importance of DAT and VMAT2 function in the delicate balance of neuronal dopamine.
Collapse
Affiliation(s)
- Kelly M Lohr
- Department of Environmental Health, Rollins School of Public Health, Emory University, 1518 Clifton Road, Atlanta, GA, 30322, USA
| | - Shababa T Masoud
- Department of Pharmacology and Toxicology, University of Toronto, ON, Canada
| | - Ali Salahpour
- Department of Pharmacology and Toxicology, University of Toronto, ON, Canada
| | - Gary W Miller
- Department of Environmental Health, Rollins School of Public Health, Emory University, 1518 Clifton Road, Atlanta, GA, 30322, USA
- Center for Neurodegenerative Diseases, Emory University, Atlanta, GA, USA
- Department of Pharmacology, Emory University, Atlanta, GA, USA
- Department of Neurology, Emory University, Atlanta, GA, USA
| |
Collapse
|
35
|
Vermeiren Y, De Deyn PP. Targeting the norepinephrinergic system in Parkinson's disease and related disorders: The locus coeruleus story. Neurochem Int 2017; 102:22-32. [DOI: 10.1016/j.neuint.2016.11.009] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Revised: 11/10/2016] [Accepted: 11/23/2016] [Indexed: 01/12/2023]
|
36
|
Baumann A, Moreira CG, Morawska MM, Masneuf S, Baumann CR, Noain D. Preliminary Evidence of Apathetic-Like Behavior in Aged Vesicular Monoamine Transporter 2 Deficient Mice. Front Hum Neurosci 2016; 10:587. [PMID: 27917116 PMCID: PMC5114272 DOI: 10.3389/fnhum.2016.00587] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 11/03/2016] [Indexed: 12/02/2022] Open
Abstract
Apathy is considered to be a core feature of Parkinson’s disease (PD) and has been associated with a variety of states and symptoms of the disease, such as increased severity of motor symptoms, impaired cognition, executive dysfunction and dementia. Apart from the high prevalence of apathy in PD, which is estimated to be about 40%, the underlying pathophysiology remains poorly understood and current treatment approaches are unspecific and proved to be only partially effective. In animal models, apathy has been sub-optimally modeled, mostly by means of pharmacological and stress-induced methods, whereby concomitant depressive-like symptoms could not be ruled out. In the context of PD only a few studies on toxin-based models (i.e., 6-hydroxydopamine (6-OHDA) or 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)) claimed to have determined apathetic symptoms in animals. The assessment of apathetic symptoms in more elaborated and multifaceted genetic animal models of PD could help to understand the pathophysiological development of apathy in PD and eventually advance specific treatments for afflicted patients. Here we report the presence of behavioral signs of apathy in 12 months old mice that express only ~5% of the vesicular monoamine transporter 2 (VMAT2). Apathetic-like behavior in VMAT2 deficient (LO) mice was evidenced by impaired burrowing and nest building skills, and a reduced preference for sweet solution in the saccharin preference test, while the performance in the forced swimming test was normal. Our preliminary results suggest that VMAT2 deficient mice show an apathetic-like phenotype that might be independent of depressive-like symptoms. Therefore VMAT2 LO mice could be a useful tool to study the pathophysiological substrates of apathy and to test novel treatment strategies for apathy in the context of PD.
Collapse
Affiliation(s)
- Aron Baumann
- Department of Neurology, University Hospital of Zurich Zurich, Switzerland
| | - Carlos G Moreira
- Department of Neurology, University Hospital of Zurich Zurich, Switzerland
| | - Marta M Morawska
- Department of Neurology, University Hospital of Zurich Zurich, Switzerland
| | - Sophie Masneuf
- Department of Neurology, University Hospital of Zurich Zurich, Switzerland
| | | | - Daniela Noain
- Department of Neurology, University Hospital of Zurich Zurich, Switzerland
| |
Collapse
|
37
|
Cliburn RA, Dunn AR, Stout KA, Hoffman CA, Lohr KM, Bernstein AI, Winokur EJ, Burkett J, Schmitz Y, Caudle WM, Miller GW. Immunochemical localization of vesicular monoamine transporter 2 (VMAT2) in mouse brain. J Chem Neuroanat 2016; 83-84:82-90. [PMID: 27836486 DOI: 10.1016/j.jchemneu.2016.11.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Revised: 10/31/2016] [Accepted: 11/04/2016] [Indexed: 12/16/2022]
Abstract
Vesicular monoamine transporter 2 (VMAT2, SLC18A2) is a transmembrane transporter protein that packages dopamine, serotonin, norepinephrine, and histamine into vesicles in preparation for neurotransmitter release from the presynaptic neuron. VMAT2 function and related vesicle dynamics have been linked to susceptibility to oxidative stress, exogenous toxicants, and Parkinson's disease. To address a recent depletion of commonly used antibodies to VMAT2, we generated and characterized a novel rabbit polyclonal antibody generated against a 19 amino acid epitope corresponding to an antigenic sequence within the C-terminal tail of mouse VMAT2. We used genetic models of altered VMAT2 expression to demonstrate that the antibody specifically recognizes VMAT2 and localizes to synaptic vesicles. Furthermore, immunohistochemical labeling using this VMAT2 antibody produces immunoreactivity that is consistent with expected VMAT2 regional distribution. We show the distribution of VMAT2 in monoaminergic brain regions of mouse brain, notably the midbrain, striatum, olfactory tubercle, dopaminergic paraventricular nuclei, tuberomammillary nucleus, raphe nucleus, and locus coeruleus. Normal neurotransmitter vesicle dynamics are critical for proper health and functioning of the nervous system, and this well-characterized VMAT2 antibody will be a useful tool in studying neurodegenerative and neuropsychiatric conditions characterized by vesicular dysfunction.
Collapse
Affiliation(s)
- Rachel A Cliburn
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, United States.
| | - Amy R Dunn
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, United States
| | - Kristen A Stout
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, United States
| | - Carlie A Hoffman
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, United States
| | - Kelly M Lohr
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, United States
| | - Alison I Bernstein
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, United States
| | - Emily J Winokur
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, United States
| | - James Burkett
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, United States
| | - Yvonne Schmitz
- Department of Neurology, Columbia University Medical Center, New York City, NY 10032, United States
| | - William M Caudle
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, United States
| | - Gary W Miller
- Department of Environmental Health, Rollins School of Public Health, Department of Pharmacology, Department of Neurology, Center for Neurodegenerative Diseases, Emory University, Atlanta, GA 30322, United States.
| |
Collapse
|
38
|
Lohr KM, Chen M, Hoffman CA, McDaniel MJ, Stout KA, Dunn AR, Wang M, Bernstein AI, Miller GW. Vesicular Monoamine Transporter 2 (VMAT2) Level Regulates MPTP Vulnerability and Clearance of Excess Dopamine in Mouse Striatal Terminals. Toxicol Sci 2016; 153:79-88. [PMID: 27287315 DOI: 10.1093/toxsci/kfw106] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The vesicular monoamine transporter 2 (VMAT2) packages neurotransmitters for release during neurotransmission and sequesters toxicants into vesicles to prevent neuronal damage. In mice, low VMAT2 levels causes catecholaminergic cell loss and behaviors resembling Parkinson's disease, while high levels of VMAT2 increase dopamine release and protect against dopaminergic toxicants. However, comparisons across these VMAT2 mouse genotypes were impossible due to the differing genetic background strains of the animals. Following back-crossing to a C57BL/6 line, we confirmed that mice with approximately 95% lower VMAT2 levels compared with wild-type (VMAT2-LO) display significantly reduced vesicular uptake, progressive dopaminergic terminal loss with aging, and exacerbated 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) toxicity. Conversely, VMAT2-overexpressing mice (VMAT2-HI) are protected from the loss of striatal terminals following MPTP treatment. We also provide evidence that enhanced vesicular filling in the VMAT2-HI mice modifies the handling of newly synthesized dopamine, indicated by changes in indirect measures of extracellular dopamine clearance. These results confirm the role of VMAT2 in the protection of vulnerable nigrostriatal dopamine neurons and may also provide new insight into the side effects of L-DOPA treatments in Parkinson's disease.
Collapse
Affiliation(s)
- Kelly M Lohr
- *Department of Environmental Health, Rollins School of Public Health
| | - Merry Chen
- *Department of Environmental Health, Rollins School of Public Health
| | - Carlie A Hoffman
- *Department of Environmental Health, Rollins School of Public Health
| | | | - Kristen A Stout
- *Department of Environmental Health, Rollins School of Public Health
| | - Amy R Dunn
- *Department of Environmental Health, Rollins School of Public Health
| | - Minzheng Wang
- *Department of Environmental Health, Rollins School of Public Health
| | | | - Gary W Miller
- *Department of Environmental Health, Rollins School of Public Health Center for Neurodegenerative Diseases Department of Pharmacology Department of Neurology, Emory University, Atlanta, Georgia, 30322
| |
Collapse
|
39
|
Alter SP, Stout KA, Lohr KM, Taylor TN, Shepherd KR, Wang M, Guillot TS, Miller GW. Reduced vesicular monoamine transport disrupts serotonin signaling but does not cause serotonergic degeneration. Exp Neurol 2015; 275 Pt 1:17-24. [PMID: 26428905 DOI: 10.1016/j.expneurol.2015.09.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Revised: 09/11/2015] [Accepted: 09/26/2015] [Indexed: 10/23/2022]
Abstract
We previously demonstrated that mice with reduced expression of the vesicular monoamine transporter 2 (VMAT2 LO) undergo age-related degeneration of the catecholamine-producing neurons of the substantia nigra pars compacta and locus ceruleus and exhibit motor disturbances and depressive-like behavior. In this work, we investigated the effects of reduced vesicular transport on the function and viability of serotonin neurons in these mice. Adult (4-6 months of age), VMAT2 LO mice exhibit dramatically reduced (90%) serotonin release capacity, as measured by fast scan cyclic voltammetry. We observed changes in serotonin receptor responsivity in in vivo pharmacological assays. Aged (months) VMAT2 LO mice exhibited abolished 5-HT1A autoreceptor sensitivity, as determined by 8-OH-DPAT (0.1 mg/kg) induction of hypothermia. When challenged with the 5HT2 agonist, 2,5-dimethoxy-4-iodoamphetamine (1 mg/kg), VMAT2 LO mice exhibited a marked increase (50%) in head twitch responses. We observed sparing of serotonergic terminals in aged mice (18-24 months) throughout the forebrain by SERT immunohistochemistry and [(3)H]-paroxetine binding in striatal homogenates of aged VMAT2 LO mice. In contrast to their loss of catecholamine neurons of the substantia nigra and locus ceruleus, aged VMAT2 LO mice do not exhibit a change in the number of serotonergic (TPH2+) neurons within the dorsal raphe, as measured by unbiased stereology at 26-30 months. Collectively, these data indicate that reduced vesicular monoamine transport significantly disrupts serotonergic signaling, but does not drive degeneration of serotonin neurons.
Collapse
Affiliation(s)
- Shawn P Alter
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA, United States
| | - Kristen A Stout
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA, United States
| | - Kelly M Lohr
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA, United States
| | - Tonya N Taylor
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA, United States
| | - Kennie R Shepherd
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA, United States
| | - Minzheng Wang
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA, United States
| | - Thomas S Guillot
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA, United States
| | - Gary W Miller
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA, United States; Center for Neurodegenerative Disease, School of Medicine, Emory University, Atlanta, GA, United States.
| |
Collapse
|
40
|
Khalife M, Morshedi D, Aliakbari F, Tayaranian Marvian A, Mohammad Beigi H, Azimzadeh Jamalkandi S, Pan-Montojo F. Alpha-Synuclein Fibrils Interact with Dopamine Reducing its Cytotoxicity on PC12 Cells. Protein J 2015; 34:291-303. [DOI: 10.1007/s10930-015-9625-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
41
|
Goldstein DS, Holmes C, Sullivan P, Mash DC, Sidransky E, Stefani A, Kopin IJ, Sharabi Y. Deficient vesicular storage: A common theme in catecholaminergic neurodegeneration. Parkinsonism Relat Disord 2015; 21:1013-22. [PMID: 26255205 DOI: 10.1016/j.parkreldis.2015.07.009] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Revised: 07/06/2015] [Accepted: 07/14/2015] [Indexed: 01/13/2023]
Abstract
Several neurodegenerative diseases involve loss of catecholamine neurons--Parkinson's disease (PD) is a prototypical example. Catecholamine neurons are rare in the nervous system, and why they are lost has been mysterious. Accumulating evidence supports the concept of "autotoxicity"--inherent cytotoxicity caused by catecholamine metabolites. Since vesicular sequestration limits the buildup of toxic products of enzymatic and spontaneous oxidation of catecholamines, a vesicular storage defect could play a pathogenic role in the death of catecholaminergic neurons in a variety of neurodegenerative diseases. In putamen, deficient vesicular storage is revealed in vivo by accelerated loss of (18)F-DOPA-derived radioactivity and post-mortem by decreased tissue dopamine (DA):DOPA ratios; in myocardium in vivo by accelerated loss of (18)F-dopamine-derived radioactivity and post-mortem by increased 3,4-dihydroxyphenylglycol:norepinephrine (DHPG:NE) ratios; and in sympathetic noradrenergic nerves overall in vivo by increased plasma F-dihydroxyphenylacetic acid (F-DOPAC):DHPG ratios. We retrospectively analyzed data from 20 conditions with decreased or intact catecholaminergic innervation, involving different etiologies, pathogenetic mechanisms, and lesion locations. All conditions involving parkinsonism had accelerated loss of putamen (18)F-DOPA-derived radioactivity; in those with post-mortem data there were also decreased putamen DA:DOPA ratios. All conditions involving cardiac sympathetic denervation had accelerated loss of myocardial (18)F-dopamine-derived radioactivity; in those with post-mortem data there were increased myocardial DHPG:NE ratios. All conditions involving localized loss of catecholaminergic innervation had evidence of decreased vesicular storage specifically in the denervated regions. Thus, across neurodegenerative diseases, loss of catecholaminergic neurons seems to be associated with decreased vesicular storage in the residual neurons.
Collapse
Affiliation(s)
- David S Goldstein
- Clinical Neurocardiology Section, Clinical Neurosciences Program, Division of Intramural Research, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, 20892, USA.
| | - Courtney Holmes
- Clinical Neurocardiology Section, Clinical Neurosciences Program, Division of Intramural Research, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Patti Sullivan
- Clinical Neurocardiology Section, Clinical Neurosciences Program, Division of Intramural Research, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Deborah C Mash
- Department of Neurology, Miller School of Medicine, University of Miami, Miami, FL, USA
| | - Ellen Sidransky
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | | | - Irwin J Kopin
- Clinical Neurocardiology Section, Clinical Neurosciences Program, Division of Intramural Research, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Yehonatan Sharabi
- Department of Internal Medicine, Chaim Sheba Medical Center, Tel-HaShomer, and Sackler Faculty of Medicine, Tel-Aviv University School of Medicine, Tel-Avid, Israel
| |
Collapse
|
42
|
Lohr KM, Stout KA, Dunn AR, Wang M, Salahpour A, Guillot TS, Miller GW. Increased Vesicular Monoamine Transporter 2 (VMAT2; Slc18a2) Protects against Methamphetamine Toxicity. ACS Chem Neurosci 2015; 6:790-9. [PMID: 25746685 DOI: 10.1021/acschemneuro.5b00010] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The psychostimulant methamphetamine (METH) is highly addictive and neurotoxic to dopamine terminals. METH toxicity has been suggested to be due to the release and accumulation of dopamine in the cytosol of these terminals. The vesicular monoamine transporter 2 (VMAT2; SLC18A2) is a critical mediator of dopamine handling. Mice overexpressing VMAT2 (VMAT2-HI) have an increased vesicular capacity to store dopamine, thus augmenting striatal dopamine levels and dopamine release in the striatum. Based on the altered compartmentalization of intracellular dopamine in the VMAT2-HI mice, we assessed whether enhanced vesicular function was capable of reducing METH-induced damage to the striatal dopamine system. While wildtype mice show significant losses in striatal levels of the dopamine transporter (65% loss) and tyrosine hydroxylase (46% loss) following a 4 × 10 mg/kg METH dosing regimen, VMAT2-HI mice were protected from this damage. VMAT2-HI mice were also spared from the inflammatory response that follows METH treatment, showing an increase in astroglial markers that was approximately one-third of that of wildtype animals (117% vs 36% increase in GFAP, wildtype vs VMAT2-HI). Further analysis also showed that elevated VMAT2 level does not alter the ability of METH to increase core body temperature, a mechanism integral to the toxicity of the drug. Finally, the VMAT2-HI mice showed no difference from wildtype littermates on both METH-induced conditioned place preference and in METH-induced locomotor activity (1 mg/kg METH). These results demonstrate that elevated VMAT2 protects against METH toxicity without enhancing the rewarding effects of the drug. Since the VMAT2-HI mice are protected from METH despite higher basal dopamine levels, this study suggests that METH toxicity depends more on the proper compartmentalization of synaptic dopamine than on the absolute amount of dopamine in the brain.
Collapse
Affiliation(s)
| | | | | | | | - Ali Salahpour
- Department
of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | | | | |
Collapse
|
43
|
Goldstein DS, Sullivan P, Cooney A, Jinsmaa Y, Kopin IJ, Sharabi Y. Rotenone decreases intracellular aldehyde dehydrogenase activity: implications for the pathogenesis of Parkinson's disease. J Neurochem 2015; 133:14-25. [PMID: 25645689 DOI: 10.1111/jnc.13042] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Revised: 01/08/2015] [Accepted: 01/12/2015] [Indexed: 12/20/2022]
Abstract
Repeated systemic administration of the mitochondrial complex I inhibitor rotenone produces a rodent model of Parkinson's disease (PD). Mechanisms of relatively selective rotenone-induced damage to nigrostriatal dopaminergic neurons remain incompletely understood. According to the 'catecholaldehyde hypothesis,' buildup of the autotoxic dopamine metabolite 3,4-dihydroxyphenylacetaldehyde (DOPAL) contributes to PD pathogenesis. Vesicular uptake blockade increases DOPAL levels, and DOPAL is detoxified mainly by aldehyde dehydrogenase (ALDH). We tested whether rotenone interferes with vesicular uptake and intracellular ALDH activity. Endogenous and F-labeled catechols were measured in PC12 cells incubated with rotenone (0-1000 nM, 180 min), without or with F-dopamine (2 μM) to track vesicular uptake and catecholamine metabolism. Rotenone dose dependently increased DOPAL, F-DOPAL, and 3,4-dihydroxyphenylethanol (DOPET) levels while decreasing dopamine and 3,4-dihydroxyphenylacetic acid (DOPAC) levels and the ratio of dopamine to the sum of its deaminated metabolites. In test tubes, rotenone did not affect conversion of DOPAL to DOPAC by ALDH when NAD(+) was supplied, whereas the direct-acting ALDH inhibitor benomyl markedly increased DOPAL and decreased DOPAC concentrations in the reaction mixtures. We propose that rotenone builds up intracellular DOPAL by decreasing ALDH activity and attenuating vesicular sequestration of cytoplasmic catecholamines. The results provide a novel mechanism for selective rotenone-induced toxicity in dopaminergic neurons. We report that rotenone, a mitochondrial complex I inhibitor that produces an animal model of Parkinson's disease, increases intracellular levels of the toxic dopamine metabolite 3,4-dihydroxyphenyl-acetaldehyde (DOPAL), via decreased DOPAL metabolism by aldehyde dehydrogenase (ALDH) and decreased vesicular sequestration of cytoplasmic dopamine by the vesicular monoamine transporter (VMAT). The results provide a novel mechanism for rotenone-induced toxicity in dopaminergic neurons.
Collapse
Affiliation(s)
- David S Goldstein
- Clinical Neurocardiology Section, CNP/DIR/NINDS/NIH, Bethesda, Maryland, USA
| | | | | | | | | | | |
Collapse
|
44
|
Jinsmaa Y, Cooney A, Sullivan P, Sharabi Y, Goldstein DS. The serotonin aldehyde, 5-HIAL, oligomerizes alpha-synuclein. Neurosci Lett 2015; 590:134-7. [PMID: 25637699 DOI: 10.1016/j.neulet.2015.01.064] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Revised: 01/22/2015] [Accepted: 01/26/2015] [Indexed: 11/16/2022]
Abstract
In Parkinson's disease (PD) alpha-synuclein oligomers are thought to be pathogenic, and 3,4-dihydroxyphenylacetaldehyde (DOPAL), an obligate aldehyde intermediate in neuronal dopamine metabolism, potently oligomerizes alpha-synuclein. PD involves alpha-synuclein deposition in brainstem raphe nuclei; however, whether 5-hydroxyindoleacetaldehyde (5-HIAL), the aldehyde of serotonin, oligomerizes alpha-synuclein has been unknown. In this study we tested whether 5-HIAL oligomerizes alpha-synuclein in vitro and in PC12 cells conditionally over-expressing alpha-synuclein. Alpha-synuclein oligomers were quantified by western blotting after incubation of alpha-synuclein with serotonin and monoamine oxidase-A (MAO-A) to generate 5-HIAL or dopamine to generate DOPAL. Oligomerization of alpha-synuclein in PC12 cells over-expressing the protein was compared between vehicle-treated cells and cells incubated with levodopa to generate DOPAL or 5-hydroxytryptophan to generate 5-HIAL. Monoamine aldehyde mediation of the oligomerization was assessed using the MAO inhibitor, pargyline. Dopamine and serotonin incubated with MAO-A both strongly oligomerized alpha-synuclein (more than 10 times control); pargyline blocked the oligomerization. In synuclein overexpressing PC12 cells, levodopa and 5-hydroxytryptophan elicited pargyline-sensitive alpha-synuclein oligomerization. 5-HIAL oligomerizes alpha-synuclein both in vitro and in synuclein-overexpressing PC12 cells, in a manner similar to DOPAL. The findings may help explain loss of serotonergic neurons in PD.
Collapse
Affiliation(s)
- Yunden Jinsmaa
- Clinical Neurocardiology Section, Clinical Neurosciences Program, Division of Intramural Research, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892 USA
| | - Adele Cooney
- Clinical Neurocardiology Section, Clinical Neurosciences Program, Division of Intramural Research, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892 USA
| | - Patricia Sullivan
- Clinical Neurocardiology Section, Clinical Neurosciences Program, Division of Intramural Research, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892 USA
| | - Yehonatan Sharabi
- Department of Internal Medicine, Chaim Sheba Medical Center, Tel-HaShomer, Israel
| | - David S Goldstein
- Clinical Neurocardiology Section, Clinical Neurosciences Program, Division of Intramural Research, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892 USA.
| |
Collapse
|
45
|
Blesa J, Przedborski S. Parkinson's disease: animal models and dopaminergic cell vulnerability. Front Neuroanat 2014; 8:155. [PMID: 25565980 PMCID: PMC4266040 DOI: 10.3389/fnana.2014.00155] [Citation(s) in RCA: 341] [Impact Index Per Article: 34.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Accepted: 11/27/2014] [Indexed: 12/18/2022] Open
Abstract
Parkinson's disease (PD) is a neurodegenerative disorder that affects about 1.5% of the global population over 65 years of age. A hallmark feature of PD is the degeneration of the dopamine (DA) neurons in the substantia nigra pars compacta (SNc) and the consequent striatal DA deficiency. Yet, the pathogenesis of PD remains unclear. Despite tremendous growth in recent years in our knowledge of the molecular basis of PD and the molecular pathways of cell death, important questions remain, such as: (1) why are SNc cells especially vulnerable; (2) which mechanisms underlie progressive SNc cell loss; and (3) what do Lewy bodies or α-synuclein reveal about disease progression. Understanding the variable vulnerability of the dopaminergic neurons from the midbrain and the mechanisms whereby pathology becomes widespread are some of the primary objectives of research in PD. Animal models are the best tools to study the pathogenesis of PD. The identification of PD-related genes has led to the development of genetic PD models as an alternative to the classical toxin-based ones, but does the dopaminergic neuronal loss in actual animal models adequately recapitulate that of the human disease? The selection of a particular animal model is very important for the specific goals of the different experiments. In this review, we provide a summary of our current knowledge about the different in vivo models of PD that are used in relation to the vulnerability of the dopaminergic neurons in the midbrain in the pathogenesis of PD.
Collapse
Affiliation(s)
- Javier Blesa
- Department of Pathology and Cell Biology, Center for Motor Neuron Biology and Disease, College of Physicians and Surgeons, Columbia UniversityNew York, NY, USA
| | | |
Collapse
|
46
|
Goldstein DS, Kopin IJ, Sharabi Y. Catecholamine autotoxicity. Implications for pharmacology and therapeutics of Parkinson disease and related disorders. Pharmacol Ther 2014; 144:268-82. [PMID: 24945828 PMCID: PMC4591072 DOI: 10.1016/j.pharmthera.2014.06.006] [Citation(s) in RCA: 116] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Accepted: 05/29/2014] [Indexed: 02/07/2023]
Abstract
Several neurodegenerative diseases involve loss of catecholamine neurons-Parkinson disease is a prototypical example. Catecholamine neurons are rare in the nervous system, and why they are vulnerable in PD and related disorders has been mysterious. Accumulating evidence supports the concept of "autotoxicity"-inherent cytotoxicity of catecholamines and their metabolites in the cells in which they are produced. According to the "catecholaldehyde hypothesis" for the pathogenesis of Parkinson disease, long-term increased build-up of 3,4-dihydroxyphenylacetaldehyde (DOPAL), the catecholaldehyde metabolite of dopamine, causes or contributes to the eventual death of dopaminergic neurons. Lewy bodies, a neuropathologic hallmark of PD, contain precipitated alpha-synuclein. Bases for the tendency of alpha-synuclein to precipitate in the cytoplasm of catecholaminergic neurons have also been mysterious. Since DOPAL potently oligomerizes and aggregates alpha-synuclein, the catecholaldehyde hypothesis provides a link between alpha-synucleinopathy and catecholamine neuron loss in Lewy body diseases. The concept developed here is that DOPAL and alpha-synuclein are nodes in a complex nexus of interacting homeostatic systems. Dysfunctions of several processes, including decreased vesicular sequestration of cytoplasmic catecholamines, decreased aldehyde dehydrogenase activity, and oligomerization of alpha-synuclein, lead to conversion from the stability afforded by negative feedback regulation to the instability, degeneration, and system failure caused by induction of positive feedback loops. These dysfunctions result from diverse combinations of genetic predispositions, environmental exposures, stress, and time. The notion of catecholamine autotoxicity has several implications for treatment, disease modification, and prevention. Conversely, disease modification clinical trials would provide key tests of the catecholaldehyde hypothesis.
Collapse
Affiliation(s)
- David S Goldstein
- Clinical Neurocardiology Section, Clinical Neurosciences Program, Division of Intramural Research, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA.
| | - Irwin J Kopin
- Clinical Neurocardiology Section, Clinical Neurosciences Program, Division of Intramural Research, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | | |
Collapse
|
47
|
Lizarraga LE, Cholanians AB, Phan AV, Herndon JM, Lau SS, Monks TJ. Vesicular monoamine transporter 2 and the acute and long-term response to 3,4-(±)-methylenedioxymethamphetamine. Toxicol Sci 2014; 143:209-19. [PMID: 25370842 DOI: 10.1093/toxsci/kfu222] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
3,4-(±)-Methylenedioxymethamphetamine (MDMA, Ecstasy) is a ring-substituted amphetamine derivative with potent psychostimulant properties. The neuropharmacological effects of MDMA are biphasic in nature, initially causing synaptic monoamine release, primarily of serotonin (5-HT). Conversely, the long-term effects of MDMA manifest as prolonged depletions in 5-HT, and reductions in 5-HT reuptake transporter (SERT), indicative of serotonergic neurotoxicity. MDMA-induced 5-HT efflux relies upon disruption of vesicular monoamine storage, which increases cytosolic 5-HT concentrations available for release via a carrier-mediated mechanism. The vesicular monoamine transporter 2 (VMAT2) is responsible for packaging monoamine neurotransmitters into cytosolic vesicles. Thus, VMAT2 is a molecular target for a number of psychostimulant drugs, including methamphetamine and MDMA. We investigated the effects of depressed VMAT2 activity on the adverse responses to MDMA, via reversible inhibition of the VMAT2 protein with Ro4-1284. A single dose of MDMA (20 mg/kg, subcutaneous) induced significant hyperthermia in rats. Ro4-1284 (10 mg/kg, intraperitoneal) pretreatment prevented the thermogenic effects of MDMA, instead causing a transient decrease in body temperature. MDMA-treated rats exhibited marked increases in horizontal velocity and rearing behavior. In the presence of Ro4-1284, MDMA-mediated horizontal hyperlocomotion was delayed and attenuated, whereas rearing activity was abolished. Finally, Ro4-1284 prevented deficits in 5-HT content in rat cortex and striatum, and reduced depletions in striatal SERT staining, 7 days after MDMA administration. In summary, acute inhibition of VMAT2 by Ro4-1284 protected against MDMA-mediated hyperthermia, hyperactivity, and serotonergic neurotoxicity. The data suggest the involvement of VMAT2 in the thermoregulatory, behavioral, and neurotoxic effects of MDMA.
Collapse
Affiliation(s)
- Lucina E Lizarraga
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Arizona, Tucson, Arizona 85721
| | - Aram B Cholanians
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Arizona, Tucson, Arizona 85721
| | - Andy V Phan
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Arizona, Tucson, Arizona 85721
| | - Joseph M Herndon
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Arizona, Tucson, Arizona 85721
| | - Serrine S Lau
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Arizona, Tucson, Arizona 85721
| | - Terrence J Monks
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Arizona, Tucson, Arizona 85721
| |
Collapse
|
48
|
Salvatore MF, Disbrow EA, Emborg ME. Peripheral and cognitive signs: delineating the significance of impaired catecholamine metabolism in Parkinson's disease progression. J Neurochem 2014; 131:129-33. [PMID: 25039428 DOI: 10.1111/jnc.12796] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Accepted: 06/18/2014] [Indexed: 01/07/2023]
Affiliation(s)
- Michael F Salvatore
- Department of Pharmacology, Toxicology & Neuroscience, Louisiana State University Health Sciences Center, Shreveport, Louisiana, USA
| | - Elizabeth A Disbrow
- Department of Pharmacology, Toxicology & Neuroscience, Louisiana State University Health Sciences Center, Shreveport, Louisiana, USA.,Department of Neurology, Louisiana State University Health Sciences Center, Shreveport, Louisiana, USA
| | - Marina E Emborg
- Wisconsin National Primate Research Center and Department of Medical Physics, University of Wisconsin, Madison, Wisconsin, USA
| |
Collapse
|
49
|
Increased vesicular monoamine transporter enhances dopamine release and opposes Parkinson disease-related neurodegeneration in vivo. Proc Natl Acad Sci U S A 2014; 111:9977-82. [PMID: 24979780 DOI: 10.1073/pnas.1402134111] [Citation(s) in RCA: 139] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Disruption of neurotransmitter vesicle dynamics (transport, capacity, release) has been implicated in a variety of neurodegenerative and neuropsychiatric conditions. Here, we report a novel mouse model of enhanced vesicular function via bacterial artificial chromosome (BAC)-mediated overexpression of the vesicular monoamine transporter 2 (VMAT2; Slc18a2). A twofold increase in vesicular transport enhances the vesicular capacity for dopamine (56%), dopamine vesicle volume (33%), and basal tissue dopamine levels (21%) in the mouse striatum. The elevated vesicular capacity leads to an increase in stimulated dopamine release (84%) and extracellular dopamine levels (44%). VMAT2-overexpressing mice show improved outcomes on anxiety and depressive-like behaviors and increased basal locomotor activity (41%). Finally, these mice exhibit significant protection from neurotoxic insult by the dopaminergic toxicant 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), as measured by reduced dopamine terminal damage and substantia nigra pars compacta cell loss. The increased release of dopamine and neuroprotection from MPTP toxicity in the VMAT2-overexpressing mice suggest that interventions aimed at enhancing vesicular capacity may be of therapeutic benefit in Parkinson disease.
Collapse
|
50
|
Goldstein DS, Sullivan P, Holmes C, Miller GW, Sharabi Y, Kopin IJ. A vesicular sequestration to oxidative deamination shift in myocardial sympathetic nerves in Parkinson's disease. J Neurochem 2014; 131:219-28. [PMID: 24848581 DOI: 10.1111/jnc.12766] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 05/12/2014] [Accepted: 05/15/2014] [Indexed: 01/17/2023]
Abstract
In Parkinson's disease (PD), profound putamen dopamine (DA) depletion reflects denervation and a shift from vesicular sequestration to oxidative deamination of cytoplasmic DA in residual terminals. PD also involves cardiac sympathetic denervation. Whether PD entails myocardial norepinephrine (NE) depletion and a sequestration-deamination shift have been unknown. We measured apical myocardial tissue concentrations of NE, DA, and their neuronal metabolites 3,4-dihydroxyphenylglycol (DHPG), and 3,4-dihydroxyphenylacetic acid (DOPAC) from 23 PD patients and 23 controls and ascertained the extent of myocardial NE depletion in PD. We devised, validated in VMAT2-Lo mice, and applied 5 neurochemical indices of the sequestration-deamination shift-concentration ratios of DOPAC:DA, DA:NE, DHPG:NE, DOPAC:NE, and DHPG:DOPAC-and used a kinetic model to estimate the extent of the vesicular storage defect. The PD group had decreased myocardial NE content (p < 0.0001). The majority of patients (70%) had severe NE depletion (mean 2% of control), and in this subgroup all five indices of a sequestration-deamination shift were increased compared to controls (p < 0.001 for each). Vesicular storage in residual nerves was estimated to be decreased by 84-91% in this subgroup. We conclude that most PD patients have severe myocardial NE depletion, because of both sympathetic denervation and decreased vesicular storage in residual nerves. We found that the majority (70%) of Parkinson's disease (PD) patients have profound (98%) myocardial norepinephrine depletion, because of both cardiac sympathetic denervation and a shift from vesicular sequestration to oxidative deamination of cytoplasmic catecholamines in the residual nerves. This shift may be part of a final common pathogenetic pathway in the loss of catecholaminergic neurons that characterizes PD.
Collapse
Affiliation(s)
- David S Goldstein
- Clinical Neurocardiology Section, CNP/DIR/NINDS/NIH, Bethesda, Maryland, USA
| | - Patricia Sullivan
- Clinical Neurocardiology Section, CNP/DIR/NINDS/NIH, Bethesda, Maryland, USA
| | - Courtney Holmes
- Clinical Neurocardiology Section, CNP/DIR/NINDS/NIH, Bethesda, Maryland, USA
| | - Gary W Miller
- School of Public Health, Environmental Health, Emory University, Atlanta, Georgia, USA
| | - Yehonatan Sharabi
- Hypertension Unit, Chaim Sheba Medical Center, and Tel Aviv University, Tel-HaShomer, Israel
| | - Irwin J Kopin
- Clinical Neurocardiology Section, CNP/DIR/NINDS/NIH, Bethesda, Maryland, USA
| |
Collapse
|