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Arnts H, Coolen SE, Fernandes FW, Schuurman R, Krauss JK, Groenewegen HJ, van den Munckhof P. The intralaminar thalamus: a review of its role as a target in functional neurosurgery. Brain Commun 2023; 5:fcad003. [PMID: 37292456 PMCID: PMC10244065 DOI: 10.1093/braincomms/fcad003] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 10/06/2022] [Accepted: 01/03/2023] [Indexed: 09/29/2023] Open
Abstract
The intralaminar thalamus, in particular the centromedian-parafascicular complex, forms a strategic node between ascending information from the spinal cord and brainstem and forebrain circuitry that involves the cerebral cortex and basal ganglia. A large body of evidence shows that this functionally heterogeneous region regulates information transmission in different cortical circuits, and is involved in a variety of functions, including cognition, arousal, consciousness and processing of pain signals. Not surprisingly, the intralaminar thalamus has been a target area for (radio)surgical ablation and deep brain stimulation (DBS) in different neurological and psychiatric disorders. Historically, ablation and stimulation of the intralaminar thalamus have been explored in patients with pain, epilepsy and Tourette syndrome. Moreover, DBS has been used as an experimental treatment for disorders of consciousness and a variety of movement disorders. In this review, we provide a comprehensive analysis of the underlying mechanisms of stimulation and ablation of the intralaminar nuclei, historical clinical evidence, and more recent (experimental) studies in animals and humans to define the present and future role of the intralaminar thalamus as a target in the treatment of neurological and psychiatric disorders.
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Affiliation(s)
- Hisse Arnts
- Department of Neurosurgery, Amsterdam University Medical Centers, location Academic Medical Center, Amsterdam, The Netherlands
- Department of Neurosurgery, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Stan E Coolen
- Department of Neurosurgery, Amsterdam University Medical Centers, location Academic Medical Center, Amsterdam, The Netherlands
| | | | - Rick Schuurman
- Department of Neurosurgery, Amsterdam University Medical Centers, location Academic Medical Center, Amsterdam, The Netherlands
| | - Joachim K Krauss
- Department of Neurosurgery, Hannover Medical School, Hannover, Germany
| | - Henk J Groenewegen
- Department of Anatomy and Neurosciences, Neuroscience Campus Amsterdam, Amsterdam University Medical Centers, location VU University Medical Center, Amsterdam, The Netherlands
| | - Pepijn van den Munckhof
- Department of Neurosurgery, Amsterdam University Medical Centers, location Academic Medical Center, Amsterdam, The Netherlands
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Martel AC, Galvan A. Connectivity of the corticostriatal and thalamostriatal systems in normal and parkinsonian states: An update. Neurobiol Dis 2022; 174:105878. [PMID: 36183947 PMCID: PMC9976706 DOI: 10.1016/j.nbd.2022.105878] [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: 07/02/2022] [Revised: 09/23/2022] [Accepted: 09/28/2022] [Indexed: 02/06/2023] Open
Abstract
The striatum receives abundant glutamatergic afferents from the cortex and thalamus. These inputs play a major role in the functions of the striatal neurons in normal conditions, and are significantly altered in pathological states, such as Parkinson's disease. This review summarizes the current knowledge of the connectivity of the corticostriatal and thalamostriatal pathways, with emphasis on the most recent advances in the field. We also discuss novel findings regarding structural changes in cortico- and thalamostriatal connections that occur in these connections as a consequence of striatal loss of dopamine in parkinsonism.
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Affiliation(s)
- Anne-Caroline Martel
- Emory National Primate Research Center, Emory University, Atlanta, GA, USA; Udall Center of Excellence for Parkinson's Disease Research, Emory University, Atlanta, GA, USA
| | - Adriana Galvan
- Emory National Primate Research Center, Emory University, Atlanta, GA, USA; Udall Center of Excellence for Parkinson's Disease Research, Emory University, Atlanta, GA, USA; Department of Neurology, School of Medicine, Emory University, Atlanta, GA, USA.
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Tanimura A, Shen W, Wokosin D, Surmeier DJ. Pathway-Specific Remodeling of Thalamostriatal Synapses in a Mouse Model of Parkinson's Disease. Mov Disord 2022; 37:1164-1174. [PMID: 35485341 PMCID: PMC9232945 DOI: 10.1002/mds.29030] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Accepted: 03/21/2022] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND The network pathophysiology underlying the motor symptoms of Parkinson's disease (PD) is poorly understood. In models of late-stage PD, there is significant cell-specific remodeling of corticostriatal, axospinous glutamatergic synapses on principal spiny projection neurons (SPNs). Neurons in the centrolateral nucleus (CLN) of the thalamus that relay cerebellar activity to the striatum also make axospinous synapses on SPNs, but the extent to which they are affected in PD has not been definitively characterized. OBJECTIVE To fill this gap, transgenic mice in which CLN neurons express Cre recombinase were used in conjunction with optogenetic and circuit mapping approaches to determine changes in the CLN projection to SPNs in a unilateral 6-hydroxydopamine (6-OHDA) model of late-stage PD. METHODS Adeno-associated virus vectors carrying Cre-dependent opsin expression constructs were stereotaxically injected into the CLN of Grp-KH288 mice in which CLN, but not parafascicular nucleus neurons, expressed Cre recombinase. The properties of this projection to identify direct pathway spiny projection neurons (dSPNs) and indirect pathway spiny projection neurons (iSPNs) were then studied in ex vivo brain slices of the dorsolateral striatum from control and 6-OHDA lesioned mice using anatomic, optogenetic, and electrophysiological approaches. RESULTS Optogenetically evoked excitatory synaptic currents in both iSPNs and dSPNs were reduced in lesioned mice; however, the reduction was significantly greater in dSPNs. In iSPNs, the reduction in evoked responses was attributable to synaptic pruning, because synaptic channelrhodopsin assisted circuit mapping (sCRACm) revealed fewer synapses per cell after lesioning. In contrast, sCRACm mapping of CLN inputs to dSPNs failed to detect any change in synapse abundance in lesioned mice. However, the ratio of currents through α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors to those through N-methyl-D-aspartate receptors was significantly reduced in dSPNs. Moreover, the distribution of currents evoked by optical stimulation of individual synapses shifted toward smaller amplitudes by lesioning, suggesting that they had undergone long-term depression. CONCLUSIONS Taken together, our results demonstrate that the CLN projection to the striatum undergoes a pathway-specific remodeling that could contribute to the circuit imbalance thought to drive the hypokinetic features of PD. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Asami Tanimura
- Department of Neuroscience, Feinberg School of MedicineNorthwestern UniversityChicagoIllinoisUSA
- Department of BiomedicineAarhus UniversityAarhusDenmark
| | - Weixing Shen
- Department of Neuroscience, Feinberg School of MedicineNorthwestern UniversityChicagoIllinoisUSA
| | - David Wokosin
- Department of Neuroscience, Feinberg School of MedicineNorthwestern UniversityChicagoIllinoisUSA
| | - D. James Surmeier
- Department of Neuroscience, Feinberg School of MedicineNorthwestern UniversityChicagoIllinoisUSA
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4
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Striatal synaptic adaptations in Parkinson's disease. Neurobiol Dis 2022; 167:105686. [PMID: 35272023 DOI: 10.1016/j.nbd.2022.105686] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 02/16/2022] [Accepted: 03/03/2022] [Indexed: 01/02/2023] Open
Abstract
The striatum is densely innervated by mesencephalic dopaminergic neurons that modulate acquisition and vigor of goal-directed actions and habits. This innervation is progressively lost in Parkinson's disease (PD), contributing to the defining movement deficits of the disease. Although boosting dopaminergic signaling with levodopa early in the course of the disease alleviates these deficits, later this strategy leads to the emergence of debilitating dyskinesia. Here, recent advances in our understanding of how striatal cells and circuits adapt to this progressive de-innervation and to levodopa therapy are discussed. First, we discuss how dopamine (DA) depletion triggers cell type-specific, homeostatic changes in spiny projection neurons (SPNs) that tend to normalize striatal activity but also lead to disruption of the synaptic architecture sculpted by experience. Second, we discuss the roles played by cholinergic and nitric oxide-releasing interneurons in these adaptations. Third, we examine recent work in freely moving mice suggesting that alterations in the spatiotemporal dynamics of striatal ensembles contributes to PD movement deficits. Lastly, we discuss recently published evidence from a progressive model of PD suggesting that contrary to the classical model, striatal pathway imbalance is necessary but not sufficient to produce frank parkinsonism.
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Ayers-Ringler J, McDonald JS, Connors MA, Fisher CR, Han S, Jakaitis DR, Scherer B, Tutor G, Wininger KM, Dai D, Choi DS, Salisbury JL, Jannetto PJ, Bornhorst JA, Kadirvel R, Kallmes DF, McDonald RJ. Neurologic Effects of Gadolinium Retention in the Brain after Gadolinium-based Contrast Agent Administration. Radiology 2021; 302:676-683. [PMID: 34931861 PMCID: PMC8893178 DOI: 10.1148/radiol.210559] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Background Concerns over the neurotoxic potential of retained gadolinium in brain tissues after intravenous gadolinium-based contrast agent (GBCA) administration have led to pronounced worldwide use changes, yet the clinical sequelae of gadolinium retention remain undefined. Purpose To assess clinical and neurologic effects and potential neurotoxicity of gadolinium retention in rats after administration of various GBCAs. Materials and Methods From March 2017 through July 2018, 183 male Wistar rats received 20 intravenous injections of 2.5 mmol per kilogram of body weight (80 human equivalent doses) of various GBCAs (gadodiamide, gadobenate, gadopentetate, gadoxetate, gadobutrol, gadoterate, and gadoteridol) or saline over 4 weeks. Rats were evaluated 6 and 34 weeks after injection with five behavioral tests, and inductively coupled plasma mass spectrometry, transmission electron microscopy, and histopathology were performed on urine, serum, cerebrospinal fluid (CSF), basal ganglia, dentate nucleus, and kidney samples. Dunnett post hoc test and Wilcoxon rank sum test were used to compare differences between treatment groups. Results No evidence of differences in any behavioral test was observed between GBCA-exposed rats and control animals at either 6 or 34 weeks (P = .08 to P = .99). Gadolinium concentrations in both neuroanatomic locations were higher in linear GBCA-exposed rats than macrocyclic GBCA-exposed rats at 6 and 34 weeks (P < .001). Gadolinium clearance over time varied among GBCAs, with gadobutrol having the largest clearance (median: 62% for basal ganglia, 70% for dentate) and gadodiamide having no substantial clearance. At 34 weeks, gadolinium was largely cleared from the CSF and serum of gadodiamide-, gadobenate-, gadoterate-, and gadobutrol-exposed rats, especially for the macrocyclic agents (range: 70%-98% removal for CSF, 34%-94% removal for serum), and was nearly completely removed from urine (range: 96%-99% removal). Transmission electron microscopy was used to detect gadolinium foci in linear GBCA-exposed brain tissue, but no histopathologic differences were observed for any GBCA. Conclusion In this rat model, no clinical evidence of neurotoxicity was observed after exposure to linear and macrocyclic gadolinium-based contrast agents at supradiagnostic doses. © RSNA, 2022 Online supplemental material is available for this article.
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Affiliation(s)
- Jennifer Ayers-Ringler
- From the Departments of Radiology (J.A., J.S.M., M.A.C., C.R.F., S.H., D.R.J., B.S., G.T., D.D., R.K., D.F.K., R.J.M.), Molecular Pharmacology and Experimental Therapeutics (K.M.W., D.S.C.), Biochemistry and Molecular Biology (J.L.S.), Laboratory Medicine and Pathology (P.J.J., J.A.B.), and Neurosurgery, College of Medicine (D.F.K.), Mayo Clinic, 200 1st St SW, Rochester, MN 55905
| | - Jennifer S. McDonald
- From the Departments of Radiology (J.A., J.S.M., M.A.C., C.R.F., S.H., D.R.J., B.S., G.T., D.D., R.K., D.F.K., R.J.M.), Molecular Pharmacology and Experimental Therapeutics (K.M.W., D.S.C.), Biochemistry and Molecular Biology (J.L.S.), Laboratory Medicine and Pathology (P.J.J., J.A.B.), and Neurosurgery, College of Medicine (D.F.K.), Mayo Clinic, 200 1st St SW, Rochester, MN 55905
| | - Margaret A. Connors
- From the Departments of Radiology (J.A., J.S.M., M.A.C., C.R.F., S.H., D.R.J., B.S., G.T., D.D., R.K., D.F.K., R.J.M.), Molecular Pharmacology and Experimental Therapeutics (K.M.W., D.S.C.), Biochemistry and Molecular Biology (J.L.S.), Laboratory Medicine and Pathology (P.J.J., J.A.B.), and Neurosurgery, College of Medicine (D.F.K.), Mayo Clinic, 200 1st St SW, Rochester, MN 55905
| | - Cody R. Fisher
- From the Departments of Radiology (J.A., J.S.M., M.A.C., C.R.F., S.H., D.R.J., B.S., G.T., D.D., R.K., D.F.K., R.J.M.), Molecular Pharmacology and Experimental Therapeutics (K.M.W., D.S.C.), Biochemistry and Molecular Biology (J.L.S.), Laboratory Medicine and Pathology (P.J.J., J.A.B.), and Neurosurgery, College of Medicine (D.F.K.), Mayo Clinic, 200 1st St SW, Rochester, MN 55905
| | - Susie Han
- From the Departments of Radiology (J.A., J.S.M., M.A.C., C.R.F., S.H., D.R.J., B.S., G.T., D.D., R.K., D.F.K., R.J.M.), Molecular Pharmacology and Experimental Therapeutics (K.M.W., D.S.C.), Biochemistry and Molecular Biology (J.L.S.), Laboratory Medicine and Pathology (P.J.J., J.A.B.), and Neurosurgery, College of Medicine (D.F.K.), Mayo Clinic, 200 1st St SW, Rochester, MN 55905
| | - Daniel R. Jakaitis
- From the Departments of Radiology (J.A., J.S.M., M.A.C., C.R.F., S.H., D.R.J., B.S., G.T., D.D., R.K., D.F.K., R.J.M.), Molecular Pharmacology and Experimental Therapeutics (K.M.W., D.S.C.), Biochemistry and Molecular Biology (J.L.S.), Laboratory Medicine and Pathology (P.J.J., J.A.B.), and Neurosurgery, College of Medicine (D.F.K.), Mayo Clinic, 200 1st St SW, Rochester, MN 55905
| | - Bradley Scherer
- From the Departments of Radiology (J.A., J.S.M., M.A.C., C.R.F., S.H., D.R.J., B.S., G.T., D.D., R.K., D.F.K., R.J.M.), Molecular Pharmacology and Experimental Therapeutics (K.M.W., D.S.C.), Biochemistry and Molecular Biology (J.L.S.), Laboratory Medicine and Pathology (P.J.J., J.A.B.), and Neurosurgery, College of Medicine (D.F.K.), Mayo Clinic, 200 1st St SW, Rochester, MN 55905
| | - Gabriel Tutor
- From the Departments of Radiology (J.A., J.S.M., M.A.C., C.R.F., S.H., D.R.J., B.S., G.T., D.D., R.K., D.F.K., R.J.M.), Molecular Pharmacology and Experimental Therapeutics (K.M.W., D.S.C.), Biochemistry and Molecular Biology (J.L.S.), Laboratory Medicine and Pathology (P.J.J., J.A.B.), and Neurosurgery, College of Medicine (D.F.K.), Mayo Clinic, 200 1st St SW, Rochester, MN 55905
| | - Katheryn M. Wininger
- From the Departments of Radiology (J.A., J.S.M., M.A.C., C.R.F., S.H., D.R.J., B.S., G.T., D.D., R.K., D.F.K., R.J.M.), Molecular Pharmacology and Experimental Therapeutics (K.M.W., D.S.C.), Biochemistry and Molecular Biology (J.L.S.), Laboratory Medicine and Pathology (P.J.J., J.A.B.), and Neurosurgery, College of Medicine (D.F.K.), Mayo Clinic, 200 1st St SW, Rochester, MN 55905
| | - Daying Dai
- From the Departments of Radiology (J.A., J.S.M., M.A.C., C.R.F., S.H., D.R.J., B.S., G.T., D.D., R.K., D.F.K., R.J.M.), Molecular Pharmacology and Experimental Therapeutics (K.M.W., D.S.C.), Biochemistry and Molecular Biology (J.L.S.), Laboratory Medicine and Pathology (P.J.J., J.A.B.), and Neurosurgery, College of Medicine (D.F.K.), Mayo Clinic, 200 1st St SW, Rochester, MN 55905
| | - Doo-Sup Choi
- From the Departments of Radiology (J.A., J.S.M., M.A.C., C.R.F., S.H., D.R.J., B.S., G.T., D.D., R.K., D.F.K., R.J.M.), Molecular Pharmacology and Experimental Therapeutics (K.M.W., D.S.C.), Biochemistry and Molecular Biology (J.L.S.), Laboratory Medicine and Pathology (P.J.J., J.A.B.), and Neurosurgery, College of Medicine (D.F.K.), Mayo Clinic, 200 1st St SW, Rochester, MN 55905
| | - Jeffrey L. Salisbury
- From the Departments of Radiology (J.A., J.S.M., M.A.C., C.R.F., S.H., D.R.J., B.S., G.T., D.D., R.K., D.F.K., R.J.M.), Molecular Pharmacology and Experimental Therapeutics (K.M.W., D.S.C.), Biochemistry and Molecular Biology (J.L.S.), Laboratory Medicine and Pathology (P.J.J., J.A.B.), and Neurosurgery, College of Medicine (D.F.K.), Mayo Clinic, 200 1st St SW, Rochester, MN 55905
| | - Paul J. Jannetto
- From the Departments of Radiology (J.A., J.S.M., M.A.C., C.R.F., S.H., D.R.J., B.S., G.T., D.D., R.K., D.F.K., R.J.M.), Molecular Pharmacology and Experimental Therapeutics (K.M.W., D.S.C.), Biochemistry and Molecular Biology (J.L.S.), Laboratory Medicine and Pathology (P.J.J., J.A.B.), and Neurosurgery, College of Medicine (D.F.K.), Mayo Clinic, 200 1st St SW, Rochester, MN 55905
| | - Joshua A. Bornhorst
- From the Departments of Radiology (J.A., J.S.M., M.A.C., C.R.F., S.H., D.R.J., B.S., G.T., D.D., R.K., D.F.K., R.J.M.), Molecular Pharmacology and Experimental Therapeutics (K.M.W., D.S.C.), Biochemistry and Molecular Biology (J.L.S.), Laboratory Medicine and Pathology (P.J.J., J.A.B.), and Neurosurgery, College of Medicine (D.F.K.), Mayo Clinic, 200 1st St SW, Rochester, MN 55905
| | - Ram Kadirvel
- From the Departments of Radiology (J.A., J.S.M., M.A.C., C.R.F., S.H., D.R.J., B.S., G.T., D.D., R.K., D.F.K., R.J.M.), Molecular Pharmacology and Experimental Therapeutics (K.M.W., D.S.C.), Biochemistry and Molecular Biology (J.L.S.), Laboratory Medicine and Pathology (P.J.J., J.A.B.), and Neurosurgery, College of Medicine (D.F.K.), Mayo Clinic, 200 1st St SW, Rochester, MN 55905
| | - David F. Kallmes
- From the Departments of Radiology (J.A., J.S.M., M.A.C., C.R.F., S.H., D.R.J., B.S., G.T., D.D., R.K., D.F.K., R.J.M.), Molecular Pharmacology and Experimental Therapeutics (K.M.W., D.S.C.), Biochemistry and Molecular Biology (J.L.S.), Laboratory Medicine and Pathology (P.J.J., J.A.B.), and Neurosurgery, College of Medicine (D.F.K.), Mayo Clinic, 200 1st St SW, Rochester, MN 55905
| | - Robert J. McDonald
- From the Departments of Radiology (J.A., J.S.M., M.A.C., C.R.F., S.H., D.R.J., B.S., G.T., D.D., R.K., D.F.K., R.J.M.), Molecular Pharmacology and Experimental Therapeutics (K.M.W., D.S.C.), Biochemistry and Molecular Biology (J.L.S.), Laboratory Medicine and Pathology (P.J.J., J.A.B.), and Neurosurgery, College of Medicine (D.F.K.), Mayo Clinic, 200 1st St SW, Rochester, MN 55905
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Villalba RM, Behnke JA, Pare JF, Smith Y. Comparative Ultrastructural Analysis of Thalamocortical Innervation of the Primary Motor Cortex and Supplementary Motor Area in Control and MPTP-Treated Parkinsonian Monkeys. Cereb Cortex 2021; 31:3408-3425. [PMID: 33676368 PMCID: PMC8599722 DOI: 10.1093/cercor/bhab020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 12/29/2020] [Accepted: 01/19/2021] [Indexed: 12/15/2022] Open
Abstract
The synaptic organization of thalamic inputs to motor cortices remains poorly understood in primates. Thus, we compared the regional and synaptic connections of vGluT2-positive thalamocortical glutamatergic terminals in the supplementary motor area (SMA) and the primary motor cortex (M1) between control and MPTP-treated parkinsonian monkeys. In controls, vGluT2-containing fibers and terminal-like profiles invaded layer II-III and Vb of M1 and SMA. A significant reduction of vGluT2 labeling was found in layer Vb, but not in layer II-III, of parkinsonian animals, suggesting a potential thalamic denervation of deep cortical layers in parkinsonism. There was a significant difference in the pattern of synaptic connectivity in layers II-III, but not in layer Vb, between M1 and SMA of control monkeys. However, this difference was abolished in parkinsonian animals. No major difference was found in the proportion of perforated versus macular post-synaptic densities at thalamocortical synapses between control and parkinsonian monkeys in both cortical regions, except for a slight increase in the prevalence of perforated axo-dendritic synapses in the SMA of parkinsonian monkeys. Our findings suggest that disruption of the thalamic innervation of M1 and SMA may underlie pathophysiological changes of the motor thalamocortical loop in the state of parkinsonism.
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Affiliation(s)
- Rosa M Villalba
- Division of Neuropharmacology and Neurological Diseases, Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329, USA
- UDALL Center for Excellence for Parkinson’s Disease, Emory University, Atlanta, GA 30329, USA
| | - Joseph A Behnke
- Division of Neuropharmacology and Neurological Diseases, Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329, USA
- UDALL Center for Excellence for Parkinson’s Disease, Emory University, Atlanta, GA 30329, USA
| | - Jean-Francois Pare
- Division of Neuropharmacology and Neurological Diseases, Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329, USA
- UDALL Center for Excellence for Parkinson’s Disease, Emory University, Atlanta, GA 30329, USA
| | - Yoland Smith
- Division of Neuropharmacology and Neurological Diseases, Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329, USA
- UDALL Center for Excellence for Parkinson’s Disease, Emory University, Atlanta, GA 30329, USA
- Department of Neurology, School of Medicine, Emory University, Atlanta, GA 30329, USA
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D'Cruz N, Vervoort G, Chalavi S, Dijkstra BW, Gilat M, Nieuwboer A. Thalamic morphology predicts the onset of freezing of gait in Parkinson's disease. NPJ Parkinsons Dis 2021; 7:20. [PMID: 33654103 PMCID: PMC7925565 DOI: 10.1038/s41531-021-00163-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 01/14/2021] [Indexed: 11/08/2022] Open
Abstract
The onset of freezing of gait (FOG) in Parkinson's disease (PD) is a critical milestone, marked by a higher risk of falls and reduced quality of life. FOG is associated with alterations in subcortical neural circuits, yet no study has assessed whether subcortical morphology can predict the onset of clinical FOG. In this prospective multimodal neuroimaging cohort study, we performed vertex-based analysis of grey matter morphology in fifty-seven individuals with PD at study entry and two years later. We also explored the behavioral correlates and resting-state functional connectivity related to these local volume differences. At study entry, we found that freezers (N = 12) and persons who developed FOG during the course of the study (converters) (N = 9) showed local inflations in bilateral thalamus in contrast to persons who did not (non-converters) (N = 36). Longitudinally, converters (N = 7) also showed local inflation in the left thalamus, as compared to non-converters (N = 36). A model including sex, daily levodopa equivalent dose, and local thalamic inflation predicted conversion with good accuracy (AUC: 0.87, sensitivity: 88.9%, specificity: 77.8%). Exploratory analyses showed that local thalamic inflations were associated with larger medial thalamic sub-nuclei volumes and better cognitive performance. Resting-state analyses further revealed that converters had stronger thalamo-cortical coupling with limbic and cognitive regions pre-conversion, with a marked reduction in coupling over the two years. Finally, validation using the PPMI cohort suggested FOG-specific non-linear evolution of thalamic local volume. These findings provide markers of, and deeper insights into conversion to FOG, which may foster earlier intervention and better mobility for persons with PD.
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Affiliation(s)
- Nicholas D'Cruz
- KU Leuven, Department of Rehabilitation Sciences, Neurorehabilitation Research Group, B-3000, Leuven, Belgium.
| | - Griet Vervoort
- KU Leuven, Department of Rehabilitation Sciences, Neurorehabilitation Research Group, B-3000, Leuven, Belgium
| | - Sima Chalavi
- KU Leuven, Department of Movement Sciences, Movement Control & Neuroplasticity Research Group, B-3000, Leuven, Belgium
| | - Bauke W Dijkstra
- KU Leuven, Department of Rehabilitation Sciences, Neurorehabilitation Research Group, B-3000, Leuven, Belgium
| | - Moran Gilat
- KU Leuven, Department of Rehabilitation Sciences, Neurorehabilitation Research Group, B-3000, Leuven, Belgium
| | - Alice Nieuwboer
- KU Leuven, Department of Rehabilitation Sciences, Neurorehabilitation Research Group, B-3000, Leuven, Belgium
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8
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Sedaghat K, Gundlach AL, Finkelstein DI. Analysis of morphological and neurochemical changes in subthalamic nucleus neurons in response to a unilateral 6-OHDA lesion of the substantia nigra in adult rats. IBRO Neurosci Rep 2021; 10:96-103. [PMID: 33842916 PMCID: PMC8019994 DOI: 10.1016/j.ibneur.2021.01.002] [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: 10/12/2020] [Revised: 12/28/2020] [Accepted: 01/12/2021] [Indexed: 11/29/2022] Open
Abstract
Background Subthalamic nucleus (STN) neurons undergo changes in their pattern of activity and morphology during the clinical course of Parkinson’s disease (PD). Striatal dopamine depletion and hyperactivity of neurons in the parafascicular nucleus (Pf) of the intralaminar thalamus are predicted to contribute to the STN changes. Objective This study investigated possible morphological and neurochemical changes in STN neurons in a rat model of unilateral, nigral dopamine neuron loss, in relation to previously documented alterations in Pf neurons. Methods Male Sprague-Dawley rats received a unilateral injection of 6-hydroxydopamine (6-OHDA) into the substantia nigra pars compacta (SNpc). Rats were randomly divided into two groups (6/group) for study at 1 and 5 months by post-treatment. The extent of SNpc dopamine neuron damage was assessed in an amphetamine-induced rotation test and postmortem assessment of tyrosine hydroxylase mRNA levels using in situ hybridization histochemistry. Neural cross-sectional measurements and assessment of vesicular glutamate transporter-2 (vGlut2) mRNA levels were performed to measure the impact on neurons in the STN. Results A unilateral SNpc dopaminergic neuron lesion significantly decreased the cross-sectional area of STN neurons ipsilateral to the lesion, at 1 month (P < 0.05) and 5 months (P < 0.01) post-lesion, while bilateral vGlut2 mRNA levels in STN neurons were unaltered. Conclusions Decreased size of STN neurons in the presence of sustained vGlut2 mRNA levels following a unilateral SNpc 6-OHDA lesion, indicate altered STN physiology. This study presents further details of changes within the STN, coincident with observed alterations in Pf neurons and behaviour. Data availability The data associated with the findings of this study are available from the corresponding author upon request.
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Affiliation(s)
- Katayoun Sedaghat
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Victoria, Australia
| | - Andrew L Gundlach
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Victoria, Australia
| | - David I Finkelstein
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Victoria, Australia
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9
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Kim S, Lee Y, Jeon CY, Jin YB, Oh S, Lee C. Observation of magnetic susceptibility changes within the thalamus: a comparative study between healthy and Parkinson’s disease afflicted cynomolgus monkeys using 7 T MRI. J Anal Sci Technol 2019. [DOI: 10.1186/s40543-019-0199-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Although the thalamus is known to modulate basal ganglia function related to motor control activity, the abnormal changes within the thalamus during distinct medical complications have been scarcely investigated. In order to explore the feasibility of assessing iron accumulation in the thalamus as an informative biomarker for Parkinson’s disease (PD), this study was designed to employ quantitative susceptibility mapping using a 7 T magnetic resonance imaging system in cynomolgus monkeys. A 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-injected cynomolgus monkey and a healthy control (HC) were examined by 7 T magnetic resonance imaging. Positron emission tomography with 18F-N-(3-fluoro propyl)-2ß-carboxymethoxy-3ß-(4-iodophenyl) nortropane was also employed to identify the relationship between iron deposits and dopamine depletion. All acquired values were averaged within the volume of interest of the nigrostriatal pathway.
Findings
Compared with the HC, the overall elevation of iron deposition within the thalamus in the Parkinson’s disease model (about 53.81% increase) was similar to that in the substantia nigra (54.81%) region. Substantial susceptibility changes were observed in the intralaminar part of the thalamus (about 70.78% increase). Additionally, we observed that in the Parkinson’s disease model, binding potential values obtained from positron emission tomography were considerably decreased in the thalamus (97.51%) and substantia nigra (92.48%).
Conclusions
The increased iron deposition in the thalamus showed negative correlation with dopaminergic activity in PD, supporting the idea that iron accumulation affects glutaminergic inputs and dopaminergic neurons. This investigation indicates that the remarkable susceptibility changes in the thalamus could be an initial major diagnostic biomarker for Parkinson’s disease-related motor symptoms.
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10
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Swain AJ, Galvan A, Wichmann T, Smith Y. Structural plasticity of GABAergic and glutamatergic networks in the motor thalamus of parkinsonian monkeys. J Comp Neurol 2019; 528:1436-1456. [PMID: 31808567 DOI: 10.1002/cne.24834] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 11/10/2019] [Accepted: 11/19/2019] [Indexed: 12/20/2022]
Abstract
In the primate thalamus, the parvocellular ventral anterior nucleus (VApc) and the centromedian nucleus (CM) receive GABAergic projections from the internal globus pallidus (GPi) and glutamatergic inputs from motor cortices. In this study, we used electron microscopy to assess potential structural changes in GABAergic and glutamatergic microcircuits in the VApc and CM of MPTP-treated parkinsonian monkeys. The intensity of immunostaining for GABAergic markers in VApc and CM did not differ between control and parkinsonian monkeys. In the electron microscope, three major types of terminals were identified in both nuclei: (a) vesicular glutamate transporter 1 (vGluT1)-positive terminals forming asymmetric synapses (type As), which originate from the cerebral cortex, (b) GABAergic terminals forming single symmetric synapses (type S1), which likely arise from the reticular nucleus and GABAergic interneurons, and (c) GABAergic terminals forming multiple symmetric synapses (type S2), which originate from GPi. The density of As terminals outnumbered that of S1 and S2 terminals in VApc and CM of control and parkinsonian animals. No significant change was found in the abundance and synaptic connectivity of S1 and S2 terminals in VApc or CM of MPTP-treated monkeys, while the prevalence of "As" terminals in VApc of parkinsonian monkeys was 51.4% lower than in controls. The cross-sectional area of vGluT1-positive boutons in both VApc and CM of parkinsonian monkeys was significantly larger than in controls, but their pattern of innervation of thalamic cells was not altered. Our findings suggest that the corticothalamic system undergoes significant synaptic remodeling in the parkinsonian state.
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Affiliation(s)
- Ashley J Swain
- Division of Neuropharmacology and Neurological Disorders, Yerkes National Primate Research Center, Atlanta, Georgia.,Udall Center of Excellence for Parkinson's Disease Research, Atlanta, Georgia
| | - Adriana Galvan
- Division of Neuropharmacology and Neurological Disorders, Yerkes National Primate Research Center, Atlanta, Georgia.,Udall Center of Excellence for Parkinson's Disease Research, Atlanta, Georgia.,Department of Neurology, School of Medicine, Emory University, Atlanta, Georgia
| | - Thomas Wichmann
- Division of Neuropharmacology and Neurological Disorders, Yerkes National Primate Research Center, Atlanta, Georgia.,Udall Center of Excellence for Parkinson's Disease Research, Atlanta, Georgia.,Department of Neurology, School of Medicine, Emory University, Atlanta, Georgia
| | - Yoland Smith
- Division of Neuropharmacology and Neurological Disorders, Yerkes National Primate Research Center, Atlanta, Georgia.,Udall Center of Excellence for Parkinson's Disease Research, Atlanta, Georgia.,Department of Neurology, School of Medicine, Emory University, Atlanta, Georgia
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11
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Villalba RM, Pare JF, Lee S, Lee S, Smith Y. Thalamic degeneration in MPTP-treated Parkinsonian monkeys: impact upon glutamatergic innervation of striatal cholinergic interneurons. Brain Struct Funct 2019; 224:3321-3338. [PMID: 31679085 PMCID: PMC6878768 DOI: 10.1007/s00429-019-01967-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 10/04/2019] [Indexed: 12/13/2022]
Abstract
In both Parkinson's disease (PD) patients and MPTP-treated non-human primates, there is a profound neuronal degeneration of the intralaminar centromedian/parafascicular (CM/Pf) thalamic complex. Although this thalamic pathology has long been established in PD (and other neurodegenerative disorders), the impact of CM/Pf cell loss on the integrity of the thalamo-striatal glutamatergic system and its regulatory functions upon striatal neurons remain unknown. In the striatum, cholinergic interneurons (ChIs) are important constituents of the striatal microcircuitry and represent one of the main targets of CM/Pf-striatal projections. Using light and electron microscopy approaches, we have analyzed the potential impact of CM/Pf neuronal loss on the anatomy of the synaptic connections between thalamic terminals (vGluT2-positive) and ChIs neurons in the striatum of parkinsonian monkeys treated chronically with MPTP. The following conclusions can be drawn from our observations: (1) as reported in PD patients, and in our previous monkey study, CM/Pf neurons undergo profound degeneration in monkeys chronically treated with low doses of MPTP. (2) In the caudate (head and body) nucleus of parkinsonian monkeys, there is an increased density of ChIs. (3) Despite the robust loss of CM/Pf neurons, no significant change was found in the density of thalamostriatal (vGluT2-positive) terminals, and in the prevalence of vGluT2-positive terminals in contact with ChIs in parkinsonian monkeys. These findings provide new information about the state of thalamic innervation of the striatum in parkinsonian monkeys with CM/Pf degeneration, and bring up an additional level of intricacy to the consequences of thalamic pathology upon the functional microcircuitry of the thalamostriatal system in parkinsonism. Future studies are needed to assess the importance of CM/Pf neuronal loss, and its potential consequences on the neuroplastic changes induced in the synaptic organization of the thalamostriatal system, in the development of early cognitive impairments in PD.
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Affiliation(s)
- Rosa M Villalba
- Division of Neuropharmacology and Neurological Diseases, Yerkes National Primate Research Center, Emory University, 954, Gatewood Rd NE, Atlanta, GA, 303, USA.
- UDALL Center for Excellence for Parkinson's Disease, Emory University, Atlanta, GA, USA.
| | - Jean-Francois Pare
- Division of Neuropharmacology and Neurological Diseases, Yerkes National Primate Research Center, Emory University, 954, Gatewood Rd NE, Atlanta, GA, 303, USA
- UDALL Center for Excellence for Parkinson's Disease, Emory University, Atlanta, GA, USA
| | - Solah Lee
- Division of Neuropharmacology and Neurological Diseases, Yerkes National Primate Research Center, Emory University, 954, Gatewood Rd NE, Atlanta, GA, 303, USA
- UDALL Center for Excellence for Parkinson's Disease, Emory University, Atlanta, GA, USA
| | - Sol Lee
- Division of Neuropharmacology and Neurological Diseases, Yerkes National Primate Research Center, Emory University, 954, Gatewood Rd NE, Atlanta, GA, 303, USA
- UDALL Center for Excellence for Parkinson's Disease, Emory University, Atlanta, GA, USA
| | - Yoland Smith
- Division of Neuropharmacology and Neurological Diseases, Yerkes National Primate Research Center, Emory University, 954, Gatewood Rd NE, Atlanta, GA, 303, USA
- Department of Neurology, School of Medicine, Emory University, Atlanta, GA, USA
- UDALL Center for Excellence for Parkinson's Disease, Emory University, Atlanta, GA, USA
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12
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State-Dependent Spike and Local Field Synchronization between the Thalamic Parafascicular Nucleus and the Dorsal Striatum in a Rat Model of Parkinson's Disease. Neuroscience 2019; 404:27-38. [DOI: 10.1016/j.neuroscience.2019.01.055] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 01/26/2019] [Accepted: 01/28/2019] [Indexed: 01/29/2023]
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13
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Zheng X, Huang Z, Zhu Y, Liu B, Chen Z, Chen T, Jia L, Li Y, Lei W. Increase in Glutamatergic Terminals in the Striatum Following Dopamine Depletion in a Rat Model of Parkinson's Disease. Neurochem Res 2019; 44:1079-1089. [PMID: 30715657 DOI: 10.1007/s11064-019-02739-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 01/21/2019] [Accepted: 01/21/2019] [Indexed: 12/19/2022]
Abstract
Dopaminergic neuron degeneration is known to give rise to dendrite injury and spine loss of striatal neurons, however, changes of intrastriatal glutamatergic terminals and their synapses after 6-hydroxydopamine (6OHDA)-induced dopamine (DA)-depletion remains controversial. To confirm the effect of striatal DA-depletion on the morphology and protein levels of corticostriatal and thalamostriatal glutamatergic terminals and synapses, immunohistochemistry, immuno-electron microscope (EM), western blotting techniques were performed on Parkinson's disease rat models in this study. The experimental results of this study showed that: (1) 6OHDA-induced DA-depletion resulted in a remarkable increase of Vesicular glutamate transporter 1 (VGlut1) + and Vesicular glutamate transporter 2 (VGlut2)+ terminal densities at both the light microscope (LM) and EM levels, and VGlut1+ and VGlut2+ terminal sizes were shown to be enlarged by immuno-EM; (2) Striatal DA-depletion resulted in a decrease in both the total and axospinous terminal fractions of VGlut1+ terminals, but the axodendritic terminal fraction was not significantly different from the control group. However, total, axospinous and axodendritic terminal fractions for VGlut2+ terminals declined significantly after striatal DA-depletion. (3) Western blotting data showed that striatal DA-depletion up-regulated the expression levels of the VGlut1 and VGlut2 proteins. These results suggest that 6OHDA-induced DA-depletion affects corticostriatal and thalamostriatal glutamatergic synaptic inputs, which are involved in the pathological process of striatal neuron injury induced by DA-depletion.
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Affiliation(s)
- Xuefeng Zheng
- Department of Anatomy, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Ziyun Huang
- Department of Anatomy, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Yaofeng Zhu
- Department of Anatomy, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
- Institute of Medicine, College of Medicine, Jishou University, Jishou, China
| | - Bingbing Liu
- Department of Anesthesiology, Guangdong Second Provincial General Hospital, Guangzhou, China
| | - Zhi Chen
- Department of Anatomy, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Tao Chen
- Department of Anatomy, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Linju Jia
- Department of Anatomy, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Yanmei Li
- Department of Anatomy, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Wanlong Lei
- Department of Anatomy, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China.
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14
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Ugarte A, Corbacho D, Aymerich MS, García-Osta A, Cuadrado-Tejedor M, Oyarzabal J. Impact of Neurodegenerative Diseases on Drug Binding to Brain Tissues: From Animal Models to Human Samples. Neurotherapeutics 2018; 15:742-750. [PMID: 29675823 PMCID: PMC6095788 DOI: 10.1007/s13311-018-0624-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Drug efficacy in the central nervous system (CNS) requires an additional step after crossing the blood-brain barrier. Therapeutic agents must reach their targets in the brain to modulate them; thus, the free drug concentration hypothesis is a key parameter for in vivo pharmacology. Here, we report the impact of neurodegeneration (Alzheimer's disease (AD) and Parkinson's disease (PD) compared with healthy controls) on the binding of 10 known drugs to postmortem brain tissues from animal models and humans. Unbound drug fractions, for some drugs, are significantly different between healthy and injured brain tissues (AD or PD). In addition, drugs binding to brain tissues from AD and PD animal models do not always recapitulate their binding to the corresponding human injured brain tissues. These results reveal potentially relevant implications for CNS drug discovery.
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Affiliation(s)
- Ana Ugarte
- Small Molecule Discovery Platform, Molecular Therapeutics Program, Center for Applied Medical Research (CIMA), University of Navarra, Avenida Pio XII 55, 31008, Pamplona, Spain
| | - David Corbacho
- Small Molecule Discovery Platform, Molecular Therapeutics Program, Center for Applied Medical Research (CIMA), University of Navarra, Avenida Pio XII 55, 31008, Pamplona, Spain
- Imaging Unit and Cancer Imaging Laboratory, University of Navarra, Avenida Pio XII 55, 31008, Pamplona, Spain
| | - María S Aymerich
- Neurobiology of Parkinson's Disease, Neurosciences Division, University of Navarra, Avenida Pio XII 55, 31008, Pamplona, Spain
- Department of Biochemistry and Genetics, School of Sciences, University of Navarra, Irunlarrea 1, 31008, Pamplona, Spain
| | - Ana García-Osta
- Neurobiology of Alzheimer's Disease, Neurosciences Division, Center for Applied Medical Research, University of Navarra, Avenida Pio XII 55, 31008, Pamplona, Spain
| | - Mar Cuadrado-Tejedor
- Neurobiology of Alzheimer's Disease, Neurosciences Division, Center for Applied Medical Research, University of Navarra, Avenida Pio XII 55, 31008, Pamplona, Spain
- Anatomy Department, School of Medicine, University of Navarra, Irunlarrea 1, 31008, Pamplona, Spain
| | - Julen Oyarzabal
- Small Molecule Discovery Platform, Molecular Therapeutics Program, Center for Applied Medical Research (CIMA), University of Navarra, Avenida Pio XII 55, 31008, Pamplona, Spain.
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15
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Tanimura A, Pancani T, Lim SAO, Tubert C, Melendez AE, Shen W, Surmeier DJ. Striatal cholinergic interneurons and Parkinson's disease. Eur J Neurosci 2018; 47:1148-1158. [PMID: 28677242 PMCID: PMC6074051 DOI: 10.1111/ejn.13638] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2017] [Revised: 06/27/2017] [Accepted: 06/30/2017] [Indexed: 11/27/2022]
Abstract
Giant, aspiny cholinergic interneurons (ChIs) have long been known to be key nodes in the striatal circuitry controlling goal-directed actions and habits. In recent years, new experimental approaches, like optogenetics and monosynaptic rabies virus mapping, have expanded our understanding of how ChIs contribute to the striatal activity underlying action selection and the interplay of dopaminergic and cholinergic signaling. These approaches also have begun to reveal how ChI function is distorted in disease states affecting the basal ganglia, like Parkinson's disease (PD). This review gives a brief overview of our current understanding of the functional role played by ChIs in striatal physiology and how this changes in PD. The translational implications of these discoveries, as well as the gaps that remain to be bridged, are discussed as well.
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Affiliation(s)
- Asami Tanimura
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
| | - Tristano Pancani
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
| | - Sean Austin O Lim
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
| | - Cecilia Tubert
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
| | - Alexandra E Melendez
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
| | - Weixing Shen
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
| | - Dalton James Surmeier
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
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16
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Barbagallo G, Arabia G, Morelli M, Nisticò R, Novellino F, Salsone M, Rocca F, Quattrone A, Caracciolo M, Sabatini U, Cherubini A, Quattrone A. Thalamic neurometabolic alterations in tremulous Parkinson's disease: A preliminary proton MR spectroscopy study. Parkinsonism Relat Disord 2017; 43:78-84. [PMID: 28774469 DOI: 10.1016/j.parkreldis.2017.07.028] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Revised: 07/20/2017] [Accepted: 07/26/2017] [Indexed: 10/19/2022]
Abstract
INTRODUCTION The objective of this study was to investigate the thalamic biochemical changes in tremor-dominant Parkinson's disease (tPD) patients in comparison with essential tremor with resting tremor (rET) patients, by using proton MR spectroscopy (1H-MRS). METHODS Fourteen tPD patients, 12 rET patients and 10 controls participated in this study. All patients underwent dopamine transporter single-photon emission computed tomography (DAT-SPECT) with 123I-ioflupane, and a short-echo single-voxel 1H-MRS on a 3T scanner. A voxel of 10 × 15 × 10 mm involving the Vim nucleus was acquired in both thalami of all subjects. Peak areas of N-acetyl-aspartate (NAA), creatine (Cr), glycerophosphocholine (Cho), and glutamate (Glu) were measured for each voxel using LCModel. The NAA/Cr, Cho/Cr, and Glu/Cr ratios were then calculated. RESULTS DAT-SPECT was abnormal in tPD patients, whereas it was normal in rET patients. Patients with tPD showed a significant reduction of NAA/Cr and Cho/Cr in the thalami compared to rET and healthy controls; whereas there were no significant differences between rET patients and controls. The combination of thalamic NAA/Cr and Cho/Cr ratios showed a 100% accuracy in distinguishing tPD patients from rET patients and controls. CONCLUSIONS This study provides preliminary evidence that thalamic neurometabolic abnormalities occur in tremor-dominant phenotype of PD, and suggests that 1H-MRS can help differentiate patients with tPD from those with rET.
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Affiliation(s)
| | - Gennarina Arabia
- Institute of Neurology, University Magna Græcia, Catanzaro, Italy.
| | - Maurizio Morelli
- Institute of Neurology, University Magna Græcia, Catanzaro, Italy.
| | - Rita Nisticò
- Neuroimaging Unit, IBFM, National Research Council, Catanzaro, Italy.
| | - Fabiana Novellino
- Neuroimaging Unit, IBFM, National Research Council, Catanzaro, Italy.
| | - Maria Salsone
- Neuroimaging Unit, IBFM, National Research Council, Catanzaro, Italy.
| | - Federico Rocca
- Neuroimaging Unit, IBFM, National Research Council, Catanzaro, Italy.
| | - Andrea Quattrone
- Institute of Neurology, University Magna Græcia, Catanzaro, Italy.
| | | | - Umberto Sabatini
- Institute of Neuroradiology, University Magna Graecia, Catanzaro, Italy.
| | - Andrea Cherubini
- Neuroimaging Unit, IBFM, National Research Council, Catanzaro, Italy.
| | - Aldo Quattrone
- Institute of Neurology, University Magna Græcia, Catanzaro, Italy; Neuroimaging Unit, IBFM, National Research Council, Catanzaro, Italy.
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17
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Villalba RM, Smith Y. Loss and remodeling of striatal dendritic spines in Parkinson's disease: from homeostasis to maladaptive plasticity? J Neural Transm (Vienna) 2017; 125:431-447. [PMID: 28540422 DOI: 10.1007/s00702-017-1735-6] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Accepted: 05/10/2017] [Indexed: 12/20/2022]
Abstract
In Parkinson's disease (PD) patients and animal models of PD, the progressive degeneration of the nigrostriatal dopamine (DA) projection leads to two major changes in the morphology of striatal projection neurons (SPNs), i.e., a profound loss of dendritic spines and the remodeling of axospinous glutamatergic synapses. Striatal spine loss is an early event tightly associated with the extent of striatal DA denervation, but not the severity of parkinsonian motor symptoms, suggesting that striatal spine pruning might be a form of homeostatic plasticity that compensates for the loss of striatal DA innervation and the resulting dysregulation of corticostriatal glutamatergic transmission. On the other hand, the remodeling of axospinous corticostriatal and thalamostriatal glutamatergic synapses might represent a form of late maladaptive plasticity that underlies changes in the strength and plastic properties of these afferents and the resulting increased firing and bursting activity of striatal SPNs in the parkinsonian state. There is also evidence that these abnormal synaptic connections might contribute to the pathophysiology of L-DOPA-induced dyskinesia. Despite the significant advances made in this field over the last thirty years, many controversial issues remain about the striatal SPN subtypes affected, the role of spine changes in the altered activity of SPNs in the parkinsonisn state, and the importance of striatal spine plasticity in the pathophysiology of L-DOPA-induced dyskinesia. In this review, we will examine the current state of knowledge of these issues, discuss the limitations of the animal models used to address some of these questions, and assess the relevance of data from animal models to the human-diseased condition.
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Affiliation(s)
- Rosa M Villalba
- Yerkes National Primate Research Center, Emory University, 954 Gatewood Rd. NE, Atlanta, GA, 30329, USA. .,UDALL Center of Excellence for Parkinson's Disease, Emory University, Atlanta, GA, USA.
| | - Yoland Smith
- Yerkes National Primate Research Center, Emory University, 954 Gatewood Rd. NE, Atlanta, GA, 30329, USA.,UDALL Center of Excellence for Parkinson's Disease, Emory University, Atlanta, GA, USA.,Department of Neurology, Emory University, Atlanta, GA, USA
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18
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Wang M, Qu Q, He T, Li M, Song Z, Chen F, Zhang X, Xie J, Geng X, Yang M, Wang X, Lei C, Hou Y. Distinct temporal spike and local field potential activities in the thalamic parafascicular nucleus of parkinsonian rats during rest and limb movement. Neuroscience 2016; 330:57-71. [PMID: 27238892 DOI: 10.1016/j.neuroscience.2016.05.031] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Revised: 05/03/2016] [Accepted: 05/18/2016] [Indexed: 11/15/2022]
Abstract
Several studies have suggested that the thalamic centromedian-parafascicular (CM/PF or the PF in rodents) is implicated in the pathophysiology of Parkinson's disease (PD). However, inconsistent changes in the neuronal firing rate and pattern have been reported in parkinsonian animals. To investigate the impact of a dopaminergic cell lesion on PF extracellular discharge in behaving rats, the PF neural activities in the spike and local field potential (LFP) were recorded in unilaterally 6-hydroxydopamine- (6-OHDA) lesioned and neurologically intact control rats during rest and limb movement. During rest, the two PF neuronal subtypes was less spontaneously active, with no difference in the spike firing rates between the control and lesioned rats; only the lesioned rats reshaped their spike firing pattern. Furthermore, the simultaneously recorded LFP in the lesioned rats exhibited a significant increase in power at 12-35 and 35-70Hz and a decrease in power at 0.7-12Hz. During the execution of a voluntary movement, two subtypes of PF neurons were identified by a rapid increase in the discharge activity in both the control and lesioned rats. However, dopamine lesioning was associated with a decrease in neuronal spiking fire rate and reshaping in the firing pattern in the PF. The simultaneously recorded LFP activity exhibited a significant increase in power at 12-35Hz and a decrease in power at 0.7-12Hz compared with the control rats. These findings indicate that 6-OHDA induces modifications in PF spike and LFP activities in rats during rest and movement and suggest that PF dysfunction may be an important contributor to the pathophysiology of parkinsonian motor impairment.
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Affiliation(s)
- Min Wang
- Key Laboratory of Animal Resistance of Shandong Province, College of Life Science, Shandong Normal University, Jinan 250014, People's Republic of China.
| | - Qingyang Qu
- Key Laboratory of Animal Resistance of Shandong Province, College of Life Science, Shandong Normal University, Jinan 250014, People's Republic of China
| | - Tingting He
- Key Laboratory of Animal Resistance of Shandong Province, College of Life Science, Shandong Normal University, Jinan 250014, People's Republic of China
| | - Min Li
- Key Laboratory of Animal Resistance of Shandong Province, College of Life Science, Shandong Normal University, Jinan 250014, People's Republic of China
| | - Zhimin Song
- Center for Behavioral Neuroscience, Neuroscience Institute, Georgia State University, Atlanta, GA 30302, United States
| | - Feiyu Chen
- Key Laboratory of Animal Resistance of Shandong Province, College of Life Science, Shandong Normal University, Jinan 250014, People's Republic of China
| | - Xiao Zhang
- Key Laboratory of Animal Resistance of Shandong Province, College of Life Science, Shandong Normal University, Jinan 250014, People's Republic of China
| | - Jinlu Xie
- Key Laboratory of Animal Resistance of Shandong Province, College of Life Science, Shandong Normal University, Jinan 250014, People's Republic of China
| | - Xiwen Geng
- Key Laboratory of Animal Resistance of Shandong Province, College of Life Science, Shandong Normal University, Jinan 250014, People's Republic of China
| | - Maoquan Yang
- Key Laboratory of Animal Resistance of Shandong Province, College of Life Science, Shandong Normal University, Jinan 250014, People's Republic of China
| | - Xiusong Wang
- Key Laboratory of Animal Resistance of Shandong Province, College of Life Science, Shandong Normal University, Jinan 250014, People's Republic of China
| | - Chengdong Lei
- Key Laboratory of Animal Resistance of Shandong Province, College of Life Science, Shandong Normal University, Jinan 250014, People's Republic of China
| | - Yabing Hou
- Key Laboratory of Animal Resistance of Shandong Province, College of Life Science, Shandong Normal University, Jinan 250014, People's Republic of China
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Koos BJ, Rajaee A, Ibe B, Guerra C, Kruger L. Thalamic mediation of hypoxic respiratory depression in lambs. Am J Physiol Regul Integr Comp Physiol 2016; 310:R586-95. [PMID: 26818057 PMCID: PMC4867384 DOI: 10.1152/ajpregu.00412.2015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Accepted: 01/27/2016] [Indexed: 11/22/2022]
Abstract
Immaturity of respiratory controllers in preterm infants dispose to recurrent apnea and oxygen deprivation. Accompanying reductions in brain oxygen tensions evoke respiratory depression, potentially exacerbating hypoxemia. Central respiratory depression during moderate hypoxia is revealed in the ventilatory decline following initial augmentation. This study determined whether the thalamic parafascicular nuclear (Pf) complex involved in adult nociception and sensorimotor regulation (Bentivoglio M, Balerecia G, Kruger L. Prog Brain Res 87: 53-80, 1991) also becomes a postnatal controller of hypoxic ventilatory decline. Respiratory responses to moderate isocapnic hypoxia were studied in conscious lambs. Hypoxic ventilatory decline was compared with peak augmentation. Pf and/or adjacent thalamic structures were destroyed by the neuron-specific toxin ibotenic acid (IB). IB lesions involving the thalamic Pf abolished hypoxic ventilatory decline. Lesions of adjacent thalamic nuclei that spared Pf and control injections of vehicle failed to blunt hypoxic respiratory depression. Our findings reveal that the thalamic Pf region is a critical controller of hypoxic ventilatory depression and thus a key target for exploring molecular concomitants of forebrain pathways regulating hypoxic ventilatory depression in early development.
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Affiliation(s)
- Brian J Koos
- Department of Obstetrics & Gynecology, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, California;
| | - Arezoo Rajaee
- Department of Obstetrics & Gynecology, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, California
| | - Basil Ibe
- Department of Pediatrics, C. W. Steers Biological Resource Center, Los Angeles Biomedical Research Institute, Harbor-University of California Los Angeles Medical Center, Torrance, California; and
| | - Catalina Guerra
- C. W. Steers Biological Resource Center, Los Angeles Biomedical Research Institute, Harbor-University of California Los Angeles Medical Center, Torrance, California
| | - Lawrence Kruger
- Department of Neurobiology, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, California
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Nouraei N, Zarger L, Weilnau JN, Han J, Mason DM, Leak RK. Investigation of the therapeutic potential of N-acetyl cysteine and the tools used to define nigrostriatal degeneration in vivo. Toxicol Appl Pharmacol 2016; 296:19-30. [PMID: 26879220 DOI: 10.1016/j.taap.2016.02.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2015] [Revised: 02/02/2016] [Accepted: 02/10/2016] [Indexed: 12/22/2022]
Abstract
The glutathione precursor N-acetyl-L-cysteine (NAC) is currently being tested on Parkinson's patients for its neuroprotective properties. Our studies have shown that NAC can elicit protection in glutathione-independent manners in vitro. Thus, the goal of the present study was to establish an animal model of NAC-mediated protection in which to dissect the underlying mechanism. Mice were infused intrastriatally with the oxidative neurotoxicant 6-hydroxydopamine (6-OHDA; 4 μg) and administered NAC intraperitoneally (100mg/kg). NAC-treated animals exhibited higher levels of the dopaminergic terminal marker tyrosine hydroxylase (TH) in the striatum 10d after 6-OHDA. As TH expression is subject to stress-induced modulation, we infused the tracer FluoroGold into the striatum to retrogradely label nigrostriatal projection neurons. As expected, nigral FluoroGold staining and cell counts of FluoroGold(+) profiles were both more sensitive measures of nigrostriatal degeneration than measurements relying on TH alone. However, NAC failed to protect dopaminergic neurons 3 weeks following 6-OHDA, an effect verified by four measures: striatal TH levels, nigral TH levels, nigral TH(+) cell counts, and nigral FluoroGold levels. Some degree of mild toxicity of FluoroGold and NAC was evident, suggesting that caution must be exercised when relying on FluoroGold as a neuron-counting tool and when designing experiments with long-term delivery of NAC--such as clinical trials on patients with chronic disorders. Finally, the strengths and limitations of the tools used to define nigrostriatal degeneration are discussed.
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Affiliation(s)
- Negin Nouraei
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA, United States
| | - Lauren Zarger
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA, United States
| | - Justin N Weilnau
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA, United States
| | - Jimin Han
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA, United States
| | - Daniel M Mason
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA, United States
| | - Rehana K Leak
- Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA, United States.
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Chassain C, Melon C, Salin P, Vitale F, Couraud S, Durif F, Kerkerian-Le Goff L, Gubellini P. Metabolic, synaptic and behavioral impact of 5-week chronic deep brain stimulation in hemiparkinsonian rats. J Neurochem 2015; 136:1004-16. [PMID: 26576509 DOI: 10.1111/jnc.13438] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Revised: 10/26/2015] [Accepted: 11/05/2015] [Indexed: 01/19/2023]
Abstract
The long-term effects and action mechanisms of subthalamic nucleus (STN) high-frequency stimulation (HFS) for Parkinson's disease still remain poorly characterized, mainly due to the lack of experimental models relevant to clinical application. To address this issue, we performed a multilevel study in freely moving hemiparkinsonian rats undergoing 5-week chronic STN HFS, using a portable constant-current microstimulator. In vivo metabolic neuroimaging by (1) H-magnetic resonance spectroscopy (11.7 T) showed that STN HFS normalized the tissue levels of the neurotransmission-related metabolites glutamate, glutamine and GABA in both the striatum and substantia nigra reticulata (SNr), which were significantly increased in hemiparkinsonian rats, but further decreased nigral GABA levels below control values; taurine levels, which were not affected in hemiparkinsonian rats, were significantly reduced. Slice electrophysiological recordings revealed that STN HFS was, uniquely among antiparkinsonian treatments, able to restore both forms of corticostriatal synaptic plasticity, i.e. long-term depression and potentiation, which were impaired in hemiparkinsonian rats. Behavior analysis (staircase test) showed a progressive recovery of motor skill during the stimulation period. Altogether, these data show that chronic STN HFS efficiently counteracts metabolic and synaptic defects due to dopaminergic lesion in both the striatum and SNr. Comparison of chronic STN HFS with acute and subchronic treatment further suggests that the long-term benefits of this treatment rely both on the maintenance of acute effects and on delayed actions on the basal ganglia network. We studied the effects of chronic (5 weeks) continuous subthalamic nucleus (STN) high-frequency stimulation (HFS) in hemiparkinsonian rats. The levels of glutamate and GABA in the striatum () and substantia nigra reticulata (SNr) (), measured by in vivo proton magnetic resonance spectroscopy ((1) H-MRS), were increased by 6-hydroxydopamine (6-OHDA) lesion, which also disrupted corticostriatal synaptic plasticity () and impaired forepaw skill () in the staircase test. Five-week STN HFS normalized glutamate and GABA levels and restored both synaptic plasticity and motor function. A partial behavioral recovery was observed at 2-week STN HFS.
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Affiliation(s)
- Carine Chassain
- Centre Hospitalier Universitaire (CHU) Clermont-Ferrand and Université d'Auvergne, Clermont-Ferrand, France
| | - Christophe Melon
- Institut de Biologie du Développement de Marseille (IBDM) UMR7288, Aix-Marseille Université, CNRS, Marseille, France
| | - Pascal Salin
- Institut de Biologie du Développement de Marseille (IBDM) UMR7288, Aix-Marseille Université, CNRS, Marseille, France
| | - Flora Vitale
- Institut de Biologie du Développement de Marseille (IBDM) UMR7288, Aix-Marseille Université, CNRS, Marseille, France
| | - Sébastien Couraud
- Institut de Biologie du Développement de Marseille (IBDM) UMR7288, Aix-Marseille Université, CNRS, Marseille, France
| | - Franck Durif
- Centre Hospitalier Universitaire (CHU) Clermont-Ferrand and Université d'Auvergne, Clermont-Ferrand, France
| | - Lydia Kerkerian-Le Goff
- Institut de Biologie du Développement de Marseille (IBDM) UMR7288, Aix-Marseille Université, CNRS, Marseille, France
| | - Paolo Gubellini
- Institut de Biologie du Développement de Marseille (IBDM) UMR7288, Aix-Marseille Université, CNRS, Marseille, France
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Villalba RM, Mathai A, Smith Y. Morphological changes of glutamatergic synapses in animal models of Parkinson's disease. Front Neuroanat 2015; 9:117. [PMID: 26441550 PMCID: PMC4585113 DOI: 10.3389/fnana.2015.00117] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Accepted: 08/17/2015] [Indexed: 02/05/2023] Open
Abstract
The striatum and the subthalamic nucleus (STN) are the main entry doors for extrinsic inputs to reach the basal ganglia (BG) circuitry. The cerebral cortex, thalamus and brainstem are the key sources of glutamatergic inputs to these nuclei. There is anatomical, functional and neurochemical evidence that glutamatergic neurotransmission is altered in the striatum and STN of animal models of Parkinson’s disease (PD) and that these changes may contribute to aberrant network neuronal activity in the BG-thalamocortical circuitry. Postmortem studies of animal models and PD patients have revealed significant pathology of glutamatergic synapses, dendritic spines and microcircuits in the striatum of parkinsonians. More recent findings have also demonstrated a significant breakdown of the glutamatergic corticosubthalamic system in parkinsonian monkeys. In this review, we will discuss evidence for synaptic glutamatergic dysfunction and pathology of cortical and thalamic inputs to the striatum and STN in models of PD. The potential functional implication of these alterations on synaptic integration, processing and transmission of extrinsic information through the BG circuits will be considered. Finally, the significance of these pathological changes in the pathophysiology of motor and non-motor symptoms in PD will be examined.
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Affiliation(s)
- Rosa M Villalba
- Yerkes National Primate Research Center, Emory University Atlanta, GA, USA ; UDALL Center of Excellence for Parkinson's Disease, Emory University Atlanta, GA, USA
| | - Abraham Mathai
- Yerkes National Primate Research Center, Emory University Atlanta, GA, USA ; UDALL Center of Excellence for Parkinson's Disease, Emory University Atlanta, GA, USA
| | - Yoland Smith
- Yerkes National Primate Research Center, Emory University Atlanta, GA, USA ; UDALL Center of Excellence for Parkinson's Disease, Emory University Atlanta, GA, USA ; Department of Neurology, Emory University Atlanta, GA, USA
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Villalba RM, Wichmann T, Smith Y. Neuronal loss in the caudal intralaminar thalamic nuclei in a primate model of Parkinson's disease. Brain Struct Funct 2014; 219:381-94. [PMID: 23508713 PMCID: PMC3864539 DOI: 10.1007/s00429-013-0507-9] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2012] [Accepted: 01/06/2013] [Indexed: 02/07/2023]
Abstract
In light of postmortem human studies showing extensive degeneration of the center median (CM) and parafascicular (Pf) thalamic nuclei in Parkinson's disease patients, the present study assessed the extent of neuronal loss in CM/Pf of non-human primates that were rendered parkinsonian by repeated injections of low doses of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). In order to determine the course of CM/Pf degeneration during the MPTP intoxication, motor-asymptomatic animals with partial striatal dopamine denervation were also used. The Cavalieri's principle for volume estimation and the unbiased stereological cell count method with the optical dissector technique were used to estimate the total number of neurons in the CM/Pf. We found substantial neurons loss in the CM/Pf in both, motor-symptomatic MPTP-treated monkeys in which the striatal dopamine innervation was reduced by more than 80%, and in motor-asymptomatic MPTP-treated animals with 40-50% striatal dopamine loss. In MPTP-treated parkinsonian monkeys, 60 and 62% neurons loss was found in CM and Pf, respectively, while partially dopamine-depleted asymptomatic animals displayed 59 and 52% neurons loss in the CM and Pf, respectively. Thus, our study demonstrates that the CM/Pf neurons loss is an early phenomenon that occurs prior to the development of parkinsonian motor symptoms in these animals. In contrast, the neighboring mediodorsal nucleus of the thalamus was only mildly affected (18% neurons loss) in the parkinsonian monkeys. Together with recent findings about the possible role of the CM/Pf-striatal system in cognition, our findings suggest that the pathology of the thalamostriatal system may precede the development of motor symptoms in PD, and may account for some of the cognitive deficits in attentional set-shifting often seen in these patients. Future studies in this animal model, and in monkeys with selective lesion of CM or Pf, are needed to further elucidate the role of the CM/Pf-striatal system in normal and parkinsonian conditions.
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Affiliation(s)
- R. M. Villalba
- Yerkes National Primate Research Center, Emory University, 954 Gatewood Rd. NE, Atlanta, GA 30329, USA, , Udall Center of Excellence for Parkinson's Disease Research, Emory University, Atlanta, GA, USA
| | - T. Wichmann
- Yerkes National Primate Research Center, Emory University, 954 Gatewood Rd. NE, Atlanta, GA 30329, USA, , Udall Center of Excellence for Parkinson's Disease Research, Emory University, Atlanta, GA, USADepartment of Neurology, Emory University, Atlanta, GA, USA
| | - Y. Smith
- Yerkes National Primate Research Center, Emory University, 954 Gatewood Rd. NE, Atlanta, GA 30329, USA, , Udall Center of Excellence for Parkinson's Disease Research, Emory University, Atlanta, GA, USA, Department of Neurology, Emory University, Atlanta, GA, USA
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25
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Arbuthnott GW. Thalamostriatal synapses-another substrate for dopamine action? PROGRESS IN BRAIN RESEARCH 2014; 211:1-11. [PMID: 24968774 DOI: 10.1016/b978-0-444-63425-2.00001-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Over the years since the discovery of dopamine in the neostriatum, we have learned much about the anatomy of this large subcortical nucleus. In rodents, it is one nucleus penetrated by many fibers from the cerebral cortex. In larger animals and in humans, the area is split by a bundle of mainly corticofugal axons into the caudate nucleus and putamen. Dopamine input to both is similar and except for the details of cortical afferents to the two parts the striatum seems to act as one structure. Its main function is expected to be the transfer of the information carried in its cortical inputs onward through the basal ganglia. Diseases of this area of brain are associated with movement disorders and much is made of the action of dopamine on the long-term stability of corticostriatal synapses. The cortex is not at all the only input to the area, however, and the thalamus has almost as many synapses with striatal output neurons as has the cortex. This chapter summarizes the contributions to the study of the involvement of thalamostriatal inputs presented at Dopamine 2013 and emphasizes that this input, though largely ignored, has important lessons for those interested in understanding the function of the basal ganglia.
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Affiliation(s)
- Gordon W Arbuthnott
- Brain Mechanisms for Behaviour Unit, OIST Graduate University, Onna-son, Kunigami-gun, Okinawa, Japan.
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26
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Favier M, Carcenac C, Drui G, Boulet S, El Mestikawy S, Savasta M. High-frequency stimulation of the subthalamic nucleus modifies the expression of vesicular glutamate transporters in basal ganglia in a rat model of Parkinson's disease. BMC Neurosci 2013; 14:152. [PMID: 24308494 PMCID: PMC4234365 DOI: 10.1186/1471-2202-14-152] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Accepted: 11/27/2013] [Indexed: 11/18/2022] Open
Abstract
Background It has been suggested that glutamatergic system hyperactivity may be related to the pathogenesis of Parkinson’s disease (PD). Vesicular glutamate transporters (VGLUT1-3) import glutamate into synaptic vesicles and are key anatomical and functional markers of glutamatergic excitatory transmission. Both VGLUT1 and VGLUT2 have been identified as definitive markers of glutamatergic neurons, but VGLUT 3 is also expressed by non glutamatergic neurons. VGLUT1 and VGLUT2 are thought to be expressed in a complementary manner in the cortex and the thalamus (VL/VM), in glutamatergic neurons involved in different physiological functions. Chronic high-frequency stimulation (HFS) of the subthalamic nucleus (STN) is the neurosurgical therapy of choice for the management of motor deficits in patients with advanced PD. STN-HFS is highly effective, but its mechanisms of action remain unclear. This study examines the effect of STN-HFS on VGLUT1-3 expression in different brain nuclei involved in motor circuits, namely the basal ganglia (BG) network, in normal and 6-hydroxydopamine (6-OHDA) lesioned rats. Results Here we report that: 1) Dopamine(DA)-depletion did not affect VGLUT1 and VGLUT3 expression but significantly decreased that of VGLUT2 in almost all BG structures studied; 2) STN-HFS did not change VGLUT1-3 expression in the different brain areas of normal rats while, on the contrary, it systematically induced a significant increase of their expression in DA-depleted rats and 3) STN-HFS reversed the decrease in VGLUT2 expression induced by the DA-depletion. Conclusions These results show for the first time a comparative analysis of changes of expression for the three VGLUTs induced by STN-HFS in the BG network of normal and hemiparkinsonian rats. They provide evidence for the involvement of VGLUT2 in the modulation of BG cicuits and in particular that of thalamostriatal and thalamocortical pathways suggesting their key role in its therapeutic effects for alleviating PD motor symptoms.
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Affiliation(s)
- Mathieu Favier
- Institut National de la Santé et de la Recherche Médicale, Unité 836, Grenoble Institut des Neurosciences, Equipe Dynamique et Physiopathologie des Ganglions de la Base, Grenoble F-38043, Cedex 9, France.
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Castaño JG, González C, Obeso JA, Rodriguez M. Molecular Pathogenesis and Pathophysiology of Parkinson’s Disease: New Targets for New Therapies. EMERGING DRUGS AND TARGETS FOR PARKINSON’S DISEASE 2013. [DOI: 10.1039/9781849737357-00026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Parkinson’s disease (PD) is a complex chronic neurodegenerative disease of unknown etiology. A conceptual framework for all chronic diseases involves a series of channels or pathways (aging, genetic, environment, oxidative stress, mitochondrial damage, protein aggregation, etc.) and their interactions. Those channels with specificities may explain the ‘developmental’ program that through transcriptional reprogramming results in stressed dopamine neurons that eventually become dysfunctional or die, giving rise to the clinical manifestations of PD. In Chapter 2 we review the molecular mechanisms of those channels that may be implicated in the pathogenesis of PD and the pathophysiology of the disease based on the anatomo‐physiological complexity of the basal ganglia. This illustrates that understanding the molecular mechanisms of a disease may not be enough, or we have to reach an adequate system level to understand the disease process. Finally, we suggest that common therapies used for the treatment of other chronic diseases may be useful for the treatment (or help to advance the understanding) of PD, as well as new targets for new therapies that may be useful in the prevention of, or to stop the progression of, PD and other synucleinopathies.
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Affiliation(s)
- José G. Castaño
- Departamento de Bioquímica, Instituto de Investigaciones Biomédicas “Alberto Sols”, Facultad de Medicina Universidad Autónoma de Madrid Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas Madrid Spain
| | - Carmen González
- Departamento de Farmacologia, Facultad de Medicina Universidad de Castilla‐La Mancha Albacete Spain
| | - José A. Obeso
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas Madrid Spain
- Laboratorio de Trastornos del Movimiento, Centro de Investigación Médica Aplicada University of Navarra Pamplona Spain
| | - Manuel Rodriguez
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas Madrid Spain
- Laboratory of Neurobiology and Experimental Neurology, Department of Physiology, Faculty of Medicine University of La Laguna Tenerife Canary Islands
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Visualization of fast calcium oscillations in the parafascicular nucleus. Pflugers Arch 2013; 465:1327-40. [PMID: 23588378 DOI: 10.1007/s00424-013-1264-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2012] [Revised: 03/01/2013] [Accepted: 03/07/2013] [Indexed: 10/27/2022]
Abstract
The parafascicular nucleus (Pf) is an ascending target of the pedunculopontine nucleus (PPN) and is part of the "non-specific" intralaminar thalamus. The PPN, part of the reticular activating system, is mainly involved in waking and rapid eye movement sleep. Gamma oscillations are evident in all Pf neurons and mediated by high threshold voltage-dependent N- and P/Q-type calcium channels. We tested the hypothesis that high-speed calcium imaging would reveal calcium-mediated oscillations in synchrony with patch clamp recorded oscillations during depolarizing current ramps. Patch-clamped 9 to 19-day-old rat Pf neurons (n = 148, dye filled n = 61, control n = 87) were filled with Fura 2, Bis Fura, or Oregon Green BAPTA-1. Calcium transients were generated during depolarizing current ramps and visualized with a high-speed, wide-field fluorescence imaging system. Cells manifested calcium transients with oscillations in both somatic and proximal dendrite fluorescence recordings. Fluorescent calcium transients were blocked with the nonspecific calcium channel blocker, cadmium, or the combination of ω-Agatoxin-IVA (AgA), a specific P/Q-type calcium channel blocker and ω-conotoxin-GVIA (CgTx), a specific N-type calcium channel blocker. We developed a viable methodology for studying high-speed oscillations without the use of multi-photon imaging systems.
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Morales I, Sabate M, Rodriguez M. Striatal glutamate induces retrograde excitotoxicity and neuronal degeneration of intralaminar thalamic nuclei: their potential relevance for Parkinson's disease. Eur J Neurosci 2013; 38:2172-82. [DOI: 10.1111/ejn.12205] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2013] [Revised: 02/27/2013] [Accepted: 02/28/2013] [Indexed: 01/23/2023]
Affiliation(s)
| | - Magdalena Sabate
- Department of Pharmacology and Physical Medicine; Faculty of Medicine; University of La Laguna; Service of Rehabilitation HUC; La Laguna; Tenerife; Canary Islands; Spain
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Yeo S, Choi YG, Hong YM, Lim S. Neuroprotective changes of thalamic degeneration-related gene expression by acupuncture in an MPTP mouse model of parkinsonism: microarray analysis. Gene 2012; 515:329-38. [PMID: 23235115 DOI: 10.1016/j.gene.2012.12.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2012] [Revised: 10/12/2012] [Accepted: 12/02/2012] [Indexed: 01/18/2023]
Abstract
Acupuncture stimulations at GB34 and LR3 inhibit the reduction of tyrosine hydroxylase in the nigrostriatal dopaminergic neurons in the parkinsonism animal models. Especially, behavioral tests showed that acupuncture stimulations improved the motor dysfunction in a previous study by almost 87.7%. The thalamus is a crucial area for the motor circuit and has been identified as one of the most markedly damaged areas in Parkinson's disease (PD), so acupuncture stimulations might also have an effect on the thalamic damage. In this study, gene expression changes following acupuncture at the acupoints were investigated in the thalamus of a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced parkinsonism model using a whole transcript array. It was confirmed that acupuncture at these acupoints could inhibit the decrease of tyrosine hydroxylase in the thalamic regions of the MPTP model, while acupuncture at the non-acupoints could not suppress this decrease by its level shown in the acupoints. GeneChip gene array analysis showed that 18 (5 annotated genes: Dnase1l2, Dusp4, Mafg, Ndph and Pgm5) of the probes down-regulated in MPTP, as compared to the control, were exclusively up-regulated by acupuncture at the acupoints, but not at the non-acupoints. In addition, 14 (3 annotated genes; Serinc2, Sp2 and Ucp2) of the probes up-regulated in MPTP, as compared to the control, were exclusively down-regulated by acupuncture at the acupoints, but not at the non-acupoints. The expression levels of the representative genes in the microarray were validated by real-time RT-PCR. These results suggest that the 32 probes (8 annotated genes) which are affected by MPTP and acupuncture may be responsible for exerting the inhibitory effect of acupuncture in the thalamus which can be damaged by MPTP intoxication.
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Affiliation(s)
- Sujung Yeo
- Research Group of Pain and Neuroscience, WHO Collaborating Center for Traditional Medicine, East-West Medical Research Institute, Kyung Hee University, Seoul, Republic of Korea
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Rubin JE, McIntyre CC, Turner RS, Wichmann T. Basal ganglia activity patterns in parkinsonism and computational modeling of their downstream effects. Eur J Neurosci 2012; 36:2213-28. [PMID: 22805066 DOI: 10.1111/j.1460-9568.2012.08108.x] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The availability of suitable animal models and the opportunity to record electrophysiologic data in movement disorder patients undergoing neurosurgical procedures has allowed researchers to investigate parkinsonism-related changes in neuronal firing patterns in the basal ganglia and associated areas of the thalamus and cortex. These studies have shown that parkinsonism is associated with increased activity in the basal ganglia output nuclei, along with increases in burst discharges, oscillatory firing and synchronous firing patterns throughout the basal ganglia. Computational approaches have the potential to play an important role in the interpretation of these data. Such efforts can provide a formalized view of neuronal interactions in the network of connections between the basal ganglia, thalamus, and cortex, allow for the exploration of possible contributions of particular network components to parkinsonism, and potentially result in new conceptual frameworks and hypotheses that can be subjected to biological testing. It has proven very difficult, however, to integrate the wealth of the experimental findings into coherent models of the disease. In this review, we provide an overview of the abnormalities in neuronal activity that have been associated with parkinsonism. Subsequently, we discuss some particular efforts to model the pathophysiologic mechanisms that may link abnormal basal ganglia activity to the cardinal parkinsonian motor signs and may help to explain the mechanisms underlying the therapeutic efficacy of deep brain stimulation for Parkinson's disease. We emphasize the logical structure of these computational studies, making clear the assumptions from which they proceed and the consequences and predictions that follow from these assumptions.
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Affiliation(s)
- Jonathan E Rubin
- Department of Mathematics and Center for the Neural Basis of Cognition, University of Pittsburgh, 301 Thackeray Hall, Pittsburgh, PA 15260, USA
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Walker RH, Moore C, Davies G, Dirling LB, Koch RJ, Meshul CK. Effects of subthalamic nucleus lesions and stimulation upon corticostriatal afferents in the 6-hydroxydopamine-lesioned rat. PLoS One 2012; 7:e32919. [PMID: 22427909 PMCID: PMC3299711 DOI: 10.1371/journal.pone.0032919] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2011] [Accepted: 02/06/2012] [Indexed: 12/27/2022] Open
Abstract
Abnormalities of striatal glutamate neurotransmission may play a role in the pathophysiology of Parkinson's disease and may respond to neurosurgical interventions, specifically stimulation or lesioning of the subthalamic nucleus (STN). The major glutamatergic afferent pathways to the striatum are from the cortex and thalamus, and are thus likely to be sources of striatal neuronally-released glutamate. Corticostriatal terminals can be distinguished within the striatum at the electron microscopic level as their synaptic vesicles contain the vesicular glutamate transporter, VGLUT1. The majority of terminals which are immunolabeled for glutamate but are not VGLUT1 positive are likely to be thalamostriatal afferents. We compared the effects of short term, high frequency, STN stimulation and lesioning in 6-hydroxydopamine (6OHDA)-lesioned rats upon striatal terminals immunolabeled for both presynaptic glutamate and VGLUT1. 6OHDA lesions resulted in a small but significant increase in the proportions of VGLUT1-labeled terminals making synapses on dendritic shafts rather than spines. STN stimulation for one hour, but not STN lesions, increased the proportion of synapses upon spines. The density of presynaptic glutamate immuno-gold labeling was unchanged in both VGLUT1-labeled and -unlabeled terminals in 6OHDA-lesioned rats compared to controls. Rats with 6OHDA lesions+STN stimulation showed a decrease in nerve terminal glutamate immuno-gold labeling in both VGLUT1-labeled and -unlabeled terminals. STN lesions resulted in a significant decrease in the density of presynaptic immuno-gold-labeled glutamate only in VGLUT1-labeled terminals. STN interventions may achieve at least part of their therapeutic effect in PD by normalizing the location of corticostriatal glutamatergic terminals and by altering striatal glutamatergic neurotransmission.
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Affiliation(s)
- Ruth H Walker
- Department of Neurology, James J Peters Veterans Affairs Medical Center, Bronx, New York, United States of America.
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Lin LH, Nitschke Dragon D, Talman WT. Collateral damage and compensatory changes after injection of a toxin targeting neurons with the neurokinin-1 receptor in the nucleus tractus solitarii of rat. J Chem Neuroanat 2012; 43:141-8. [PMID: 22414622 DOI: 10.1016/j.jchemneu.2012.02.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Revised: 02/23/2012] [Accepted: 02/24/2012] [Indexed: 02/02/2023]
Abstract
Injection into the nucleus tractus solitarii (NTS) of toxins that target substance P (SP) receptors ablates neurons that express neurokinin-1 (NK1) receptors, attenuates baroreflexes, and results in increased lability of arterial pressure. We and others have shown that the toxin leads to loss of neurons containing SP receptors and loss of GABAergic neurons in the NTS; but given that neither type neuron is thought to be integral to baroreflex transmission in NTS, mechanisms responsible for the cardiovascular changes remained unclear. Because NK1 receptors colocalize with N-methyl-d-aspartate (NMDA) receptors and alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors in NTS and because glutamate transmission may be integral to baroreflex transmission in the NTS we hypothesized that the toxic lesions may interrupt mechanisms for glutamate transmission. Interruption of those mechanisms could be responsible for the cardiovascular effects. We tested the hypothesis by performing fluorescent immunohistochemistry, confocal microscopy and image analysis after injecting stabilized SP-SAP (SSP-SAP) unilaterally into the NTS. We assessed changes in immunoreactivity (IR) of NMDA receptor subunit 1 (NMDAR1), AMPA receptor subunit 2 (GluR2), and 3 types of vesicular glutamate transporters (VGluT) as well as IR of gamma-aminobutyric acid receptors type b (GABAb), neuronal nitric oxide synthase (nNOS), tyrosine hydroxylase (TH), and protein gene product 9.5 (PGP 9.5), a neuronal marker, in the NTS. When compared to that of the same section of the un-injected NTS, IR decreased significantly in the injected side for NMDAR1 (p<0.01), GluR2 (p<0.01), VGluT3 (p<0.01), GABAb (p<0.001), and PGP9.5 (p<0.001). In contrast, IR for VGluT1 (p<0.001), VGluT2 (p<0.001), nNOS (p<0.001), and TH (p<0.001) increased significantly. We conclude that pathologic effects following ablation of neurons with NK1 receptors in NTS may result from interruption of neurotransmission through other neurochemical systems associated with NK1 receptors-containing neurons.
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Affiliation(s)
- Li-Hsien Lin
- Department of Neurology, University of Iowa, Iowa City, IA 52242, USA
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Kusnoor SV, Bubser M, Deutch AY. The effects of nigrostriatal dopamine depletion on the thalamic parafascicular nucleus. Brain Res 2012; 1446:46-55. [PMID: 22353754 DOI: 10.1016/j.brainres.2012.01.040] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2011] [Revised: 12/22/2011] [Accepted: 01/18/2012] [Indexed: 10/14/2022]
Abstract
Neuronal loss in Parkinson's disease (PD) is seen in a number of brain regions in addition to the substantia nigra (SN). Among these is the thalamic parafascicular nucleus (PF), which sends glutamatergic projections to the striatum and receives GABAergic inputs from the SN. Recent data suggest that lesions of nigrostriatal dopamine axons cause a loss of PF neurons, which has been interpreted to suggest that the PF cell loss seen in PD is secondary to dopamine denervation. However, the extent of a PF dopamine innervation in the rat is unclear, and it is possible that PF cell loss in parkinsonism is independent of nigrostriatal dopamine degeneration. We characterized the dopamine innervation of the PF in the rat and determined if 6-hydroxydopamine SN lesions cause PF neuron degeneration. Dual-label immunohistochemistry revealed that almost all tyrosine hydroxylase-immunoreactive (TH-ir) axons in the PF also expressed dopamine-beta-hydroxylase and were therefore noradrenergic or adrenergic. Moreover, an antibody directed against dopamine revealed only very rare PF dopaminergic axons. Retrograde-tract tracing-immunohistochemistry did not uncover an innervation of the PF from midbrain dopamine neurons. Nigrostriatal dopamine neuron lesions did not elicit degeneration of PF cells, as reflected by a lack of FluoroJade C staining. Similarly, neither unilateral 6-OHDA lesions of nigrostriatal axons nor the dorsal noradrenergic bundle decreased the number of PF neurons or the number of PF neurons retrogradely-labeled from the striatum. These data suggest that the loss of thalamostriatal PF neurons in Parkinson's Disease is a primary event rather than secondary to nigrostriatal dopamine degeneration.
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Affiliation(s)
- Sheila V Kusnoor
- Department of Psychiatry, Vanderbilt University Medical Center, Nashville, TN 37212, USA
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Kezunovic N, Hyde J, Simon C, Urbano FJ, Williams DK, Garcia-Rill E. Gamma band activity in the developing parafascicular nucleus. J Neurophysiol 2011; 107:772-84. [PMID: 22090455 DOI: 10.1152/jn.00677.2011] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The parafascicular nucleus (Pf) receives cholinergic input from the pedunculopontine nucleus, part of the reticular activating system involved in waking and rapid eye movement (REM) sleep, and sends projections to the cortex. We tested the hypothesis that Pf neurons fire maximally at gamma band frequency (30-90 Hz), that this mechanism involves high-threshold voltage-dependent P/Q- and N-type calcium channels, and that this activity is enhanced by the cholinergic agonist carbachol (CAR). Patch-clamped 9- to 25-day-old rat Pf neurons (n = 299) manifested a firing frequency plateau at gamma band when maximally activated (31.5 ± 1.5 Hz) and showed gamma oscillations when voltage-clamped at holding potentials above -20 mV, and the frequency of the oscillations increased significantly with age (24.6 ± 3.8 vs. 51.6 ± 4.4 Hz, P < 0.001) but plateaued at gamma frequencies. Cells exposed to CAR showed significantly higher frequencies early in development compared with those without CAR (24.6 ± 3.8 vs. 41.7 ± 4.3 Hz, P < 0.001) but plateaued with age. The P/Q-type calcium channel blocker ω-agatoxin-IVA (ω-Aga) blocked gamma oscillations, whereas the N-type blocker ω-conotoxin-GVIA (ω-CgTx) only partially decreased the power spectrum amplitude of gamma oscillations. The blocking effect of ω-Aga on P/Q-type currents and ω-CgTx on N-type currents was consistent over age. We conclude that P/Q- and N-type calcium channels appear to mediate Pf gamma oscillations during development. We hypothesize that the cholinergic input to the Pf could activate these cells to oscillate at gamma frequency, and perhaps relay these rhythms to cortical areas, thus providing a stable high-frequency state for "nonspecific" thalamocortical processing.
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Affiliation(s)
- Nebojsa Kezunovic
- Center for Translational Neuroscience, Dept. of Neurobiology and Developmental Sciences, Univ. of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
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Galvan A, Smith Y. The primate thalamostriatal systems: Anatomical organization, functional roles and possible involvement in Parkinson's disease. ACTA ACUST UNITED AC 2011; 1:179-189. [PMID: 22773963 DOI: 10.1016/j.baga.2011.09.001] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The striatum receives glutamatergic inputs from two main thalamostriatal systems that originate either from the centre median/parafascicular complex (CM/PF-striatal system) or the rostral intralaminar, midline, associative and relay thalamic nuclei (non-CM/PF-striatal system). These dual thalamostriatal systems display striking differences in their anatomical and, most likely, functional organization. The CM/PF-striatal system is topographically organized, and integrated within functionally segregated basal ganglia-thalamostriatal circuits that process sensorimotor, associative and limbic information. CM/PF neurons are highly responsive to attention-related sensory stimuli, suggesting that the CM/PF-striatal system, through its strong connections with cholinergic interneurons, may play a role in basal ganglia-mediated learning, behavioral switching and reinforcement. In light of evidence for prominent CM/PF neuronal loss in Parkinson's disease, we propose that the significant CM-striatal system degeneration, combined with the severe nigrostriatal dopamine loss in sensorimotor striatal regions, may alter normal automatic actions, and shift the processing of basal ganglia-thalamocortical motor programs towards goal-directed behaviors.
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Affiliation(s)
- Adriana Galvan
- Yerkes National Primate Research Center, 954 Gatewood Road NE, Emory University Atlanta, GA 30329, USA; and Department of Neurology, School of Medicine, Emory University, 101 Woodruff Circle, Atlanta GA 30322 USA
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A half century of experimental neuroanatomical tracing. J Chem Neuroanat 2011; 42:157-83. [PMID: 21782932 DOI: 10.1016/j.jchemneu.2011.07.001] [Citation(s) in RCA: 149] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2011] [Revised: 07/04/2011] [Accepted: 07/04/2011] [Indexed: 01/05/2023]
Abstract
Most of our current understanding of brain function and dysfunction has its firm base in what is so elegantly called the 'anatomical substrate', i.e. the anatomical, histological, and histochemical domains within the large knowledge envelope called 'neuroscience' that further includes physiological, pharmacological, neurochemical, behavioral, genetical and clinical domains. This review focuses mainly on the anatomical domain in neuroscience. To a large degree neuroanatomical tract-tracing methods have paved the way in this domain. Over the past few decades, a great number of neuroanatomical tracers have been added to the technical arsenal to fulfill almost any experimental demand. Despite this sophisticated arsenal, the decision which tracer is best suited for a given tracing experiment still represents a difficult choice. Although this review is obviously not intended to provide the last word in the tract-tracing field, we provide a survey of the available tracing methods including some of their roots. We further summarize our experience with neuroanatomical tracers, in an attempt to provide the novice user with some advice to help this person to select the most appropriate criteria to choose a tracer that best applies to a given experimental design.
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Marin C, Bonastre M, Aguilar E, Jiménez A. The metabotropic glutamate receptor antagonist 2-methyl-6-(phenylethynyl) pyridine decreases striatal VGlut2 expression in association with an attenuation of L-DOPA-induced dyskinesias. Synapse 2011; 65:1080-6. [PMID: 21484883 DOI: 10.1002/syn.20941] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2011] [Accepted: 04/03/2011] [Indexed: 11/06/2022]
Abstract
The striatal glutamatergic hyperactivity is considered critical in the development of levodopa-induced dyskinesias (LID) in Parkinson's disease (PD). Pharmacological antagonism of the metabotropic glutamate receptors (mGluRs), in particular, the subtype mGluR5, can inhibit the expression of dyskinesia in both rodent and nonhuman primate models of PD. However, the exact mechanisms underlying the mGluR5 antagonism effects are not completely known. The vesicular glutamate transporters (VGluts) are localized in the synaptic vesicles of the striatal glutamatergic axonal terminals. The effects of mGluR5 antagonism modulating VGlut1 and VGlut2, as selective markers for the corticostriatal and thalamostriatal pathways, respectively, are still unknown. We investigated the effects of the mGluR5 antagonist, 2-methyl-6-(phenylethynyl) pyridine (MPEP) on the striatal expression of VGlut1 and VGlut2 in levodopa-treated hemiparkinsonian rats. Male Sprague-Dawley rats received a unilateral 6-hydroxydopamine (6-OHDA) administration in the nigrostriatal pathway. Rats were treated with: (a) levodopa (12 mg/kg/day with benserazide 15 mg/kg, ip) + vehicle; (b) MPEP (1.5 mg/kg/day, ip) + vehicle; (c) levodopa + MPEP, or (d) saline for 10 days. Levodopa treatment induced dyskinesias and did not modify the striatal expression of either VGlut1 or VGlut2. The administration of MPEP significantly attenuated LID and decreased the levels of VGlut2, but not the VGlut1, in the striatum ipsilateral to the lesion (P < 0.05). Our results suggest that the effects of MPEP on LID might be mediated by a modulating effect on VGlut 2 expression.
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Affiliation(s)
- C Marin
- Laboratori de Neurologia Experimental, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.
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Wichmann T, DeLong MR, Guridi J, Obeso JA. Milestones in research on the pathophysiology of Parkinson's disease. Mov Disord 2011; 26:1032-41. [PMID: 21626548 PMCID: PMC4272856 DOI: 10.1002/mds.23695] [Citation(s) in RCA: 125] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Progress in our understanding of the mechanisms underlying the cardinal motor abnormalities of Parkinson's disease (PD), in particular akinesia and bradykinesia and their treatment, has been remarkable. Notable accomplishments include insights into the functional organization of the basal ganglia and their place in the motor system as components of a family of parallel cortico-subcortical circuits that subserve motor and nonmotor functions and the development of models of the intrinsic organization of the basal ganglia, including delineation of the so-called direct, indirect, and hyperdirect pathways. Studies in primate models of PD have provided insight into the alterations of neuronal activity that are responsible for the motor features of PD, revealing both altered tonic levels of discharge and significant disturbances of the patterns of discharge throughout the motor circuitry and have led to the formulation of circuit models of PD, providing testable hypotheses for research and stimulating the development of new therapies. Most importantly, the discovery that lesions of the subthalamic nucleus, a key node of the indirect pathway, abolish the cardinal features of PD contributed to the renaissance in the use of surgical approaches to treating patients with PD, including ablation and deep brain stimulation.
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Affiliation(s)
- Thomas Wichmann
- Department of Neurology, School of Medicine, Emory University, Atlanta, Georgia, USA.
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Barroso-Chinea P, Rico AJ, Conte-Perales L, Gómez-Bautista V, Luquin N, Sierra S, Roda E, Lanciego JL. Glutamatergic and cholinergic pedunculopontine neurons innervate the thalamic parafascicular nucleus in rats: changes following experimental parkinsonism. Brain Struct Funct 2011; 216:319-30. [PMID: 21499800 DOI: 10.1007/s00429-011-0317-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2011] [Accepted: 03/31/2011] [Indexed: 12/29/2022]
Abstract
The tegmental pedunculopontine nucleus (PPN) is a basal ganglia-related structure that has recently gained renewed interest as a potential surgical target for the treatment of several aspects of Parkinson's disease. However, the underlying anatomical substrates sustaining the choice of the PPN nucleus as a surgical candidate remain poorly understood. Here, we characterized the chemical phenotypes of different subtypes of PPN efferent neurons innervating the rat parafascicular (PF) nucleus. Emphasis was placed on elucidating the impact of unilateral nigrostriatal denervation on the expression patterns of the mRNA coding the vesicular glutamate transporter type 2 (vGlut2 mRNA). We found a bilateral projection from the PPN nucleus to the PF nucleus arising from cholinergic and glutamatergic efferent neurons, with a small fraction of projection neurons co-expressing both cholinergic and glutamatergic markers. Furthermore, the unilateral nigrostriatal depletion induced a bilateral twofold increase in the expression levels of vGlut2 mRNA within the PPN nucleus. Our results support the view that heterogeneous chemical profiles account for PPN efferent neurons innervating thalamic targets. Moreover, a bilateral enhancement of glutamatergic transmission arising from the PPN nucleus occurs following unilateral dopaminergic denervation, therefore sustaining the well-known hyperactivity of the PF nucleus in parkinsonian-like conditions. In conclusion, our data suggest that the ascending projections from the PPN that reach basal ganglia-related targets could play an important role in the pathophysiology of Parkinson's disease.
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Affiliation(s)
- Pedro Barroso-Chinea
- Neurosciences Division, Center for Applied Medical Research (CIMA and CIBERNED), University of Navarra, Pio XII Ave 55, Edificio CIMA, 31008 Pamplona, Spain
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Vernon AC, Crum WR, Johansson SM, Modo M. Evolution of extra-nigral damage predicts behavioural deficits in a rat proteasome inhibitor model of Parkinson's disease. PLoS One 2011; 6:e17269. [PMID: 21364887 PMCID: PMC3045435 DOI: 10.1371/journal.pone.0017269] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2010] [Accepted: 01/25/2011] [Indexed: 01/18/2023] Open
Abstract
Establishing the neurological basis of behavioural dysfunction is key to provide a better understanding of Parkinson's disease (PD) and facilitate development of effective novel therapies. For this, the relationships between longitudinal structural brain changes associated with motor behaviour were determined in a rat model of PD and validated by post-mortem immunohistochemistry. Rats bearing a nigrostriatal lesion induced by infusion of the proteasome inhibitor lactacystin into the left-medial forebrain bundle and saline-injected controls underwent magnetic resonance imaging (MRI) at baseline (prior to surgery) and 1, 3 and 5 weeks post-surgery with concomitant motor assessments consisting of forelimb grip strength, accelerating rotarod, and apormorphine-induced rotation. Lactacystin-injected rats developed early motor deficits alongside decreased ipsilateral cortical volumes, specifically thinning of the primary motor (M1) and somatosensory cortices and lateral ventricle hypertrophy (as determined by manual segmentation and deformation-based morphometry). Although sustained, motor dysfunction and nigrostriatal damage were maximal by 1 week post-surgery. Additional volume decreases in the ipsilateral ventral midbrain; corpus striatum and thalamus were only evident by week 3 and 5. Whilst cortical MRI volume changes best predicted the degree of motor impairment, post-mortem tyrosine hydroxylase immunoreactivity in the striatum was a better predictor of motor behaviour overall, with the notable exception of performance in the accelerating rotarod, in which, M1 cortical thickness remained the best predictor. These results highlight the importance of identifying extra-nigral regions of damage that impact on behavioural dysfunction from damage to the nigrostriatal system.
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Affiliation(s)
- Anthony C. Vernon
- Department of Neuroscience, Centre for the Cellular Basis of Behaviour, Institute of Psychiatry, Kings College London, London, United Kingdom
| | - William R. Crum
- Department of Neuroimaging, Institute of Psychiatry, Kings College London, London, United Kingdom
| | - Saga M. Johansson
- Department of Neuroscience, Centre for the Cellular Basis of Behaviour, Institute of Psychiatry, Kings College London, London, United Kingdom
| | - Michel Modo
- Department of Neuroscience, Centre for the Cellular Basis of Behaviour, Institute of Psychiatry, Kings College London, London, United Kingdom
- * E-mail:
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Jouve L, Salin P, Melon C, Goff LKL. Deep brain stimulation of the center median-parafascicular complex of the thalamus has efficient anti-parkinsonian action associated with widespread cellular responses in the basal ganglia network in a rat model of Parkinson's disease. J Neurosci 2010; 30:9919-28. [PMID: 20660274 PMCID: PMC6632817 DOI: 10.1523/jneurosci.1404-10.2010] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2010] [Revised: 05/04/2010] [Accepted: 06/11/2010] [Indexed: 11/21/2022] Open
Abstract
The thalamic centromedian-parafascicular (CM/Pf) complex, mainly represented by Pf in rodents, is proposed as an interesting target for the neurosurgical treatment of movement disorders, including Parkinson's disease. In this study, we examined the functional impact of subchronic high-frequency stimulation (HFS) of Pf in the 6-hydroxydopamine-lesioned hemiparkinsonian rat model. Pf-HFS had significant anti-akinetic action, evidenced by alleviation of limb use asymmetry (cylinder test). Whereas this anti-akinetic action was moderate, Pf-HFS totally reversed lateralized neglect (corridor task), suggesting potent action on sensorimotor integration. At the cellular level, Pf-HFS partially reversed the dopamine denervation-induced increase in striatal preproenkephalin A mRNA levels, a marker of the neurons of the indirect pathway, without interfering with the markers of the direct pathway (preprotachykinin and preprodynorphin). Pf-HFS totally reversed the lesion-induced changes in the gene expression of cytochrome oxidase subunit I in the subthalamic nucleus, the globus pallidus, and the substantia nigra pars reticulata, and partially in the entopeduncular nucleus. Unlike HFS of the subthalamic nucleus, Pf-HFS did not induce per se dyskinesias and directly, although partially, alleviated L-3,4-dihydroxyphenylalanine (L-DOPA)-induced forelimb dyskinesia. Conversely, L-DOPA treatment negatively interfered with the anti-parkinsonian effect of Pf-HFS. Altogether, these data show that Pf-DBS, by recruiting a large basal ganglia circuitry, provides moderate to strong anti-parkinsonian benefits that might, however, be affected by L-DOPA. The widespread behavioral and cellular outcomes of Pf-HFS evidenced here demonstrate that CM/Pf is an important node for modulating the pathophysiological functioning of basal ganglia and related disorders.
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Affiliation(s)
- Loréline Jouve
- Developmental Biology Institute of Marseille Luminy, Unité Mixte de Recherche 6216 Centre National de la Recherche Scientifique-Université de la Méditerranée, 13288 Marseille, France
| | - Pascal Salin
- Developmental Biology Institute of Marseille Luminy, Unité Mixte de Recherche 6216 Centre National de la Recherche Scientifique-Université de la Méditerranée, 13288 Marseille, France
| | - Christophe Melon
- Developmental Biology Institute of Marseille Luminy, Unité Mixte de Recherche 6216 Centre National de la Recherche Scientifique-Université de la Méditerranée, 13288 Marseille, France
| | - Lydia Kerkerian-Le Goff
- Developmental Biology Institute of Marseille Luminy, Unité Mixte de Recherche 6216 Centre National de la Recherche Scientifique-Université de la Méditerranée, 13288 Marseille, France
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Dzahini K, Dentresangle C, Le Cavorsin M, Bertrand A, Detraz I, Savasta M, Leviel V. Pre-synaptic glutamate-induced activation of DA release in the striatum after partial nigral lesion. J Neurochem 2010; 113:1459-70. [DOI: 10.1111/j.1471-4159.2010.06682.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Abstract
One of the most marked differences to be identified in Parkinson's disease is the change in activity of thalamic neurons in the motor circuits. Because dopamine replacement therapies largely alleviate these motor circuit abnormalities, it has been assumed that pathology in the basal ganglia is entirely responsible for the aberrant thalamic activity which then permeates the motor circuits. However, there is considerable evidence that pathology in the thalamus itself contributes to the abnormal neural activity characteristic of Parkinson's disease. In a series of studies examining the degree of degeneration in the thalamus, we have observed selective degeneration in the intralaminar thalamic nuclei in patients with levodopa-responsive Parkinson's disease. The nuclei involved are the caudal intralaminar nuclei (the centre-median/parafascicular complex), the parataenial, cucullar and central lateral nuclei. The centre-median/parafascicular complex provides important glutaminergic feedback from the thalamus to the putamen and is a pathway that is greatly enlarged in primates. There is 30-40% loss in this region of the thalamus in idiopathic Parkinson's disease, with non-parvalbumin-containing neurons degenerating the most (70% average loss). Our recent work suggests that the preservation of this pathway may contribute to dystonia in Parkinson's disease. The central lateral and cucullar thalamic nuclei degenerate 30-50%, while the parataenial nucleus sustains a 55% loss of neurons in association with significant alpha-synuclein deposition which correlates with disease duration. Damage to these regions appears to impact on cognition, awareness and perception. These studies suggest that direct thalamic pathology contributes to the symptoms of Parkinson's disease.
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Kusnoor SV, Muly EC, Morgan JI, Deutch AY. Is the loss of thalamostriatal neurons protective in parkinsonism? Parkinsonism Relat Disord 2009; 15 Suppl 3:S162-6. [PMID: 20082981 PMCID: PMC2900831 DOI: 10.1016/s1353-8020(09)70806-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Neuronal loss in Parkinson's disease (PD) is more widespread than originally thought. Among the extrastriatal sites in which significant loss of neurons has been reported is the centremedian-parafascicular (CM-PF) complex of the thalamus, which provides one of the three major afferent sources to the striatum. The functional significance of CM-PF loss in PD is unclear. Interestingly, several recent small trials have suggested that deep brain stimulation of the CM-PF improves motor function in PD. We discuss the possible transsynaptic determination of CM-PF loss secondary to nigrostriatal dopamine degeneration, and suggest that expression of the glycoprotein cerebellin1 (Cbln1) in CM-PF neurons may play an important role in striatal synaptic remodeling in parkinsonism.
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Affiliation(s)
- Sheila V. Kusnoor
- Program in Neuroscience and Departments of Psychiatry and Pharmacology Vanderbilt University Medical Center Nashville, TN 37212 USA
| | - E. Chris Muly
- Department of Psychiatry and Behavioral Sciences Emory University School of Medicine Atlanta, GA 30322 USA
| | - James I. Morgan
- Department of Developmental Neurobiology St. Jude Children's Research Hospital Memphis, TN 38105 USA
| | - Ariel Y. Deutch
- Program in Neuroscience and Departments of Psychiatry and Pharmacology Vanderbilt University Medical Center Nashville, TN 37212 USA
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Goff LKL, Jouve L, Melon C, Salin P. Rationale for targeting the thalamic centre-median parafascicular complex in the surgical treatment of Parkinson's disease. Parkinsonism Relat Disord 2009; 15 Suppl 3:S167-70. [DOI: 10.1016/s1353-8020(09)70807-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Truong L, Brooks D, Amaral F, Henderson JM, Halliday GM. Relative preservation of thalamic centromedian nucleus in parkinsonian patients with dystonia. Mov Disord 2009; 24:2128-35. [DOI: 10.1002/mds.22747] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Gubellini P, Salin P, Kerkerian-Le Goff L, Baunez C. Deep brain stimulation in neurological diseases and experimental models: From molecule to complex behavior. Prog Neurobiol 2009; 89:79-123. [DOI: 10.1016/j.pneurobio.2009.06.003] [Citation(s) in RCA: 119] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2008] [Revised: 04/28/2009] [Accepted: 06/18/2009] [Indexed: 11/30/2022]
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Sedaghat K, Finkelstein DI, Gundlach AL. Effect of unilateral lesion of the nigrostriatal dopamine pathway on survival and neurochemistry of parafascicular nucleus neurons in the rat — Evaluation of time-course and LGR8 expression. Brain Res 2009; 1271:83-94. [DOI: 10.1016/j.brainres.2009.03.026] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2008] [Revised: 03/10/2009] [Accepted: 03/11/2009] [Indexed: 11/30/2022]
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Parr-Brownlie LC, Poloskey SL, Bergstrom DA, Walters JR. Parafascicular thalamic nucleus activity in a rat model of Parkinson's disease. Exp Neurol 2009; 217:269-81. [PMID: 19268664 DOI: 10.1016/j.expneurol.2009.02.010] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2008] [Revised: 01/26/2009] [Accepted: 02/24/2009] [Indexed: 10/21/2022]
Abstract
Parkinson's disease is associated with increased oscillatory firing patterns in basal ganglia output, which are thought to disrupt thalamocortical activity. However, it is unclear how specific thalamic nuclei are affected by these changes in basal ganglia activity. The thalamic parafascicular nucleus (PFN) receives input from basal ganglia output nuclei and directly projects to the subthalamic nucleus (STN), striatum and cortex; thus basal ganglia-mediated changes on PFN activity may further impact basal ganglia and cortical functions. To investigate the impact of increased oscillatory activity in basal ganglia output on PFN activity after dopamine cell lesion, PFN single-unit and local field potential activities were recorded in neurologically intact (control) rats and in both non-lesioned and dopamine lesioned hemispheres of unilateral 6-hydroxydopamine lesioned rats anesthetized with urethane. Firing rates were unchanged 1-2 weeks after lesion; however, significantly fewer spontaneously active PFN neurons were evident. Firing pattern assessments after lesion showed that a larger proportion of PFN spike trains had 0.3-2.5 Hz oscillatory activity and significantly fewer spike trains exhibited low threshold calcium spike (LTS) bursts. In paired recordings, more PFN-STN spike oscillations were significantly correlated, but as these oscillations were in-phase, results are inconsistent with feedforward control of PFN activity by inhibitory oscillatory basal ganglia output. Furthermore, the decreased incidence of LTS bursts is incompatible with inhibitory basal ganglia output inducing rebound bursting in PFN after dopamine lesion. Together, results show that robust oscillatory activity observed in basal ganglia output nuclei after dopamine cell lesion does not directly drive changes in PFN oscillatory activity.
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Affiliation(s)
- Louise C Parr-Brownlie
- Neurophysiological Pharmacology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, 35 Convent Drive, Building 35 Room 1C 905, Bethesda, MD 20892-3702 USA.
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