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Bjerke IE, Yates SC, Carey H, Bjaalie JG, Leergaard TB. Scaling up cell-counting efforts in neuroscience through semi-automated methods. iScience 2023; 26:107562. [PMID: 37636060 PMCID: PMC10457595 DOI: 10.1016/j.isci.2023.107562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/29/2023] Open
Abstract
Quantifying how the cellular composition of brain regions vary across development, aging, sex, and disease, is crucial in experimental neuroscience, and the accuracy of different counting methods is continuously debated. Due to the tedious nature of most counting procedures, studies are often restricted to one or a few brain regions. Recently, there have been considerable methodological advances in combining semi-automated feature extraction with brain atlases for cell quantification. Such methods hold great promise for scaling up cell-counting efforts. However, little focus has been paid to how these methods should be implemented and reported to support reproducibility. Here, we provide an overview of practices for conducting and reporting cell counting in mouse and rat brains, showing that critical details for interpretation are typically lacking. We go on to discuss how novel methods may increase efficiency and reproducibility of cell counting studies. Lastly, we provide practical recommendations for researchers planning cell counting.
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Affiliation(s)
- Ingvild Elise Bjerke
- Neural Systems Laboratory, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Sharon Christine Yates
- Neural Systems Laboratory, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Harry Carey
- Neural Systems Laboratory, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Jan Gunnar Bjaalie
- Neural Systems Laboratory, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Trygve Brauns Leergaard
- Neural Systems Laboratory, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
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2
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Delignat-Lavaud B, Kano J, Ducrot C, Massé I, Mukherjee S, Giguère N, Moquin L, Lévesque C, Burke S, Denis R, Bourque MJ, Tchung A, Rosa-Neto P, Lévesque D, De Beaumont L, Trudeau LÉ. Synaptotagmin-1-dependent phasic axonal dopamine release is dispensable for basic motor behaviors in mice. Nat Commun 2023; 14:4120. [PMID: 37433762 PMCID: PMC10336101 DOI: 10.1038/s41467-023-39805-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Accepted: 06/27/2023] [Indexed: 07/13/2023] Open
Abstract
In Parkinson's disease (PD), motor dysfunctions only become apparent after extensive loss of DA innervation. This resilience has been hypothesized to be due to the ability of many motor behaviors to be sustained through a diffuse basal tone of DA; but experimental evidence for this is limited. Here we show that conditional deletion of the calcium sensor synaptotagmin-1 (Syt1) in DA neurons (Syt1 cKODA mice) abrogates most activity-dependent axonal DA release in the striatum and mesencephalon, leaving somatodendritic (STD) DA release intact. Strikingly, Syt1 cKODA mice showed intact performance in multiple unconditioned DA-dependent motor tasks and even in a task evaluating conditioned motivation for food. Considering that basal extracellular DA levels in the striatum were unchanged, our findings suggest that activity-dependent DA release is dispensable for such tasks and that they can be sustained by a basal tone of extracellular DA. Taken together, our findings reveal the striking resilience of DA-dependent motor functions in the context of a near-abolition of phasic DA release, shedding new light on why extensive loss of DA innervation is required to reveal motor dysfunctions in PD.
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Affiliation(s)
- Benoît Delignat-Lavaud
- Department of Pharmacology and Physiology, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
- Department of Neurosciences, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
- SNC and CIRCA Research Groups, Université de Montréal, Montréal, QC, Canada
| | - Jana Kano
- Department of Pharmacology and Physiology, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
- Department of Neurosciences, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
- SNC and CIRCA Research Groups, Université de Montréal, Montréal, QC, Canada
| | - Charles Ducrot
- Department of Pharmacology and Physiology, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
- Department of Neurosciences, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
- SNC and CIRCA Research Groups, Université de Montréal, Montréal, QC, Canada
| | - Ian Massé
- Hôpital du Sacré-Cœur-de-Montréal, CIUSSS NIM, Université de Montréal, Montreal, QC, Canada
| | - Sriparna Mukherjee
- Department of Pharmacology and Physiology, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
- Department of Neurosciences, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
- SNC and CIRCA Research Groups, Université de Montréal, Montréal, QC, Canada
- Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD, 20815, USA
| | - Nicolas Giguère
- Department of Pharmacology and Physiology, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
- Department of Neurosciences, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
- SNC and CIRCA Research Groups, Université de Montréal, Montréal, QC, Canada
| | - Luc Moquin
- Centre intégré universitaire de santé et de services sociaux (CIUSSS) de l'Ouest-de-l'Île-de-Montréal; Department of Neurology and Neurosurgery, Psychiatry and Pharmacology and Therapeutics, McGill University, Montreal, QC, Canada
| | | | - Samuel Burke
- Department of Pharmacology and Physiology, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
- Department of Neurosciences, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
- SNC and CIRCA Research Groups, Université de Montréal, Montréal, QC, Canada
| | - Raphaëlle Denis
- Department of Pharmacology and Physiology, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
- Department of Neurosciences, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
- SNC and CIRCA Research Groups, Université de Montréal, Montréal, QC, Canada
| | - Marie-Josée Bourque
- Department of Pharmacology and Physiology, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
- Department of Neurosciences, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
- SNC and CIRCA Research Groups, Université de Montréal, Montréal, QC, Canada
- Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD, 20815, USA
| | - Alex Tchung
- Department of Pharmacology and Physiology, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
- Department of Neurosciences, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
- SNC and CIRCA Research Groups, Université de Montréal, Montréal, QC, Canada
| | - Pedro Rosa-Neto
- Centre intégré universitaire de santé et de services sociaux (CIUSSS) de l'Ouest-de-l'Île-de-Montréal; Department of Neurology and Neurosurgery, Psychiatry and Pharmacology and Therapeutics, McGill University, Montreal, QC, Canada
| | - Daniel Lévesque
- Faculty of Pharmacy, Université de Montréal, Montreal, QC, Canada
| | - Louis De Beaumont
- Hôpital du Sacré-Cœur-de-Montréal, CIUSSS NIM, Université de Montréal, Montreal, QC, Canada
| | - Louis-Éric Trudeau
- Department of Pharmacology and Physiology, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada.
- Department of Neurosciences, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada.
- SNC and CIRCA Research Groups, Université de Montréal, Montréal, QC, Canada.
- Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD, 20815, USA.
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3
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Sun X, Li X, Zhang L, Zhang Y, Qi X, Wang S, Qin C. Longitudinal assessment of motor function following the unilateral intrastriatal 6-hydroxydopamine lesion model in mice. Front Behav Neurosci 2022; 16:982218. [PMID: 36505729 PMCID: PMC9730519 DOI: 10.3389/fnbeh.2022.982218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 11/04/2022] [Indexed: 11/27/2022] Open
Abstract
Introduction Despite the widespread use of the unilateral striatal 6-hydroxydopamine (6-OHDA) lesion model in mice in recent years, the stability of behavioral deficits in the 6-OHDA striatal mouse model over time is not yet clear, raising concerns about using this model to evaluate a compound's long-term therapeutic effects. Materials and methods In the current study, mice were tested at regular intervals in the cylinder test and gait analysis beginning 3 days after 6-OHDA injection of 4 and 8 μg and lasting until 56 days post-lesion. Apomorphine-induced rotational test and rotarod test were also performed on Day 23 and 43 post-lesion, respectively. Immunohistochemistry for dopaminergic neurons stained by tyrosine hydroxylase (TH) was also performed. Results Our results showed that both the 4 and 8 μg 6-OHDA lesion groups exhibited forelimb use asymmetry with a preference for the ipsilateral (injection) side on Day 3 and until Day 21 post-lesion, but did not show forelimb asymmetry on Day 28 to 56 post-lesion. The 8 μg 6-OHDA lesion group still exhibited forelimb asymmetry on Day 28 and 42 post-lesion, but not on Day 56. The gait analysis showed that the contralateral front and hind step cycles increased from Day 3 to 42 post-lesion and recovered on Day 56 post-lesion. In addition, our results displayed a dose-dependent reduction in TH+ cells and TH+ fibers, as well as dose-dependent apomorphine-induced rotations. In the rotarod test, the 8 μg 6-OHDA lesion group, but not the 4 μg group, decreased the latency to fall on the rotarod on Day 43 post-lesion. Conclusion In summary, unilateral striatal 6-OHDA injections of 4 and 8 μg induced spontaneous motor impairment in mice, which partially recovered starting on Day 28 post-lesion. Forced motor deficits were observed in the 8 g 6-OHDA lesion group, which remained stable on Day 43 post-lesion. In addition, the rotarod test and apomorphine-induced rotational test can distinguish between lesions of different extents and are useful tools for the assessment of functional recovery in studies screening novel potential therapies.
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Affiliation(s)
- Xiuping Sun
- National Health Commission Key Laboratory of Human Disease Comparative Medicine, Beijing Engineering Research Center for Experimental Animal Models of Human Critical Diseases, National Center of Technology Innovation for Animal Model, Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences (CAMS) & Peking Union Medical College (PUMC), Beijing, China
| | - Xianglei Li
- National Health Commission Key Laboratory of Human Disease Comparative Medicine, Beijing Engineering Research Center for Experimental Animal Models of Human Critical Diseases, National Center of Technology Innovation for Animal Model, Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences (CAMS) & Peking Union Medical College (PUMC), Beijing, China
| | - Ling Zhang
- National Health Commission Key Laboratory of Human Disease Comparative Medicine, Beijing Engineering Research Center for Experimental Animal Models of Human Critical Diseases, National Center of Technology Innovation for Animal Model, Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences (CAMS) & Peking Union Medical College (PUMC), Beijing, China
| | - Yu Zhang
- National Health Commission Key Laboratory of Human Disease Comparative Medicine, Beijing Engineering Research Center for Experimental Animal Models of Human Critical Diseases, National Center of Technology Innovation for Animal Model, Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences (CAMS) & Peking Union Medical College (PUMC), Beijing, China
| | - Xiaolong Qi
- National Health Commission Key Laboratory of Human Disease Comparative Medicine, Beijing Engineering Research Center for Experimental Animal Models of Human Critical Diseases, National Center of Technology Innovation for Animal Model, Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences (CAMS) & Peking Union Medical College (PUMC), Beijing, China
| | - Siyuan Wang
- National Health Commission Key Laboratory of Human Disease Comparative Medicine, Beijing Engineering Research Center for Experimental Animal Models of Human Critical Diseases, National Center of Technology Innovation for Animal Model, Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences (CAMS) & Peking Union Medical College (PUMC), Beijing, China
| | - Chuan Qin
- National Health Commission Key Laboratory of Human Disease Comparative Medicine, Beijing Engineering Research Center for Experimental Animal Models of Human Critical Diseases, National Center of Technology Innovation for Animal Model, Institute of Laboratory Animal Sciences, Chinese Academy of Medical Sciences (CAMS) & Peking Union Medical College (PUMC), Beijing, China,Changping National Laboratory (CPNL), Beijing, China,*Correspondence: Chuan Qin,
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4
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Peters KZ, Naneix F. The role of dopamine and endocannabinoid systems in prefrontal cortex development: Adolescence as a critical period. Front Neural Circuits 2022; 16:939235. [PMID: 36389180 PMCID: PMC9663658 DOI: 10.3389/fncir.2022.939235] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2022] [Accepted: 10/14/2022] [Indexed: 01/07/2023] Open
Abstract
The prefrontal cortex plays a central role in the control of complex cognitive processes including action control and decision making. It also shows a specific pattern of delayed maturation related to unique behavioral changes during adolescence and allows the development of adult cognitive processes. The adolescent brain is extremely plastic and critically vulnerable to external insults. Related to this vulnerability, adolescence is also associated with the emergence of numerous neuropsychiatric disorders involving alterations of prefrontal functions. Within prefrontal microcircuits, the dopamine and the endocannabinoid systems have widespread effects on adolescent-specific ontogenetic processes. In this review, we highlight recent advances in our understanding of the maturation of the dopamine system and the endocannabinoid system in the prefrontal cortex during adolescence. We discuss how they interact with GABA and glutamate neurons to modulate prefrontal circuits and how they can be altered by different environmental events leading to long-term neurobiological and behavioral changes at adulthood. Finally, we aim to identify several future research directions to help highlight gaps in our current knowledge on the maturation of these microcircuits.
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Affiliation(s)
- Kate Zara Peters
- Sussex Neuroscience, School of Psychology, University of Sussex, Falmer, United Kingdom
| | - Fabien Naneix
- The Rowett Institute, University of Aberdeen, Aberdeen, United Kingdom,*Correspondence: Fabien Naneix
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5
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Extracellular Matrix Biomimetic Hydrogels, Encapsulated with Stromal Cell-Derived Factor 1, Improve the Composition of Foetal Tissue Grafts in a Rodent Model of Parkinson's Disease. Int J Mol Sci 2022; 23:ijms23094646. [PMID: 35563037 PMCID: PMC9101815 DOI: 10.3390/ijms23094646] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2022] [Revised: 04/12/2022] [Accepted: 04/18/2022] [Indexed: 02/05/2023] Open
Abstract
Clinical studies have provided evidence for dopamine (DA) cell replacement therapy in Parkinson’s Disease. However, grafts derived from foetal tissue or pluripotent stem cells (PSCs) remain heterogeneous, with a high proportion of non-dopaminergic cells, and display subthreshold reinnervation of target tissues, thereby highlighting the need to identify new strategies to improve graft outcomes. In recent work, Stromal Cell-Derived Factor-1 (SDF1), secreted from meninges, has been shown to exert many roles during ventral midbrain DA development and DA-directed differentiation of PSCs. Related, co-implantation of meningeal cells has been shown to improve neural graft outcomes, however, no direct evidence for the role of SDF1 in neural grafting has been shown. Due to the rapid degradation of SDF1 protein, here, we utilised a hydrogel to entrap the protein and sustain its delivery at the transplant site to assess the impact on DA progenitor differentiation, survival and plasticity. Hydrogels were fabricated from self-assembling peptides (SAP), presenting an epitope for laminin, the brain’s main extracellular matrix protein, thereby providing cell adhesive support for the grafts and additional laminin–integrin signalling to influence cell fate. We show that SDF1 functionalised SAP hydrogels resulted in larger grafts, containing more DA neurons, increased A9 DA specification (the subpopulation of DA neurons responsible for motor function) and enhanced innervation. These findings demonstrate the capacity for functionalised, tissue-specific hydrogels to improve the composition of grafts targeted for neural repair.
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6
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McQuade RM, Singleton LM, Wu H, Lee S, Constable R, Di Natale M, Ringuet MT, Berger JP, Kauhausen J, Parish CL, Finkelstein DI, Furness JB, Diwakarla S. The association of enteric neuropathy with gut phenotypes in acute and progressive models of Parkinson's disease. Sci Rep 2021; 11:7934. [PMID: 33846426 PMCID: PMC8041759 DOI: 10.1038/s41598-021-86917-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 03/10/2021] [Indexed: 02/07/2023] Open
Abstract
Parkinson's disease (PD) is associated with neuronal damage in the brain and gut. This work compares changes in the enteric nervous system (ENS) of commonly used mouse models of PD that exhibit central neuropathy and a gut phenotype. Enteric neuropathy was assessed in five mouse models: peripheral injection of MPTP; intracerebral injection of 6-OHDA; oral rotenone; and mice transgenic for A53T variant human α-synuclein with and without rotenone. Changes in the ENS of the colon were quantified using pan-neuronal marker, Hu, and neuronal nitric oxide synthase (nNOS) and were correlated with GI function. MPTP had no effect on the number of Hu+ neurons but was associated with an increase in Hu+ nuclear translocation (P < 0.04). 6-OHDA lesioned mice had significantly fewer Hu+ neurons/ganglion (P < 0.02) and a reduced proportion of nNOS+ neurons in colon (P < 0.001). A53T mice had significantly fewer Hu+ neurons/area (P < 0.001) and exhibited larger soma size (P < 0.03). Treatment with rotenone reduced the number of Hu+ cells/mm2 in WT mice (P < 0.006) and increased the proportion of Hu+ translocated cells in both WT (P < 0.02) and A53T mice (P < 0.04). All PD models exhibited a degree of enteric neuropathy, the extent and type of damage to the ENS, however, was dependent on the model.
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Affiliation(s)
- Rachel M McQuade
- Department of Medicine, Western Health, Melbourne University, Sunshine, VIC, 3021, Australia.
- College of Health and Biomedicine, Victoria University, Sunshine, VIC, 3021, Australia.
- Digestive Physiology and Nutrition Laboratory, The Florey Institute of Neuroscience and Mental Health, Parkville, VIC, 3010, Australia.
| | - Lewis M Singleton
- Digestive Physiology and Nutrition Laboratory, The Florey Institute of Neuroscience and Mental Health, Parkville, VIC, 3010, Australia
| | - Hongyi Wu
- Department of Anatomy and Neuroscience, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Sophie Lee
- Department of Anatomy and Neuroscience, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Remy Constable
- Digestive Physiology and Nutrition Laboratory, The Florey Institute of Neuroscience and Mental Health, Parkville, VIC, 3010, Australia
| | - Madeleine Di Natale
- Digestive Physiology and Nutrition Laboratory, The Florey Institute of Neuroscience and Mental Health, Parkville, VIC, 3010, Australia
| | - Mitchell T Ringuet
- Digestive Physiology and Nutrition Laboratory, The Florey Institute of Neuroscience and Mental Health, Parkville, VIC, 3010, Australia
| | | | - Jessica Kauhausen
- Stem Cells and Neural Development Laboratory, The Florey Institute of Neuroscience and Mental Health, Parkville, VIC, 3010, Australia
| | - Clare L Parish
- Stem Cells and Neural Development Laboratory, The Florey Institute of Neuroscience and Mental Health, Parkville, VIC, 3010, Australia
| | - David I Finkelstein
- Parkinson's Disease Laboratory, The Florey Institute of Neuroscience and Mental Health, Parkville, VIC, 3010, Australia
| | - John B Furness
- Digestive Physiology and Nutrition Laboratory, The Florey Institute of Neuroscience and Mental Health, Parkville, VIC, 3010, Australia
- Department of Anatomy and Neuroscience, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Shanti Diwakarla
- Department of Medicine, Western Health, Melbourne University, Sunshine, VIC, 3021, Australia
- Digestive Physiology and Nutrition Laboratory, The Florey Institute of Neuroscience and Mental Health, Parkville, VIC, 3010, Australia
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Nolan SO, Zachry JE, Johnson AR, Brady LJ, Siciliano CA, Calipari ES. Direct dopamine terminal regulation by local striatal microcircuitry. J Neurochem 2020; 155:475-493. [PMID: 32356315 DOI: 10.1111/jnc.15034] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 04/20/2020] [Accepted: 04/22/2020] [Indexed: 02/06/2023]
Abstract
Regulation of axonal dopamine release by local microcircuitry is at the hub of several biological processes that govern the timing and magnitude of signaling events in reward-related brain regions. An important characteristic of dopamine release from axon terminals in the striatum is that it is rapidly modulated by local regulatory mechanisms. These processes can occur via homosynaptic mechanisms-such as presynaptic dopamine autoreceptors and dopamine transporters - as well heterosynaptic mechanisms such as retrograde signaling from postsynaptic cholinergic and dynorphin systems, among others. Additionally, modulation of dopamine release via diffusible messengers, such as nitric oxide and hydrogen peroxide, allows for various metabolic factors to quickly and efficiently regulate dopamine release and subsequent signaling. Here we review how these mechanisms work in concert to influence the timing and magnitude of striatal dopamine signaling, independent of action potential activity at the level of dopaminergic cell bodies in the midbrain, thereby providing a parallel pathway by which dopamine can be modulated. Understanding the complexities of local regulation of dopamine signaling is required for building comprehensive frameworks of how activity throughout the dopamine system is integrated to drive signaling and control behavior.
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Affiliation(s)
- Suzanne O Nolan
- Department of Pharmacology, Vanderbilt University, Nashville, TN, USA
| | - Jennifer E Zachry
- Department of Pharmacology, Vanderbilt University, Nashville, TN, USA
| | - Amy R Johnson
- Department of Pharmacology, Vanderbilt University, Nashville, TN, USA
| | - Lillian J Brady
- Department of Pharmacology, Vanderbilt University, Nashville, TN, USA
| | - Cody A Siciliano
- Department of Pharmacology, Vanderbilt University, Nashville, TN, USA.,Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, USA.,Vanderbilt Center for Addiction Research, Vanderbilt University, Nashville, TN TN, USA
| | - Erin S Calipari
- Department of Pharmacology, Vanderbilt University, Nashville, TN, USA.,Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, USA.,Vanderbilt Center for Addiction Research, Vanderbilt University, Nashville, TN TN, USA.,Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, USA.,Department of Psychiatry and Behavioral Sciences, Vanderbilt University, Nashville, TN, USA
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8
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Pelzer EA, Melzer C, Schönberger A, Hess M, Timmermann L, Eggers C, Tittgemeyer M. Axonal degeneration in Parkinson's disease - Basal ganglia circuitry and D2 receptor availability. Neuroimage Clin 2019; 23:101906. [PMID: 31254937 PMCID: PMC6603438 DOI: 10.1016/j.nicl.2019.101906] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 06/03/2019] [Accepted: 06/17/2019] [Indexed: 10/27/2022]
Abstract
Basal ganglia (BG) circuitry plays a crucial role in the control of movement. Degeneration of its pathways and imbalance of dopaminergic signalling goes along with movement disorders such as Parkinson's disease. In this study, we explore the interaction of degeneration in two BG pathways (the nigro-striatal and dentato-pallidal pathway) with D2 receptor signalling to elucidate an association to motor impairment and medication response. Included in the study were 24 parkinsonian patients [male, 62 years (± 9.3 SD)] compared to 24 healthy controls [male, 63 years (± 10.2 SD)]; each participant passed through three phases of the study (i) acquisition of metadata/clinical testing, (ii) genotyping and (iii) anatomical/diffusion MRI. We report a decline in nigro-striatal (p < .003) and dentato-pallidal (p < .0001) connectivity in the patients compared to controls, which is associated with increasing motor impairment (relating to nigro-striatal, r = -0.48; p < .001 and dentato-pallidal connectivity, r = -0.36; p = .035). Given, that variations of the ANKK1 Taq1 (rs 1,800,497) allele alters dopamine D2-dependent responses, all participants were genotyped respectively. By grouping patients (and controls) according to their ANKK1 genotype, we demonstrate a link between D2 receptor signalling and decline in connectivity in both investigated pathways for the A1- variant (nigro-striatal pathway: r = -0.53; p = .012, dentato-pallidal pathway: r = -0.62; p = .0012). In patients with the A1+ variant, we only found increased brain connectivity in the dentato-pallidal pathway (r = 0.71; p = .001) correlating with increasing motor impairment, suggesting a potentially compensatory function of the cerebellum. Related to medication response carriers of the A1+ variant had a better drug effect associated with stronger brain connectivity in the nigro-striatal pathway (r = 0.54; p < .02); the A1- group had a good medication response although nigro-striatal connectivity was diminished (r = -0.38; p < .05); these results underscore differences in receptor availability between both groups in the nigro-striatal pathway. No effect onto medication response was found in the dentato-pallidal pathway (p > .05). Interplay between basal ganglia connectivity and D2 receptor availability influence the clinical presentation and medication response of parkinsonian patients. Furthermore, while current models of basal-ganglia function emphasize that balanced activity in the direct and indirect pathways is required for normal movement, our data highlight a role of the cerebellum in compensating for physiological imbalances in this respect.
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Affiliation(s)
- Esther Annegret Pelzer
- Max-Planck-Institute for Metabolism Research Cologne, Germany, Gleueler Str. 50, 50931 Cologne, Germany.
| | - Corina Melzer
- Max-Planck-Institute for Metabolism Research Cologne, Germany, Gleueler Str. 50, 50931 Cologne, Germany
| | - Anna Schönberger
- Department of Neurology, University Hospital Cologne, Kerpener Str. 62, 50937 Cologne, Germany
| | - Martin Hess
- Max-Planck-Institute for Metabolism Research Cologne, Germany, Gleueler Str. 50, 50931 Cologne, Germany
| | - Lars Timmermann
- Department of Neurology, University Hospital Cologne, Kerpener Str. 62, 50937 Cologne, Germany; Department of Neurology, University Hospital Marburg, Baldingerstr., 35039 Marburg, Germany
| | - Carsten Eggers
- Department of Neurology, University Hospital Cologne, Kerpener Str. 62, 50937 Cologne, Germany; Department of Neurology, University Hospital Marburg, Baldingerstr., 35039 Marburg, Germany
| | - Marc Tittgemeyer
- Max-Planck-Institute for Metabolism Research Cologne, Germany, Gleueler Str. 50, 50931 Cologne, Germany; Cologne Cluster of Excellence in Cellular Stress and Aging-Associated Disease (CECAD), Joseph-Stelzmann-Str. 26, 50931 Cologne, Germany
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9
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Hsu SPC, Wang DY, Min MY, Fu YS. Long-term challenge of methylphenidate changes the neuronal population and membrane property of dopaminergic neuron in rats. Neurochem Int 2019; 122:187-195. [DOI: 10.1016/j.neuint.2018.11.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 09/28/2018] [Accepted: 11/02/2018] [Indexed: 01/08/2023]
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10
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Strehl A, Galanis C, Radic T, Schwarzacher SW, Deller T, Vlachos A. Dopamine Modulates Homeostatic Excitatory Synaptic Plasticity of Immature Dentate Granule Cells in Entorhino-Hippocampal Slice Cultures. Front Mol Neurosci 2018; 11:303. [PMID: 30214394 PMCID: PMC6125303 DOI: 10.3389/fnmol.2018.00303] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Accepted: 08/09/2018] [Indexed: 01/27/2023] Open
Abstract
Homeostatic plasticity mechanisms maintain neurons in a stable state. To what extent these mechanisms are relevant during the structural and functional maturation of neural tissue is poorly understood. To reveal developmental changes of a major homeostatic plasticity mechanism, i.e., homeostatic excitatory synaptic plasticity, we analyzed 1-week- and 4-week-old entorhino-hippocampal slice cultures and investigated the ability of immature and mature dentate granule cells (GCs) to express this form of plasticity. Our experiments demonstrate that immature GCs are capable of adjusting their excitatory synaptic strength in a compensatory manner at early postnatal stages, i.e., in 1-week-old preparations, as is the case for mature GCs. This ability of immature dentate GCs is absent in 4-week-old slice cultures. Further investigations into the signaling pathways reveal an important role of dopamine (DA), which prevents homeostatic synaptic up-scaling of immature GCs in young cultures, whereas it does not affect immature and mature GCs in 4-week-old preparations. Together, these results disclose the ability of immature GCs to express homeostatic synaptic plasticity during early postnatal development. They hint toward a novel role of dopaminergic signaling, which may gate activity-dependent changes of newly born neurons by blocking homeostasis.
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Affiliation(s)
- Andreas Strehl
- Neuroscience Center, Institute of Clinical Neuroanatomy, Goethe-University Frankfurt, Frankfurt, Germany
| | - Christos Galanis
- Department of Neuroanatomy, Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Tijana Radic
- Neuroscience Center, Institute of Clinical Neuroanatomy, Goethe-University Frankfurt, Frankfurt, Germany
| | | | - Thomas Deller
- Neuroscience Center, Institute of Clinical Neuroanatomy, Goethe-University Frankfurt, Frankfurt, Germany
| | - Andreas Vlachos
- Neuroscience Center, Institute of Clinical Neuroanatomy, Goethe-University Frankfurt, Frankfurt, Germany.,Department of Neuroanatomy, Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
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11
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Somaa FA, Wang TY, Niclis JC, Bruggeman KF, Kauhausen JA, Guo H, McDougall S, Williams RJ, Nisbet DR, Thompson LH, Parish CL. Peptide-Based Scaffolds Support Human Cortical Progenitor Graft Integration to Reduce Atrophy and Promote Functional Repair in a Model of Stroke. Cell Rep 2018; 20:1964-1977. [PMID: 28834757 DOI: 10.1016/j.celrep.2017.07.069] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Revised: 06/07/2017] [Accepted: 07/24/2017] [Indexed: 12/22/2022] Open
Abstract
Stem cell transplants offer significant hope for brain repair following ischemic damage. Pre-clinical work suggests that therapeutic mechanisms may be multi-faceted, incorporating bone-fide circuit reconstruction by transplanted neurons, but also protection/regeneration of host circuitry. Here, we engineered hydrogel scaffolds to form "bio-bridges" within the necrotic lesion cavity, providing physical and trophic support to transplanted human embryonic stem cell-derived cortical progenitors, as well as residual host neurons. Scaffolds were fabricated by the self-assembly of peptides for a laminin-derived epitope (IKVAV), thereby mimicking the brain's major extracellular protein. Following focal ischemia in rats, scaffold-supported cell transplants induced progressive motor improvements over 9 months, compared to cell- or scaffold-only implants. These grafts were larger, exhibited greater neuronal differentiation, and showed enhanced electrophysiological properties reflective of mature, integrated neurons. Varying graft timing post-injury enabled us to attribute repair to both neuroprotection and circuit replacement. These findings highlight strategies to improve the efficiency of stem cell grafts for brain repair.
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Affiliation(s)
- Fahad A Somaa
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC 3052, Australia
| | - Ting-Yi Wang
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC 3052, Australia
| | - Jonathan C Niclis
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC 3052, Australia
| | - Kiara F Bruggeman
- Laboratory of Advanced Materials, Research School of Engineering, The Australian National University, Canberra, ACT 2601, Australia
| | - Jessica A Kauhausen
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC 3052, Australia
| | - Haoyao Guo
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC 3052, Australia
| | - Stuart McDougall
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC 3052, Australia
| | | | - David R Nisbet
- Laboratory of Advanced Materials, Research School of Engineering, The Australian National University, Canberra, ACT 2601, Australia
| | - Lachlan H Thompson
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC 3052, Australia.
| | - Clare L Parish
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC 3052, Australia.
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12
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Ermine CM, Wright JL, Frausin S, Kauhausen JA, Parish CL, Stanic D, Thompson LH. Modelling the dopamine and noradrenergic cell loss that occurs in Parkinson's disease and the impact on hippocampal neurogenesis. Hippocampus 2018; 28:327-337. [PMID: 29431270 PMCID: PMC5969306 DOI: 10.1002/hipo.22835] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2017] [Revised: 01/07/2018] [Accepted: 02/08/2018] [Indexed: 01/03/2023]
Abstract
Key pathological features of Parkinson's Disease (PD) include the progressive degeneration of midbrain dopaminergic (DA) neurons and hindbrain noradrenergic (NA) neurons. The loss of DA neurons has been extensively studied and is the main cause of motor dysfunction. Importantly, however, there are a range of ‘non‐movement’ related features of PD including cognitive dysfunction, sleep disturbances and mood disorders. The origins for these non‐motor symptoms are less clear, but a possible substrate for cognitive decline may be reduced adult‐hippocampal neurogenesis, which is reported to be impaired in PD. The mechanisms underlying reduced neurogenesis in PD are not well established. Here we tested the hypothesis that NA and DA depletion, as occurs in PD, impairs hippocampal neurogenesis. We used 6‐hydroxydopamine or the immunotoxin dopamine‐β‐hydroxylase‐saporin to selectively lesion DA or NA neurons, respectively, in adult Sprague Dawley rats and assessed hippocampal neurogenesis through phenotyping of cells birth‐dated using 5‐bromo‐2′‐deoxyuridine. The results showed no difference in proliferation or differentiation of newborn cells in the subgranular zone of the dentate gyrus after NA or DA lesions. This suggests that impairment of hippocampal neurogenesis in PD likely results from mechanisms independent of, or in addition to degeneration of DA and NA neurons.
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Affiliation(s)
- Charlotte M Ermine
- Neurodegeneration division, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
| | - Jordan L Wright
- Neurodegeneration division, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
| | - Stefano Frausin
- Neurodegeneration division, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
| | - Jessica A Kauhausen
- Neurodegeneration division, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
| | - Clare L Parish
- Neurodegeneration division, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
| | - Davor Stanic
- Neurodegeneration division, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
| | - Lachlan H Thompson
- Neurodegeneration division, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
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13
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Using minimalist self‐assembling peptides as hierarchical scaffolds to stabilise growth factors and promote stem cell integration in the injured brain. J Tissue Eng Regen Med 2017; 12:e1571-e1579. [DOI: 10.1002/term.2582] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Revised: 09/18/2017] [Accepted: 09/23/2017] [Indexed: 12/16/2022]
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14
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Francardo V, Schmitz Y, Sulzer D, Cenci MA. Neuroprotection and neurorestoration as experimental therapeutics for Parkinson's disease. Exp Neurol 2017; 298:137-147. [PMID: 28988910 DOI: 10.1016/j.expneurol.2017.10.001] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 09/25/2017] [Accepted: 10/03/2017] [Indexed: 12/16/2022]
Abstract
Disease-modifying treatments remain an unmet medical need in Parkinson's disease (PD). Such treatments can be operationally defined as interventions that slow down the clinical evolution to advanced disease milestones. A treatment may achieve this outcome by either inhibiting primary neurodegenerative events ("neuroprotection") or boosting compensatory and regenerative mechanisms in the brain ("neurorestoration"). Here we review experimental paradigms that are currently used to assess the neuroprotective and neurorestorative potential of candidate treatments in animal models of PD. We review some key molecular mediators of neuroprotection and neurorestoration in the nigrostriatal dopamine pathway that are likely to exert beneficial effects on multiple neural systems affected in PD. We further review past and current strategies to therapeutically stimulate these mediators, and discuss the preclinical evidence that exercise training can have neuroprotective and neurorestorative effects. A future translational task will be to combine behavioral and pharmacological interventions to exploit endogenous mechanisms of neuroprotection and neurorestoration for therapeutic purposes. This type of approach is likely to provide benefit to many PD patients, despite the clinical, etiological, and genetic heterogeneity of the disease.
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Affiliation(s)
- Veronica Francardo
- Basal Ganglia Pathophysiology Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden.
| | - Yvonne Schmitz
- Departments Neurology, Psychiatry, Pharmacology, Columbia University Medical Center: Division of Molecular Therapeutics, New York State Psychiatric Institute, New York 10032, NY, USA
| | - David Sulzer
- Departments Neurology, Psychiatry, Pharmacology, Columbia University Medical Center: Division of Molecular Therapeutics, New York State Psychiatric Institute, New York 10032, NY, USA
| | - M Angela Cenci
- Basal Ganglia Pathophysiology Unit, Department of Experimental Medical Science, Lund University, Lund, Sweden.
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15
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Nørbak-Emig H, Pinborg LH, Raghava JM, Svarer C, Baaré WFC, Allerup P, Friberg L, Rostrup E, Glenthøj B, Ebdrup BH. Extrastriatal dopamine D 2/3 receptors and cortical grey matter volumes in antipsychotic-naïve schizophrenia patients before and after initial antipsychotic treatment. World J Biol Psychiatry 2017; 18:539-549. [PMID: 27782768 DOI: 10.1080/15622975.2016.1237042] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
OBJECTIVES Long-term dopamine D2/3 receptor blockade, common to all antipsychotics, may underlie progressive brain volume changes observed in patients with chronic schizophrenia. In the present study, we examined associations between cortical volume changes and extrastriatal dopamine D2/3 receptor binding potentials (BPND) in first-episode schizophrenia patents at baseline and after antipsychotic treatment. METHODS Twenty-two initially antipsychotic-naïve patients underwent magnetic resonance imaging (MRI), [123I]epidepride single-photon emission computerised tomography (SPECT), and psychopathology assessments before and after 3 months of treatment with either risperidone (N = 13) or zuclopenthixol (N = 9). Twenty healthy controls matched on age, gender and parental socioeconomic status underwent baseline MRI and SPECT. RESULTS Neither extrastriatal D2/3 receptor BPND at baseline, nor blockade at follow-up, was related to regional cortical volume changes. In post-hoc analyses excluding three patients with cannabis use we found that higher D2/3 receptor occupancy was significantly associated with an increase in right frontal grey matter volume. CONCLUSIONS The present data do not support an association between extrastriatal D2/3 receptor blockade and extrastriatal grey matter loss in the early phases of schizophrenia. Although inconclusive, our exclusion of patients tested positive for cannabis use speaks to keeping attention to potential confounding factors in imaging studies.
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Affiliation(s)
- Henrik Nørbak-Emig
- a Centre for Neuropsychiatric Schizophrenia Research, CNSR & Centre for Clinical Intervention and Neuropsychiatric Schizophrenia Research, CINS, Mental Health Centre, Glostrup, University of Copenhagen , Denmark.,b Faculty of Health and Medical Sciences, Department of Clinical Medicine , University of Copenhagen , Denmark
| | - Lars H Pinborg
- c Neurobiology Research Unit and Epilepsy Clinic, Rigshospitalet, University of Copenhagen , Denmark
| | - Jayachandra M Raghava
- a Centre for Neuropsychiatric Schizophrenia Research, CNSR & Centre for Clinical Intervention and Neuropsychiatric Schizophrenia Research, CINS, Mental Health Centre, Glostrup, University of Copenhagen , Denmark.,d Functional Imaging Unit, Department of Clinical Physiology and Nuclear Medicine, Rigshospitalet - Glostrup , University of Copenhagen , Denmark
| | - Claus Svarer
- c Neurobiology Research Unit and Epilepsy Clinic, Rigshospitalet, University of Copenhagen , Denmark
| | - William F C Baaré
- e Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Hvidovre Hospital, University of Copenhagen , Denmark
| | - Peter Allerup
- f Institute for Education (DPU), Aarhus University , Denmark
| | - Lars Friberg
- g Department of Clinical Physiology and Nuclear Medicine , Bispebjerg Hospital, University of Copenhagen , Denmark
| | - Egill Rostrup
- d Functional Imaging Unit, Department of Clinical Physiology and Nuclear Medicine, Rigshospitalet - Glostrup , University of Copenhagen , Denmark
| | - Birte Glenthøj
- a Centre for Neuropsychiatric Schizophrenia Research, CNSR & Centre for Clinical Intervention and Neuropsychiatric Schizophrenia Research, CINS, Mental Health Centre, Glostrup, University of Copenhagen , Denmark.,b Faculty of Health and Medical Sciences, Department of Clinical Medicine , University of Copenhagen , Denmark
| | - Bjørn H Ebdrup
- a Centre for Neuropsychiatric Schizophrenia Research, CNSR & Centre for Clinical Intervention and Neuropsychiatric Schizophrenia Research, CINS, Mental Health Centre, Glostrup, University of Copenhagen , Denmark
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16
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Mendes-Oliveira J, Lopes Campos F, Videira RA, Baltazar G. GPER activation is effective in protecting against inflammation-induced nigral dopaminergic loss and motor function impairment. Brain Behav Immun 2017; 64:296-307. [PMID: 28450223 DOI: 10.1016/j.bbi.2017.04.016] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Revised: 04/21/2017] [Accepted: 04/21/2017] [Indexed: 12/29/2022] Open
Abstract
Increasing evidence suggest that excessive inflammatory responses from overactivated microglia play a critical role in Parkinson's disease (PD), contributing to, or exacerbating, nigral dopaminergic (DA) degeneration. Recent results from our group and others demonstrated that selective activation of G protein-coupled estrogen receptor (GPER) with the agonist G1 can protect DA neurons from 1-methyl-4-phenylpyridinium (MPP+) and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) neurotoxins. However, it is not known whether modulation of microglial responses is one of the mechanisms by which G1 exerts its DA neuroprotective effects. We analyzed, in the N9 microglial cell line, the effect of G1 on microglial activation induced by lipopolysaccharide (LPS) exposure. The results revealed that G1 significantly decrease phagocytic activity, expression of inducible nitric oxide synthase (iNOS) and release of nitric oxide (NO) induced by LPS. To determine the relevance of this anti-inflammatory effect to the protection of nigral DA cells, the effect of G1 was analyzed in male mice injected unilaterally in the substantia nigra (SN) with LPS. Although G1 treatment did not decrease LPS-induced increase of ionized calcium binding adaptor molecule 1 (iba-1) positive cells it significantly reduced interleukin-1beta (IL-1β), cluster of differentiation 68 (CD68) and iNOS mRNA levels, and totally inhibited nigral DA cell loss and, as a consequence, protected the motor function. In summary, our findings demonstrated that the G1 agonist is able to modulate microglial responses and to protect DA neurons and motor functions against a lesion induced by an inflammatory insult. Since G1 lacks the feminizing effects associated with agonists of the classical estrogen receptors (ERs), the use of G1 to selectively activate the GPER may be a promising strategy for the development of new therapeutics for the treatment of PD and other neuroinflammatory diseases.
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Affiliation(s)
- Julieta Mendes-Oliveira
- CICS-UBI - Health Sciences Research Centre, University of Beira Interior, Covilhã, Portugal.
| | - Filipa Lopes Campos
- CICS-UBI - Health Sciences Research Centre, University of Beira Interior, Covilhã, Portugal.
| | - Rita Alexandra Videira
- CICS-UBI - Health Sciences Research Centre, University of Beira Interior, Covilhã, Portugal.
| | - Graça Baltazar
- CICS-UBI - Health Sciences Research Centre, University of Beira Interior, Covilhã, Portugal.
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17
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Exercise in an animal model of Parkinson's disease: Motor recovery but not restoration of the nigrostriatal pathway. Neuroscience 2017; 359:224-247. [PMID: 28754312 DOI: 10.1016/j.neuroscience.2017.07.031] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Revised: 07/11/2017] [Accepted: 07/13/2017] [Indexed: 11/23/2022]
Abstract
Many clinical studies have reported on the benefits of exercise therapy in patients with Parkinson's disease (PD). Exercise cannot stop the progression of PD or facilitate the recovery of dopamine (DA) neurons in the substantia nigra pars compacta (SNpc) (Bega et al., 2014). To tease apart this paradox, we utilized a progressive MPTP (1-methyl-4-phenyl-1,2,3,6-tetra-hydropyridine) mouse model in which we initiated 4weeks of treadmill exercise after the completion of toxin administration (i.e., restoration). We found in our MPTP/exercise (MPTP+EX) group several measures of gait function that recovered compared to the MPTP only group. Although there was a small recovery of tyrosine hydroxylase (TH) positive DA neurons in the SNpc and terminals in the striatum, this increase was not statistically significant. These small changes in TH could not explain the improvement of motor function. The MPTP group had a significant 170% increase in the glycosylated/non-glycosylated dopamine transporter (DAT) and a 200% increase in microglial marker, IBA-1, in the striatum. The MPTP+EX group showed a nearly full recovery of these markers back to the vehicle levels. There was an increase in GLT-1 levels in the striatum due to exercise, with no change in striatal BDNF protein expression. Our data suggest that motor recovery was not prompted by any significant restoration of DA neurons or terminals, but rather the recovery of DAT and dampening the inflammatory response. Although exercise does not promote recovery of nigrostriatal DA, it should be used in conjunction with pharmaceutical methods for controlling PD symptoms.
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The novel compound PBT434 prevents iron mediated neurodegeneration and alpha-synuclein toxicity in multiple models of Parkinson's disease. Acta Neuropathol Commun 2017; 5:53. [PMID: 28659169 PMCID: PMC5490188 DOI: 10.1186/s40478-017-0456-2] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 06/14/2017] [Indexed: 12/18/2022] Open
Abstract
Elevated iron in the SNpc may play a key role in Parkinson's disease (PD) neurodegeneration since drug candidates with high iron affinity rescue PD animal models, and one candidate, deferirpone, has shown efficacy recently in a phase two clinical trial. However, strong iron chelators may perturb essential iron metabolism, and it is not yet known whether the damage associated with iron is mediated by a tightly bound (eg ferritin) or lower-affinity, labile, iron pool. Here we report the preclinical characterization of PBT434, a novel quinazolinone compound bearing a moderate affinity metal-binding motif, which is in development for Parkinsonian conditions. In vitro, PBT434 was far less potent than deferiprone or deferoxamine at lowering cellular iron levels, yet was found to inhibit iron-mediated redox activity and iron-mediated aggregation of α-synuclein, a protein that aggregates in the neuropathology. In vivo, PBT434 did not deplete tissue iron stores in normal rodents, yet prevented loss of substantia nigra pars compacta neurons (SNpc), lowered nigral α-synuclein accumulation, and rescued motor performance in mice exposed to the Parkinsonian toxins 6-OHDA and MPTP, and in a transgenic animal model (hA53T α-synuclein) of PD. These improvements were associated with reduced markers of oxidative damage, and increased levels of ferroportin (an iron exporter) and DJ-1. We conclude that compounds designed to target a pool of pathological iron that is not held in high-affinity complexes in the tissue can maintain the survival of SNpc neurons and could be disease-modifying in PD.
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Ibáñez CF, Andressoo JO. Biology of GDNF and its receptors — Relevance for disorders of the central nervous system. Neurobiol Dis 2017; 97:80-89. [DOI: 10.1016/j.nbd.2016.01.021] [Citation(s) in RCA: 137] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Revised: 01/14/2016] [Accepted: 01/25/2016] [Indexed: 01/15/2023] Open
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20
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Lee CT, Bendriem RM, Freed WJ. A new technique for modeling neuronal connectivity using human pluripotent stem cells. Restor Neurol Neurosci 2016; 33:347-56. [PMID: 25835555 PMCID: PMC4702948 DOI: 10.3233/rnn-140488] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Purpose: We describe a technique for independently differentiating neocortical and mesencephalic dopaminergic (mDA) neurons from a single human pluripotent stem cell (hPSC) line, and subsequently allowing the two cell types to interact and form connections. Methods: Dopaminergic and neocortical progenitors were differentiated in separate vessels, then separately seeded into the inner and outer compartments of specialized cell culture vessels designed for in vitro studies of wound healing. Cells were further differentiated using dopamine-specific and neocortex-specific trophic factors, respectively. The barrier was then removed, and differentiation was continued for three weeks in the presence of BDNF. Results: After three weeks of differentiation, neocortical and mDA cell bodies largely remained in the areas into which they had been seeded, and the gap between the mDA and neocortical neuron populations could still be discerned. Abundant tyrosine hydroxylase (TH)-positive projections had extended from the area of the inner chamber to the outer chamber neocortical area. Conclusions: We have developed a hPSC-based system for producing connections between neurons from two brain regions, neocortex and midbrain. Future experiments could employ modifications of this method to examine connections between any two brain regions or neuronal subtypes that can be produced from hPSCs in vitro.
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Affiliation(s)
- Chun-Ting Lee
- Correspondence to:Dr. Chun-Ting Lee, NIDA Intramural Research Program, 333 Cassell Drive, Triad Bldg, Room 3305, Baltimore, MD 21224, USA. Tel.: +1 443 740 2604; Fax: +1 443 740 2123;
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Altarche-Xifro W, di Vicino U, Muñoz-Martin MI, Bortolozzi A, Bové J, Vila M, Cosma MP. Functional Rescue of Dopaminergic Neuron Loss in Parkinson's Disease Mice After Transplantation of Hematopoietic Stem and Progenitor Cells. EBioMedicine 2016; 8:83-95. [PMID: 27428421 PMCID: PMC4919540 DOI: 10.1016/j.ebiom.2016.04.016] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 04/14/2016] [Indexed: 01/24/2023] Open
Abstract
Parkinson's disease is a common neurodegenerative disorder, which is due to the loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc) and for which no definitive cure is currently available. Cellular functions in mouse and human tissues can be restored after fusion of bone marrow (BM)-derived cells with a variety of somatic cells. Here, after transplantation of hematopoietic stem and progenitor cells (HSPCs) in the SNpc of two different mouse models of Parkinson's disease, we significantly ameliorated the dopaminergic neuron loss and function. We show fusion of transplanted HSPCs with neurons and with glial cells in the ventral midbrain of Parkinson's disease mice. Interestingly, the hybrids can undergo reprogramming in vivo and survived up to 4 weeks after transplantation, while acquiring features of mature astroglia. These newly generated astroglia produced Wnt1 and were essential for functional rescue of the dopaminergic neurons. Our data suggest that glial-derived hybrids produced upon fusion of transplanted HSPCs in the SNpc can rescue the Parkinson's disease phenotype via a niche-mediated effect, and can be exploited as an efficient cell-therapy approach. Transplantation of HSPCs into the substantia nigra of PD mice ameliorates dopaminergic neuron loss and function. Hybrids generated after fusion of transplanted HSPCs undergo reprogramming in vivo and acquire features of mature astroglia. Newly generated astroglia produced Wnt1 and can functionally rescue the dopaminergic neuron loss.
A definitive therapy for Parkinson's disease is not available. Here, we transplanted hematopoietic stem and progenitor cells into the substantia nigra of brains of two different mouse models of Parkinson's disease. These transplanted cells fused with neurons and glial cells of the recipient mice. Four weeks after transplantation, the hybrids acquired features of mature astroglia, secreted Wnt1, and functionally ameliorated dopaminergic neuron loss. Current cell therapy approaches are being pursued in the striatum with the aim to increase dopamine levels. Here we show that the loss of dopaminergic neurons can be protected against by direct actions in the substantia nigra.
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Affiliation(s)
- Wassim Altarche-Xifro
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Dr. Aiguader 88, Barcelona 08003, Spain; Universitat Pompeu Fabra (UPF), Dr Aiguader 88, 08003 Barcelona, Spain
| | - Umberto di Vicino
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Dr. Aiguader 88, Barcelona 08003, Spain; Universitat Pompeu Fabra (UPF), Dr Aiguader 88, 08003 Barcelona, Spain
| | - Maria Isabel Muñoz-Martin
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Dr. Aiguader 88, Barcelona 08003, Spain; Universitat Pompeu Fabra (UPF), Dr Aiguader 88, 08003 Barcelona, Spain
| | - Analía Bortolozzi
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS) and Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Barcelona, Spain; Department of Neurochemistry and Neuropharmacology, IIBB-CSIC (Consejo Superior de Investigaciones Científicas), Barcelona, Spain
| | - Jordi Bové
- Neurodegenerative Diseases Research Group, Vall d'Hebron Research Institute and Centre for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED), Barcelona, Spain
| | - Miquel Vila
- Neurodegenerative Diseases Research Group, Vall d'Hebron Research Institute and Centre for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED), Barcelona, Spain; Department of Biochemistry and Molecular Biology, Autonomous University of Barcelona (UAB), Barcelona, Spain; Institució Catalana de Recerca i Estudis Avançats (ICREA), 08010 Barcelona, Spain
| | - Maria Pia Cosma
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Dr. Aiguader 88, Barcelona 08003, Spain; Universitat Pompeu Fabra (UPF), Dr Aiguader 88, 08003 Barcelona, Spain; Institució Catalana de Recerca i Estudis Avançats (ICREA), 08010 Barcelona, Spain.
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22
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Tomas D, Stanic D, Chua HK, White K, Boon WC, Horne M. Restoration of the Dopamine Transporter through Cell Therapy Improves Dyskinesia in a Rat Model of Parkinson's Disease. PLoS One 2016; 11:e0153424. [PMID: 27077649 PMCID: PMC4831749 DOI: 10.1371/journal.pone.0153424] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2015] [Accepted: 03/29/2016] [Indexed: 11/18/2022] Open
Abstract
The dyskinesia of Parkinson's Disease is most likely due to excess levels of dopamine in the striatum. The mechanism may be due to aberrant synthesis but also, a deficiency or absence of the Dopamine Transporter. In this study we have examined the proposition that reinstating Dopamine Transporter expression in the striatum would reduce dyskinesia. We transplanted c17.2 cells that stably expressed the Dopamine Transporter into dyskinetic rats. There was a reduction in dyskinesia in rats that received grafts expressing the Dopamine Transporter. Strategies designed to increase Dopamine Transporter in the striatum may be useful in treating the dyskinesia associated with human Parkinson's Disease.
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Affiliation(s)
- D. Tomas
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Australia, 3010
| | - D. Stanic
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Australia, 3010
| | - H. K. Chua
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Australia, 3010
| | - K. White
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Australia, 3010
| | - W. C. Boon
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Australia, 3010
| | - M. Horne
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Australia, 3010
- Department of Medicine, University of Melbourne, St Vincent’s Hospital, Fitzroy, Victoria, Australia, 3065
- * E-mail:
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Finkelstein DI, Hare DJ, Billings JL, Sedjahtera A, Nurjono M, Arthofer E, George S, Culvenor JG, Bush AI, Adlard PA. Clioquinol Improves Cognitive, Motor Function, and Microanatomy of the Alpha-Synuclein hA53T Transgenic Mice. ACS Chem Neurosci 2016; 7:119-29. [PMID: 26481462 DOI: 10.1021/acschemneuro.5b00253] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The abnormal accumulation of alpha-synuclein (α-syn) has been linked to a number of neurodegenerative disorders, the most noteworthy of which is Parkinson's disease. Alpha-synuclein itself is not toxic and fulfills various physiological roles in the central nervous system. However, specific types of aggregates have been shown to be toxic, and metals have been linked to the assembly of these toxic aggregates. In this paper, we have characterized a transgenic mouse that overexpresses the A53T mutation of human α-syn, specifically assessing cognition, motor performance, and subtle anatomical markers that have all been observed in synucleinopathies in humans. We hypothesized that treatment with the moderate-affinity metal chelator, clioquinol (CQ), would reduce the interaction between metals and α-syn to subsequently improve the phenotype of the A53T animal model. We showed that CQ prevents an iron-synuclein interaction, the formation of urea-soluble α-syn aggregates, α-syn-related substantia nigra pars compacta cell loss, reduction in dendritic spine density of hippocampal and caudate putamen medium spiny neurons, and the decline in motor and cognitive function. In conclusion, our data suggests that CQ is capable of mitigating the pathological metal/α-syn interactions, suggesting that the modulation of metal ions warrants further study as a therapeutic approach for the synucleinopathies.
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Affiliation(s)
- David I. Finkelstein
- The
Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria 3052, Australia
| | - Dominic J. Hare
- The
Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria 3052, Australia
- Elemental
Bio-imaging Facility, University of Technology Sydney, Broadway, New South Wales 2007, Australia
- Senator
Frank R. Lautenberg Environmental Science Laboratory, Icahn School of Medicine at Mount Sinai, New York, New York 10029, United States
| | - Jessica L. Billings
- The
Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria 3052, Australia
| | - Amelia Sedjahtera
- The
Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria 3052, Australia
| | - Milawaty Nurjono
- The
Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria 3052, Australia
| | - Elisa Arthofer
- The
Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria 3052, Australia
- Department
of Physiology and Pharmacology, Karolinska Institut, Stockholm SE-171 77, Sweden
| | - Sonia George
- School
of Medicine, Dentistry and Health Sciences, The University of Melbourne, Parkville, Victoria 3052, Australia
| | - Janetta G. Culvenor
- School
of Medicine, Dentistry and Health Sciences, The University of Melbourne, Parkville, Victoria 3052, Australia
| | - Ashley I. Bush
- The
Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria 3052, Australia
| | - Paul A. Adlard
- The
Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria 3052, Australia
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24
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Functionalized composite scaffolds improve the engraftment of transplanted dopaminergic progenitors in a mouse model of Parkinson's disease. Biomaterials 2016; 74:89-98. [DOI: 10.1016/j.biomaterials.2015.09.039] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Revised: 09/25/2015] [Accepted: 09/26/2015] [Indexed: 12/16/2022]
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25
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Kumar A, Kopra J, Varendi K, Porokuokka LL, Panhelainen A, Kuure S, Marshall P, Karalija N, Härma MA, Vilenius C, Lilleväli K, Tekko T, Mijatovic J, Pulkkinen N, Jakobson M, Jakobson M, Ola R, Palm E, Lindahl M, Strömberg I, Võikar V, Piepponen TP, Saarma M, Andressoo JO. GDNF Overexpression from the Native Locus Reveals its Role in the Nigrostriatal Dopaminergic System Function. PLoS Genet 2015; 11:e1005710. [PMID: 26681446 PMCID: PMC4682981 DOI: 10.1371/journal.pgen.1005710] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2015] [Accepted: 11/06/2015] [Indexed: 12/14/2022] Open
Abstract
Degeneration of nigrostriatal dopaminergic system is the principal lesion in Parkinson’s disease. Because glial cell line-derived neurotrophic factor (GDNF) promotes survival of dopamine neurons in vitro and in vivo, intracranial delivery of GDNF has been attempted for Parkinson’s disease treatment but with variable success. For improving GDNF-based therapies, knowledge on physiological role of endogenous GDNF at the sites of its expression is important. However, due to limitations of existing genetic model systems, such knowledge is scarce. Here, we report that prevention of transcription of Gdnf 3’UTR in Gdnf endogenous locus yields GDNF hypermorphic mice with increased, but spatially unchanged GDNF expression, enabling analysis of postnatal GDNF function. We found that increased level of GDNF in the central nervous system increases the number of adult dopamine neurons in the substantia nigra pars compacta and the number of dopaminergic terminals in the dorsal striatum. At the functional level, GDNF levels increased striatal tissue dopamine levels and augmented striatal dopamine release and re-uptake. In a proteasome inhibitor lactacystin-induced model of Parkinson’s disease GDNF hypermorphic mice were protected from the reduction in striatal dopamine and failure of dopaminergic system function. Importantly, adverse phenotypic effects associated with spatially unregulated GDNF applications were not observed. Enhanced GDNF levels up-regulated striatal dopamine transporter activity by at least five fold resulting in enhanced susceptibility to 6-OHDA, a toxin transported into dopamine neurons by DAT. Further, we report how GDNF levels regulate kidney development and identify microRNAs miR-9, miR-96, miR-133, and miR-146a as negative regulators of GDNF expression via interaction with Gdnf 3’UTR in vitro. Our results reveal the role of GDNF in nigrostriatal dopamine system postnatal development and adult function, and highlight the importance of correct spatial expression of GDNF. Furthermore, our results suggest that 3’UTR targeting may constitute a useful tool in analyzing gene function. Intracranial delivery of GDNF has been attempted for Parkinson’s disease (PD) treatment but with variable success. For improving GDNF-based therapies, knowledge on physiological role of endogenous GDNF at the sites of its expression is important. However, due to limitations of existing genetic model systems, such knowledge is scarce. Here, we utilize an innovative genetic approach by targeting the 3’UTR regulation of Gdnf in mice. Such animals express elevated levels of Gdnf exclusively in natively Gdnf-expressing cells, enabling dissection of endogenous GDNF functions in vivo. We show that endogenous GDNF regulates dopamine system development and function and protects mice in a rodent PD model without side effects associated with ectopic GDNF applications. Further, we report how GDNF levels regulate kidney development and identify microRNAs which control GDNF expression. Our study highlights the importance of correct spatial expression of GDNF and opens a novel approach to study gene function in mice.
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Affiliation(s)
- Anmol Kumar
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Jaakko Kopra
- Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Kärt Varendi
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | | | - Anne Panhelainen
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Satu Kuure
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Pepin Marshall
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Nina Karalija
- Department of Histology and Cell Biology, Umeå University, Umeå, Sweden
| | - Mari-Anne Härma
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Carolina Vilenius
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Kersti Lilleväli
- Department of Physiology, Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia
| | - Triin Tekko
- Department of Physiology, Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia
| | - Jelena Mijatovic
- Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Nita Pulkkinen
- Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Madis Jakobson
- Department of Biochemistry and Developmental Biology, Institute of Biomedicine, University of Helsinki, Helsinki, Finland
| | - Maili Jakobson
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Roxana Ola
- Department of Biochemistry and Developmental Biology, Institute of Biomedicine, University of Helsinki, Helsinki, Finland
| | - Erik Palm
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Maria Lindahl
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Ingrid Strömberg
- Department of Histology and Cell Biology, Umeå University, Umeå, Sweden
| | - Vootele Võikar
- Neuroscience Center and Department of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - T. Petteri Piepponen
- Division of Pharmacology and Pharmacotherapy, Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Mart Saarma
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Jaan-Olle Andressoo
- Institute of Biotechnology, University of Helsinki, Helsinki, Finland
- * E-mail:
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26
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Chondroitinase improves midbrain pathway reconstruction by transplanted dopamine progenitors in Parkinsonian mice. Mol Cell Neurosci 2015; 69:22-9. [DOI: 10.1016/j.mcn.2015.10.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Revised: 10/07/2015] [Accepted: 10/09/2015] [Indexed: 01/15/2023] Open
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27
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Boix J, Padel T, Paul G. A partial lesion model of Parkinson's disease in mice – Characterization of a 6-OHDA-induced medial forebrain bundle lesion. Behav Brain Res 2015; 284:196-206. [DOI: 10.1016/j.bbr.2015.01.053] [Citation(s) in RCA: 89] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2014] [Revised: 01/17/2015] [Accepted: 01/21/2015] [Indexed: 12/31/2022]
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28
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Homeostatic regulation of excitatory synapses on striatal medium spiny neurons expressing the D2 dopamine receptor. Brain Struct Funct 2015; 221:2093-107. [PMID: 25782435 DOI: 10.1007/s00429-015-1029-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Accepted: 03/06/2015] [Indexed: 10/23/2022]
Abstract
Striatal medium spiny neurons (MSNs) are contacted by glutamatergic axon terminals originating from cortex, thalamus and other regions. The striatum is also innervated by dopaminergic (DAergic) terminals, some of which release glutamate as a co-transmitter. Despite evidence for functional DA release at birth in the striatum, the role of DA in the establishment of striatal circuitry is unclear. In light of recent work suggesting activity-dependent homeostatic regulation of glutamatergic terminals on MSNs expressing the D2 DA receptor (D2-MSNs), we used primary co-cultures to test the hypothesis that stimulation of DA and glutamate receptors regulates the homeostasis of glutamatergic synapses on MSNs. Co-culture of D2-MSNs with mesencephalic DA neurons or with cortical neurons produced an increase in spines and functional glutamate synapses expressing VGLUT2 or VGLUT1, respectively. The density of VGLUT2-positive terminals was reduced by the conditional knockout of this gene from DA neurons. In the presence of both mesencephalic and cortical neurons, the density of synapses reached the same total, compatible with the possibility of a homeostatic mechanism capping excitatory synaptic density. Blockade of D2 receptors increased the density of cortical and mesencephalic glutamatergic terminals, without changing MSN spine density or mEPSC frequency. Combined blockade of AMPA and NMDA glutamate receptors increased the density of cortical terminals and decreased that of mesencephalic VGLUT2-positive terminals, with no net change in total excitatory terminal density or in mEPSC frequency. These results suggest that DA and glutamate signaling regulate excitatory inputs to striatal D2-MSNs at both the pre- and postsynaptic level, under the influence of a homeostatic mechanism controlling functional output of the circuit.
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29
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Somaa FA, Bye CR, Thompson LH, Parish CL. Meningeal cells influence midbrain development and the engraftment of dopamine progenitors in Parkinsonian mice. Exp Neurol 2015; 267:30-41. [PMID: 25708989 DOI: 10.1016/j.expneurol.2015.02.017] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Revised: 01/30/2015] [Accepted: 02/09/2015] [Indexed: 01/09/2023]
Abstract
Dopaminergic neuroblasts, isolated from ventral midbrain fetal tissue, have been shown to structurally and functionally integrate, and alleviate Parkinsonian symptoms following transplantation. The use of donor tissue isolated at an age younger than conventionally employed can result in larger grafts - a consequence of improved cell survival and neuroblast proliferation at the time of implantation. However studies have paid little attention to removal of the meninges from younger tissue, due to its age-dependent tight attachment to the underlying brain. Beyond the protection of the central nervous system, the meninges act as a signaling center, secreting a variety of trophins to influence neural development and additionally impact on neural repair. However it remains to be elucidated what influence these cells have on ventral midbrain development and grafted dopaminergic neuroblasts. Here we examined the temporal role of meningeal cells in graft integration in Parkinsonian mice and, using in vitro approaches, identified the mechanisms underlying the roles of meningeal cells in midbrain development. We demonstrate that young (embryonic day 10), but not older (E12), meningeal cells promote dopaminergic differentiation as well as neurite growth and guidance within grafts and during development. Furthermore we identify stromal derived factor 1 (SDF1), secreted by the meninges and acting on the CXCR4 receptor present on dopaminergic progenitors, as a contributory mediator in these effects. These findings identify new and important roles for the meningeal cells, and SDF1/CXCR4 signaling, in ventral midbrain development as well as neural repair following cell transplantation into the Parkinsonian brain.
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Affiliation(s)
- Fahad A Somaa
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Christopher R Bye
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Lachlan H Thompson
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Clare L Parish
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria 3010, Australia.
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30
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Fernando CV, Kele J, Bye CR, Niclis JC, Alsanie W, Blakely BD, Stenman J, Turner BJ, Parish CL. Diverse roles for Wnt7a in ventral midbrain neurogenesis and dopaminergic axon morphogenesis. Stem Cells Dev 2014; 23:1991-2003. [PMID: 24803261 DOI: 10.1089/scd.2014.0166] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
During development of the central nervous system, trophic, together with genetic, cues dictate the balance between cellular proliferation and differentiation. Subsequent to the birth of new neurons, additional intrinsic and extrinsic signals regulate the connectivity of these cells. While a number of regulators of ventral midbrain (VM) neurogenesis and dopaminergic (DA) axon guidance are known, we identify a number of novel roles for the secreted glycoprotein, Wnt7a, in this context. We demonstrate a temporal and spatial expression of Wnt7a in the VM, indicative of roles in neurogenesis, differentiation, and axonal growth and guidance. In primary VM cultures, and validated in Wnt7a-deficient mice, we show that the early expression within the VM is important for regulating VM progenitor proliferation, cell cycle progression, and cell survival, thereby dictating the number of midbrain Nurr1 precursors and DA neurons. During early development of the midbrain DA pathways, Wnt7a promotes axonal elongation and repels DA neurites out of the midbrain. Later, Wnt7a expression in the VM midline suggests a role in preventing axonal crossing while expression in regions flanking the medial forebrain bundle (thalamus and hypothalamus) ensured appropriate trajectory of DA axons en route to their forebrain targets. We show that the effects of Wnt7a in VM development are mediated, at least in part, by the β-catenin/canonical pathways. Together, these findings identify Wnt7a as a new regulator of VM neurogenesis and DA axon growth and guidance.
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Affiliation(s)
- Chathurini V Fernando
- 1 The Florey Institute of Neuroscience and Mental Health, The University of Melbourne , Parkville, Australia
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31
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Stott SRW, Barker RA. Time course of dopamine neuron loss and glial response in the 6-OHDA striatal mouse model of Parkinson's disease. Eur J Neurosci 2014; 39:1042-1056. [PMID: 24372914 DOI: 10.1111/ejn.12459] [Citation(s) in RCA: 96] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Revised: 10/22/2013] [Accepted: 11/19/2013] [Indexed: 01/02/2023]
Abstract
The 6-hydroxydopamine (6-OHDA) neurotoxic lesion of the midbrain dopamine (DA) system is one of the most widely used techniques for modelling Parkinson's disease in rodents. The majority of studies using this approach, however, largely limit their analysis to lesioning acutely, and looking at behavioural deficits and the number of surviving tyrosine hydroxylase (TH)-stained cells in the midbrain. Here we have analysed additional characteristics that occur following intrastriatal delivery of 6-OHDA, providing better understanding of the neurodegenerative process. Female C57/Black mice were given lesions at 10 weeks old, and killed at several different time points postoperatively (3 and 6 h, 1, 3, 6, 9 and 12 days). While the detrimental effect of the toxin on the TH+ fibres in the striatum was immediate, we found that the loss of TH+ dendritic fibres, reduction in cell size and intensity of TH expression, and eventual reduction in the number of TH+ neurons in the substantia nigra was delayed for several days post-surgery. We also investigated the expression of various transcription factors and proteins expressed by midbrain DA neurons following lesioning, and observed changes in the expression of Aldh1a1 (aldehyde dehydrogenase 1 family, member A1) as the neurodegenerative process evolved. Extracellularly, we looked at microglia and astrocytes in reaction to the 6-OHDA striatal lesion, and found a delay in their response and proliferation in the substantia nigra. In summary, this work highlights aspects of the neurodegenerative process in the 6-OHDA mouse model that can be applied to future studies looking at therapeutic interventions.
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Affiliation(s)
- Simon R W Stott
- John van Geest Centre for Brain Repair, Forvie Site, Robinson Way, Cambridge, CB2 0PY, UK
| | - Roger A Barker
- John van Geest Centre for Brain Repair, Forvie Site, Robinson Way, Cambridge, CB2 0PY, UK
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32
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Adolescent stimulation of D2 receptors alters the maturation of dopamine-dependent goal-directed behavior. Neuropsychopharmacology 2013; 38:1566-74. [PMID: 23443719 PMCID: PMC3682151 DOI: 10.1038/npp.2013.55] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Adolescence is a period of high sensitivity to drugs and rewards, characterized by the immaturity of decision-making abilities. A chronic stimulation of reward systems during this period might constitute a factor of vulnerability to the development of psychiatric disorders. However, the long-term consequences of such an exposure have seldom been explored. Here, we investigate at the adult age the effects of chronic dopamine (DA) stimulation during adolescence on both the maturation of DA systems and the cognitive processes underlying goal-directed actions. We first demonstrate that chronic stimulation of D2 receptors by quinpirole during adolescence alters the development of DA systems. This treatment has particularly prominent effects on the mesocortical DA pathway where it decreases DA fibers density, DA concentration, and DA receptors expression. Furthermore, we show that quinpirole-treated rats exhibit specific impairments in instrumental goal-directed behavior, as they fail to adapt their action when action-outcome relationships change in a contingency degradation procedure. These results therefore highlight the vulnerability of DA system and prefrontal areas to prolonged stimulation during adolescence, and its potential long-term impact on cognitive functions.
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Blakely BD, Bye CR, Fernando CV, Prasad AA, Pasterkamp RJ, Macheda ML, Stacker SA, Parish CL. Ryk, a receptor regulating Wnt5a-mediated neurogenesis and axon morphogenesis of ventral midbrain dopaminergic neurons. Stem Cells Dev 2013; 22:2132-44. [PMID: 23517308 DOI: 10.1089/scd.2013.0066] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Ryk is an atypical transmembrane receptor tyrosine kinase that has been shown to play multiple roles in development through the modulation of Wnt signaling. Within the developing ventral midbrain (VM), Wnts have been shown to contribute to the proliferation, differentiation, and connectivity of dopamine (DA) neurons; however, the Wnt-related receptors regulating these events remain less well described. In light of the established roles of Wnt5a in dopaminergic development (regulating DA differentiation as well as axonal growth and repulsion), and its interaction with Ryk elsewhere within the central nervous system, we investigated the potential role of Ryk in VM development. Here we show temporal and spatial expression of Ryk within the VM, suggestive of a role in DA neurogenesis and axonal plasticity. In VM primary cultures, we show that the effects of Wnt5a on VM progenitor proliferation, DA differentiation, and DA axonal connectivity can be inhibited using an Ryk-blocking antibody. In support, Ryk knockout mice showed reduced VM progenitors and DA precursor populations, resulting in a significant decrease in DA cells. However, Ryk(-/-) mice displayed no defects in DA axonal growth, guidance, or fasciculation of the MFB, suggesting other receptors may be involved and/or compensate for the loss of this receptor. These findings identify for the first time Ryk as an important receptor for midbrain DA development.
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Affiliation(s)
- Brette D Blakely
- Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Australia
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Oaks AW, Frankfurt M, Finkelstein DI, Sidhu A. Age-dependent effects of A53T alpha-synuclein on behavior and dopaminergic function. PLoS One 2013; 8:e60378. [PMID: 23560093 PMCID: PMC3613356 DOI: 10.1371/journal.pone.0060378] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2012] [Accepted: 02/25/2013] [Indexed: 11/30/2022] Open
Abstract
Expression of A53T mutant human alpha-synuclein under the mouse prion promoter is among the most successful transgenic models of Parkinson's disease. Accumulation of A53T alpha-synuclein causes adult mice to develop severe motor impairment resulting in early death at 8–12 months of age. In younger, pre-symptomatic animals, altered motor activity and anxiety-like behaviors have also been reported. These behavioral changes, which precede severe neuropathology, may stem from non-pathological functions of alpha-synuclein, including modulation of monoamine neurotransmission. Our analysis over the adult life-span of motor activity, anxiety-like, and depressive-like behaviors identifies perturbations both before and after the onset of disease. Young A53T mice had increased distribution of the dopamine transporter (DAT) to the membrane that was associated with increased striatal re-uptake function. DAT function decreased with aging, and was associated with neurochemical alterations that included increased expression of beta-synuclein and gamma synuclein. Prior to normalization of dopamine uptake, transient activation of Tau kinases and hyperphosphorylation of Tau in the striatum were also observed. Aged A53T mice had reduced neuron counts in the substantia nigra pars compacta, yet striatal medium spiny neuron dendritic spine density was largely maintained. These findings highlight the involvement of the synuclein family of proteins and phosphorylation of Tau in the response to dopaminergic dysfunction of the nigrostriatal pathway.
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Affiliation(s)
- Adam W. Oaks
- Laboratory of Molecular Neurochemistry, Department of Biochemistry and Molecular & Cellular Biology, Georgetown University Medical Center, Washington, D.C., United States of America
| | - Maya Frankfurt
- Department of Science Education, Hofstra North Shore-LIJ School of Medicine, Hempstead, New York, United States of America
| | - David I. Finkelstein
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Victoria, Australia
| | - Anita Sidhu
- Laboratory of Molecular Neurochemistry, Department of Biochemistry and Molecular & Cellular Biology, Georgetown University Medical Center, Washington, D.C., United States of America
- * E-mail:
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35
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Fusar-Poli P, Meyer-Lindenberg A. Striatal presynaptic dopamine in schizophrenia, Part I: meta-analysis of dopamine active transporter (DAT) density. Schizophr Bull 2013; 39:22-32. [PMID: 22282456 PMCID: PMC3523907 DOI: 10.1093/schbul/sbr111] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
BACKGROUND Striatal dopaminergic neurotransmission has been postulated to be fundamental to the emergence of key symptoms of schizophrenia, such as psychotic symptoms, and is targeted by currently available dopaminergic drugs. A specific marker of the integrity of presynaptic dopamine neurons in the striatum, the density of striatal dopamine terminals, can be quantified through molecular neuroimaging of the dopamine active transporter (DAT). However, the currently available results using this approach in schizophrenia are inconsistent. METHODS Thirteen Single Photon Emission Tomography or Positron Emission Tomography (PET) studies investigating DAT density in the striatum of schizophrenic patients and matched controls were included in a quantitative meta-analysis. Binding potentials in the striatum, caudate, and putamen, as well as demographic, clinical, and methodological variables, were extracted from each publication. Hedges' g was used as a measure of effect size. RESULTS The overall database contained 202 subjects with schizophrenia and 147 controls, well matched with respect to sociodemographic variables. Striatal DAT density was not significantly different between patients and controls. Similar negative findings were regionally confirmed in the putamen and caudate. There was no moderating effect for external factors. CONCLUSIONS Our meta-analysis uncovered no evidence indicating altered density of striatal dopamine terminals in schizophrenia. Moreover, striatal DAT density did not seem to be influenced by antipsychotic medication or illness duration. Our data suggest that altered integrity of striatal dopaminergic synapses is not critical for the emergence of schizophrenia or its treatment. These findings should be useful in further refining dopaminergic hypotheses of schizophrenia.
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Affiliation(s)
- Paolo Fusar-Poli
- Section of Psychiatry, Department of Health Sciences, University of Pavia, Pavia, Italy.
| | - Andreas Meyer-Lindenberg
- Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
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36
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Kauhausen J, Thompson LH, Parish CL. Cell intrinsic and extrinsic factors contribute to enhance neural circuit reconstruction following transplantation in Parkinsonian mice. J Physiol 2012; 591:77-91. [PMID: 23045338 DOI: 10.1113/jphysiol.2012.243063] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Cell replacement therapy for Parkinson's disease has predominantly focused on ectopic transplantation of fetal dopamine (DA) neurons into the striatum as a means to restore neurotransmission, rather than homotopic grafts into the site of cell loss, which would require extensive axonal growth. However, ectopic grafts fail to restore important aspects of DA circuitry necessary for controlled basal ganglia output, and this may underlie the suboptimal and variable functional outcomes in patients. We recently showed that DA neurons in homotopic allografts of embryonic ventral mesencephalon (VM) can send long axonal projections along the nigrostriatal pathway in order to innervate forebrain targets, although the extent of striatal reinnervation remains substantially less than can be achieved with ectopic placement directly into the striatal target. Here, we examined the possible benefits of using younger VM donor tissue and over-expression of glial cell-derived neurotrophic factor (GDNF) in the striatal target to improve the degree of striatal innervation from homotopic grafts. Younger donor tissue, collected on embryonic day (E)10, generated 4-fold larger grafts with greater striatal targeting, compared to grafts generated from more conventional E12 donor VM. Over-expression of GDNF in the host brain also significantly increased DA axonal growth and striatal innervation. Furthermore, a notable increase in the number and proportion of A9 DA neurons, essential for functional recovery, was observed in younger donor grafts treated with GDNF. Behavioural testing confirmed functional integration of younger donor tissue and demonstrated that improved motor function could be attributed to both local midbrain and striatal innervation. Together, these findings suggest there is significant scope for further development of intra-nigral grafting as a restorative approach for Parkinson's disease.
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Affiliation(s)
- Jessica Kauhausen
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria 3010, Australia
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Bye CR, Thompson LH, Parish CL. Birth dating of midbrain dopamine neurons identifies A9 enriched tissue for transplantation into parkinsonian mice. Exp Neurol 2012; 236:58-68. [PMID: 22524988 DOI: 10.1016/j.expneurol.2012.04.002] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2012] [Revised: 04/02/2012] [Accepted: 04/07/2012] [Indexed: 01/08/2023]
Abstract
Clinical trials have provided proof of principle that new dopamine neurons isolated from the developing ventral midbrain and transplanted into the denervated striatum can functionally integrate and alleviate symptoms in Parkinson's disease patients. However, extensive variability across patients has been observed, ranging from long-term motor improvement to the absence of symptomatic relief and development of dyskinesias. Heterogeneity of the donor tissue is likely to be a contributing factor in the variable outcomes. Dissections of ventral midbrain used for transplantation will variously contain progenitors for different dopamine neuron subtypes as well as different neurotransmitter phenotypes. The overall impact of the resulting graft will be determined by the functional contribution from these different cell types. The A9 substantia nigra pars compacta dopamine neurons, for example, are known to be particularly important for motor recovery in animal models. Serotonergic neurons, on the other hand, have been implicated in unwanted dyskinesias. Currently little knowledge exists on how variables such as donor age, which have not been controlled for in clinical trials, will impact on the final neuronal composition of fetal grafts. Here we performed a birth dating study to identify the time-course of neurogenesis within the various ventral midbrain dopamine subpopulations in an effort to identify A9-enriched donor tissue for transplantation. The results show that A9 neurons precede the birth of A10 ventral tegmental area dopamine neurons. Subsequent grafting of younger ventral midbrain donor tissue revealed significantly larger grafts containing more mitotic dopamine neuroblasts compared to older donor grafts. These grafts were enriched with A9 neurons and showed significantly greater innervation of the target dorso-lateral striatum and DA release. Younger donor grafts also contained significantly less serotonergic neurons. These findings demonstrate the importance of standardized methods to improve cell therapy for Parkinson's disease and have significant implications for the generation and selectivity of dopamine neurons from stem cell based sources.
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Affiliation(s)
- Christopher R Bye
- Florey Neuroscience Institutes, The University of Melbourne, Parkville, Victoria 3010, Australia
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Hung LW, Villemagne VL, Cheng L, Sherratt NA, Ayton S, White AR, Crouch PJ, Lim S, Leong SL, Wilkins S, George J, Roberts BR, Pham CLL, Liu X, Chiu FCK, Shackleford DM, Powell AK, Masters CL, Bush AI, O'Keefe G, Culvenor JG, Cappai R, Cherny RA, Donnelly PS, Hill AF, Finkelstein DI, Barnham KJ. The hypoxia imaging agent CuII(atsm) is neuroprotective and improves motor and cognitive functions in multiple animal models of Parkinson's disease. ACTA ACUST UNITED AC 2012; 209:837-54. [PMID: 22473957 PMCID: PMC3328361 DOI: 10.1084/jem.20112285] [Citation(s) in RCA: 131] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The PET imaging agent CuII(atsm) improves motor and cognitive function in Parkinson’s disease. Parkinson’s disease (PD) is a progressive, chronic disease characterized by dyskinesia, rigidity, instability, and tremors. The disease is defined by the presence of Lewy bodies, which primarily consist of aggregated α-synuclein protein, and is accompanied by the loss of monoaminergic neurons. Current therapeutic strategies only give symptomatic relief of motor impairment and do not address the underlying neurodegeneration. Hence, we have identified CuII(atsm) as a potential therapeutic for PD. Drug administration to four different animal models of PD resulted in improved motor and cognition function, rescued nigral cell loss, and improved dopamine metabolism. In vitro, this compound is able to inhibit the effects of peroxynitrite-driven toxicity, including the formation of nitrated α-synuclein oligomers. Our results show that CuII(atsm) is effective in reversing parkinsonian defects in animal models and has the potential to be a successful treatment of PD.
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Affiliation(s)
- Lin W Hung
- The Mental Health Research Institute, the University of Melbourne, Victoria 3010 Australia
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Zeng X, Shen H, Zhao J, Cai Q, Wang C, Xu Q. Long-term changes in morphology, D2R expression and targets of regenerated dopaminergic terminals in the striatum after a partial lesion in the substantia nigra in the rat. Brain Res 2012; 1450:166-73. [DOI: 10.1016/j.brainres.2012.02.047] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2011] [Revised: 02/07/2012] [Accepted: 02/17/2012] [Indexed: 10/28/2022]
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Neckameyer WS, Bhatt P. Neurotrophic actions of dopamine on the development of a serotonergic feeding circuit in Drosophila melanogaster. BMC Neurosci 2012; 13:26. [PMID: 22413901 PMCID: PMC3364880 DOI: 10.1186/1471-2202-13-26] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2011] [Accepted: 03/13/2012] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND In the fruit fly, Drosophila melanogaster, serotonin functions both as a neurotransmitter to regulate larval feeding, and in the development of the stomatogastric feeding circuit. There is an inverse relationship between neuronal serotonin levels during late embryogenesis and the complexity of the serotonergic fibers projecting from the larval brain to the foregut, which correlate with perturbations in feeding, the functional output of the circuit. Dopamine does not modulate larval feeding, and dopaminergic fibers do not innervate the larval foregut. Since dopamine can function in central nervous system development, separate from its role as a neurotransmitter, the role of neuronal dopamine was assessed on the development, and mature function, of the 5-HT larval feeding circuit. RESULTS Both decreased and increased neuronal dopamine levels in late embryogenesis during development of this circuit result in depressed levels of larval feeding. Perturbations in neuronal dopamine during this developmental period also result in greater branch complexity of the serotonergic fibers innervating the gut, as well as increased size and number of the serotonin-containing vesicles along the neurite length. This neurotrophic action for dopamine is modulated by the D2 dopamine receptor expressed during late embryogenesis in central 5-HT neurons. Animals carrying transgenic RNAi constructs to knock down both dopamine and serotonin synthesis in the central nervous system display normal feeding and fiber architecture. However, disparate levels of neuronal dopamine and serotonin during development of the circuit result in abnormal gut fiber architecture and feeding behavior. CONCLUSIONS These results suggest that dopamine can exert a direct trophic influence on the development of a specific neural circuit, and that dopamine and serotonin may interact with each other to generate the neural architecture necessary for normal function of the circuit.
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Affiliation(s)
- Wendi S Neckameyer
- Department of Pharmacological and Physiological Science, Saint Louis University School of Medicine, 1402 South Grand Boulevard, Saint Louis, Missouri 63104, USA
| | - Parag Bhatt
- Department of Pharmacological and Physiological Science, Saint Louis University School of Medicine, 1402 South Grand Boulevard, Saint Louis, Missouri 63104, USA
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Reduced proliferation in the adult mouse subventricular zone increases survival of olfactory bulb interneurons. PLoS One 2012; 7:e31549. [PMID: 22363671 PMCID: PMC3283653 DOI: 10.1371/journal.pone.0031549] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2011] [Accepted: 01/13/2012] [Indexed: 11/25/2022] Open
Abstract
Neurogenesis in the adult brain is largely restricted to the subependymal zone (SVZ) of the lateral ventricle, olfactory bulb (OB) and the dentate subgranular zone, and survival of adult-born cells in the OB is influenced by factors including sensory experience. We examined, in mice, whether survival of adult-born cells is also regulated by the rate of precursor proliferation in the SVZ. Precursor proliferation was decreased by depleting the SVZ of dopamine after lesioning dopamine neurons in the substantia nigra compacta with 6-hydroxydopamine. Subsequently, we examined the effect of reduced SVZ proliferation on the generation, migration and survival of neuroblasts and mature adult-born cells in the SVZ, rostral migratory stream (RMS) and OB. Proliferating cells in the SVZ, measured by 5-bromo-2-deoxyuridine (BrdU) injected 2 hours prior to death or by immunoreactivity against Ki67, were reduced by 47% or 36%, respectively, 7 days after dopamine depletion, and by 29% or 31% 42 days after dopamine depletion, compared to sham-treated animals. Neuroblast generation in the SVZ and their migration along the RMS were not affected, neither 7 nor 42 days after the 6-hydroxydopamine injection, since the number of doublecortin-immunoreactive neuroblasts in the SVZ and RMS, as well as the number of neuronal nuclei-immunoreactive cells in the OB, were stable compared to control. However, survival analysis 15 days after 6-hydroxydopamine and 6 days after BrdU injections showed that the number of BrdU+ cells in the SVZ was 70% higher. Also, 42 days after 6-hydroxydopamine and 30 days after BrdU injections, we found an 82% increase in co-labeled BrdU+/γ-aminobutyric acid-immunoreactive cell bodies in the granular cell layer, while double-labeled BrdU+/tyrosine hydroxylase-immunoreactive cell bodies in the glomerular layer increased by 148%. We conclude that the number of OB interneurons following reduced SVZ proliferation is maintained through an increased survival of adult-born precursor cells, neuroblasts and interneurons.
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Walker QD, Johnson ML, Van Swearingen AED, Arrant AE, Caster JM, Kuhn CM. Individual differences in psychostimulant responses of female rats are associated with ovarian hormones and dopamine neuroanatomy. Neuropharmacology 2012; 62:2267-77. [PMID: 22342988 DOI: 10.1016/j.neuropharm.2012.01.029] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2011] [Revised: 01/26/2012] [Accepted: 01/30/2012] [Indexed: 10/14/2022]
Abstract
Ovarian hormones modulate the pharmacological effects of psychostimulants and may enhance vulnerability to drug addiction. Female rats have more midbrain dopamine neurons than males and greater dopamine uptake and release rates. Cocaine stimulates motor behavior and dopamine efflux more in female than male rats, but the mediating mechanisms are unknown. This study investigated individual differences in anatomic, neurochemical, and behavioral measures in female rats to understand how ovarian hormones affect the relatedness of these endpoints. Ovarian hormone effects were assessed by comparing individual responses in ovariectomized (OVX) and sham adult female rats. Locomotion was determined before and following 10mg/kg cocaine. Electrically-stimulated dopamine efflux was assessed using fast cyclic voltammetry in vivo. Dopamine neuron number and density in substantia nigra (SN) and ventral tegmental area (VTA) were determined in the same animals using tyrosine-hydroxylase immunohistochemistry and unbiased stereology. Locomotor behavior and dopamine efflux did not differ at baseline but were greater in sham than OVX following cocaine. Cocaine increased dopamine release rates in both groups but uptake inhibition (K(m)) was greater in sham than OVX. Dopamine neuron number and density in SN and VTA were greater in shams. Sham females with the largest uterine weights exhibited the highest density of dopamine neurons in the SN, and the most cocaine-stimulated behavior and dopamine efflux. Ovariectomy eliminated these relationships. We postulate that SN density could link ovarian hormones and high-psychostimulant responses in females. Similar mechanisms may be involved in individual differences in the addiction vulnerability of women.
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Affiliation(s)
- Q David Walker
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC 27710, USA.
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Gutierrez-Valdez AL, Anaya-Martínez V, Ordoñez-Librado JL, García-Ruiz R, Torres-Esquivel C, Moreno-Rivera M, Sánchez-Betancourt J, Montiel-Flores E, Avila-Costa MR. Effect of chronic L-dopa or melatonin treatments after dopamine deafferentation in rats: dyskinesia, motor performance, and cytological analysis. ISRN NEUROLOGY 2012; 2012:360379. [PMID: 22462019 PMCID: PMC3302121 DOI: 10.5402/2012/360379] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/05/2011] [Accepted: 10/20/2011] [Indexed: 12/02/2022]
Abstract
The present study examines the ability of melatonin to protect striatal dopaminergic loss induced by 6-OHDA in a rat model of Parkinson's disease, comparing the results with L-DOPA-treated rats. The drugs were administered orally daily for a month, their therapeutic or dyskinetic effects were assessed by means of abnormal involuntary movements (AIMs) and stepping ability. At the cellular level, the response was evaluated using tyrosine hydroxylase immunoreactivity and striatal ultrastructural changes to compare between L-DOPA-induced AIMs and Melatonin-treated rats. Our findings demonstrated that chronic oral administration of Melatonin improved the alterations caused by the neurotoxin 6-OHDA. Melatonin-treated animals perform better in the motor tasks and had no dyskinetic alterations compared to L-DOPA-treated group. At the cellular level, we found that Melatonin-treated rats showed more TH-positive neurons and their striatal ultrastructure was well preserved. Thus, Melatonin is a useful treatment to delay the cellular and behavioral alterations observed in Parkinson's disease.
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Affiliation(s)
- Ana Luisa Gutierrez-Valdez
- Laboratorio de Neuromorfologia, Departamento de Neurociencias, Facultad de Estudios Superiores Iztacala, UNAM, Avenida de los Barrios 1, Los Reyes Iztacala, 54090 Tlalnepantla, MEX, Mexico
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Crabtree DM, Zhang J. Genetically engineered mouse models of Parkinson's disease. Brain Res Bull 2011; 88:13-32. [PMID: 21839151 DOI: 10.1016/j.brainresbull.2011.07.019] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2011] [Revised: 07/01/2011] [Accepted: 07/22/2011] [Indexed: 12/26/2022]
Abstract
Parkinson's disease (PD) is the most common neurodegenerative movement disorder, affecting more than 1% of the population over age 60. The most common feature of PD is a resting tremor, though there are many systemic neurological effects, such as incontinence and sleep disorders. PD is histopathologically identified by the presence of Lewy bodies (LB), proteinaceous inclusions constituted primarily by α-synuclein. To date, there is no effective treatment to slow or stop disease progression. To help understand disease pathogenesis and identify potential therapeutic targets, many genetic mouse models have been developed. By far the most common of these models are the wildtype and mutant α-synuclein transgenic mice, because α-synuclein was the first protein shown to have a direct effect on PD pathogenesis and progression. There are many other gene-disrupted or -mutated models currently available, which are based on genetic anomalies identified in the human disease. In addition, there are also models which examine genes that may contribute to disease onset or progression but currently have no identified causative PD mutations. These genes are part of signaling pathways important for maintaining neuronal function in the nigrostriatal pathway. This review will summarize the most commonly used of the genetic mouse models currently available for PD research. We will examine how these models have expanded our understanding of PD pathogenesis and progression, as well as aided in identification of potential therapeutic targets in this disorder.
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Affiliation(s)
- Donna M Crabtree
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
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Lipski J, Nistico R, Berretta N, Guatteo E, Bernardi G, Mercuri NB. L-DOPA: a scapegoat for accelerated neurodegeneration in Parkinson's disease? Prog Neurobiol 2011; 94:389-407. [PMID: 21723913 DOI: 10.1016/j.pneurobio.2011.06.005] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2011] [Revised: 06/17/2011] [Accepted: 06/17/2011] [Indexed: 12/21/2022]
Abstract
There is consensus that amelioration of the motor symptoms of Parkinson's disease is most effective with L-DOPA (levodopa). However, this necessary therapeutic step is biased by an enduring belief that L-DOPA is toxic to the remaining substantia nigra dopaminergic neurons by itself, or by specific metabolites such as dopamine. The concept of L-DOPA toxicity originated from pre-clinical studies conducted mainly in cell culture, demonstrating that L-DOPA or its derivatives damage dopaminergic neurons due to oxidative stress and other mechanisms. However, the in vitro data remain controversial as some studies showed neuroprotective, rather than toxic action of the drug. The relevance of this debate needs to be considered in the context of the studies conducted on animals and in clinical trials that do not provide convincing evidence for L-DOPA toxicity in vivo. This review presents the current views on the pathophysiology of Parkinson's disease, focusing on mitochondrial dysfunction and oxidative/proteolytic stress, the factors that can be affected by L-DOPA or its metabolites. We then critically discuss the evidence supporting the two opposing views on the effects of L-DOPA in vitro, as well as the animal and human data. We also address the problem of inadequate experimental models used in these studies. L-DOPA remains the symptomatic 'hero' of Parkinson's disease. Whether it contributes to degeneration of nigral dopaminergic neurons, or is a 'scapegoat' for explaining undesirable or unexpected effects of the treatment, remains a hotly debated topic.
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Affiliation(s)
- Janusz Lipski
- Department of Physiology and Centre for Brain Research, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Rd., Auckland 1142, New Zealand.
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Blakely BD, Bye CR, Fernando CV, Horne MK, Macheda ML, Stacker SA, Arenas E, Parish CL. Wnt5a regulates midbrain dopaminergic axon growth and guidance. PLoS One 2011; 6:e18373. [PMID: 21483795 PMCID: PMC3069098 DOI: 10.1371/journal.pone.0018373] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2010] [Accepted: 03/04/2011] [Indexed: 11/19/2022] Open
Abstract
During development, precise temporal and spatial gradients are responsible for
guiding axons to their appropriate targets. Within the developing ventral
midbrain (VM) the cues that guide dopaminergic (DA) axons to their forebrain
targets remain to be fully elucidated. Wnts are morphogens that have been
identified as axon guidance molecules. Several Wnts are expressed in the VM
where they regulate the birth of DA neurons. Here, we describe that a precise
temporo-spatial expression of Wnt5a accompanies the development of nigrostriatal
projections by VM DA neurons. In mice at E11.5, Wnt5a is
expressed in the VM where it was found to promote DA neurite and axonal growth
in VM primary cultures. By E14.5, when DA axons are approaching their striatal
target, Wnt5a causes DA neurite retraction in primary cultures. Co-culture of VM
explants with Wnt5a-overexpressing cell aggregates revealed that Wnt5a is
capable of repelling DA neurites. Antagonism experiments revealed that the
effects of Wnt5a are mediated by the Frizzled receptors and by the small GTPase,
Rac1 (a component of the non-canonical Wnt planar cell polarity pathway).
Moreover, the effects were specific as they could be blocked by Wnt5a antibody,
sFRPs and RYK-Fc. The importance of Wnt5a in DA axon morphogenesis was further
verified in Wnt5a−/− mice, where
fasciculation of the medial forebrain bundle (MFB) as well as the density of DA
neurites in the MFB and striatal terminals were disrupted. Thus, our results
identify a novel role of Wnt5a in DA axon growth and guidance.
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Affiliation(s)
- Brette D. Blakely
- Florey Neuroscience Institutes, The University of Melbourne, Victoria,
Australia
- Centre for Neurosciences, The University of Melbourne, Victoria,
Australia
| | - Christopher R. Bye
- Florey Neuroscience Institutes, The University of Melbourne, Victoria,
Australia
| | | | - Malcolm K. Horne
- Florey Neuroscience Institutes, The University of Melbourne, Victoria,
Australia
- Centre for Neurosciences, The University of Melbourne, Victoria,
Australia
- St Vincent's Hospital, Fitzroy, Victoria, Australia
| | - Maria L. Macheda
- Ludwig Institute for Cancer Research, Royal Melbourne Hospital,
Parkville, Victoria, Australia
| | - Steven A. Stacker
- Ludwig Institute for Cancer Research, Royal Melbourne Hospital,
Parkville, Victoria, Australia
| | - Ernest Arenas
- Laboratory of Molecular Neurobiology, Department of Biochemistry and
Biophysics, Karolinska Institute, Stockholm, Sweden
| | - Clare L. Parish
- Florey Neuroscience Institutes, The University of Melbourne, Victoria,
Australia
- Centre for Neurosciences, The University of Melbourne, Victoria,
Australia
- * E-mail:
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Liu J, Wang H, Zhang L, Xu Y, Deng W, Zhu H, Qin C. S100B Transgenic Mice Develop Features of Parkinson's Disease. Arch Med Res 2011; 42:1-7. [DOI: 10.1016/j.arcmed.2011.01.005] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2010] [Accepted: 12/22/2010] [Indexed: 11/30/2022]
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Kern CH, Smith DR. Preweaning Mn exposure leads to prolonged astrocyte activation and lasting effects on the dopaminergic system in adult male rats. Synapse 2010; 65:532-44. [PMID: 20963817 DOI: 10.1002/syn.20873] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2010] [Accepted: 09/28/2010] [Indexed: 01/18/2023]
Abstract
Little is known about the effects of manganese (Mn) exposure over neurodevelopment and whether these early insults result in effects lasting into adulthood. To determine if early Mn exposure produces lasting neurobehavioral and neurochemical effects, we treated neonate rats with oral Mn (0, 25, or 50 mg Mn/kg/d over PND 1-21) and evaluated (1) behavioral performance in the open arena in the absence (PND 97) and presence (PND 98) of a d-amphetamine challenge, (2) brain dopamine D1 and D2-like receptors and dopamine transporter densities in the prefrontal cortex, striatum, and nucleus accumbens (PND 107), and (3) astrocyte marker glial fibrillary acidic protein (GFAP) levels in these same brain regions (PND 24 and 107). We found that preweaning Mn exposure did not alter locomotor activity or behavior disinhibition in adult rats, though Mn-exposed animals did exhibit an enhanced locomotor response to d-amphetamine challenge. Preweaning Mn exposure led to increased D1 and D2 receptor levels in the nucleus accumbens and prefrontal cortex, respectively, compared with controls. We also found increased GFAP expression in the prefrontal cortex in Mn-exposed PND 24 weanlings, and increased GFAP levels in prefrontal cortex, medial striatum and nucleus accumbens of adult (PND 107) rats exposed to preweaning Mn, indicating an effect of Mn exposure on astrogliosis that persisted and/or progressed to other brain regions in adult animals. These data show that preweaning Mn exposure leads to lasting molecular and functional impacts in multiple brain regions of adult animals, long after brain Mn levels returned to normal.
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Affiliation(s)
- Cynthia H Kern
- Department of Microbiology and Environmental Toxicology, University of California, Santa Cruz, California 95064, USA
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Chronic cocaine administration reduces striatal dopamine terminal density and striatal dopamine release which leads to drug-seeking behaviour. Neuroscience 2010; 174:143-50. [PMID: 21129449 DOI: 10.1016/j.neuroscience.2010.11.055] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2010] [Revised: 11/23/2010] [Accepted: 11/27/2010] [Indexed: 11/22/2022]
Abstract
Drug addiction is associated with altered dopamine (DA) neurotransmission in the basal ganglia. We have previously shown that chronic stimulation of the dopamine D2 receptor (D(2)R) with cocaine results in reduced striatal DA terminal density. The aims of this study were to establish whether this reduction in DA terminal density results in reduced striatal DA release and increased cocaine-seeking behaviour and whether D(2)R antagonism can restore the cocaine-induced alterations in DA neurotransmission and drug-seeking behaviour. Rats were housed individually and either control, cocaine, haloperidol (D(2)R antagonist), or cocaine and haloperidol was administered in the drinking water for 16 weeks. Chronic cocaine treatment, which reduced striatal DA terminal density by 20%, resulted in a reduction in basal (-34%) and cocaine-evoked (-33%) striatal DA release and increased cocaine-seeking behaviour. These cocaine-mediated effects on striatal DA terminal density, DA release and drug-seeking could be prevented by co-administration with haloperidol. Basal and cocaine-evoked DA release in the striatum directly correlated with DA terminal density and with preference for cocaine. We conclude that striatal DA terminal density and DA release is an important factor in maintaining drug preference and should be considered as a factor in drug-seeking behaviour and relapse.
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50
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Fazio L, Blasi G, Taurisano P, Papazacharias A, Romano R, Gelao B, Ursini G, Quarto T, Lo Bianco L, Di Giorgio A, Mancini M, Popolizio T, Rubini G, Bertolino A. D2 receptor genotype and striatal dopamine signaling predict motor cortical activity and behavior in humans. Neuroimage 2010; 54:2915-21. [PMID: 21087673 DOI: 10.1016/j.neuroimage.2010.11.034] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2010] [Revised: 11/08/2010] [Accepted: 11/09/2010] [Indexed: 01/30/2023] Open
Abstract
OBJECTIVE Pre-synaptic D2 receptors regulate striatal dopamine release and DAT activity, key factors for modulation of motor pathways. A functional SNP of DRD2 (rs1076560 G>T) is associated with alternative splicing such that the relative expression of D2S (mainly pre-synaptic) vs. D2L (mainly post-synaptic) receptor isoforms is decreased in subjects with the T allele with a putative increase of striatal dopamine levels. To evaluate how DRD2 genotype and striatal dopamine signaling predict motor cortical activity and behavior in humans, we have investigated the association of rs1076560 with BOLD fMRI activity during a motor task. To further evaluate the relationship of this circuitry with dopamine signaling, we also explored the correlation between genotype based differences in motor brain activity and pre-synaptic striatal DAT binding measured with [(123)I] FP-CIT SPECT. METHODS Fifty healthy subjects, genotyped for DRD2 rs1076560 were studied with BOLD-fMRI at 3T while performing a visually paced motor task with their right hand; eleven of these subjects also underwent [(123)I]FP-CIT SPECT. SPM5 random-effects models were used for statistical analyses. RESULTS Subjects carrying the T allele had greater BOLD responses in left basal ganglia, thalamus, supplementary motor area, and primary motor cortex, whose activity was also negatively correlated with reaction time at the task. Moreover, left striatal DAT binding and activity of left supplementary motor area were negatively correlated. INTERPRETATION The present results suggest that DRD2 genetic variation was associated with focusing of responses in the whole motor network, in which activity of predictable nodes was correlated with reaction time and with striatal pre-synaptic dopamine signaling. Our results in humans may help shed light on genetic risk for neurobiological mechanisms involved in the pathophysiology of disorders with dysregulation of striatal dopamine like Parkinson's disease.
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Affiliation(s)
- Leonardo Fazio
- Department of Neurological and Psychiatric Sciences, University of Bari Aldo Moro, Bari, Italy
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