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Matar E, Bhatia K. Dystonia and Parkinson's disease: Do they have a shared biology? INTERNATIONAL REVIEW OF NEUROBIOLOGY 2023; 169:347-411. [PMID: 37482398 DOI: 10.1016/bs.irn.2023.05.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/25/2023]
Abstract
Parkinsonism and dystonia co-occur across many movement disorders and are most encountered in the setting of Parkinson's disease. Here we aim to explore the shared neurobiological underpinnings of dystonia and parkinsonism through the clinical lens of the conditions in which these movement disorders can be seen together. Foregrounding the discussion, we briefly review the circuits of the motor system and the neuroanatomical and neurophysiological aspects of motor control and highlight their relevance to the proposed pathophysiology of parkinsonism and dystonia. Insight into shared biology is then sought from dystonia occurring in PD and other forms of parkinsonism including those disorders in which both can be co-expressed simultaneously. We organize these within a biological schema along with important questions to be addressed in this space.
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Affiliation(s)
- Elie Matar
- UCL Queen Square Institute of Neurology Department of Clinical and Movement Neurosciences, Queen Square, London, United Kingdom; Central Clinical School, Faculty of Medicine and Health, University of Sydney, Sydney, Australia.
| | - Kailash Bhatia
- UCL Queen Square Institute of Neurology Department of Clinical and Movement Neurosciences, Queen Square, London, United Kingdom
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2
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Alosaimi F, Boonstra JT, Tan S, Temel Y, Jahanshahi A. The role of neurotransmitter systems in mediating deep brain stimulation effects in Parkinson’s disease. Front Neurosci 2022; 16:998932. [PMID: 36278000 PMCID: PMC9579467 DOI: 10.3389/fnins.2022.998932] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Accepted: 09/14/2022] [Indexed: 11/24/2022] Open
Abstract
Deep brain stimulation (DBS) is among the most successful paradigms in both translational and reverse translational neuroscience. DBS has developed into a standard treatment for movement disorders such as Parkinson’s disease (PD) in recent decades, however, specific mechanisms behind DBS’s efficacy and side effects remain unrevealed. Several hypotheses have been proposed, including neuronal firing rate and pattern theories that emphasize the impact of DBS on local circuitry but detail distant electrophysiological readouts to a lesser extent. Furthermore, ample preclinical and clinical evidence indicates that DBS influences neurotransmitter dynamics in PD, particularly the effects of subthalamic nucleus (STN) DBS on striatal dopaminergic and glutamatergic systems; pallidum DBS on striatal dopaminergic and GABAergic systems; pedunculopontine nucleus DBS on cholinergic systems; and STN-DBS on locus coeruleus (LC) noradrenergic system. DBS has additionally been associated with mood-related side effects within brainstem serotoninergic systems in response to STN-DBS. Still, addressing the mechanisms of DBS on neurotransmitters’ dynamics is commonly overlooked due to its practical difficulties in monitoring real-time changes in remote areas. Given that electrical stimulation alters neurotransmitter release in local and remote regions, it eventually exhibits changes in specific neuronal functions. Consequently, such changes lead to further modulation, synthesis, and release of neurotransmitters. This narrative review discusses the main neurotransmitter dynamics in PD and their role in mediating DBS effects from preclinical and clinical data.
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Affiliation(s)
- Faisal Alosaimi
- Department of Neurosurgery, Maastricht University Medical Centre, Maastricht, Netherlands
- Department of Physiology, Faculty of Medicine, King Abdulaziz University, Rabigh, Saudi Arabia
- *Correspondence: Faisal Alosaimi,
| | - Jackson Tyler Boonstra
- Department of Neurosurgery, Maastricht University Medical Centre, Maastricht, Netherlands
| | - Sonny Tan
- Department of Neurosurgery, Maastricht University Medical Centre, Maastricht, Netherlands
| | - Yasin Temel
- Department of Neurosurgery, Maastricht University Medical Centre, Maastricht, Netherlands
| | - Ali Jahanshahi
- Department of Neurosurgery, Maastricht University Medical Centre, Maastricht, Netherlands
- Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences, Amsterdam, Netherlands
- Ali Jahanshahi,
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Seillier C, Lesept F, Toutirais O, Potzeha F, Blanc M, Vivien D. Targeting NMDA Receptors at the Neurovascular Unit: Past and Future Treatments for Central Nervous System Diseases. Int J Mol Sci 2022; 23:ijms231810336. [PMID: 36142247 PMCID: PMC9499580 DOI: 10.3390/ijms231810336] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 08/30/2022] [Accepted: 09/02/2022] [Indexed: 11/16/2022] Open
Abstract
The excitatory neurotransmission of the central nervous system (CNS) mainly involves glutamate and its receptors, especially N-methyl-D-Aspartate receptors (NMDARs). These receptors have been extensively described on neurons and, more recently, also on other cell types. Nowadays, the study of their differential expression and function is taking a growing place in preclinical and clinical research. The diversity of NMDAR subtypes and their signaling pathways give rise to pleiotropic functions such as brain development, neuronal plasticity, maturation along with excitotoxicity, blood-brain barrier integrity, and inflammation. NMDARs have thus emerged as key targets for the treatment of neurological disorders. By their large extracellular regions and complex intracellular structures, NMDARs are modulated by a variety of endogenous and pharmacological compounds. Here, we will present an overview of NMDAR functions on neurons and other important cell types involved in the pathophysiology of neurodegenerative, neurovascular, mental, autoimmune, and neurodevelopmental diseases. We will then discuss past and future development of NMDAR targeting drugs, including innovative and promising new approaches.
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Affiliation(s)
- Célia Seillier
- Normandie University, UNICAEN, INSERM, GIP Cyceron, Institute Blood and Brain @Caen-Normandie (BB@C), UMR-S U1237, Physiopathology and Imaging of Neurological Disorders (PhIND), 14000 Caen, France
| | - Flavie Lesept
- Lys Therapeutics, Cyceron, Boulevard Henri Becquerel, 14000 Caen, France
| | - Olivier Toutirais
- Normandie University, UNICAEN, INSERM, GIP Cyceron, Institute Blood and Brain @Caen-Normandie (BB@C), UMR-S U1237, Physiopathology and Imaging of Neurological Disorders (PhIND), 14000 Caen, France
- Department of Immunology and Histocompatibility (HLA), Caen University Hospital, CHU, 14000 Caen, France
| | - Fanny Potzeha
- Lys Therapeutics, Cyceron, Boulevard Henri Becquerel, 14000 Caen, France
| | - Manuel Blanc
- Lys Therapeutics, Cyceron, Boulevard Henri Becquerel, 14000 Caen, France
| | - Denis Vivien
- Normandie University, UNICAEN, INSERM, GIP Cyceron, Institute Blood and Brain @Caen-Normandie (BB@C), UMR-S U1237, Physiopathology and Imaging of Neurological Disorders (PhIND), 14000 Caen, France
- Department of Clinical Research, Caen University Hospital, CHU, 14000 Caen, France
- Correspondence:
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Nakajima T, Suzuki Y, Miyaue N. Successful Management of Parkinson's Disease Dyskinesia During Local Anesthesia With Dexmedetomidine. Cureus 2021; 13:e13739. [PMID: 33842117 PMCID: PMC8020600 DOI: 10.7759/cureus.13739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Dyskinesia is among the most problematic issues for local anaesthesia management in Parkinson's disease (PD) patients. We present a case of a patient with PD who underwent spinal anaesthesia while utilizing dexmedetomidine (DEX) to reduce dyskinesia during urological surgery. DEX stimulates α₂-adrenergic receptors, which works to reduce the dyskinesia in PD patients.
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Affiliation(s)
- Takamichi Nakajima
- Center for Medical Education and Training, Saiseikai Matsuyama Hospital, Matsuyama, JPN
| | - Yasuyuki Suzuki
- Anesthesiology, Saiseikai Matsuyama Hospital, Matsuyama, JPN
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Borroto-Escuela DO, Fuxe K. Adenosine heteroreceptor complexes in the basal ganglia are implicated in Parkinson's disease and its treatment. J Neural Transm (Vienna) 2019; 126:455-471. [PMID: 30637481 PMCID: PMC6456481 DOI: 10.1007/s00702-019-01969-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Accepted: 01/06/2019] [Indexed: 02/08/2023]
Abstract
The adenosine homo, iso and heteroreceptor complexes in the basal ganglia play a highly significant role in modulating the indirect and direct pathways and the striosomal projections to the nigro-striatal DA system. The major adenosine receptor complexes in the striato-pallidal GABA neurons can be the A2AR-D2R and A2AR-D2R-mGluR5 receptor complexes, in which A2AR protomers and mGluR5 protomers can allosterically interact to inhibit D2R protomer signaling. Through a reorganization of these heteroreceptor complexes upon chronic dopaminergic treatment a pathological and prolonged inhibition of D2R receptor protomer signaling can develop with motor inhibition and wearing off of the therapeutic effects of levodopa and dopamine receptor agonists. The direct pathway is enriched in D1R in and around glutamate synapses enhancing the ability of these GABA neurons to be activated and increase motor initiation. The brake on these GABA neurons is in this case exerted by A1R forming A1R-D1R heteroreceptor complexes in which they allosterically inhibit D1R signaling and thereby reduce motor initiation. Upon chronic levodopa treatment a reorganization of the D1R heteroreceptor complexes develops with the formation of putative A1R-D1R-D3 in addition to D1R-D3R complexes in which D3R enhances D1R protomer signaling and may make the A1R protomer brake less effective. Alpha-synuclein monomers-dimers are postulated to form complexes with A2AR homo and heteroprotomers in the plasma membrane enhancing alpha-synuclein aggregation and toxicity. The alpha-synuclein fibrils formed in the A2AR enriched dendritic spines of the striato-pallidal GABA neurons may reach the surrounding DA terminals via extracellular-vesicle-mediated volume transmission involving internalization of the vesicles and their cargo (alpha-synuclein fibrils) into the vulnerable DA terminals, enhancing their degeneration followed by retrograde flow of these fibrils in the DA axons to the vulnerable nigral DA nerve cells.
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Affiliation(s)
- Dasiel O. Borroto-Escuela
- Department of Neuroscience, Karolinska Institutet, Biomedicum, B0851, Solnavägen 9, 17177 Stockholm, Sweden
- Observatorio Cubano de Neurociencias, Grupo Bohío-Estudio, Zayas 50, 62100 Yaguajay, Cuba
| | - Kjell Fuxe
- Department of Neuroscience, Karolinska Institutet, Biomedicum, B0851, Solnavägen 9, 17177 Stockholm, Sweden
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Roberts DP, Lewis SJG. Considerations for general anaesthesia in Parkinson's disease. J Clin Neurosci 2017; 48:34-41. [PMID: 29133106 DOI: 10.1016/j.jocn.2017.10.062] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Accepted: 10/23/2017] [Indexed: 12/19/2022]
Abstract
Parkinson's disease is a common neurodegenerative disorder in the elderly which when present has a significant influence on surgical management. These patients necessitate additional perioperative and anaesthetic considerations across disease specific domains as well as in relation to the respiratory and cardiovascular systems. This brief review focuses on the factors which contribute to perioperative morbidity, including the use of medications that may exacerbate symptoms or adversely interact with treatments for Parkinson's disease. Recommended dosing practices to reduce complications during hospitalisation are covered. In addition, recent concerns regarding anaesthetic exposure in early childhood as a risk factor for the development of Parkinson's disease are discussed in light of data from animal models of anaesthetic neurotoxicity and epidemiological studies.
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Affiliation(s)
| | - Simon J G Lewis
- Parkinson's Disease Research Clinic, Brain and Mind Centre, University of Sydney, NSW, Australia.
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Non-human primate models of PD to test novel therapies. J Neural Transm (Vienna) 2017; 125:291-324. [PMID: 28391443 DOI: 10.1007/s00702-017-1722-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 04/04/2017] [Indexed: 12/13/2022]
Abstract
Non-human primate (NHP) models of Parkinson disease show many similarities with the human disease. They are very useful to test novel pharmacotherapies as reviewed here. The various NHP models of this disease are described with their characteristics including the macaque, the marmoset, and the squirrel monkey models. Lesion-induced and genetic models are described. There is no drug to slow, delay, stop, or cure Parkinson disease; available treatments are symptomatic. The dopamine precursor, L-3,4-dihydroxyphenylalanine (L-Dopa) still remains the gold standard symptomatic treatment of Parkinson. However, involuntary movements termed L-Dopa-induced dyskinesias appear in most patients after chronic treatment and may become disabling. Dyskinesias are very difficult to manage and there is only amantadine approved providing only a modest benefit. In this respect, NHP models have been useful to seek new drug targets, since they reproduce motor complications observed in parkinsonian patients. Therapies to treat motor symptoms in NHP models are reviewed with a discussion of their translational value to humans. Disease-modifying treatments tested in NHP are reviewed as well as surgical treatments. Many biochemical changes in the brain of post-mortem Parkinson disease patients with dyskinesias are reviewed and compare well with those observed in NHP models. Non-motor symptoms can be categorized into psychiatric, autonomic, and sensory symptoms. These symptoms are present in most parkinsonian patients and are already installed many years before the pre-motor phase of the disease. The translational usefulness of NHP models of Parkinson is discussed for non-motor symptoms.
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Morin N, Di Paolo T. Pharmacological Treatments Inhibiting Levodopa-Induced Dyskinesias in MPTP-Lesioned Monkeys: Brain Glutamate Biochemical Correlates. Front Neurol 2014; 5:144. [PMID: 25140165 PMCID: PMC4122180 DOI: 10.3389/fneur.2014.00144] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Accepted: 07/18/2014] [Indexed: 12/21/2022] Open
Abstract
Anti-glutamatergic drugs can relieve Parkinson’s disease (PD) symptoms and decrease l-3,4-dihydroxyphenylalanine (l-DOPA)-induced dyskinesias (LID). This review reports relevant studies investigating glutamate receptor subtypes in relation to motor complications in PD patients and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-lesioned monkeys. Antagonists of the ionotropic glutamate receptors, such as N-methyl-d-aspartate (NMDA) and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors, display antidyskinetic activity in PD patients and animal models such as the MPTP monkey. Metabotropic glutamate 5 (mGlu5) receptor antagonists were shown to reduce the severity of LID in PD patients as well as in already dyskinetic non-human primates and to prevent the development of LID in de novo treatments in non-human primates. An increase in striatal post-synaptic NMDA, AMPA, and mGlu5 receptors is documented in PD patients and MPTP monkeys with LID. This increase can be prevented in MPTP monkeys with the addition of a specific glutamate receptor antagonist to the l-DOPA treatment and also with drugs of various pharmacological specificities suggesting multiple receptor interactions. This is yet to be well documented for presynaptic mGlu4 and mGlu2/3 and offers additional new promising avenues.
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Affiliation(s)
- Nicolas Morin
- Neuroscience Research Unit, Centre de Recherche du CHU de Québec , Quebec City, QC , Canada ; Faculty of Pharmacy, Laval University , Quebec City, QC , Canada
| | - Thérèse Di Paolo
- Neuroscience Research Unit, Centre de Recherche du CHU de Québec , Quebec City, QC , Canada ; Faculty of Pharmacy, Laval University , Quebec City, QC , Canada
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9
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Modeling dyskinesia in animal models of Parkinson disease. Exp Neurol 2014; 256:105-16. [DOI: 10.1016/j.expneurol.2013.01.024] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2012] [Revised: 01/12/2013] [Accepted: 01/21/2013] [Indexed: 01/23/2023]
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Morin N, Di Paolo T. Interaction of adenosine receptors with other receptors from therapeutic perspective in Parkinson's disease. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2014; 119:151-67. [PMID: 25175965 DOI: 10.1016/b978-0-12-801022-8.00007-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Altered dopaminergic neurotransmission in the basal ganglia is observed in Parkinson's disease (PD) and L-3,4-dihydroxyphenylalanine (L-DOPA)-induced dyskinesias (LID). An attractive alternative for treating LID is to use adjunct drugs to modulate nondopaminergic neurotransmitter systems in the basal ganglia. For example, adenosine receptors have received attention over the past years for the treatment of PD and LID. Adenosine interacts closely with dopamine and plays an important role in the function of striatal GABAergic efferent neurons. Excitatory glutamatergic neurotransmission is also modulated by adenosine in the striatum. Hence, based on the unique cellular and regional distribution of this system, adenosine neurotransmission could have an important implication for the development of new therapeutic strategies targeting the basal ganglia disorders. Indeed, A2A adenosine receptor antagonists were shown to improve motor deficits in PD and to reduce the severity of LID. A2A receptor subtypes are selectively found on striatopallidal neurons and can couple with receptors of interest in PD, such as D2 dopamine and metabotropic glutamate receptor type 5 (mGlu5) receptors, and form functional heteromeric complexes. This chapter will review relevant studies investigating the role and contribution of adenosine receptor subtypes in pathophysiology of PD and LID. The interactions of adenosine receptors, especially A1 and A2A receptor subtypes, with other receptors implicated in the pathophysiology of PD and LID such as dopaminergic and glutamatergic receptors will be reviewed. The implication of these interactions in the development and expression of PD symptoms and LID needs further investigation to find novel drug targets.
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Affiliation(s)
- Nicolas Morin
- Neuroscience Research Unit, Centre de recherche du CHU de Québec, Quebec, Quebec, Canada; Faculty of Pharmacy, Laval University, Quebec, Quebec, Canada
| | - Thérèse Di Paolo
- Neuroscience Research Unit, Centre de recherche du CHU de Québec, Quebec, Quebec, Canada; Faculty of Pharmacy, Laval University, Quebec, Quebec, Canada.
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Breger LS, Lane EL. L-DOPA and graft-induced dyskinesia: different treatment, same story? Exp Biol Med (Maywood) 2013; 238:725-32. [PMID: 23828589 DOI: 10.1177/1535370213488478] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
One of the well-recognized problems of long-term L-3,4-dihydroxyphenylalanine (L-DOPA) therapy in the treatment of Parkinson's disease is the development of L-DOPA induced dyskinesia. These abnormal movements cause significant disability and narrow the therapeutic window of L-DOPA. Cell transplantation is one of the most promising upcoming therapies for the treatment of Parkinson's disease, and may help alleviate or avoid L-DOPA-induced dyskinesia. However, the more recently acknowledged phenomenon of graft-induced dyskinesia is posing a major obstacle to the success of this treatment. This motor side-effect closely resembles abnormal movements induced by chronic L-DOPA treatment, yet they remain after withdrawal of the medication indicating their origins lie in the transplant. In this review, we compare these two therapy-induced adverse effects, from the way they manifest in patients to the possible mechanisms underlying their development.
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Affiliation(s)
- Ludivine S Breger
- School of Pharmacy and Pharmaceutical Sciences, Cardiff University, Cardiff, CF10 3NB, UK
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Billet F, Costentin J, Dourmap N. Influence of corticostriatal δ-opioid receptors on abnormal involuntary movements induced by L-DOPA in hemiparkinsonian rats. Exp Neurol 2012; 236:339-50. [DOI: 10.1016/j.expneurol.2012.04.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2011] [Revised: 04/12/2012] [Accepted: 04/23/2012] [Indexed: 12/20/2022]
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Kreil A, Hamann M, Sander SE, Richter A. Changes in dynorphin immunoreactivity but unaltered density of enkephalin immunoreactive neurons in basal ganglia nuclei of genetically dystonic hamsters. Synapse 2011; 65:1196-203. [PMID: 21638337 DOI: 10.1002/syn.20959] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2011] [Revised: 05/21/2011] [Accepted: 05/24/2011] [Indexed: 12/12/2022]
Abstract
Dystonia is regarded as a basal ganglia disorder. In the dt(sz) hamster, a genetic animal model of paroxysmal dystonia, previous studies demonstrated a reduced density of striatal GABAergic interneurons which inhibit striatal GABAergic projection neurons. Although the disinhibition of striatal GABAergic projection neurons was evidenced in the dt(sz) hamster, alterations in their density have not been elucidated so far. Therefore, in the present study, the density of striatal methionin-(met-) enkephalin (ENK) immunoreactive GABAergic neurons, which project to the globus pallidus (indirect pathway), was determined in dt(sz) and control hamsters to clarify a possible role of an altered ratio between striatal interneurons and projection neurons. Furthermore, the immunoreactivity of dynorphin A (DYN), which is expressed in entopeduncular fibers of striatal neurons of the direct pathway, was verified by gray level measurements to illuminate the functional relevance of an enhanced striato-entopeduncular neuronal activity previously found in dt(sz) hamsters. While the density of striatal ENK immunoreactive (ENK(+) ) neurons did not significantly differ between mutant and control hamsters, there was a significantly enhanced ratio between the DYN immunoreactive area and the whole area of the EPN in dt(sz) hamsters compared to controls. These results support the hypothesis that a disbalance between a reduced density of striatal interneurons and an unchanged density of striatal projection neurons causes imbalances in the basal ganglia network. The consequentially enhanced striato-entopeduncular inhibition leads to an already evidenced reduced activity and an altered firing pattern of entopeduncular neurons in the dt(sz) hamster.
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Affiliation(s)
- Annette Kreil
- Institute of Pharmacology and Toxicology, Department of Veterinary Medicine, Freie Universität Berlin, Koserstrasse 20, 14195 Berlin, Germany
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Tsui A, Isacson O. Functions of the nigrostriatal dopaminergic synapse and the use of neurotransplantation in Parkinson's disease. J Neurol 2011; 258:1393-405. [PMID: 21544566 DOI: 10.1007/s00415-011-6061-6] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2011] [Revised: 04/12/2011] [Accepted: 04/14/2011] [Indexed: 10/18/2022]
Abstract
While pharmaceutical options remain the overwhelmingly accepted treatment of choice for neurological and psychiatric diseases, significant accomplishments in regenerative neuroscience research have demonstrated the potential of cellular and synaptic functional repair in future therapies. Parkinson's disease stands out as an example in which repair by dopaminergic neurons appears a viable potential therapy. This article describes the basic neurobiological underpinnings of the rationale for cell therapy for Parkinson's disease and the challenges ahead for the use of regenerative medicine in the treatment for this disease.
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Affiliation(s)
- Alex Tsui
- University of Oxford Medical School, John Radcliffe Hospital, Oxford, UK.
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Stefani A, Pierantozzi M, Koch G, Galati S, Stanzione P. Therapy for dyskinesias in Parkinson’s disease patients. FUTURE NEUROLOGY 2010. [DOI: 10.2217/fnl.10.9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Dyskinesia hampers the quality of life for most Parkinson’s disease patients following several years of therapy. However, the severity of L-Dopa-induced dyskinesia (LID) varies between patients, being quite tolerable in late-onset patients. Understanding the pathogenesis of LID has contributed to the development of a set of therapeutic strategies, including the choice, in early stages, of the least pulsatile regimen of dopamine-receptor activation. In cases where LIDs are already disabling, there is only a limited number of options: the optimization of ongoing DOPA-centered treatment, the utilization of glutamate antagonists and the exploration of the benefits of antipsychotic agents. More radical solutions are provided by deep brain stimulation in the subthalamic nucleus (or internal pallidus). This approach has proved efficacious in reducing LID, largely because it allows a reduction in dopaminergic daily doses. Stereotactic neurosurgery has fuelled several lines of investigation regarding the crosstalk between the basal ganglia and motor cortex. Here, we will present interesting evidence highlighting the potential for repetitive transcranial stimulation in reducing the occurrence of LID. The future may disclose important new avenues for the treatment of LIDs, given the current development of promising agents that might target different facets of dyskinesia, such as the impairment of striatal plasticity and non-Dopaminergic contributors such as adenosine, nitric oxide and the nucleotide cascade.
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Affiliation(s)
- Alessandro Stefani
- Movement Disorder Centre, Department of Neuroscience, Clinica Neurologica, Policlinico Tor Vergata, Viale Montpellier 1, 00133 Rome, Italy and IRCCS Fondazione Santa Lucia, Via Ardeatina 306, 00173 Rome, Italy
| | - Mariangela Pierantozzi
- Movement Disorder Centre, Department of Neuroscience, Clinica Neurologica, Policlinico Tor Vergata, Viale Montpellier 1, 00133 Rome, Italy and IRCCS Fondazione Santa Lucia, Via Ardeatina 306, 00173 Rome, Italy
| | - Giacomo Koch
- Movement Disorder Centre, Department of Neuroscience, Clinica Neurologica, Policlinico Tor Vergata, Viale Montpellier 1, 00133 Rome, Italy and IRCCS Fondazione Santa Lucia, Via Ardeatina 306, 00173 Rome, Italy
| | - Salvatore Galati
- Movement Disorder Centre, Department of Neuroscience, Clinica Neurologica, Policlinico Tor Vergata, Viale Montpellier 1, 00133 Rome, Italy and IRCCS Fondazione Santa Lucia, Via Ardeatina 306, 00173 Rome, Italy
| | - Paolo Stanzione
- Movement Disorder Centre, Department of Neuroscience, Clinica Neurologica, Policlinico Tor Vergata, Viale Montpellier 1, 00133 Rome, Italy and IRCCS Fondazione Santa Lucia, Via Ardeatina 306, 00173 Rome, Italy
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Continuous rotigotine administration reduces dyskinesia resulting from pulsatile treatment with rotigotine or l-DOPA in MPTP-treated common marmosets. Exp Neurol 2010; 221:79-85. [DOI: 10.1016/j.expneurol.2009.10.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2009] [Revised: 10/01/2009] [Accepted: 10/03/2009] [Indexed: 11/22/2022]
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Abstract
L-DOPA (L-3,4-dihydroxyphenylalanine) remains the most effective drug for the treatment of Parkinson's disease. However, chronic use causes dyskinesia, a complex motor phenomenon that consists of two components: the execution of involuntary movements in response to drug administration, and the 'priming' phenomenon that underlies these movements' establishment and persistence. A reinterpretation of recent data suggests that priming for dyskinesia results from nigral denervation and the loss of striatal dopamine input, which alters glutamatergic synaptic connectivity in the striatum. The subsequent response of the abnormal basal ganglia to dopaminergic drugs determines the manner and timing of dyskinesia expression. The combination of nigral denervation and drug treatment establishes inappropriate signalling between the motor cortex and the striatum, leading to persistent dyskinesia.
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Continuous delivery of ropinirole reverses motor deficits without dyskinesia induction in MPTP-treated common marmosets. Exp Neurol 2008; 211:172-9. [DOI: 10.1016/j.expneurol.2008.01.019] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2007] [Revised: 01/15/2008] [Accepted: 01/21/2008] [Indexed: 11/17/2022]
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Galvan A, Wichmann T. GABAergic circuits in the basal ganglia and movement disorders. PROGRESS IN BRAIN RESEARCH 2007; 160:287-312. [PMID: 17499121 DOI: 10.1016/s0079-6123(06)60017-4] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
GABA is the major inhibitory neurotransmitter in the basal ganglia, and GABAergic pathways dominate information processing in most areas of these structures. It is therefore not surprising that abnormalities of GABAergic transmission are key elements in pathophysiologic models of movement disorders involving the basal ganglia. These include hypokinetic diseases such as Parkinson's disease, and hyperkinetic diseases, such as Huntington's disease or hemiballism. In this chapter, we will briefly review the major anatomic features of the GABAergic pathways in the basal ganglia, and then describe in greater detail the changes of GABAergic transmission, which are known to occur in movement disorders.
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Affiliation(s)
- Adriana Galvan
- Department of Neurology, School of Medicine and Yerkes National Primate Research Center, Emory University, Atlanta, GA 30322, USA.
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20
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Singh B, Wilson JH, Vasavada HH, Guo Z, Allore HG, Zeiss CJ. Motor deficits and altered striatal gene expression in aphakia (ak) mice. Brain Res 2007; 1185:283-92. [PMID: 17949697 DOI: 10.1016/j.brainres.2007.09.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2007] [Revised: 08/30/2007] [Accepted: 09/05/2007] [Indexed: 10/22/2022]
Abstract
Like humans with Parkinson's disease (PD), the ak mouse lacks the majority of the substantia nigra pars compacta (SNc) and experiences striatal denervation. The purpose of this study was to test whether motor abnormalities in the ak mouse progress over time, and whether motor function could be associated with temporal alterations in the striatal transcriptome. Ak and wt mice (28 to 180 days old) were tested using paradigms sensitive to nigrostriatal dysfunction. Results were analyzed using a linear mixed model. Ak mice significantly underperformed wt controls in rotarod, balance beam, string test, pole test and cotton shred tests at all ages examined. Motor performance in ak mice remained constant over the first 6 months of life, with the exception of the cotton shred test, in which ak mice exhibited marginal decline in performance. Dorsal striatal semi-quantitative RT-PCR for 19 dopaminergic, cholinergic, glutaminergic and catabolic genes was performed in 1- and 6-month-old groups of ak and wt mice. Preproenkephalin levels in ak mice were elevated in both age groups. Drd1, 3 and 4 levels declined over time, in contrast to increasing Drd2 expression. Additional findings included decreased Chrnalpha6 expression and elevated VGluT1 expression at both time points in ak mice and elevated AchE expression in young ak mice only. Results confirm that motor ability does not decline significantly for the first 6 months of life in ak mice. Their striatal gene expression patterns are consistent with dopaminergic denervation, and change over time, despite relatively unaltered motor performance.
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Affiliation(s)
- Bhupinder Singh
- Section of Comparative Medicine, Yale University, 375 Congress Ave., New Haven, CT 06519, USA
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21
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Bäckman CM, Shan L, Zhang Y, Hoffer BJ, Tomac AC. Alterations in prodynorphin, proenkephalin, and GAD67 mRNA levels in the aged human putamen: correlation with Parkinson's disease. J Neurosci Res 2007; 85:798-804. [PMID: 17203488 DOI: 10.1002/jnr.21164] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A real-time quantitative PCR approach was used to quantify mRNA levels corresponding to the neuropeptides enkephalin, dynorphin, and the 67-kDa isoform of glutamic acid decarboxylase (GAD67) in the human putamen from young and aged individuals as well as from aged patients affected by Parkinson's disease (PD). cDNA-specific primers were designed to amplify GAD67, proenkephalin (pENK), prodynorphin (pDYN), and the housekeeping genes glyceraldehydes-3-phosphate dehydrogenase (GAPDH) and guanine nucleotide binding protein, beta-peptide 2-like I (GNB2LI). GAPDH and GNB2LI mRNA levels were similarly expressed among the groups and were therefore used as endogenous reference genes. Normalized data showed that mRNA levels for both pENK and pDYN were reduced in the putamen of aged controls and aged individuals affected by PD, compared with young controls. In addition, we showed that GAD67 mRNA levels did not change during aging and PD. Further analyses showed no differences in mRNA levels, for pENK, pDYN, or GAD67 mRNA, between PD patients and aged matched controls. These findings contrast with animal models of parkinsonism, for which expression of pDYN, pENK, and GAD67 mRNA has been reported to change after striatal dopamine denervation. Compensatory mechanisms and regional differences within the human putamen as well as the severity index of the disease, clinical diagnosis, and response to phalmacological therapy are possible reasons for these results. The present study suggests that alteration of neuropeptide pathways in the human putamen may be involved in the functional deterioration of parts of the extrapyramidal system during aging.
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Affiliation(s)
- Cristina M Bäckman
- Cellular Neurobiology Branch, National Institute on Drug Abuse, National Institutes of Health, Baltimore, Maryland 21224, USA.
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22
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Jackson MJ, Smith LA, Al-Barghouthy G, Rose S, Jenner P. Decreased expression of l-dopa-induced dyskinesia by switching to ropinirole in MPTP-treated common marmosets. Exp Neurol 2007; 204:162-70. [PMID: 17113078 DOI: 10.1016/j.expneurol.2006.10.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2006] [Revised: 10/03/2006] [Accepted: 10/09/2006] [Indexed: 10/23/2022]
Abstract
Current concepts suggest that pulsatile stimulation of dopamine receptors following L-dopa administration leads to priming for dyskinesia in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine hydrochloride (MPTP)-treated primates, while continuous dopaminergic stimulation with long-acting dopamine agonists does not. We investigated whether L-dopa-induced dyskinesia is reduced by switching to a dopamine agonist. MPTP-treated marmosets received chronic treatment with L-dopa or ropinirole in doses producing equivalent motor activity and reversal of motor deficits. Administration of L-dopa led to the rapid onset of moderate to severe dyskinesia, whereas ropinirole produced only mild dyskinesia. Animals initially treated with L-dopa were switched to an equivalent dose of ropinirole and those treated with ropinirole were switched to an equivalent dose of L-dopa for 56 days. L-dopa-primed animals that were switched to ropinirole showed a trend towards a reduction of dyskinesia intensity, whereas animals initially treated with ropinirole and switched to L-dopa showed a trend toward increased dyskinesia intensity. A subsequent, acute L-dopa challenge reversed motor deficits and induced intense dyskinesia in both groups. This suggests that L-dopa leads to the priming and expression of dyskinesia, but that expression is not maintained when switching to a long-acting dopamine agonist. In contrast, dopamine agonists may prime for dyskinesia, but do not lead to its full expression.
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Affiliation(s)
- Michael J Jackson
- Neurodegenerative Diseases Research Centre, School of Health and Biomedical Sciences, King's College, London SE1 1UL, UK
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23
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Franklin SO, Jimenez R. Increases in preproenkephalin mRNA levels in the Syrian hamster: The influence of glucocorticoids is dependent on age and tissue. Brain Res 2006; 1086:65-75. [PMID: 16597437 DOI: 10.1016/j.brainres.2006.02.077] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2005] [Revised: 02/19/2006] [Accepted: 02/21/2006] [Indexed: 12/22/2022]
Abstract
In adult hamsters, basal proenkephalin (Penk) gene expression in adrenals is independent of glucocorticoids and glucocorticoid receptor blockade, by RU 486, increases striatal preproenkephalin (PPenk) mRNA levels. However, glucocorticoids maintain both basal and induced Penk gene expression in rat adrenal (medulla) and striatum. This suggests species and tissue-specific differences in Penk gene regulation. Since studies show temporal coordination in Penk gene expression in developing hamster adrenal and striatum, we tested the hypothesis that increasing PPenk mRNA levels are dependent, while basal levels are independent of glucocorticoids in developing hamsters. To facilitate this study, we examined the influence of glucocorticoids on the temporal increases in developing hamster PPenk mRNA observed in adrenals between postnatal days 0 and 4 and in striatum between postnatal days 12 and 48. PPenk mRNA levels were determined in hamster pups after treatment with increasing doses of metyrapone (an 11beta hydroxylase inhibitor) or with the glucocorticoid receptor antagonist RU 486 +/- metyrapone between postnatal days 2 and 4. Levels were also determined 36 days after hypophysectomy at age 16-17 days. Although plasma glucocorticoid levels and/or the influence from glucocorticoids were reduced, only developmental increases in PPenk mRNA are influenced by glucocorticoids in hamster adrenals, while basal adrenal mRNA levels are unchanged. However, pituitary influence on striatal PPenk mRNA levels appears complex and may involve steroid and/or non-steroid factors. These results suggest that glucocorticoids regulate hamster Penk gene expression via a mechanism that varies with age and tissue and functions during the induction of the Penk gene and not to maintain basal gene expression. Possible mechanisms and species variation are discussed.
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Affiliation(s)
- Steven O Franklin
- Program in the Neuroscience of Drug Abuse, Julius L. Chambers Biomedical/Biotechnology Research Institute, North Carolina Central University, 700 George Street, Durham, 27707, USA.
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24
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Morissette M, Dridi M, Calon F, Hadj Tahar A, Meltzer LT, Bédard PJ, Di Paolo T. Prevention of levodopa-induced dyskinesias by a selective NR1A/2BN-methyl-D-aspartate receptor antagonist in parkinsonian monkeys: Implication of preproenkephalin. Mov Disord 2006; 21:9-17. [PMID: 16127720 DOI: 10.1002/mds.20654] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Enkephalin is reported to play an important role in the pathophysiology of levodopa (LD) -induced dyskinesias. The present study investigated the effect of chronic treatment with a selective NR1A/2B N-methyl-D-aspartate (NMDA) receptor antagonist, CI-1041, on the expression of preproenkephalin-A (PPE-A) in brains of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) -treated monkeys in relation to the development of LD-induced dyskinesias. Four MPTP-monkeys received LD/benserazide alone; they all developed dyskinesias. Four other MPTP-monkeys received LD/benserazide plus CI-1041; only one of them developed mild dyskinesias at the end of the fourth week of treatment. Four normal monkeys and four saline-treated MPTP monkeys were also included. MPTP-treated monkeys had extensive and similar striatal dopamine denervation. An increase of PPE-A mRNA levels assayed by in situ hybridization was observed in the lateral putamen (rostral and caudal) and caudate nucleus (rostral) of saline-treated MPTP monkeys compared to controls, whereas no change or a small increase was observed in their medial parts. Striatal PPE-A mRNA levels remained elevated in LD-treated MPTP monkeys, whereas cotreatment with CI-1041 brought them back to control values. These findings suggest that chronic blockade of striatal NR1A/2B NMDA receptors with CI-1041 normalizes PPE-A mRNA expression and prevents the development of LD-induced dyskinesias in an animal model of Parkinson disease.
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Affiliation(s)
- Marc Morissette
- Molecular Endocrinology and Oncology Research Centre, Laval University Medical Centre, Quebec, Canada
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25
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Deogaonkar M, Subramanian T. Pathophysiological basis of drug-induced dyskinesias in Parkinson's disease. ACTA ACUST UNITED AC 2005; 50:156-68. [PMID: 16026845 DOI: 10.1016/j.brainresrev.2005.05.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2005] [Revised: 05/11/2005] [Accepted: 05/13/2005] [Indexed: 11/19/2022]
Abstract
Drug-induced dyskinesias (DID) represent a troublesome, dose-limiting, and common complication of long-term pharmacotherapy in Parkinson's disease (PD) patients. The pathophysiological basis and clinical nature of DID is of major interest for clinicians and neuroscientists. In this review article, we evaluate the theories of pathophysiology and molecular basis of DID, validity of various animal models used in DID related research, and electrophysiological characteristics of various basal ganglia nuclei during DID. We also discuss the relevance of various treatment strategies to the pathophysiological mechanisms.
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Affiliation(s)
- Milind Deogaonkar
- Department of Neuroscience, NB 20, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH 44195, USA.
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26
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Robelet S, Melon C, Guillet B, Salin P, Kerkerian-Le Goff L. Chronic L-DOPA treatment increases extracellular glutamate levels and GLT1 expression in the basal ganglia in a rat model of Parkinson's disease. Eur J Neurosci 2004; 20:1255-66. [PMID: 15341597 DOI: 10.1111/j.1460-9568.2004.03591.x] [Citation(s) in RCA: 119] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
There is growing experimental evidence for the implication of glutamate-mediated mechanisms both in the pathophysiology of Parkinson's disease and in the development of dyskinesias with long-term administration of L-3,4-dihydroxyphenylalanine (L-DOPA). However, the impact of this treatment on glutamate transmission in the basal ganglia has been poorly investigated. In this study, we examined the effects of 6-hydroxydopamine-induced lesion of nigral dopamine neurons with or without subsequent chronic L-DOPA treatment on several parameters of glutamate system function in the rat striatum and substantia nigra pars reticulata. All the lesioned animals treated with L-DOPA developed severe dyskinesias. Extracellular glutamate levels, measured by microdialysis in freely moving conditions, and gene expression of the glial glutamate transporter GLT1, assessed by in situ hybridization, were unaffected by dopamine lesion or L-DOPA treatment alone, but were both markedly increased on the lesion side of rats with subsequent L-DOPA treatment. No change in the expression of the vesicular glutamate transporters vGluT1 and vGluT2 was measured in striatum. These data show that chronic L-DOPA treatment leading to dyskinesias increases basal levels of glutamate function in basal ganglia. The L-DOPA-induced overexpression of GLT1 may represent a compensatory mechanism involving astrocytes to limit glutamate overactivity and subsequent toxic processes.
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Affiliation(s)
- S Robelet
- Interactions Cellulaires, Neurodégénérescence et Neuroplasticité, UMR 6186, 31 chemin Joseph Aiguier, 13402 Marseille cedex 20, France
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27
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Linazasoro G. Recent failures of new potential symptomatic treatments for Parkinson's disease: causes and solutions. Mov Disord 2004; 19:743-754. [PMID: 15254931 DOI: 10.1002/mds.20120] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
One major goal of current research in Parkinson's disease (PD) is the discovery of novel agents to improve symptomatic management. The object of these new treatments should be to provide effective symptom control throughout the course of the disease without the development of side effects such as motor and psychiatric complications. Results of several clinical trials of new treatment options reported in the past 2 years have shown negative or unsatisfactory results. Most of the drugs and surgical procedures used in these studies had been tested previously in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) monkeys as well as in the classic 6-hydroxydopamine-lesioned rat model. They raise several questions about the true reliability of animal studies, the adequacy of the working hypotheses and design of clinical trials, the validity of tools in current use to evaluate a specific effect, and the selectivity of the drugs used. All these factors may explain failure. This review focuses on pharmacological and surgical treatments tested to improve the management of patients with motor fluctuations and dyskinesias. Some of the recent trials and possible reasons for their lack of success are critically analysed. Finally, some suggestions to avoid further failures and improve results are proposed.
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Affiliation(s)
- Gurutz Linazasoro
- Centro de Neurología y Neurocirugía funcional, Clínica Quirón, San Sebastián, Guipúzcoa, Spain
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28
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Thanvi BR, Lo TCN. Long term motor complications of levodopa: clinical features, mechanisms, and management strategies. Postgrad Med J 2004; 80:452-8. [PMID: 15299154 PMCID: PMC1743071 DOI: 10.1136/pgmj.2003.013912] [Citation(s) in RCA: 108] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Levodopa is the most effective symptomatic treatment of Parkinson's disease. However, after an initial period of dramatic benefit, several limitations become apparent including, "dopa resistant" motor symptoms (postural abnormalities, freezing episodes, speech impairment), "dopa resistant" non-motor signs (autonomic dysfunction, mood and cognitive impairment, etc), and/or drug related side effects (especially psychosis, motor fluctuations, and dyskinesias). Motor complications include fluctuations, dyskinesias, and dystonias. They can be very disabling and difficult to treat. Therefore, strategies should ideally be developed to prevent them. Though mechanisms underlying motor complications are only partially understood, recent work has revealed the importance of pulsatile stimulation of postsynaptic dopamine receptors and the disease severity. As a result of intermittent stimulation there occurs a cascade of changes in cell signalling leading to upregulation of the N-methyl-D-aspartate subtype of gamma-aminobutryric acid-ergic neurones. Modified preparations of levodopa (controlled release preparations, liquid levodopa), catecholamine-o-methyltransferase inhibitors, dopamine agonists, amantidine, and various neurosurgical approaches have been used in the prevention and/or treatment of motor complications. Current management of motor complications is less than satisfactory. With better understanding of the pathogenetic mechanisms, it is hoped that future therapeutic strategies will provide a safer and targeted treatment.
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Affiliation(s)
- B R Thanvi
- Department of Integrated Medicine, Leicester Royal Infirmary, University Hospitals of Leicester NHS Trust, Infirmary Squire, Leicester LE1 5WW, UK.
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29
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Van Blercom N, Lasa A, Verger K, Masramón X, Sastre VM, Linazasoro G. Effects of gabapentin on the motor response to levodopa: a double-blind, placebo-controlled, crossover study in patients with complicated Parkinson disease. Clin Neuropharmacol 2004; 27:124-8. [PMID: 15190235 DOI: 10.1097/00002826-200405000-00007] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Motor fluctuations and dyskinesias affect many parkinsonian patients chronically treated with levodopa. Imbalance between gabaergic direct and indirect striatopallidal pathways may originate them. Manipulating GABA neurotransmission may be effective in the treatment of these patients. Gabapentin is an antiepileptic drug that increases the synthesis and release of GABA. Previous studies suggest that gabapentin may be useful in Parkinson disease (PD). OBJECTIVE To know the effects of gabapentin on the motor response to levodopa in PD patients with motor complications. DESIGN A randomized double-blind, placebo-controlled, cross-over trial with four weeks of treatment. SETTING A tertiary referral center. PARTICIPANTS Twenty subjects with PD and motor fluctuations and dyskinesias on stable antiparkinsonian treatment, took gabapentin up to a maximum dose of 2.400 mg/d in three doses and placebo. METHODS Three levodopa challenges were performed: at the beginning of the study and at the end of each period of treatment (4 weeks). Basal (off) and best (on) motor status were assessed by the UPDRS III. Latency to peak effect, magnitude of motor response (difference between "on" and "off" scores in the UPDRS III), duration of motor response and severity and duration of dyskinesias after each levodopa challenge were assessed. Patients' diaries were administered. RESULTS : Fifteen patients completed the study. A significant improvement in the basal UPDRS III resulting in a significant reduction in the magnitude of the motor response after gabapentin was obtained (P < 0.001). No other changes were observed, either on pharmacological parameters or in levodopa-induced dyskinesias. Number of daily hours spent in "on," "on with dyskinesias" and "off" also remained unchanged. Tolerance was good, dizziness being the most common side effect. CONCLUSION Gabapentin improved parkinsonian symptoms (basal UPDRS III and magnitude of the motor response) following levodopa. This improvement was not reflected in the daily motor situation of patients. Dyskinesias remained unchanged. Gabapentin was well tolerated. Further studies are needed to know the impact of these results in the long-term.
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Affiliation(s)
- N Van Blercom
- Centro de Neurología y Neurocirugía funcional, Clínica Quirón, San Sebastián, Spain
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Konradi C, Macías W, Dudman JT, Carlson RR. Striatal proenkephalin gene induction: coordinated regulation by cyclic AMP and calcium pathways. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 2003; 115:157-61. [PMID: 12877986 PMCID: PMC4205580 DOI: 10.1016/s0169-328x(03)00204-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Enkephalin modulates striatal function, thereby affecting motor performance and addictive behaviors. The proenkephalin gene is also used as a model to study cyclic AMP-mediated gene expression in striatal neurons. The second messenger pathway leading to proenkephalin expression demonstrates how cyclic AMP pathways are synchronized with depolarization. We show that cyclic AMP-mediated regulation of the proenkephalin gene is dependent on the activity of L-type Ca2+ channels. Inhibition of L-type Ca2+ channels blocks forskolin-mediated induction of proenkephalin. The Ca2+-activated kinase, Ca2+/calmodulin kinase, as well as the cyclic AMP-activated kinase, protein kinase A (PKA), are both necessary for the induction of the proenkephalin promoter. Similarly, both kinases are needed for the L-type Ca2+ channel-mediated induction of proenkephalin. This synchronization of second messenger pathways provides a coincidence mechanism that gates proenkephalin synthesis in striatal neurons, ensuring that levels are increased only in the presence of activated PKA and depolarization.
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Affiliation(s)
- Christine Konradi
- Laboratory of Neuroplasticity, McLean Hospital, Harvard Medical School, MRC215, 115 Mill St., Belmont, MA 02478, USA.
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