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Lees A, Tolosa E, Stocchi F, Ferreira JJ, Rascol O, Antonini A, Poewe W. Optimizing levodopa therapy, when and how? Perspectives on the importance of delivery and the potential for an early combination approach. Expert Rev Neurother 2023; 23:15-24. [PMID: 36729395 DOI: 10.1080/14737175.2023.2176220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
INTRODUCTION There is currently a resurgence of levodopa as the initial treatment of choice for most patients with Parkinson's disease, albeit at lower doses than previously used. The addition of adjuvant treatments (including MAO-B inhibitors, COMT inhibitors and dopamine agonists) is an established strategy to reduce motor complications that develop with sustained levodopa therapy. AREAS COVERED In this narrative review, the authors discuss the evidence underpinning current levodopa optimization strategies, during early disease and once motor complications occur. To support the discussion, the authors performed a broad PubMed search with the terms 'levodopa/L-dopa/L-Dopa, and Parkinson's disease,' restricted to clinical trials. There is now a wealth of evidence that improving levodopa delivery to the brain improves outcomes and we discuss how agents can be combined earlier in the course of disease to leverage the full potential of this strategy. EXPERT OPINION Levodopa remains the cornerstone of antiparkinsonian therapy. Several promising advances in formulation have been made and include novel extended-release oral drugs as well as non-oral delivery systems. However, evidence has long suggested that anti-parkinsonian medications may be better used in combination earlier in the disease, and consequently patients will benefit from low doses of several agents rather than ever larger levodopa doses.
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Affiliation(s)
- Andrew Lees
- University College London, Reta Lila Weston Institute, London, UK
| | - Eduardo Tolosa
- Parkinson disease and Movement Disorders Unit, Neurology Service, Hospital Clinic de Barcelona, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), University of Barcelona, Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED: CB06/05/0018-ISCIII) Barcelona, Barcelona, Spain
| | - Fabrizio Stocchi
- Department of Neurology, University San Raffaele and IRCCS San Raffaele Pisana, Rome, Italy
| | - Joaquim J Ferreira
- Laboratory of Clinical Pharmacology and Therapeutics, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal.,CNS - Campus Neurológico, Torres Vedras, Portugal
| | - Olivier Rascol
- Department of Neurosciences and Clinical Pharmacology, Clinical Investigation center CIC1436 and NS-Park/FCRIN network; University Hospital of Toulouse, INSERM and University of Toulouse 3, Toulouse, France
| | - Angelo Antonini
- Movement Disorders Unit, Study Center for Neurodegenerative Diseases (CESNE), Department of Neuroscience, University of Padova
| | - Werner Poewe
- Department of Neurology, Medical University of Innsbruck, Innsbruck, Austria
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Matt SM, Gaskill PJ. Dopaminergic impact of cART and anti-depressants on HIV neuropathogenesis in older adults. Brain Res 2019; 1723:146398. [PMID: 31442412 DOI: 10.1016/j.brainres.2019.146398] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2019] [Revised: 08/09/2019] [Accepted: 08/19/2019] [Indexed: 01/21/2023]
Abstract
The success of combination antiretroviral therapy (cART) has transformed HIV infection into a chronic condition, resulting in an increase in the number of older, cART-treated adults living with HIV. This has increased the incidence of age-related, non-AIDS comorbidities in this population. One of the most common comorbidities is depression, which is also associated with cognitive impairment and a number of neuropathologies. In older people living with HIV, treating these overlapping disorders is complex, often creating pill burden or adverse drug-drug interactions that can exacerbate these neurologic disorders. Depression, NeuroHIV and many of the neuropsychiatric therapeutics used to treat them impact the dopaminergic system, suggesting that dopaminergic dysfunction may be a common factor in the development of these disorders. Further, changes in dopamine can influence the development of inflammation and the regulation of immune function, which are also implicated in the progression of NeuroHIV and depression. Little is known about the optimal clinical management of drug-drug interactions between cART drugs and antidepressants, particularly in regard to dopamine in older people living with HIV. This review will discuss those interactions, first examining the etiology of NeuroHIV and depression in older adults, then discussing the interrelated effects of dopamine and inflammation on these disorders, and finally reviewing the activity and interactions of cART drugs and antidepressants on each of these factors. Developing better strategies to manage these comorbidities is critical to the health of the aging, HIV-infected population, as the older population may be particularly vulnerable to drug-drug interactions affecting dopamine.
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Finberg JPM. Inhibitors of MAO-B and COMT: their effects on brain dopamine levels and uses in Parkinson's disease. J Neural Transm (Vienna) 2018; 126:433-448. [PMID: 30386930 DOI: 10.1007/s00702-018-1952-7] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Accepted: 10/29/2018] [Indexed: 12/30/2022]
Abstract
MAO-B and COMT are both enzymes involved in dopamine breakdown and metabolism. Inhibitors of these enzymes are used in the treatment of Parkinson's disease. This review article describes the scientific background to the localization and function of the enzymes, the physiological changes resulting from their inhibition, and the basic and clinical pharmacology of the various inhibitors and their role in treatment of Parkinson's disease.
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Affiliation(s)
- John P M Finberg
- Neuroscience Group, Rappaport Faculty of Medicine, Haifa, Israel.
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Dixit A, Srivastava G, Verma D, Mishra M, Singh PK, Prakash O, Singh MP. Minocycline, levodopa and MnTMPyP induced changes in the mitochondrial proteome profile of MPTP and maneb and paraquat mice models of Parkinson's disease. Biochim Biophys Acta Mol Basis Dis 2013; 1832:1227-40. [PMID: 23562983 DOI: 10.1016/j.bbadis.2013.03.019] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2012] [Revised: 03/25/2013] [Accepted: 03/26/2013] [Indexed: 12/31/2022]
Abstract
Mitochondrial dysfunction is the foremost perpetrator of the nigrostriatal dopaminergic neurodegeneration leading to Parkinson's disease (PD). However, the roles played by majority of the mitochondrial proteins in PD pathogenesis have not yet been deciphered. The present study investigated the effects of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and combined maneb and paraquat on the mitochondrial proteome of the nigrostriatal tissues in the presence or absence of minocycline, levodopa and manganese (III) tetrakis (1-methyl-4-pyridyl) porphyrin (MnTMPyP). The differentially expressed proteins were identified and proteome profiles were correlated with the pathological and biochemical anomalies induced by MPTP and maneb and paraquat. MPTP altered the expression of twelve while combined maneb and paraquat altered the expression of fourteen proteins. Minocycline, levodopa and MnTMPyP, respectively, restored the expression of three, seven and eight proteins in MPTP and seven, eight and eight proteins in maneb- and paraquat-treated groups. Although levodopa and MnTMPyP rescued from MPTP- and maneb- and paraquat-mediated increase in the microglial activation and decrease in manganese-superoxide dismutase expression and complex I activity, dopamine content and number of dopaminergic neurons, minocycline defended mainly against maneb- and paraquat-mediated alterations. The results demonstrate that MPTP and combined maneb and paraquat induce mitochondrial dysfunction and microglial activation and alter the expression of a bunch of mitochondrial proteins leading to the nigrostriatal dopaminergic neurodegeneration and minocycline, levodopa or MnTMPyP variably offset scores of such changes.
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Affiliation(s)
- Anubhuti Dixit
- CSIR-Indian Institute of Toxicology Research CSIR-IITR, M. G. Marg, Post Box-80, Lucknow-226 001, UP, India
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Gerlach M, Halley P, Riederer P, van den Buuse M. The effect of piribedil on l-DOPA-induced dyskinesias in a rat model of Parkinson’s disease: differential role of α2 adrenergic mechanisms. J Neural Transm (Vienna) 2013; 120:31-6. [DOI: 10.1007/s00702-012-0818-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Accepted: 05/01/2012] [Indexed: 12/18/2022]
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Gerlach M, Beck J, Riederer P, van den Buuse M. Flibanserin attenuates l-DOPA-sensitized contraversive circling in the unilaterally 6-hydroxydopamine-lesioned rat model of Parkinson’s disease. J Neural Transm (Vienna) 2011; 118:1727-32. [DOI: 10.1007/s00702-010-0570-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2010] [Accepted: 12/17/2010] [Indexed: 02/07/2023]
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Gerlach M, Bartoszyk GD, Riederer P, Dean O, van den Buuse M. Role of dopamine D3 and serotonin 5-HT 1A receptors in L: -DOPA-induced dyskinesias and effects of sarizotan in the 6-hydroxydopamine-lesioned rat model of Parkinson's disease. J Neural Transm (Vienna) 2011; 118:1733-42. [PMID: 21253782 DOI: 10.1007/s00702-010-0571-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2010] [Accepted: 12/17/2010] [Indexed: 01/16/2023]
Abstract
Sarizotan, a 5-HT(1A) agonist with additional affinity for D(3) and D(4) receptors, has been demonstrated to have anti-dyskinetic effects. The mechanism by which these effects occur is not clear. Using unilateral 6-hydroxydopamine-lesioned rats that received chronic intraperitoneal (ip) administration of L: -3,4-dihydroxyphenylalanine (L: -DOPA) we investigated the involvement of D(3) and 5-HT(1A) receptors in the effects of sarizotan on contraversive circling and abnormal involuntary movements (AIMs). Before sensitization by chronic L: -DOPA treatment (12.5 with 3.25 mg/kg benserazide ip, twice daily for 21 days), no effect of the selective D(3) agonist, PD128907 (1 or 3 mg/kg ip), or the selective D(3) antagonist, GR103691 (0.5 or 1.5 mg/kg ip), was observed. Treatment with sarizotan (1 or 5 mg/kg ip) dose-dependently inhibited the L: -DOPA-induced contraversive turning and AIMs. In co-treatment with the 5-HT(1A) antagonist, WAY100635 (1 mg/kg ip), sarizotan failed to affect this behaviour, confirming the prominent 5-HT(1A) receptor-mediated mechanism of action. In the presence of PD128907 (3 mg/kg ip), the effects of sarizotan on contraversive turning, locomotive dyskinesia and axial dystonia, but not on orolingual and forelimb dyskinesia, were blocked. On its own, PD128907 had no effect on the behavioural effects of L: -DOPA except that it tended to reduce orolingual and forelimb dyskinesia. GR103691 had no effect on its own or in combination with sarizotan. These data identify an involvement of D(3) receptors in the action of sarizotan on some, but not all L: -DOPA-induced motor side effects. This selective involvement is in contrast to the more general involvement of 5-HT(1A) receptors in the anti-dyskinetic effects of sarizotan.
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Affiliation(s)
- Manfred Gerlach
- Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, Laboratory for Clinical Neurobiology, University of Würzburg, Füchsleinstrasse 15, 97080, Würzburg, Germany.
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Shah RS, Chang SY, Min HK, Cho ZH, Blaha CD, Lee KH. Deep brain stimulation: technology at the cutting edge. J Clin Neurol 2010; 6:167-82. [PMID: 21264197 PMCID: PMC3024521 DOI: 10.3988/jcn.2010.6.4.167] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2010] [Revised: 09/16/2010] [Accepted: 09/16/2010] [Indexed: 01/15/2023] Open
Abstract
Deep brain stimulation (DBS) surgery has been performed in over 75,000 people worldwide, and has been shown to be an effective treatment for Parkinson's disease, tremor, dystonia, epilepsy, depression, Tourette's syndrome, and obsessive compulsive disorder. We review current and emerging evidence for the role of DBS in the management of a range of neurological and psychiatric conditions, and discuss the technical and practical aspects of performing DBS surgery. In the future, evolution of DBS technology may depend on several key areas, including better scientific understanding of its underlying mechanism of action, advances in high-spatial resolution imaging and development of novel electrophysiological and neurotransmitter microsensor systems. Such developments could form the basis of an intelligent closed-loop DBS system with feedback-guided neuromodulation to optimize both electrode placement and therapeutic efficacy.
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Affiliation(s)
- Rahul S Shah
- Department of Neurological Surgery, Mayo Clinic, Rochester, MN, USA
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Marin C, Obeso J. Catechol-O-Methyltransferase Inhibitors in Preclinical Models as Adjuncts of l-Dopa Treatment. International Review of Neurobiology 2010. [DOI: 10.1016/b978-0-12-381326-8.00008-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Lee KH, Blaha CD, Garris PA, Mohseni P, Horne AE, Bennet KE, Agnesi F, Bledsoe JM, Lester DB, Kimble C, Min HK, Kim YB, Cho ZH. Evolution of Deep Brain Stimulation: Human Electrometer and Smart Devices Supporting the Next Generation of Therapy. Neuromodulation 2009; 12:85-103. [PMID: 20657744 DOI: 10.1111/j.1525-1403.2009.00199.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Deep Brain Stimulation (DBS) provides therapeutic benefit for several neuropathologies including Parkinson's disease (PD), epilepsy, chronic pain, and depression. Despite well established clinical efficacy, the mechanism(s) of DBS remains poorly understood. In this review we begin by summarizing the current understanding of the DBS mechanism. Using this knowledge as a framework, we then explore a specific hypothesis regarding DBS of the subthalamic nucleus (STN) for the treatment of PD. This hypothesis states that therapeutic benefit is provided, at least in part, by activation of surviving nigrostriatal dopaminergic neurons, subsequent striatal dopamine release, and resumption of striatal target cell control by dopamine. While highly controversial, we present preliminary data that are consistent with specific predications testing this hypothesis. We additionally propose that developing new technologies, e.g., human electrometer and closed-loop smart devices, for monitoring dopaminergic neurotransmission during STN DBS will further advance this treatment approach.
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Affiliation(s)
- Kendall H Lee
- Department of Neurosurgery and Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota
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Marin C, Aguilar E, Mengod G, Cortés R, Rodríguez-Oroz M, Obeso J. Entacapone potentiates the long-duration response but does not normalize levodopa-induced molecular changes. Neurobiol Dis 2008; 32:340-8. [DOI: 10.1016/j.nbd.2008.07.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2008] [Revised: 07/04/2008] [Accepted: 07/25/2008] [Indexed: 11/15/2022] Open
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Affiliation(s)
- George S Wilson
- Department of Chemistry, University of Kansas, Lawrence, Kansas 66045, USA.
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Riederer P, Gerlach M, Müller T, Reichmann H. Relating mode of action to clinical practice: dopaminergic agents in Parkinson's disease. Parkinsonism Relat Disord 2007; 13:466-79. [PMID: 17919963 DOI: 10.1016/j.parkreldis.2007.06.015] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2006] [Revised: 06/12/2007] [Accepted: 06/29/2007] [Indexed: 10/22/2022]
Abstract
Most treatment advances in PD have been based on restoring dopaminergic input. The development of levodopa was the first breakthrough and, since then, other compounds have been developed. Each antiparkinsonian medication has its own profile of efficacy and adverse effects, and these can largely be explained by their modes of action. As patients receive a number of different compounds, physicians should be aware of the differences of agents and understand how these differences may relate to clinical practice. This article reviews the three main classes of dopaminergic PD therapy (levodopa, monoamine oxidase inhibitors and dopamine agonists).
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Affiliation(s)
- Peter Riederer
- Klinische Neurochemie Universitätsklinik für Psychiatrie und Psychotherapie, Würzburg, Germany.
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Abstract
Parkinson's disease (PD) is one of the most frequent, chronic, progressive degenerative disorders of the CNS, characterised by altered neurotransmission of dopamine in the basal ganglia. This may result in disturbances of movement, mobility and posture symptoms, all of which cause severe disability in PD patients. There is no cure for PD. Current treatment approaches aim at symptomatic improvement with a balance of the altered neurotransmission, particularly in striatal dopaminergic neurons. Levodopa, the metabolic precursor of active dopamine, is the most effective compound in the drug treatment of PD. However, chronic exposure to levodopa and related dopaminergic agents supports an onset of movement behaviour fluctuations and dyskinesia in the long term. Dyskinesia is unwanted, sometimes excessive and causes abnormal facial, body and limb movements that appear in many PD patients who are often dependent on the overall dosage of dopaminergic substitution. This complication of anti-Parkinsonian drug therapy supports disability and reduces quality of life in PD patients and their caregivers. This review focuses on the major clinical features and knowledge on the aetiology of these treatment-associated, long-term side effects of dopaminergic drug treatment in PD. It also gives an overview of existing and potential future treatment-strategies for the management of these troublesome treatment complications that affect motor behaviour in PD patients.
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Affiliation(s)
- Thomas Müller
- Department of Neurology, St. Josef-Hospital, Ruhr University Bochum, Gudrunstrasse 56 44791 Bochum, Germany.
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Müller T, Erdmann C, Muhlack S, Bremen D, Przuntek H, Woitalla D. Inhibition of catechol-O-methyltransferase contributes to more stable levodopa plasma levels. Mov Disord 2006; 21:332-6. [PMID: 16211593 DOI: 10.1002/mds.20717] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
The short plasma half-life limits the antiparkinsonian efficacy of levodopa/carbidopa (LD/CD). Administration of LD/CD with the catechol-O-methyltransferase inhibitor entacapone in one tablet (LCE) may extend plasma half-life of LD and thus its effect on motor symptoms in patients with Parkinson's disease (PD). The objectives of this study were to monitor the motor response to a switch from LD/CD to LCE by a simultaneous performance of an instrumental motor test and rating of motor symptoms and to compare the LD plasma behavior between both conditions in terms of stability. Twenty-one treated PD patients received LD/CD and then the identical oral LD dosage of LCE within a standardized setting on 2 consecutive days. Rating better reflected the motor improvement after LD application than the instrumental test. Motor symptoms of PD patients decreased significantly more during the LCE than the LD/CD condition, probably due to significantly higher LD plasma levels and a significantly less pronounced fall of the LD concentrations following the second LD intake. Our study shows a more stable LD plasma behavior during LCE intake and accordingly a better effect on motor symptoms according to rating outcomes and motor test results to a lesser extent.
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Affiliation(s)
- Thomas Müller
- Department of Neurology, St. Josef Hospital, Ruhr University Bochum, Bochum, Germany.
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Abstract
Levodopa is the most efficacious treatment in the management of Parkinson's disease. Unfortunately, chronic use of traditional levodopa/dopa decarboxylase inhibitor formulations is associated with the development of complications, such as wearing-off and dyskinesia. In an attempt to avoid these complications, some physicians delay the introduction of levodopa or employ levodopa-sparing strategies; however, these strategies are frequently suboptimal for patients. As most patients require the superior efficacy of levodopa during the course of their disease, an appreciation of the changing response to levodopa over time and an understanding of the pharmacokinetic principles underlying the development of complications such as wearing-off is essential in the long-term management of the patient.
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Affiliation(s)
- Fabrizio Stocchi
- Department of Neurology, IRCCS San Raffaele Pisana, Via della Pisana 235, 00163, Rome, Italy.
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Marin C, Aguilar E, Obeso JA. Coadministration of entacapone with levodopa attenuates the severity of dyskinesias in hemiparkinsonian rats. Mov Disord 2006; 21:646-53. [PMID: 16437585 DOI: 10.1002/mds.20780] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Levodopa-induced dyskinesias (LIDs) have been associated with a sequence of events that includes pulsatile stimulation of dopamine receptors. The degree of nigrostriatal degeneration, the half-life of dopaminomimetic agents, and the dose of levodopa used to treat parkinsonian symptoms are factors directly correlated with the development of motor complications in Parkinson's disease patients. Long-acting agents producing continuous dopaminergic stimulation are less likely to prime for dyskinesia than short-acting drugs that produce pulsatile stimulation of dopamine receptors. Inhibition of the enzyme catechol-O-methyl transferase (COMT) by entacapone extends the half-life of levodopa and minimizes variability in plasma levodopa levels. The aim of the present study was to characterize the effect of the early administration of the COMT inhibitor entacapone in the recently described model of LIDs in rats with a nigrostriatal lesion induced by 6-hydroxydopamine (6-OHDA). Male Sprague-Dawley rats received a unilateral 6-OHDA administration in the nigrostriatal pathway. Animals were treated either with levodopa (6 mg/kg, twice at day, i.p.) plus entacapone (30 mg/kg per day, i.p.) or levodopa (6 mg/kg, twice at day, i.p.) plus vehicle for 22 consecutive days. Early administration of entacapone, in association with levodopa, induces a decrease in the severity of dyskinesia and delays their onset in hemiparkinsonian rats. All dyskinesia subtypes evaluated, such as axial, limb, and orofacial dyskinesias, have shown similar reductions. These results suggest that entacapone, by extending levodopa elimination half-life, might reduce its propensity to induce motor complications.
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Affiliation(s)
- Concepció Marin
- Laboratori de Neurologia Experimental, Fundació Clínic-Hospital Clínic, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Hospital Clínic, Barcelona, Spain.
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