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Boi L, Fisone G. Investigating affective neuropsychiatric symptoms in rodent models of Parkinson's disease. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2023; 174:119-186. [PMID: 38341228 DOI: 10.1016/bs.irn.2023.08.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/12/2024]
Abstract
Affective neuropsychiatric disorders such as depression, anxiety and apathy are among the most frequent non-motor symptoms observed in people with Parkinson's disease (PD). These conditions often emerge during the prodromal phase of the disease and are generally considered to result from neurodegenerative processes in meso-corticolimbic structures, occurring in parallel to the loss of nigrostriatal dopaminergic neurons. Depression, anxiety, and apathy are often treated with conventional medications, including selective serotonin reuptake inhibitors, tricyclic antidepressants, and dopaminergic agonists. The ability of these pharmacological interventions to consistently counteract such neuropsychiatric symptoms in PD is still relatively limited and the development of reliable experimental models represents an important tool to identify more effective treatments. This chapter provides information on rodent models of PD utilized to study these affective neuropsychiatric symptoms. Neurotoxin-based and genetic models are discussed, together with the main behavioral tests utilized to identify depression- and anxiety-like behaviors, anhedonia, and apathy. The ability of various therapeutic approaches to counteract the symptoms observed in the various models is also reviewed.
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Affiliation(s)
- Laura Boi
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Gilberto Fisone
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden.
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Goodkin K, Evering TH, Anderson AM, Ragin A, Monaco CL, Gavegnano C, Avery RJ, Rourke SB, Cysique LA, Brew BJ. The comorbidity of depression and neurocognitive disorder in persons with HIV infection: call for investigation and treatment. Front Cell Neurosci 2023; 17:1130938. [PMID: 37206666 PMCID: PMC10190964 DOI: 10.3389/fncel.2023.1130938] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Accepted: 03/07/2023] [Indexed: 05/21/2023] Open
Abstract
Depression and neurocognitive disorder continue to be the major neuropsychiatric disorders affecting persons with HIV (PWH). The prevalence of major depressive disorder is two to fourfold higher among PWH than the general population (∼6.7%). Prevalence estimates of neurocognitive disorder among PWH range from 25 to over 47% - depending upon the definition used (which is currently evolving), the size of the test battery employed, and the demographic and HIV disease characteristics of the participants included, such as age range and sex distribution. Both major depressive disorder and neurocognitive disorder also result in substantial morbidity and premature mortality. However, though anticipated to be relatively common, the comorbidity of these two disorders in PWH has not been formally studied. This is partly due to the clinical overlap of the neurocognitive symptoms of these two disorders. Both also share neurobehavioral aspects - particularly apathy - as well as an increased risk for non-adherence to antiretroviral therapy. Shared pathophysiological mechanisms potentially explain these intersecting phenotypes, including neuroinflammatory, vascular, and microbiomic, as well as neuroendocrine/neurotransmitter dynamic mechanisms. Treatment of either disorder affects the other with respect to symptom reduction as well as medication toxicity. We present a unified model for the comorbidity based upon deficits in dopaminergic transmission that occur in both major depressive disorder and HIV-associated neurocognitive disorder. Specific treatments for the comorbidity that decrease neuroinflammation and/or restore associated deficits in dopaminergic transmission may be indicated and merit study.
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Affiliation(s)
- Karl Goodkin
- Department of Psychiatry, School of Medicine, The University of Texas Rio Grande Valley, Harlingen, TX, United States
- Institute of Neuroscience, School of Medicine, The University of Texas Rio Grande Valley, Harlingen, TX, United States
| | - Teresa H. Evering
- Division of Infectious Diseases, Department of Medicine, Weill Cornell Medicine, New York, NY, United States
| | - Albert M. Anderson
- Division of Infectious Diseases, Department of Medicine, School of Medicine, Emory University, Atlanta, GA, United States
| | - Ann Ragin
- Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
| | - Cynthia L. Monaco
- Division of Infectious Diseases, Department of Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY, United States
- Department of Microbiology and Immunology, University of Rochester School of Medicine and Dentistry, Rochester, NY, United States
- Del Monte Institute of Neuroscience, University of Rochester School of Medicine and Dentistry, Rochester, NY, United States
| | - Christina Gavegnano
- Department of Pathology, Emory School of Medicine, Emory University, Atlanta, GA, United States
- Department of Pharmacology, Emory School of Medicine, Emory University, Atlanta, GA, United States
- Department of Chemical Biology, Emory School of Medicine, Emory University, Atlanta, GA, United States
- Center for the Study of Human Health, Emory College of Arts and Sciences, Emory University, Atlanta, GA, United States
- Atlanta Veteran’s Affairs Medical Center, Atlanta, GA, United States
- Center for Bioethics, Harvard Medical School, Harvard University, Boston, MA, United States
| | - Ryan J. Avery
- Division of Nuclear Medicine, Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
| | - Sean B. Rourke
- MAP Centre for Urban Health Solutions, Li Ka Shing Knowledge Institute, St. Michael’s Hospital, Toronto, ON, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada
| | - Lucette A. Cysique
- School of Psychology, Faculty of Science, University of New South Wales, Sydney, NSW, Australia
| | - Bruce J. Brew
- Department of Neurology, Faculty of Medicine, University of New South Wales, Sydney, NSW, Australia
- Department of Neurology, Faculty of Medicine, University of Notre Dame, Sydney, NSW, Australia
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The role of dopamine pharmacotherapy and addiction-like behaviors in Parkinson's disease. Prog Neuropsychopharmacol Biol Psychiatry 2020; 102:109942. [PMID: 32272129 DOI: 10.1016/j.pnpbp.2020.109942] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 03/29/2020] [Accepted: 03/31/2020] [Indexed: 12/19/2022]
Abstract
Addictions involve a spectrum of behaviors that encompass features of impulsivity and compulsivity, herein referred to as impulsive-compulsive spectrum disorders (ICSDs). The etiology of ICSDs likely involves a complex interplay among neurobiological, psychological and social risk factors. Neurobiological risk factors include the status of the neuroanatomical circuits that govern ICSDs. These circuits can be altered by disease, as well as exogenous influences such as centrally-acting pharmacologics. The 'poster child' for this scenario is Parkinson's disease (PD) medically managed by pharmacological treatments. PD is a progressive neurodegenerative disease that involves a gradual loss of dopaminergic neurons largely within nigrostriatal projections. Replacement therapy includes dopamine receptor agonists that directly activate postsynaptic dopamine receptors (bypassing the requirement for functioning presynaptic terminals). Some clinically useful dopamine agonists, e.g., pramipexole and ropinirole, exhibit high affinity for the D2/D3 receptor subtypes. These agonists provide excellent relief from PD motor symptoms, but some patients exhibit debilitating ICSD. Teasing out the neuropsychiatric contribution of PD-associated pathology from the drugs used to treat PD motor symptoms is challenging. In this review, we posit that modern clinical and preclinical research converge on the conclusion that dopamine replacement therapy can mediate addictions in PD and other neurological disorders. We provide five categories of evidences that align with this position: (i) ICSD prevalence is greater with D2/D3 receptor agonist therapy vs PD alone. (ii) Capacity of dopamine replacement therapy to produce addiction-like behaviors is independent of disease for which the therapy is being provided. (iii) ICSD-like behaviors are recapitulated in laboratory rats with and without PD-like pathology. (iv) Behavioral pathology co-varies with drug exposure. (v) ICSD Features of ICSDs are consistent with agonist pharmacology and neuroanatomical substrates of addictions. Considering the underpinnings of ICSDs in PD should not only help therapeutic decision-making in neurological disorders, but also apprise ICSDs in general.
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Bellucci G, Münte TF, Park SQ. Effects of a dopamine agonist on trusting behaviors in females. Psychopharmacology (Berl) 2020; 237:1671-1680. [PMID: 32107571 DOI: 10.1007/s00213-020-05488-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 02/14/2020] [Indexed: 12/11/2022]
Abstract
Trust is central to bonding and cooperation. In many social interactions, individuals need to trust another person exclusively on the basis of their subjective impressions of the other's trustworthiness. Such impressions can be formed from social information from faces (e.g., facial trustworthiness and attractiveness) and guide trusting behaviors via activations of dopaminergic brain regions. However, the specific dopaminergic effects on impression-based trust are to date elusive. Here, in a double-blind, placebo-controlled, within-subject design, we administrated a D2/D3 dopamine agonist (pramipexole) to 28 healthy females who subsequently played a one-shot trust game with partners of varying facial trustworthiness. Our results show that by minimizing facial attractiveness information, we could isolate the specific effects of facial trustworthiness on trust in unknown partners. Despite no modulation of trustworthiness impressions, pramipexole intake significantly impacted trusting behaviors. Notably, these effects of pramipexole on trusting behaviors interacted with participants' hormonal contraceptive use. In particular, after pramipexole intake, trust significantly decreased in hormonal contraceptive non-users. This study fills an important gap in the experimental literature on trust and its neural dynamics, unearthing the cognitive and neural modulations of trusting behaviors based on trustworthiness impressions of others.
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Affiliation(s)
- Gabriele Bellucci
- Department of Psychology I, University of Lübeck, 23562, Lübeck, Germany.
- Department of Computational Neuroscience, Max Planck Institute for Biological Cybernetics, Tübingen, Germany.
| | - Thomas F Münte
- Department of Neurology, Universitätsklinikum Schleswig-Holstein, 23538, Lübeck, Germany
- Department of Psychology II, University of Lübeck, 23562, Lübeck, Germany
| | - Soyoung Q Park
- Department of Psychology I, University of Lübeck, 23562, Lübeck, Germany
- Decision Neuroscience and Nutrition, German Institute of Human Nutrition (DIfE), Potsdam-Rehbruecke, Nuthetal, Germany
- Corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Neuroscience Research Center, Charité-Universitätsmedizin Berlin, 10117, Berlin, Germany
- Deutsches Zentrum für Diabetes, 85764, Neuherberg, Germany
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5
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Vachez Y, Carcenac C, Magnard R, Kerkerian‐Le Goff L, Salin P, Savasta M, Carnicella S, Boulet S. Subthalamic Nucleus Stimulation Impairs Motivation: Implication for Apathy in Parkinson's Disease. Mov Disord 2020; 35:616-628. [DOI: 10.1002/mds.27953] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 11/13/2019] [Accepted: 11/25/2019] [Indexed: 12/25/2022] Open
Affiliation(s)
- Yvan Vachez
- Inserm U1216 Grenoble France
- Univ. Grenoble Alpes, Grenoble Institut des Neurosciences, GIN Grenoble France
| | - Carole Carcenac
- Inserm U1216 Grenoble France
- Univ. Grenoble Alpes, Grenoble Institut des Neurosciences, GIN Grenoble France
| | - Robin Magnard
- Inserm U1216 Grenoble France
- Univ. Grenoble Alpes, Grenoble Institut des Neurosciences, GIN Grenoble France
| | | | | | - Marc Savasta
- Inserm U1216 Grenoble France
- Univ. Grenoble Alpes, Grenoble Institut des Neurosciences, GIN Grenoble France
| | - Sebastien Carnicella
- Inserm U1216 Grenoble France
- Univ. Grenoble Alpes, Grenoble Institut des Neurosciences, GIN Grenoble France
| | - Sabrina Boulet
- Inserm U1216 Grenoble France
- Univ. Grenoble Alpes, Grenoble Institut des Neurosciences, GIN Grenoble France
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6
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Bellucci G, Münte TF, Park SQ. Resting-state dynamics as a neuromarker of dopamine administration in healthy female adults. J Psychopharmacol 2019; 33:955-964. [PMID: 31246145 DOI: 10.1177/0269881119855983] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
BACKGROUND Different neuromarkers of people's emotions, personality traits and behavioural performance have recently been identified. However, not much attention has been devoted to neuromarkers of neural responsiveness to drug administration. AIMS We investigated the predictive neuromarkers of acute dopamine (DA) administration. METHODS In a double-blind, within-subject study, we administrated a DA agonist (pramipexole) or placebo to 27 healthy female subjects. Using multivariate classification and prediction analyses, we examined whether dopaminergic modulations of task-free resting-state brain dynamics predict individual differences in pramipexole's modulation of facial attractiveness evaluations. RESULTS Our results demonstrate that pramipexole's effects on brain dynamics could be successfully discriminated from resting-state functional connectivity (accuracy: 78.9%; p < 0.0001). On the behavioural level, pramipexole increased facial attractiveness evaluations (t(39) = 4.44; p < 0.0001). In particular, pramipexole administration enhanced connectivity strength of the cinguloopercular network (t(23) = 3.29; p = 0.003) and increased brain signal variability in subcortical and prefrontal brain areas (t(13) = 3.05, p = 0.009). Importantly, multivariate predictive models reveal that pramipexole-dependent modulation of resting-state dynamics predicted the increase of facial attractiveness evaluations after pramipexole (connectivity strength: standardized mean squared error, smse = 0.65; p = 0.0007; brain signal variability: smse = 0.94, p = 0.015). CONCLUSION These results demonstrate that modulations of resting-state brain dynamics induced by a DA agonist predict drug-related effects on evaluation processes, providing a neuromarker of the neural responsiveness of specific brain networks to DA administration.
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Affiliation(s)
- Gabriele Bellucci
- 1 Department of Psychology I, University of Lübeck, Lübeck, Germany.,2 Decision Neuroscience and Nutrition, German Institute of Human Nutrition (DIfE), Nuthetal, Germany
| | - Thomas F Münte
- 3 Department of Neurology, Universitätsklinikum Schleswig-Holstein, Lübeck, Germany.,4 Department of Psychology II, University of Lübeck, Lübeck, Germany
| | - Soyoung Q Park
- 1 Department of Psychology I, University of Lübeck, Lübeck, Germany.,2 Decision Neuroscience and Nutrition, German Institute of Human Nutrition (DIfE), Nuthetal, Germany.,5 Charité-Universitätsmedizin Berlin, Corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Neuroscience Research Center, Berlin, Germany
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Napier TC, Persons AL. Pharmacological insights into impulsive-compulsive spectrum disorders associated with dopaminergic therapy. Eur J Neurosci 2018; 50:2492-2502. [PMID: 30269390 DOI: 10.1111/ejn.14177] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 09/13/2018] [Accepted: 09/14/2018] [Indexed: 12/31/2022]
Abstract
Impulsive-compulsive spectrum disorders are associated with dopamine agonist therapy in some patients. These untoward outcomes occur with direct-acting, full and partial agonists at D2 dopamine family receptors. The disorders typically emerge during chronic treatment, and exhibit common features that are independent of the neurological or psychiatric pathology for which the initial therapy was indicated. It is well-documented that the brain is 'plastic', changing in response to alterations to internal factors (e.g., disease processes), as well as external factors (e.g., therapies). The complexities of these clinical scenarios have eluded a clear depiction of the neurobiology for impulsive-compulsive spectrum disorders and engendered considerable debate regarding the mechanistic underpinnings of the disorders. In this opinion, we use pharmacological concepts related to homeostatic compensation subsequent to chronic receptor activation to provide a unifying construct. This construct helps explain the occurrence of impulsive-compulsive spectrum disorders across disease states, and during therapy with full and partial agonists.
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Affiliation(s)
- T Celeste Napier
- Department of Psychiatry, Rush University Medical Center, Chicago, IL, USA.,Center for Compulsive Behavior and Addiction, Rush University Medical Center, Chicago, IL, USA
| | - Amanda L Persons
- Department of Psychiatry, Rush University Medical Center, Chicago, IL, USA.,Center for Compulsive Behavior and Addiction, Rush University Medical Center, Chicago, IL, USA.,Department of Physician Assistant Studies, Rush University Medical Center, Chicago, IL, USA
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Custodio N, Alva-Diaz C, Morán-Mariños C, Mejía-Rojas K, Lira D, Montesinos R, Herrera-Pérez E, Castro-Suárez S, Bardales Y. Factors associated with depression in patients with Parkinson's disease A multicenter study in Lima, Peru. Dement Neuropsychol 2018; 12:292-298. [PMID: 30425793 PMCID: PMC6200150 DOI: 10.1590/1980-57642018dn12-030010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2018] [Accepted: 06/25/2018] [Indexed: 11/22/2022] Open
Abstract
The diagnosis and treatment of depression in patients with Parkinson's disease (PD) is inadequate, often contributing to a reduced quality of life, rapid disease progression, higher cognitive impairment, and an increased burden of care for family members of patients with PD. OBJECTIVE To determine the factors associated with depression in PD and to examine the frequency of depressive symptoms among patients with PD. METHODS This study was an observational, analytical, multicenter study of a cross-sectional cohort, conducted between July 2016 and May 2017. PD patients were recruited from neurology clinics in Lima, Peru. All statistical analyses were performed using descriptive statistics. Bivariate and multivariate logistic regression analyses were calculated using STATA. RESULTS Out of 124 patients (average age: 68.7 years; 58% males) included in the study 60.5% (75/124) presented with symptoms of depression; only 20% (25/124) received antidepressants. Factors associated with depression in PD included: unemployment, falls, freezing of gait, involuntary movements micrographia, stooped posture, hyposmia, movement disorders in sleep, rapid disease progression, and the use of MAOIs. Furthermore, statistically significant differences were found in disease duration, UPDRS and MMSE scores, Hoehn and Yahr (HY) stage, and length of time taking L-dopa between PD patients with and without depressive symptoms. CONCLUSION Factors associated with depressive symptoms in patients with PD were hyposmia, rapid progression of the disease, the use of L-dopa, and use of MAOIs. The frequency of depressive symptoms in patients with PD is high; early diagnosis and prompt treatment are needed to improve their quality of life and the family environment.
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Affiliation(s)
- Nilton Custodio
- Department of Neurology, Peruvian Institute of Neurosciences, Lima, Peru
- Diagnostic Unit for Cognitive Impairment and Dementia Prevention, International Clinic, Lima, Peru
- Research Unit, Peruvian Institute of Neurosciences, Lima, Peru
- Rehabilitation Medicine Department, Peruvian Institute of Neurosciences, Lima, Peru
- Department of Neurology of Human Behavior. National Institute of Neurological Sciences. Lima, Peru
| | - Carlos Alva-Diaz
- Research Unit, Peruvian Institute of Neurosciences, Lima, Peru
- Clinical and Healthcare Efficiency Network (REDECS). Lima, Peru
- Neurology Department, Hospital Nacional Daniel Alcides Carrión, Callao, Peru
- Research Center OADI, Hospital Nacional Daniel Alcides Carrión, Callao, Peru
| | - Cristian Morán-Mariños
- Research Unit, Peruvian Institute of Neurosciences, Lima, Peru
- Clinical and Healthcare Efficiency Network (REDECS). Lima, Peru
- Neurology Department, Hospital Nacional Daniel Alcides Carrión, Callao, Peru
- Peruvian Student Medical Scientific Society, Universidad Privada San Juan Bautista (SOCIEM - UPSJB). Lima, Peru
| | - Koni Mejía-Rojas
- Research Unit, Peruvian Institute of Neurosciences, Lima, Peru
- Neurology Department, Hospital Nacional Daniel Alcides Carrión, Callao, Peru
| | - David Lira
- Department of Neurology, Peruvian Institute of Neurosciences, Lima, Peru
- Diagnostic Unit for Cognitive Impairment and Dementia Prevention, International Clinic, Lima, Peru
- Research Unit, Peruvian Institute of Neurosciences, Lima, Peru
- Research and Teaching Unit. International Clinic. Lima, Peru
- Department of Neurology, International Clinic. Lima, Peru
| | - Rosa Montesinos
- Diagnostic Unit for Cognitive Impairment and Dementia Prevention, International Clinic, Lima, Peru
- Research Unit, Peruvian Institute of Neurosciences, Lima, Peru
- Rehabilitation Medicine Department, Peruvian Institute of Neurosciences, Lima, Peru
- Research and Teaching Unit. International Clinic. Lima, Peru
| | - Eder Herrera-Pérez
- Diagnostic Unit for Cognitive Impairment and Dementia Prevention, International Clinic, Lima, Peru
- Research Unit, Peruvian Institute of Neurosciences, Lima, Peru
- Research and Teaching Unit. International Clinic. Lima, Peru
| | - Sheila Castro-Suárez
- Department of Neurology, Peruvian Institute of Neurosciences, Lima, Peru
- Research Unit, Peruvian Institute of Neurosciences, Lima, Peru
- Rehabilitation Medicine Department, Peruvian Institute of Neurosciences, Lima, Peru
- Department of Neurology of Human Behavior. National Institute of Neurological Sciences. Lima, Peru
- Department of Neurology, International Clinic. Lima, Peru
| | - Yadira Bardales
- Diagnostic Unit for Cognitive Impairment and Dementia Prevention, International Clinic, Lima, Peru
- Research Unit, Peruvian Institute of Neurosciences, Lima, Peru
- Research and Teaching Unit. International Clinic. Lima, Peru
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Stark AJ, Smith CT, Petersen KJ, Trujillo P, van Wouwe NC, Donahue MJ, Kessler RM, Deutch AY, Zald DH, Claassen DO. [ 18F]fallypride characterization of striatal and extrastriatal D 2/3 receptors in Parkinson's disease. Neuroimage Clin 2018; 18:433-442. [PMID: 29541577 PMCID: PMC5849871 DOI: 10.1016/j.nicl.2018.02.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 01/15/2018] [Accepted: 02/07/2018] [Indexed: 12/11/2022]
Abstract
Parkinson's disease (PD) is characterized by widespread degeneration of monoaminergic (especially dopaminergic) networks, manifesting with a number of both motor and non-motor symptoms. Regional alterations to dopamine D2/3 receptors in PD patients are documented in striatal and some extrastriatal areas, and medications that target D2/3 receptors can improve motor and non-motor symptoms. However, data regarding the combined pattern of D2/3 receptor binding in both striatal and extrastriatal regions in PD are limited. We studied 35 PD patients off-medication and 31 age- and sex-matched healthy controls (HCs) using PET imaging with [18F]fallypride, a high affinity D2/3 receptor ligand, to measure striatal and extrastriatal D2/3 nondisplaceable binding potential (BPND). PD patients completed PET imaging in the off medication state, and motor severity was concurrently assessed. Voxel-wise evaluation between groups revealed significant BPND reductions in PD patients in striatal and several extrastriatal regions, including the locus coeruleus and mesotemporal cortex. A region-of-interest (ROI) based approach quantified differences in dopamine D2/3 receptors, where reduced BPND was noted in the globus pallidus, caudate, amygdala, hippocampus, ventral midbrain, and thalamus of PD patients relative to HC subjects. Motor severity positively correlated with D2/3 receptor density in the putamen and globus pallidus. These findings support the hypothesis that abnormal D2/3 expression occurs in regions related to both the motor and non-motor symptoms of PD, including areas richly invested with noradrenergic neurons.
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Affiliation(s)
- Adam J Stark
- Neurology, Vanderbilt University Medical Center, Nashville, TN, United States
| | | | - Kalen J Petersen
- Neurology, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Paula Trujillo
- Neurology, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Nelleke C van Wouwe
- Neurology, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Manus J Donahue
- Neurology, Vanderbilt University Medical Center, Nashville, TN, United States; Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, United States; Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Robert M Kessler
- Radiology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Ariel Y Deutch
- Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, TN, United States; Pharmacology, Vanderbilt University, Nashville, TN, United States
| | - David H Zald
- Psychology, Vanderbilt University, Nashville, TN, United States; Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Daniel O Claassen
- Neurology, Vanderbilt University Medical Center, Nashville, TN, United States.
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Cardon-Dunbar A, Robertson T, Roberts MS, Isbister GK. Pramipexole Overdose Associated with Visual Hallucinations, Agitation and Myoclonus. J Med Toxicol 2017; 13:343-346. [PMID: 28547577 DOI: 10.1007/s13181-017-0615-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2017] [Revised: 04/16/2017] [Accepted: 04/25/2017] [Indexed: 11/25/2022] Open
Abstract
INTRODUCTION Pramipexole is a dopamine D2 receptor agonist used to treat idiopathic Parkinson's disease and primary restless legs syndrome. There is limited information on pramipexole overdose. CASE REPORT A 59-year-old male ingested 3 mg pramipexole, 2250 mg venlafaxine, 360 mg mirtazapine, with suicidal intent. He presented alert, had normal vital observations and normal pupillary reflexes. He was mildly agitated, reported visual hallucinations and was given 5 mg diazepam. He had a mildly elevated lactate of 1.7 mmol/L, but otherwise normal laboratory investigations. Overnight, he remained agitated with visual hallucinations and developed myoclonus while awake. He had increasing difficulty passing urine on a background of mild chronic urinary retention. On review, 14 h post-ingestion, he was hypervigilant, jittery and mildly agitated. He had pressured speech and difficulty focusing on questioning. He had a heart rate of 110 bpm, but had an otherwise normal examination, with no clonus or extrapyramidal effects. He was unable to mobilize due to dizziness and ataxia. Over the next few hours, he improved, the visual hallucinations and agitation resolved and he mobilized independently. Pramipexole was measured with liquid chromatography mass spectrometry. The initial plasma pramipexole concentration was 34.2 ng/mL (therapeutic range 0.2 to 7 ng/mL), 9 h post-overdose. Concentration time data fitted a one-compartment model with an estimated elimination half-life of 18 h. DISCUSSION Pramipexole overdose with hallucination, agitation, and myoclonus is consistent with adverse effects reported with therapeutic toxicity, but mirtazapine and venlafaxine may have contributed. Pramipexole concentrations exceeded the therapeutic range for over 24 h. With the increasing use of pramipexole in restless legs syndrome, adult overdoses may become more common.
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Affiliation(s)
- Adeline Cardon-Dunbar
- Department of Clinical Toxicology and Pharmacology, Calvary Mater Newcastle, Newcastle, New South Wales, Australia
| | - Tom Robertson
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, Australia
| | - Michael S Roberts
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, Australia.,Therapeutics Research Centre, University of Queensland, Brisbane, Queensland, Australia
| | - Geoffrey K Isbister
- Department of Clinical Toxicology and Pharmacology, Calvary Mater Newcastle, Newcastle, New South Wales, Australia. .,Clinical Toxicology Research Group, University of Newcastle, Newcastle, New South Wales, Australia.
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11
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Williams LM. Defining biotypes for depression and anxiety based on large-scale circuit dysfunction: a theoretical review of the evidence and future directions for clinical translation. Depress Anxiety 2017; 34:9-24. [PMID: 27653321 PMCID: PMC5702265 DOI: 10.1002/da.22556] [Citation(s) in RCA: 161] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Revised: 07/28/2016] [Accepted: 08/15/2016] [Indexed: 01/23/2023] Open
Abstract
Complex emotional, cognitive and self-reflective functions rely on the activation and connectivity of large-scale neural circuits. These circuits offer a relevant scale of focus for conceptualizing a taxonomy for depression and anxiety based on specific profiles (or biotypes) of neural circuit dysfunction. Here, the theoretical review first outlines the current consensus as to what constitutes the organization of large-scale circuits in the human brain identified using parcellation and meta-analysis. The focus is on neural circuits implicated in resting reflection (default mode), detection of "salience," affective processing ("threat" and "reward"), "attention," and "cognitive control." Next, the current evidence regarding which type of dysfunctions in these circuits characterize depression and anxiety disorders is reviewed, with an emphasis on published meta-analyses and reviews of circuit dysfunctions that have been identified in at least two well-powered case:control studies. Grounded in the review of these topics, a conceptual framework is proposed for considering neural circuit-defined "biotypes." In this framework, biotypes are defined by profiles of extent of dysfunction on each large-scale circuit. The clinical implications of a biotype approach for guiding classification and treatment of depression and anxiety is considered. Future research directions will develop the validity and clinical utility of a neural circuit biotype model that spans diagnostic categories and helps to translate neuroscience into clinical practice in the real world.
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Affiliation(s)
- Leanne M Williams
- Corresponding author: Leanne M Williams, PhD, Department of Psychiatry and Behavioral Sciences, Stanford University, 401 Quarry Road, California, 94134-5717, , Phone: 650 723 3579
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Hu T, Yang F, Jiang T, Chen W, Zhang J, Li J, Jiang X, Shen J. Synthesis of Impurities of Pramipexole Dihydrochloride. Org Process Res Dev 2016. [DOI: 10.1021/acs.oprd.6b00182] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Tianwen Hu
- CAS
Key Laboratory of Receptor Research, Drug Discovery and Design Center, Shanghai Institute of Materia Medica, Chinese Academy of Sciences (CAS), 555
Zuchongzhi Road, Shanghai 201203, China
- University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China
| | - Feipu Yang
- CAS
Key Laboratory of Receptor Research, Drug Discovery and Design Center, Shanghai Institute of Materia Medica, Chinese Academy of Sciences (CAS), 555
Zuchongzhi Road, Shanghai 201203, China
- University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China
| | - Tao Jiang
- CAS
Key Laboratory of Receptor Research, Drug Discovery and Design Center, Shanghai Institute of Materia Medica, Chinese Academy of Sciences (CAS), 555
Zuchongzhi Road, Shanghai 201203, China
- University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China
| | - Weiming Chen
- Topharman Shanghai Co. Ltd., Shanghai 201209, China
| | - Jian Zhang
- Topharman Shanghai Co. Ltd., Shanghai 201209, China
| | - Jianfeng Li
- CAS
Key Laboratory of Receptor Research, Drug Discovery and Design Center, Shanghai Institute of Materia Medica, Chinese Academy of Sciences (CAS), 555
Zuchongzhi Road, Shanghai 201203, China
| | - Xiangrui Jiang
- CAS
Key Laboratory of Receptor Research, Drug Discovery and Design Center, Shanghai Institute of Materia Medica, Chinese Academy of Sciences (CAS), 555
Zuchongzhi Road, Shanghai 201203, China
| | - Jingshan Shen
- CAS
Key Laboratory of Receptor Research, Drug Discovery and Design Center, Shanghai Institute of Materia Medica, Chinese Academy of Sciences (CAS), 555
Zuchongzhi Road, Shanghai 201203, China
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Deutschländer A, la Fougère C, Boetzel K, Albert NL, Gildehaus FJ, Bartenstein P, Xiong G, Cumming P. Occupancy of pramipexole (Sifrol) at cerebral dopamine D2/3 receptors in Parkinson's disease patients. NEUROIMAGE-CLINICAL 2016; 12:41-6. [PMID: 27408789 PMCID: PMC4925448 DOI: 10.1016/j.nicl.2016.06.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Revised: 06/07/2016] [Accepted: 06/08/2016] [Indexed: 11/19/2022]
Abstract
Whereas positron emission tomography (PET) with the antagonist ligand [18F]fallypride reveals the composite of dopamine D2 and D3 receptors in brain, treatment of Parkinson's disease (PD) patients with the D3-prefering agonist pramipexole should result in preferential occupancy in the nucleus accumbens, where the D3-subtype is most abundant. To test this prediction we obtained pairs of [18F]fallypride PET recordings in a group of nine PD patients, first in a condition of treatment as usual with pramipexole (ON-Sifrol; 3 × 0.7 mg p.d.), and again at a later date, after withholding pramipexole 48–72 h (OFF-Sifrol); in that condition the serum pramipexole concentration had declined by 90% and prolactin levels had increased four-fold, in conjunction with a small but significant worsening of PD motor symptoms. Exploratory comparison with historical control material showed 14% higher dopamine D2/3 availability in the more-affected putamen of patients OFF medication. On-Sifrol there was significant (p ˂ 0.01) occupancy at [18F]fallypride binding sites in globus pallidus (8%) thalamus (9%) and substantia nigra (19%), as well as marginally significant occupancy in frontal and temporal cortex of patients. Contrary to expectation, comparison of ON- and OFF-Sifrol results did not reveal any discernible occupancy in nucleus accumbens, or elsewhere in the extended striatum; present methods should be sensitive to a 10% change in dopamine D2/3 receptor availability in striatum; the significant findings elsewhere in the basal ganglia and in cerebral cortex are consistent with a predominance of D3 receptors in those structures, especially in substantia nigra, and imply that therapeutic effects of pramipexole may be obtained at sites outside the extended striatum. Fallypride PET recordings in nine PD patients, scanned on- and off medication with pramipexole No occupancy in the striatum, despite improved motor symptoms Substantial occupancy in substantia nigra, thalamus and globus pallidus
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Affiliation(s)
| | | | - Kai Boetzel
- Department of Neurology, Ludwig-Maximilians University of Munich, Germany
| | - Nathalie L Albert
- Department of Nuclear Medicine, Ludwig-Maximilians University of Munich, Germany
| | | | - Peter Bartenstein
- Department of Nuclear Medicine, Ludwig-Maximilians University of Munich, Germany
| | - Guoming Xiong
- Department of Nuclear Medicine, Ludwig-Maximilians University of Munich, Germany
| | - Paul Cumming
- Department of Neuropsychiatry and Psychosomatic Medicine, Rikshospitalet, University of Oslo, Oslo, Norway; School of Psychology and Counselling, Institute of Health and Biomedical Innovation, Faculty of Health, Queensland University of Technology, QIMR Berghofer Medical Research Institute, Brisbane, Australia
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Roberts P, Spiros A, Geerts H. A Humanized Clinically Calibrated Quantitative Systems Pharmacology Model for Hypokinetic Motor Symptoms in Parkinson's Disease. Front Pharmacol 2016; 7:6. [PMID: 26869923 PMCID: PMC4735425 DOI: 10.3389/fphar.2016.00006] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 01/11/2016] [Indexed: 01/15/2023] Open
Abstract
The current treatment of Parkinson’s disease with dopamine-centric approaches such as L-DOPA and dopamine agonists, although very successful, is in need of alternative treatment strategies, both in terms of disease modification and symptom management. Various non-dopaminergic treatment approaches did not result in a clear clinical benefit, despite showing a clear effect in preclinical animal models. In addition, polypharmacy is common, sometimes leading to unintended effects on non-motor cognitive and psychiatric symptoms. To explore novel targets for symptomatic treatment and possible synergistic pharmacodynamic effects between different drugs, we developed a computer-based Quantitative Systems Pharmacology (QSP) platform of the closed cortico-striatal-thalamic-cortical basal ganglia loop of the dorsal motor circuit. This mechanism-based simulation platform is based on the known neuro-anatomy and neurophysiology of the basal ganglia and explicitly incorporates domain expertise in a formalized way. The calculated beta/gamma power ratio of the local field potential in the subthalamic nucleus correlates well (R2 = 0.71) with clinically observed extra-pyramidal symptoms triggered by antipsychotics during schizophrenia treatment (43 drug-dose combinations). When incorporating Parkinsonian (PD) pathology and reported compensatory changes, the computer model suggests a major increase in b/g ratio (corresponding to bradykinesia and rigidity) from a dopamine depletion of 70% onward. The correlation between the outcome of the QSP model and the reported changes in UPDRS III Motor Part for 22 placebo-normalized drug-dose combinations is R2 = 0.84. The model also correctly recapitulates the lack of clinical benefit for perampanel, MK-0567 and flupirtine and offers a hypothesis for the translational disconnect. Finally, using human PET imaging studies with placebo response, the computer model predicts well the placebo response for chronic treatment, but not for acute treatment in PD.
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Affiliation(s)
- Patrick Roberts
- In Silico BiosciencesBerwyn, PA, USA; Washington State UniversityVancouver, WA, USA
| | | | - Hugo Geerts
- In Silico BiosciencesBerwyn, PA, USA; Perelman School of Medicine, University of PennsylvaniaPhiladelphia, PA, USA
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Barone P, Santangelo G, Morgante L, Onofrj M, Meco G, Abbruzzese G, Bonuccelli U, Cossu G, Pezzoli G, Stanzione P, Lopiano L, Antonini A, Tinazzi M. A randomized clinical trial to evaluate the effects of rasagiline on depressive symptoms in non-demented Parkinson's disease patients. Eur J Neurol 2015; 22:1184-91. [PMID: 25962410 PMCID: PMC4676931 DOI: 10.1111/ene.12724] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 02/26/2015] [Indexed: 02/02/2023]
Abstract
BACKGROUND AND PURPOSE Depressed mood is a common psychiatric problem associated with Parkinson's disease (PD), and studies have suggested a benefit of rasagiline treatment. METHODS ACCORDO (see the ) was a 12-week, double-blind, placebo-controlled trial to evaluate the effects of rasagiline 1 mg/day on depressive symptoms and cognition in non-demented PD patients with depressive symptoms. The primary efficacy variable was the change from baseline to week 12 in depressive symptoms measured by the Beck Depression Inventory (BDI-IA) total score. Secondary outcomes included change from baseline to week 12 in cognitive function as assessed by a comprehensive neuropsychological battery; Parkinson's disease quality of life questionnaire (PDQ-39) scores; Apathy Scale scores; and Unified Parkinson's Disease Rating Scale (UPDRS) subscores. RESULTS One hundred and twenty-three patients were randomized. At week 12 there was no significant difference between groups for the reduction in total BDI-IA score (primary efficacy variable). However, analysis at week 4 did show a significant difference in favour of rasagiline (marginal means difference ± SE: rasagiline -5.46 ± 0.73 vs. placebo -3.22 ± 0.67; P = 0.026). There were no significant differences between groups on any cognitive test. Rasagiline significantly improved UPDRS Parts I (P = 0.03) and II (P = 0.003) scores versus placebo at week 12. Post hoc analyses showed the statistical superiority of rasagiline versus placebo in the UPDRS Part I depression item (P = 0.04) and PDQ-39 mobility (P = 0.007) and cognition domains (P = 0.026). CONCLUSIONS Treatment with rasagiline did not have significant effects versus placebo on depressive symptoms or cognition in PD patients with moderate depressive symptoms. Although limited by lack of correction for multiple comparisons, post hoc analyses signalled some improvement in patient-rated cognitive and depression outcomes.
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Affiliation(s)
- P Barone
- University of Salerno, Baronissi, Italy
| | | | | | - M Onofrj
- University of Chieti-Pescara, Chieti, Italy
| | - G Meco
- 'Sapienza' University of Rome, Rome, Italy
| | | | | | | | | | | | | | - A Antonini
- IRCCS Ospedale San Camillo, Venice, Italy
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Silindir M, Ozer AY. The benefits of pramipexole selection in the treatment of Parkinson's disease. Neurol Sci 2014; 35:1505-11. [PMID: 25038745 DOI: 10.1007/s10072-014-1891-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Accepted: 07/14/2014] [Indexed: 12/21/2022]
Abstract
Levodopa administration as a gold standard in Parkinson's disease (PD) treatment is very valuable, however, long-term administration may cause some motor complications such as abnormal unintended movements and shortening response to each dose (wearing off phenomenon). Dopamine agonists were developed to reduce duration of immobile off periods and dependence to levodopa for improving motor impairments (Clarke et al., Cochrane Libr 1:1-23, 2000). Pramipexole is one of these nonergot dopamine agonists with high relative in vitro specificity and full intrinsic activity at D2 subfamily of dopamine receptors, with a higher binding affinity to D3 than to D4 or D2 receptor subtypes (Piercey, Clin Neuropharmacol 21:141-151, 1998). It can be advantageously administered as monotherapy or adjunctive therapy to levodopa to decrease side effects and increase effectiveness in both early and advanced PD treatment.
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Affiliation(s)
- Mine Silindir
- Department of Radiopharmacy, Faculty of Pharmacy, Hacettepe University, 06100, Ankara, Turkey,
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Brichta L, Greengard P, Flajolet M. Advances in the pharmacological treatment of Parkinson's disease: targeting neurotransmitter systems. Trends Neurosci 2013; 36:543-54. [PMID: 23876424 DOI: 10.1016/j.tins.2013.06.003] [Citation(s) in RCA: 155] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2013] [Revised: 06/06/2013] [Accepted: 06/13/2013] [Indexed: 01/11/2023]
Abstract
For several decades, the dopamine precursor levodopa has been the primary therapy for Parkinson's disease (PD). However, not all of the motor and non-motor features of PD can be attributed solely to dopaminergic dysfunction. Recent clinical and preclinical advances provide a basis for the identification of additional innovative therapeutic options to improve the management of the disease. Novel pharmacological strategies must be optimized for PD by: (i) targeting disturbances of the serotonergic, noradrenergic, glutamatergic, GABAergic, and cholinergic systems in addition to the dopaminergic system, and (ii) characterizing alterations in the levels of neurotransmitter receptors and transporters that are associated with the various manifestations of the disease.
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Affiliation(s)
- Lars Brichta
- Laboratory of Molecular and Cellular Neuroscience, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA.
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Bet PM, Franken LGW, Klumpers UMH. Could pramipexole induce acute mania? A case report. Bipolar Disord 2013; 15:446-8. [PMID: 23581392 DOI: 10.1111/bdi.12067] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Accepted: 03/04/2012] [Indexed: 01/11/2023]
Abstract
OBJECTIVE In patients with bipolar disorder, olanzapine is commonly used to prevent episodes of acute mania. The drug pramipexole can, in theory, undermine the protective effect of olanzapine. Olanzapine is a dopamine D2 receptor antagonist and pramipexole is a mixed dopamine D2 /D3 receptor agonist. These drugs may therefore theoretically counteract their pharmacological effects. To date, there are no known cases in the literature where this interaction has been described. METHODS We report on a case where a patient with bipolar disorder developed mania after taking pramipexole in combination with olanzapine, and describe the pharmacological background of this interaction. RESULTS A patient with bipolar I disorder was hospitalized with a manic episode characterized by agitation and insomnia after taking pramipexole for restless leg syndrome (RLS) in combination with olanzapine. Co-medication, i.e., lithium and mirtazapine, and other circumstances are not likely to have contributed to this effect. CONCLUSION There is a probable interaction between pramipexole and olanzapine, where pramipexole undermines the protective effect of olanzapine, provoking an episode of acute mania and hospitalization. This interaction is of clinical importance since pramipexole is the treatment of choice for RLS, a condition often seen in end-stage renal disease, and has also been investigated as an antidepressant therapy in patients with bipolar disorder.
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Affiliation(s)
- Pierre M Bet
- Departments of Clinical Pharmacology and Pharmacy, Amsterdam, The Netherlands
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Nagy H, Levy-Gigi E, Somlai Z, Takáts A, Bereczki D, Kéri S. The effect of dopamine agonists on adaptive and aberrant salience in Parkinson's disease. Neuropsychopharmacology 2012; 37:950-8. [PMID: 22089321 PMCID: PMC3280658 DOI: 10.1038/npp.2011.278] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Clinical evidence suggests that after initiation of dopaminergic medications some patients with Parkinson's disease (PD) develop psychotic symptoms, such as hallucinations and delusions. Here, we tested the hypothesis that the neurocognitive basis of this phenomenon can be defined as the formation of arbitrary and illusory associations between conditioned stimuli and reward signals, called aberrant salience. Young, never-medicated PD patients and matched controls were assessed on a speeded reaction time task in which the probe stimulus was preceded by conditioned stimuli that could signal monetary reward by color or shape. The patients and controls were re-evaluated after 12 weeks during which the patients received a dopamine agonist (pramipexole or ropinirole). Results indicated that dopamine agonists increased both adaptive and aberrant salience in PD patients, that is, formation of real and illusory associations between conditioned stimuli and reward, respectively. This effect was present when associations were assessed by means of faster responding after conditioned stimuli signaling reward (implicit salience) and overt rating of stimulus-reward links (explicit salience). However, unusual feelings and experiences, which are subclinical manifestations of psychotic-like symptoms, were specifically related to irrelevant and illusory stimulus-reward associations (aberrant salience) in PD patients receiving dopamine agonists. The learning of relevant and real stimulus-reward associations (adaptive salience) was not related to unusual experiences. These results suggest that dopamine agonists may increase psychotic-like experiences in young patients with PD, possibly by facilitating dopaminergic transmission in the ventral striatum, which results in aberrant associations between conditioned stimuli and reward.
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Affiliation(s)
- Helga Nagy
- Department of Neurology, Semmelweis University, Budapest, Hungary,National Institute for Medical Rehabilitation, Budapest, Hungary
| | - Einat Levy-Gigi
- Center for Molecular and Behavioral Neuroscience, Rutgers University, Newark, NJ, USA
| | - Zsuzsanna Somlai
- Department of Psychiatry, Semmelweis University, Budapest, Hungary
| | - Annamária Takáts
- Department of Neurology, Semmelweis University, Budapest, Hungary
| | - Dániel Bereczki
- Department of Neurology, Semmelweis University, Budapest, Hungary
| | - Szabolcs Kéri
- Faculty of Medicine, Department of Physiology, University of Szeged, Szeged, Hungary,National Psychiatry Center, Budapest, Hungary,Department of Physiology, University of Szeged, Dóm sq. 10, Szeged H6720, Hungary, Tel: +36-20-448-3530, Fax: +36-62-545-842, E-mail: or
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