Intrinsic motivation in patients with Parkinson’s disease: a neuropsychological investigation of curiosity using dopamine transporter imaging

AbstractBoth intrinsic and extrinsic motivation are believed to involve brain regions that are innervated by the dopaminergic pathway. Although dopaminergic neurons in the midbrain deteriorate in Parkinson’s disease (PD), it remains unclear whether intrinsic motivation is impaired in PD patients. To address this issue, we investigated intrinsic motivation in PD patients using a task designed to assess the “Pandora effect,” which constitutes a curiosity for resolving uncertainty, even if this curiosity is likely to result in negative consequences. Twenty-seven PD patients and 27 age-matched healthy controls (HCs) completed a curiosity task in which they were required to decide either to view or skip negative pictures (e.g., snakes, spiders) and an examination battery that included the Mini-Mental State Examination, a verbal fluency test, the Trail Making Test, 10-word recall tests, and questionnaires for behavioral inhibition/activation and depression. DaTSCAN images to assess the distribution of dopamine transporters in the striatum were acquired only from PD patients. The results revealed that PD patients, relative to the HCs, viewed the pictures less frequently under both the certain and uncertain conditions. However, both the PD patients and HCs viewed the pictures at a higher frequency under the uncertain condition than under the certain condition. In the PD patients, the proportion of pictures viewed under the certain condition was positively correlated with the distribution of dopamine transporters in the striatum. These results suggest that despite the overall decreasing level of interest in viewing negative pictures, the motivation to resolve uncertainty is relatively intact in PD patients.

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Comparison Trail Making Test between individuals with Parkinson’s disease and health controls: Suggestions of cutoff point.

Psychology & Neuroscience ◽

10.1037/pne0000076 ◽

2017 ◽

Vol 10 (1) ◽

pp. 77-82 ◽

Cited By ~ 3

Author(s):

Maira Rozenfeld Olchik ◽

Marciéle Ghisi ◽

Amanda Manera Freiry ◽

Annelise Ayres ◽

Artur Francisco Shumacher Schuh ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Cutoff Point ◽

Trail Making Test ◽

Trail Making

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Neuroinflammation and protein pathology in Parkinson’s disease dementia

Acta Neuropathologica Communications ◽

10.1186/s40478-020-01083-5 ◽

2020 ◽

Vol 8 (1) ◽

Cited By ~ 1

Author(s):

Antonina Kouli ◽

Marta Camacho ◽

Kieren Allinson ◽

Caroline H. Williams-Gray

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

T Lymphocytes ◽

Substantia Nigra ◽

Amyloid Β ◽

Brain Regions ◽

Parkinson’S Disease Dementia ◽

Activated Microglia ◽

Cell Counts ◽

The Brain

AbstractParkinson’s disease dementia is neuropathologically characterized by aggregates of α-synuclein (Lewy bodies) in limbic and neocortical areas of the brain with additional involvement of Alzheimer’s disease-type pathology. Whilst immune activation is well-described in Parkinson’s disease (PD), how it links to protein aggregation and its role in PD dementia has not been explored. We hypothesized that neuroinflammatory processes are a critical contributor to the pathology of PDD. To address this hypothesis, we examined 7 brain regions at postmortem from 17 PD patients with no dementia (PDND), 11 patients with PD dementia (PDD), and 14 age and sex-matched neurologically healthy controls. Digital quantification after immunohistochemical staining showed a significant increase in the severity of α-synuclein pathology in the hippocampus, entorhinal and occipitotemporal cortex of PDD compared to PDND cases. In contrast, there was no difference in either tau or amyloid-β pathology between the groups in any of the examined regions. Importantly, we found an increase in activated microglia in the amygdala of demented PD brains compared to controls which correlated significantly with the extent of α-synuclein pathology in this region. Significant infiltration of CD4+ T lymphocytes into the brain parenchyma was commonly observed in PDND and PDD cases compared to controls, in both the substantia nigra and the amygdala. Amongst PDND/PDD cases, CD4+ T cell counts in the amygdala correlated with activated microglia, α-synuclein and tau pathology. Upregulation of the pro-inflammatory cytokine interleukin 1β was also evident in the substantia nigra as well as the frontal cortex in PDND/PDD versus controls with a concomitant upregulation in Toll-like receptor 4 (TLR4) in these regions, as well as the amygdala. The evidence presented in this study show an increased immune response in limbic and cortical brain regions, including increased microglial activation, infiltration of T lymphocytes, upregulation of pro-inflammatory cytokines and TLR gene expression, which has not been previously reported in the postmortem PDD brain.

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Growth Factor Therapy for Parkinson’s Disease: Alternative Delivery Systems

Journal of Parkinson s Disease ◽

10.3233/jpd-212662 ◽

2021 ◽

pp. 1-7

Author(s):

Sarah Jarrin ◽

Abrar Hakami ◽

Ben Newland ◽

Eilís Dowd

Keyword(s):

Parkinson’S Disease ◽

Gene Therapy ◽

Parkinson's Disease ◽

Growth Factors ◽

Growth Factor ◽

Ex Vivo ◽

Brain Regions ◽

Delivery Systems ◽

Alternative Delivery

Despite decades of research and billions in global investment, there remains no preventative or curative treatment for any neurodegenerative condition, including Parkinson’s disease (PD). Arguably, the most promising approach for neuroprotection and neurorestoration in PD is using growth factors which can promote the growth and survival of degenerating neurons. However, although neurotrophin therapy may seem like the ideal approach for neurodegenerative disease, the use of growth factors as drugs presents major challenges because of their protein structure which creates serious hurdles related to accessing the brain and specific targeting of affected brain regions. To address these challenges, several different delivery systems have been developed, and two major approaches—direct infusion of the growth factor protein into the target brain region and in vivo gene therapy—have progressed to clinical trials in patients with PD. In addition to these clinically evaluated approaches, a range of other delivery methods are in various degrees of development, each with their own unique potential. This review will give a short overview of some of these alternative delivery systems, with a focus on ex vivo gene therapy and biomaterial-aided protein and gene delivery, and will provide some perspectives on their potential for clinical development and translation.

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A Guide to the Generation of a 6-Hydroxydopamine Mouse Model of Parkinson’s Disease for the Study of Non-Motor Symptoms

Biomedicines ◽

10.3390/biomedicines9060598 ◽

2021 ◽

Vol 9 (6) ◽

pp. 598

Author(s):

Débora Masini ◽

Carina Plewnia ◽

Maëlle Bertho ◽

Nicolas Scalbert ◽

Vittorio Caggiano ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Mouse Model ◽

Survival Rates ◽

Dorsal Striatum ◽

Brain Regions ◽

Motor Symptoms ◽

Operative Care ◽

6 Hydroxydopamine ◽

Non Motor Symptoms

In Parkinson’s disease (PD), a large number of symptoms affecting the peripheral and central nervous system precede, develop in parallel to, the cardinal motor symptoms of the disease. The study of these conditions, which are often refractory to and may even be exacerbated by standard dopamine replacement therapies, relies on the availability of appropriate animal models. Previous work in rodents showed that injection of the neurotoxin 6-hydroxydopamine (6-OHDA) in discrete brain regions reproduces several non-motor comorbidities commonly associated with PD, including cognitive deficits, depression, anxiety, as well as disruption of olfactory discrimination and circadian rhythm. However, the use of 6-OHDA is frequently associated with significant post-surgical mortality. Here, we describe the generation of a mouse model of PD based on bilateral injection of 6-OHDA in the dorsal striatum. We show that the survival rates of males and females subjected to this lesion differ significantly, with a much higher mortality among males, and provide a protocol of enhanced pre- and post-operative care, which nearly eliminates animal loss. We also briefly discuss the utility of this model for the study of non-motor comorbidities of PD.

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Evaluation of Motor and Cognitive Performance in People with Parkinson’s Disease Using Instrumented Trail-Making Test

Gerontology ◽

10.1159/000515940 ◽

2021 ◽

pp. 1-7

Author(s):

Ram kinker Mishra ◽

Catherine Park ◽

He Zhou ◽

Bijan Najafi ◽

T. Adam Thrasher

Keyword(s):

Older Adults ◽

Parkinson’S Disease ◽

Parkinson's Disease ◽

Cognitive Performance ◽

Pairwise Comparison ◽

Walking Test ◽

Cognitively Normal ◽

Early Results ◽

Trail Making ◽

Changes Over Time

Introduction: Parkinson’s disease (PD) progressively impairs motor and cognitive performance. The current tools to detect decline in motor and cognitive functioning are often impractical for busy clinics and home settings. To address the gap, we designed an instrumented trail-making task (iTMT) based on a wearable sensor (worn on the shin) with interactive game-based software installed on a tablet. The iTMT test includes reaching to 5 indexed circles, a combination of numbers (1–3) and letters (A&B) randomly positioned inside target circles, in a sequential order, which virtually appears on a screen kept in front of the participants, by rotating one’s ankle joint while standing and holding a chair for safety. By measuring time to complete iTMT task (iTMT time), iTMT enables quantifying cognitive-motor performance. Purpose: This study’s objective is to examine the feasibility of iTMT to detect early cognitive-motor decline in PDs. Method: Three groups of volunteers, including 14 cognitively normal (CN) older adults, 14 PDs, and 11 mild cognitive impaireds (MCI), were recruited. Participants completed MoCA, 20 m walking test, and 3 trials of iTMT. Results: All participants enabled to complete iTMT with <3 min, indicating high feasibility. The average iTMT time for CN-Older, PD, and MCI participants were 20.9 ± 0.9 s, 32.3 ± 2.4 s, and 40.9 ± 4.5 s, respectively. After adjusting for age and education level, pairwise comparison suggested large effect sizes for iTMT between CN-older versus PD (Cohen’s d = 1.7, p = 0.024) and CN-older versus MCI (d = 1.57, p < 0.01). Significant correlations were observed when comparing iTMT time with the gait speed (r = −0.4, p = 0.011) and MoCA score (r = −0.56, p < 0.01). Conclusion: This study demonstrated the feasibility and early results supporting the potential application of iTMT to determine cognitive-motor and distinguishing individuals with MCI and PD from CN-older adults. Future studies are warranted to test the ability of iTMT to track its subtle changes over time.

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The Protective Role of Brain CYP2J in Parkinson’s Disease Models

Oxidative Medicine and Cellular Longevity ◽

10.1155/2018/2917981 ◽

2018 ◽

Vol 2018 ◽

pp. 1-12 ◽

Cited By ~ 6

Author(s):

Yueran Li ◽

Jinhua Wu ◽

Xuming Yu ◽

Shufang Na ◽

Ke Li ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Brain Regions ◽

Protective Role ◽

Neural Cells ◽

Endogenous Substrates ◽

6 Hydroxydopamine ◽

Myd88 Signaling ◽

Lps Treatment

CYP2J proteins are present in the neural cells of human and rodent brain regions. The aim of this study was to investigate the role of brain CYP2J in Parkinson’s disease. Rats received right unilateral injection with lipopolysaccharide (LPS) or 6-hydroxydopamine (6-OHDA) in the substantia nigra following transfection with or without the CYP2J3 expression vector. Compared with LPS-treated rats, CYP2J3 transfection significantly decreased apomorphine-induced rotation by 57.3% at day 12 and 47.0% at day 21 after LPS treatment; moreover, CYP2J3 transfection attenuated the accumulation of α-synuclein. Compared with the 6-OHDA group, the number of rotations by rats transfected with CYP2J3 decreased by 59.6% at day 12 and 43.5% at day 21 after 6-OHDA treatment. The loss of dopaminergic neurons and the inhibition of the antioxidative system induced by LPS or 6-OHDA were attenuated following CYP2J3 transfection. The TLR4-MyD88 signaling pathway was involved in the downregulation of brain CYP2J induced by LPS, and CYP2J transfection upregulated the expression of Nrf2 via the inhibition of miR-340 in U251 cells. The data suggest that increased levels of CYP2J in the brain can delay the pathological progression of PD initiated by inflammation or neurotoxins. The alteration of the metabolism of the endogenous substrates (e.g., AA) could affect the risk of neurodegenerative disease.

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Cognitive and Physiological Substrates of Impaired Sentence Processing in Parkinson's Disease

Journal of Cognitive Neuroscience ◽

10.1162/jocn.1993.5.4.480 ◽

1993 ◽

Vol 5 (4) ◽

pp. 480-498 ◽

Cited By ~ 38

Author(s):

Murray Grossman ◽

Susan Carvell ◽

Stephen Gollomp ◽

Matthew B. Stern ◽

Martin Reivich ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Frontal Cortex ◽

Sentence Processing ◽

Sentence Comprehension ◽

Short Term Memory ◽

Brain Regions ◽

Positron Emission ◽

Left Caudate ◽

Regional Cerebral Glucose Metabolism

Sentence comprehension is a complex process involving at least a grammatical processor and a procedural component that supports language computations. One type of cerebral architecture that may underlie sentence processing is a network of distributed brain regions. We report two experiments designed to evaluate the cognitive and physiological substrate of sentence processing diaculties in nondemented patients with Parkinson's disease (PD). In the first experiment, patients answered simple questions about sentences that varied in their computational demands. Group and individual patient analyses indicated that PD patients are significantly compromised on this task, and that their difficulties become more prominent as the computational demands of the sentences increase. We manipulated the set of sentences to stress performance aspects of sentence processing. PD patients were compromised in their ability to detect errors in the presence and nature of a sentence's grammatical morphemes, suggesting a deficit in selective attention, but their ability to answer questions about a sentence was not afFected by short-term memory factors. In the second experiment, positron emission tomography was used to correlate this pattern of sentence comprehension impairment with regional cerebral glucose metabolism (rCMRgl) obtained at rest in a representative subset of these PD patients. Grammatical comprehension and attention in sentence processing correlated significantly with mesial frontal rCMRgl. Regression analyses confirmed the central role of left mesial frontal cortex, and identified a subsidiary role for left caudate in overall sentence comprehension, for left dorsolateral frontal cortex in grammatical processing, and for bilateral dorsolateral frontal cortex in attending to the presence of grammatical features. We conclude that compromised mesial frontal functioning underlies in part the sentence processing deficit of these patients, and these data illustrate one method for mapping portions of a sentence processing mechanism onto a distributed cerebral architecture.

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A voxel-based PET study of dopamine transporters in Parkinson's disease: Relevance of age at onset

Neurobiology of Disease ◽

10.1016/j.nbd.2008.03.012 ◽

2008 ◽

Vol 31 (1) ◽

pp. 102-109 ◽

Cited By ~ 21

Author(s):

Andrea Panzacchi ◽

Rosa Maria Moresco ◽

Valentina Garibotto ◽

Angelo Antonini ◽

Clara Gobbo ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Age At Onset ◽

Dopamine Transporters ◽

Disease Relevance

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Cortical Thinning Associated with Age and CSF Biomarkers in Early Parkinson’s Disease Is Modified by the SNCA rs356181 Polymorphism

Neurodegenerative Diseases ◽

10.1159/000493103 ◽

2018 ◽

Vol 18 (5-6) ◽

pp. 233-238

Author(s):

Frederic Sampedro ◽

Juan Marín-Lahoz ◽

Saul Martínez-Horta ◽

Javier Pagonabarraga ◽

Jaime Kulisevsky

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Cognitive Decline ◽

De Novo ◽

Brain Regions ◽

Cortical Atrophy ◽

Csf Biomarkers ◽

Gene Encoding ◽

Cortical Thinning ◽

Age Related

The role of cerebrospinal fluid (CSF) biomarkers such as CSF α-synuclein and CSF tau in predicting cognitive decline in Parkinson’s disease (PD) continues to be inconsistent. Here, using a cohort of de novo PD patients with preserved cognition from the Parkinson’s Progression Markers Initiative (PPMI), we show that the SNCA rs356181 single nucleotide polymorphism (SNP) modulates the effect of these CSF biomarkers on cortical thinning. Depending on this SNP’s genotype, cortical atrophy was associated with either higher or lower CSF biomarker levels. Additionally, this SNP modified age-related atrophy. Importantly, the integrity of the brain regions where this phenomenon was observed correlated with cognitive measures. These results suggest that this genetic variation of the gene encoding the α-synuclein protein, known to be involved in the development of PD, also interferes in its subsequent neurodegeneration. Overall, our findings could shed light on the so far incongruent association of common CSF biomarkers with cognitive decline in PD.

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