VMAT2 availability in Parkinson’s disease with probable REM sleep behaviour disorder

Bibliographic Details
Title: VMAT2 availability in Parkinson’s disease with probable REM sleep behaviour disorder
Authors: Mikaeel Valli, Sang Soo Cho, Carme Uribe, Mario Masellis, Robert Chen, Alexander Mihaescu, Antonio P. Strafella
Source: Molecular Brain, Vol 14, Iss 1, Pp 1-9 (2021)
Publisher Information: BMC, 2021.
Publication Year: 2021
Collection: LCC:Neurology. Diseases of the nervous system
Subject Terms: Parkinson’s disease, REM sleep behaviour disorder, Positron emission tomography, VMAT2, [11C]DTBZ, Neurology. Diseases of the nervous system, RC346-429
More Details: Abstract REM sleep behaviour disorder (RBD) can be an early non-motor symptom of Parkinson’s disease (PD) with pathology involving mainly the pontine nuclei. Beyond the brainstem, it is unclear if RBD patients comorbid with PD have more affected striatal dopamine denervation compared to PD patients unaffected by RBD (PD-RBD−). To elucidate this, we evaluated the availability of vesicular monoamine transporter 2 (VMAT2), an index of nigrostriatal dopamine innervation, in 15 PD patients with probable RBD (PD-RBD+), 15 PD-RBD−, and 15 age-matched healthy controls (HC) using [11C]DTBZ PET imaging. This technique measured VMAT2 availability within striatal regions of interest (ROI). A mixed effect model was used to compare the radioligand binding of VMAT2 between the three groups for each striatal ROI, while co-varying for sex, cognitive function and depression scores. Multiple regressions were also computed to predict clinical measures from group condition and VMAT2 binding within all ROIs explored. We observed a significant main effect of group condition on VMAT2 availability within the caudate, putamen, ventral striatum, globus pallidus, substantia nigra, and subthalamus. Specifically, our results revealed that PD-RBD+ had lower VMAT2 availability compared to HC in all these regions except for the subthalamus and substantia nigra, while PD-RBD− was significantly lower than HC in all these regions. PD-RBD− showed a negative relationship between motor severity and VMAT2 availability within the left caudate. Our findings reflect that both PD patient subgroups had similar denervation within the nigrostriatal pathway. There were no significant interactions detected between radioligand binding and clinical scores in PD-RBD+. Taken together, VMAT2 and striatal dopamine denervation in general may not be a significant contributor to the pathophysiology of RBD in PD patients. Future studies are encouraged to explore other underlying neural chemistry mechanisms contributing to RBD in PD patients.
Document Type: article
File Description: electronic resource
Language: English
ISSN: 1756-6606
Relation: https://doaj.org/toc/1756-6606
DOI: 10.1186/s13041-021-00875-7
Access URL: https://doaj.org/article/5dcd41733e1541eab8faeaa61f6f7af3
Accession Number: edsdoj.5dcd41733e1541eab8faeaa61f6f7af3
Database: Directory of Open Access Journals
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More Details
ISSN:17566606
DOI:10.1186/s13041-021-00875-7
Published in:Molecular Brain
Language:English