title: Imaging Striatal Microglial Activation in Patients with Parkinson's Disease.
abstract: This study investigated whether the second-generation translocator protein 18kDa (TSPO) radioligand, [18F]-FEPPA, could be used in neurodegenerative parkinsonian disorders as a biomarker for detecting neuroinflammation in the striatum. Neuroinflammation has been implicated as a potential mechanism for the progression of Parkinson's disease (PD). Positron Emission Tomography (PET) radioligand targeting for TSPO allows for the quantification of neuroinflammation in vivo. Based on genotype of the rs6791 polymorphism in the TSPO gene, 16 mixed-affinity binders (MABs) (8 PD and age-matched 8 healthy controls (HCs)), 16 high-affinity binders (HABs) (8 PD and age-matched 8 HCs) and 4 low-affinity binders (LABs) (3 PD and 1 HCs) were identified. Total distribution volume (VT) values in the striatum were derived from a two-tissue compartment model with arterial plasma as an input function. There was a significant main effect of genotype on [18F]-FEPPA VT values in the caudate nucleus (p = 0.001) and putamen (p < 0.001), but no main effect of disease or disease x genotype interaction in either ROI. In the HAB group, the percentage difference between PD and HC was 16% in both caudate nucleus and putamen; in the MAB group, it was -8% and 3%, respectively. While this PET study showed no evidence of increased striatal TSPO expression in PD patients, the current findings provide some insights on the possible interactions between rs6791 polymorphism and neuroinflammation in PD.
authors.affiliation: Division of Brain, Imaging and Behaviour-Systems Neuroscience, Toronto Western Research Institute, University Hospital Network, University of Toronto, Toronto, Ontario, Canada; Research Imaging Centre, Centre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Koshimori
authors.affiliation: Department of Human Anatomy and Cell Science, Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada.
authors.forename: Ji-Hyun
authors.initials: JH
authors.lastname: Ko
authors.affiliation: Research Imaging Centre, Centre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Romina
authors.initials: R
authors.lastname: Mizrahi
authors.affiliation: Research Imaging Centre, Centre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Pablo
authors.initials: P
authors.lastname: Rusjan
authors.affiliation: Research Imaging Centre, Centre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Rostom
authors.initials: R
authors.lastname: Mabrouk
authors.affiliation: Research Imaging Centre, Centre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Mark F
authors.initials: MF
authors.lastname: Jacobs
authors.affiliation: Division of Brain, Imaging and Behaviour-Systems Neuroscience, Toronto Western Research Institute, University Hospital Network, University of Toronto, Toronto, Ontario, Canada; Research Imaging Centre, Centre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Leigh
authors.initials: L
authors.lastname: Christopher
authors.affiliation: Division of Neurosurgery, Toronto Western Hospital, University Hospital Network, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Clement
authors.initials: C
authors.lastname: Hamani
authors.affiliation: Morton and Gloria Shulman Movement Disorder Unit & Edmond.J. Safra Program in Parkinson Disease, Toronto Western Hospital, University Hospital Network, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Anthony E
authors.initials: AE
authors.lastname: Lang
authors.affiliation: Research Imaging Centre, Centre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Alan A
authors.initials: AA
authors.lastname: Wilson
authors.affiliation: Research Imaging Centre, Centre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Sylvain
authors.initials: S
authors.lastname: Houle
authors.affiliation: Division of Brain, Imaging and Behaviour-Systems Neuroscience, Toronto Western Research Institute, University Hospital Network, University of Toronto, Toronto, Ontario, Canada; Research Imaging Centre, Centre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, Canada; Morton and Gloria Shulman Movement Disorder Unit & Edmond.J. Safra Program in Parkinson Disease, Toronto Western Hospital, University Hospital Network, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Antonio P
authors.initials: AP
authors.lastname: Strafella
mesh_terms: D000368:Aged; D003342:Corpus Striatum / Q000000981:diagnostic imaging* / Q000378:metabolism; D005260:Female; D005838:Genotype; D006801:Humans; D007249:Inflammation / Q000000981:diagnostic imaging* / Q000235:genetics; D008297:Male; D017628:Microglia / Q000000981:diagnostic imaging* / Q000378:metabolism; D008875:Middle Aged; D059906:Neuroimaging; D010300:Parkinson Disease / Q000000981:diagnostic imaging* / Q000235:genetics / Q000378:metabolism; D011110:Polymorphism, Genetic; D011877:Radionuclide Imaging