Objective: We aimed to investigate the role of synaptic vesicle glycoprotein 2A (SV2A) in Parkinson’s disease dementia (PDD) and Dementia with Lewy bodies (DLB) using [11C]UCB-J PET.

Background: Synaptic vesicle glycoprotein 2A (SV2A) is a transmembrane protein expressed ubiquitously in secretory vesicles, within the brain, which is critical for synaptic and mitochondrial function.

Method: [11C]UCB-J PET corrected with arterial input function, was used to assess SV2A levels in 9 PDD and 9 DLB patients compared to 12 healthy controls (HCs); HC [11C]UCB-J PET data was used from the MIND-MAPS Consortium. Regional volume of distribution (VT) was calculated using the one-tissue compartmental model with MIAKAT.

Results: PDD and DLB patients showed global loss of [11C]UCB-J VT compared to HCs, with greatest reductions in DLB. PDD patients had reduced [11C]UCB-J VT in the precentral gyrus, superior temporal gyrus, supramarginal gyrus, angular gyrus, superior parietal gyrus and the caudate, putamen, pallidum and substantia nigra (P<0.05) compared to HCs. DLB patients had reduced [11C]UCB-J VT in the frontal, temporal, parietal, insula and occipital cortex, as well as the caudate, thalamus and brainstem (P<0.05). In PDD and DLB patients loss of [11C]UCB-J VT correlated with global cognitive impairment (MMSE; P<0.05), reduced cognitive stability (PD-CRS sustained attention task; P<0.05), deficits in instrumental cortical functions (PD-CRS confrontation naming task; P<0.05) and with deficits in executive function (SCOPA-COG executive task; P<0.05).

Conclusion: Our findings demonstrate cortical and subcortical synaptic loss in patients with PDD and more prominently in patients with DLB that is associated with cognitive decline.

« Back to 2019 International Congress

MDS Abstracts - https://www.mdsabstracts.org/abstract/the-role-of-synaptic-vesicle-protein-2a-sv2a-in-patients-with-parkinsons-disease-dementia-and-dementia-with-lewy-bodies-an-in-vivo-11cucb-j-pet-study/