[ 18 F]FDG PET/CT Studies in Transgenic Hualpha-Syn (A53T) Parkinson's Disease Mouse Model of α-Synucleinopathy

Front Neurosci. 2021 Jun 15:15:676257. doi: 10.3389/fnins.2021.676257. eCollection 2021.

Abstract

Transgenic mice line M83 that express the A53T mutant α-synuclein protein at six times the level of endogenous mice α-synuclein are a model of α-synucleinopathy found in Parkinson's disease (PD). This Hualpha-Syn (A53T) PD model is useful in assessing non-motor deficits at earlier stages of onset of PD. We report findings on metabolic changes using [18F]FDG PET/CT in the Hualpha-Syn (A53T) PD mouse model in comparison to non-carrier mice. Whole-body PET/CT imaging of male and female mice were carried out 2 h after [18F]FDG ip administration under 3% isoflurane anesthesia. Brain images were analyzed with PET images coregistered to a mouse brain MRI template. Hualpha-Syn (A53T) mice had significantly lower [18F]FDG uptake in several brain regions compared to the no-carrier mice. Significant hind limb muscle and lower spinal cord [18F]FDG hypometabolism at 9 months of age in A53T PD mice was also indicative of neurodegenerative disease, with a progressive motoric dysfunction leading to death. Significant decrease (up to 30%) in [18F]FDG uptake were observed in 9-month old male and female Hualpha-Syn (A53) mice. This is consistent with the cortical hypometabolism in PD patients. Hualpha-Syn (A53) mice may thus be a suitable model for studies related to PD α-synucleinopathy for the discovery of new biomarkers.

Keywords: Hualpha-Syn A53T mice; Parkinson’s disease; [18F]FDG PET/CT; brain; hypometabolism; limb muscle; spinal cord; α-synuclein.