3 C-MR as a Diagnostic and Non-invasive Tool for Quantification of Brain Glycogen in Adult Polyglucosan Body Disease (APBD): A Pilot Case Study in Mouse

In this we developed 13C-glycogen MRI scan method for the glycogen storage disease (GSD) to quantify pathogenic glycogen levels in the brain. According to our MR study in glycogen branching enzyme (GBE) knockin mice, that model the prototypical Adult polyglucosan body disease (APBD) a type of GSD, brain 13C-glycogen is detectable if animals are fed with a 13C6-glucose tracer as the only carbohydrate source. 13C-glycogen is detectable only at the symptomatic age. The muscle 13C-glycogen was detectable at both asymptomatic and symptomatic ages but was higher in symptomatic age. These MR results were confirmed by NMR and biochemical analysis of glycogen in brain and muscle tissues. This technique to detect the brain glycogen in neurological GSD may act as non-invasive biomarker and enable to assess the efficacy of therapeutic targets