Association between Brain Metabolite Changes and Glymphatic Dysfunction in Parkinson’s Disease: A Combined MRS and DTI-ALPS Study

Motivation: Parkinson's disease (PD) has been linked to impaired glymphatic function, affecting brain waste clearance. However, the interplay between glymphatic function and specific metabolite changes in PD is not well understood. Goal(s): This study aims to elucidate the relationship between glymphatic dysfunction and metabolic changes in PD and isolated REM sleep behavior disorder (iRBD), a potential precursor to PD. Approach: We assessed the glymphatic function using the ALPS-index from DTI-ALPS and quantified metabolite ratios in PD and iRBD patients with 3T MRS. Results: We found significant correlations between ALPS-index and key metabolites, suggesting an association between glymphatic dysfunction, neurotransmitter imbalances, and neuroinflammation in PD. Impact: Our findings reveal that glymphatic dysfunction in PD may underlie metabolic disruptions, potentially serving as markers for neurodegenerative process. These insights could open new avenues for metabolic and glymphatic-based diagnostic and therapeutic strategies in neurodegenerative diseases.