Using 1H-Magnetic Resonance Spectroscopy to Evaluate the Efficacy of Pharmacological Treatments in Parkinson's Disease: A Systematic Review.

Parkinson's Disease (PD) is the fastest-growing neurological disorder, characterized by the degeneration of dopaminergic neurons. Treatments remain symptomatic, and objective biomarkers for therapeutic response are lacking. This review aims to evaluate the potential of Proton Magnetic Resonance Spectroscopy (1H-MRS) to provide objective and reproducible biomarkers for monitoring treatment response in PD. This systematic review followed PRISMA guidelines. Articles were searched in PubMed, Web of Science, Scopus, and Embase, and studies employing 1H-MRS to evaluate pharmacological treatments in PD were included, analyzing pre- and post-treatment changes. Six studies were included, investigating cannabinoids, dopamine agonists, monoamine oxidase B inhibitors, and levodopa. Key metabolites analyzed were N-acetylaspartate, Creatine, Choline, myo-Inositol, and Glx (glutamate+glutamine). Increases in NAA, a marker of neuronal integrity and mitochondrial function, suggested neuroprotective mechanisms of dopaminergic drugs, while stable Cho and mI levels, markers of membrane metabolism and inflammatory processes, suggested limited short-term responsiveness. This is the first systematic review evaluating 1H-MRS for monitoring neurometabolic changes induced by pharmacological treatments in PD. Observed metabolite changes appear to reflect treatment mechanisms and potential neuroprotective properties. Findings suggest that 1H-MRS may serve as an objective biomarker for assessing therapeutic efficacy and potential neuroprotective drug effects, although further studies are needed to confirm its clinical utility.