Neuroenergetic alterations in neurodegenerative diseases: A systematic review and meta-analysis of in vivo31P-MRS studies.

ABSTRACT

Phosphorus magnetic resonance spectroscopy (31P-MRS) is applied for non-invasive studies of neuroenergetic metabolism in neurodegenerative diseases. However, the findings are inconsistent and have not yet been tested in meta-analyses. To address this gap, we performed a systematic review of 29 studies and conducted meta-analyses for 9 studies on Alzheimer's disease (AD, n=140 patients), 9 studies on Parkinson's disease (PD, n=183 patients), 3 studies on Progressive Supranuclear Palsy (PSP, n=42 patients), and 2 studies on Multiple System Atrophy (MSA, n=24 patients). Compared to controls, AD patients had a higher ratio of phosphomonoesters/phosphodiesters (PME/PDE) in the frontal lobe (MD=0.049, p=0.0003); PD patients showed decreases in PME/PDE in the putamen (MD=-0.050, p=0.023) and adenosine triphosphate/inorganic phosphate (ATP/Pi) in the midbrain (MD=-0.274, p=0.002); PSP patients presented increased phosphocreatine (PCr)/Pi in the basal ganglia (MD=0.556, p=0.030) and adenosine diphosphate (ADP)/Pi in the occipital lobe (MD=0.005, p=0.009); no significant effects were observed in MSA. Here, our review underlines the importance of 31P-MRS in the characterization of distinct neuroenergetic changes and its potential to improve the diagnosis and follow-up of neurodegenerative diseases.