Quantitative susceptibility mapping of multiple system atrophy and Parkinson's disease correlates with neurotransmitter reference maps

• Published in: Neurobiology of disease Vol. 198; p. 106549
• Main Authors: Yan, Su, Lu, Jun, Duan, Bingfang, Zhu, Hongquan, Liu, Dong, Li, Li, Qin, Yuanyuan, Li, Yuanhao, Zhu, Wenzhen
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.08.2024; Elsevier
• Subjects: Multiple system atrophy; Neurotransmitter systems; Parkinson's disease; Quantitative susceptibility mapping; Spatial correlation analysis; Multiple system atrophy; Quantitative susceptibility mapping; Parkinson's disease; Spatial correlation analysis; Neurotransmitter systems
• ISSN: 0969-9961; 1095-953X
• DOI: 10.1016/j.nbd.2024.106549

Multiple system atrophy (MSA) and Parkinson's disease (PD) are neurodegenerative disorders characterized by α-synuclein pathology, disrupted iron homeostasis and impaired neurochemical transmission. Considering the critical role of iron in neurotransmitter synthesis and transport, our study aims to identify distinct patterns of whole-brain iron accumulation in MSA and PD, and to elucidate the corresponding neurochemical substrates. A total of 122 PD patients, 58 MSA patients and 78 age-, sex-matched health controls underwent multi-echo gradient echo sequences and neurological evaluations. We conducted voxel-wise and regional analyses using quantitative susceptibility mapping to explore MSA or PD-specific alterations in cortical and subcortical iron concentrations. Spatial correlation approaches were employed to examine the topographical alignment of cortical iron accumulation patterns with normative atlases of neurotransmitter receptor and transporter densities. Furthermore, we assessed the associations between the colocalization strength of neurochemical systems and disease severity. MSA patients exhibited increased susceptibility in the striatal, midbrain, cerebellar nuclei, as well as the frontal, temporal, occipital lobes, and anterior cingulate gyrus. In contrast, PD patients displayed elevated iron levels in the left inferior occipital gyrus, precentral gyrus, and substantia nigra. The excessive iron accumulation in MSA or PD correlated with the spatial distribution of cholinergic, noradrenaline, glutamate, serotonin, cannabinoids, and opioid neurotransmitters, and the degree of this alignment was related to motor deficits. Our findings provide evidence of the interaction between iron accumulation and non-dopamine neurotransmitters in the pathogenesis of MSA and PD, which inspires research on potential targets for pharmacotherapy. •Multiple system atrophy (MSA) and Parkinson's disease (PD) exhibited distinct whole-brain patterns of iron deposition.•The cortical topography of susceptibility alterations in MSA and PD correlated to reference maps of non-dopamine systems.•The susceptibility-neurotransmitter correlation provided indicators for monitoring disease severity in MSA and PD.