Serum sirtuin 3 levels and multimodal abnormalities in brain structure and function in Parkinson's disease patients...

Depression is a common nonmotor symptom in patients with Parkinson's disease (PD). Currently, few studies have investigated the relationships between serum markers and neuroimaging changes associated with depression in PD patients.

To explore the correlations among depression, serum SIRT3 levels, and brain structural and functional alterations in PD patients.

The Hamilton Depression Scale-17 (HAMD-17) was used to assess depression. Serum SIRT3 levels were measured using an enzyme-linked immunosorbent assay (ELISA). Voxel-based morphometry (VBM) and resting-state functional magnetic resonance imaging (rs-fMRI) were used to examine structural and functional alterations.

Compared to healthy individuals, serum SIRT3 levels were lower in PD patients, especially in those with depression. PD patients with depression had lower total gray matter volume/total intracranial volume (GMV/TIV) ratio, and GMVs of the right amygdala, lower fractional amplitude of low-frequency fluctuations (fALFF) values of the left middle frontal gyrus (MidFG.L) and left superior parietal lobule (SPL.L), and altered functional connectivity(FC) primarily involving the Salience Network (SN) and the default Mode Network (DMN) compared to those without depression. Serum SIRT3 levels, total GMV/TIV ratios, and fALFF values of the MidFG.L and SPL.L have diagnostic value for PD patients with depression, and their combination can improve predictive accuracy.

Depression in PD patients is associated with lower serum SIRT3 levels, right amygdala atrophy, decreased spontaneous activity in MidFG.L and SPL.L, and altered FC in the DMN and SN.