Distinct Bile Acid Signature in Parkinson's Disease With Mild Cognitive Impairment

BACKGROUNDS: Bile acid (BA) plays a crucial role in various neurodegenerative diseases, including Parkinson's disease (PD). However, no clinical evidence supports BA's potential role in patients with PD with mild cognitive impairment (PD-MCI). OBJECTIVES: This study aimed at investigating the differential BA profile between patients with PD-MCI and those with normal cognitive function (PD-NC). METHODS: Ultra-high performance liquid chromatography-MS/MS was applied for BA quantitation. After between-group differences of the BA profile were addressed, orthogonal projections to latent structures—discriminant analysis (OPLS-DA) and the area under the receiver-operating-characteristic curve (AUC-ROC) were implemented for further verification. RESULTS: Lower levels of chenodeoxycholic acid (CDCA), cholic acid (CA), and ursodeoxycholic acid (UDCA) were significantly associated with PD-MCI (p < 0.01 for both; VIP ≈ 2.67, 1.66, and 1.26, respectively). AUC-ROC were 78.1, 74.2, and 74.5% for CDCA, CA, and UDCA, respectively. CONCLUSION: CA, CDCA, and UDCA might be distinct BA signatures for patients with PD-MCI.