LAUSR

BACKGROUND Intestinal inflammation and gut microbiota dysbiosis contribute to Parkinson's Disease (PD) pathogenesis and growing evidence suggests associations between inflammatory bowel diseases (IBD) and PD. Considered as markers of chronic gastrointestinal inflammation, elevated serum anti-Saccharomyces cerevisiae antibody (ASCA) levels, against certain gut fungal component, are related to IBD, but their effect on PD is yet to be investigated. METHODS Serum ASCA IgG and IgA levels were measured using an enzyme-linked immunosorbent assay, and the gut mycobiota communities were investigated using ITS2 sequencing and analyzed using the Qiime pipeline. RESULTS The study included 393 subjects (148 healthy controls [HC], 140 with PD, and 105 with essential tremor [ET]). Both serum ASCA IgG and IgA levels were significantly higher in PD group than in those in ET or HC groups. Combining serum ASCA levels and the occurrence of constipation could discriminate patients with PD from controls (the areas under the curve [AUC]=0.81, 95% confidence interval [CI]: 0.76-0.86) and from patients with ET (AUC=0.85, 95%CI: 0.79-0.89). Furthermore, the composition of the gut fungal community differed between the PD and HC groups. The relative abundances of Saccharomyces cerevisiae, Aspergillus, Candida solani, Aspergillus flavus, ASV601_Fungi, ASV866_Fungi, ASV755_Fungi were significantly higher in the PD group and enriched Malassezia restricta was found in the HC group. CONCLUSIONS Our study identified elevated Serum ASCA levels and enriched gut Saccharomyces cerevisiae in de novo PD.