UCLA

The gut microbiome recently has been associated with many diseases, with studies showing that the microbiome can affect aspects of neurological function, brain activity, and behavior. While several digestive symptoms are well-known non-motor features of Parkinson’s disease (PD), the role of the gut microbiome in the neurodegenerative process of PD remains underexplored. Here we recruited a cohort of 81 PD patients and 56 healthy controls from central California. We collected ethanol fixed fecal samples and conducted microbial composition analyses. Beta diversity analysis demonstrated compositional differences in the microbiome of PD patients and controls. We also identified specific bacterial genera that were associated with PD status using negative binomial models to determine the differential abundance of taxa (DESeq2 package in R; B-H adjusted p-value < 0.05). We also identified specific bacterial genera significantly different in abundance between higher levodopa equivalent dose (LED) use PD patients and lower LED use PD patients. Furthermore, several specific bacterial families were found to be highly correlated with a constipation score in PD patients and controls. In conclusion, we found differences in the gut microbiome composition comparing PD cases and controls and identified specific bacterial genera that seemed to be associated with PD status. In the future, investigations are needed to identify underlying pathophysiologic pathways influenced by the gut microbiome in PD.