Differences in intestinal microbiota in Parkinson's disease and isolated REM sleep behavior disorder

Area of Science:

• Microbiology
• Neuroscience
• Gastroenterology

Background:

• Parkinson's disease (PD) is linked to altered gut microbiota composition.
• Investigating the prodromal phase of PD, such as isolated REM sleep behavior disorder (iRBD), is crucial for understanding causality.

Purpose of the Study:

• To compare the gut microbiome composition in individuals with iRBD, clinical PD, and healthy controls (HC).
• To identify specific microbial changes associated with early and clinical stages of PD.

Main Methods:

• Stool samples were collected from three groups: iRBD (n=32), PD (n=23), and HC (n=34).
• Microbiome analysis focused on beta-diversity and the abundance of specific bacterial species.

Main Results:

• Significant differences in beta-diversity were observed between PD patients and HC (p=0.025), and between iRBD patients and HC (p=0.003).
• An increase in proinflammatory bacteria was noted in both iRBD and PD groups.
• A decrease in short-chain fatty acid (SCFA)-producing bacteria was found in PD patients.

Conclusions:

• Gut microbiome alterations are present in the prodromal stages (iRBD) and clinical stages of Parkinson's disease.
• Changes in microbial composition, including increased proinflammatory species and decreased SCFA producers, may play a role in PD pathogenesis.