Associations between the Relative Abundance of Butyrate-Producing and Mucin-Degrading Taxa and Parkinson's Disease

Abstract

BackgroundParkinson’s disease (PD) is a neurodegenerative disorder characterised by motor and non-motor symptoms. Differences in the gut microbiome composition and diversity have been implicated in PD aetiology. This study aimed to further explore the interplay between the gut microbiome and PD in the South African context.MethodsGut microbial data (cases: n = 16; controls: n = 42) was generated using a 16S rRNA gene (V4) primer pair. The DADA2 pipeline was used for data preparation and taxa classification. Alpha-diversity was assessed using the Shannon and Simpson diversity metrics, whereas beta-diversity was assessed with the permutational multivariate analysis of variance (PERMANOVA) adonis in QIIME2. Differentially abundant taxa between cases and controls were evaluated using Analysis of Compositions of Microbiomes with Bias Correction (ANCOM-BC).ResultsAlpha-diversity was not associated with PD status, however, beta-diversity was associated with PD (q = 0.008). Furthermore, PD was associated with the depleted relative abundance of Faecalibacterium (q = 0.007), Roseburia (q = 0.030), Dorea (q = 0.015), and Veillonella (q < 0.001), and the enriched relative abundance of Akkermansia (q = 0.015) andVictivallis (q < 0.001).ConclusionOur study found gut microbiome alterations with a reduction in butyrate-producing bacteria (e.g. Faecalibacterium andRoseburia) and an increase in mucin-degrading bacteria (Akkermansia) in PD cases compared to controls. These alterations might be associated with heightened gut permeability and inflammation. Longitudinal studies can address the question of whether these microbiome differences are a risk factor for or are consequent to the development of PD.

Note:
Funding declaration: Research reported in this study was supported by the South African Medical Research Council for the “Shared Roots” Flagship Project, Grant no. MRC-RFA-IFSP-01-2013/SHARED ROOTS” through funding received from the South African National Treasury under its Economic Competitiveness and Support Package.

Conflict of Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Ethical Approval: This study is a sub-study of the project entitled “Understanding the SHARED ROOTS of Neuropsychiatric Disorders and modifiable risk factors of cardiovascular disease” (ethics number: S22/05/094 (PhD) substudy N13/08/115) which was approved by the Stellenbosch University Health Research Ethics Committee 1 (HREC1).

Keywords: butyrate-producing bacteria, Parkinson's Disease, beta-diversity, Gut microbiome, gut-brain-axis, alpha-diversity