Dietary vitamin B1, B2, and B6 intake influence the microbial composition and functional potential of the gut microbiome in Parkinson’s disease

Parkinson’s disease (PD) is the second-most common neurodegenerative disorder of the central nervous system, and its prevalence is on the rise. Gut microbiome dysbiosis has been linked to PD symptoms and pathogenesis, while certain nutrients (polyunsaturated fatty acids (PUFAs), saturated fatty acids (SFAs) and vitamins A, B1, B2, B3, B6, B12, C, D, and E) have shown protective effects against the disease. However, whether nutrient intake improves PD outcomes by alleviating gut microbiome dysbiosis remains unclear. In this study, we investigated whether dietary intake of the nutrients described above was associated with the microbial composition and functional potential of the PD gut microbiome. We analyzed the fecal microbiome of 285 participants with (n=184) or without (n=101) PD using 16S rRNA sequencing and compared microbiome composition to reported dietary nutrient intake. We found that high vitamin B2 intake is associated with increased Faith’s phylogenetic diversity of the PD gut microbiome. Vitamin B1 intake is associated with changes in both PD and non-PD microbiome composition, while vitamin B2 and B6 intake are uniquely associated with changes in PD microbiome composition. Further investigation found that low vitamin B1, B2, and B6 intake are associated with changes in the functional potential of the PD gut microbiome, with the potential to aggravate PD pathology. Our findings suggest that vitamin B1, B2, and B6 could play a role in remediating the PD gut microbiome, with the potential to also treat PD symptoms and progression via the gut-brain axis.