The gut microbiome in Parkinson's disease

Abstract

The vast majority of Parkinson's disease (PD) cases are of sporadic origin and despite extensive research in recent years, the etiology still remains unclear. Several current case control studies are aiming to characterize aputative PD-specific composition of the gut microbiome, reflecting the potential relevance of microbiota in the pathogenesis of PD. Although methodologies and cohort sizes differed, the currently available studies showed reproducible or consistent results in terms of PD-specific alterations to the intestinal bacteria. By applying metagenomic sequencing procedures, it is even possible to distinguish PD cases from healthy individuals at avery early disease stage by means of individually modified microbiota. Among others, microbiota that are associated with an altered intestinal barrier or immune function, such as Akkermansia, Lactobacillus, Faecalibacterium and Prevotella were significantly over-represented or under-represented. There may even be aprodromal microbiome, as acomparable microbial shift is also found in patients with rapid eye movement (REM) sleep behavior disorder (RBD), arisk factor for the later development of synucleinopathies, such as PD.