Oral microbiome as sensitive and specific biomarker of early stage Parkinson's disease through metatranscriptomic profiling.
On June 27 it has been published in Plos One that oral microbiome may represent a highly-accessible and informative microenvironment that could be used as a sensitive and specific biomarker for early stage Parkinson´s disease (PD). Using metatranscriptomic approaches the authors get to identify patients with Parkinson´s disease in a very early stage in a study of 48 PD subjects and 36 age- and gender-matched healthy controls.
... changes in specific microbial taxa were observed, including primarily bacteria, but also yeast and phage.
Testing of the diagnostic utility of the microbiome data revealed potentially robust performance with as few as 11 taxonomic features achieving a cross-validated area under the ROC curve of 0.90 and overall accuracy of 84.5%. Bioinformatic analysis of 167 different metabolic pathways supported shifts in a small set of distinct pathways involved in amino acid and energy metabolism among the organisms comprising the oral microbiome.
In parallel, the authors detected human gene expression changes in saliva of the Parkinson's disease patients analyzed:
This revealed significant changes in a set of 9 host mRNAs, several of which mapped to various brain functions and showed correlations with some of the significantly changed microbial taxa. Unexpectedly, we also observed robust correlations between many of the microbiota and functional measures, including those reflecting cognition, balance, and disease duration.
The results of this work appear to suggest that oral microbiome is not only a good biomarker for initial phases of Parkinson´s disease but also a element that could be involved in its pathophysiology.