The Microbiome in Neurodegenerative Disease

Purpose of Review To review recent updates in our understanding of the microbiome and its relationship to neurodegenerative disease. Recent Findings Recognition of the microbiome's role in health and disease continues to expand. Recent techniques have focused on delineating the function and metabolism of resident organisms, which may correlate more directly with human physiology than identification of species. The role of the microbiome may be of particular importance in certain neurodegenerative diseases, including Parkinson's disease and Alzheimer's disease, among others. Summary The microbiome influences brain function and may play a role in neurodegenerative disease. Potential mechanisms include immunologic activation and promotion/attenuation of inflammation, as well as direct effects on induction and/or exacerbation of protein aggregation. The microbiome also has increasingly well-documented effects on the metabolism of therapeutic medications. Future studies will need to work through complex methodologic issues in order to identify which changes are truly disease-specific. Nevertheless, manipulation of the microbiome may soon improve our ability to treat neurodegenerative disease.