Session 9

The microbiome has emerged as a key regulator of disease. A shift in the microbial community, or dysbiosis, is correlated with the development of cancer, immune and cardiovascular diseases, decreased mental abilities and other behavioral affects. Evidence suggests a strong interaction between the gut microbiome, the gut and the well-being of the host.  Key functionality of such interactions involve modulating exposures and susceptibility to drugs and chemicals in foods and the environment.  These may be sequestered or altered by microbes, essentially acting as an additional organ system potentially equal in importance to the liver. Scientists are now starting to unravel microbiome–host interactions, including small molecules produced or altered by the microbiome that may drive this interaction. Growing knowledge suggests a need to identify molecules produced by the gut microbiota, the development of detection method and the re-evaluation of chemical safety to account for the impact of gut microbial influences that can vary greatly from individual to individual. These issues will be addressed in a two-part workshop, starting with this session, Microbiome I, which focused on systems-wide approaches in the determination of gut microbiome composition, organization, interactions, and the identification and detection of molecules produced.  In this, the Microbiome II workshop, a focus will be on understanding the toxicological impact of microbes, microbial communities and chemical transformations.  Findings involve the discovery and validation of biomarkers for gut microbiota composition and function.   The workshop combines presentations concerning how gut microbiota alter chemical toxicants, cutting-edge experimental model systems for evaluating microbiota influences in human and environmental toxicology, perspectives on relevance in drug development, and the challenges for risk assessment to account for microbial influences and their large variability.