Title: The role of the microbiome in health and disease
Speaker: Prof Emad M El-Omar, St George & Sutherland Clinical School, UNSW
Over the past decade, it has become abundantly clear that the gut microbiota play a crucial role in human health and disease. Diversity of the microbiota is a surrogate for health and loss of diversity is characteristic of many human diseases, including multi-organ dysfunction in the critical care setting. This “dysbiosis” represents an abnormal state that predisposes to a variety of diseases by maximising the harmful effect of pathobionts and the loss of beneficial effects of symbionts.The consequences of this dysbiosis include disruption of mucosal barrier function (hyperpermeability), translocation of micro-organisms and their products and initiation of a state of low-grade chronic inflammation, the root of all evil in human illness. The dysbiosis may also produce direct genotoxic damage to the stem cell compartment within the bowel. Recent work has identified broad changes in the composition of the gut microbiota that predispose to CRC and IBD and also specific examples of bacterial groups that have a clear harmful effect. Advances in sequencing technology have allowed a rapid and affordable description of the gut microbiota in health and disease but the greater challenge remains in being able to interpret the functional consequences of the dysbiotic changes and the mechanisms involved. On the positive side, the beneficial microbiota could potentially be a source of restitution and recovery and our efforts are now focussed on understanding how to utilise such microbiota in therapeutic strategies designed to prevent, alleviate and treat many human diseases.