A/Prof Andrew Holmes (Charles Perkins Centre, School of Life and Environmental Sciences, USYD)

Title: Behavioural microbiomics: How the environment can influence behaviour via the gut

Abstract: The past two decades have resulted in a wealth of evidence that our gut microbiome profoundly influences many aspects of our physiology. It is now clear that this extends to behaviour and is relevent to many mental health issues including autism, depression and eating disorders. The concept of the microbiome-gut-brain axis has emerged as a framework to better understand these diseases. I will give a background to the history of this new field and then discuss our recent research on how to promote health via mechanisms dependent on microbial metabolism, particularly using dietary glycans (fibre). A major challenge is that both host and microbial responses to dietary glycan supplementation are variable, poorly predictable and the underlying mechanisms to deliver effects not well understood. We postulate that a significant component of this variability arises from interactive effects of other diet components (especially protein) with microbial community assembly processes. Our aim is to identify the ecological mechanisms that constrain the host and microbiome response to dietary fibre components and elucidate design principles to improve diet-based interventions in a range of diseases including metabolic disease, immunotherapy for cancer and mental health.