Keynote 5: Can Indigenous Bacteria in the Gut Influence Brain Development and Behavior?

The mammalian gastrointestinal (GI) tract is colonized by trillions of microorganisms, collectively referred to as the gut microbiota. Recent animal studies from our laboratory and other groups have revealed that the gut microbiota has much wider effects on host physiology and development than originally believed, including the early-life programming of brain circuits involved in the control of emotions, motor activity, and social behavior.


Alterations in the composition and diversity of the gut microbiota have been identified in a number of neurodevelopmental and psychiatric disorders, including autism spectrum disorder (ASD). These findings have lent support to the theory that intestinal bacteria may play a role in the pathophysiology of human brain disorders. However, the cellular and molecular mechanisms mediating interactions between the gut microbiota and the developing brain remain poorly understood. This presentation will cover new findings from our laboratory demonstrating that microbial products derived from the indigenous (non-pathogenic) gut microbiota can be translocated into the developing brain and sensed by specific pattern-recognition receptors of the innate immune system. Finally, preliminary findings from our ongoing clinical studies will be presented.

Rochellys Diaz Heijtz, Associate Professor, Department of Neuroscience, Karolinska Institutet


Dr. Rochellys Diaz Heijtz is an Associate Professor of Translational Neuroscience at the Department of Neuroscience, Karolinska Institutet. Her research studies have a long-term goal of understanding the biological basis of neurodevelopmental disorders (ASD, ADHD), and how genes and the environment (prenatal and/or early postnatal) together influence typical and atypical brain development and behavior. Her research program includes basic studies investigating the impact of the gut microbiota (the microorganisms that inhabit our intestines) on the development of neuronal circuitries that control emotional, motor and social behavior. Furthermore, ongoing clinical studies are investigating the potential role of the gut microbiota in the pathophysiology of ASD and other neurodevelopmental disorders.