Dissecting Molecular and Cellular Mechanisms for Communication Across the Microbiota-Gut-Brain Axis

Women's Council Recipient
Elaine Hsiao, Ph.D.
University of California, Los Angeles

As the body’s control center, the brain integrates complex sensory information and rapidly responds to the needs and experiences of every body system. In line with the finding that our bodies are comprised of up to 10X more bacterial cells than human cells, which contribute 360X more genes than does the human genome, it is now known that the brain communicates bidirectionally with the resident microbes that make up “us”. Increasing evidence indicates that the gut microbiome fundamentally impacts the development and function of the nervous system, modifying complex behaviors, neurotransmitter signaling, transport of chemicals between the blood and brain, activation of brain immune cells and global brain gene expression. Such long-range interactions between the brain and microbiome support the ability of microbe-based therapies to treat various symptoms of neurological diseases in mice and humans. Overall, that indigenous microbes have the remarkable capacity to modulate neural activity and behavior suggests that elucidating the interactions between microbes and the nervous system will provide new insights into brain development and function, and potentially uncover tractable strategies for treating complex nervous system disorders. Currently, mechanisms underlying how the gut microbiota signals to the brain are lacking and little is known about the precise functions of particular bacterial species. To uncover key mechanisms that enable interactions between the microbiota and brain, we will examine how peripheral neuronal activity is affected by the gut microbiota with aims to identify specific microbes and microbial signals that modulate neuronal activity.