Research Title: Microbiome influences on neural activity: Investigating the electrophysiological impact of the microbiome
Project Background: Microorganisms within our gut are able to influence our behaviors. A strong link between a changed microbiome and increases in anxious behaviors has been found in both humans and animal models. Anxiety and mood disorders constitute a significant global burden with lifetime prevalence of around 1/5, and cost EU states up to 4% of GDP. Microbiome changes have also been linked with changes in brain anatomy, and molecular and genetic markers of neural activity in areas linked with mood and cognition. This implies that neuronal activity underpinning behaviors is influenced by the microbiome. However, studies to-date have lacked the temporal resolution to reveal neuronal activity during behavior, and how this is affected by microbiome perturbations. This project will be the first to directly address the question of how behaviorally relevant neuronal network activity is impacted by microbiome perturbations.
A rodent model of early life adversity (the maternal separation model) will be studied as it has been shown to exhibit alterations in the microbiome along with increased anxiety-like behaviors, compared to controls. Additionally, a probiotic diet has been shown to ameliorate the behavioral symptoms, suggesting a causal role for the microbiome in determining these behaviors.
The project will use state-of-the-art electrophysiological recordings of neuronal activity within two brain regions involved in anxiety (prelimbic cortex and amygdala). Recordings of neural activity at single cell resolution will be made in both anaesthetized and awake behaving animals across control, maternal stress, and maternal stress with probiotic diet groups. Analysis of the activity within, and functional connectivity between the two regions will provide a unique view into how changes in the microbiome alters brain activity driving anxiety-like behaviors, and may identify potential targets for therapeutic intervention in anxiety and mood disorders at the microbiome and neuronal network levels.