Venue: Centre Broca
Invited by Alice Fermigier (Ferreira and Trifilieff’s team – NutriNeuro)
A memo from your gut: cholinergic modulation of the gut-hippocampus axis
Various endocrine, neuropeptide, and neural signals regulate appetite, meal size, and satiety. Emerging evidence reveals that in addition to influencing food intake control, these energy status-related biological systems also play a critical role in learning and memory function, particularly with regards to remembering meal-associated episodic experiences and visuospatial information relevant for foraging behavior. Emerging findings identify the hippocampus as a critical brain region interfacing eating-relevant biological signals with learning and memory. Hippocampal neurons express receptors for multiple neuropeptides and circulating hormones associated with energy balance control, and modulation of these receptors potently influences both appetitive (e.g., responsivity to environmental food cues) and consummatory (e.g., meal size control) behaviors. In addition to peptide systems, we’ve recently identified a neural pathway through which within-meal physiological satiation signals engage hippocampal neurons to influence learning and memory. The vagus nerve, which is a principal conduit of gut-brain satiation signaling, communicates to hippocampal neurons through a multisynaptic pathway that includes the medial septum as a critical relay. This communication is functionally relevant to hippocampal-dependent memory function and is modulated by the gut-derived hormone, ghrelin, through its action on vagal afferent neurons. Our ongoing research is exploring the neural mechanisms orchestrating this newly identified gut-to-hippocampus axis, with a recent focus on septal acetylcholine signaling as a critical interface between vagal and dietary influences on hippocampal function. Collective results are identifying neurobiological mechanisms mediating the bidirectional relationship between memory and eating behavior.
Dr. Kanoski’s research focuses on the neurobiological control of food intake and body weight regulation. More specifically his laboratory focuses on understanding how the brain processes peripherally- and centrally-derived hormonal signals to control learned and motivated aspects of feeding behavior, as well as to examine how these neuroendocrine signaling systems contribute to and are compromised by obesity and related metabolic disorders. At the center of this research is the hippocampus; a brain region traditionally linked with memory function, but more recently shown to control higher-order aspects of feeding behavior. The lab also focuses on exploring the relationship between consuming saturated fatty acids and refined carbohydrates (i.e., “Western diets”) and the development of hippocampal dysfunction, cognitive impairment, and Alzheimer’s pathology.
PhD seminars are organized by the NBA, Bordeaux Neurocampus, and the Bordeaux Neurocampus Graduate Program