Figure 2.

Examples of gut-brain circuits uncovered using technological advances. Chemogenetic, optogenetic, and loss-of-function studies have elucidated individual cell types that can regulate feeding in the gut, vagus, and NST/AP [65,99,104,179,180]. One circuit that consists of cells in all three of these nodes integrates intestinal distension and CCK detection to suppress food intake [65,99]. Another circuit that originates in the gut has also been shown to be sufficient and necessary to signal post-ingestive sugar preference [108].