Leptin, a hormone signaling molecule produced by fat cells, regulates feeding behavior and metabolism. In clinical trials, leptin supplementation has produced moderate weight loss in some obese patients, purportedly by inhibiting hunger and promoting feelings of being full. However, the brain circuits through which leptin alters feeding behavior in humans are not known. Kate Baicy et al. identify theleptin-regulated brain circuits involved in hunger. The authors performed functional magnetic resonance imaging (fMRI) in three individuals with a mutation in the gene encoding leptin (ob) to identify the brain circuits activated by viewing food. Leptin replacement reduced activation in brain areas linked to hunger (insula, parietal and temporal cortex) but increased activation in regions associated with inhibition and satiety (prefrontal cortex). Although such mutations are rare, and leptin supplementation is likely only beneficial in certain patients, the authors suggest that their findings could help identify new targets for treating obesity and other metabolic disorders.
Reference: https://tuncaydelibasi.weebly.com/blog/brain-circuits-link-leptin-and-hunger