Hormonal Regulation of Obesity—Leptin, the so-called satiety hormone, is made by fat cells and helps regulate energy balance by inhibiting hunger. One brain area particularly responsive to leptin is the arcuate nucleus of the hypothalamus (ARC). The ARC contains proopiomelanocortin (POMC) neurons that are crucial for regulating both energy and glucose balance. Leptin is known to trigger POMC neuron activity by reducing the amount of gamma-aminobutyric acid (GABA) released onto POMC neurons. (GABA is the primary inhibitory neurotransmitter in the mammalian central nervous system). In a paper published earlier this year in Nature Communications, Dr. Young-Hwan Jo and colleagues showed that leptin’s action on GABA release is influenced by glucose levels, indicating that the interplay between glucose and leptin signaling at GABAergic synapses to POMC neurons is critical for determining the strength of the inhibitory tone towards POMC neurons. Dr. Jo is assistant professor of medicine and of molecular pharmacology.
Posted on: Tuesday, September 01, 2015