Figure 2.

Model of CNS leptin regulation of glucose metabolism. Leptin is secreted by adipocytes, enters the CNS, and acts on its receptor expressed in key brain areas that regulate metabolism. Leptin inhibits neuropeptide and agouti-related peptide (NPY/AgRP) neurons and stimulates pro-opiomelanocortin (POMC) neurons in the ARC, responses that promote glucose uptake in peripheral tissues and the suppression of glucose production from the liver. In addition, leptin action in the VMH stimulates glucose uptake in peripheral tissues and this brain area is also implicated in the regulation of glucagon secretion. ARC, arcuate nucleus; VMH, ventromedial hypothalamus; PVN, paraventricular nucleus; Mc4r; melanocortin-4 receptor; LepRb, leptin receptor; BAT, brown adipose tissue.[104]