| First Author | Iskandar K | Year | 2010 |
| Journal | Am J Physiol Endocrinol Metab | Volume | 298 |
| Issue | 4 | Pages | E787-98 |
| PubMed ID | 20103739 | Mgi Jnum | J:162892 |
| Mgi Id | MGI:4820483 | Doi | 10.1152/ajpendo.00512.2009 |
| Citation | Iskandar K, et al. (2010) PDK-1/FoxO1 pathway in POMC neurons regulates Pomc expression and food intake. Am J Physiol Endocrinol Metab 298(4):E787-98 |
| abstractText | Both insulin and leptin signaling converge on phosphatidylinositol 3-OH kinase [PI(3)K]/3-phosphoinositide-dependent protein kinase-1 (PDK-1)/protein kinase B (PKB, also known as Akt) in proopiomelanocortin (POMC) neurons. Forkhead box-containing protein-O1 (FoxO1) is inactivated in a PI(3)K-dependent manner. However, the interrelationship between PI(3)K/PDK-1/Akt and FoxO1, and the chronic effects of the overexpression of FoxO1 in POMC neurons on energy homeostasis has not been elucidated. To determine the extent to which PDK-1 and FoxO1 signaling in POMC neurons was responsible for energy homeostasis, we generated POMC neuron-specific Pdk1 knockout mice (POMCPdk1(-/-)) and mice selectively expressing a constitutively nuclear (CN)FoxO1 or transactivation-defective (Delta256)FoxO1 in POMC neurons (CNFoxO1(POMC) or Delta256FoxO1(POMC)). POMCPdk1(-/-) mice showed increased food intake and body weight accompanied by decreased expression of Pomc gene. The CNFoxO1(POMC) mice exhibited mild obesity and hyperphagia compared with POMCPdk1(-/-) mice. Although expression of the CNFoxO1 made POMCPdk1(-/-) mice more obese due to excessive suppression of Pomc gene, overexpression of Delta256FoxO1 in POMC neurons had no effects on metabolic phenotypes and Pomc expression levels of POMCPdk1(-/-) mice. These data suggest a requirement for PDK-1 and FoxO1 in transcriptional regulation of Pomc and food intake. |
