Open AccessChanges in the levels and phosphorylation status of Akt, AMPK, CREB, and FoxO1 in hypothalamus of rainbow trout under conditions of enhanced glucosensing activity
Author(s) -
Cristina Otero-Rodiño,
Cristina Velasco,
Rosa AlvarezOtero,
Marcos A. LópezPatiño,
Jesús M. Míguez,
José L. Soengas
Publication year - 2017
Publication title -
journal of experimental biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.367
H-Index - 185
eISSN - 1477-9145
pISSN - 0022-0949
DOI - 10.1242/jeb.165159
Subject(s) - rainbow trout , ampk , hypothalamus , phosphorylation , creb , medicine , endocrinology , protein kinase b , foxo1 , chemistry , biology , protein kinase a , fishery , microbiology and biotechnology , fish <actinopterygii> , gene , transcription factor , biochemistry
There is no available information in fish about mechanisms linking glucosensing activation and changes in the expression of brain neuropeptides controlling food intake. Therefore, we assessed in rainbow trout hypothalamus the effects of raised levels of glucose on the levels and phosphorylation status of two transcription factors, FoxO1 and CREB, possibly involved in linking those processes. Moreover, we also aimed to assess the changes in the levels and phosphorylation status of two proteins possibly involved in the modulation of these transcription factors such as Akt and AMPK. Therefore, we evaluated in pools of hypothalamus incubated for 3h and 6h at 15 °C in modified Hanks’ medium containing 2, 4, or 8 mM D-glucose the response of parameters related to glucosensing mechanisms, neuropeptide expression, and levels and phosphorylation status of proteins of interest. The activation of hypothalamic glucosensing systems and the concomitant enhanced anorectic potential occurred in parallel with activation of Akt and inhibition of AMPK. The changes in these proteins would relate to neuropeptide expression through changes in the levels and phosphorylation status of transcription factors under their control, such as CREB and FoxO1, which displayed inhibitory (CREB) or activatory (FoxO1) responses to increased glucose.