Activation of insulin and IGF-1 signaling pathways by melatonin through MT1 receptor in isolated rat pancreatic islets.
J Pineal Res
; 44(1): 88-94, 2008 Jan.
Article
em En
| MEDLINE
| ID: mdl-18078453
ABSTRACT
Melatonin diminishes insulin release through the activation of MT1 receptors and a reduction in cAMP production in isolated pancreatic islets of neonate and adult rats and in INS-1 cells (an insulin-secreting cell line). The pancreas of pinealectomized rats exhibits degenerative pathological changes with low islet density, indicating that melatonin plays a role to ensure the functioning of pancreatic beta cells. By using immunoprecipitation and immunoblotting analysis we demonstrated, in isolated rat pancreatic islets, that melatonin induces insulin growth factor receptor (IGF-R) and insulin receptor (IR) tyrosine phosphorylation and mediates the activities of the PI3K/AKT and MEK/ERKs pathways, which are involved in cell survival and growth, respectively. Thus, the effects of melatonin on pancreatic islets do not involve a reduction in cAMP levels only. This indoleamine may regulate growth and differentiation of pancreatic islets by activating IGF-I and insulin receptor signaling pathways.
Buscar no Google
Base de dados:
MEDLINE
Assunto principal:
Fator de Crescimento Insulin-Like I
/
Receptor de Insulina
/
Ilhotas Pancreáticas
/
Receptor MT1 de Melatonina
/
Melatonina
Limite:
Animals
Idioma:
En
Ano de publicação:
2008
Tipo de documento:
Article