IGF-1 vs insulin: respective roles in modulating sodium transport via the PI-3 kinase/Sgk1 pathway in a cortical collecting duct cell line

Détails

ID Serval
serval:BIB_E18F4AEA6EC9
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Titre
IGF-1 vs insulin: respective roles in modulating sodium transport via the PI-3 kinase/Sgk1 pathway in a cortical collecting duct cell line
Périodique
Kidney International
Auteur(s)
Gonzalez-Rodriguez  E., Gaeggeler  H. P., Rossier  B. C.
ISSN
0085-2538
Statut éditorial
Publié
Date de publication
01/2007
Peer-reviewed
Oui
Volume
71
Numéro
2
Pages
116-25
Notes
Journal Article
Research Support, Non-U.S. Gov't --- Old month value: Jan
Résumé
Insulin and insulin-like growth factor 1 (IGF-1) may play a role in the regulation of sodium balance by increasing basal and aldosterone-stimulated transepithelial sodium transport in the aldosterone-sensitive distal nephron (ASDN). As insulin and IGF-1 are capable of binding to each other's receptor with a 50- to 100-fold lower affinity than to their cognate receptor, it is not clear which receptor mediates its respective sodium transport response in the ASDN. The aim of the present study was to characterize the IGF-1 regulation of Na(+) transport in the mCCD(cl1) cell line, a highly differentiated cell line which responds to physiological concentrations (K(1/2)=0.3 nM) of aldosterone. IGF-1 increased basal transepithelial Na(+) transport with a K(1/2) of 0.41+/-0.07 nM. Insulin dose-response curve was displaced to the right 50-fold, as compared to that of IGF-1 (K(1/2)=20.0+/-3.0 nM), indicating that it acts through the IGF type 1 receptor (IGF-1R). Co-stimulation with IGF-1 (0.3 nM) (or 30 nM insulin) and aldosterone (0.3 nM), either simultaneously or by pretreating the cells for 5 h with aldosterone, induced an additive response. The phosphatidylinositol-3' kinase (PI3-K) inhibitor LY294002 completely blocked IGF-1 and aldosterone induced and co-induced currents. As assessed by Western blotting, protein levels of the serum-, and glucocorticoid-induced kinase (Sgk1) were directly and proportionally related to the current induced by either or both IGF-1 and aldosterone, effects also blocked by the PI3-K inhibitor LY294002. IGF-1 could play an important physiological role in regulating basal sodium transport via the PI3-K/Sgk1 pathway in ASDN.
Mots-clé
1-Phosphatidylinositol 3-Kinase/antagonists & inhibitors/*physiology Aldosterone/pharmacology Animals Cell Line Chromones/pharmacology Immediate-Early Proteins/blood/*physiology Insulin/*physiology Insulin-Like Growth Factor I/*physiology Ion Transport/drug effects Kidney Tubules, Distal/cytology/drug effects/*physiology Mice Morpholines/pharmacology Phosphorylation Protein-Serine-Threonine Kinases/blood/*physiology Sodium/*metabolism
Pubmed
Web of science
Open Access
Oui
Création de la notice
24/01/2008 13:01
Dernière modification de la notice
20/08/2019 16:05
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