The neuroretina is a novel mineralocorticoid target: aldosterone up-regulates ion and water channels in Müller glial cells.

Détails

ID Serval
serval:BIB_3D6B9B80AE6F
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Institution
Titre
The neuroretina is a novel mineralocorticoid target: aldosterone up-regulates ion and water channels in Müller glial cells.
Périodique
Faseb Journal : Official Publication of the Federation of American Societies For Experimental Biology
Auteur⸱e⸱s
Zhao M., Valamanesh F., Celerier I., Savoldelli M., Jonet L., Jeanny J.C., Jaisser F., Farman N., Behar-Cohen F.
ISSN
1530-6860 (Electronic)
ISSN-L
0892-6638
Statut éditorial
Publié
Date de publication
2010
Peer-reviewed
Oui
Volume
24
Numéro
9
Pages
3405-3415
Langue
anglais
Notes
Publication types: Journal Article ; Research Support, Non-U.S. Gov'tPublication Status: ppublish
Résumé
Glucocorticoids reduce diabetic macular edema, but the mechanisms underlying glucocorticoid effects are imperfectly elucidated. Glucocorticoids may bind to glucocorticoid (GR) and mineralocorticoid (MR) receptors. We hypothesize that MR activation may influence retinal hydration. The effect of the MR agonist aldosterone (24 h) on ion/water channel expression (real-time PCR, Western blot, immunofluorescence) was investigated on cultured retinal Müller glial cells (RMGs, which contribute to fluid homeostasis in the retina), in Lewis rat retinal explants, and in retinas from aldosterone-injected eyes. We evidenced cell-specific expression of MR, GR, and 11-beta-hydroxysteroid dehydrogenase type II. Aldosterone significantly enhances expression of sodium and potassium channels ENaC-alpha (6.5-fold) and Kir4.1 (1.9-fold) through MR and GR occupancy, whereas aquaporin 4 (AQP4, 2.9-fold) up-regulation is MR-selective. Aldosterone intravitreous injection induces retinal swelling (24% increase compared to sham-injected eyes) and activation of RMGs. It promotes additional localization of Kir4.1 and AQP4 toward apical microvilli of RMGs. Our results highlight the mineralocorticoid-sensitivity of the neuroretina and show that aldosterone controls hydration of the healthy retina through regulation of ion/water channels expression in RMGs. These results provide a rationale for future investigations of abnormal MR signaling in the pathological retina.
Mots-clé
Aldosterone/pharmacology, Animals, Aquaporin 4/genetics, Aquaporin 4/metabolism, Blotting, Western, Cell Line, Cells, Cultured, Dexamethasone/pharmacology, Epithelial Sodium Channels/genetics, Epithelial Sodium Channels/metabolism, Female, Fluorescent Antibody Technique, Gene Expression/drug effects, Gene Expression/genetics, Humans, Immunohistochemistry, Polymerase Chain Reaction, Potassium Channels, Inwardly Rectifying/genetics, Potassium Channels, Inwardly Rectifying/metabolism, Rats, Rats, Inbred Lew, Receptors, Glucocorticoid/genetics, Receptors, Glucocorticoid/metabolism, Receptors, Mineralocorticoid/genetics, Receptors, Mineralocorticoid/metabolism, Retina/cytology, Retina/metabolism
Pubmed
Web of science
Création de la notice
23/08/2013 7:40
Dernière modification de la notice
20/08/2019 13:33
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