The microRNA-7-mediated reduction in EPAC-1 contributes to vascular endothelial permeability and eNOS uncoupling in murine experimental retinopathy

• Verfasst von: García-Morales, Verónica [VerfasserIn]
• Verfasst von: Friedrich, Julian [VerfasserIn]
• Verfasst von: Hammes, Hans-Peter [VerfasserIn]
• Titel: The microRNA-7-mediated reduction in EPAC-1 contributes to vascular endothelial permeability and eNOS uncoupling in murine experimental retinopathy
• Verf.angabe: Veronica Garcia-Morales, Julian Friedrich, Lysanne M. Jorna, Manuel Campos-Toimil, Hans-Peter Hammes, Martina Schmidt, Guido Krenning
• Jahr: 2017
• Umfang: 11 S.
• Illustrationen: Illustrationen
• Fussnoten: Published online: 28 March 2017 ; Gesehen am 21.06.2018 ; DOI eventuell nicht korrekt
• Titel Quelle: Enthalten in: Acta diabetologica
• Ort Quelle: Mailand : Springer, 1991
• Jahr Quelle: 2017
• Band/Heft Quelle: 54(2017), 6, Seite 581-591
• ISSN Quelle: 1432-5233
• DOI: doi:10.1007/s00592-017-0985-y
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1576739376

Abstract

Aims: To investigate the consequences of oxidative stress and hypoxia on EPAC-1 expression during retinopathy. Methods: Oxygen-induced retinopathy was induced in mice and EPAC-1 expression investigated by immunofluorescence. In silico analyses were used to identify a link between EPAC-1 expression and microRNA-7-5p in endothelial cells and confirmed by western blot analyses on cells expressing microRNA-7-5p. In vitro, endothelial cells were either incubated at 2% oxygen or transfected with microRNA-7-5p, and the effects of these treatments on EPAC-1 expression, endothelial hyperpermeability and NO production were assessed. In the Ins2Akita mouse model, levels of EPAC-1 expression as well as microRNA-7-5p were assessed by qPCR. Endothelial nitric oxide synthase was assessed by immunoblotting in the Ins2Akita model. Results: Hypoxia induces the expression of microRNA-7-5p that translationally inhibits the expression of EPAC-1 in endothelial cells, resulting in hyperpermeability and the loss of eNOS activity. Activation of EPAC-1 by the cAMP analogue 8-pCPT-2′-O-Me-cAMP reduced the sensitivity of EPAC-1 to oxidative stress and restored the endothelial permeability to baseline levels. Additionally, 8-pCPT-2′-O-Me-cAMP rescued eNOS activity and NO production. In mouse models of retinopathy, i.e., oxygen-induced retinopathy and the spontaneous diabetic heterozygous Ins2Akita mice, EPAC-1 levels are decreased which is associated with an increase in microRNA-7-5p expression and reduced eNOS activity. Conclusion/Interpretation: In retinopathy, EPAC-1 expression is decreased in a microRNA-7-mediated manner, contributing to endothelial dysfunction. Pharmacological activation of remnant EPAC-1 rescues endothelial function. Collectively, these data indicate that EPAC-1 resembles an efficacious and druggable target molecule for the amelioration of (diabetic) retinopathy. Electronic supplementary material. The online version of this article (doi:10.1007/s00592-017-0985-y) contains supplementary material, which is available to authorized users.