The peroxynitrite donor 3-morpholinosydnonimine activates Nrf2 and the UPR leading to a cytoprotective response in endothelial cells

Autor: Laurine, Mattart, Damien, Calay, Dorothy, Simon, Laura, Roebroek, Laura, Roebroeck, Ludmilla, Caesens-Koenig, Martine, Van Steenbrugge, Virginie, Tevel, Carine, Michiels, Thierry, Arnould, Karim Zouaoui, Boudjeltia, Martine, Raes
Jazyk: angličtina
Rok vydání: 2012
Předmět:
Zdroj: Cellular Signalling. 24(1):199-213
ISSN: 0898-6568
Popis: Endothelial dysfunction is associated with the formation of peroxynitrite, described to be toxic. Recent data also suggests that peroxynitrite is able to activate the protective Nrf2 pathway and/or the unfolded protein response (UPR). The aim of our work was to study the response of human endothelial cells to 3-morpholinosydnonimine (SIN-1), a peroxynitrite donor, and to highlight the possible protective roles of Nrf2 or the UPR pathway in this response. Immortal and primary human umbilical vein endothelial cells were exposed to SIN-1. SIN-1 incubation led to Nrf2 activation and to the overexpression of Nrf2-regulated genes, heme oxygenase-1 (HO-1) and NAD(P)H quinone oxidoreductase 1. We also demonstrated that this defensive response protected cells against cell death induced by serum starvation, by reducing apoptosis (monitored by caspase-3 activity and DNA fragmentation) and favoring autophagosome formation, as evidenced by LC3-II accumulation. Interestingly, we observed an activation of the UPR, with a rapid and significant overexpression of CHOP in serum starved cells stimulated with SIN-1. While siRNA mediated knockdown of CHOP had no effect on DNA fragmentation, the invalidation of Nrf2 or HO-1 by siRNA strongly increased DNA fragmentation, but also reinforced the SIN-1-induced LC3-II accumulation. This study shows that peroxynitrite, at least at sublethal concentrations and within a narrow concentration range, could exert protective effects on endothelial cells by modulating the balance between autophagy and apoptosis, through Nrf2-dependent pathways.
Databáze: OpenAIRE