Convergencia de vías de señalización en un modelo de apoptosis

Abstract

Sepsis is a generalized inflammatory event induced by the damage produced by an infectious agent. The pathogen most commonly associated with sepsis is Staphylococcus aureus, responsible for the induction of apoptosis in endothelial cells due to the production of ceramide. It has been previously described the protective effect of activated protein C (APC) in sepsis and its relation to the reduced apoptosis of endothelial cells. In this work, the activation of AKT, ASK1, SAPK / JNK and p38 kinase, in a model of endothelial apoptosis, was analyzed using the techniques of Western Blotting and ELISA. Endothelial cells (EA.hy926), were treated with C2-ceramide (130μM) in the presence of chemical inhibitors of each of these kinases and PCA. The survival of the cells in the presence of chemical and PCA inhibitors was evaluated by fluorescent assays of the activation of caspases 3, 7 and 9. The results showed that the ceramide reduced AKT activation and increases activation of ASK, SAPK / JNK and p38 kinases, whereas PCA exerts the opposite effect. Additionally, it was found that the thioredoxin increases the activation / phosphorylation of AKT, whereas p38 kinase induces AKT dephosphorylation.