Aldosterone inhibits Akt activation and induces apoptosis in rat podocytes / 中华肾脏病杂志

ABSTRACT

Objective To evaluate the effect of ALD on podocyte apoptosis and the possible roles of Akt in ALD-induced apoptosis. Methods The cultured rat podocytes were incubated with increasing concentrations of ALD (10-9~10-5 mol/L) for variable time periods. Apoptosis was evaluated by cell nucleus staining and flow cytometry. RT-PCR was used to examine the expression of mineralocorticoid receptor (MR)and 11 Beta-hydroxysteroid dehydrogenase type 2 (11?-HSD2) mRNA in podocyte. Activation of Akt/PKB was evaluated by performing Akt kinase assay. Results ALD induced podocyte apoptosis in a dose- and time-dependent manner. The proapoptotic effect was attenuated by the presence of spironolactone (10-7mol/L). The expression of MR and 11P-HSD2 mRNA was demonstrated in the podocytes by RT-PCR. ALD also inhibited the activity of Akt in a dose-dependent manner, but the inhibitory effect was significantly ameliorated by the presence of spironolactone. The activity of Akt was negatively correlated with podocyte apoptosis. Conclusion ALD induces apoptosis in rat podocytes through the signaling mechanism by which Akt is inhibited.