Rosiglitazone Inhibited Aldosterone-Induced Mesangial Cell Proliferation via Blocking Phosphatidyl Inositol 3-Kinase Activation

Objective To explore the inhibitory effect of rosiglitazone of peroxisome proliferator-activated receptor-γ(PPARγ) agonist on aldosterone-induced mesangial cell(MC) proliferation.Methods Mouse primary MC were cultured and treated with aldosterone(100 nmol/L) in the presence or absence of rosiglitazone(1.0,2.5,5.0,10.0 μmol/L).The incorporation of 3H-thymidine(3H-TdR) and cell count were used as the measure of MC proliferation.Cyclin D1 and cyclin A expression,PI3K and Akt phosphorylation were determined by Western blot analysis.Results 1.Aldosterone induced MC proliferation,as assessed by 3H-TdR incorporation and cell number,which were increased by 2.46-and 2.14-fold,respectively,in aldosterone-treated cells.Aldosterone-induced MC proliferation was inhibited by PPARγ agonist rosiglitazone in dose-dependent manner in mouse MC.2.Aldosterone induced cyclin D1 and cyclin A expression.Rosiglitazone reduced aldosterone-induced cyclin D1 and cyclin A expression in dose-dependent manner.3.Aldosterone induced PI3K/Akt activation in dose-dependent manner,incubation with 100 nmol/L aldosterone for 60 min,phosphorylation PI3K and Akt expression increased by above 3.0-fold.4.PI3K inhibitor LY294002 and Akt inhibitor significantly inhibited aldosterone-induced cyclin D1 and cyclin A expression.5.Rosiglitazone significantly inhibited aldosterone-induced PI3K/Akt activation,10 μmol/L rosiglitazone almost completely blocked aldosterone-induced PI3K/Akt activation.Conclusion Rosiglitazone can block aldosterone-induced MC proliferation via inhibition of PI3K/Akt activation.