Figure 1. Dominant negative Akt does not inhibit angiogenin's protective effect against MPP+.

A. Western blot demonstrating reduced Akt phosphorylation in SH-SY5Y cells transfected with the K179M DN-Akt construct. Twenty-four hours following transfection of empty pCMV5 vector (pC) or DN-Akt vector (DN), SH-SY5Y cells were treated with Insulin Growth Factor (50 ng/mL). Thirty seconds after Insulin Growth Factor treatment, cell lysates were collected for Western blotting. Actin was used as a loading control. B. Representative Western blot demonstrating reduced caspase-3 cleavage following angiogenin treatment in SH-SY5Y cells transfected with either empty vector or HA-tagged DN-Akt using Amaxa nucleoporation. Twenty-four hours after transfection, cells were pretreated with angiogenin (100 nM). MPP+ (0.75 mM) was then applied with fresh angiogenin for an additional 24 hours prior to collection. HA-tagged DN-Akt expression was comparable among all DN-Akt-transfected conditions. Actin was used as loading control. C. Densitometric quantification of caspase-3 cleavage bands normalized to actin. Results reflect three independent experiments. *p<0.05, ***p<0.001 (One-way ANOVA with Tukey's post-hoc test). Error bars reflect SEM.