Figure 1.

Periostin stimulates the Akt/mTOR pathway in human ADPKD cells. Primary cyst epithelial cells from human ADPKD kidneys (n=4) were incubated in media containing 250 ng/ml periostin for 15 minutes, or 3 or 24 hours. Levels of (A) phosphorylated Akt (P-Akt) and (B) phosphorylated S6K (P-S6K), a downstream target of mTOR, were determined by immunoblot analysis. Numbers above representative immunoblots are (A) P-Akt/Akt and (B) P-S6K/S6K, normalized to control (set to 1.0). Bar graphs represent the mean and SEM for (A) P-Akt/Akt and (B) P-S6K/S6K from cell preparations from four different ADPKD kidneys. *P<0.05, versus control treatment.