Fig. 4.

Induction of VEGF by AAI goes through SP-1 and HIFs activation. LLC-PK1 cells were transfected with reporter plasmid containing luciferase encoding sequence under the control of VEGF promoter. 24 h after transfection cells were prestimulated with 1 μM mithramycin A (A–C) or 60 nM chetomin (D) for 30 min and then AAI was added for 24 h. The elevation of VEGF promoter activity (A), mRNA level (B) as well as VEGF protein level (C) evoked by AAI was reversed by inhibition of SP-1 activity by mithramycin A. Moreover, inhibition of HIF activity by chetomin caused the reversal effect on AAI-induced VEGF protein level (D). Mean of 3 (A, B, C) or 2 (D) experiments performed in duplicates; *p < 0.05 vs control; ^#p < 0.05 vs AAI-treated cells.