FIGURE 4.

REDD1 is necessary for the effect of hyperglycemic conditions on VEGF expression. Wild-type and REDD1 knock-out mouse embryonic fibroblasts (MEF) were maintained in 5 mm glucose medium as described above. MEF were exposed to medium containing either 30 mm glucose or 5 mm glucose with 25 mm mannitol as an osmotic control. VEGF protein abundance was assessed by ELISA. The abundance of GAPDH, REDD1, and p70S6K1, and phosphorylation of p70S6K1 on Thr³⁸⁹ were assessed in cell lysates by Western blot. SDS-PAGE was performed using 15% Tris-HCl polyacrylamide gels. Representative blots are shown. B, relative VEGF mRNA abundance was assessed by RT-qPCR. Values are means + S.E. (n = 6). Statistical significance is denoted *, p < 0.05.