Figure 4 of Haque, Mol Vis 2017; 23:251-262.


Figure 4. miR-21-regulated SMAD7/SPRY1/PTEN signaling is linked to the activation of pERK and VEGF in ARPE-19 cells under the high glucose condition. Perindopril-treated cells were transfected with scramble control (NG or high glucose), miR-21 mimics (high glucose), or antagomirs of miR-21 (high glucose). Using specific antibodies to SMAD7, SPRY1, PTEN, ERK, and VEGF, the protein/phosphorylation levels were measured with immunoblotting. Compared with scramble NG, a representative western blot (A) and protein analysis (B) showed high glucose-mediated suppression of SPRY1, SMAD7, and PTEN, but increased the activity/expression of ERK and VEGF. Compared with high glucose, miR-21 mimics under high glucose did not show a significant difference at the level of SPRY1, SMAD7, PTEN, and VEGF proteins, as well as the activity of pERK. miR-21 mimics under the high glucose condition did not produce an additional effect compared to high glucose, possibly because the expression of miR-21 is already high in the high glucose condition. The levels of each protein are normalized to that of actin. Values are presented as mean ± standard error of the mean (SEM); n = 3; *p<0.05 versus NG; #p<0.05 versus high glucose control, high glucose and miR-21 mimics.