TNFα Inhibits IGFBP-3 through Activation of p38α and Casein Kinase 2 in Human Retinal Endothelial Cells
Figure 1
TNFα increases phosphorylation of p38α to regulate IGFBP-3 levels.
Panel A presents ELISA results for IGFBP-3 following treatment with a non-selective p38 inhibitor (SB202190) and TNFα. Panel B shows Western Blot results of the ratio of phospho-p38α to total p38α with a dose-response curve for BIRB796, a p38α selective inhibitor. Panel C shows Western blot results for the ratio of phosphorylation of p38α to total p38 from REC grown in normal glucose (NG), high glucose (HG), high glucose + TNFα (HG+TNFα), high glucose + p38α inhibitor (HG+BIRB796), and high glucose + TNFα + p38α inhibitor (HG+TNFα+BIRB796). Panel D presents ELISA results for IGFBP-3 in cells treated with the same treatments. *P<0.05 vs. NG, #P<0.05 vs. HG, $P<0.05 vs. HG+TNFα. All data are mean ± SEM. Data is from 3–4 independent experiments for each treatment.