Inhibition of Aberrant IGF-I Signaling in Diabetic Male Rat Retina Prevents and Reverses Changes of Diabetic Retinopathy

Figure 1

Anti-IAP antibody prevents IGF-I-stimulated SHPS-1/IAP association and SHPS-1 tyrosine phosphorylation. (a) Rat endothelial cells were grown to confluency in normal glucose (NG, 5 mM) or high glucose (HG, 25 mM) medium. Cells were exposed to serum containing growth medium before being harvested. (b, c) Cells were grown to confluency in HG medium, then placed in serum-free HG medium. The indicated concentrations of anti-IAP antibody were incubated with the cells for 2 h, and IGF-I (100 ng/ml) was incubated for 10 min before the cells were harvested. Cell lysates were immunoprecipitated with an anti-SHPS-1 antibody and immunoblotted with an anti-IAP antibody (a, b) or an anti-pY99 antibody (c). The same amount of cell lysate was immunoblotted with an anti-SHPS-1 antibody as a loading control. Each experiment was repeated 3 times, and the results were similar to the representative immunoblots shown in the figures. The bar graph shows the of scanning densitometry values of SHPS-1-associated IAP (a, b) or phospho-SHPS-1 (c) divided by total SHPS-1. and indicate the significant differences.

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