Figure 4 of Layton, Mol Vis 2006; 12:43-54.


Figure 4. Mechanisms of changes to FGF-2 and GFAP expression

The effect of insulin-like growth factor and the insulin like growth factor receptor 1 antagonist AG1024 was measured on retinal pigment epithelium (RPE) fibroblast growth factor-2 (FGF-2) expression and Müller cell GFAP expression in culture. Treatment with 9 nM insulin increases FGF-2 production in this system, and this effect is mirrored by 1 nM IGF. A: Expression of FGF-2 by cultured retinal pigment epithelium (RPE) cells after 24 h of treatment. The two effects are not statistically different. Treatment with 30 μM AG1024, a dose effective in blocking IGFR-1 receptors but not insulin receptors [46], reduces both insulin, and IGF-induced FGF-2 expression to levels which are not significantly different to baseline in the 15 mM glucose environment. Addition of 120 μM AG1024, a dose which affects both IGFR-1, and insulin receptors [46] has no additional effect in blocking insulin induced FGF-2 expression. B: Expression of GFAP in cultured Müller cells (RMC) after 24 h of treatment. 9 nM insulin decreases GFAP production in this system and this effect is also evident in cultures treated with 1 nM IGF. The effects of 9 nM insulin and 1 nM IGF are not statistically different. AG1024 (30 μM) blocks the effect of insulin and IGF on GFAP expression to levels that are not significantly different to insulin-free baseline in the 15 mM glucose environment. Addition of 120 μM AG1024 has no additional effect in blocking the action of insulin on GFAP expression in an environment of 15 mM glucose. Asterisk indicates p<0.05 comparison to 15 mM glucose baseline by Student's unpaired t-test with five independent repetitions for each culture treatment.

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Layton, Mol Vis 2006; 12:43-54 <http://www.molvis.org/molvis/v12/a5/>
©2006 Molecular Vision <http://www.molvis.org/molvis/>
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