[Effects of blocking activation of IGF-1-Stat3 signaling pathway in guinea pig sclera fibroblast by AG490 on expression of MMP-2 and Integrinβ(1)].

Objective: To explore the effect of Blocking activation of IGF-1-Stat3 signaling pathway in guinea pig sclera fibroblast (GSFs) by AG490 on expressions of MMP-2, Integrinβ(1).

Methods: Cultured GSFs were divided into four groups: group A(control group: only DMEM without IGF-1), group B (only IGF-1 group), group C(IGF-1 + PBS group), group D (IGF-1 + 25 µmol/L AG490 group). The expressions of Stat3, p-Stat3, MMP-2, Integrinβ(1) protein induced by IGF-1 and inhibited by AG490 in GSFs were detected by Western blot. The levels of Stat3, MMP-2 and Integrinβ(1)mRNA were detected by RT-PCR.

Results: Compared with Groups A and D, Stat3, p-Stat3, MMP-2 protein expression in groups B and C were expressed at higher level (t(pr) = -32.324, -26.284, -32.876, -26.345, -68.668, -58.724, -187.481, -58.842, -110.264, -120.256, -121.345, -120.286; t(mRNA) = -31.554, -31.178, -31.286, -31.198, -12.076, -14.969, -11.896, -14.546, P < 0.05), but the expression levels were not obviously different between groups B and C (t(p) = -32.720, -32.816, -68.668, -187.481, -110.264, -121.345; t(mRNA) = -0.692, -0.579, P > 0.05), which were similar to mRNA level. The Integrinβ(1) protein and mRNA were expressed in groups A, B, C and D but no significant difference among them respectively (F(pr) = 0.214;F(mRNA) = 0.045, P > 0.05).

Conclusions: Activation of Stat3 signaling pathway may be involved in up-modulating the expression of MMP-2 in GSFs, and not affect the Integrinβ(1) protein and mRNA changes. The results reveal that Stat3 signaling transduction pathway may play a critical role in sclera remodeling by means of modulating MMP-2 expression.