Long non-coding RNA GAS5 contributed to the development of glaucoma via regulating the TGF-β signaling pathway

We aimed at discussing the biological function of lncRNA GAS5 (Growth Arrest Specific 5) on the proliferative, apoptotic and differentiative abilities of retinal ganglion cells.

GAS5 expression was knocked down by transfection with siRNA targeting GAS5 (siGAS5) in retinal ganglion cells. After transfection, qRT-PCR was utilized to evaluate the mRNA level of GAS5 expression. The protein levels of smad2 and smad3 were detected by Western blot. Proliferative ability was accessed by Cell Counting Kit-8 (CCK-8) assay, and apoptosis and cell cycle changes were tested by flow cytometry. Also, the differentiative ability of RGC-5 cells was evaluated. TGF-β was exogenously administered to test its function on regulation of GAS5.

Knockdown of GAS5 promoted the cell proliferation and differentiation, but negatively regulated cell apoptosis, and had no effect on cell cycle. Exogenous administration of TGF-β could decrease the expression level of GAS5 in a dose-dependent manner. Meanwhile, lowly expressed GAS5 could improve the phosphorylation of smad2 and smad3.

In our study, we found that down-regulation of lncRNA GAS5 may maintain retinal ganglion cell survival in glaucoma through the activation of TGF-β pathway to promote cell proliferation and differentiation.