The proliferation of Tenon’s capsule fibroblasts after glaucoma filtration surgery is a harmful element for operation failure. However, the underlying mechanism remains unclear. In this study, we evaluated the role of long non-coding RNA (lncRNA)-MEG3 in the proliferation of Glaucoma Tenon’s capsule fibroblasts (GTFs) with a model of transforming growth factor-β (TGF-β)-induced proliferation which has been used in previous studies to explore the mechanism underlying glaucoma surgery failure.

In vitro cell proliferation model was made by TGF-β2 (5ng/mL)-stimulated GTFs obtained from patients with glaucoma filtration surgery, and cell viability and cell proliferation was assessed by MTT assay and [3H] thymidine incorporation assay respectively. Relative expression of MEG3 and Nrf2 mRNA was determined by quantitative real-time PCR. Nrf2 protein level was detected by western blot. Functional interaction between MEG3 and Nrf2 was examined by RNA pull down and RNA Binding Protein Immunoprecipitation (RIP).

As detected in isolated Tenon’s capsule fibroblasts, expression level of both MEG3 and Nrf2 is decreased in GTFs compared with control fibroblasts (HTFs). Adenovirus mediated overexpression of MEG3 attenuates cell ability and cell proliferation, as well as contributed to upregulation of Nrf2 protein in TGF-β2-stimualted GTFs. MEG3 positively affects the expression of Nrf2 protein rather than Nrf2 mRNA. We found that this functional interaction of them depends on MEG3-Nrf2 protein formation by RNA pull down and RIP analysis and also is proved to be involved in TGF-β2-induced cell proliferation.

The above data suggested that the functional interaction between lncRNA-MEG3 and Nrf2 constitutes the mechanism by which TGF-β2 induces Tenon’s capsule fibroblasts proliferation after glaucoma filtration surgery via the direct binding of MEG3 to Nrf2.