LncRNA-H19 Induces Retinal Müller Cell Apoptosis via MiR-29b/FOXO4 Axis in Diabetic Retinopathy
Background: The pathological development of Diabetic retinopathy (DR) is an intricate process with multiple steps, and implicates a battery of dysregulated genes and regulators. We aimed to investigate the pathological mechanism of DR involving the regulatory association among H19, miR-29b and FOXO4.
Methods: Sprague-Dawley (SD) rats were used to establish the diabetes mellitus (DM) model by injection streptozotocin. The levels of miR-29b, H19 and the mRNA level of FOXO4 were detected by qRT-PCR. The expression of FOXO4 at protein level was assessed by Western blot assay. The apoptosis of rMC-1 cells were analyzed by flow cytometry. To further investigate the relationship between H19 and miR-29b, the RIP and pull down assays were performed.
Results: The expression of H19 and FOXO4 were enhanced obviously, and the level of miR-29b was decreased in the retina tissues of DM rats and high glucose (HG)-treated rMC-1 cells. HG, as well as over-expression of H19, stimulated the apoptosis of rat retinal Müller cells. Knockdown of H19 reversed HG stimulation on cell apoptosis and FOXO4 up-regulation. RIP assay and RNA pull-down assay indicated that H19 was a target of miR-29b and inhibition of miR-29b reversed H19 down-regulation effect on cell apoptosis and FOXO4 expression. Down-regulation of FOXO4 reversed the effect of miR-29b knockdown on cell apoptosis.
Conclusion: MiR-29b targeting lncRNA-H19 mediates the apoptosis of rat retinal Müller cells via regulating FOXO4 in diabetic retinopathy.
Key words: LncRNA-H19, miR-29b, FOXO4, Retinal Müller cell apoptosis, Diabetic retinopathy