MiR-205-3p protects human corneal epithelial cells from ultraviolet damage by inhibiting autophagy via targeting TLR4/NF-κB signaling.

OBJECTIVE: MiRNA has been found to have therapeutic effect on corneal damage. This paper aimed to study the effect of miR-205-3p on corneal damage induced by ultraviolet (UV) radiation. MATERIALS AND METHODS: HCE cell were exposed to UV light and transfected. Quantitative Real Time-Polymerase Chain Reaction (qRTPCR) and Western blot were used to determine miRNA/mRNA and protein expression. CCK-8 assay, Edu incorporation experiment, and flow cytometry were used to separately measure cell activity, proliferation and apoptosis. LC3 puncta were researched by immunofluorescence experiment. TNF-a, IL-6 and IL-1ß levels in cells were detected by enzyme-linked immunosorbent assay (ELISA) kit. MDA, SOD, and GSH-PX levels were measured using detection kits. Reactive oxygen species (ROS) level was reflected by detecting DCFH-DA density. Luciferase activity assay was performed to verify the regulating relationship between miR-205-3p and TLR4. RESULTS: UV radiation decreased HCE cell viability, proliferation, and increased HCE cell apoptosis and autophagy (all p < 0.01). When exposed UV radiation, the overexpression of miR- 205-3p group elevated HCE cells viability, proliferation and weakened HCE cells apoptosis and autophagy (all p < 0.01). MiR-205-3p inhibited inflammation and oxidative stress in HCE cells induced by UV radiation (p < 0.01). MiR-205-3p directly inhibited TLR4 expression. The upregulation of TLR4 significantly reversed the effects of miR-205-3p on HCE cell phenotypes induced by UV radiation (p < 0.01). CONCLUSIONS: MiR-205-3p protected HCE cells from UV damage by inhibiting autophagy via targeting TLR4. [ABSTRACT FROM AUTHOR]