Abstract
Purpose :
Blue-light (BL) from the Light-emitting diode (LED) causes oxidative stress in the retina, results in harmful effects on the eyeball. The major cell types of retina, neuro-retinal cells and glial cells play crucial roles in retinal degeneration induced by BL. In this study, we investigated whether crystallins and miR-325-3p are pivotal regulators in neuro-retinal cell under BL irradiation.
Methods :
R-28 cells and retina of rats were exposed to wavelength 460 nm and strength 2000 lux using LED chamber, and cells and retinal tissue were collected after incubation. MTT (3-(4,5-Dimethylthiazol-2-yl) assay was performed for analysis of BL-induced retinal cell viability, and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay was conducted to analyze cell apoptosis of retinal tissue. RT-qPCR and Western immunoblotting were performed to confirm the expressions of RNA and protein, respectively. EGFP-reporter analysis carried out to determine whether miR-325-3p regulates crystallins mRNA by targeting its binding sites.
Results :
BL exposure group showed decreased cell viability of R-28 cells compared to the control group and increased apoptotic retinal cells of rats. The mRNA levels of Cryaa and Crybb3 were significantly reduced in the BL-induced retinal degeneration (RD) group, whereas level of miR-325-3p increased. EGFP reporter expressions (having each 3’UTR of Cryaa and Crybb3) were down-regulated by ectopic expression of miR-325-3p, whereas control EGFP reporter (EGFP-Cl) was not affected by miR-325-3p. On the contrary, inhibition of miR-325-3p up-regulated both EGFP expressions.
Conclusions :
In this study, we shown that BL exposure induces apoptotic of neuro-retinal cell death in both cell line and rat model. Moreover, BL-induced miR-325-3p leads to attenuate expressions of Cryaa and Crybb3, playing a protective role in cells. Our results suggest that molecular axis between miR-325-3p and crystallins (Cryaa and Crybb3) has an essential role in BL-induced retinal degeneration. Therefore, targeting miR-325-3p and crystallins might be able to protect retinal degeneration by BL.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.