PRDX1 exerts a photoprotection effect by inhibiting oxidative stress and regulating MAPK signaling on retinal pigment epithelium.

BACKGROUND: The purpose of this study was to investigate the photoprotection effect of peroxiredoxin 1 (PRDX1) protein in ultraviolet B (UVB) irradiation-induced damage of retinal pigment epithelium (RPE) and its possible molecular mechanism. METHODS: ARPE-19 cell viability and apoptosis were assessed by MTT assay and flow cytometry, respectively. Real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to detect the PRDX1 expression. The corresponding kits were employed to measure the levels or activities of lactate dehydrogenase (LDH), 8-hydroxy-2-deoxyguanosine (8-OHdG), reactive oxygen species (ROS), malondialdehyde (MDA), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD). Western blotting was applied to examine PRDX1 expression and mitogen-activated protein kinase (MAPK) signaling pathway-related proteins. RESULTS: After exposure to 20 mJ/cm2 intensity of UVB irradiation for 24 h, ARPE-19 cells viability was decreased, the leakage degree of LDH and 8-OHdG were increased, and cell apoptosis was elevated. The expression of PRDX1 was significantly down-regulated in UVB-induced ARPE-19 cells. The low expression of PRDX1 was involved in high irradiation intensity. Overexpression of PRDX1 increased cell activity, decreased cell apoptosis, and LDH as well as 8-OHdG leakage in UVB-induced ARPE-19 cells. In addition to alleviating UVB-induced cell damage, PRDX1 overexpression also inhibited UVB-induced oxidative stress (down-regulation of ROS and MDA levels, up-regulation of GSH-Px and SOD activities) and the activation of MAPK signaling pathway in ARPE-19 cells. CONCLUSION: PRDX1 exerts a photoprotection effect on RPE by attenuating UVB-induced cell damage and inhibiting oxidative stress, which can be attributed to the inhibition of MAPK signaling pathway activation.

Recurrent retinal detachment after pars plana vitrectomy with silicone oil tamponade for rhegmatogenous retinal detachment.

BACKGROUND: The recurrence of retinal detachment following rhegmatogenous retinal detachment (RRD) is a relatively common complication that can lead to reduced visual acuity and requires further surgery. The purpose of this study was to investigate the risk factors and visual outcomes of recurrent RRD following pars plana vitrectomy (PPV) with silicone oil tamponade for primary RRD. METHODS: This was a retrospective follow-up study of 343 eyes that underwent initial PPV surgery with silicone oil tamponade for primary RRD. Patients were divided into a recurrence group and a reattachment group. The main outcome measures included causative factors, visual outcomes related to the recurrence of RRD, and the perioperative factors most affecting the recurrence of RRD. RESULTS: After retinal reattachment, we observed RRD recurrence after PPV for primary RRD in 42 out of 343 eyes (12.2%) during the follow-up period. Most causes of recurrence (69%) occurred within 6 months of surgery. Multivariate logistic regression analysis showed that a PVR ≥ Grade C (odds ratio [OR]: 4.015; 95% confidence interval [CI] 1.721-9.367; P = 0.001) was a significant predictor for the development of recurrent RRD. Compared with the reattachment group, the recurrence group exhibited a significant decline in best-corrected visual acuity (BCVA) at the last follow-up visit (P = 0.000). Eyes with PVR prior to primary surgery, or at the diagnosis of re-detachment, showed a worse final BCVA. CONCLUSIONS: Our analysis shows that the predominant risk factor for the recurrence of RRD is a PVR ≥ Grade C. PVR prior to primary surgery, or at the diagnosis of re-detachment, was also shown to limit the recovery of final visual acuity.