Enying Jiang

Dry eye disease (DED) is characterized by tear film instability and oxidative stress-induced epithelial damage. This study was conducted to compare the therapeutic effects of 2% rebamipide (REB) and 3% diquafosol (DQS) on oxidative stress-related apoptotic damage of the ocular surface in DED. Human corneal epithelial cells (HCECs) were exposed to hyperosmotic stress in vitro and treated with REB or DQS. Cell viability and cleaved caspase-3 expression were evaluated using the MTT assay and Western blotting. DED was induced in vivo in C57BL/6 mice using subcutaneous scopolamine injection. Thereafter, the mice were assigned to normal control (NC), dry eye (DE), DQS-treated (DQS), or REB-treated (REB) groups. Clinical evaluations, including measurement of tear film break-up time, corneal smoothness, and the lipid layer, were performed on days 7 and 14. In addition, CD4⁺ IFN-γ⁺ T cells, inflammatory cytokines, reactive oxygen species (ROS), lipid peroxidation markers, and corneal apoptosis were analyzed on day 14. Glycocalyx integrity and goblet cell density were also evaluated. The results indicate that REB improved HCEC survival and suppressed cleaved caspase-3 expression more effectively than DQS (p < 0.05). Both treatments improved clinical outcomes in the murine dry eye model; however, REB showed superior efficacy in reducing ROS levels, lipid peroxidation, and apoptosis, and in preserving corneal glycocalyx integrity and conjunctival goblet cell density. These findings highlight the therapeutic potential and protective effects of REB against oxidative stress-related damage and apoptosis in DED.

Background/Objectives: This study aimed to evaluate the therapeutic effects of combined 5% lifitegrast (LF) and tocopherol (TCP) eye drops in a murine experimental dry eye (EDE) model. Methods: Female C57BL/6 were divided into seven groups: untreated controls, EDE control, EDE + 0.05% cyclosporin A (CsA), EDE + tocopherol (TCP), EDE + 5% LF, EDE + 5% LF + TCP (once daily), and EDE + 5% LF + TCP (twice daily). Clinical parameters (tear volume, tear break-up time (TBUT), corneal fluorescein staining score (CFSS), tear film lipid layer grade (TFLLG)) were assessed on days 7 and 14. Goblet cell density in the conjunctiva, CD4+ IFN-γ+ T cells, interleukin levels, reactive oxygen species (ROS) levels, and corneal apoptotic cells were analyzed on day 14. Results: Monotherapy with 0.05% CsA and LF showed improvements in all clinical parameters compared to the EDE control (p < 0.05). Combination therapy groups demonstrated superior improvements in clinical parameters compared to the EDE control, 0.05% CsA, and 5% LF groups. CD4+ IFN-γ+ T cell percentages and ROS levels in the cornea and conjunctiva were markedly reduced in the combination groups compared with the 0.05% CsA and 5% LF groups (p < 0.01). Furthermore, corneal apoptotic cells significantly decreased in the combination groups compared to the 0.05% CsA and TCP groups (p < 0.05). Conclusions: Combined 5% LF and TCP eye drops improved tear film parameters and reduced inflammatory and oxidative stress markers. The combination therapy can mitigate ocular surface damage by managing inflammation and oxidative stress in dry eye.

This study aims to investigate the effect of the selective MT2 receptor agonist, IIK7, on corneal autophagy and apoptosis, aiming to reduce corneal epithelial damage and inflammation from blue light exposure in mice. Eight-week-old C57BL/6 mice were divided into BL-exposed (BL) and BL-exposed with IIK7 treatment (BL + IIK7 group). Mice underwent blue light exposure (410 nm, 100 J) twice daily with assessments at baseline and on days 3, 7, and 14. Corneal samples were analyzed for MT2 receptor expression, autophagy markers (LC3-II and p62), and apoptosis indicators (BAX expression and TUNEL assay). Then, mice were assigned to normal control, BL, and BL + IIK7. Ocular surface parameters, including corneal fluorescein staining scores, tear volume, and tear film break-up time, were evaluated on days 7 and 14. On day 14, reactive oxygen species (ROS) levels and CD4⁺ IFN-γ⁺ T cells percentages were measured. The BL group exhibited higher LC3-II and p62 expression, while the BL + IIK7 group showed reduced expression (p < 0.05). The TUNEL assay showed reduced apoptosis in the BL + IIK7 group compared to the BL group. ROS levels were lower in the BL + IIK7 group. The BL + IIK7 group showed improved ocular surface parameters, including decreased corneal fluorescein staining and increased tear volume. The percentages of CD4⁺ IFN-γ⁺ T cells indicated reduced inflammatory responses in the BL + IIK7 group. The MT2 receptor agonist IIK7 regulates corneal autophagy and apoptosis, reducing corneal epithelial damage and inflammation from blue light exposure.