Effects of Subconjunctival Bevacizumab and Ranibizumab on Corneal and Systemic Oxidative Stress Biomarkers in an Alkali Injury Model

The study tests the efficacy of subconjunctival ranibizumab and bevacizumab treatments in determining the oxidant and antioxidant levels during alkali-induced corneal neovascularisation. The researchers assigned 24 New Zealand White rabbits into four different groups, which included a healthy control, an alkali-injured control, a BV-treated group, and an RN-treated group, with six rabbits per group. All animals received alkali injury treatment except for the HC group. The AC group received six doses of subconjunctival saline 24 h after their injury, while the BV group and RN group received one dose of 0.5 mg of their respective treatment. The researchers conducted 14-day assays on normal tissue, blood plasma, and erythrocytes to determine total antioxidant status and total oxidant status. The researchers performed biochemical assays for total antioxidant status TAS and total oxidant status TOS on samples that were collected after the 14-day observation period. The corneal TOS levels increased in all injured groups when matched against the HC group. The RN group showed the highest corneal TOS levels, but the difference between the RN and AC and BV groups did not reach statistical significance. The injured groups showed higher corneal TAS levels than HC (<i>p</i> = 0.002), but the AC, BV, and RN groups showed no differences. The injured groups showed a significant decrease in erythrocyte TAS compared with HC (<i>p</i> < 0.001), but the injured groups showed lower plasma TOS levels than HC (<i>p</i> < 0.001). The researchers found no other systemic differences between the groups that received anti-VEGF treatment. The study results show that alkali injury leads to both local and systemic changes in redox status. The two anti-VEGF agents caused numerical changes in corneal oxidative parameters, but these changes did not achieve statistical significance. The research requires further investigation to understand potential agent-related effects on corneal redox balance, which should take place in larger, more detailed studies.