Effect of human lactoferrin solution on histological changes of rabbit cornea in alkaline burns

Abstract

BACKGROUND: Eye burns are a severe injury, accounting for 6.1–38.4% of all ophthalmic diseases. Alkaline burns are the most common and most severe forms of eye burns. AIM: Evaluation of the effectiveness of drug topical application based on human lactoferrin in alkaline cornea burns of the 3rd degree in the experiment. MATERIAL AND METHODS: The study was conducted on 42 rabbits. It included two groups: the first (without treatment) — alkaline burns during therapy with water for injection (1 drop 3 times a day) — 21 rabbits, the second (experimental) — treatment with lactoferrin solution (concentration 2.5 mg/ml, 1 drop 3 times a day) — 21 rabbits. Alkaline burns were induced by applying a filter paper disc moistened with 5% sodium hydroxide solution to the cornea. 6 eyes of 3 intact animals served as controls. The effectiveness of the drug was evaluated by the rate of closure of the corneal epithelium defect, the time of suppression of the inflammatory reaction in the area of the defect and the limbus, the degree of restoration of the morphological structure of the cornea, as close as possible to the normal rabbit cornea. The obtained data were processed using the methods of variation statistics, the Statistica 10.0 software package. The significance of differences was assessed by calculating the median and interquartile interval. The critical level of significance for statistical criteria was taken as p=0.05. RESULTS: From the 3rd day of the study, in the experimental treatment group, there was an acceleration of reepithelialization, restoration of the cornea's own substance, and a more rapid subsidence of inflammation compared to the control group. The thickness of the cornea in the center of the defect in the group without treatment was significantly higher than the values of intact animals at all periods of observation: on the 3rd day after the burn it was 615.99 [450.70–794.07] µm (p=0.000574), reached the maximum by day 7 — it was 1363.16 [907.78–1543.44] µm (p=0.000091), and by day 28 it decreased to 384.38 [376.03–398.14] µm (p=0.0000041). In the group with experimental treatment, the thickness of the cornea in the center of the defect also increased relative to intact animals, starting from the 1st day of pathology, reaching maximum values on the 3rd day — 436.70 [415.57–489.90] µm (p=0.005589). The use of lactoferrin solution in comparison with the first group led to a significant decrease in the thickness of the cornea in the center of the defect on 7th (p=0.039985) and 28th days (p=0.0443). CONCLUSION: Local application of lactoferrin solution in alkaline burns of the cornea promotes faster regeneration of the epithelium and restoration of the stroma structure of the rabbit cornea.