Investigating the histomorphometric changes of rabbit cornea after infection with Pseudomonas Aeruginosa and treatment with cold plasma.

Abstract

INTRODUCTION: Pseudomonas aeruginosa-caused ocular infections are dangerous since they can cause corneal inflammation, damage, and blindness. This work aims to carefully assess the histomorphometric and clinical changes in rabbit corneas caused by Pseudomonas aeruginosa infection, focusing on investigating the potential therapeutic benefits of cold plasma. MATERIALS AND METHODS: The right eye served as an untreated control, and the animals were randomly divided into four groups: Hariprasad et al. (2008) [1] Control group (the left eye infected with P. aeruginosa); Statham et al. (2008) [2] Antibiotic-treated group; Chaudhry (2013) [3] Non-infected plasma group; and (Speaker et al., 1991 [4]) Infected plasma-treated group. Exams of the left eye were performed on twenty rabbits, divided into four groups: non-infected plasma treatment, plasma-treated infection, plasma-treated infection, and antibiotic-treated infection. Clinical factors were quantified by an ophthalmologist using pre-established scoring systems. Evaluations were conducted on keratocyte expression levels, keratocyte cell count, and histomorphometric indices. Additionally, ELISA tests were used to measure the levels interleukin-6, and C-reactive protein and colony count assays were used to quantify bacteria. HMOX-1 and NRF-2 gene expressions were examined using a real-time PCR technique. RESULTS: A higher frequency of clinical markers, such as tear production, destruction of the eyelid margin, abnormalities, swelling, viscous secretions, corneal swelling, stromal edema, shortened distance between the eyelid margins, corneal hyperemia, intraocular bleeding, and conjunctival inflammation, was noted in the control group. All evaluated clinical indicators were dramatically reduced by both the plasma and antibiotic treatments. Histomorphometric analysis showed significant differences in keratinocyte levels, corneal endothelium, and epithelial thickness between the treatment groups and the control group. The control group's lymphocyte count and stromal layers were notably different from those of the other groups. Plasma treatment significantly raised keratinocytes and the thickness of the cornea's endothelial and epithelial layers while simultaneously lowering the number of lymphocytes and stromal layers. When compared to the infected control, the NRF-2 gene expression in the groups treated with plasma and antibiotics showed a notable decrease, with the plasma-treated group showing the most significant decline. Similarly, both the plasma- and antibiotic-treated groups' HMOX-1 gene expression showed a significant decline, with the plasma-treated group showing the largest decline. The group receiving plasma therapy had a considerable increase in keratinocyte expression. Furthermore, bacterial count, C-reactive protein, and interleukin-6 concentrations markedly decreased in the plasma treatment group compared to the control group. CONCLUSION: This study highlights how well cold plasma therapy works to reduce the negative consequences of corneal infection. The results validate the anti-inflammatory characteristics of plasma and its capacity to inhibit bacterial growth.