Effect of Platelet-Rich Fibrin (PRF) Membrane on the Expression of Matrix Metalloproteinase 9 (MMP-9) and Tissue Inhibitor of Metalloproteinase 1 (TIMP-1) in Corneal Wound Healing: Pseudomonas aeruginosa Keratitis

Background: Pseudomonas aeruginosa is the most common cause of bacterial keratitis, with potential complications such as corneal perforation and endophthalmitis. Platelet-rich fibrin (PRF) membrane is utilized as a treatment for corneal ulcers. Maintaining a balance between collagen formation and extracellular matrix remodeling is crucial in fibrosis, a process regulated by matrix metalloproteinases (MMPs) and Tissue Inhibitors of Matrix Metalloproteinases (TIMPs). This study aims to analyze the effect of the PRF membrane on the expression of MMP-9 and TIMP-1 in keratitis.Methods: This study employed an experimental design with a randomized posttest-only control group. New Zealand white rabbits (Oryctolagus cuniculus) were used as animal models with Pseudomonas aeruginosa keratitis. Levofloxacin eye drops were administered to both the control and treatment groups. However, in the treatment group, a PRF membrane was sutured. The expression of MMP-9 and TIMP-1 was compared between the two groups.Results: The animal models consisted of 12 New Zealand white rabbits, divided into a control group and a treatment group, each comprising 6 rabbits. The mean ± SD of MMP-9 in the treatment group was 2.58 ± 0.72, whereas in the control group, it was 4.62 ± 1.56. TIMP-1 data in the treatment group had a median of 4.10 (with a minimum of 2.00 and a maximum of 4.80), while in the control group, it was 4.80 (with a minimum of 4.20 and a maximum of 8.96). Analysis using the independent t-test and Mann-Whitney test revealed substantial disparities in the expression levels of MMP-9 and TIMP-1 between the control and treatment groups, with p-values of 0.016 and 0.036, respectively. The treatment group exhibited a lower expression of MMP-9 compared to the control group, whereas the treatment group demonstrated a higher expression of TIMP-1 in comparison to the control group.Conclusion: PRF membranes can modulate MMP-9 expression and the balance between MMP-9 and TIMP-1 in degrading and depositing the extracellular matrix (ECM). They can be considered as an option for cases of Pseudomonas aeruginosa keratitis to reduce corneal scarring.