Expressions of Matrix Metalloproteinase-3 and Tissue Inhibitor Metalloproteinase-1 in Corneal Tissue Post Alkali Burn Treated with Topical Medroxyprogesterone Acetate and Doxycycline

Purpose: This study aims to investigate the effects of topical Medroxyprogesterone acetate (MPA) and Doxycycline in inhibiting the expression of MMP-3 and TIMP-1 in ocular alkali burn models in animals. Methods: A total of 18 New Zealand Rabbits were divided into 3 groups based on their post-alkali-burn treatment: PBS (G1/ control group), topical Doxycycline 1mg/ml (G2), and topical MPA 1% (G3). Alkali burn models were made by exposing 1N NaOH solution to the central cornea for 30 seconds. MMP-3 and TIMP-1 expression were evaluated using immunohistochemistry after 14 days of treatment. Results: Statistically significant differences in the mean MMP-3 expression were found between the three groups (p=0.010). There was a significant difference in MMP-3 expression between the control group with MPA (p=0.017) and Doxycycline (p=0.028) but was not found between the MPA and Doxycycline groups (p=1,000). The mean differences in TIMP-1 expression between the three treatment groups were statistically significant (p=0.005), with a significant difference between the control group with Doxycycline (p=0.022) and MPA (p=0.007). There was no significant difference in TIMP-1 expression between the Doxycycline and MPA groups (P=1,000). Conclusion: This study indicated that topical administration of Doxycycline or MPA in ocular alkali burn reduces the expression of MMP-3 and TIMP-1.