Abstract
Abstract: :
Purpose: To evaluate the role of MMPs and their tissue inhibitors (TIMPs) in aqueous humor in patients suffering glaucoma with uveitis compared to cataract controls. Methods: 14 patients with history of prolonged uveitis and secondary glaucoma (5 juvenile rheumatoid athritis, 1 toxoplasma, 1 Fuchs' dystrophy and 7 unknown ethiology were studied. Aqueous humor samples were collected during a glaucoma surgery (Molteno explant). Control samples were collected from 6 patients who underwent a cataract extraction. ECL-Western was performed to measure the levels and molecular forms of MMP-2, -8, -9, -13 and -14 and TIMP-1 and -2 in aqueous humor samples. Results: Compared to controls glaucoma with uveitis expressed clearly elevated amounts of all MMPs. Especially MMP-2, -8, -13 and -14 were highly elevated, but MMP-9 showed moderate upregulation. Interestingly, all MMPs also expressed molecular sizes corresponding the active enzyme forms. ECL-Western additionally revealed that a proportion of MMPs formed complexes with TIMPs. Of the two inhibitors the expression of TIMP-1 was more prominent than TIMP-2 in these samples. Controls contained only faint amounts of all MMPs and both TIMPs and active enzymes forms were not detected. Conclusions: Secondary glaucoma due to uveitis contained increased MMP levels and especially in active forms in aqueous humor. Of the gelatinases (MMP-2 and MMP-9) and TIMPs analyzed, the MMP-2 and TIMP-1 predominated. Increased amounts of MMPs are most probably connected to the activity of the inflammatory component of the disease and gives theoretical possibility to use MMP inhibitors in the treatment of this kind of secondary glaucomas.
Keywords: proteolysis • aqueous • trabecular meshwork