Purchase this article with an account.
M Maatta, H Autio-Harmainen, J Airaksinen; Altered aqueous humor levels of MMP-2 and TIMP-2 in glaucoma . Invest. Ophthalmol. Vis. Sci. 2002;43(13):2458.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Purpose: Matrix metalloproteinases (MMPs) have been previously shown to importantly control the trabecular outflow. We measured the levels of MMP-2 and its inhibitor, tissue inhibitor of metalloproteinases-2 (TIMP-2) in different types of glaucomas and in controls. Methods: The material comprised 25 glaucoma (6 primary open angle glaucomas (POAG), 5 exfoliative glaucomas (EXFG), 3 non-hypertensive glaucomas, 11 glaucomas with uveitis) and 8 cataract samples (controls). MMP-2 and TIMP-2 concentrations were examined by ELISA and MMP-2 activation by zymography. Results: The average concentrations for MMP-2 and TIMP-2 in POAG were 116 and 74 ng/ml (range 86-157 and 36-119), in EXFG 364 and 87 ng/ml (range 240-583 and 46-146), in non-hypertensive glaucoma 72 and 41 ng/ml (range 63-88 and 35-46), in glaucoma with uveitis 348 and 101 ng/ml (range 98-1169 and 44-143) and in controls 43 and 13 ng/ml (range 15-55 and 11-15), respectively. MMP-2 showed statistically significantly higher concentrations in all the different glaucoma types when compared to controls (P= below 0.05). TIMP-2 showed also similar pattern, except in non-hypertensive glaucomas. In zymography 72 kD latent MMP-2 was present in all glaucoma and control samples, but active 62 kD only in 2 glaucomas with uveitis. Conclusion: Significantly higher concentrations of MMP-2 and TIMP-2 are present in different types of glaucomas. However, MMP-2 activation was not simultaneously increased. This fits well with the previous notion that there is an increased extracellular matrix deposition in the trabecular meshwork in glaucoma. The increased expression of MMP-2 may reflect a normal response to the increased matrix deposition in the trabecular area. However, it is also possible that there is an imbalance in the MMP-2 activation and inhibition leading to the increased outflow resistance and elevated intraocular pressure.
This PDF is available to Subscribers Only