| First Author | Robertson JV | Year | 2013 |
| Journal | Mol Vis | Volume | 19 |
| Pages | 684-95 | PubMed ID | 23559862 |
| Mgi Jnum | J:196164 | Mgi Id | MGI:5486620 |
| Citation | Robertson JV, et al. (2013) Altered expression of transforming growth factor beta 1 and matrix metalloproteinase-9 results in elevated intraocular pressure in mice. Mol Vis 19:684-95 |
| abstractText | PURPOSE: Extracellular matrix remodeling is thought to have profound effects on tissue architecture and associated function. We have shown previously that overexpression of transforming growth factor beta (TGFbeta), which stimulates matrix accumulation, results in altered morphology, cataract, and ocular hypertension in rodents. We have further shown that TGFbeta-induced cataracts can be mitigated through inhibition of the matrix metalloproteinases (MMP) MMP-2 and MMP-9. We therefore sought to determine whether loss of MMP expression also altered TGFbeta-induced changes in intraocular pressure (IOP). METHODS: To carry out this study, TGFbeta1 transgenic mice were bred onto a MMP-9 null background. IOP measurements were made at 1- to 2-, 2- to 3-, and 3- to 4-month time points using a TonoLab rebound tonometer. Histological and immunofluorescence findings were obtained at the same time points. RESULTS: Our results demonstrate that lens-specific expression of TGFbeta1 in mice results in altered morphology of the anterior segment and an accompanying significant increase in IOP. TGFbeta1 transgenic mice bred onto the MMP-9 null background exhibited a further increase in IOP. Interestingly, the MMP-9-deficient animals (without the TGFbeta transgene), which exhibited normal angle morphology, had increased IOP levels compared to their wild-type littermates. CONCLUSION: These results indicate that TGFbeta and MMP-9 likely act independently in regulating IOP. Additionally, MMP-9 plays an important role in maintaining IOP, and further investigation into the mechanisms of MMP-9 activity in the anterior angle may give clues to how extracellular matrix remodeling participates in ocular hypertension and glaucoma. |
