Abstract
PURPOSE. Glucocorticoid (GC)-induced ocular hypertension (GC-OHT) is a serious side effect of prolonged GC therapy that can lead to glaucoma and permanent vision loss. GCs cause a plethora of changes in the trabecular meshwork (TM), an ocular tissue that regulates intraocular pressure (IOP). GCs act through the glucocorticoid receptor (GR), and the GR regulates transcription both through transactivation and transrepression. Many of the antiinflammatory properties of GCs are mediated by GR transrepression, while GR transactivation largely accounts for GC metabolic effects and side effects of GC therapy. There is no evidence showing which of the two mechanisms plays a role in GC-OHT. METHODS. GRdim transgenic mice (which have active transrepression and impaired transactivation) and wild-type (WT) C57BL/6J mice received weekly periocular dexamethasone acetate (DEX-Ac) injections. IOP, outflow facilities, and biochemical changes to the TM were determined. RESULTS. GRdim mice did not develop GC-OHT after continued DEX treatment, while WT mice had significantly increased IOP and decreased outflow facilities. Both TM tissue in eyes of DEX-treated GRdim mice and cultured TM cells isolated from GRdim mice had reduced or no change in the expression of fibronectin, myocilin, collagen type I, and α-smooth muscle actin (α-SMA). GRdim mouse TM (MTM) cells also had a significant reduction in DEX-induced cytoskeletal changes, which was clearly seen in WT MTM cells. CONCLUSIONS. We provide the first evidence for the role of GR transactivation in regulating GCmediated gene expression in the TM and in the development of GC-OHT. This discovery suggests a novel therapeutic approach for treating ocular inflammation without causing GCOHT and glaucoma.
Original language | English |
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Pages (from-to) | 1967-1978 |
Number of pages | 12 |
Journal | Investigative Ophthalmology and Visual Science |
Volume | 60 |
Issue number | 6 |
DOIs | |
State | Published - May 2019 |
Keywords
- Glucocorticoid receptor
- Intraocular pressure
- Mouse
- Trabecular meshwork
- Transactivation