Dexamethasone Modulates the Dynamics of Wnt Signaling in Human Trabecular Meshwork Cells

Area of Science:

• Ocular biology
• Glaucoma research
• Cell signaling

Background:

• Trabecular meshwork (TM) integrity is vital for maintaining intraocular pressure (IOP).
• Glucocorticoids like dexamethasone (DEX) can increase IOP and cause steroid-induced glaucoma.
• The precise mechanisms of steroid-induced glaucoma are not fully understood, but DEX affects TM cell signaling.

Purpose of the Study:

• To investigate the impact of DEX on the Wnt signaling pathway in TM cells.
• To explore the role of Wnt signaling in the glaucomatous phenotype.
• To analyze the relationship between Wnt markers and DEX-induced myocilin expression.

Main Methods:

• Primary TM cells were treated with DEX for 10 days.
• mRNA expression of Wnt signaling markers (AXIN2, sFRP1) and MYOC was analyzed.
• MYOC protein levels were also assessed.

Main Results:

• A sequential pattern of peak expression was observed for AXIN2, sFRP1, and MYOC.
• DEX treatment altered Wnt signaling pathway markers in TM cells.
• MYOC mRNA and protein levels were induced by DEX.

Conclusions:

• DEX influences Wnt signaling in TM cells, contributing to potential glaucomatous changes.
• Upregulation of sFRP1 may represent a negative feedback response to suppress aberrant Wnt signaling in stressed TM cells.
• Understanding these pathways could offer insights into managing steroid-induced glaucoma.