Dexamethasone induced ultrastructural changes in cultured human trabecular meshwork cells

Area of Science:

• Ophthalmology
• Cell Biology
• Pharmacology

Background:

• Glucocorticoid-induced ocular hypertension is a known clinical condition.
• Trabecular meshwork (TM) cell dysfunction is a potential underlying cause.
• Understanding cellular responses to glucocorticoids is crucial for managing this condition.

Purpose of the Study:

• To investigate the ultrastructural effects of dexamethasone (DEX) on human trabecular meshwork (TM) cells.
• To determine if DEX treatment alters TM cell morphology and intracellular organization.

Main Methods:

• Human TM cell lines were treated with 0.1 microM dexamethasone (DEX) for 14 days.
• Cells were analyzed using light microscopy, epifluorescent microscopy, and transmission electron microscopy (TEM).
• Computer-assisted morphometrics quantified changes in cell and nuclear size.

Main Results:

• Dexamethasone treatment significantly increased human TM cell and nuclear size.
• Actin cytoskeleton showed altered, geodesic dome-like networks in DEX-treated cells.
• TEM revealed stacked endoplasmic reticulum, Golgi proliferation, pleomorphic nuclei, and increased extracellular matrix in DEX-treated cells.

Conclusions:

• Dexamethasone induces significant ultrastructural alterations in human TM cells.
• These observed cellular changes provide insights into the mechanisms of glucocorticoid-induced ocular hypertension.
• The study highlights potential cellular pathways involved in steroid-induced glaucoma.