Effect of silver nitrate solution on corneal epithelial barrier function in rabbits

Area of Science:

• Ophthalmology
• Corneal Physiology
• Drug Formulation

Background:

• Preservatives in ophthalmic solutions can cause corneal epithelial damage.
• Diquafosol sodium, a 2022 dry eye treatment, utilizes silver nitrate as a preservative.

Purpose of the Study:

• To investigate the impact of diquafosol sodium ophthalmic solution and silver nitrate on corneal epithelial barrier function.
• To evaluate the effects of different concentrations of silver nitrate on corneal resistance.

Main Methods:

• Rabbit eyes were treated with various formulations of diquafosol sodium (with/without silver nitrate) and silver nitrate solutions.
• Corneal resistance (CR) was measured, and corneal epithelial damage was assessed using fluorescein staining.
• Immunohistochemical staining was performed to visualize zonula occludens-1 (ZO-1) protein expression.

Main Results:

• Diquafosol LX with silver nitrate showed significantly increased corneal resistance (CR) compared to diquafosol without silver nitrate.
• The CR levels in the Diquas LX with silver nitrate group were comparable to the 0.1% silver nitrate group.
• Zonula occludens-1 protein exhibited a continuous linear pattern at epithelial cell boundaries in all diquafosol groups.

Conclusions:

• Diquas LX eye drops containing silver nitrate enhance corneal barrier function compared to those without silver nitrate.
• Silver nitrate may play a role in improving corneal barrier function in diquafosol sodium formulations.
• These findings suggest a potential benefit of silver nitrate as a preservative in dry eye treatments.