Apical corneal barrier disruption in experimental murine dry eye is abrogated by methylprednisolone and doxycycline

Invest Ophthalmol Vis Sci. 2006 Jul;47(7):2847-56. doi: 10.1167/iovs.05-1281.


Purpose: To evaluate the mechanism of apical corneal epithelial barrier disruption in response to experimental ocular surface desiccation and the effects of two anti-inflammatory agents (methylprednisolone and doxycycline) on this process.

Methods: Experimental dry eye (EDE) was created in C57BL/6 mice, without or with topical therapy, 1% methylprednisolone, 0.025% doxycycline, or physiologic saline solution (PSS) four times per day. Corneal smoothness and Oregon green dextran (OGD) permeability were assessed. Desquamation of and cornified envelope protein (involucrin and small proline-rich protein [SPRR]-2) expression by the corneal epithelium was evaluated by laser scanning confocal microscopy. Levels of cornified envelope proteins mRNA were measured by real-time PCR.

Results: Corneal OGD permeability, surface irregularity, and the number of desquamating apical corneal epithelia significantly increased in EDE. Desiccating stress significantly increased expression of involucrin and SPRR-2 in the corneal epithelia. Treatment of EDE with methylprednisolone or doxycycline reduced corneal permeability to OGD, improved corneal smoothness, and decreased involucrin and SPRR-2 immunoreactivity compared with EDE+PSS.

Conclusions: Disruption of apical corneal epithelial barrier function in dry eye is accompanied by increased apical desquamation and increased expression of cornified envelope proteins. Topical treatment of EDE with the anti-inflammatory agents methylprednisolone or doxycycline preserves apical corneal barrier function.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anti-Inflammatory Agents / therapeutic use*
  • Cornified Envelope Proline-Rich Proteins
  • Disease Models, Animal*
  • Doxycycline / therapeutic use*
  • Dry Eye Syndromes / drug therapy*
  • Dry Eye Syndromes / metabolism
  • Dry Eye Syndromes / pathology
  • Epithelium, Corneal / drug effects*
  • Epithelium, Corneal / metabolism
  • Epithelium, Corneal / pathology
  • Fluorescent Antibody Technique, Indirect
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism
  • Methylprednisolone / therapeutic use*
  • Mice
  • Mice, Inbred C57BL
  • Microscopy, Confocal
  • Occludin
  • Organic Chemicals / metabolism
  • Permeability / drug effects
  • Protein Precursors / genetics
  • Protein Precursors / metabolism
  • RNA, Messenger / metabolism
  • Reverse Transcriptase Polymerase Chain Reaction
  • Transglutaminases / metabolism


  • Anti-Inflammatory Agents
  • Cornified Envelope Proline-Rich Proteins
  • Membrane Proteins
  • Occludin
  • Ocln protein, mouse
  • Oregon Green BAPTA-dextran
  • Organic Chemicals
  • Protein Precursors
  • RNA, Messenger
  • Sprr2a1 protein, mouse
  • involucrin
  • Transglutaminases
  • transglutaminase 1
  • Doxycycline
  • Methylprednisolone