Effect of Tempol, a Membrane-Permeable Free Radical Scavenger, on In Vitro Model of Eye Inflammation on Rabbit Corneal Cells

J Ocul Pharmacol Ther. 2019 Dec;35(10):571-577. doi: 10.1089/jop.2019.0016.

Abstract

Purpose: Inflammatory corneal diseases such as bacterial keratitis provoke severe injury to the visual functions and physical structure, leading to opaqueness, wounding, damage to the cornea, and even long-lasting vision loss. Usually antioxidant substances have been of great attention as candidate therapies in the management of keratitis in both humans and animals. Based on the findings, the aim of our research was to examine the effects of Tempol (4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl), a membrane-permeable free radical scavenger with exclusive antioxidant properties, on in vitro model of eye inflammation of rabbit corneal cells stimulated with lipopolysaccharide (LPS) (Seruminstitute Rabbit Cornea). Methods: The cells were pretreated with Tempol and incubated with LPS for 24 h. LPS stimulation triggered increased cellular mortality, oxidative stress, cytokine levels expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6, and also enhanced prostaglandin E2 (PGE2) levels and cyclooxygenase-2 (COX-2) expression. Results: Pretreatment with Tempol (3 mM) significantly increased cell viability and antioxidant activity as well as decreased reactive oxygen species production, cytokines, PGE2 levels, and COX-2 expression. Conclusions: Taken together, Tempol could be a new therapeutic strategy for management of ocular inflammatory disorders for clinical and veterinary use.

Keywords: Tempol; inflammation; keratitis; oxidative stress; rabbit corneal.

MeSH terms

  • Animals
  • Cell Survival / drug effects
  • Cells, Cultured
  • Cornea / drug effects*
  • Cornea / metabolism
  • Cornea / pathology
  • Cyclic N-Oxides / administration & dosage
  • Cyclic N-Oxides / pharmacology*
  • Disease Models, Animal*
  • Free Radical Scavengers / administration & dosage
  • Free Radical Scavengers / pharmacology*
  • Inflammation / drug therapy*
  • Inflammation / metabolism
  • Inflammation / pathology
  • Keratitis / drug therapy*
  • Keratitis / metabolism
  • Keratitis / pathology
  • Lipopolysaccharides / antagonists & inhibitors
  • Lipopolysaccharides / pharmacology
  • Rabbits
  • Reactive Oxygen Species / analysis
  • Reactive Oxygen Species / metabolism
  • Spin Labels

Substances

  • Cyclic N-Oxides
  • Free Radical Scavengers
  • Lipopolysaccharides
  • Reactive Oxygen Species
  • Spin Labels
  • tempol