Mechanical corneal epithelium scraping and ethanol treatment up-regulate cytokine gene expression differently in rabbit cornea
Journal
Journal of Refractive Surgery
Journal Volume
24
Journal Issue
2
Date Issued
2008-01-01
Author(s)
Abstract
PURPOSE: To explore inflammation and wound healing in the rabbit eye following topical ethanol treatment or mechanical debridement. METHODS: Seventy-six pigmented rabbit corneas were divided into four groups: mechanical group (n=33), which received mechanical epithelial debridement; ethanol-30 (n=18) and ethanol-60 groups (n=18), which were treated with 20% ethanol for 30 and 60 seconds, respectively; and control group (n=7), which remained untreated. Corneal epithelial and stromal keratocyte changes were examined with hematoxylin-eosin and terminal deoxynucleotidyltransferase-mediated dUPT nick end labeling (TUNEL) staining at 3 hours (day 0) and days 1, 2, 3, 5, and 7. Interleukin (IL)-1α, IL-8, monocyte chemotactic protein (MCP-1), and transforming growth factor (TGF)-β1 expression were examined using real-time polymerase chain reaction. RESULTS: Stromal keratocyte cell death was higher in the mechanical group on day 0 (P=.002) and in the ethanol-60 group on days 3, 5, and 7 (P<.05). Keratocyte cell death was more pronounced in the ethanol-60 group than in the ethanol-30 group. In the mechanical group, IL-1α, IL-8, and MCP-1 expression was up-regulated starting on day 0 (P<.05) and returned to baseline on day 5 to 7. TGF-β1 expression was up-regulated in the mechanical group throughout the experiment (P<.05). In the ethanol-30 and ethanol-60 groups, IL-1α expression was up-regulated on day 0, IL-8 expression was slightly up-regulated on day 0, and MCP-1 and TGF-β1 expression were not up-regulated. CONCLUSIONS: Mechanical epithelial removal initially induces more keratocyte cell death, but deep stromal keratocyte death persists longer with ethanol treatment. In this rabbit model, mechanical epithelial removal up-regulated inflammatory cytokines and TGF-β1 gene expression more than ethanol treatment.
SDGs
Type
journal article