Expression of BFGF and IL-1 Alpha in Tears of Galactosemic Rats: Implications for Wound Healing and Neovascularization

Abstract

Purpose: : To compare tear levels of bFGF and IL-1a in control and galactosemic rats pre- and post-corneal epithelial wounding. We hypothesize that tear levels of bFGF and IL-1a assist corneal epithelial regeneration, regulate angiogenesis, and modulate inflammatory responses. Therefore, these tear components may influence the occurrence of keratopathy, delayed wound healing, and neovascularization in the galactosemic rat cornea.

Methods: : Male SD rats were randomized into two groups (n=6) and fed ad libidum Purina 5001 with either 50% starch (control) or 50% D-galactose for two months. Tears were collected preceding and two weeks after corneal epithelial wounding and placed in Tris (pH 7.4) with protease inhibitors. The corneal wounds were made with sterile 3 mm trephine punch and removal of epithelium with a scalpel blade under isoflurane anesthesia. Microbead antibody immunoassay was used for assay of bFGF and IL-1 a.

Results: : Mean (±SE) basal tear levels of bFGF and IL-1 in control rats were significantly higher than in the age-matched two-month galactosemic rats. Two weeks post corneal wounding bFGF and IL-1a in tears of the control animals were unchanged from pre-wounding concentrations. In contrast, bFGF and IL-1a levels were elevated several fold in the galactosemic rat.

Conclusions: : This is the first quantitation of bFGF and IL-1a in tears of galactosemic rats. Suppressed basal tear expression of bFGF and IL-1a may contribute to the keratopathy and delayed wound healing seen in this animal model. Polyol effects on bFGF/IL-1a expression remain to be determined. The elevation of bFGF and IL-1a in tears of galactosemic rats post corneal stress could render the cornea susceptible to neovascularization and a pro-inflammatory state. The findings from this study have clinical relevance in ocular surface conditions such as diabetic keratopathy, dry eye, and following keratectomy.

Keywords: cornea: epithelium • wound healing