Abstract
Purpose :
Topical application of the fibronectin-derived peptide PHSRN has previously been shown to facilitate corneal epithelial wound healing in healthy animals as well as in patients with persistent epithelial defects. We have now examined the effect of PHSRN eyedrops on the healing of corneal epithelial wounds in rats with streptozotocin-induced diabetes.
Methods :
Four-week-old Wistar rats were injected intraperitoneally with streptozotocin (70 mg/kg, n = 12) or vehicle (n = 8). Four weeks after confirmation of the presence or absence of glycosuria, a 3-mm-diameter portion of the corneal epithelium of the right eye was excised. Eyedrops containing PHSRN (200 µM) or phosphate-buffered saline (PBS) vehicle were administered to the injured eye of the diabetic or nondiabetic animals every 6 h. The epithelial defect as revealed by fluorescein staining was also photographed every 6 h. For evaluation of the effect of PHSRN at different doses, eyedrops containing 0, 2, 20, or 200 µM peptide were applied to the corneal defect of diabetic rats every 6 h and the defect was photographed at 0 and 18 h. The area of epithelial defects was determined from photographs with the use of Image J software.
Results :
The area of the epithelial defect did not differ significantly among the four experimental groups (diabetic or control rats treated with PHSRN or vehicle) at 12 h after wounding. At 18 h, however, the area of the defect in diabetic rats treated with PHSRN (0.50 ± 0.34 mm2) was significantly (P < 0.05) smaller than that in diabetic rats treated with PBS (1.06 ± 0.42 mm2) and was similar to that in nondiabetic rats treated with PBS (0.60 ± 0.23 mm2). The decrease in size of the epithelial defect in diabetic rats treated with PHSRN was dependent on the dose of the peptide.
Conclusions :
The administration of PHSRN eyedrops significantly facilitated the healing of corneal epithelial wounds in diabetic rats. Our data therefore suggest that PHSRN eyedrops warrant investigation as a promising treatment option for patients with diabetic keratopathy.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.