Naltrexone, an opioid antagonist, facilitates reepithelialization of the cornea in diabetic rat.
Journal
  Diabetes.
Citation
  Diabetes. 51(10):3055-62
Publication date
  2002 Oct
Authors
  Zagon IS
Jenkins JB
Sassani JW
Wylie JD
Ruth TB
Fry JL
Lang CM
McLaughlin PJ
Investigators
  C. Max Lang
Patricia J. McLaughlin
Joseph W. Sassani
Ian S. Zagon
Grant agencies
  National Eye Institute
National Center for Research Resources
Grants
  NEI EY13086
NCRR RR07066
MeSH headings
  Corneal Ulcer
Diabetes Mellitus, Experimental
Epithelium, Corneal
Naltrexone
Narcotic Antagonists
MeSH qualifiers
  drug therapy
complications
cytology
pharmacology
Abstract
  Ulcers and erosions of the corneal epithelium, as well as delays in resurfacing of the cornea after wounding, are major causes of ocular morbidity and visual loss in diabetes. To study whether intervention by the opioid antagonist naltrexone (NTX; 30 mg/kg, twice daily) can restore reepithelialization in diabetic cornea, we induced diabetes in rats by intravenous injection of 65 mg/kg streptozotocin. After confirmation of diabetes, 5-mm-diameter epithelial defects that did not include the limbus were created by mechanical scraping of the cornea. At 4 and 8 weeks, corneal reepithelialization was markedly subnormal, with delays ranging from 11% to 17-fold in the diabetic animals compared with control counterparts. Rats that were diabetic for 8 weeks also had a significant decrease in the incidence of complete wound closure. At 4 and 8 weeks, diabetic animals that were receiving NTX had an acceleration in reepithelialization compared with diabetic animals that were receiving vehicle and even surpassed controls. DNA synthesis in the corneal epithelium of diabetic rats was decreased up to 90% of control levels, and NTX exposure of diabetic subjects elevated the labeling index by up to eightfold from diabetic animals that were receiving vehicle. Opioid growth factor and opioid growth factor receptor distribution were comparable in diabetic and control animals. These results indicate a delay in reepithelialization that is dependent on the duration of diabetes and that intervention of endogenous opioid-receptor interfacing with an opioid antagonist can facilitate the process of wound healing.
Medline ID
  22238610