Effect of metalloproteinase inhibitor on corneal cytokine expression after alkali injury.
OBJECTIVE
Interleukin (IL)-1alpha and IL-6 levels in the cornea are greatly elevated during the early stages after an alkali burn in mice. The authors investigated the effect of synthetic inhibitor of matrix metalloproteinase (SIMP) on the expression of inflammatory cytokines in alkali-burned murine corneas and evaluated the clinical appearance of the eyes.


METHODS
After 0.5N NaOH-alkali burns to 400 corneas of ICR mice, 200 received 400 microg/ml of SIMP topically 4 times a day while 200 corneas were similarly treated with vehicle only. At days 4, 7 and 14 after injury, each cornea was assigned a clinical score for corneal opacity, corneal epithelial defect, hyphema and cataract. Extracts of injured corneas in each group were then assayed for cytokine production using ELISA systems for IL-1alpha, IL-1beta, IL-6 and tumor necrosis factor-alpha (TNF-alpha).


RESULTS
The levels of IL-1alpha, IL-1beta and IL-6 were significantly lower in the SIMP-treated group than in the vehicle-treated group 7 days after the burn. However, levels of these cytokines were similar in the SIMP and non-SIMP groups at days 4 and 14. Levels of TNF-alpha did not differ between both groups at any postinjury time. In the SIMP-treated corneas, there was less opacification and hyphema formation and epithelial regeneration was faster.


CONCLUSIONS
Topical application of SIMP in alkali-burned murine corneas reduced the expression of IL-1alpha, IL-1beta, and IL-6 and lessened the severity of the injury.
Sotozono
C
C
Department of Ophthalmology, Kyoto Prefectural University of Medicine, Japan. csotozon@eyeeye.ophth.kpu-m.ac.jp
He
J
J
Tei
M
M
Honma
Y
Y
Kinoshita
S
S
D000818:Animals; D002057:Burns, Chemical / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D003315:Cornea / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D016207:Cytokines / Q000378:metabolism*; D004151:Dipeptides / Q000494:pharmacology*; D005126:Eye Burns / Q000139:chemically induced* / Q000378:metabolism / Q000473:pathology; D005260:Female; D008666:Metalloendopeptidases / Q000037:antagonists & inhibitors*; D051379:Mice; D008813:Mice, Inbred ICR; D011480:Protease Inhibitors / Q000494:pharmacology*; D012972:Sodium Hydroxide
D016207:Cytokines; D004151:Dipeptides; C078131:N-(2(R)-2-(hydroxamidocarbonylmethyl)-4-methylpentanoyl)-L-tryptophan methylamide; D011480:Protease Inhibitors; D012972:Sodium Hydroxide; D008666:Metalloendopeptidases