The effect of ADP-ribosylation factor antagonist on alkali-burn induced corneal neovascularization / 中华实验眼科杂志

ABSTRACT

Background Corneal neovascularization (CNV) is one of the causes of corneal blindness.Studies showed that ADP-ribosylation factor (ARF) can regulate the growth of tumor cells,and inhibiting ARF will decrease angiogenesis.However,whether ARF antagonist plays an action on CNV is unclear.Objective The aim of this study was to explore the effect and mechanism of ARF inhibitor on alkali-burn induced CNV.Methods Sixty clean male BABL/c mice aged 7-8 weeks were divided into PBS group and ARF antagonist group according to randomized number table.CNV models were induced by NaOH burn method in all the mice.ARF at the concentration of 0.5 g/L(0.5 ml) was intraperitoneally injected 3 times per week for 1 week followed the induction of CNV in the ARF antagonist group,and 0.5 ml PBS was used in the PBS group.CNV was examined 2,4,7,14 days after injection by the slit lamp microscope and the CNV related area in the cornea was calculated.Betore modeling(0 day) and 4,7,14 days after modeling,real-time PCR and Western blot were used to analyze the expressions of ARF mRNA and protein in the corneas.Forteen days after modeling,the expression of the CD31 in the CNV was detected using immnofluorescence of corneal whole mount;the expression of vascular endothelial growth factor(VEGF) in the cornea was assayed by Western blot.Cellular wound scratch test was employed to evaluate the effects of ARF antagonist on proliferation and migration of human retinal vascular endothelial cells (RECs).All animal experiments were done in accordance with the ARVO Statement for the Use of Animals in Ophthalmic and Vision Research and Guideline for the Care and Use of Laboratory Animals on the the Soochow University Animal Care Committee.Results ARF mRNA and protein were expressed in the mice corneas in both the PBS group and the ARF antagonist group at various time points.The expression of ARF mRNA in mice corneas was enhanced with the lapse of the time (Ftime =65.17,P =0.00),but no significant difference was found among the groups (Fsroup =1.98,P=0.18).There was also significant difference in the expression of ARF protein in mice corneas at different time points in the ARF antagonist group (F =10.77,P =0.00).The related CNV area was 0.45±0.05 in the ARF antagonist group,and that in the PBS group was 0.72±0.11,with significant difference between them (t =-3.87,P ＜ 0.05).The green fluorescence area of C D31 expression in the cornea was smaller in the ARF antagonist group than that of the PBS group.Expression level of VEGF in the ARF antagonist group was 1.20±0.21,and that in the PBS group was 2.47±0.33,showing a significant difference (t =-5.62,P ＜ 0.05).As the increase of ARF antagonist concentration,the inhibiting rate of cell proliferation was reinforced among 10,100 and 1 000 μg/L ARF antagonist groups (F=8.47,P =0.02).Twenty-four hours after scratch test,the migrating distance of human RECs was (5.46±1.32) μm and (5.04±1.68) μm in the 100 μg/L and 1 000 μg/L ARF antagonist groups,respectively,which were shorter than (8.49± 1.18) μm of the PBS group (t=-2.94,-2.91,both at P＜0.05).Conclusions ARF inhibitor can reduce CNV by down-regulating the expression of VEGF in alkaline burn cornea and inhibiting the proliferation and migration of vascular endothelial cells.