Inhibitory Effects Of Thymoquinone On Rabbits Corneal Neovascularization

Objective: To investigate the inhibitory effect of thymoquinone (TQ) on cornealneovascularization (CNV) in rabbits and determine the optimal effectiveconcentration.Methods: A total of45healthy New Zealand white rabbits were selected. Fiverabbits received no treatment and were used as the normal control group (group A).The other40rabbits were used to establish the alkali burn model and were randomlydivided into4groups (groups B, C, D, and E; n=10each). Groups B, C, and Dreceived0.1,0.4, and0.8%TQ eye drops, respectively, and group E received0.8%TWEEN20eye drops. The development of CNV was observed and photographedunder a slit lamp after1,7,14,21, and28d. The expression and relative levels ofVEGF in the corneas after28d were detected using immunohistochemistry andreal-time quantitative polymerase chain reaction (RT-PCR). The results werestatistically analyzed.Results:1. The corneal structure in group A was normal,and without new bloodvessels form;The rest area of CNV at all time points between the four groups,difference was statistically significant ((Fgroup=214.572, P <0.01;Ftime=5.228, P <5.228), B, C, D group length and area of CNV were smaller than that of group E, themean of CNV area is group D> B> C.2. The immunohistochemistry results showedthat the differences in the corneal VEGF expression levels among these groups werestatistically significant (F=16.23, P0.01). Pairwise comparisons between group Eand the other3groups found P values smaller than0.01for all comparisons,indicating that the differences were statistically significant. Comparisons between groups B and C and between groups B and D both showed that the differences werenot statistically significant (P>0.05). A comparison between groups C and D hadP0.05; the difference was statistically significant. These results indicate that theVEGF-positive expression was the lowest in group C.3. The RT-PCR results showedthat the relative VEGF mRNA levels in the corneal tissues between the experimentalgroups and the control group were significantly different (F=37.05, P0.01). Controlgroup relative expression of corneal VEGFmRNA higher than that of theexperimental group, Tip a concentration of0.4%TQ is the lowest.Conclusion: By observing the CNVs produced after alkali burn injuries in rabbitsand the resulting VEGF expression in corneal tissues,TQ can effectively inhibit CNVin rabbits after an alkali burn injury, and a concentration of0.4%TQ was the mosteffective.