Inhibitory Effect And Mechanism Of Small Molecule Compounds Targeting Nanoparticle Suspension Of Mixed Liquid Bcl-2on Rat’s Corneal Neovascularization Induced By Alkali Cauterization

Purpose：Small molecule compounds targeting nanoparticle suspension of mixedliquid Bcl-2(Z24-NS) based on the use to eyes without its side effect. To investigatethe inhibitory proliferation effect of Z24-NS on corneal neovascularization after alkaliburn in rat，and to explore its possible mechanism. Provide theoretical foundation forclinical application in the future.Methods：1．Eight SD rats were randomly divided into two groups:the Z24group and salinesolution group，four rats (4eyes) were in each group. The2％Z24-NS eye drop wasgiven to left eyes of Z24group’s rats，and topical instillation of0.9%saline solutionwas given to left eyes of control group’s rats. The toxicity effects and side effects of2％Z24-NS were observed by praxiology，slit-lamp biomicroscope，pathologicalspecimens were made to observe the differences under light microscopes after14days.2．The alkali burn induced CNV models were established by placing a3×3mmfilter paper saturated with1mol/L NaOH at the central corneas of the left eyes of36rats for40seconds，which were distributed randomly into3groups: treatment groupof Z24-NS eye drop，positive control group of Dexamethasone sodium phosphate eyedrop to left eyes and blank group，twelve rats (12eyes) were in each group. The2％Z24-NS eye drop was given to treatment group，0.1%Dexamethasone sodiumphosphate eye drop was given to positive control group for four times daily，blankgroup without any treatment，experimental period is14days. The growth of cornealneovascularization，the level of corneal opacity and inflammatory were observedqualitively and quantitively by slit-lamp biomicroscope on3d、7d、14d after alkalicauterization，the CNV area was calculated in different groups.3．Analysis of the number of inflammatory cells，microvessel density of each group corneal by pathological specimens observation and computer image，theexpression of the protein and mRNA of VEGF、Flk-1and Bcl-2in the corneal tissuewere detected by immunohistochemistry、RT-PCR and Western Blot on14d afteralkali cauterization，according to the results of the second step.Results:1．Throwing head，scratching eye，photophobia were not observed and cornealclouding，edema，epithelial defect were not found after dropped with2％Z24-NSeye drop on normal rat’s cornea. The corneal histological structure was normalwithout the inflammatory cell infiltrate in all corneas.2. On the3d、7d、14d after cornea alkali injury，the corneal neovascularizationarea，the inflammatory index and the level of corneal opacity of Z24group anddexamethasone group were all significantly less than those of blank group(P<0.01orP<0.05). No significant difference in corneal NV area，the inflammatory index andthe level of corneal opacity were found between dexamethasone group and Z24group(P>0.05).3．On the14d after cornea alkali injury，the number of inflammatory cells，microvessel density and the expression of the protein and mRNA of VEGF、Flk-1andBcl-2in the corneal tissue of Z24group and dexamethasone group were allsignificantly less than those of blank group(P<0.01or P<0.05).No significantdifference were found between dexamethasone group and Z24group(P>0.05). Bothgroups VEGF and Flk-1expression was positively correlated with the number ofMVD(r1=0.9997，P1=0.015；r2=0.9999，P2=0.011).Conclusion：1．The rat cornea structure didn’t change after short-term ocular application of2％Z24-NS eye drops，which is safe on eye application.2．Topical application of2％Z24-NS eye drop has a significant antiangiogeniceffect against the rat corneal neovascularization induced by alkali cauterization andthe level of corneal opacity can be reduced correspondingly，which is not significantlydifferent compared with0.1%Dexamethasone eye drop. 3．2％Z24-NS eye drop had the effect of anti-inflammatory. Its can downregulatethe expression of VEGF and its receptor Flk-1、Bcl-2in cornea of rat CNV model，sothat2％Z24-NS eye drop inhibit the growth of CNV effectively.