The influence of ursolic acid on VEGF, COX-2 and MMP-2 expressed in the mouse retinal ischemic model

Abstract

Objective To investigate the influence of ursolic acid on vascular endothelial growth factor （ VEGF） , cycloxygen-ase-2 （COX-2）, and matrix metalloproteinases-2 （MMP-2） expressed in the mouse retinal ischemic model , and to explore the mecha-nisms of anti-angiogenesis.Methods Sixty 7-day clean-class C57BL/6J mice were divided randomly into 6 groups [ n =10 mice （20 eyes） per group]：blank control, model control （PBS）, positive control （triamcinolone）, and ursolic acid （UA） intervention （low-dose, medium-dose, and high-dose）.Mice in the blank control group were raised in air , and mice in other groups in（75%±2%）O2 high-oxygen environment for 5 consecutive days .Mice in the model control group and breastfeeding mice were put back in air environ-ment （21%O2 ） on the 12th day after the new-born mice to induce the generation of retinal neovascularization .When models were suc-cessful, the drug treatments were applied immediately to the corresponding groups , with injection of 3μl of sterile PBS in model control group, 3 μl of 1.5, 3.00 and 6.0 μg UA in UA intervention group, and 3 μl of triamcinolone （1 ml∶40 mg） in positive control group, respectively.All mice were killed after overdose anesthesia on the 17th day.Their eyeballs were made into samples and retinal tissue pathological sections with H-E dying method.The positive expressions of VEGF , COX-2, and MMP-2 were detected with immu-nohistochemical method .The fresh retinal tissue homogenate was prepared to detect the protein expressions of VEGF , COX-2, and MMP-2 in retinal tissue with western blot method ,and mRNA expressions of VEGF , COX-2, and MMP-2 were detected with real-time fluorescent quantitative polymerase chain reaction （ RT-PCR） .Results According to protein and mRNA expressions of VEGF , COX-2,and MMP-2 in retinal tissue among six groups , protein expressions of VEGF , COX-2, and MMP-2 in model group were significantly＆amp;nbsp;higher than those in blank group （ P 0.05 ） .Each protein expression in the high UA intervention group was significantly lower than that in the low UA intervention group（ P <0.05）.Conclusions UA inhibited expressions of VEGF, COX-2, and MMP-2 in retinal ischemia model .UA also played an inhibitory role in the formation of neovascularization , and this role was positively correlated with UA dose . Key words: URSOLIC ACID/pharmacology; Ischemia; Retinal diseases; Vascular endothelial growth factors/metabolism; Matrix metalloproteinase 2/metabolism; Prostaglandin-endoperoxide synthases/biosynthesis