Effect of ursolic acid on retinal vascular form in oxygen-induced mouse retinopathy / 中华实用儿科临床杂志

ABSTRACT

Objective To investigate the effect of ursolic acid (UA) on retinal vascular form in oxygen-induced mouse retinopathy.Methods The 60 clean 7-day C57BL/6J mice were divided into 6 groups randomlyblank control group,model control group (PBS),positive control group (triamcinolone),UA intervention group (low dose,meta dose,high dose),with 10 mice in each group(right eye as experimental subject,10 eyes each group).The blank control group mice were raised in air,with other groups of mice in (750 ± 20) mL/L O2 high-oxygen environment for 5 consecutive days.The model control group mice and breastfeeding mice were put back in air enviroment(210 mL/L O2) on the 12th day after birth to induce the generation of retinal neovascufarization.The drug treatment was applied to the corresponding groups immediately when models were successful3 μL sterile PBS was injected in model control group,3 μL 1.5,3.0 and 6.0 μg UA in UA intervention group,3 μL triamcinolone(1 mL ∶ 40 mg) in positive control group.All mice were killed after overdose of anesthesia on the 17th day,and their eyeballs were made into retinal tissue sections,HE dying,counting the neovasculanzation endothelial nuclei number which broke the retinal internal limiting membrane.The morphologic changes of retinal vessels were estimated by observing the vascular pattern with the technology of stretched preparation of retina.Results From the observation of tissue pathology slice in blank control group,the structure of internal limiting membrane was even,and the vascular endothelial cells lined up evenly,while some vascular endothelial cells broke the internal limiting membrane occasionally.In model control group,a lot of vascular endothelial cells broke the internal limiting membrane and new vessel lumen was formed.The result of low UA intervention group was basically similar to that of model control group.The result of high-dose UA intervention group was close to that of positive control group,though some vascular endothelial cells broke the internal limiting membrane,and internal limiting membrane structure was even,and new vessel lumen was not formed.The endothelial nuclei number of newly-generated internal limiting membrane vessel in model control group was obviously higher than that of blank control group,while the high-dose UA intervention group was obviously lower than that of model control group,and the high-dose UA intervention group was lower than that of the low-dose UA intervention group obviously,and all the differences were statistically significant(P ＜ 0.05).Retinal flatmounts showed that in the blank control group retinal vascular appeared with uniformly radiated distribution from optic disc in all directions,with bigger pipe diameter,proper branch and clear peripheral retinal vascular structure.However,lots of retinal neovascularization was seen in model control group,with slender retinal diameter,line rigidity,structure disorder,and uneven distribution,and there was large non-perfused areas in the centeral area.Through comparison with different doses UA intervention group,retinal vascular distribution and pattern in the high-dose UA intervention group were close to the positive group.The distribution of retinal neovascularization was much better than the model control group and the low-dose UA intervention group,with no obvious non-perfused areas.Conclusions UA can inhibit the formation of neovascularization in oxygen-induced mice retinal ischemia model.It has a positively correlated relationship with UA dose.