多西环素对碱烧伤大鼠角膜中波形蛋白和纤维连接蛋白表达的影响

Effects of doxycycline on the expression of vimentin and fibronectin in corneas of alkali burned rats

目的:探讨多西环素对碱烧伤大鼠角膜中波形蛋白(Vim)及纤维连接蛋白(Fn)表达的影响。方法:取健康SD大鼠右眼制备成角膜碱烧伤模型,随机分为对照组和多西环素组,每组27只。建模后多西环素组以1.0 g/L多西环素滴眼,而对照组以眼液溶媒点眼至临床观察期结束。分别于碱烧伤后的第3天、第7天和第14天进行角膜混浊程度的评分,角膜取材行病理切片苏木精-伊红(HE)染色并进行炎症细胞计数,分别用免疫荧光染色法(IF)和实时荧光定量PCR(qPCR)法检测角膜组织中Vim及Fn蛋白和m RNA的表达量。结果:多西环素组在碱烧伤后第7天和第14天角膜混浊程度较对照组轻(P<0.05),在各时间点的炎症细胞计数以及Vim及Fn mRNA的表达量和免疫荧光强度均较对照组降低(均P<0.05)。结论:多西环素可以减轻碱烧伤大鼠角膜混浊程度,其机制可能为减少细胞外基质蛋白Vim、Fn的沉积,抑制碱烧伤大鼠角膜纤维化。

Objective:To investigate the effects of doxycycline on the expression of vimentin(Vim)and fibronectin(Fn)in cornea of alkali burned rats.Methods:The corneal alkali burn model was prepared from the right eye of healthy SD rats and randomly divided into control group anddoxycycline group,with 27 rats in each group.After the model was established,the rats in doxycycline group received 1.0 g/L doxycycline eye-drops and those in the control groupreceived meustruum eye-drops until the end of clinical observation.Corneal opacity was scored on the 3 rd,7 th and 14 th days after alkali burn;corneal samples were taken for pathological section HE staining and inflammatory cell count;the mRNA and protein expression levels of Vim and Fn in corneal tissues were detectedby real-timefluorescence quantitative PCR(RT-PCR)and immunofluorescence staining,respectively.Results:Compared with the control group,the score of corneal opacity was decreased in the doxycycline group on the 7 th and 14 th day,the inflammatory cell count was reduced at any time point(P<0.05).The mRNA expression level and immunofluorescence intensity of Vim and Fn at each time point after alkali burn were both lower than those of the control group,and the differences were statistically significant(P<0.05).Conclusion:Doxycycline can reduce the degree of corneal opacification in alkali burned rats,the mechanism may be to reduce the deposition of extracellular matrix proteins Vim and Fn and inhibit corneal fibrosis in alkali burned rats.