重组胸腺素β4调节兔角膜碱烧伤后MMP-2和TIMP-2的表达  

Expression of MMP-2 and TIMP-2 regulated by recombinant thymosine β4 after corneal alkali burn in rabbits

作　　者：龙安华[1] 李明[1] 王晓坤[1] 司文[1] 李玄德[1] 聂李亚[2] 马素永[2] 车永哲[1] 许松山[2] 

机构地区：[1]南开大学医学院生物活性材料教育部重点实验室,天津市300071 [2]北京诺思兰德生物技术有限公司,北京市100085

出　　处：《眼科新进展》2010年第8期723-726,共4页Recent Advances in Ophthalmology

基　　金：南开大学第六届本科生创新科研"百项工程"立项项目基金资助(编号:BX6-248)~~

摘　　要：目的探讨重组胸腺素β4(thymosinβ4,Tβ4)调节基质金属蛋白酶2(matrix metalloproteinase-2,MMP-2)、组织金属蛋白酶抑制剂-2(tissue inhibitor of matrix metalloproteinase-2,TIMP-2)、血管内皮生长因子(vascular endothelial growth factor,VEGF)表达及促进兔角膜碱烧伤愈合的作用机制。方法用40g.L-1NaOH浸透的6mm直径圆滤纸片贴于兔角膜中央30s,建立兔角膜碱烧伤模型。60只健康成年新西兰白兔随机分为实验组和对照组,实验组每天2次分别给予低剂量(0.002g.L-1)、中剂量(0.02g.L-1)、高剂量(0.2g.L-1)Tβ4,对照组每天2次分别给予PBS(阴性对照组)和rh-EGF(金因舒滴眼液,阳性对照组)滴眼。分别于角膜碱烧伤后第3天、第5天、第7天、第9天、第11天观察角膜烧伤面积的变化,并统计角膜愈合率;分别于角膜碱烧伤后第1天、第3天、第7天、第14天免疫细胞化学染色检测MMP-2、TIMP-2和VEGF表达。结果在角膜碱烧伤后第11天,实验组高剂量Tβ4组角膜愈合率最高达33.76%,阴性对照组为22.69%,阳性对照组为21.38%,实验组高于阳性对照组(P<0.01或P<0.05),其中中剂量Tβ4组角膜碱烧伤后第3天、第5天、第7天、第9天角膜愈合率高于其他剂量组,但差异均无统计学意义(均为P>0.05)。免疫细胞化学显示早期(第1天和第3天)各组MMP-2表达差异无统计学意义(P>0.05),后期(第7天和第14天)实验组较阴性对照组明显升高,差异均有统计学意义(P<0.05或P<0.01)。TIMP-2在各时期组间比较,差异均无统计学意义(均为P>0.05);在角膜碱烧伤后第14天时,rh-EGF阳性对照组平均积分光密度染色最深,实验组染色明显弱于rh-EGF阳性对照组。结论重组Tβ4可能是通过调节MMP-2和TIMP-2的表达,影响二者的平衡,协同调节多种因子促进新生组织重塑,促进角膜碱烧伤修复。Objective To investigate the mechanisms of recombinant thymosin β4 （Tβ4） promoting corneal wound healing after alkali burn by regulating the expression of matrix metalloproteinase-2 （ MMP-2 ）, tissue inhibitor of metalloproteinase-2 （TIMP-2） and vascular endothelial growth factor（VEGF）. Methods Rabbit corneal alkali burn models were built by sticking round filter paper with 6 nun diameter soaked at 40 g · L - 1 NaOH to central part of rabbit cornea for 30 seconds. A total of 60 healthy New-Zealand rabbits were randomly divided into experimental group and control group. Rabbits in experimental group were given Tβ4 at low dose （0. 002 g · L-1 ）, medium dose （0.02 g· L- 1 ） and high dose （ 0.2 g · L - 1 ）, twice a day. Rabbits in control group were given PBS （ negative control group） and rh-EGF （ Gene soft eyedrops, positive control group）, twice a day. Changes of corneal alkali burn areas were observed on the 3rd day,5th day,7th day,9th day and llth day after alkali burn,respectively,and corneal wound healing rate was counted. Immunohistochemical staining was used to detect the expression of MMP- 2 ,TIMP-2 and VEGF on the 1st day,3rd day,7th day and 14th day after alkali burn. Results On the 11 th day after corneal alkali burn,the corneal wound healing rates were 33.76% in experimental group,22.69% in negative control group and 21.38% in positive control group. The wound healing rates in experimental group were higher than those in control groups （P 〈 0, 01 or P 〈 0. 05 ）. Corneal wound healing rates in Tβ 4 group at medium dose were higher than those in other groups at different doses on the 3rd,5th ,7th and 9th day after corneal alkali burn, respectively, but no significant difference was found （ all P 〉 0. 05 ）. Immunohistochemical method showed no statistical difference was found in MMP-2 expression at the early stage（ the 1st day and the 3rd day） （P 〉 0.05 ）. MMP-2 expression in experimental group was higher than that in negative control group

关 键 词：胸腺素Β4 角膜 碱烧伤 基质金属蛋白酶-2 创伤愈合 

分 类 号：R772.21[医药卫生—眼科]