周期性机械拉伸对兔角膜成纤维细胞MMP-2/TIMP-2及TGF-β1表达的影响

摘要

研究了周期性机械拉伸对角膜成纤维细胞外基质中金属蛋白酶-2 (Matrix metalloproteinase-2,MMP-2)、组织金属蛋白酶抑制剂-2(Tissue inhibitors of metalloproteinase-2,TIMP-2)及转化生长因子-β1 (Transforming growth factorβ1,TGF-β1)表达的影响.对正常兔角膜成纤维细胞进行幅度分别为5％、10％及15％的周期性机械拉伸,并分别于拉伸后6h、24 h取细胞培养液,采用ELISA方法检测MMP-2、TIMP-2及TGF-β1的含量.当拉伸幅度为5％时,6h、24 h后,MMP-2、TIMP-2及TGF-β1的含量与静态对照组相比均无统计学差异；当拉伸幅度为10％时,6h后MMP-2、TIMP-2及TGF-β1的含量与静态对照组相比无统计学差异,24 h后MMP-2的含量显著升高(p＜0.05)；当拉伸幅度为15％时,6h后MMP-2、TIMP-2及TGF-β1的含量与静态对照组相比仍无统计学差异,拉伸24 h后MMP-2、TGF-β1含量显著升高,TIMP-2含量显著降低(p＜0.05).结果表明,在体外以一定的幅度周期性拉伸角膜成纤维细胞一定时间后,细胞分泌的MMP-2、TIMP-2及TGF-β1发生显著改变,三者相互作用,共同调节角膜成纤维细胞的生物学行为.%To investigate and determine the effect of cyclic mechanical stretch on the expression of Matrix metalloproteinase-2 (MMP-2), Tissue inhibitors of metalloproteinase-2 (TIMP-2) and Transforming growth factor (31 (TGF-βl)in extracellular matrix remodeled by corneal fibroblasts, corneal fibroblasts were isolated from normal rabbits and subjected to a cyclic stretch regimen of 5%, 10% and 15% elongation. The concentration of MMP-2, TIMP-2 and TGF-pi was assayed on aliquots of culture medium by ELISA method after stretched for 6 h and 24 h separately. Our results show that: When the amplitude of stretch was 5%, there was no significant difference in MMP-2, TIMP-2 and TGF-βl among groups at 6 h or 24 h;When the amplitude of stretch was 10% , there was also no significant difference in MMP-2, TIMP-2 and TGF-pi among groups at 6 h,but level of MMP-2 was significantly(P<0. 05) elevated at 24 h; When the amplitude of stretch was 15% , there was also no significant difference in MMP-2, TIMP-2 and TGF-βl among groups at 6 h,but level of MMP-2, TGF-β1 was significantly (P<0. 05) elevated and TIMP-2 decreased at 24 h. It indicates that MMP-2, TIMP-2 and TGF-(31 interacted together to mediate the corneal biology behavior when the cornea was subjected to proper mechanical stimulation.