基质金属蛋白酶-8对角膜基质胶原的作用研究

目的 探讨基质金属蛋白酶-8(MMP-8)对角膜的作用.方法 选取健康C57BL/6J小鼠15只,右眼角膜基质内注射10μL MMP-8作为实验组,左眼给予等量生理盐水作为对照组.于0、4、8h使用双光子显微镜二次谐波成像技术对活体小鼠角膜逐层扫描,Imaris软件对所得图像三维重建,计算图像信号强度.4、8h在裂隙灯下评价角膜混浊度.8h角膜取材,测定各角膜羟脯氨酸水平.结果 0h实验组及对照组小鼠角膜基质纤维信号强度分别为89.7±11.2、85.3±7.0,4h分别为14.5± 3.4、46.6±14.0,8h分别为11.0±4.6、34.6±12.5,4h及8h,实验组较对照组角膜基质信号强度明显降低(P<0.05);4h及8h,实验组较对照组角膜明显混浊(P<0.05);8 h测得实验组与对照组角膜羟脯氨酸水平分别为(0. 433±0.090)、(0. 590± 0. 133)μg/mg,实验组明显低于对照组(F=7. 193,P=0. 014).结论 MMP-8对小鼠角膜基质胶原有明显的降解破坏作用,导致角膜透明度下降.

Effect of MMP-8 on cornea collagen

Objective To investigate the effect of MMP-8 on cornea. Methods Fifteen C57BL/6J healthy mice were selected. The right eyes corneal stroma was injected by 10μL MMP-8 as the experimental group and the left eyes were injected by same amount of normal saline as the control group. At 0,4,8 h, the two-photon microscope second harmonic generation imaging technology was used to scan mice corneal stroma layer by layer in vivo. The obtained images were performed the 3D reconstruction by Imaris software and the signal intensity of the images were calculated. At 4,8 h, the corneal opacity degree was evaluated under slit lamp. At 8 h,mice were killed and corneas were collected to determine the hydroxyproline concentration. Results The cornea stromal fiber signal strengthes at 0 h in the experimental group and control group were (89.7±11.2) and (85.3±7.0),which at 4 h were (14.5±3.4) and (46.6±14. 0) respectively,which at 8 h were (11.0±4.6) and (34.6±12.5) respectively. The cornea stromal signal strength at 4,8 h in the experiemental group was significantly decreased compared with that in the control group (P<0.05) ;the cornea at 4 ,8 h in the experimental group was significantly turbid than that in the control group (P<0.05);the cornea hydroxyproline concentrations detected at 8h in the experiemental group and control group were (0.433±0. 090) μg/mg and (0. 590±0. 133) μg/mg respectively,the experimental group was significantly lower than the control group (F=7. 193,P=0. 014). Conclusion MMP-8 has obvious degradation and destroy effect on mice corneal stroma collagen,which leads to the decrease of corneal opacity.