Jia Hong-Zhen, Pang Xu, Peng Xiu-Jun
Department of Ophthalmology, the Sixth Medical Center of Chinese PLA General Hospital, Beijing 100048, China.
Int J Ophthalmol. 2021 Jan 18;14(1):26-31. doi: 10.18240/ijo.2021.01.04. eCollection 2021.
To observe changes in the content of matrix metalloproteinases (MMPs) in the corneal stroma after corneal cross-linking (CXL) in rabbits, and further explore the corneal pathophysiological process after CXL.
Forty-two rabbits (42 eyes) were randomly divided into seven groups. One group served as the control group, while the other six groups were treated with CXL. The concentrations of MMPs in corneal stroma were evaluated through parallel reaction monitoring at baseline and 3, 7, 15, 30, 90, and 180d after treatment.
The levels of MMP-2 in the corneal stroma of rabbits were 0.76±0.07, 2.78±1.39, 4.12±0.69, 2.00±0.29, 2.00±0.30, 1.22±0.18, and 1.35±0.18 (10 mol/g) at baseline and 3, 7, 15, 30, 90, and 180d after treatment, respectively. The contents of tissue inhibitor of metalloproteinase-1 (TIMP-1) were 1.83±0.26, 7.94±0.58, 6.95±2.64, 3.81±0.48, 3.07±0.92, 1.72±0.19, and 1.69±0.74 (10 mol/g), respectively. The ratios of MMP-2/TIMP-1 were 0.42±0.33, 0.36±0.20, 0.62±0.10, 0.54±0.15, 0.68±0.13, 0.71±0.10, and 0.68±0.09, respectively. After CXL, the expression of MMP-2 and TIMP-1 in the rabbit corneal stroma was initially increased and subsequently decreased. The levels of MMP-2 remained higher than those recorded at baseline 180d after treatment, but it was not statistically significant. The levels of TIMP-1 returned to baseline levels at 90d after treatment. The ratio of MMP-2/TIMP-1 started to rise from 7d after CXL. It was significantly higher than that calculated at baseline 30-180d after CXL. The results for MMP-1, -3, -7, -9, -13, and TIMP-2 were negative.
CXL can lead to changes in the content of MMP-2 and TIMP-1 in the rabbit corneal stroma. The ratio of MMP-2/TIMP-1 remains higher versus baseline, indicating that MMP-2 is involved in the corneal pathophysiological process after CXL.
观察兔角膜交联（CXL）术后角膜基质中基质金属蛋白酶（MMPs）含量的变化，进一步探讨CXL术后角膜的病理生理过程。
42只兔（42只眼）随机分为7组。1组作为对照组，其他6组行CXL治疗。通过平行反应监测评估治疗前及治疗后3、7、15、30、90和180天兔角膜基质中MMPs的浓度。
兔角膜基质中MMP-2水平在治疗前及治疗后3、7、15、30、90和180天分别为0.76±0.07、2.78±1.39、4.12±0.69、2.00±0.29、2.00±0.30、1.22±0.18和1.35±0.18（10⁻⁹mol/g）。基质金属蛋白酶组织抑制因子-1（TIMP-1）含量分别为1.83±0.26、7.94±0.58、6.95±2.64、3.81±0.48、3.07±0.92、1.72±0.19和1.69±0.74（10⁻⁹mol/g）。MMP-2/TIMP-1比值分别为0.42±0.33、0.36±0.20、0.62±0.10、0.54±0.15、0.68±0.13、0.71±0.10和0.68±0.09。CXL术后，兔角膜基质中MMP-2和TIMP-1的表达先升高后降低。治疗后180天MMP-2水平仍高于治疗前，但差异无统计学意义。TIMP-1水平在治疗后90天恢复至基线水平。MMP-2/TIMP-1比值从CXL术后7天开始升高。在CXL术后30 - 180天显著高于治疗前计算值。MMP-1、-3、-7、-9、-13和TIMP-2的检测结果为阴性。
CXL可导致兔角膜基质中MMP-2和TIMP-1含量发生变化。MMP-2/TIMP-1比值高于基线水平，表明MMP-2参与了CXL术后角膜的病理生理过程。
