距骨骨软骨损伤MR T2-mapping与软骨基质金属蛋白酶-1表达的相关性研究

The correlation between the expression of matrix metalloproteinase-1 and magnetic resonance T2-mapping in talus osteochondral injury

目的探讨距骨骨软骨损伤(osteochondral lesions of the talus,OLT)软骨基质金属蛋白酶-1(matrix metalloproteinase-1,MMP-1)的表达与磁共振T2值之间的关系及其在距骨骨软骨损伤的机制。材料与方法收集30例踝关节距骨骨软骨损伤行微创治疗术患者及30名健康志愿者,均行3.0 T常规踝关节磁共振成像(magnetic resonance imaging,MRI)及T2-mapping功能成像,测量距骨软骨T2值。术后离体距骨骨软骨行苏木精-伊红染色(hematoxylin-eosin staining,HE)和Western Blot法分析距骨骨软骨MMP-1的表达,统计学分析距骨骨软骨T2值与MMP-1蛋白表达的相关性。结果距骨骨软骨损伤以内中侧最为多见(磁共振6分区法),距骨骨软骨T2值随软骨损伤Mankin分级明显增大(P<0.05)。软骨MMP-1蛋白表达高级别与低级别差异明显(P<0.05)。软骨T2值与软骨MMP-1表达呈线性相关趋势,Pearson分析距骨骨软骨损伤T2值增加与MMP-1蛋白表达增加呈直线性正相关(r=0.821,P<0.0001)。结论距骨骨软骨损伤以内中侧最为多见,距骨骨软骨磁共振T2值随软骨损伤分级逐级递增;距骨骨软骨损伤磁共振T2值与MMP-1蛋白表达呈正相关,距骨骨软骨磁共振T2-mapping功能成像T2值定量分析可在体、无创性预测不同级别软骨损伤MMP-1蛋白的表达含量,为临床治疗OLT提供影像学定量依据。

Objective:To investigate the relationship between the expression of matrix metalloproteinase-1(MMP-1)and magnetic resonance(MR)T2 value and its mechanism in talus osteochondral injury(OLT).Materials and Methods:Thirty cases of ankle OLT patients under minimally invasive therapy and 30 healthy volunteers were collected.3.0 T routine MR and T2-mapping scans were performed and T2 values were measured.The HE staining of the talus cartilage during the operation were used and the Western Blot method were used to measure the expression of MMP-1.The correlation between the T2 value of MR and the content of MMP-1 was statistically analyzed.Results:OLT was most common in the medial central of the talus(MRI 6 zoning method).The T2 value increased with the severity of the cartilage degeneration under Mankin grade,and the difference was statistically significant(P<0.05).The expression of MMP-1 was significantly different between high-grade and low-grade(P<0.05).The cartilage T2 value and MMP-1 expression showed a linear trend.Pearson correlation analysis showed a linear positive correlation between the two(r=0.821,P<0.0001).Conclusions:OLT is most common in the medial central side of the talus.The T2 value of MRI increased with the degrade of cartilage injury.The T2 value of OLT showed a positive correlation with the determination of MMP-1.T2-mapping functional imaging could provide a quantitative imaging basis for clinical treatment of OLT by predict the expression of MMP-1 protein in different grades of cartilage injury in vivo and noninvasion.