腱糖蛋白-C对大鼠腹腔巨噬细胞活性及其分泌表达基质金属蛋白酶-2,9的影响

Effect of tenascin-C on the activity and expression of matrix metalloproteinase-2,9 in rat peritoneal macrophages

目的 探讨腱糖蛋白 (tenascin C)对大鼠腹腔巨噬细胞活性及分泌表达基质金属蛋白(MMPs)的影响。方法 分别在tenascin C、纤维连接蛋白 (fibronectin)和tenascin C +fibronectin包被的培养板中 ,采用MTT、Zymography、Western和Northernblot法检测大鼠腹腔巨噬细胞的活性 ,以及MMP 2 ,9活性、蛋白和mRNA水平的表达。结果 Tenascin C不但使巨噬细胞活性增加 ,而且可上调其MMP 9蛋白和mRNA的表达 ,并显著增加MMP9的活性 ,但对MMP 2无明显影响 ;而浓度相同的fibronectin ,对MMP 2 ,9活性及蛋白和mRNA的表达都无明显影响。tenascin C +fibronectin组 ,对MMP 9表达及活性的上调要明显高于tenascin C组 ,说明tenascin C和fibronectin具有协同作用。结论 tenascin C可能具有与其他细胞外基质糖蛋白不同的作用 ,推测动脉粥样硬化病变中tenascin C表达的上调 ,可能会通过增加巨噬细胞的活性并上调MMP 9的表达削弱斑块的稳定性。

Objective To investigate the effect of tenascin-C on the activity and expression of matrix metalloproteinase-2,9 in rat peritoneal macrophages. Methods In vitro, the rat peritoneal macrophages were harvested and cultured in matrix-coated plates for 24-48h. Furthermore, by MTT, Western blot, SDS-PAGE Zymography and Northern blot analysis, we investigated the effects of tenascin-C, fibronectin and tenascin-C+fibronectin on the activity of rat peritoneal macrophages, the expression levels and activity of MMP-2, MMP-9 in rat peritonealmacrophages. Results Tenascin-C increased the activity of macrophages. It not only induced the expression levels of MMP-9 protein and mRNA, but also increased the activity of MMP-9. Fibronectin had no effect on these.Conclusions The results suggested that tenascin-C may have different action from other extracellular matrix glycoproteins. The up-regulation of tenascin-C in atherosclerotic lesion may increase its vulnerability to rupture by increasing the activity of macrophages and their expression of MMP-9.