新型过氧化物酶peroxiredoxin-1对大鼠肺成纤维细胞JNK介导的Ⅰ和Ⅲ型前胶原合成的影响

Effect of peroxiredoxin-1 on JNK-involved collagen type Ⅰ and Ⅲ expressions in TGF-β1-induced pulmonary fibroblasts

目的：探讨活性氧（ROS）在转化生长因子（TGF-β1）激活c-Jun N末端激酶（JNK）促进肺成纤维细胞合成Ⅰ和Ⅲ型前胶原过程中的作用,并观察新型过氧化物酶peroxiredoxin-1 （Prx-1）是否通过抑制活性氧来抑制TGF-β1促纤维化作用.方法：采用脂质体转染法转染真核质粒;免疫荧光检测质粒转染和8-OHdG（DNA氧化产物）的水平;免疫印迹检测Ⅰ/Ⅲ型前胶原、磷酸化JNK和Prx-1的表达.结果：与对照组比较,TGF-β1组的Ⅰ/Ⅲ型前胶原、8-OHdG及磷酸化p-JNK的表达水平均明显增加.与TGF-p1组比较,空载体组中的上述观察指标无明显变化,但Prx-1转染组的指标均明显下降.结论：TGF-β1能够诱导肺成纤维细胞生成活性氧,并由此促进JNK的激活和Ⅰ/Ⅲ型前胶原合成增加,而Prx-1则通过抑制活性氧来抑制TGF-β1的促纤维化作用.

Objective： To explore the effect of reactive oxygen species （ROS） on TGF-β1-induced c-Jun N-terminal kinase （JNK） activation and collagen synthesis in cultured pulmonary fibroblasts, and to study whether peroxiredoxin-1 （Prx-1, a noval type of peroxidase） can inhibit these changes by decreasing ROS level. Methods： Prx-1 was transfected into pulmonary fibroblasts using the liposome infection. Immunofluorescence was used to evaluate plasmid transfection and 8-OHdG level; while the expressions of collagen type I and IN, phosphorylated JNK （p-JNK） and Prx-1 were measured by Western blotting. Results： The plasmids were successfully transfected into pulmonary fibroblasts, showing as green flurescence in cytoplasm and increased expression of Prx-1 protein compared with control （no plasmid） and negative control （plasmid without prx-1 gene）. TGF-β1 significantly stimulated the expressions of collagen type I and Ⅲ, p-JNK and 8-OHdG in pulmonary fibroblasts, which could be markedly inhibited by Prx-1 plasmid transfection but not in the vehicle group. Conclusion： TGF-β1 induces pulmonary fibroblasts to generate ROS, which contributes to JNK activation and increases collagen synthesis; however, Prx-1 overexpression inhibits these changes by decreasing ROS level.