细胞外信号调节激酶1/2通路在Peroxiredoxin-1抑制转化生长因子-β_1诱导的Ⅰ、Ⅲ型胶原蛋白表达中的作用

Effect of ERK1/2 on inhibition of TGF-β_1-induced expressions of collagen type Ⅰ and Ⅲ by peroxiredoxin-1 in pulmonary fibroblasts

目的探讨细胞外信号调节激酶1/2(ERK1/2)在转化生长因子-β1(TGF-β1)诱导的肺成纤维细胞合成Ⅰ、Ⅲ型胶原蛋白中的作用,及新型过氧化物酶Peroxiredoxin-1(Prx-1)对该作用的影响。方法体外培养肺成纤维细胞随机分为4组:对照组(0.4%血清)、TGF-β1组(5μg/L)、阴性转染组(TGF-β1+阴性对照si RNA)和Prx-1 si RNA转染组(TGF-β1+Prx-1 si RNA)。采用脂质体转染法转染si RNA,实时定量逆转录-聚合酶链反应(RT-PCR)检测转染后Prx-1 m RNA表达;Western blot检测Ⅰ和Ⅲ型胶原蛋白、ERK1/2及Prx-1表达;2,7-二氯荧光素二乙酸(DCFH-DA)检测活性氧(ROS)水平。结果 Prx-1 si RNA转染肺成纤维细胞后,Prx-1 m RNA表达明显降低,最大抑制率为92%。与对照组比较,TGF-β1组的Ⅰ和Ⅲ型胶原蛋白、ROS、磷酸化ERK1/2(p-ERK1/2)及Prx-1蛋白的表达水平均明显提高。与TGF-β1组比较,阴性转染组中的上述观察指标无明显变化,但Prx-1转染组的Ⅰ和Ⅲ型胶原蛋白、ROS、p-ERK1/2水平进一步提高,而Prx-1蛋白的表达被抑制。结论 TGF-β1能够诱导肺成纤维细胞生成ROS,并促进ERK1/2通路的激活,导致Ⅰ、Ⅲ型胶原蛋白合成增加,而Prx-1 si RNA可通过提高ROS水平进一步促进TGF-β1该作用。

【Objective】 To investigate whether extracellular signal-regulated kinase 1/2（ERK1/2） mediates the inhibiting effect of peroxiredoxin-1（Prx-1） on collagen type Ⅰ and Ⅲ expressions induced by transforming growth factro-β1（TGF-β1） in pulmonary fibroblasts. 【Methods】 Cultured pulmonary fibroblasts were randomly divided into four groups： control（0.4% serum）, TGF-β1（5 μg/L）, TGF-β1＋ scramble si RNA and TGF-β1＋ Prx-1 si RNA. Scramble si RNA or Prx-1 si RNA was transfected into pulmonary fibroblasts using the liposome infection. Real-time PCR was used to evaluate Prx-1 m RNA and Western blot was to dectect the expressions of collagen type Ⅰ and Ⅲ, phosphorylated ERK1/2（p-ERK1/2） and Prx-1. DCFH-DA assay was to detect reactive oxygen species（ROS） level. 【Results】 Prx-1 si RNA successfully decreased the Prx-1 m RNA expression compared with the controls. TGF-β1significantly stimulated the expressions of collagen type Ⅰ andⅢ, p-ERK1/2 and ROS in pulmonary fibroblasts, which became more obvious by Prx-1 si RNA treatment but not scramble si RNA. In addition, Prx-1 si RNA decreased Prx-1 protein expression induced by TGF-β1.【Conclusions】TGF-β1induces pulmonary fibroblasts to generate ROS, which contributes to ERK1/2 activation and synthesis of collagen type Ⅰ and Ⅲ. These changes become more obvious with Prx-1 si RNA treatment.