转化生长因子β1对L929细胞增殖转分化及细胞外基质代谢的影响

目的 探讨转化生长因子β1(transforming growth factor-β1,TGF-β1)对L929细胞增殖的影响,为体外研究预防食管内镜黏膜下剥离术(endoscopic submucosal dissection,ESD)术后狭窄提供理论基础.方法 实验分为两组,①空白对照组:L929细胞不做处理;②TGF-β1组,用10 ng/mL TGF-β1 持续刺激L929细胞,依据刺激时间不同又分为24、48、72、96、120 h 5个亚组.观察各组对细胞增殖的影响.用CCK-8法检测细胞增殖,qPCR检测α-SMA及Ⅰ型前胶原、Ⅲ型前胶原、MMP1、TIMP1 mRNA 表达,Western blot检测α-SMA、MMP1、TIMP1蛋白水平,ELISA检测Ⅰ型前胶原、Ⅲ型前胶原合成.结果 与空白对照组比较,TGF-β1组细胞增殖能力显著增高(P＜0.05),TGF-β1组α-SMA、Ⅰ型前胶原、Ⅲ型前胶原、MMP1、TIMP1 mRNA表达均显著升高(P＜0.05);TGF-β1刺激24 h组Ⅰ型前胶原合成增加(P＜0.05),TGF-β1组Ⅲ型前胶原合成增加(P＜0.05);TGF-β1组MMP1、TIMP1蛋白表达增加(P＜0.05).结论 TGF-β1能促进L929细胞增殖,并诱导L929细胞向肌成纤维细胞转分化,同时促进Ⅰ型前胶原、Ⅲ型前胶原以及MMP1、TIMP1合成.

Effects of TGF-β1 on transdifferentiation and extracellular matrix synthesis in L929 cells

Objective To investigate the effect of TGF-β1 on the growth of L929 cells in order to found the basis for theoretical study on prevention of esophageal stricture after endoscopic submucosal dissection.Methods Experiments had two sets:a control group without any treatments and a TGF-β1 treatment group in which cells were treated with 10 ng/mL TGF-β1.According to the time of stimulation by TGF-β1, subgroups were set as 24, 48, 72, 96 and 120 h treatment groups, the cell proliferation were measured with CCK-8 assay in every group of cells.qPCR was used to detect the mRNA expression of α-SMA and procollagen type Ⅰ (Col Ⅰ) and Ⅲ (Col Ⅲ), matrix metalloproteinase 1 (MMP1), tissue inhibitor of metalloprotein 1 (TIMP1).Western blotting was employed for protein levels of α-SMA, MMP1 and TIMP1.ELISA was adopted to measure the synthesis of Col Ⅰ and Col Ⅲ.Results Compared with the blank control cells, TGF-β1 treatment significantly promote cell proliferation (P ＜ 0.05), and enhanced the mRNA levels of α-SMA, Col Ⅰ, Col Ⅲ, MMP1 and TIMP1 in L929 cells (P ＜ 0.05).TGF-β1 stimulation for 24 h increased the syntheses of Col Ⅰ (P ＜ 0.05) and Col Ⅲ (P ＜ 0.05), and protein level of MMP1.The treatment for 96 and 120 h also enhanced the protein level of TIMP1 (P ＜0.05).Conclusion TGF-β1 can promote the proliferation of L929 cells, induce the transformation of L929 cells into myofibroblasts, and improve the syntheses of Col Ⅰ, Col Ⅲ, MMP1 and TIMP1.