目的 探讨转化生长因子-β1(TGF-β1)对人主动脉平滑肌细胞(HA-VSMC)表型转化的影响及其机制.方法 HA-VSMC分为3组培养:空白对照组、TGF-β1组、TGF-β1抑制剂组;细胞计数试剂盒(CCK-8)、Transwell实验检测各组细胞增殖、迁移能力,考马斯亮蓝染色检测其骨架形态;实时荧光定量聚合酶链反应(FQ-PCR)及Western blot检测其DNA结合抑制因子2(ID2)、平滑肌22α(SM22α)、α-平滑肌肌动蛋白(α-SMA)、骨桥蛋白(OPN) mRNA及蛋白表达.结果 与空白对照组比较,TGF-β1组增殖及迁移细胞数均明显增多[吸光度值:2.438±0.038比2.157±0.080,P<0.01;迁移细胞数:(30.667±3.786)个比(21.667±4.509)个,P<0.05].考马斯亮蓝染色结果显示,TGF-β1组细胞多为肥胖型且呈峰谷状;而其余两组多呈细长梭形.TGF-β1组ID2、OPNmRNA及蛋白表达明显高于空白对照组[ID2 mRNA:1.363±0.080比0.980±0.104;OPN mRNA:1.528±0.092比1.100±0.106;ID2蛋白:0.566±0.067比0.273±0.039;OPN蛋白:0.548±0.031比0.289±0.042],而α-SMA、SM22α的mRNA及蛋白较空白对照组表达降低[α-SMA mRNA:0.666±0.011比0.994±0.010;SM22α mRNA:0.622±0.067比0.881±0.066;α-SMA蛋白:0.059±0.012比0.263±0.021;SM22α蛋白:0.063±0.011比0.301±0.041];TGF-β1抑制剂组较空白对照组ID2、OPN mRNA及蛋白表达降低[ID2 mRNA:0.503±0.091比0.980±0.104;OPN mRNA:0.786±0.098比1.100±0.106;ID2蛋白:0.148±0.020比0.273±0.039;OPN蛋白:0.168±0.020比0.289±0.042],α-SMA、SM22α mRNA及蛋白表达升高[α-SMA mRNA:1.217±0.026比0.994±0.010;SM22α mRNA:1.137±0.162比0.881±0.066;α-SMA蛋白:0.422±0.027比0.263±0.021;SM22α蛋白:0.488±0.068比0.301±0.041](P<0.05).结论 TGF-β1可诱导人主动脉平滑肌细胞发生由收缩型向合成型的转化,该作用可能与TGF-β1上调了ID2表达水平有关.
Objective To study the effect of transforming growth factor-β1 (TGF-β1) on human aortic vascular smooth muscle cells (HA-VSMCs) phenotype switch and the mechanism.Methods HA-VSMCs were divided into three groups : blank control group, TGF-β1 group, and TGF-β1 inhibitor group.Cell proliferation and migration of each group were detected by cell counting kit-8 (CCK-8) and Transwell assay, respectively.Cytoskeleton shapes of groups were observed by coomassie brilliant blue staining.Real-time fluorescent quantitative polymerase chain reaction (FQ-PCR) and Western blotting were used to detect the expression of DNA binding inhibitory factor 2 (ID2), smooth muscle 22α (SM22α), and α-smooth muscle actin (α-SMA) and osteopontin (OPN), respectively.Results Cell proliferation and migration of TGF-β1 group were increased as compared with blank control group (OD value: 2.438 ± 0.038 vs.2.157 ± 0.080, P < 0.01;migrating cells: 30.667 ± 3.786 vs.21.667 ± 4.509, P < 0.05).Coomassie brilliant blue staining that cells in TGF-β1 group had hypertrophic apprearance and "hill and valley" growth, and those in other groups had spindle elongated morphology.In addition, the expression of ID2 and OPN mRNA and protein in TGF-β1 group was stronger than blank control group [ID2 mRNA: 1.363 ±0.080 vs.0.980±0.104;OPN mRNA: 1.528 ±0.092 vs.1.100±0.106;ID2 : 0.566 ± 0.067 vs.0.273 ± 0.039;OPN : 0.548 ± 0.031 vs.0.289 ± 0.042], while that of α-SMA and SM22α was weaker than blank control group [α-SMA mRNA: 0.666 ± 0.011 vs.0.994 ± 0.010;SM22α mRNA: 0.622 ±0.067 vs.0.881 ±0.066;α-SMA: 0.059 ±0.012 vs.0.263 ± 0.021;SM22α: 0.063 ± 0.011 vs.0.301 ± 0.041].The expression levels of ID2 and OPN mRNA and protein in TGF-β1 inhibitor group were lower than in blank control group [ID2 mRNA: 0.503 ±0.091 vs.0.980 ±0.104;OPN mRNA: 0.786 ±0.098 vs.1.100 ±0.106;ID2: 0.148 ±0.020 vs.0.273 ± 0.039;OPN : 0.168 ±0.020 vs.0.289 ±0.042], while those of α-SMA and SM22α were higher than in blank control group [α-SMA mRNA: 1.217 ±0.026 vs.0.994 ±0.010;SM22c mRNA: 1.137 ± 0.162 vs.0.881 ± 0.066;α-SMA : 0.422 ± 0.027 vs.0.263 ± 0.021;SM22α : 0.488 ± 0.068 vs.0.301 ± 0.041] (P < 0.05).Conclusion TGF-β1 can induce HA-VSMCs to switch from a contractile to synthetic phenotype, which may be related to up-regulation of the ID2 expression.