中文摘要：

目的：研究转录因子Bach1对人微血管内皮细胞功能的影响。方法：利用小干扰RNA（small interfering RNA,siRNA）细胞转染技术下调内皮细胞Bach1表达;用Matrigel管腔形成实验检测内皮细胞体外血管新生的能力;用Transwell小室法检测细胞迁移;用CCK-8法测定细胞增殖;用实时荧光定量PCR、Western blotting和ELISA法检测细胞中血红素氧合酶1（heme oxygenase 1,HO-1）和血管内皮细胞生长因子（vascular endothelial growth factor,VEGF）mRNA和蛋白的表达情况;用转染报告基因的方法检测VEGF基因的转录活性。结果：下调内皮细胞Bach1表达明显促进人微血管内皮细胞迁移和管腔形成能力,对内皮细胞增殖能力无明显影响;抑制Bach1表达促进内皮细胞HO-1 mRNA和蛋白的表达,增加VEGF转录活性及mRNA和蛋白的表达。结论：抑制转录因子Bach1表达可增加内皮细胞HO-1和VEGF的表达,促进人微血管内皮细胞迁移和管腔形成,提示Bach1是负性调控血管新生的因子。

英文摘要：

AIM： To determine the role of transcription factor Bachl in the functions of human microvascular en- dothelial cells （HMVECs）. METHODS ： Bach1 siRNA was transfected into HMVECs to knock down the expression of Bach/. In vitro endothelial cell tube formation assay in Matrigel culture was used as a surrogate assay for angiogenic poten- tial. Migration of HMVECs was determined by using Transwell chambers. Cell proliferation was measured by CCK-8 assay. Real-time PCR, Western blotting, and ELISA were employed to determine mRNA expression and protein level. Reporter as- say was performed to determine vascular endothelial growth factor （VEGF） transcriptional activity. RESULTS： Knockdown of Bach/ expression in HMVECs led to an increase in the tube formation and increased endothelial cell migration ability, whereas it has little effect on cell proliferation. Bach1 silencing increased the mRNA and protein expression of heme oxygen- ase-1 （ HO-1 ）, and enhanced VEGF transcriptional activation, and mRNA and protein expression. CONCLUSION： Bach/ silencing increases HO-1 and VEGF expression, thus promoting the cell migration and tube formation of HMVECs, indicating that Bachl is a repressor for angiogenesis.