17β-雌二醇对雌性大鼠盆底肌成纤维细胞机械应力后的影响

Effect of 17β-estradiol on pelvic myofibroblasts of female rats after mechanical stress

目的研究17β-雌二醇(17-βE2)对特定加力强度的雌性大鼠盆底肌成纤维细胞中基质金属蛋白酶-9(MMP-9)、金属蛋白酶组织抑制剂-1(TIMP-1)及β-联蛋白(β-catenin)的影响。方法原代培养雌性大鼠耻尾肌及周围筋膜并分离成纤维细胞,通过Flexercell 4000系统加载强度为10%、时间为12 h的机械应力,给予17-βE2干预,同时设置对照组(成纤维细胞组)以及机械应力组(强度为10%、时间为12 h的机械应力组)。荧光定量聚合酶链反应(PCR)测量各组MMP-9,TIMP-1及β-catenin m RNA的相对表达量。结果 RT-PCR结果显示,加力组与对照组相比,成纤维细胞中MMP-9 m RNA的相对表达量为2.690±0.020,高于对照组,差异有统计学意义(P<0.05),TIMP-1 m RNA及β-catenin m RNA的相对表达量为0.370±0.010、0.430±0.010,低于对照组,差异有统计学意义(P<0.05),17-βE2干预后,成纤维细胞中MMP-9 m RNA相对表达量为1.523±0.068,高于对照组,低于加力组,差异有统计学意义(P<0.05),TIMP-1 m RNA及β-catenin m RNA的相对表达量为0.600±0.010、0.630±0.010,低于对照组,高于加力组,差异有统计学意义(P<0.05)。结论机械拉伸力可以使细胞形态和伸展方向发生改变,MMP-9表达增加,β-catenin及TIMP-1的表达下降,而17-βE2使得上述应力表现减弱。

Objective To investigate the effects of 17β-estradiol （17β-E2） on matrix metalloproteinase-9 （MMP-9）, tissue inhibitor of metalloproteinase （TIMP-1） and β-catenin in the specific stressed pelvic myofibroblast of female rats. Methods Primary culture of pubococcygeus and peripheral fascia cells of female rats were segregated into fi-broblast. Then, the fibroblast were loaded with 10%mechanical stress for 12 h by Flexercell 4000 tensile loading sys-tem, and intervened with 17β-E2. Meanwhile, the control group （the fibroblast group） and mechanical stress group （10% stress-loaded for 12 h） were set up. The relative expression levels of MMP-9, TIMP-1 and β-catenin mRNA in each group were measured by fluorescent quantitative polymerase chain reaction （PCR）. Results RT-PCR showed that, compared with the control group, higher relative expression level of MMP-9 mRNA （2.690±0.020）, and lower rel-ative expression levels of TIMP-1mRNA and β-catenin mRNA （0.370 ±0.010 and 0.430 ±0.010） in fibroblasts were found in the mechanical stress group, with statistically significant differences （P〈0.05）. After intervened with 17β-E2, the relative expression level of MMP-9 mRNA of fibroblast （1.523±0.068） was higher than that in the control group and lower than that in the mechanical stress group, with statistical difference （ P〈0.05）;whereas the relative expression levels of TIMP-1 mRNA and β-catenin mRNA （0.600±0.010 and 0.630±0.010, respectively） were lower than those in the control group and higher than those in the mechanical stress group, with statistical differences （ P〈0.05）. Conclu-sion Mechanical stress can change the morphology and stretching direction of fibroblasts, increase MMP-9 expres-sion, and decrease β-catenin and TIMP-1 expressions. These effects can be attenuated by 17β-estradiol.