siRNA技术对哮喘模型大鼠气道细胞表达TGF-β和ET-1的影响

The Effects of the siRNA Technology on the TGF-βand the ET-1 in the Airway Smooth Muscle Cells of the Asthmatic Rats

目的观察siRNA技术对哮喘大鼠转化生长因子-β(TGF-β)的作用和对内皮素(ET-1)的影响,探讨使用该技术阻断TGF-β表达治疗哮喘的方法。方法采用卵白蛋白致敏的方法复制大鼠哮喘模型,原代培养大鼠的支气管平滑肌细胞,然后使用TGF-β干扰RNA作用于哮喘平滑肌细胞,用PCR方法和Western blot方法检测正常组平滑肌细胞(A组)、哮喘组平滑肌细胞(B组)以及TGF-β小干扰RNA作用后的哮喘组平滑肌细胞(C组)中TGF-β和ET-1的表达情况,并用MTT方法检测不同组细胞的增殖活性。结果哮喘组与正常组相比,肺部组织具有炎症细胞浸润,基底膜增厚明显,褶皱增多,具有明显的哮喘症状。三组细胞中TGF-β和ET-1表达情况的PCR和Western blot结果,C组TGF-β和ET-1的表达量明显低于B组。MTT结果显示,转染48 h后,C组和B组增殖抑制率分别为(72.1±1.1)%和(55.6±1.5)%;转染72 h后,分别为(42.0±1.3)%和(21.4±1.7)%,C组与B组相比差异显著(P<0.05)。结论使用siRNA技术阻断TGF-β的表达可降低哮喘组细胞ET-1的表达,进而抑制细胞增殖,达到治疗哮喘的目的。

Objective To observe the effects of the siRNA technology on the TGF-β and the ET-1 of the asthmatic rats so as to explore the methods to heal asthma.Methods The asthma model was established by ovalbumin（OVA）sensitizing,the asthmatic smooth muscle cells and the normal smooth muscle cells were cultured.Then,role of the siRNA of the TGF-β was made in the asthmatic smooth muscle cells.The expression of TGF-β and ET-1 were detected in the A（the normal smooth muscle cells）,B（the asthmatic smooth muscle cells） and C（the asthmatic smooth muscle cells effected by the siRNA of the TGF-β）.Thereafter,the multiplicational activity of the cells in each group was detected by MTT.Results Compared with the normal rats,in asthma group,there were inflammatory cells infiltration in the lung tissue,increased thickness and increased drape of the basilar membrane.The manifestations of the asthmatic model was obvious.The results of the PCR and the western blot confirmed that the expression of TGF-β and ET-1 in group C were significantly lower than those of the group B.The result of the MTT confirmed that the inhibition ratio of group B and group C were（72.1±1.1）% and（55.6±1.5）% after 48 h;the inhibition ratio of group B and group C were（42.0±1.3）% and（21.4±1.7）% after 72 h.The result of the MTT had a significant difference（P0.05）.Conclusion Using the siRNA technology can block the expression of TGF-β and decrease the expression of ET-1 to inhibit the cell proliferation and heal asthma.