大豆异黄酮对血管紧张素Ⅱ诱导大鼠胸主动脉内皮细胞增殖的影响

Inhibitory effects of soy isoflavone on proliferation of rat aortic endothelial cells induced by angiotensin Ⅱ

目的:观察大豆异黄酮对血管紧张素Ⅱ(AngⅡ)诱导大鼠胸主动脉内皮细胞(RAECs)增殖的影响及机制。方法:组织贴块法培养RAECs,AngⅡ刺激RAECs建立细胞增殖模型。采用MTT法检测细胞增殖,观察不同浓度大豆异黄酮、亚硝基-精氨酸甲酯(L-NAME,100μmol/L)对AngⅡ诱导RAECs增殖的影响。硝酸还原酶及化学比色法检测细胞上清液中一氧化氮(NO)、一氧化氮合酶(NOS)、诱导型一氧化氮合酶(iNOS)水平。半定量逆转录聚合酶链反应(RT-PCR)检测RAECs iNOS mR-NA的表达。结果:大豆异黄酮在0.1～1.0μmol/L呈剂量及时间依赖性抑制RAECs增殖,但可被L-NAME部分抵消;大豆异黄酮能升高NO、NOS和iNOS水平,增加iNOS mRNA的表达。结论:大豆异黄酮对AngⅡ诱导的RAECs增殖有抑制作用;而上调iNOS基因表达,升高NO水平可能是其发挥作用的机制。

Objective：To investigate the effects of soy isoflavone on the proliferation of primary cultured rat aortic endothelial cells （RAECs） induced by angiotensin Ⅱ. Methods：RAECs were cultured by tissue sticking method. Cell proliferation model was established by stimulation with AngⅡ. Cell proliferation was measured by MTT assay to observe the effects of various concentrations of soy isoflavone and NG-nitro-L-arginine methyl ester （L-NAME,100 μmol / L） on RAECs proliferation induced by Ang Ⅱ. Nitric oxide （NO） level was measured by Griess reagent. Nitric oxide synthase （NOS） and inducible nitric oxide synthase （iNOS） levels were detected by chemical colorimetric method. mRNA expression of iNOS was measured by reverse transcription polymerase chain reaction （RT-PCR）. Results：Soy isoflavone at the doses ranging from 0.1 μmol / L to 1.0 μmol / L inhibited cell proliferation in a dose and time-dependent manner. The inhibitory effects were partly blocked by 100 μmol/L of L-NAME. Soy isoflavone markedly increased NO,NOS and iNOS levels,and increased iNOS mRNA expression in RAECs. Conclusion：Soy isoflavone could inhibit RAECs prolifera tion induced by AngⅡ,and NO might contribute to this inhibitory effects.