染料木素保护血管紧张素Ⅱ致高血压小鼠心脏纤维化

Effects of genistein on cardiac fibrosis of hypertensive mice induced by angiotensin Ⅱ

目的探讨染料木素在血管紧张素Ⅱ(AngⅡ)诱导的高血压小鼠心脏纤维化中的作用。方法 30只雄性C57BL/6J小鼠随机分为对照组、AngⅡ组、AngⅡ+染料木素组,每组10例。AngⅡ组以1 500 ng·kg-1·min-1连续泵入4.32μg/μl AngⅡ7 d,AngⅡ+染料木素组在AngⅡ泵入前5 d开始皮下注射染料木素0.1μmol/kg,持续至AngⅡ泵入结束,对照组以乙酸代替AngⅡ泵入。心脏超声检测3组小鼠心功能的改变,病理染色检测心脏纤维化程度,实时定量PCR检测collagenⅠα、collagenⅢ、MMP-9、TGF-β1的mRNA表达量的变化,Western Blot检测3组小鼠心脏自噬的改变。结果染料木素可明显改善心功能,减轻AngⅡ诱导的心脏纤维化程度,AngⅡ+染料木素组LVEF和LVFS与AngⅡ组相比增加,且舒张期E峰运动速率升高(P<0.05),实时定量PCR检测显示AngⅡ+染料木素组collagenⅠα、collagenⅢ、MMP-9、TGF-β1的mRNA表达量较AngⅡ组显著降低(P<0.05),Western-blot检测结果显示,AngⅡ处理能增加心脏自噬标志物LC3的蛋白表达(P<0.05),而染料木素可显著减轻ISO导致的LC3Ⅱ表达量的增加(P<0.05)。结论染料木素能减轻AngⅡ诱导的心脏纤维化,其主要是通过降低AngⅡ诱导的心脏自噬而发挥作用的。

Objective To investigate the effects of genistein on cardiac fibrosis of hypertensive mice induced by angiotensin Ⅱ（ Ang Ⅱ）. Methods Thirty male C57 BL /6J mice were randomly divided into control group,Ang II group and Ang Ⅱ ＋ genistein group,with 10 mice in each group. The animal models with cardiac fibrosis were induced by subcutaneous continuous pumping with Ang Ⅱ 1500 ng / kg for 7 days,however,the mice in Ang Ⅱ ＋ genistein group were injected subcutaneously with genistein 0. 1μmol / kg on 5 days before pumping Ang Ⅱ,continuously to the end of pumping Ang Ⅱ.The mice in control group were given ethanoic acid instead of pumping Ang Ⅱ. Then the changes of cardiac function of the mice were detected by cardiac echo-cardiography,the severity of cardiac fibrosis was determined by pathological staining,the expression levels of collagen Ⅰ α,collagen Ⅲ,MMP-9,TGF-β1mRNA were measured by Real- time PCR,moreover,the changes of cardiac autophagy were detected by Western Blot for three groups. Results Genistein could obviously improve the cardiac function of mice and relieve the severity of cardiac fibrosis induced by genistein. As compared with those in Ang Ⅱgroup,the LVEF and LVFS in Ang Ⅱ ＋ genistein group were increased,furthermore,E peak motion velocity during diastole was significantly increased（ P〈0. 05）. The expression levels of collagen Ⅰα,collagen Ⅲ,MMP-9 and TGF-β1 mRNA in Ang Ⅱ ＋ genistein group were significantly decreased,as compared with those in Ang Ⅱ group（ P〈0. 05）. The results by Western Blot showed that Ang Ⅱ could obviously enhance the expression levels of cardiac autophagy marker- LC3 protein（ P〈0. 05）,however,genistein could significantly alleviate the increase of expression levels of LC3 Ⅱ caused by ISO（ P〈0. 05）. Conclusion Genistein can alleviate cardiac fibrosis induced by Ang Ⅱ,and its action mechanism is mainly by improving the cardiac autophagy induced by Ang Ⅱ.