黄芪甲苷通过CaMKⅡ信号通路对异丙肾上腺素诱导的心肌细胞肥大的保护作用

Protective effect of astragaloside Ⅳ on isoproterenol-induced cardiac hypertrophy through Ca MKⅡ

目的:从钙调素蛋白依赖激酶Ⅱ(Ca MKⅡ)信号通路的角度探讨黄芪甲苷(AsⅣ)对异丙肾上腺素(Iso)诱导乳鼠心肌细胞肥大的保护作用及其可能机制。方法:原代培养新生乳鼠心肌细胞,10 mol/L异丙肾上腺素诱导心肌细胞肥大,观察KN93(Ca MKⅡ抑制剂)、黄芪甲苷3,10,30 mol/L剂量组对肥大细胞的影响。采用消化分离法及计算机图像分析系统检测心肌细胞体积;考马斯亮蓝试剂盒检测心肌细胞中总蛋白含量;罗丹明-鬼笔环肽染色观察细胞骨架;反转录聚合酶链反应(RT-PCR)法检测心房利钠肽(ANP)mRNA表达;Wertern blot检测心肌细胞Ca MKⅡ表达。结果:与正常对照组细胞比较,异丙肾上腺素模型组细胞体积、总蛋白含量、ANPmRNA和Ca MKⅡ表达分别增加98.14%、52.63%、87.37%和55.22%。黄芪甲苷可有效抑制异丙肾上腺素诱导的心肌细胞肥大,黄芪甲苷30 mol/L组可抑制异丙肾上腺素诱导的心肌肥大,使模型组细胞体积减小49.67%、总蛋白含量降低33.87%、ANPmRNA表达降低40.00%,Ca MKⅡ的表达降低31.73%。结论:黄芪甲苷可抑制异丙肾上腺素诱导的心肌细胞肥大,其机制可能与抑制Ca MKⅡ信号通路有关。

Aim： To investigate the protective effect of astragaloside Ⅳ on isoproterenol（ Iso）-induced cardiac hypertrophy through Ca MKⅡ signal pathway in neonatal rats. Methods： The primary cultures of neonatal rat ventricular myocytes were used. The cardiac myocytes hypertrophy model was induced by 10 mol / L Iso. The effect of different concentration of AsⅣ and KN93（ calcium / calmodulin- dependent protein kinaseⅡ inhibitor） on cardiac hypertrophy was observed. The cardiomyocytevolume was measured by computer photograph analysis system,total protein content was measured by Bradford Protein Assay Kit,cytoskeleton were observed by Rhodamin-phalloidin staining,expression of ANP mRNA was determined by RT-PCR,and the expression of Ca MKⅡ was measured by Western blot,respectively. Results： Compared with normal control group,the cell volume,total protein content,expression of ANP mRNA and Ca MKⅡincreased by 98. 14%,52. 63%,87.37% and 55. 22% in Iso-treated group. AsⅣ could inhibit the Iso-induced cardiac hypertrophy by reducing the cardiomyocytes protein content and volume by 49. 67%,33. 87%,40. 00%,31. 73%. Conclusion： AsⅣ had a protective effect on Iso induced cardiac hypertrophy,which is partially via inhibiting the expression of Ca MKⅡ induced by Iso.