摘要
目的 探讨黄芪甲苷(Astragaloside IV,AsIV)通过钙离子/钙调蛋白依赖性蛋白激酶激酶β(CaMkkβ)/腺苷酸激活蛋白激酶(AMPK)通路对急性心力衰竭(心衰)大鼠心肌细胞线粒体自噬的影响及作用机制。方法 50只SD大鼠分为对照组(羧甲基纤维素钠)、急性心衰组(羧甲基纤维素钠)、AsIV低、中、高剂量组(20、40、80 mg/kg AsIV羧甲基纤维素钠溶液),每组10只,1次/d,连续灌胃给药7 d,第8天一次性腹腔注射盐酸阿霉素10 mg/kg建立急性心力衰竭模型,24 h后处死,检测各组血清脑钠肽(BNP)、心肌肌钙蛋白T(cTn-T)、丙二醛(MDA)水平,TUNEL法检测心肌细胞凋亡率,透射电镜观察自噬体数目,Western blot法检测自噬相关蛋白(Beclin1、LC3、p62)及CaMkkβ/AMPK信号通路相关蛋白表达量。结果 与对照组比较,急性心衰组血清BNP、cTn-T、MDA水平、心肌细胞凋亡率、心肌细胞线粒体内自噬体数目及心肌组织Beclin1、LC3蛋白表达量及p-CaMkkβ/CaMkkβ、p-AMPK/AMPK均升高(P<0.05);与急性心衰组比较,AsIV低剂量组、AsIV中剂量组及AsIV高剂量组血清BNP、cTn-T、MDA水平、心肌细胞凋亡率、心肌细胞线粒体内自噬体数目及心肌组织Beclin1、LC3蛋白表达量及p-CaMkkβ/CaMkkβ、p-AMPK/AMPK均降低(P<0.05),其中AsIV高剂量组低于AsIV中剂量组,AsIV中剂量组低于AsIV低剂量组(P<0.05)。与对照组比较,急性心衰组心肌组织p62相对表达量降低(P<0.05);与急性心衰组比较,AsIV低剂量组、AsIV中剂量组及AsIV高剂量组心肌组织p62相对表达量均升高,其中AsIV高剂量组高于AsIV中剂量组,AsIV中剂量组高于AsIV低剂量组(P<0.05)。结论 黄芪甲苷可有效抑制急性心衰大鼠心肌细胞线粒体自噬的形成,抑制心肌细胞凋亡,其调控机制可能与CaMkkβ/AMPK信号通路有关。
Objective To explore the effect and mechanism of astragaloside IV(AsIV)on mitochondrial autophagy in myocardial cells of rats with acute heart failure through the calcium ion/calmodulin-dependent protein kinase kinaseβ(CaMkkβ)/adenylate activated protein kinase(AMPK)pathway.Methods Fifty SD rats were divided into control group(sodium carboxymethylcellulose),acute heart failure group(sodium carboxymethylcellulose),AsIV low,medium and high dose groups(20,40,80 mg/kg astragaloside IV Glycoside carboxymethyl cellulose sodium solution),each group of 10,once a day,continuous intragastric administration for 7 days.On the 8th day,a one-time intraperitoneal injection of 10 mg/kg of doxorubicin hydrochloride was performed to establish an acute heart failure model,and it was sacrificed 24 hours later.The serum brain natriuretic peptide(BNP),cardiac troponin T(cTn-T),and malondialde⁃hyde(MDA)levels were detected in each group.Cardiomyocyte apoptosis rate was detected by TUNEL method.The number of autophagosomes was observed by transmission electron microscope.The expressions of autophagy-related proteins(Beclin1,LC3,p62)and CaMkkβ/AMPK signaling pathway related proteins were detected by Western blot.Results Compared with the control group,the levels of serum BNP,cTn-T,MDA,myocardial cell apoptosis rate,the number of autophagosomes in myocardial cell mitochondria and the expression of Beclin1,LC3 protein and p-CaMkkβ/CaMkkβ,p-AMPK/AMPK in myocardial tissue all increased(P<0.05).Compared with acute heart failure group,the levels of serum BNP,cTn-T,MDA,myocardial cell apoptosis rate,the number of autophagosomes in myo⁃cardial cell mitochondria and the expression of Beclin1,LC3 protein and p-CaMkkβ/CaMkkβ,p-AMPK/AMPK in myocardial tissue in the AsIV low-dose group,AsIV medium-dose group and AsIV high-dose group were reduced were all decreased(P<0.05),among which AsIV high-dose group was lower than AsIV medium-dose group,AsIV middle-dose group was lower than AsIV low-dose group(P<0.05).Compared with the control group,the relative expression of p62 in the myocardial tissue of the acute heart failure group decreased(P<0.05).Compared with the acute heart failure group,the relative expression of p62 in myocardial tissues increased in the low-dose AsIV group,the middle-dose AsIV group and the high-dose AsIV group(P<0.05),among which the AsIV high-dose group was high⁃er than AsIV medium-dose group,AsIV middle-dose group was higher than AsIV low-dose group(P<0.05).Conclusion Astragaloside IV can effectively inhibit the formation of mitochondrial autophagy and apoptosis of cardiomyo⁃cytes in rats with acute heart failure.Its regulatory mechanism may be related to the CaMkkβ/AMPK signaling pathway.
作者
任欣伟
张卫国
聂玉真
REN Xin-wei;ZHANG Wei-guo;NIE Yu-zhen(Department of Cardiovascular Medicine,the Second Affiliated Hospital of Zhengzhou University,Zhengzhou 450053,China)
出处
《医药论坛杂志》
2023年第9期41-46,共6页
Journal of Medical Forum
