黄芪甲苷减少脓毒症大鼠心肌自噬的实验研究

Effects of astragaloside for reducing myocardial autophagy in the rats with sepsis

目的分析黄芪甲苷对脓毒症大鼠Beclin1、p62和LC3自噬相关基因及蛋白以及心肌自噬情况的影响。方法清洁级雄性Wistar大鼠30只,采用随机数字表法分为空白对照组(Blank组)、生理盐水尾静脉注射组(NS组)、黄芪甲苷尾静脉注射组(黄芪甲苷组) 3组,每组10只。采用盲肠结扎穿孔法制造脓毒症模型。利用RT-PCR技术检测各组大鼠心肌中Beclin1、p62和LC3 mRNA检测水平,Western Blotting技术检测各组大鼠心肌中Beclin1、p62和LC3蛋白表达水平。采用透射电子显微镜观察心肌超微结构及腺泡细胞内自噬小体的形成情况。结果与Blank组相比,NS组大鼠心肌中Beclin1、p62和LC3自噬相关基因及蛋白表达明显升高(P <0. 05),黄芪甲苷干预组其表达明显降低(P <0. 05),差异均具有统计学意义。电镜显示脓毒症造模24 h,NS组较Blank组心肌自噬小体明显增多,而黄芪甲苷组心肌自噬小体的形成较NS组明显减少。结论黄芪甲苷能够减少脓毒症大鼠心肌中Beclin1、p62和LC3基因及蛋白的表达,减少心肌自噬小体的形成。

Objective To explore the effects of astragaloside on the autophagy-related genes and proteins(Belin1,p62 and LC3)and the situation of myocardial autophagy in the rats with sepsis.Methods A total of 30 clean male Wistar rats were divided into a blank group,a normal saline group(venous injection on the tail)and an astragaloside group(venous injection on the tail),10 rats in each one according to the random number table.The colon ligation and perforation was adopted to prepare sepsis model.Using RT-PCR method,the mRNA levels of Beclin1,p62 and LC3 in myocardium were determined.Using Western blotting technique,the protein expressions of Beclin1,p62 and LC3 were determined in each group.Using transmission electron microscopy,the ultrastructure of myocardium and the formation of autophagosomes of acinar cells were observed.Results Compared with the blank group,the levels of the autophagy-related genes and proteins(Belin1,p62 and LC3)in myocardium were all increased obviously in the normal saline group( P <0.05)and the expressions were reduced obviously in the astragaloside group( P <0.05),indicating the significant differences between the two groups.The electromicroscopic results showed that after 24 h of sepsis modeling,the myocardial autophagosomes in the blank group were increased obviously as compared with the normal saline group and the autophagosomes in the astragaloside group were reduced obviously as compared with the normal saline group.Conclusion Astragaloside reduces the gene and protein expressions of Beclin1,p62 and LC3 in the myocardium of the rats with sepsis and reduces the formation of myocardial autophagosomes.