沙库巴曲缬沙坦对糖尿病大鼠心室肌细胞的作用机制研究  

Impacts and related mechanisms of sacubitril/valsartan on ventricular myocytes in diabetic rats

作　　者：刘莹 钱玲玲 张煜敏 鹿存玉 李库林 王如兴 Liu Ying;Qian Lingling;Zhang Yumin;Lu Cunyu;Li Kulin;Wang Ruxing(Department of Cardiology,Wuxi People′s Hospital Affiliated to Nanjing Medical University,Wuxi 214023,China;Department of Cardiology,Wuxi Ninth People′s Hospital,Wuxi 214062,China)

机构地区：[1]南京医科大学附属无锡人民医院心内科,无锡214023 [2]无锡市第九人民医院心内科,无锡214062

出　　处：《中华糖尿病杂志》2022年第6期603-611,共9页CHINESE JOURNAL OF DIABETES MELLITUS

基　　金：国家自然科学基金面上项目(81770331);无锡市双百后备拔尖人才(HBBJ-11)。

摘　　要：目的探讨沙库巴曲缬沙坦对糖尿病大鼠心室肌细胞的保护作用及相关机制。方法选取40只周龄为6~8周的雄性SD大鼠,通过腹腔注射链脲佐菌素建立1型糖尿病大鼠模型,将大鼠分为对照组、糖尿病(DM)组、缬沙坦(DM+Val)组(30 mg·kg^(-1)·d^(-1))及沙库巴曲缬沙坦(DM+Sac/Val)组(60 mg·kg^(-1)·d^(-1))。8周后采用超声心动图检测各组大鼠心功能指标,包括左心室射血分数(LVEF)和左心室短轴缩短率(LVFS),HE染色观察心室肌结构及细胞形态,脱氧核苷酸末端转移酶介导的脱氧尿三磷酸生物素缺口末端标记(TUNEL)染色观察大鼠心室肌细胞凋亡情况,PCR及Western blotting分别检测各组大鼠心室肌组织B淋巴细胞瘤因子相关X蛋白(Bax)、B淋巴细胞瘤-2(Bcl-2)、C/EBP同源蛋白(CHOP)及葡萄糖调节蛋白78(GRP 78)的mRNA及蛋白表达情况,采用免疫组织化学染色观察GRP 78的蛋白表达情况。采用独立样本t检验、单因素方差分析、Mann‐Whitney U或Kruskal-Wallis H检验进行组间比较。结果TUNEL染色结果显示,与对照组[(0.164±0.048)%]相比,DM组[(2.116±0.305)%]大鼠心室肌细胞凋亡增多;与DM组相比,DM+Val组[(1.121±0.097)%]和DM+Sac/Val组[(0.513±0.031)%]大鼠心室肌细胞凋亡均降低;DM+Sac/Val组较DM+Val组大鼠心室肌细胞凋亡率更低,差异均具有统计学意义(P<0.001)。与对照组相比,DM组大鼠心室肌组织促凋亡蛋白Bax的蛋白及mRNA表达量增加,抑凋亡蛋白Bcl-2的蛋白及mRNA表达量减少,且Bcl-2/Bax降低;与DM组相比,DM+Sac/Val组Bax的蛋白及mRNA表达量降低,蛋白Bcl-2的蛋白及mRNA表达量增加,差异均具有统计学意义(P<0.05)。与对照组相比,DM组大鼠心室肌组织内质网应激相关蛋白GRP 78及CHOP的蛋白及mRNA表达量均增加;与DM组相比,DM+Val组大鼠心室肌组织中CHOP蛋白表达量、GRP 78及CHOP mRNA的表达量均降低,DM+Sac/Val组GRP 78及CHOP的蛋白及mRNA表达量均降低,差异均具有统计学意�Objective To investigate the protective effects and mechanisms of sacubitril/valsartan on ventricular myocytes in diabetic rats.Methods Forty Sprague Dawley(SD)rats aged 6 to 8 weeks were used to establish type 1 diabetic model by intraperitoneal injection of streptozotocin.Rats were divided into control group,diabetes(DM)group,diabetes+valsartan(DM+Val)group(30 mg·kg^(-1)·d^(-1))and diabetes+sacubitril/valsartan(DM+Sac/Val)group(60 mg·kg^(-1)·d^(-1)).After 8 weeks,cardiac function indexes of rats in each group were measured by cardiac ultrasound:left ventricular ejection fractions(LVEF),left ventricular short axis shortening rate(LVFS).Hematoxylin-eosin(HE)staining was used to observe the structure and morphology of ventricular myocytes,and apoptosis was determined by terminal deoxynucleotidyl transferase-mediated deoxyuria triphosphase-biotin nick end labeling(TUNEL)staining.Protein and mRNA expression of B-cell lymphoma-2 associated X(Bax),B-cell lymphoma-2(Bcl-2),C/EBP homologous protein(CHOP)and glucose regulatory protein 78(GRP 78)of ventricular myocytes were tested by Western blotting and polymerase chain reaction(PCR),respectively.Immunohistochemical staining was used to observe the expression of GRP 78.Independent-sample t test,one-way analysis of variance(ANOVA),Mann-Whitney U or Kruskal-Wallis H test were used for comparison between groups.Results TUNEL staining showed that apoptosis rate of ventricular myocytes in DM group[(2.116±0.305)%]was increased compared with control group[(0.164±0.048)%].Compared with DM group,apoptosis rate of ventricular myocytes was decreased in DM+Val group[(1.121±0.097)%]and DM+Sac/Val group[(0.513±0.031)%].The apoptosis rate of ventricular myocytes in DM+Sac/Val group was lower than that in DM+Val group(all P<0.001).In comparison with control group,the protein and mRNA expression of pro-apoptotic protein Bax was increased in DM group,while the expression of anti-apoptotic protein Bcl-2 was decreased,and the Bcl-2/Bax ratio was significantly decreased.The protein a

关 键 词：糖尿病 沙库巴曲缬沙坦 内质网应激 心室肌细胞凋亡 

分 类 号：R587.1[医药卫生—内分泌]