麦冬皂苷D对大鼠心肌细胞凋亡及caspase通路的影响

Effects of Ophiopogon D on Cardiomyocyte Apoptosis and Caspase Pathway in Rats

目的:观察麦冬皂苷D对糖尿病(DM)大鼠心功能、心肌细胞凋亡的影响并探讨其机制。方法:将90只大鼠随机分为空白对照组、DM模型组、麦冬皂苷D低(10 mg·kg^(-1))、中(20 mg·kg^(-1))、高(40 mg·kg^(-1))剂量组、阳性对照(二甲双胍,160 mg·kg^(-1))组,每组15只。除空白对照组外,其余各组均采用腹腔注射链脲佐菌素复制DM模型。造模成功后,分别灌胃给药,空白对照组和DM模型组给予等量生理盐水,qd,持续4周。给药结束后,采用多普勒彩色超声评估各组大鼠心脏功能;苏木素-伊红(HE)染色观察心肌组织形态结构;激光共聚焦显微镜检测心肌细胞凋亡情况;蛋白免疫印迹分析caspase 3通路及其上游相关蛋白表达情况。结果:与空白对照组比较,DM模型大鼠心功能下降、心肌组织现病理损伤、细胞凋亡率升高,差异有统计学意义(P<0.05); Bax和cleaved-caspase 3蛋白在心肌组织表达上调(P<0.05),Bcl-2、p-Akt和p-GSK-3β蛋白在心肌组织表达下调(P<0.05)。与DM模型大鼠比较,麦冬皂苷D各剂量组大鼠心功能增强、心肌组织病理损伤程度减轻、细胞凋亡率降低(P<0.05); Bax和cleaved-caspase 3蛋白在心肌组织表达下调(P<0.05),Bcl-2、p-Akt和p-GSK-3β蛋白在心肌组织表达上调(P<0.05)。麦冬皂苷D低、中剂量组的各指标水平与阳性对照组比较差异有统计学意义(P<0.05)。结论:麦冬皂苷D可能通过调节Akt/GSK-3β抑制caspase 3通路,减轻糖尿病大鼠心肌损伤。

Objective: To observe the effects of ophiopogon D on cardiac function and cardiomyocyte apoptosis in diabetic (DM)rats and to explore its mechanism. Methods: Totally 90 rats were randomly divided into the blank control group,DM model group,ophiopogon D low (10 mg·kg-1),medium (20 mg·kg-1),and high (40 mg·kg-1) dose groups,the positive control group (metformin,160 mg·kg-1),and 15 rats in each group. Except for the blank control group,the DM model was replicated by intraperitoneal injection of streptozotocin. After the successful modeling,the rats in each group were given corresponding drug,and the blank control group and DM model group were given the same amount of saline,once daily for 4 weeks. After the administration,Doppler echocardiography was used to evaluate the cardiac function of rats in each group,hematoxylin eosin (HE) staining was used to observe the morphologic structure of myocardial tissue,myocardial apoptosis was detected by a laser confocal microscope,and Western blot was used to analyze the caspase 3 pathway and its upstream related protein expression. Results: Compared with that in the blank control group,the heart function of DM rats decreased,the myocardial tissues showed pathological injury,and the rate of apoptosis increased with statistically significant difference (P<0.05);the expressions of Bax and cleaved-caspase 3 protein were up-regulated in myocardial tissue (P<0.05);the expressions of Bcl-2,p-Akt and p-GSK-3β protein were down-regulated in myocardial tissue (P< 0.05). Compared with that in DM model rats,the heart function of rats in Ophiopogon D groups increased,myocardial tissue pathological injury degree decreased,and the rate of apoptosis decreased (P<0.05);the expressions of Bax and cleaved-caspase 3 in myocardial tissue were downregulated (P<0.05),the expressions of Bcl-2,p-Akt and p-GSK-3 beta protein were up-regulated in myocardial tissue (P < 0.05).Compared with the positive group,there were significant differences in ophiopogon D low and medium dose groups (P<0.05). Conclusion: Ophiopogonin D may alleviate myocardial injury in diabetic rats by regulating Akt/GSK-3β and inhibiting caspase 3 pathway.