【作者】 张丽英；

【导师】 吴绥生；

【作者基本信息】 吉林大学 ， 内科学， 2012， 硕士

【摘要】 DCM是糖尿病的主要慢性并发症之一，与糖尿病患者高发病率和死亡率密切相关。大量的研究结果表明，高血糖引起的氧化应激在DCM的众多发病机制中起重要作用，是DCM发生、发展的重要因素。而氧化应激通过调控细胞凋亡，促进心肌、血管损伤。目前人们对人参皂苷Re发挥心肌保护作用的认识，主要集中在抗缺血性心肌病的动物模型中，而对于糖尿病患者心肌是否也具有保护作用，目前还未见报道。本实验主要从人参皂苷Re对糖尿病大鼠心肌组织的抗氧化和抗细胞凋亡的作用入手，研究人参皂苷Re对糖尿病心肌病的心肌的保护作用。实验选用健康雄性Wistar大鼠50只，体重（160±20）g，随机分为四组，空白组（C组）10只，其余40只大鼠腹腔注射链脲佐菌素（STZ）35mg/kg制造糖尿病大鼠模型，以72h后随机血糖≥16.7mmol/L为造模成功，造模成功后将大鼠随机分为糖尿病模型组（DM组），人参皂苷Re组（Re组），吡格列酮组（P组），分别给予相应量的纯净水，人参皂苷Re25mg/（kg d），吡格列酮10mg/（kg d）灌胃，连续给药4周。4周后处死大鼠，分别检测血糖、血脂，血清和心肌组织中SOD活性和MDA含量以及心肌组织中Bcl-xl，caspase9表达，观察心肌结构改变。结果表明，Re组和P组均能够明显改善糖尿病大鼠多食、多饮、多尿症状，增加体重，改善大鼠生存质量，Re组和P组比较无统计学差异（P＞0.05）。与DM组比较，Re组和P组均能降低空腹血糖和血清总胆固醇，差异有统计学意义（P<0.01），但两组空腹血糖和血清总胆固醇水平较C组高（P<0.01），Re组和P组之间无统计学差异（P＞0.05）。与DM组比较，Re组和P组均能提高血清和心肌组织中SOD活性，降低MDA含量，差异有统计学意义（P<0.01或P<0.05），两组SOD活性较C组低，MDA含量较C组高（P<0.05），但Re组和P组之间无统计学差异（P＞0.05）。心肌组织病理学观察显示：与DM组比较，Re组和P组都能够减轻心肌组织损伤程度，降低心肌胶原纤维及毛细血管周围胶原纤维含量，减少心肌细胞间质炎细胞浸润和心肌坏死程度；心肌凋亡相关蛋白表达结果显示，与DM组比较，Re组和P组均能明显减少凋亡蛋白caspase-9的表达，提高抗凋亡蛋白Bcl-xl的表达，差异有统计学意义（P<0.01），但Re组和P组之间无统计学差异（P＞0.05）。人参皂苷Re能降低空腹血糖和血清总胆固醇；能显著提高血清和心肌组织中SOD活性，降低MDA含量；能改善心肌组织结构的损伤，减少心肌胶原纤维及毛细血管周围胶原纤维含量；能抑制caspase-9蛋白，提高Bcl-xl蛋白的表达，抑制心肌细胞凋亡，提高心肌细胞存活率，发挥心肌保护作用。更多还原

【Abstract】 Diabetic cardiomyopathy (DCM) is one of the major chroniccomplications of diabetes. It is closely related to the high morbidity andmortality of diabetic patients. Many studies show that, hyperglycemia inducedoxidative stress plays an important role in the pathogenesis of DCM. It is animportant factor in the progress of DCM. And oxidative stress promotes cardiacand vascular injury through the regulation of apoptosis. Until now, therecognization of ginsenoside Re on myocardial protection are mailyconcentrated in the animal model of ischemic cardiomyopathy. There have notbeen reported that whether ginsenoside Re has a protective effect in DCM. Inthis study, we will focus on the effect of ginsenoside Re on anti-oxidation andanti-apoptotic and show that ginsenoside Re has myocardial protective effectson diabetic cardiomyopathy in rats.50healthy male Wistar rats [(160±20) g] were prepared in the study. Therats were divided into four groups at random and control group (c group) had10rats. The rest40rats were made diabetic model be given streptozotocin(STZ)35mg/kg by intraperitoneal injection.72hours later, the rats whose bloodglucose was above16.7mmol/L three consecutive days were regarded as thesuccess of diabetes mellitus rat model. After the model was successful, the ratswere divided into diabetic model (DM group), ginsenoside Re group (Re group)and pioglitazone group (P group) at random and were given correspondingamount of pure water, ginsenoside Re25mg/(kg·d) and pioglitazone10mg/(kg·d) by intragastric administration. All four groups were four weeks byintragastric administration in a row. All rats were killed after4weeks. Glucoseand lipids were tested. The SOD activities and content of MDA in serum and cardiac tissue were tested respectively. The expression of Bcl-xl and caspase-9in cardiac tissue were detected. Observe the change of myocardial sructure.The results show that Re and P groups can significantly improve thesymptoms, such as polyphagia, polydipsia and polyuria, increase weight andimprove the quality of life of rats. But the weight of Re and P groups was nosignificant difference (P＞0.05). Compared with DM group, Re and P groupscan all lower the level of fasting blood glucose and serum total cholesterol andthe difference was significant (P＜0.01). But compared with C group, the levelof fasting blood glucose and serum total cholesterol were all higher (P＜0.01),and there is no significant difference between Re and P groups (P＞0.05).Compared with DM group, Re and P groups could increase the activity of SODand decrease the content of MDA in serum and myocardial tissue, and thedifference was significant (P＜0.05or P＜0.01). But compared with C group,the activity of SOD were lower and the content of MDA were higher(P＜0.05),and there is no significant difference between Re and P groups (P＞0.05).Histopathological examination shows that compared with DM group, Re and Pgroups could decrease myocaidial injury, reduce myocardial collagen fibers andcollagen fiber content around capillaries, and reduce the infiltration ofinflammatory cells in the interstitial myocardial cells and the size of necrosis.The expression of myocardial apoptosis related proteins show that comparedwith DM group, Re and P groups could significantly reduce the expression ofthe apoptotic protein caspase-9, and improve the expression of theanti-apoptotic protein Bcl-xl and the difference was significant (P＜0.01). Butthere is no significant difference between Re and P groups (P＞0.05).Ginsenoside Re can reduce the level of fasting blood glucose and serumtotal cholesterol, increase the activity of SOD and decrease the level of MDA inserum and cardiac tissue in rats. Ginsenoside Re can also improve the damage of cardiac tissue structure and reduce the content of myocardial collagen fibersand collagen fiber around capillaries. Ginsenoside Re can inhibitcardiomyocyte apoptosis and increase myocardial cell survival to protectmyocardial cells by reducing the expression of caspase-9protein, andimproving the expression of the Bcl-xl protein.更多还原