纳米硒对实验性糖尿病小鼠心肌的保护作用及其可能的机制  

Protective effect and the possible mechanism of Nano-Se on myocardium of experimental diabetes mice

作　　者：陈鸿武[1] 马礼坤[1] 余华[1] 冯克福[1] 

机构地区：[1]安徽医科大学附属安徽省立医院心内科,安徽合肥230001

出　　处：《中国病理生理杂志》2008年第5期878-882,共5页Chinese Journal of Pathophysiology

摘　　要：目的:观察纳米硒对实验性糖尿病小鼠心肌的保护作用。方法:选取60只健康雄性昆明种小鼠,随机抽取10只小鼠作为正常对照组,其余50只小鼠禁食24h后,左下腹腔注射链脲佐菌素(streptozotocin,STZ)50mg/kgBW连续5d,7d后尾静脉取血测血糖,随机选择血糖值>16.65mmol/L的40只小鼠分为4组,分别是阳性对照组、低剂量(25μg/kg)纳米硒组、中剂量(50μg/kg)纳米硒组、高剂量(100μg/kg)纳米硒组。各组小鼠分别每天以0.2mL溶液灌胃补充生理盐水及相应剂量的纳米硒。每周称体重1次,各组剂量根据体重做相应调整。8周后摘除眼球放血处死小鼠,迅速取出心脏,取左心室部分心肌,制成10%心肌匀浆,测定SOD、GSH-Px活力及MDA含量;剩下心肌采用原位缺口末端标记法(TUNEL)检测心肌细胞凋亡,细胞免疫组织化学检测Bcl-2、Bax蛋白的表达。结果:与正常对照组比较,阳性对照组心肌SOD、GSH-Px活性降低,MDA水平升高,细胞凋亡率明显增加,Bcl-2表达下降,Bax蛋白表达增强;与阳性对照组比较,低、中剂量纳米硒组心肌SOD、GSH-Px活性升高,MDA水平降低,细胞凋亡率下降,Bcl-2蛋白表达增强,Bax蛋白表达下降;而高剂量纳米硒组心肌SOD、GSH-Px活性较中剂量钠米硒组有明显的下降,相应地MDA明显上升,细胞凋亡率明显增加,Bcl-2蛋白表达下降,Bax蛋白表达增强,与阳性对照组比较SOD、GSH-Px活性、MDA含量及心肌细胞凋亡率无明显差异。结论:给糖尿病小鼠补充一定剂量的纳米硒可以保护心肌,其机制可能与抗氧化、调节血糖及增强Bcl-2表达有关。AIM ： To observe the protective effect of Nano - Se on myocardium of experimental diabetes mice.METHODS ： Sixty healthy male KM mice were chosen, ten of which were selected randomly as the normal control group. After fasted for 24 h, the rest 50 mice were injected with streptozotocin （ STZ, 50 mg/kg） intraperitoneally for 5 d. At 7th d, the blood - sugar was measured from vena caudalis, 40 mice, of which blood - sugar exceeded 16.65mmol/L, were selected and randomized into 4 groups： the positive control group, low dose （25μg/kg） Nano - Se group, mid dose （50μg/kg） Nano-Se group, high dose （50μg/kg） Nano-Se group. All mice were given intragastric administration of 0.2 mL normal saline and corresponding dose of Nano - Se. The body weights were measured every week, and the dose of which was adjusted according to the change of the body weights. 8 weeks later, the mice were killed and cardiac muscle of the left ventricle was taken. The myocardium was prepared to 10% homogenate for measuring SOD, GSH - Px activity and MDA content. The myocardial cell apoptosis was measured by TUNEL. The expressions of Bcl -2 and Bax proteins were determined by immunohistochemistry. RESULTS ： Compared to normal group, the SOD and GSH - Px activities in positive control group decreased, MDA level increased, the rate of myocardial cell apoptosis increased significantly, Bcl - 2 protein expression deceased and Bax protein expression increased. Compared to positive control group, the SOD and GSH -Px activities in low and mid dose Nano - Se groups expression increased, MDA level decreased, myocardial cell apoptosis rate decreased, Bcl - 2 protein expression increased and Bax protein expression decreased. Moreover, the SOD and GSH - Px activities in high dose Nano - Se group decreased obviously compared to those in mid dose Nano - Se group. MDA level and myocardial cell apoptosis rate increased, Bcl -2 protein expression decreased and Bax protein expression increased, no significant difference in SOD, GSH - Px activ

关 键 词：纳米硒 糖尿病小鼠 心肌 细胞凋亡 蛋白质BCL-2 蛋白质BAX 

分 类 号：R363[医药卫生—病理学]