摘要
目的探讨黄芪多糖(APS)对高脂加链脲佐菌素(streptozotocin,STZ)诱导的糖尿病大鼠心肌的保护作用及其可能的作用机制,为进一步研究APS对糖尿病治疗的作用提供理论依据。方法雄性SPF级SD大鼠40只,随机分为两组:高脂组(n=24)和普通组(n=16)。高脂组给予高脂饲料,普通组给予普通饲料。于饲养第8周末对高脂组动物行尾静脉注射STZ 25 mg/kg,1周后取高脂组中造模成功的16只SD大鼠再随机分为两组:糖尿病组(DM组,n=8),糖尿病+APS治疗组(DA组,n=8)。普通组也随机分为两组:正常组(C组,n=8),正常+APS对照组(CA组,n=8)。各组SD大鼠不限饮食和饮水。DM组和DA组继续给予高脂饲料。CA组和DA组同时灌胃给予APS(700 mg/kg·d-1)治疗,持续8周。定期检测动物体重、心脏指数(心重/体重)、空腹血糖(FBG)、血浆游离脂肪酸(FFA)、B型脑钠肽(BNP)、心肌肌钙蛋白I(cTnI),计算胰岛素抵抗指数(HOMA-IR),治疗第8周末处死动物,取心室肌组织,做心肌组织形态学观察,用TUNEL法检测心肌细胞凋亡情况。结果 DM组大鼠出现多饮多食多尿、体重减轻、高血糖、FFA增高、高胰岛素抵抗等2型糖尿病特征,并且出现心肌细胞肥大、凋亡、间质纤维化等表现,DA组上述改变均得到明显改善。结论 APS可以显著改善2型糖尿病大鼠胰岛素抵抗,主要表现为降低血糖、IRI,并能减轻糖尿病大鼠心肌损伤,这可能与抑制BNP表达、降低心肌细胞凋亡有关。
Objective To investigate the protective effects of Astragalus polysaccharide （APS） on the myocardium of experimental diabetic rats which was induced by high fat diet and STZ, and explore the effect of APS on diabetes mellitus. Methods Male SD rats （SPF） were ran- domly divided into four groups： Control group（C,n=8）, 4,PS control group（CA,n=8）, which were fed with normal food;Diabetes mellitus group （DM,n=8） and APS treated group （DA,n =8） which were established by high fat diet and STZ injection with small dosage （25 mg/kg）. Group DA and CA were treated with APS （700 mg/kg · d-1） for 8 weeks. Blood glucose, weight,FFA, BNP,cTnl and insulin resistance index（IRI） were periodically tested. At the end of 8-week treatment with APS,complete serial sections of left ventricle were cut and stained with HE, then were observed under light microscope, Apoptotic index（AI） of rat cardiac myocytes was examined by TUNEL. Results After being treated with APS for 8 weeks,the index of FBG, FFA,IRI in group DA markedly decreased compared with those of group DM, and the weight loss improved. Microscopically,the heart in cardiomyopathy demonstrates hypertrophy, apopto- sis of myocardial fibers along with interstitial fibrosis. Conclusion Diabetic rats induced by high fat diet and STZ injection were characterized with hyperglycemia, impaired oral glucose tolerance. After treatment with APS for 8 weeks, there is a significant decreasing in blood glucose and IRI（P〈0.05）in diabetic rats. The potential mechanisms of APS on diabetic rats may involve the following： decreasing the level of FBG and IRI, attenuating cardiac injury, inhibiting the ex- pression of BNP, and decreasing myocardial cell apoptosis.
出处
《湖北民族学院学报（医学版）》
2012年第4期16-19,共4页
Journal of Hubei Minzu University(Medical Edition)
基金
恩施土家族苗族自治州科技局重点项目(201012)
关键词
糖尿病
黄芪多糖
心肌细胞凋亡
B型脑钠肽
diabetic rats
Astragalus polysaccharide
myocardial cell apoptosis
BNP
