杜仲叶黄酮对糖尿病大鼠的血糖控制及对胰岛细胞的保护作用

目的:探讨杜仲叶黄酮对糖尿病大鼠血糖控制及对胰岛细胞的保护作用。方法:链脲佐菌素复制糖尿病大鼠模型,模型大鼠分为4组,即模型组、阳性药物组(格列本脲,10 mg·kg-1)、杜仲叶黄酮(2.5,5.0 g·kg-1)组,并设立正常组。ig给药,每日1次,连续28 d.取血测定大鼠空腹血糖(FBG),游离胰岛素(FINS)水平,并行口服葡萄糖耐量试验(OGTT);部分胰组织制备组织匀浆后测定超氧化物歧化酶(SOD),谷胱甘肽过氧化物酶(GSH-Px)及丙二醛(MDA)的含量;部分胰胰腺组织制作病理切片及HE染色,镜下观察胰岛形态及细胞数。结果:与正常组比较,模型组大鼠的FBG显著升高,FINS下降,糖耐量降低,胰腺组织中的SOD及GSH-Px水平降低,MDA水平升高,病理切片显示胰岛明显发生萎缩(P0.01);与模型组比较,杜仲叶黄酮能明显降低糖尿病大鼠胰腺组织中MDA水平、提高SOD及GSH-Px水平,并能降低大鼠的FBG,改善糖耐量,提高FINS水平(P0.01,P0.05),病理切片显示大鼠的胰岛面积增加、细胞数明显增多(P0.01,P0.05)。结论:杜仲叶黄酮可明显降低糖尿病大鼠的血糖,改善糖耐量,增加FINS水平,对胰岛细胞具有保护作用,推测降低氧化应激反应是其机制之一。

Effect of Eucommla ulmoides Leaves Flavonoids on Blood Glucose Control and Protection of Islet Cells in Diabetic Rats

Objective: To explore effect of Eucommla ulmoides leaves flavonoids on blood glucose control and the protection of islet cells in diabetic rats. Method: Streptozocin was used to copy diabetic rats model,modeling rats were divided into four groups, model group, positive drug group(glyburide, 10 mg·kg^-1),E.ulmoides leaves flavonoids groups (2.5,5.0 g·kg^-1), the normal group was setup. After 28 days fasting blood glucose (FBG) was collected,serum free insulin (FINS)level and oral glucose tolerance test were carried out. Superoxide dismutase (SOD),glutathione peroxidase (GSH-Px)and malondialdehyde(MDA)content of pancreas homogenate was assayed. Hematoxylin and eosin (HE) staining was used to the microscopic observation islet morphology and cell number. Result: Compared with normal group,the significant increase of FBG and MDA,FINS falling and reduced glucose tolerance,the SOD and GSH-Px levels in model group rats were observed. Pathological islet apparently showed atrophy(P<0.01). Compared with model group, E.ulmoides leaves flavonoids could obviously decrease the MDA level,raise the level of SOD and GSH-Px,reduce FBG,improve glucose tolerance and the level of FINS(P<0.01, P<0.05). Pathological section showed that the rat islet was increased,the number of cells was increased obviously(P<0.01,P<0.05). Conclusion: E.ulmoides leaves flavonoids can obviously reduce the blood sugar of diabetic rats,improve the glucose tolerance,and increase the level of FINS,has the protection of islet cell function,antioxidative stress reaction is one of its mechanisms.