黄芪多糖对高脂血症大鼠糖脂代谢及胰腺组织病理改变的影响

Effect of astragalus polysaccharides on glucose and lipid metabolism and pathological changes of pancreas in rats with hyperlipidemia

目的探讨黄芪多糖(APS)对高脂血症大鼠糖脂代谢及胰腺组织胰岛和腺泡细胞的影响。方法SD大鼠随机分为正常组、模型组、APS组。高脂血症大鼠模型通过高脂饮食饲养8周建立,APS组灌胃给予APS 700 mg/(kg·d)。8周后处死大鼠,采集血清标本,测定血糖、三酰甘油(TG)、总胆固醇(TC)、高密度脂蛋白胆固醇(HDL-C)和低密度脂蛋白胆固醇(LDL-C)的含量以及血清淀粉酶(AMS)活性。取肝脏组织匀浆测定TC、TG含量。取胰腺组织切片,HE染色,观察腺泡和胰岛细胞形态;免疫组化染色观察胰岛β细胞形态及数量变化。结果 APS能显著降低高脂血症模型大鼠血清中血糖、TC、TG和LDL-C含量以及AMS活性,增加HDL-C含量,也能显著降低高脂血症模型大鼠肝脏组织中的TC和TG含量;胰腺组织HE染色显示,高脂血症模型大鼠胰岛形态多不规则,边缘不整齐且破损有空隙,胰岛内血管管腔扩张,有炎性细胞浸润。腺泡细胞排列散乱,呈现弥漫性水肿,镜下可见炎性细胞浸润,少量散在出血坏死灶。APS组大鼠胰岛腺泡细胞病变都有不同程度改善;胰岛β细胞免疫组化染色显示,高脂血症模型大鼠胰岛β细胞数量显著减少,β细胞内胰岛素分泌颗粒减少甚至缺失,且分布不均匀。APS组大鼠胰岛β细胞数量及胰岛素分泌颗粒显著增加,且分布趋于集中。结论 APS能改善高脂血症大鼠糖脂代谢,保护其胰腺组织胰岛和腺泡细胞。

Objective To investigate the effect of astragalus polysaccharides（APS） on glucose and lipid metabolism and pancreatic islet and acinar cells in hyperlipidemic rats. Methods SD rats were randomly divided into the normal group,hyperlipidemia model group and APS group. The hyperlipidemic rat model was established by feeding on a high-fat diet for 8 weeks. After APS treatment at 700 mg/（kg·d） for 8 weeks,rats were sacrificed and serum samples were collected to determine the content of blood glucose,triglyceride（TG）,total cholesterol（TC）,high-density lipoprotein cholesterol（HDL-C）,low-density lipoprotein cholesterol（LDL-C） and the activity of serum amylase（AMS）. Liver tissue homogenate was taken to determine the content of TC and TG. Pancreatic tissues were taken and HE staining was performed to observe the morphology of acinar and islet cells. Immunohistochemical staining was performed to observe the morphology changes and number of pancreatic islet β cells. Results APS significantly reduced the levels of blood glucose,TC,TG and LDL-C and AMS activity,and increased HDL-C levels in hyperlipidemic rats.APS also reduced the contents of TG and TC in liver tissues. HE staining showed the irregular form,irregular edges and gaps of islets,expansion of blood vessel lumen in pancreatic islets,and infiltration of inflammatory cells in hyperlipidemic rats. Meantime,acinar cells were disorganized and appeared diffused edema,along with a small amount of scattered hemorrhagic necrosis. In APS group,the lesions of islet cells and acinar cells were improved in a certain degree. Immunohistochemical staining showed that the number of islet β cells was significantly reduced,and insulin secreting granules of β cells were significantly decreased and unevenly distributed in hyperlipidemic rats. After APS treatment,the number of pancreatic islet β cells and insulin secretory granules were significantly increased,and the distribution tends were concentrated. Conclusion APS can improve glucose and lipid metabolism in hyperlipidemic rats,and protect pancreatic islets and acinar cells.