佛手山药多糖对2型糖尿病大鼠糖脂代谢及氧化应激的影响

Effect of Dioscorea opposita Thunb. Polysaccharide on Glycolipid Metabolism and Oxidative Stress in Type 2 Diabetic Rats

目的:探讨佛手山药多糖对实验性2型糖尿病大鼠糖脂代谢及体内氧化应激的影响。方法:SD大鼠高脂饲料喂养,结合小剂量腹腔注射链脲佐菌素40 mg/kg建立糖尿病大鼠模型,成模大鼠随机分为模型组、阳性对照组(二甲双胍150 mg/(kg·d))和佛手山药多糖组(400 mg/(kg·d)),并设正常组。观察给药期间各组体质量及血糖变化,给药6周后摘眼球取血,检测甘油三酯(triacylglyceride,TG)、胆固醇(total cholesterol,TC)、低密度脂蛋白胆固醇(low density lipoprotein cholesterol,LDL-C)、高密度脂蛋白胆固醇(high density lipoprotein cholesterol,HDL-C)、丙二醛(malonaldehyde,MDA)、一氧化氮(NO)含量及超氧化物歧化酶(superoxide dismutase,SOD)、过氧化氢酶(catalase,CAT)、谷胱甘肽过氧化物酶(glutathione peroxidase,GSH-Px)活力,并解剖称取新鲜肝脏,测定肝糖原含量。结果:与模型组比较,佛手山药多糖能有效缓解糖尿病大鼠的症状,能明显降低实验性2型糖尿病大鼠空腹血糖水平(P<0.05),对TC和LDL-C含量有极显著的降低作用(P<0.01),对TG含量有显著降低作用(P<0.05),能显著增加SOD和CAT的活力,而对肝糖原,HDL-C、MDA、NO含量及GSH-Px的活力无显著影响。结论:佛手山药多糖对实验性2型糖尿病大鼠有降低血糖作用,对血脂代谢紊乱有一定的调节作用,其降糖和降脂的具体机制可能与提高机体SOD、CAT活性相关。

Objective:To investigate the effect of Dioscorea opposita Thunb.polysaccharide(DTP)extracted from the rhizomes of the‘Foshou’cultivar on glycolipid metabolism and oxidative stress in type2diabetic rats.Methods:A ratmodel of type2diabetes mellitus(T2DM)was constructed by feeding SD rats a high-fat diet and intraperitoneal injection of streptozocin into them at a dose of40mg/kg.The model rats were randomly divided into model control group(MC),positive control group(PC)(metformin at150mg/(kg·d)),DTP group(400mg/(kg·d)),and normal control group(NC).During an administration period of six weeks,the general condition of rats was observed.Body weight,hepatic glycogen,blood glucose,and triacylglyceride(TG),low density lipoprotein cholesterol(LDL-C),HDL-C,malonaldehyde(MDA),nitric oxide(NO)and the activties of superoxide dismutase(SOD),catalase(CAT),glutathione peroxidase(GSH-Px)in serum were tested.Results:Compared with the model group,DTP effetively lowered fasting blood glucose levels in rats with experimental T2DM,highly significantly reduced serum TC and LDL-C levels,significantly decreased serum TG levels,and significantly enhanced the activities of SOD and CAT,but it had no significant impacts on hepatic glycogen,serum HDL-C,MDA and NO levels or serum GSH-Px activity.Conclusion:DTP shows a significant hypoglycemic effect on T2DM rats,and can regulate lipid metabolic disorders and the underlying mechanism may be associated with the enhanced activities of CAT and SOD.