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

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(P0.05),对TC和LDL-C含量有极显著的降低作用(P0.01),对TG含量有显著降低作用(P0.05),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。

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

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 type 2 diabetic rats. Methods: A rat model of type 2 diabetes mellitus (T2DM) was constructed by feeding SD rats a high-fat diet and intraperitoneal injection of streptozocin into them at a dose of 40 mg/kg. The model rats were randomly divided into model control group (MC), positive control group (PC) (metformin at 150 mg/(kg·d)), DTP group (400 mg/(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.