黄精多糖对高脂饲料诱发糖尿病小鼠糖代谢功能的影响

摘要

目的 建立小鼠高血糖模型,在此模型上考察黄精多糖(PSP)对于糖尿病小鼠体重、血糖、胰岛素、糖耐量、一氧化氮(NO)水平的影响.方法 小鼠按照体重随机建立正常对照组和模型组(Model组),Model组以高脂饲料喂养50周,造成糖尿病小鼠模型.造模成功后,从正常对照组中随机选取10只小鼠作为Control组,将Model组按照体重随机分为高脂饲料组(HFD组)和黄精多糖组(PSP组),每组各10只.PSP组用25 g/L黄精多糖水溶液、500 mg/kg剂量、每日1次灌胃给药8周,同时Control组和HFD组给予等量蒸馏水,通过血糖仪、胰岛素酶联免疫吸附测定(ELISA)试剂盒、Western-blot法检测各组血糖值、糖耐量、胰岛素水平、肝脏胰岛素受体(IRS-2)表达以及肝脏NO水平的影响.结果 Model组小鼠空腹血糖值、体重显著高于Control组,提示模型成功.PSP组小鼠与HFD组相比,空腹血糖值和胰岛素水平显著降低(P＜0.05),同时胰岛素受体IRS-2的表达量明显增加(P＜0.05),并在一定程度上降低了肝组织NO水平.结论 该糖尿病小鼠模型稳定,同时具有空腹高胰岛素血症的特点,对研究胰岛素抵抗的发病尤为适用.通过PSP对该模型的干预,显示PSP可以降低高血糖小鼠空腹血糖值、空腹胰岛素水平,同时提高胰岛素受体的表达,并对高血糖环境下的高氧化应激状态有一定的抑制作用.%Objective To establish mice model with hyperglycemia,and to investigate the effects of polygonatum polysaccharide (PSP) on the body weight,blood glucose,insulin,glucose tolerance and nitric oxide (NO) in this mice model.Methods Mice were randomly divided into normal coutrol group and model group by weight.Model group was given high-fat diet for 50 weeks,resulting in diabetic mice.Then 10 mice were selected as control group from normal control group,and the model group was randomly divided into high fat diet (HFD) group and PSP group by weight,with 10 mice in each group.PSP group was administrated with 25 g,/L PSP solution,500 mg/kg.once per day,for 8 weeks.Control group and HFD group were given the same volume of distilled water.Then the glucose levels,glucose toler ance,insulin levels,hepatic insulin receptor (IRS-2) expression and NO levels in the liver were investigated using blood glucose meter,insulin enzyme-linked immunosorbent assay (ELISA) kits or Western-blot assay.Results The fasting blood glucose levels and weights of model group were significantly higher than those of control group,suggesting that the model was successful.Compared with that of HFD group,the fasting glucose levels and insulin levels of PSP group were significantly reduced (P ＜ 0.05),and the IRS-2 expression was showed significantly increased (P ＜ 0.05) and NO was decreased to a certain degree by PSP intervention.Conclusion The diabetic mice model is stable,and it has the characteristics of fasting hyperinsulinemia,which is applicable for the study of the incidence of insulin resistance.PSP intervention can decrease the fasting blood glucose level,fasting insulin level,increase insulin receptor expression,and inhibit oxidative stress to a certain extent under high glucose environments in diabetic mice.