青稞多糖对糖尿病模型小鼠的降血糖作用及机制研究

Study on Hypoglycemic Effect of Hordeum vulgare Polysaccharide on Diabetes Mellitus Model Mice and Its Mechanism

目的:研究青稞多糖(HVP)对糖尿病模型小鼠的降血糖作用及机制。方法:对小鼠腹腔注射链脲佐菌素(120 mg/kg)以复制糖尿病模型。将造模成功的小鼠随机分为模型组、二甲双胍组(阳性对照,200 mg/kg)和HVP高、中、低剂量组(300、150、75mg/kg),另设空白对照组,每组10只。各给药组灌胃相应药物,空白对照组和模型组小鼠灌胃等量水,每天1次,连续30天。给药10、20、30天时测定小鼠的空腹血糖(FBG);末次FBG测定后,小鼠腹腔注射10%葡萄糖溶液(2 g/kg),于注射后30、120 min时测定糖耐受量(GTT)曲线下面积;测定小鼠血清中胰岛素水平和肝组织中超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、丙二醛(MDA)的含量;采用苏木精-伊红染色法观察小鼠胰腺组织病理学变化。结果:与空白对照组比较,模型组小鼠FBG、GTT曲线下面积和肝组织中MDA含量均显著升高或增加(P<0.01);血清中胰岛素水平和肝组织中SOD、GSH-Px含量均显著降低(P<0.01);胰腺组织损伤严重,形态不完整,有明显的空泡。与模型组比较,HVP高剂量组小鼠FBG、GTT曲线下面积和肝组织中MDA含量均显著降低或减少(P<0.05或P<0.01),血清中胰岛素含量和肝组织中SOD、GSH-Px含量均显著升高(P<0.05或P<0.01),HVP低、中剂量组上述指标部分改善,差异具有统计学意义(P<0.05或P<0.01);胰腺组织损伤有所减轻,形态较为完整,胰岛细胞排列紧密,空泡减少。结论:HVP可降低糖尿病模型小鼠的血糖水平,升高胰岛素水平并减轻胰腺组织损伤;该作用机制可能与其抗氧化作用有关。

OBJECTIVE:To study the hypoglycemic effect of Hordeum vulgare polysaccharide(HVP)on diabetes mellitus model mice and its mechanism.METHODS:The mice were given intraperitoneal injection of streptozotocin(120 mg/kg)to induce diabetes mellitus model.After modeling,the mice were randomly divided into model group,metformin group(positive control,200 mg/kg),HVP high-dose,medium-dose and low-dose groups(300,150 and 75 mg/kg),with 10 mice in each group.Blank control group was established additionally.Administration groups were given relevant medicine intragastrically;blank control group and model group were given constant volume of water intragastrically,once a day,for consecutive 30 days.The levels of fasting blood glucose(FBG)were determined after 10,20,30 days of administration.After last FBG test,mice were intraperitoneally injected with 10%glucose solution(2 g/kg),then the area under the glucose tolerance(GTT)curve was measured at 30 and 120 min after injection.The serum levels of insulin,the content of superoxide dismutase(SOD),glutathione peroxidase(GSH-Px),malondialdehyde(MDA)in liver tissue were detected.Pancreatic morphology of mice were detected by HE staining.RESULTS:Compared with blank control group,the FBG,area under GTT curve and MDA contnet in liver tissue were increased significantly in model group(P<0.01),while serum levels of insulin,SOD and GSH-Px contents in liver tissue were decreased significantly(P<0.01);the pancreatic tissue was seriously damaged with incomplete morphology and obvious vacuoles.Compared with model group,FBG,area under GTT curve,MDA content in liver tissue were decreased significantly in HVP high-dose group(P<0.05 or P<0.01),serum content of insulin,the content of SOD and GSH-Px in liver tissue were increased significantly(P<0.05 or P<0.01);above indexes of HVP low-dose and medium-dose groups were improved partially,with statistical significance(P<0.05 or P<0.01);the pancreatic tissue damage was alleviated,the morphology was relatively complete,the islet cells were closely arranged,and the vacuoles were reduced.CONLUSIONS:HVP can reduce the level of blood glucose in diabetic model mice,increase insulin level and relieve pancreatic injury.The mechanism may be related to its antioxidation.