【作者】 陈建国； 来伟旗； 江月仙； 梅松； 刘冬英； 傅颖； 陈日萍；

【Author】 Chen Jian-guo Lai Wei-qi Jiang Yue-xian Mei Song Liu Dong-ying Fu Ying Chen Ri-ping (Zhejiang Academy of Medical Sciences,Hangzhou 310013)

【机构】 浙江省医学科学院；

【摘要】 目的通过茶多糖对四氧嘧啶糖尿病小鼠糖代谢、组织形态学及胰岛β细胞超微结构的影响研究,探讨茶多糖调节血糖的作用机理。方法将四氧嘧啶糖尿病小鼠随机分成4组,每天分别灌胃给予蒸馏水、茶多糖0.25、0.50、1.00g/kg体重,连续5周,每周称重一次。在实验2周末、4周末各测空腹血糖一次。实验末期进行糖耐量实验;取股动脉血测血清胰岛素含量;取适量肝脏测肝糖元含量;制成10%肝匀浆测肝匀浆蛋白含量、己糖激酶(HK)、丙酮酸激酶(PK)活力;留取肝脏、胰腺、肾脏和脾脏做病理组织学检查;每组随机取5只小鼠胰腺做超薄切片、电镜观察。结果茶多糖能明显缓解糖尿病小鼠症状;三个剂量组小鼠空腹血糖值均明显降低(P<0.05或P<0.001),糖耐量实验结果为阳性,并存在剂量-反应关系。随着茶多糖剂量的增高,小鼠血清胰岛素、肝糖元含量均明显增高,肝己糖激酶、肝丙酮酸激酶活力均明显增强,各项指标与对照组比较均有显著性差异,且存在一定的剂量-反应关系;小鼠肝细胞变性程度有所减轻;胰岛数量明显恢复、体积增大,胰岛细胞明显修复、再生,三个剂量组小鼠胰岛数量明显高于对照组(P<0.05或P<0.001);胰岛β细胞内质网、线粒体等结构的损伤得到明显修复,酶原颗粒明显增多,细胞分泌等功能明显改善和恢复。各组小鼠肾脏、脾脏均未见明显异常改变。结论四氧嘧啶糖尿病小鼠肝脏肿大,肝细胞明显肿胀、颗粒样变伴空泡样变性;胰岛结构破坏、数量明显减少、体积缩小,胰岛细胞明显减少;胰岛β细胞内质网、线粒体明显损伤,酶原颗粒明显减少,分泌功能明显减弱。茶多糖通过促进四氧嘧啶糖尿病小鼠胰岛β细胞修复、再生、功能改善和恢复的作用;促进小鼠肝细胞的修复和肝功能的改善;使胰岛修复和再生、胰岛素分泌增加,同时提高肝己糖激酶、肝丙酮酸激酶活力等综合作用,促使血糖进入肝细胞,使肝糖元合成增加,葡萄糖氧化分解加快,从而达到调节糖代谢,降低血糖,改善糖尿病症状的作用。更多还原

【Abstract】 Objective:Through the study of tea polysaccharides(TP) on glucose metabolism,histomorphology and pancreatic isletβ-cell in ultrastructure alloxan diabetic mice,to discuss the tea polysaccharides mechanism that regulates blood glucose.Methods The alloxan diabetic mice were randomly divided into 4 groups were orally given distilled water,TP 0.25,0.50,1.00g/kg body weight per day,for five weeks,weighing once a week.In Experiment 2 and 4 weekend,the fasting blood glucose was tested once.The glucose tolerance test was conducted in the end of experiments;Taking femoral artery blood to measure the blood serum insulin content,taking appropriate liver tissue to measure the liver glycogen content;Some liver tissues were made of 10%liver homogenate measuring liver homogenate protein content,hexokinase(HK),pyruvate kinase(PK) vitality;taking liver,pancreas,kidney and spleen tissue do histopathological examination;each group was randomly chosen five mice to do ultra-thin slices of mouse pancreas and electron microscope observation.Results TP could significantly alleviate the symptoms of diabetic mice;the fasting blood glucose values of three dose groups mice were significantly decreased(P<0.05 or P<0.001),glucose tolerance test results are positive,with a dose-response relationship.The degree of liver cell degeneration in mice was alleviated;the number of pancreatic islets obviously restored,volume increased,the number of pancreatic islets in three-dose groups were significantly higher than the control group(P<0.05 or P<0.001);pancreatic isletsβ-cell endoplasmic reticulum,mitochondria structural damage was clearly restored,zymogen granules markedly increased,the secretion functions of cells were markedly improved and recovered.Kidneys and spleens of each group mice were no apparent abnormally altered.Conclusion The liver became hepatomegaly,liver cells apparent became swelling,granular degeneration with vacuolar degeneration;islet structural were damaged,the number significantly reduced,the volume deflated;pancreatic isletβ-cell endoplasmic reticulum,mitochondria were obviously damaged,zymogen particles and secretion function were decreased significantly in alloxan diabetic mice.Through promoting alloxan diabetic mice pancreatic isletβ-cell to repair,regeneration,functional improvement and restoration;promoting liver cells to repair and improving liver function;making pancreatic islet be repaired and regenerated,insulin secretion increased,while improving liver hexokinase,liver pyruvate kinase vitality and otherwise integrated role to promote blood glucose to enter the liver cells,so that glycogen synthesis,glucose oxidation and decomposition were accelerated,TP can achieve the glucose metabolism regulation and blood sugar reducing,and improve the diabetes symptoms.更多还原