摘要
目的研究大豆多肽对四氧嘧啶(AXN)糖尿病(DM)模型大鼠的降血糖作用及对AXN损伤大鼠胰岛细胞的保护作用。方法用AXN建立大鼠DM模型,分别用500、250mg/kg体质量大豆多肽连续灌胃2周后,观察其对空腹血糖、糖耐量的影响。观察胰腺超微结构变化,分离并培养大鼠胰岛细胞并观察大豆多肽对AXN损伤的大鼠胰岛细胞的超氧化物歧化酶(SOD)活性、丙二醛(MDA)和一氧化氮(NO)含量的影响。结果大豆多肽高、低剂量均能降低DM模型大鼠血糖,其血糖绝对降低值(mmol/L)分别为10.65±5.33、8.84±4.66,显著高于DM模型组的4.16±4.48(P<0.05);改善DM大鼠的糖耐量,降低餐后血糖水平,与DM模型对照组比较,差异有统计学意义(P<0.05);但对餐后血糖的控制能力低于膳食纤维(P<0.05)。胰腺超微结构观察显示,大豆多肽组胰岛β细胞分泌颗粒内电子密度较高,颗粒外有较大的空隙,细胞质内线粒体、高尔基体水肿明显缓解。在培养的AXN损伤大鼠胰岛细胞中,大豆多肽的SOD水平(U/mL)较对照组显著升高(7.44±3.59、29.48±2.40),MDA和NO水平(μmol/L)降低,分别为5.59±0.88、2.39±0.15和81.38±3.79、61.85±1.84(P<0.05);且随着大豆多肽浓度的增加,其对AXN损伤的大鼠胰岛细胞的保护作用明显增强(P<0.05)。结论大豆多肽可明显降低AXN DM大鼠血糖,改善糖耐量,并对AXN损伤的大鼠胰岛细胞有保护作用。
Objective To study soybean polypeptide＇s hypoglycemic effect on the alloxan （AXN） diabetes mellitus （DM） model rats and protective effect on the alloxan-induced destruction of isolated rat pancreatic islets cells cultured in vitro. Methods The model of AXN DM was constructed in rats, which were then given soybean polypeptide of 500 and 250 mg/kgbw by gavage for two weeks. We observed the effects of soybean polypeptide on fasting serum sugar and glucose tolerance as well as ultra-structural changes of the pancreas. Isolated pancreatic islets cells from SD rats were cultured in vitro; the activity of superoxide dismutase （SOD）, the contents of malondialdehyde （MDA） and nitric oxide （NO） in rat pancreatic islets cells injured by AXN were measured. Results The high and low dose of soybean polypeptide significantly reduced the blood sugar level of DM model rats, improved glucose tolerance in DM rats, and reduced the postprandial blood glucose level. The difference between the model control group and soybean polypeptide group was significant （P〈0.05）. However, the control over postprandial blood glucose was significantly lower than that over dietary fiber （P〈 0.05）. Observation of pancreas ultra-microstructure showed increased electron density within the secretory granule in pancreatic β cells, a larger gap outside the secretory granule, and obviously relieved edema in mitochondria and golgi apparatus in the cytoplasm in high dose of soybean polypeptide. Soybean polypeptide could significantly increase SOD level from （7.44±3.59）U/mL to （29.48±2.40）U/mL in pancreatic islets cells from AXN-injured rats, and decreased MDA and NO contents from （5.59±0.88）nmol/L and （81.38±3.79）μmol/L to （2.39±0.15） nmol/L and （61.85± l. 84） ~tmol/L, respectively （P〈0.05）. With the increase of soybean polypeptide concentration, the protective effect was significantly increased in isolated pancreatic islets cells （P〈 0. 05）. Conclusion Soybean polypeptide can significantly reduce blood glucose and improve glucose tolerance in alloxan diabetic model rats and protect isolated pancreatic islets cells.
出处
《西安交通大学学报（医学版）》
CAS
CSCD
北大核心
2014年第2期191-195,共5页
Journal of Xi’an Jiaotong University（Medical Sciences）
基金
国家自然科学基金资助项目(No.81273051)~~
