宁夏栽培甘草的黄酮提取物降糖作用实验研究

Studies on Hypoglycemic Effect of Flavonoids from the Cultivated Licorice in Mice

目的观察宁夏地区栽培甘草(Glycyrrhiza uralensis Fisch.)中获得的甘草黄酮提取物(licorice fla-vonoids,LF)对C57BL/6J小鼠为研究对象的2型糖尿病(T2DM)模型的降血糖作用及对正常BALB/c小鼠餐后血糖的调节作用。方法采用高脂高糖饮食喂养4周后联合注射链脲佐菌素(streptozotocin,STZ,100～125mg.kg-1,ip)制备C57BL/6J小鼠2型糖尿病模型,2周后实施300mg.kg-1和100mg.kg-1剂量的LF灌胃,干预5周后,测定空腹血糖值、糖耐量变化值,以及血清超氧化物歧化酶(SOD)、丙二醛(MDA)和谷胱甘肽过氧化物酶(GSH-PX)的变化。采用糖耐量实验观察LF对正常BALB/c小鼠实施蔗糖负荷(sucroseload)糖耐量的影响。结果 LF能够降低2型糖尿病C57BL/6J小鼠的空腹血糖值;升高血清SOD和GSH-PX水平的同时,降低血清MDA含量。LF对2型糖尿病C57BL/6J小鼠的糖耐量异常现象改善不明显。LF对于正常BALB/c小鼠实施蔗糖负荷后血糖峰值具有抑制作用。结论宁夏地区栽培甘草中获得的甘草黄酮提取物具有降低实验性2型糖尿病小鼠空腹血糖的作用,并具有调节正常动物餐后血糖的作用。

Objective To investigate the hypoglycemic effect of licorice flavonoids(LF) from cultivated licorice(Glycyrrhiza uralensis Fisch.) on type II Diabetes Mellitus in C57BL/6J mice,and evaluate the postprandial glucose level in normal BALB/c mice by the LF oral administration.Methods Mice model of type II diabetes mellitus(DM) was eastablished with long-term high fat and sugar diet(4week) and intraperitoneal injection of low-dose streptozotocin(STZ,100~125mg·kg-1).After implementation of the 300mg·kg-1 and 100mg·kg-1 doses of LF intragastrically adminstration over 40 days,the fasting blood glucose(FBG),2-hour post-prandial blood glucose(2 h PBG) contents were detected to evaluate the glycemic control,and serum superoxide dismutase(SOD),malondialdehyde(MDA),glutathione peroxidase(GSH-PX) were be analyzed at the end of the test.The oral glucose tolerance test(OGTT) was employed to study the effect of the LF on PBG contents by 2.0g·kg-1 dosage sucrose load.Results LF can lower FGB and increase the serum levels of SOD and GSH-PX,while reducing serum MDA level.LF did no obvious improvement on PBG to the type II Diabetes Mellitus in C57BL/6J mice,but,for the normal BALB/c mice,LF can low down the peak serum glucose level in OGTT.Conclusion Ningxia cultivated licorice flavonoids can produce the hypoglycemic effect on the type II Diabetes Mellitus in C57BL/6J mice,and modulate the PBG in nomal mice.