银杏叶提取物对α-葡萄糖苷酶的抑制作用及其降血糖作用机制

J4 ›› 2011, Vol. 37 ›› Issue (3): 427-432.

银杏叶提取物对α-葡萄糖苷酶的抑制作用及其降血糖作用机制

尚禹东¹, 张郑瑶², 丁云录³, 陈声武⁴, 赵广宏^*

（1.长春中医药大学药学院中药药理学教研室|吉林长春130117；2.吉林大学药学院生物化学与分子生物学教研室|吉林长春130021；3.吉林天药科技有限公司|吉林长春1300124.长春中医药大学附属医院实验研究中心|吉林长春130021）

收稿日期:2010-12-29 出版日期:2011-05-28 发布日期:2011-05-28
通讯作者: 陈声武 E-mail:E-mail:chenshengwu_1958@yahoo.com.cn
作者简介:尚禹东（1983-）|男|吉林省长春市人|药理学硕士|主要从事药效学研究。
基金资助:
国家科技部科技支撑计划项目资助课题（2007BA138B05）；吉林省科技厅科技发展计划项目资助课题（20071123）

Inhibitory effect of ginkgo biloba extract on alpha-glucosidase and its hypoglycemic mechanism

CHANG Yu-Dong¹, ZHANG Zheng-Yao², DING Yun-Lu³, CHEN Qing-Wu⁴, DIAO An-Hong^*

（1.Department of Pharmacology of Traditional Chinese Medicine,School of Pharmacy,Changchun University of Chinese Medicine,Changchun 130117,China;2.Department of Biochemistry and Molecular Biology,School of Pharmacy,Jilin University,Changchun 130021,China;3.Jilin Natural Pharmatech (China) Co.,Ltd.,Changchun 130012,China;4.Experimental Research Center,Affiliated Hospital,Changchun University of Chinese Medicine,Changchun 130021,China）

Received:2010-12-29 Online:2011-05-28 Published:2011-05-28

摘要/Abstract

摘要：

目的：通过体外药效学实验研究银杏叶提取物（GBE）对α-葡萄糖苷酶的抑制作用，探讨其降血糖的作用机制，为开发利用银杏叶资源提供实验依据。方法：提取大鼠小肠中的α-葡萄糖苷酶液，利用葡萄糖试剂盒测定酶活力；体外抑制实验分为正常对照组、阳性对照组及GBE高、中、低剂量组（10.0、5.0、2.5 g·L^-1)，对反应体系中的葡萄糖浓度进行测定，计算药物对蔗糖酶的抑制率；离体器官实验分为正常对照组、阴性对照组、阳性对照组和GBE高、中、低剂量组（10.0、5.0、2.5 g·L^-1)，对反应体系中的淀粉光密度值进行测定，计算药物对淀粉酶的抑制率；半数抑制率（IC₅₀）实验将GBE分为7个剂量组，分别计算药物对α-糖苷酶的抑制率及IC₅₀；抑制曲线实验分为正常对照组、阳性对照组及GBE组，计算反应速率，以底物浓度的倒数作为横坐标，以反应速率的倒数作为纵坐标，绘制抑制曲线。结果：大鼠小肠酶活力值为67.2活力单位。与正常对照组比较，GBE高、中、低剂量组蔗糖酶抑制率明显增加（P<0.001，P<0.001，P<0.01）；与正常对照组比较，GBE高剂量组大鼠小肠中淀粉酶抑制率明显增加（P<0.01）；GBE对蔗糖酶的IC₅₀值为0.758 6 g·L^-1，对淀粉酶的IC₅₀值为0.910 1 g·L^-1；GBE组趋势线与正常对照组斜率相近，且截距大于正常对照组趋势线。结论：GBE对α-糖苷酶具有良好的抑制作用，其作用机制为反竞争性抑制。

关键词: 银杏叶提取物；α-葡萄糖苷酶；体外抑制；降血糖

Abstract:

Abstract:Objective
To study the inhibitory effect of ginkgo biloba extract (GBE) on alpha-glucosidase by pharmacodynamic experiments in vitro,discuss the hypoglycemic mechanism,and provide experimental evidence for exploration and utilization of GBE. Methods The alpha-glucosidase was extracted from the small intestine of rats. The activity of α-glucosidase was determined by glucose kit. The inhibitory experiment in vitro was divided into normal control,positive control,and different doses of GBE(10.0,5.0,2.5 g·L^-1) groups. The concentration of glucose in the reaction system was detected and the inhibitory rate of drugs was calculated.The ex　vivo　 experiment was divided into normal control,negative control,positive control,and different doses of GBE(10.0,5.0,2.5 g·L^-1) group. The optical density value of starch in the reaction system was determined and the inhibitory rate of drugs was detected.The 50% inhibitory concentration (IC₅₀) experiment was divided into 7-dose groups. The inhibitory rate of drugs was calculated,and the IC₅₀ was calculated.The inhibitory curve experiment was divided into normal control,positive control,and GBE group and the reaction rate was calculate. The reciprocal of concentration of substrate was used as abscissa,and the reciprocal of reaction rate as ordinate,and the inhibitory curves were drawn. Results The activity of α-glucosidase in rat small intestine was 67.2 μmol·L-1·min^-1.The inhibitory experiment showed that high,moderate,low dose GBE inhibited the activity of alpha-glucosidase compared with normal control group(P<0.001,P<0.001,P<0.01);the ex vivo experiment results indicated that high dose GBE inhibited the hydrolytic effect of amylase from the segments of small intestine efficiently compared with normal control(P<0.01),the IC₅₀ of GBE on sucrase was 0.758 6 g·L^-1,and the IC₅₀ of GBE on amylase was 0.910 1 g·L^-1. Conclusion GBE has superior inhibition on α-glucosidase，and its mechanism is uncompetitive inhibition.

Key words: ginkgo biloba extract;α-glucosidase;extrasomatic inhibition;blood glucose reduction

中图分类号:

R965.2

尚禹东, 张郑瑶, 丁云录, 陈声武, 赵广宏. 银杏叶提取物对α-葡萄糖苷酶的抑制作用及其降血糖作用机制[J]. J4, 2011, 37(3): 427-432.

CHANG Yu-Dong, ZHANG Zheng-Yao, DING Yun-Lu, CHEN Qing-Wu, DIAO An-Hong. Inhibitory effect of ginkgo biloba extract on alpha-glucosidase and its hypoglycemic mechanism[J]. J4, 2011, 37(3): 427-432.