黄芪提取物对结肠腺癌Caco-2细胞葡萄糖吸收的影响

Effect of Astragali Radix Extracts on Glucose Absorption in Colon Adenocarcinoma Caco-2 Cell

目的:探讨黄芪提取物对Caco-2细胞葡萄糖吸收的影响,并探讨其作用机制。方法:采用系统溶剂法提取黄芪各部位,以Caco-2细胞为研究对象,设立空白组和黄芪各提取部位组(乙醇、石油醚、乙酸乙酯、正丁醇4个部位组)。以荧光标记2-脱氧葡萄糖(2-NBDG)做为光学探针检测黄芪各提取部位对Caco-2细胞葡萄糖吸收能力的影响。筛选出黄芪中促进Caco-2细胞葡萄糖吸收的药效部位后,对这一药效部位有效作用浓度进行考察。采用蛋白免疫印迹法(Western blot)法测定Caco-2细胞钠依赖葡萄糖转运蛋白(SGLT1)和2型葡萄糖转运蛋白(GLUT2)蛋白表达。结果:黄芪正丁醇提取部位可以促进Caco-2细胞葡萄糖的吸收,与空白组比较,黄芪正丁醇提取部位100,150 mg·L-1组Caco-2细胞葡萄糖含量升高(P<0.05,P<0.01);且黄芪正丁醇部位可以上调Caco-2细胞GLUT2和SGLT1蛋白的表达(P<0.05,P<0.01)。结论:黄芪正丁醇萃取部位可以促进Caco-2细胞葡萄糖的吸收,这一作用机制可能与SGLT1和GLUT2蛋白的调节有关。

Objective： To investigate effects of Astragali Radix extracts on glucose absorption in Caco-2cell and its relevant regulation mechanism. Method： All extracts of Astragali Radix were extracted by using systematical solvent separation method. Except for the blank group,Caco-2 cells were treated with Astragali Radix extracts,and then divided into four extraction groups（ ethanol,petroleum ether,ethyl acetate,and n-butanol）.The glucose absorption was detected by using the fluorescent D-glucose analog,with 2-deoxyglucose（ 2-NBDG） as the probe indicator. After the efficient extracts for promoting glucose absorption in Caco-2 cell was extracted from Astragali Radix,its effective concentration was studied. The expression of sodium-dependent glucose transporter 1（ SGLT1） and glucose transporter 2（ GLUT2） were detected by Western blot. Result： Astragali Radix n-butanol extract could improve glucose absorption in Caco-2 cell. Compared with control group,Astragali Radix n-butanol extract 100,150 mg·L- 1group showed significant increase in glucose content in Caco-2 cells（ P〈0. 05,P〈0. 01）. N-butyl alcohol extracts of Astragali Radix could up-regulate GLUT2 and SGLT1 of Caco-2 cells（ P〈0. 05,P〈0. 01）. Conclusion： Astragali Radix n-butanol extract can promote the glucose absorption in Caco-2cells. Its mechanism of improving glucose absorption may be correlated with regulation of SGLT1 and GLUT2.