探討甘草次酸促進HepG2細胞葡萄糖吸收之分子機制

Molecular mechanism for the glucose uptake promote activity of Glycyrrhetic acid in HepG2 cell

徐敏祐(Min-Yu Hsu)

指導教授 ： 張格東 ； 黃卓治

國立屏東科技大學/農學院/生物科技研究所/碩士(2012年)

https://doi.org/10.6346/NPUST.2012.00004

摘要

甘草次酸(Glycyrrhetic acid, GA)是一種三萜類化合物，具抗發炎及清除自由基之能力。本研究探討GA對降血糖作用之分子機制。HepG2細胞經GA處理24小時後，做細胞毒性測試，發現在高濃度(100μM)作用下，不會對細胞造成傷害。以葡萄糖螢光類似物2-NBDG(2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-d-glucose)測試HepG2細胞對葡萄糖之吸收作用，發現甘草次酸50μΜ及胰島素200nM均可刺激HepG2對葡萄糖的吸收能力，以西方墨點法分析，發現GA與胰島素均可增加HepG2細胞中葡萄糖轉運蛋白4 (GLUT4)之表現，再以螢光共軛焦顯微鏡觀察分析，發現兩者均可促進經TNF-α處理HepG2細胞之GLUT4 (glucose transporter 4)由胞內轉位至細胞膜。本研究推測甘草次酸可改善胰島素阻抗及HepG2細胞之葡萄糖之吸收。

關鍵字

甘草次酸 ； 葡萄糖轉運蛋白4 ； 胰島素 ； 2-NBDG

並列摘要

Licorice root is a traditional herbal remedy that has been used for the treatment of various pathologic conditions. The purpose of this study is to further explore the molecular mechanisms and hypoglycemic activities of 18β-glycyrrhetinic acid (GA). HepG2 cells were treated with 100μM GA for 24 hours for cell toxicity test. The results showed HepG2 cells remain the same to cytotoxicity test with GA. Furthermore, 2-[N-(7-nitrobenz-2-oxa-1, 3-diazol-4-yl)-amino]-2-deoxy-d-glucose (2-NBDG), a fluorescent glucose derivative was used to mimic the glucose uptake of HepG2 cells. We found that glucose transport 4 induced glucose uptake in HepG2 cells. In this study, 50μM GA and 200nM insulin were used to translocate GLUT4 to cell membrane. By Western blot experiment, GLUT4 was detected the amount of protein. The amount of GLUT4 varies when GA or insulin is with different concentration. By fluorescent microscope, 2-NBDG the absorbtion and the translocation of GLUT4 increased while the concentration of GA or insulin increases. GA, in this study, can improve the insulin resistance and glucose uptake of HepG2 cells treated by tumor necrosis factor-alpha (TNF-α).

並列關鍵字

Glycyrrhetic acid ； GLUT4 ； insulin ； 2-NBDG

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