姜黄素对HepG2细胞增殖及Keap1、Nrf-2表达的影响

Effects of curcumin on HepG2 cell proliferation and expression of Keap1 and Nrf-2

目的探索姜黄素对肝癌HepG2细胞增殖及Keap1、Nrf-2表达的影响。方法姜黄素(10μmol/L、20μmol/L、40μmol/L)处理HepG2细胞,采用MTT法检测细胞增殖活力,Real-time PCR法检测Keap1 m RNA的表达,Western blotting法检测Keap1及Nrf-2蛋白的表达,荧光酶标仪检测细胞内活性氧(ROS)的变化。结果姜黄素可抑制HepG2细胞的增殖活性,中剂量组与低剂量组相比具有显著性差异(P<0.05),高剂量组与中剂量组之间差异不明显(P>0.05);姜黄素可促进Keap1 m RNA及蛋白的表达,表达量随着药物浓度上升呈升高趋势(P<0.05);姜黄素可抑制Nrf-2蛋白表达,且随着药物浓度的增加Nrf-2蛋白表达量降低(P<0.05);随着姜黄素浓度增加,HepG2细胞内ROS生成量升高(P<0.05)。结论姜黄素可以抑制HepG2细胞的增殖,其机制可能与促进Keap1表达,从而抑制Nrf-2核转位,致Nrf-2抗氧化功能弱化,ROS生成增加,促进了细胞凋亡有关。

Objective To explore the effects of curcumin on Hep G2 cell proliferation and the expression of Keap1 and Nrf-2.Methods Hep G2 cells were treated with curcumin（10 μmol/L,20 μmol/L and 40 μmol/L）.MTT method was adopted for detecting the cell proliferation activity,real-time PCR method was adopted for detecting the expression of Keap1 m RNA,Western blotting method was adopted for detecting the expression of Keap1 and Nrf-2 protein,and fluorescence microplate was adopted for detecting the changes in the intracellular reactive oxygen species（ROS）.Results Curcumin could inhibit the proliferation activity of Hep G2 cell;there was significant difference between the middle-dose group and low-dose group（P〈0.05）,but the difference between the high-dose group and the middle-dose group was not significant（P〈0.05）; curcumin could promote the expression of Keap1 m RNA and protein and the expression increased with the increase of drug concentration（P〈0.05）; curcumin could inhibit the expression of Nrf-2 protein and the expression decreased with the increase of drug concentration（P〈0.05）; the intracellular ROS of Hep G2 increased with the increase of curcumin concentration（P〈0.05）.Conclusion Curcumin could inhibit the proliferation of Hep G2.The mechanism may be correlated to the promotion of Keap1 expression,the inhibition of Nrf-2 nuclear translocation,the weakening of Nrf-2 antioxidant function,the increase of ROS and the acceleration of cell apoptosis.