白桦脂酸对HepG2细胞的诱导凋亡作用及其机制

The Inducing Apoptosis Effect of Betulinic Acid on HepG2 Cell Line and Its Possible Mechanism

为研究白桦脂酸对人的HepG2细胞的凋亡作用及其机制。采用不同质量浓度的白桦脂酸处理HepG2细胞,MTT法测定白桦脂酸对HepG2细胞增殖影响;流式细胞术Annexin V-FITC/PI双染法检测细胞凋亡,PI单染法检测细胞周期,罗丹明123检测线粒体膜电位。MTT分析表明,白桦脂酸可抑制HepG2细胞增殖并呈剂量依赖关系。白桦脂酸对HepG2细胞24,48,72 h的半抑制质量浓度IC_(50)分别为52,26,17.5μg/mL。流式细胞仪检测结果表明,用20,30,40μg/mL的白桦脂酸分别处理48 h,总凋亡率分别为49.82%,55.575%,57.46%。细胞周期结果表明,随着白桦脂酸质量浓度的增加,G1期的细胞比例下降,S期的细胞比例增加,说明出现S期的阻滞。用质量浓度分别为20,40,80μg/mL的白桦脂酸处理的各组线粒体膜电位分别为83.63,73.63,64.3,与对照组89.25相比,均明显降低,这表明白桦脂酸诱导细胞凋亡可能与线粒体途径有关。白桦脂酸可抑制肝癌HepG2细胞的增值,诱导HepG2细胞凋亡,这一机制可能与线粒体途径有关,通过将细胞阻滞在S期来实现。

This study was to explore the antitumor effect of betulinic acid on HepG2 cells and its possible mechanism.Treated HepG2 cells with different mass concentrations of betulinic acid and detected the influence on the proliferation of HepG2 cells with MTT assay.Apoptosis rate,cell cycle and mitochondrial membrane potential were detected by flow cytometry.Results:MTT assay showed that different mass concentrations of betulinic acid suppressed the proliferation of HepG2 cells in a dose and time dependent manner.The half inhibitory concentration ( IC50) of betulinic acid on HepG2 cells at 24,48,72 h were 52,26,17.5μg/mL,respectively.Flow cytometry results showed that with regard to the groups with 20,30,40μg/mL betulinic acid-treated for 48 h,total apoptosis rates were 49.82%,55.575%,57.46% separately.The cell cycle results showed that with the increasing mass concentration of betulinic acid,the proportion of cells in G1 phase decreased and the proportion of cells in S phase increased,indicating S-phase arrested.The mitochondrial membrane potential of the groups treated with 20,40 ,80μg/mL were 83.63,73.63,64.3,compared with 89.25 in the control group,significantly decreased,indicating that betulinic acid-induced apoptosis might be associated with mitochondria pathway.Conclusion :Betulinic acid could inhibit the appreciation of HepG2 cells and induce the apoptosis of HepG2 cells.This mechanism might be related to the mitochondrial pathway,achieved through the cells arrested in S phase.