目的 初步探讨β-榄香烯能否通过抑制PI3K/AKT/mTOR信号通路来诱导A549细胞发生自噬.方法 采用MTT法检测β-榄香烯对A549细胞的增殖抑制率,荧光显微镜下观察吖啶橙染色后的细胞自噬现象,应用Western blot检测β-榄香烯处理后的LC3-Ⅱ、PI3K、AKT、mTOR蛋白变化.结果 β-榄香烯可明显抑制A549细胞增殖,且抑制效果随浓度的增加而增强,β-榄香烯对A549细胞的IC50值为72.45 μg·mL-1.吖啶橙染色结果显示,低浓度(10 μg·mL-1,50 μg·mL-1) β-榄香烯处理A549细胞后形态无异常,用100μg·mL-1、200μg·mL-1、500μg·mL-1浓度的β-榄香烯处理A549细胞时,细胞质逐渐出现空泡化,酸性囊泡增多,而细胞核逐渐浓缩.随着β-榄香烯浓度的增加,自噬相关蛋白LC3-Ⅱ蛋白表达逐渐增高,而PI3K、AKT和mTOR蛋白表达逐渐降低,具有剂量依赖性.结论 β-榄香烯能够通过抑制PI3K/AKT/mTOR通路促进A549细胞自噬,且具有剂量依赖性.%Objective To investigate whether β-elemene could induce cell autophagy by inhibiting PI3K / AKT / mTOR signaling path-way to play an anti-tumor role. Methods MTT method was used to detect proliferation rate of A549 cells after treated with β-elemene. Au-tophagy phenomenon of acridine orange staining was observed under fluorescence microscope. The protein level of LC3- II, PI3K, AKT and mTOR were examined by Western blot after A549 cells treated with β-elemene. Results β-elemene could inhibit the proliferation of A549 cells obviously, and the inhibitory effect was enhanced with the increase of concentration of β-elemene. The IC50value of β-elemene on A549 cells was 72.45 μg·mL-1. Acridine orange staining results showed no abnormality was observed after A549 cells treated with β-elemene of a low concentration (10 μg·mL-1or 50 μg·mL-1). While treated at a high concentration of 100 μg·mL-1, 200 μg·mL-1, 500 μg·mL-1, the A549 cells showed obvious changes such as gradually vacuolated cytoplasm, increased acidic vesicles and gradually condensed nucleus. With the increase of β-elemene concentration, the expression of autophagy-related protein LC3-Ⅱ was gradually increased, while the expressions of PI3K, AKT and mTOR were decreased gradually, in a dose-dependent manner. Conclusion β-elemene could induce au-tophagy of A549 cells in a dose-dependent manner by inhibiting PI3K / AKT / mTOR pathway.
展开▼
