红景天苷激活自噬促进肺癌细胞株A549凋亡的作用及机制

Rhoside promotes apoptosis in lung cancer cell line A549 through activation of autophagy

目的观察红景天苷对肺癌细胞株A549自噬及凋亡行为的影响,并探究其作用机制。方法将肺癌细胞A549分为对照组(细胞正常培养),低剂量实验组和高剂量实验组(细胞分别给予40和80μmol·L^(-1)红景天苷处理),3-MA组(细胞给予5 mmol·L^(-1)3-MA进行处理),3-MA+高剂量实验组(细胞给予5 mmol·L^(-1)3-MA和80μmol·L^(-1)红景天苷共同处理)。给药24 h后,以噻唑蓝(MTT)法检测细胞增殖水平,以流式细胞术检测细胞凋亡水平,以免疫荧光染色观察A549中自噬相关蛋白轻链3(LC3)荧光强度变化,以蛋白质印迹(Western Blot)实验分别检测细胞中磷酸化磷酸肌醇3激酶(p-PI3K)、蛋白激酶B(Akt)、雷帕霉素靶蛋白(mTOR)蛋白的表达水平。结果对照组和低、高剂量实验组A549细胞相对存活率分别为100.00%、(61.17±3.16)%和(44.39±2.19)%,细胞凋亡率分别为(3.91±0.67)%、(11.45±0.85)%和(18.09±1.21)%,p-PI3K蛋白相对表达水平分别为1.11±0.08、0.78±0.04和0.40±0.05,p-Akt蛋白相对表达水平分别为0.94±0.03、0.62±0.07和0.32±0.04,p-mTOR蛋白相对表达水平分别为1.16±0.05、0.59±0.06和0.19±0.03,LC3平均荧光强度分别为(51.36±3.02)%、(76.04±3.62)%和(119.88±4.03)%。低、高剂量实验组的上述指标与对照组比较,差异均有统计学意义(均P<0.05)。结论红景天苷可激活肺癌细胞A549自噬,抑制增殖并诱导其凋亡,其机制可能与下调PI3K/Akt/mTOR通路相关。

Objective To observe the effect of salidroside on autophagy and apoptosis in A549 lung cancer cells,and explore its underlying mechanisms.Methods A549 lung cancer cells were divided into control group(cells cultured normally),experimental-L group and experimental-H group(cells treated with 40 and 80μmol·L^(-1)salidroside,respectively),the 3-MA group(cells treated with 5 mmol·L^(-1)3-MA)and the 3-MA+experimental-H group(cells treated with 5 mmol·L^(-1)3-MA and 80μmol·L^(-1) salidroside)were also included.After 24 hours of treatment,cell proliferation was detected by methyl thiazolyl tetrazolium(MTT)assay,cell apoptosis level was measured by flow cytometry,fluorescence intensity of autophagy-related protein light chain 3(LC3)in A549 cells was observed by immunofluorescence staining,and the expression levels of phosphorylated pho sp hatidylinositol-3-kinases(p-PI3K),protein kinase B(Akt),and mammalian target of rapamycin(mTOR)were examined by Western Blot.Results The relative cell viability of the control group,experimental-L group,and experimental-H group were 100.00%,(61.17±3.16)%and(44.39±2.19)%,respectively;the cell apoptosis rates were(3.91±0.67)%,(11.45±0.85)%and(18.09±1.21)%,respectively;the relative expression levels of p-PI3K were 1.11±0.08,0.78±0.04 and 0.40±0.05,respectively;the relative expression levels of p-Akt were 0.94±0.03,0.62±0.07 and 0.32±0.04,respectively;the relative expression levels of p-mTOR were 1.16±0.05,0.59±0.06,and 0.19±0.03,respectively;the average fluorescence intensities of LC3 were(51.36±3.02)%,(76.04±3.62)%and(119.88±4.03)%,respectively.The above-mentioned indicators in the experimental-L and-H groups were significantly different from those in the control group(all P<0.05).Conclusion Salidroside can activate autophagy in A549 lung cancer cells,inhibit proliferation,and induce apoptosis,possibly by downregulating the PI3K/Akt/mTOR pathway.