黄芪多糖通过阻断PTEN-PI3K-Akt信号通路诱导人类KG-1a细胞凋亡的研究

Astragalus polysaccharide induces apoptosis of human KG-1a cells through inhibiting PTEN-PI3K-Akt signaling pathway

目的 研究黄芪多糖（AP）对人类急性髓系白血病KG-1a细胞增殖及凋亡的影响及其作用机制.方法 常规培养急性髓系白血病细胞系KG-1a,进行细胞传代及细胞冻存;CCK-8法检测不同浓度AP对KG-1a细胞增殖的影响;流式细胞术检测AP处理后KG-1a细胞的凋亡率;Westem blot检测运用AP处理48 h后p-Akt及bcl-2蛋白表达变化情况;实时定量PCR检测AP处理后PTEN mRNA表达情况.结果 细胞增殖抑制试验显示AP呈浓度依赖性抑制KG-1a细胞生长;0、100、150μg/ml药物处理细胞48 h后其早期凋亡率分别为（1.98±0.16）％、（12.60±0.48）％、（16.31 ±0.73）％,晚期凋亡率分别为（3.11±0.19）％、（17.17± 1.40）％、（21.17±0.81）％,差异均有统计学意义（均P＜0.05）;与空白对照组相比,AP作用的KG-1a细胞p-Akt及bcl-2蛋白表达水平均降低（均P＜ 0.05）,PTEN mRNA表达水平上升（P＜0.05）.结论 AP能够浓度依赖地抑制KG-1a细胞增殖,其机制可能是通过抑制PTEN-PI3K-Akt信号转导通路来实现的.

Objective To investigate the effect of astragalus polysaccharide （AP） on proliferation and apoptosis of human acute myelocytic leukemia cell line KG-1a and the underlying mechanisms.Methods Human acute myelocytic leukemia cell line KG-la was cultured under 37 ℃ and 5 ％ C02,when appropriate cell passage and cryopreservation were performed.After treatment for 48 h with different concentrations of AP,the proliferative activity and apoptosis rate of KG-1a cells were examined by CCK-8 assay and flow cytometry,respectively.The expressions of p-Akt and bcl-2 protein in AP-treated KG-1a cells were evaluated by Western blot.The expression of PTEN mRNA by quantified real-time PCR.Results The proliferative activity of KG-la cell was obviously suppressed by AP treatment,and the inhibition rate increased in a dosedependent manner.The flow cytometry showed that,compared with the control group,the apoptosis rates of KG-1a cells were significantly increased after treatment with AP for 48 h.The early apoptosis rates were （1.98±0.16） ％,（12.60±0.48） ％,（16.31±0.73） ％,the late apoptotic rates were （3.11±0.19） ％,（17.17±1.40） ％,（21.17 ± 0.81）％,the differences were statistically significant （P ＜ 0.05）.Western blot showed that the expressions of p-Akt and bcl-2 protein in KG-1a cells decreased significantly after treatment with AP （P ＜ 0.05）.In contrast,the mRNA level of PTEN increased （P ＜0.05）,which was shown by real-time PCR.Conclusion AP could repress cellular proliferation activity of KG-1a cells,which could be attributed to inhibition of PTEN-PI3K-Akt signaling pathway.